Re: [PATCH v1 3/5] media: stm32-dcmipp: STM32 DCMIPP camera interface driver

From: Sakari Ailus
Date: Mon Aug 07 2023 - 05:30:13 EST


Hi Hugues,

Sorry for the late review. Please ping if you don't get replies! I noticed
this as you replied Dan...

There are multiple drivers here and I haven't commented on similar
constructs on all of them but the comments do still apply.

There have been some API changes, in particular sub-device state. See e.g.
<URL:https://git.linuxtv.org/sailus/media_tree.git/commit/?id=3f516e053ae8e25bc673b8549a8a2bc4bbbd2e9d>.

On Sat, Sep 10, 2022 at 04:40:08PM +0200, Hugues Fruchet wrote:
> This V4L2 subdev driver enables Digital Camera Memory Interface
> Pixel Processor(DCMIPP) of STMicroelectronics STM32 SoC series.
>
> Signed-off-by: Hugues Fruchet <hugues.fruchet@xxxxxxxxxxx>
> ---
> drivers/media/platform/st/stm32/Kconfig | 15 +
> drivers/media/platform/st/stm32/Makefile | 1 +
> .../platform/st/stm32/stm32-dcmipp/Makefile | 5 +
> .../st/stm32/stm32-dcmipp/dcmipp-bytecap.c | 1112 +++++++++++++++++
> .../st/stm32/stm32-dcmipp/dcmipp-byteproc.c | 790 ++++++++++++
> .../st/stm32/stm32-dcmipp/dcmipp-common.c | 116 ++
> .../st/stm32/stm32-dcmipp/dcmipp-common.h | 240 ++++
> .../st/stm32/stm32-dcmipp/dcmipp-core.c | 682 ++++++++++
> .../st/stm32/stm32-dcmipp/dcmipp-parallel.c | 497 ++++++++
> 9 files changed, 3458 insertions(+)
> create mode 100644 drivers/media/platform/st/stm32/stm32-dcmipp/Makefile
> create mode 100644 drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-bytecap.c
> create mode 100644 drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-byteproc.c
> create mode 100644 drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-common.c
> create mode 100644 drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-common.h
> create mode 100644 drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-core.c
> create mode 100644 drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-parallel.c
>
> diff --git a/drivers/media/platform/st/stm32/Kconfig b/drivers/media/platform/st/stm32/Kconfig
> index b22dd4753496..fab531866941 100644
> --- a/drivers/media/platform/st/stm32/Kconfig
> +++ b/drivers/media/platform/st/stm32/Kconfig
> @@ -16,6 +16,21 @@ config VIDEO_STM32_DCMI
> To compile this driver as a module, choose M here: the module
> will be called stm32-dcmi.
>
> +config VIDEO_STM32_DCMIPP
> + tristate "STM32 Digital Camera Memory Interface Pixel Processor (DCMIPP) support"
> + depends on V4L_PLATFORM_DRIVERS
> + depends on VIDEO_DEV && OF
> + depends on MEDIA_CONTROLLER
> + depends on ARCH_STM32 || COMPILE_TEST
> + select VIDEOBUF2_DMA_CONTIG
> + select V4L2_FWNODE
> + help
> + This module makes the STM32 Digital Camera Memory Interface
> + Pixel Processor (DCMIPP) available as a v4l2 device.
> +
> + To compile this driver as a module, choose M here: the module
> + will be called stm32-dcmipp.
> +
> # Mem2mem drivers
> config VIDEO_STM32_DMA2D
> tristate "STM32 Chrom-Art Accelerator (DMA2D)"
> diff --git a/drivers/media/platform/st/stm32/Makefile b/drivers/media/platform/st/stm32/Makefile
> index 896ef98a73ab..7ed8297b9b19 100644
> --- a/drivers/media/platform/st/stm32/Makefile
> +++ b/drivers/media/platform/st/stm32/Makefile
> @@ -1,4 +1,5 @@
> # SPDX-License-Identifier: GPL-2.0-only
> obj-$(CONFIG_VIDEO_STM32_DCMI) += stm32-dcmi.o
> +obj-$(CONFIG_VIDEO_STM32_DCMIPP) += stm32-dcmipp/
> stm32-dma2d-objs := dma2d/dma2d.o dma2d/dma2d-hw.o
> obj-$(CONFIG_VIDEO_STM32_DMA2D) += stm32-dma2d.o
> diff --git a/drivers/media/platform/st/stm32/stm32-dcmipp/Makefile b/drivers/media/platform/st/stm32/stm32-dcmipp/Makefile
> new file mode 100644
> index 000000000000..cbddc98141a4
> --- /dev/null
> +++ b/drivers/media/platform/st/stm32/stm32-dcmipp/Makefile
> @@ -0,0 +1,5 @@
> +# SPDX-License-Identifier: GPL-2.0
> +stm32-dcmipp-y := dcmipp-core.o dcmipp-common.o
> +
> +obj-$(CONFIG_VIDEO_STM32_DCMIPP) += stm32-dcmipp.o
> +obj-$(CONFIG_VIDEO_STM32_DCMIPP) += dcmipp-parallel.o dcmipp-byteproc.o dcmipp-bytecap.o
> diff --git a/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-bytecap.c b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-bytecap.c
> new file mode 100644
> index 000000000000..ae7841913000
> --- /dev/null
> +++ b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-bytecap.c
> @@ -0,0 +1,1112 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for STM32 Digital Camera Memory Interface Pixel Processor
> + *
> + * Copyright (C) STMicroelectronics SA 2022
> + * Authors: Hugues Fruchet <hugues.fruchet@xxxxxxxxxxx>
> + * Alain Volmat <alain.volmat@xxxxxxxxxxx>
> + * for STMicroelectronics.
> + */
> +
> +#include <linux/component.h>
> +#include <linux/delay.h>
> +#include <linux/iopoll.h>
> +#include <linux/module.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/reset.h>
> +#include <media/v4l2-ioctl.h>
> +#include <media/v4l2-mc.h>
> +#include <media/videobuf2-core.h>
> +#include <media/videobuf2-dma-contig.h>
> +
> +#include "dcmipp-common.h"
> +
> +#define DCMIPP_BYTECAP_DRV_NAME "dcmipp-bytecap"
> +
> +#define DCMIPP_PRSR (0x1F8)
> +#define DCMIPP_CMIER (0x3F0)
> +#define DCMIPP_CMIER_P0FRAMEIE BIT(9)
> +#define DCMIPP_CMIER_P0VSYNCIE BIT(10)
> +#define DCMIPP_CMIER_P0OVRIE BIT(15)
> +#define DCMIPP_CMIER_P0ALL (DCMIPP_CMIER_P0VSYNCIE |\
> + DCMIPP_CMIER_P0FRAMEIE |\
> + DCMIPP_CMIER_P0OVRIE)
> +#define DCMIPP_CMSR1 (0x3F4)
> +#define DCMIPP_CMSR2 (0x3F8)
> +#define DCMIPP_CMSR2_P0FRAMEF BIT(9)
> +#define DCMIPP_CMSR2_P0VSYNCF BIT(10)
> +#define DCMIPP_CMSR2_P0OVRF BIT(15)
> +#define DCMIPP_CMFCR (0x3FC)
> +#define DCMIPP_P0FSCR (0x404)
> +#define DCMIPP_P0FSCR_PIPEN BIT(31)
> +#define DCMIPP_P0FCTCR (0x500)
> +#define DCMIPP_P0FCTCR_CPTREQ BIT(3)
> +#define DCMIPP_P0DCCNTR (0x5B0)
> +#define DCMIPP_P0DCLMTR (0x5B4)
> +#define DCMIPP_P0DCLMTR_ENABLE BIT(31)
> +#define DCMIPP_P0DCLMTR_LIMIT_MASK GENMASK(23, 0)
> +#define DCMIPP_P0PPM0AR1 (0x5C4)
> +#define DCMIPP_P0SR (0x5F8)
> +#define DCMIPP_P0SR_CPTACT BIT(23)
> +
> +struct dcmipp_bytecap_pix_map {
> + unsigned int code;
> + u32 pixelformat;
> +};
> +
> +#define PIXMAP_MBUS_PFMT(mbus, fmt) \
> + { \
> + .code = MEDIA_BUS_FMT_##mbus, \
> + .pixelformat = V4L2_PIX_FMT_##fmt \
> + }
> +
> +static const struct dcmipp_bytecap_pix_map dcmipp_bytecap_pix_map_list[] = {
> + PIXMAP_MBUS_PFMT(RGB565_2X8_LE, RGB565),
> + PIXMAP_MBUS_PFMT(YUYV8_2X8, YUYV),
> + PIXMAP_MBUS_PFMT(YVYU8_2X8, YVYU),
> + PIXMAP_MBUS_PFMT(UYVY8_2X8, UYVY),
> + PIXMAP_MBUS_PFMT(VYUY8_2X8, VYUY),
> + PIXMAP_MBUS_PFMT(Y8_1X8, GREY),
> + PIXMAP_MBUS_PFMT(SBGGR8_1X8, SBGGR8),
> + PIXMAP_MBUS_PFMT(SGBRG8_1X8, SGBRG8),
> + PIXMAP_MBUS_PFMT(SGRBG8_1X8, SGRBG8),
> + PIXMAP_MBUS_PFMT(SRGGB8_1X8, SRGGB8),
> + PIXMAP_MBUS_PFMT(JPEG_1X8, JPEG),
> +};
> +
> +static const struct dcmipp_bytecap_pix_map *dcmipp_bytecap_pix_map_by_pixelformat
> + (u32 pixelformat)
> +{
> + const struct dcmipp_bytecap_pix_map *l = dcmipp_bytecap_pix_map_list;
> + unsigned int size = ARRAY_SIZE(dcmipp_bytecap_pix_map_list);
> + unsigned int i;
> +
> + for (i = 0; i < size; i++) {
> + if (l[i].pixelformat == pixelformat)
> + return &l[i];
> + }
> +
> + return NULL;
> +}
> +
> +static const struct dcmipp_bytecap_pix_map *dcmipp_bytecap_pix_map_by_index(unsigned int i)
> +{
> + const struct dcmipp_bytecap_pix_map *l = dcmipp_bytecap_pix_map_list;
> + unsigned int size = ARRAY_SIZE(dcmipp_bytecap_pix_map_list);
> +
> + if (i >= size)
> + return NULL;
> +
> + return &l[i];
> +}
> +
> +struct dcmipp_buf {
> + struct vb2_v4l2_buffer vb;
> + bool prepared;
> + dma_addr_t paddr;
> + size_t size;
> + struct list_head list;
> +};
> +
> +enum state {
> + STOPPED = 0,
> + WAIT_FOR_BUFFER,
> + RUNNING,
> +};
> +
> +struct dcmipp_bytecap_device {
> + struct dcmipp_ent_device ved;
> + struct video_device vdev;
> + struct device *dev;
> + struct device *cdev;
> + struct v4l2_pix_format format;
> + struct vb2_queue queue;
> + struct list_head buffers;
> + /* Protects the access of variables shared within the interrupt */
> + spinlock_t irqlock;
> + /* Protect this data structure */
> + struct mutex lock;
> + u32 sequence;
> + struct media_pipeline pipe;
> +
> + enum state state;
> +
> + /*
> + * DCMIPP driver is handling 2 buffers
> + * active: buffer into which DCMIPP is currently writing into
> + * next: buffer given to the DCMIPP and which will become
> + * automatically active on next VSYNC
> + */
> + struct dcmipp_buf *active, *next;
> +
> + void __iomem *regs;
> + struct reset_control *rstc;
> +
> + u32 cmier;
> + u32 cmsr2;
> +
> + int errors_count;
> + int limit_count;
> + int overrun_count;
> + int buffers_count;
> + int vsync_count;
> + int frame_count;
> + int it_count;
> + int underrun_count;
> + int nactive_count;

These would probably be better unsigned.

> +};
> +
> +static const struct v4l2_pix_format fmt_default = {
> + .width = DCMIPP_FMT_WIDTH_DEFAULT,
> + .height = DCMIPP_FMT_HEIGHT_DEFAULT,
> + .pixelformat = V4L2_PIX_FMT_RGB565,
> + .field = V4L2_FIELD_NONE,
> + .colorspace = DCMIPP_COLORSPACE_DEFAULT,
> + .ycbcr_enc = DCMIPP_YCBCR_ENC_DEFAULT,
> + .quantization = DCMIPP_QUANTIZATION_DEFAULT,
> + .xfer_func = DCMIPP_XFER_FUNC_DEFAULT,
> +};
> +
> +static inline int frame_size(u32 width, u32 height, u32 format)
> +{
> + switch (format) {
> + case V4L2_PIX_FMT_SBGGR8:
> + case V4L2_PIX_FMT_SGBRG8:
> + case V4L2_PIX_FMT_SGRBG8:
> + case V4L2_PIX_FMT_SRGGB8:
> + case V4L2_PIX_FMT_GREY:
> + return (width * height);
> + case V4L2_PIX_FMT_RGB565:
> + case V4L2_PIX_FMT_YUYV:
> + case V4L2_PIX_FMT_YVYU:
> + case V4L2_PIX_FMT_UYVY:
> + case V4L2_PIX_FMT_VYUY:
> + return (width * height * 2);
> + case V4L2_PIX_FMT_JPEG:
> + return (width * height);

No need for the parentheses.

> + default:
> + return 0;
> + }
> +}
> +
> +static inline int frame_stride(u32 width, u32 format)
> +{
> + switch (format) {
> + case V4L2_PIX_FMT_SBGGR8:
> + case V4L2_PIX_FMT_SGBRG8:
> + case V4L2_PIX_FMT_SGRBG8:
> + case V4L2_PIX_FMT_SRGGB8:
> + case V4L2_PIX_FMT_GREY:
> + case V4L2_PIX_FMT_JPEG:
> + return width;
> + case V4L2_PIX_FMT_RGB565:
> + case V4L2_PIX_FMT_YUYV:
> + case V4L2_PIX_FMT_YVYU:
> + case V4L2_PIX_FMT_UYVY:
> + case V4L2_PIX_FMT_VYUY:
> + return (width * 2);
> + default:
> + return 0;
> + }
> +}
> +
> +static inline int hdw_pixel_alignment(u32 format)
> +{
> + /* 16 bytes alignment required by hardware */
> + switch (format) {
> + case V4L2_PIX_FMT_SBGGR8:
> + case V4L2_PIX_FMT_SGBRG8:
> + case V4L2_PIX_FMT_SGRBG8:
> + case V4L2_PIX_FMT_SRGGB8:
> + case V4L2_PIX_FMT_GREY:
> + case V4L2_PIX_FMT_JPEG:
> + return 4;/* 2^4 = 16 pixels = 16 bytes */
> + case V4L2_PIX_FMT_RGB565:
> + case V4L2_PIX_FMT_YUYV:
> + case V4L2_PIX_FMT_YVYU:
> + case V4L2_PIX_FMT_UYVY:
> + case V4L2_PIX_FMT_VYUY:
> + return 3;/* 2^3 = 8 pixels = 16 bytes */

A space after the semicolon? Same above.

> + default:
> + return 0;
> + }
> +}
> +
> +static int dcmipp_bytecap_querycap(struct file *file, void *priv,
> + struct v4l2_capability *cap)
> +{
> + strscpy(cap->driver, DCMIPP_PDEV_NAME, sizeof(cap->driver));
> + strscpy(cap->card, KBUILD_MODNAME, sizeof(cap->card));
> + snprintf(cap->bus_info, sizeof(cap->bus_info),
> + "platform:%s", DCMIPP_PDEV_NAME);

This isn't necessary anymore --- it's handled by v4l_querycap() directly.

> +
> + return 0;
> +}
> +
> +static void dcmipp_bytecap_get_format(struct dcmipp_ent_device *ved,
> + struct v4l2_pix_format *fmt)
> +{
> + struct dcmipp_bytecap_device *vcap = container_of(ved, struct dcmipp_bytecap_device,
> + ved);
> +
> + *fmt = vcap->format;
> +}
> +
> +static int dcmipp_bytecap_g_fmt_vid_cap(struct file *file, void *priv,
> + struct v4l2_format *f)
> +{
> + struct dcmipp_bytecap_device *vcap = video_drvdata(file);
> +
> + f->fmt.pix = vcap->format;
> +
> + return 0;
> +}
> +
> +static int dcmipp_bytecap_try_fmt_vid_cap(struct file *file, void *priv,
> + struct v4l2_format *f)
> +{
> + struct dcmipp_bytecap_device *vcap = video_drvdata(file);
> + struct v4l2_pix_format *format = &f->fmt.pix;
> + const struct dcmipp_bytecap_pix_map *vpix;
> + u32 in_w, in_h;
> +
> + /* Don't accept a pixelformat that is not on the table */
> + vpix = dcmipp_bytecap_pix_map_by_pixelformat(format->pixelformat);
> + if (!vpix)
> + format->pixelformat = fmt_default.pixelformat;
> +
> + /* Adjust width & height */
> + in_w = format->width;
> + in_h = format->height;
> + v4l_bound_align_image(&format->width,
> + DCMIPP_FRAME_MIN_WIDTH, DCMIPP_FRAME_MAX_WIDTH,
> + hdw_pixel_alignment(format->pixelformat),
> + &format->height,
> + DCMIPP_FRAME_MIN_HEIGHT, DCMIPP_FRAME_MAX_HEIGHT,
> + hdw_pixel_alignment(format->pixelformat),
> + 0);
> + if (format->width != in_w || format->height != in_h)
> + dev_dbg(vcap->dev,
> + "resolution updated: %dx%d -> %dx%d\n",
> + in_w, in_h, format->width, format->height);
> +
> + format->bytesperline = frame_stride(format->width, format->pixelformat);
> + format->sizeimage = frame_size(format->width, format->height, format->pixelformat);

Please run:

./scripts/checkpatch.pl --strict --max-line-length=80

> +
> + if (format->field == V4L2_FIELD_ANY)
> + format->field = fmt_default.field;
> +
> + dcmipp_colorimetry_clamp(format);
> +
> + return 0;
> +}
> +
> +static int dcmipp_bytecap_s_fmt_vid_cap(struct file *file, void *priv,
> + struct v4l2_format *f)
> +{
> + struct dcmipp_bytecap_device *vcap = video_drvdata(file);
> + int ret;
> +
> + /* Do not change the format while stream is on */
> + if (vb2_is_busy(&vcap->queue))
> + return -EBUSY;
> +
> + ret = dcmipp_bytecap_try_fmt_vid_cap(file, priv, f);
> + if (ret)
> + return ret;
> +
> + dev_dbg(vcap->dev, "%s: format update: old:%dx%d (0x%x, %d, %d, %d, %d) new:%dx%d (0x%x, %d, %d, %d, %d)\n",
> + vcap->vdev.name,
> + /* old */
> + vcap->format.width, vcap->format.height,
> + vcap->format.pixelformat, vcap->format.colorspace,
> + vcap->format.quantization, vcap->format.xfer_func,
> + vcap->format.ycbcr_enc,
> + /* new */
> + f->fmt.pix.width, f->fmt.pix.height,
> + f->fmt.pix.pixelformat, f->fmt.pix.colorspace,
> + f->fmt.pix.quantization, f->fmt.pix.xfer_func,
> + f->fmt.pix.ycbcr_enc);
> +
> + vcap->format = f->fmt.pix;
> +
> + return 0;
> +}
> +
> +static int dcmipp_bytecap_enum_fmt_vid_cap(struct file *file, void *priv,
> + struct v4l2_fmtdesc *f)
> +{
> + const struct dcmipp_bytecap_pix_map *vpix = dcmipp_bytecap_pix_map_by_index(f->index);

This function is used only once, please move the code here.

> +
> + if (!vpix)
> + return -EINVAL;
> +
> + f->pixelformat = vpix->pixelformat;
> +
> + return 0;
> +}
> +
> +static int dcmipp_bytecap_enum_framesizes(struct file *file, void *fh,
> + struct v4l2_frmsizeenum *fsize)
> +{
> + const struct dcmipp_bytecap_pix_map *vpix;
> +
> + if (fsize->index)
> + return -EINVAL;
> +
> + /* Only accept code in the pix map table */
> + vpix = dcmipp_bytecap_pix_map_by_pixelformat(fsize->pixel_format);
> + if (!vpix)
> + return -EINVAL;
> +
> + fsize->type = V4L2_FRMSIZE_TYPE_CONTINUOUS;
> + fsize->stepwise.min_width = DCMIPP_FRAME_MIN_WIDTH;
> + fsize->stepwise.max_width = DCMIPP_FRAME_MAX_WIDTH;
> + fsize->stepwise.min_height = DCMIPP_FRAME_MIN_HEIGHT;
> + fsize->stepwise.max_height = DCMIPP_FRAME_MAX_HEIGHT;
> + fsize->stepwise.step_width = 1;
> + fsize->stepwise.step_height = 1;
> +
> + return 0;
> +}
> +
> +/* TODO - based on the explanation text, should also use v4l2_pipeline_link_notify */
> +static int dcmipp_bytecap_open(struct file *file)
> +{
> + struct dcmipp_bytecap_device *vcap = video_drvdata(file);
> + int ret;
> +
> + ret = mutex_lock_interruptible(&vcap->lock);
> + if (ret)
> + return ret;
> +
> + ret = v4l2_fh_open(file);
> + if (ret)
> + goto err_unlock;
> +
> + ret = v4l2_pipeline_pm_get(&vcap->vdev.entity);

You shouldn't do this anymore, instead please change any sensor driver you
need to use runtime PM.

> + if (ret)
> + goto err_close;
> +
> + mutex_unlock(&vcap->lock);
> +
> + return 0;
> +
> +err_close:
> + v4l2_fh_release(file);
> +err_unlock:
> + mutex_unlock(&vcap->lock);
> +
> + return ret;
> +}
> +
> +static int dcmipp_bytecap_close(struct file *file)
> +{
> + struct dcmipp_bytecap_device *vcap = video_drvdata(file);
> +
> + vb2_fop_release(file);
> +
> + v4l2_pipeline_pm_put(&vcap->vdev.entity);
> +
> + return 0;
> +}
> +
> +static const struct v4l2_file_operations dcmipp_bytecap_fops = {
> + .owner = THIS_MODULE,
> + .open = dcmipp_bytecap_open,
> + .release = dcmipp_bytecap_close,
> + .read = vb2_fop_read,
> + .poll = vb2_fop_poll,
> + .unlocked_ioctl = video_ioctl2,
> + .mmap = vb2_fop_mmap,
> +};
> +
> +static const struct v4l2_ioctl_ops dcmipp_bytecap_ioctl_ops = {
> + .vidioc_querycap = dcmipp_bytecap_querycap,
> +
> + .vidioc_g_fmt_vid_cap = dcmipp_bytecap_g_fmt_vid_cap,
> + .vidioc_s_fmt_vid_cap = dcmipp_bytecap_s_fmt_vid_cap,
> + .vidioc_try_fmt_vid_cap = dcmipp_bytecap_try_fmt_vid_cap,
> + .vidioc_enum_fmt_vid_cap = dcmipp_bytecap_enum_fmt_vid_cap,
> + .vidioc_enum_framesizes = dcmipp_bytecap_enum_framesizes,
> +
> + .vidioc_reqbufs = vb2_ioctl_reqbufs,
> + .vidioc_create_bufs = vb2_ioctl_create_bufs,
> + .vidioc_prepare_buf = vb2_ioctl_prepare_buf,
> + .vidioc_querybuf = vb2_ioctl_querybuf,
> + .vidioc_qbuf = vb2_ioctl_qbuf,
> + .vidioc_dqbuf = vb2_ioctl_dqbuf,
> + .vidioc_expbuf = vb2_ioctl_expbuf,
> + .vidioc_streamon = vb2_ioctl_streamon,
> + .vidioc_streamoff = vb2_ioctl_streamoff,
> +};
> +
> +static int dcmipp_pipeline_s_stream(struct dcmipp_bytecap_device *vcap,
> + int state)
> +{
> + struct media_entity *entity = &vcap->vdev.entity;
> + struct v4l2_subdev *subdev;
> + struct media_pad *pad;
> + int ret;
> +
> + /* Start/stop all entities within pipeline */
> + while (1) {
> + pad = &entity->pads[0];
> + if (!(pad->flags & MEDIA_PAD_FL_SINK))
> + break;
> +
> + pad = media_pad_remote_pad_first(pad);
> + if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
> + break;
> +
> + entity = pad->entity;
> + subdev = media_entity_to_v4l2_subdev(entity);
> +
> + ret = v4l2_subdev_call(subdev, video, s_stream, state);

Does this driver handle multiple sub-devices in the same pipeline?

If not, then you don't need a loop here.

> + if (ret < 0 && ret != -ENOIOCTLCMD) {
> + dev_err(vcap->dev, "%s: \"%s\" failed to %s streaming (%d)\n",
> + __func__, subdev->name,
> + state ? "start" : "stop", ret);
> +
> + if (!state)
> + v4l2_subdev_call(subdev, core, s_power, state);
> +
> + return ret;
> + }
> +
> + dev_dbg(vcap->dev, "\"%s\" is %s\n",
> + subdev->name, state ? "started" : "stopped");
> + }
> +
> + return 0;
> +}
> +
> +static void dcmipp_start_capture(struct dcmipp_bytecap_device *vcap,
> + struct dcmipp_buf *buf)
> +{
> + /* Set buffer address */
> + reg_write(vcap, DCMIPP_P0PPM0AR1, buf->paddr);
> + dev_dbg(vcap->dev, "Write [%d] %p phy=%pad\n", buf->vb.vb2_buf.index, buf, &buf->paddr);
> +
> + /* Set buffer size */
> + reg_write(vcap, DCMIPP_P0DCLMTR, DCMIPP_P0DCLMTR_ENABLE |
> + ((buf->size / 4) & DCMIPP_P0DCLMTR_LIMIT_MASK));
> +
> + /* Capture request */
> + reg_set(vcap, DCMIPP_P0FCTCR, DCMIPP_P0FCTCR_CPTREQ);
> +}
> +
> +static int dcmipp_bytecap_start_streaming(struct vb2_queue *vq,
> + unsigned int count)
> +{
> + struct dcmipp_bytecap_device *vcap = vb2_get_drv_priv(vq);
> + struct media_entity *entity = &vcap->vdev.entity;
> + struct dcmipp_buf *buf, *node;
> + int ret;
> +
> + vcap->sequence = 0;
> + vcap->errors_count = 0;
> + vcap->limit_count = 0;
> + vcap->overrun_count = 0;
> + vcap->buffers_count = 0;
> + vcap->vsync_count = 0;
> + vcap->frame_count = 0;
> + vcap->it_count = 0;
> + vcap->underrun_count = 0;
> + vcap->nactive_count = 0;

What if you put these into a struct? You could also use memset() on it.

> +
> + ret = pm_runtime_get_sync(vcap->cdev);
> + if (ret < 0) {
> + dev_err(vcap->dev, "%s: Failed to start streaming, cannot get sync (%d)\n",
> + __func__, ret);
> + goto err_pm_put;
> + }
> +
> + /* Start the media pipeline */
> + ret = media_pipeline_start(entity, &vcap->pipe);
> + if (ret) {
> + dev_err(vcap->dev, "%s: Failed to start streaming, media pipeline start error (%d)\n",
> + __func__, ret);
> + goto err_pm_put;
> + }
> +
> + /* Start all the elements within pipeline */
> + ret = dcmipp_pipeline_s_stream(vcap, 1);
> + if (ret)
> + goto err_media_pipeline_stop;
> +
> + spin_lock_irq(&vcap->irqlock);
> +
> + /* Enable pipe at the end of programming */
> + reg_set(vcap, DCMIPP_P0FSCR, DCMIPP_P0FSCR_PIPEN);
> +
> + /*
> + * Start capture if at least one buffer has been queued,
> + * otherwise start is deferred at next buffer queueing
> + */
> + buf = list_first_entry_or_null(&vcap->buffers, typeof(*buf), list);
> + if (!buf) {
> + dev_dbg(vcap->dev, "Start streaming is deferred to next buffer queueing\n");
> + vcap->next = NULL;
> + vcap->state = WAIT_FOR_BUFFER;
> + spin_unlock_irq(&vcap->irqlock);
> + return 0;
> + }
> + vcap->next = buf;
> + dev_dbg(vcap->dev, "Start with next [%d] %p phy=%pad\n",
> + buf->vb.vb2_buf.index, buf, &buf->paddr);
> +
> + /* Start capture */
> + dcmipp_start_capture(vcap, buf);
> +
> + /* Enable interruptions */
> + vcap->cmier |= DCMIPP_CMIER_P0ALL;
> + reg_set(vcap, DCMIPP_CMIER, vcap->cmier);
> +
> + vcap->state = RUNNING;
> +
> + spin_unlock_irq(&vcap->irqlock);
> +
> + return 0;
> +
> +err_media_pipeline_stop:
> + media_pipeline_stop(entity);
> +err_pm_put:
> + pm_runtime_put(vcap->cdev);
> + spin_lock_irq(&vcap->irqlock);
> + /*
> + * Return all buffers to vb2 in QUEUED state.
> + * This will give ownership back to userspace
> + */
> + list_for_each_entry_safe(buf, node, &vcap->buffers, list) {
> + list_del_init(&buf->list);
> + vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_QUEUED);
> + }
> + vcap->active = NULL;
> + spin_unlock_irq(&vcap->irqlock);
> +
> + return ret;
> +}
> +
> +static void dcmipp_dump_status(struct dcmipp_bytecap_device *vcap)
> +{
> + struct device *dev = vcap->dev;
> +
> + dev_dbg(dev, "[DCMIPP_PRSR] =%#10.8x\n", reg_read(vcap, DCMIPP_PRSR));
> + dev_dbg(dev, "[DCMIPP_P0SR] =%#10.8x\n", reg_read(vcap, DCMIPP_P0SR));
> + dev_dbg(dev, "[DCMIPP_P0DCCNTR]=%#10.8x\n",
> + reg_read(vcap, DCMIPP_P0DCCNTR));
> + dev_dbg(dev, "[DCMIPP_CMSR1] =%#10.8x\n", reg_read(vcap, DCMIPP_CMSR1));
> + dev_dbg(dev, "[DCMIPP_CMSR2] =%#10.8x\n", reg_read(vcap, DCMIPP_CMSR2));
> +}
> +
> +/*
> + * Stop the stream engine. Any remaining buffers in the stream queue are
> + * dequeued and passed on to the vb2 framework marked as STATE_ERROR.
> + */
> +static void dcmipp_bytecap_stop_streaming(struct vb2_queue *vq)
> +{
> + struct dcmipp_bytecap_device *vcap = vb2_get_drv_priv(vq);
> + struct dcmipp_buf *buf, *node;
> + int ret;
> + u32 status;
> +
> + dcmipp_pipeline_s_stream(vcap, 0);
> +
> + /* Stop the media pipeline */
> + media_pipeline_stop(&vcap->vdev.entity);
> +
> + /* Disable interruptions */
> + reg_clear(vcap, DCMIPP_CMIER, vcap->cmier);
> +
> + /* Stop capture */
> + reg_clear(vcap, DCMIPP_P0FCTCR, DCMIPP_P0FCTCR_CPTREQ);
> +
> + /* Wait until CPTACT become 0 */
> + ret = readl_relaxed_poll_timeout(vcap->regs + DCMIPP_P0SR,
> + status,
> + !(status & DCMIPP_P0SR_CPTACT),
> + 20, 1000);
> + if (ret)
> + dev_warn(vcap->dev, "Timeout when stopping\n");
> +
> + /* Disable pipe */
> + reg_clear(vcap, DCMIPP_P0FSCR, DCMIPP_P0FSCR_PIPEN);
> +
> + spin_lock_irq(&vcap->irqlock);
> +
> + /* Return all queued buffers to vb2 in ERROR state */
> + list_for_each_entry_safe(buf, node, &vcap->buffers, list) {
> + list_del_init(&buf->list);
> + vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
> + }
> + INIT_LIST_HEAD(&vcap->buffers);
> +
> + vcap->active = NULL;
> + vcap->state = STOPPED;
> +
> + dcmipp_dump_status(vcap);
> +
> + spin_unlock_irq(&vcap->irqlock);
> +
> + pm_runtime_put(vcap->cdev);
> +
> + if (ret) {
> + /* Reset IP on timeout */
> + if (reset_control_assert(vcap->rstc))
> + dev_warn(vcap->dev, "Failed to assert the reset line\n");
> +
> + usleep_range(3000, 5000);
> +
> + if (reset_control_deassert(vcap->rstc))
> + dev_warn(vcap->dev, "Failed to deassert the reset line\n");
> + }
> +
> + if (vcap->errors_count)
> + dev_warn(vcap->dev, "Some errors found while streaming: errors=%d (overrun=%d, limit=%d, nactive=%d), underrun=%d, buffers=%d\n",
> + vcap->errors_count, vcap->overrun_count, vcap->limit_count,
> + vcap->nactive_count, vcap->underrun_count, vcap->buffers_count);
> + dev_dbg(vcap->dev, "Stop streaming, errors=%d (overrun=%d, limit=%d, nactive=%d), underrun=%d, vsync=%d, frame=%d, buffers=%d, it=%d\n",
> + vcap->errors_count, vcap->overrun_count, vcap->limit_count,
> + vcap->nactive_count, vcap->underrun_count, vcap->vsync_count,
> + vcap->frame_count, vcap->buffers_count, vcap->it_count);
> +}
> +
> +static int dcmipp_bytecap_buf_prepare(struct vb2_buffer *vb)
> +{
> + struct dcmipp_bytecap_device *vcap = vb2_get_drv_priv(vb->vb2_queue);
> + struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
> + struct dcmipp_buf *buf = container_of(vbuf, struct dcmipp_buf, vb);
> + unsigned long size;
> +
> + size = vcap->format.sizeimage;
> +
> + if (vb2_plane_size(vb, 0) < size) {
> + dev_err(vcap->dev, "%s data will not fit into plane (%lu < %lu)\n",
> + __func__, vb2_plane_size(vb, 0), size);
> + return -EINVAL;
> + }
> +
> + vb2_set_plane_payload(vb, 0, size);
> +
> + if (!buf->prepared) {
> + /* Get memory addresses */
> + buf->paddr =
> + vb2_dma_contig_plane_dma_addr(&buf->vb.vb2_buf, 0);
> + buf->size = vb2_plane_size(&buf->vb.vb2_buf, 0);
> + buf->prepared = true;
> +
> + vb2_set_plane_payload(&buf->vb.vb2_buf, 0, buf->size);
> +
> + dev_dbg(vcap->dev, "Setup [%d] phy=%pad size=%zu\n",
> + vb->index, &buf->paddr, buf->size);
> + }
> +
> + return 0;
> +}
> +
> +static void dcmipp_bytecap_buf_queue(struct vb2_buffer *vb2_buf)
> +{
> + struct dcmipp_bytecap_device *vcap =
> + vb2_get_drv_priv(vb2_buf->vb2_queue);
> + struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb2_buf);
> + struct dcmipp_buf *buf = container_of(vbuf, struct dcmipp_buf, vb);
> +
> + spin_lock_irq(&vcap->irqlock);
> + list_add_tail(&buf->list, &vcap->buffers);
> +
> + dev_dbg(vcap->dev, "Queue [%d] %p phy=%pad\n", buf->vb.vb2_buf.index, buf, &buf->paddr);
> +
> + if (vcap->state == WAIT_FOR_BUFFER) {
> + vcap->next = buf;
> + dev_dbg(vcap->dev, "Restart with next [%d] %p phy=%pad\n",
> + buf->vb.vb2_buf.index, buf, &buf->paddr);
> +
> + dcmipp_start_capture(vcap, buf);
> +
> + vcap->state = RUNNING;
> +
> + spin_unlock_irq(&vcap->irqlock);
> +
> + return;
> + }
> +
> + spin_unlock_irq(&vcap->irqlock);
> +}
> +
> +static int dcmipp_bytecap_queue_setup(struct vb2_queue *vq,
> + unsigned int *nbuffers,
> + unsigned int *nplanes,
> + unsigned int sizes[],
> + struct device *alloc_devs[])
> +{
> + struct dcmipp_bytecap_device *vcap = vb2_get_drv_priv(vq);
> + unsigned int size;
> +
> + size = vcap->format.sizeimage;
> +
> + /* Make sure the image size is large enough */
> + if (*nplanes)
> + return sizes[0] < vcap->format.sizeimage ? -EINVAL : 0;
> +
> + *nplanes = 1;
> + sizes[0] = vcap->format.sizeimage;
> +
> + dev_dbg(vcap->dev, "Setup queue, count=%d, size=%d\n",
> + *nbuffers, size);
> +
> + return 0;
> +}
> +
> +static int dcmipp_bytecap_buf_init(struct vb2_buffer *vb)
> +{
> + struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
> + struct dcmipp_buf *buf = container_of(vbuf, struct dcmipp_buf, vb);
> +
> + INIT_LIST_HEAD(&buf->list);
> +
> + return 0;
> +}
> +
> +static const struct vb2_ops dcmipp_bytecap_qops = {
> + .start_streaming = dcmipp_bytecap_start_streaming,
> + .stop_streaming = dcmipp_bytecap_stop_streaming,
> + .buf_init = dcmipp_bytecap_buf_init,
> + .buf_prepare = dcmipp_bytecap_buf_prepare,
> + .buf_queue = dcmipp_bytecap_buf_queue,
> + .queue_setup = dcmipp_bytecap_queue_setup,
> + /*
> + * Since q->lock is set we can use the standard
> + * vb2_ops_wait_prepare/finish helper functions.
> + */
> + .wait_prepare = vb2_ops_wait_prepare,
> + .wait_finish = vb2_ops_wait_finish,
> +};
> +
> +static const struct media_entity_operations dcmipp_bytecap_mops = {
> + .link_validate = dcmipp_link_validate,
> +};
> +
> +static void dcmipp_bytecap_release(struct video_device *vdev)
> +{
> + struct dcmipp_bytecap_device *vcap =
> + container_of(vdev, struct dcmipp_bytecap_device, vdev);
> +
> + dcmipp_pads_cleanup(vcap->ved.pads);
> + kfree(vcap);
> +}
> +
> +static void dcmipp_bytecap_comp_unbind(struct device *comp,
> + struct device *master,
> + void *master_data)
> +{
> + struct dcmipp_ent_device *ved = dev_get_drvdata(comp);
> + struct dcmipp_bytecap_device *vcap =
> + container_of(ved, struct dcmipp_bytecap_device, ved);
> +
> + media_entity_cleanup(ved->ent);
> + vb2_video_unregister_device(&vcap->vdev);
> +}
> +
> +static void dcmipp_buffer_done(struct dcmipp_bytecap_device *vcap,
> + struct dcmipp_buf *buf,
> + size_t bytesused,
> + int err)
> +{
> + struct vb2_v4l2_buffer *vbuf;
> +
> + list_del_init(&buf->list);
> +
> + vbuf = &buf->vb;
> +
> + vbuf->sequence = vcap->sequence++;
> + vbuf->field = V4L2_FIELD_NONE;
> + vbuf->vb2_buf.timestamp = ktime_get_ns();
> + vb2_set_plane_payload(&vbuf->vb2_buf, 0, bytesused);
> + vb2_buffer_done(&vbuf->vb2_buf,
> + err ? VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
> + dev_dbg(vcap->dev, "Done [%d] %p phy=%pad\n", buf->vb.vb2_buf.index, buf, &buf->paddr);
> + vcap->buffers_count++;
> +}
> +
> +/* irqlock must be held */
> +static void dcmipp_bytecap_set_next_frame_or_stop(struct dcmipp_bytecap_device *vcap)
> +{
> + if (!vcap->next && list_is_singular(&vcap->buffers)) {
> + /*
> + * If there is no available buffer (none or a single one in the list while two
> + * are expected), stop the capture (effective for next frame). On-going frame
> + * capture will continue till FRAME END but no further capture will be done.
> + */
> + reg_clear(vcap, DCMIPP_P0FCTCR, DCMIPP_P0FCTCR_CPTREQ);
> +
> + dev_dbg(vcap->dev, "Capture restart is deferred to next buffer queueing\n");
> + vcap->next = NULL;
> + vcap->state = WAIT_FOR_BUFFER;
> + return;
> + }
> +
> + /* If we don't have buffer yet, pick the one after active */
> + if (!vcap->next)
> + vcap->next = list_next_entry(vcap->active, list);
> +
> + /*
> + * Set buffer address
> + * This register is shadowed and will be taken into
> + * account on next VSYNC (start of next frame)
> + */
> + reg_write(vcap, DCMIPP_P0PPM0AR1, vcap->next->paddr);
> + dev_dbg(vcap->dev, "Write [%d] %p phy=%pad\n",
> + vcap->next->vb.vb2_buf.index, vcap->next, &vcap->next->paddr);
> +}
> +
> +/* irqlock must be held */
> +static void dcmipp_bytecap_process_frame(struct dcmipp_bytecap_device *vcap,
> + size_t bytesused)
> +{
> + int err = 0;
> + struct dcmipp_buf *buf = vcap->active;
> +
> + if (!buf) {
> + vcap->nactive_count++;
> + vcap->errors_count++;
> + return;
> + }
> +
> + if (bytesused > buf->size) {
> + dev_dbg(vcap->dev, "frame larger than expected (%zu > %zu)\n",
> + bytesused, buf->size);
> + /* Clip to buffer size and return buffer to V4L2 in error */
> + bytesused = buf->size;
> + vcap->limit_count++;
> + vcap->errors_count++;
> + err = -EOVERFLOW;
> + }
> +
> + dcmipp_buffer_done(vcap, buf, bytesused, err);
> + vcap->active = NULL;
> +}
> +
> +static irqreturn_t dcmipp_bytecap_irq_thread(int irq, void *arg)
> +{
> + struct dcmipp_bytecap_device *vcap =
> + container_of(arg, struct dcmipp_bytecap_device, ved);
> + size_t bytesused = 0;
> + u32 cmsr2;
> +
> + spin_lock_irq(&vcap->irqlock);
> +
> + cmsr2 = vcap->cmsr2 & vcap->cmier;
> +
> + /*
> + * If we have an overrun, a frame-end will probably not be generated, in that
> + * case the active buffer will be recycled as next buffer by the VSYNC handler
> + */
> + if (cmsr2 & DCMIPP_CMSR2_P0OVRF) {
> + vcap->errors_count++;
> + vcap->overrun_count++;
> + }
> +
> + if (cmsr2 & DCMIPP_CMSR2_P0FRAMEF) {
> + vcap->frame_count++;
> +
> + /* Read captured buffer size */
> + bytesused = reg_read(vcap, DCMIPP_P0DCCNTR);
> + dcmipp_bytecap_process_frame(vcap, bytesused);
> + }
> +
> + if (cmsr2 & DCMIPP_CMSR2_P0VSYNCF) {
> + vcap->vsync_count++;
> + if (vcap->state == WAIT_FOR_BUFFER) {
> + vcap->underrun_count++;
> + goto out;
> + }
> +
> + /*
> + * On VSYNC, the previously set next buffer is going to become active thanks to
> + * the shadowing mechanism of the DCMIPP. In most of the cases, since a FRAMEEND
> + * has already come, pointer next is NULL since active is reset during the
> + * FRAMEEND handling. However, in case of framerate adjustment, there are more
> + * VSYNC than FRAMEEND. Thus we recycle the active (but not used) buffer and put it
> + * back into next.
> + */
> + swap(vcap->active, vcap->next);
> + dcmipp_bytecap_set_next_frame_or_stop(vcap);
> + }
> +
> +out:
> + spin_unlock_irq(&vcap->irqlock);
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t dcmipp_bytecap_irq_callback(int irq, void *arg)
> +{
> + struct dcmipp_bytecap_device *vcap =
> + container_of(arg, struct dcmipp_bytecap_device, ved);
> +
> + /* Store interrupt status register */
> + vcap->cmsr2 = reg_read(vcap, DCMIPP_CMSR2) & vcap->cmier;
> + vcap->it_count++;
> +
> + /* Clear interrupt */
> + reg_write(vcap, DCMIPP_CMFCR, vcap->cmsr2);
> +
> + return IRQ_WAKE_THREAD;
> +}
> +
> +static int dcmipp_bytecap_comp_bind(struct device *comp, struct device *master,
> + void *master_data)
> +{
> + struct dcmipp_bind_data *bind_data = master_data;
> + struct dcmipp_platform_data *pdata = comp->platform_data;
> + struct dcmipp_bytecap_device *vcap;
> + struct v4l2_pix_format *format;
> + struct video_device *vdev;
> + struct vb2_queue *q;
> + int ret = 0;
> +
> + /* Allocate the dcmipp_bytecap_device struct */
> + vcap = kzalloc(sizeof(*vcap), GFP_KERNEL);
> + if (!vcap)
> + return -ENOMEM;
> +
> + /* Allocate the pads */
> + vcap->ved.pads =
> + dcmipp_pads_init(1,
> + (const unsigned long[1]) {MEDIA_PAD_FL_SINK});
> + if (IS_ERR(vcap->ved.pads)) {
> + ret = PTR_ERR(vcap->ved.pads);
> + goto err_free_vcap;
> + }
> +
> + /* Initialize the media entity */
> + vcap->vdev.entity.name = pdata->entity_name;
> + vcap->vdev.entity.function = MEDIA_ENT_F_IO_V4L;
> + ret = media_entity_pads_init(&vcap->vdev.entity,
> + 1, vcap->ved.pads);

Fits on the same line.

> + if (ret)
> + goto err_clean_pads;
> +
> + /* Initialize the lock */
> + mutex_init(&vcap->lock);
> +
> + /* Initialize the vb2 queue */
> + q = &vcap->queue;
> + q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
> + q->io_modes = VB2_MMAP | VB2_READ | VB2_DMABUF;
> + q->lock = &vcap->lock;
> + q->drv_priv = vcap;
> + q->buf_struct_size = sizeof(struct dcmipp_buf);
> + q->ops = &dcmipp_bytecap_qops;
> + q->mem_ops = &vb2_dma_contig_memops;
> + q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
> + q->min_buffers_needed = 1;
> + q->dev = comp;
> +
> + ret = vb2_queue_init(q);
> + if (ret) {
> + dev_err(comp, "%s: vb2 queue init failed (err=%d)\n",
> + pdata->entity_name, ret);
> + goto err_clean_m_ent;
> + }
> +
> + /* Initialize buffer list and its lock */
> + INIT_LIST_HEAD(&vcap->buffers);
> + spin_lock_init(&vcap->irqlock);
> +
> + /* Set default frame format */
> + vcap->format = fmt_default;
> + format = &vcap->format;
> + format->bytesperline = frame_stride(format->width, format->pixelformat);
> + format->sizeimage = frame_size(format->width,
> + format->height,

Fits on the same line.

> + format->pixelformat);
> +
> + /* Fill the dcmipp_ent_device struct */
> + vcap->ved.ent = &vcap->vdev.entity;
> + vcap->ved.vdev_get_format = dcmipp_bytecap_get_format;
> + vcap->ved.handler = dcmipp_bytecap_irq_callback;
> + vcap->ved.thread_fn = dcmipp_bytecap_irq_thread;
> + dev_set_drvdata(comp, &vcap->ved);
> + vcap->dev = comp;
> + vcap->regs = bind_data->regs;
> + vcap->rstc = bind_data->rstc;
> + vcap->cdev = master;
> +
> + /* Initialize the video_device struct */
> + vdev = &vcap->vdev;
> + vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING |
> + V4L2_CAP_READWRITE;
> + vdev->entity.ops = &dcmipp_bytecap_mops;
> + vdev->release = dcmipp_bytecap_release;
> + vdev->fops = &dcmipp_bytecap_fops;
> + vdev->ioctl_ops = &dcmipp_bytecap_ioctl_ops;
> + vdev->lock = &vcap->lock;
> + vdev->queue = q;
> + vdev->v4l2_dev = bind_data->v4l2_dev;
> + strscpy(vdev->name, pdata->entity_name, sizeof(vdev->name));
> + video_set_drvdata(vdev, &vcap->ved);
> +
> + /* Register the video_device with the v4l2 and the media framework */
> + ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
> + if (ret) {
> + dev_err(comp, "%s: video register failed (err=%d)\n",
> + vcap->vdev.name, ret);
> + goto err_clean_m_ent;
> + }
> +
> + return 0;
> +
> +err_clean_m_ent:
> + media_entity_cleanup(&vcap->vdev.entity);
> +err_clean_pads:
> + dcmipp_pads_cleanup(vcap->ved.pads);
> +err_free_vcap:
> + kfree(vcap);
> +
> + return ret;
> +}
> +
> +static const struct component_ops dcmipp_bytecap_comp_ops = {
> + .bind = dcmipp_bytecap_comp_bind,
> + .unbind = dcmipp_bytecap_comp_unbind,
> +};
> +
> +static int dcmipp_bytecap_probe(struct platform_device *pdev)
> +{
> + return component_add(&pdev->dev, &dcmipp_bytecap_comp_ops);
> +}
> +
> +static int dcmipp_bytecap_remove(struct platform_device *pdev)
> +{
> + component_del(&pdev->dev, &dcmipp_bytecap_comp_ops);
> +
> + return 0;
> +}
> +
> +static const struct platform_device_id dcmipp_bytecap_driver_ids[] = {
> + {
> + .name = DCMIPP_BYTECAP_DRV_NAME,
> + },
> + { }
> +};
> +
> +static struct platform_driver dcmipp_bytecap_pdrv = {
> + .probe = dcmipp_bytecap_probe,
> + .remove = dcmipp_bytecap_remove,
> + .id_table = dcmipp_bytecap_driver_ids,
> + .driver = {
> + .name = DCMIPP_BYTECAP_DRV_NAME,
> + },
> +};
> +
> +module_platform_driver(dcmipp_bytecap_pdrv);
> +
> +MODULE_DEVICE_TABLE(platform, dcmipp_bytecap_driver_ids);
> +
> +MODULE_AUTHOR("Hugues Fruchet <hugues.fruchet@xxxxxxxxxxx>");
> +MODULE_AUTHOR("Alain Volmat <alain.volmat@xxxxxxxxxxx>");
> +MODULE_DESCRIPTION("STMicroelectronics STM32 Digital Camera Memory Interface with Pixel Processor driver");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-byteproc.c b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-byteproc.c
> new file mode 100644
> index 000000000000..5458162a36bf
> --- /dev/null
> +++ b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-byteproc.c
> @@ -0,0 +1,790 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for STM32 Digital Camera Memory Interface Pixel Processor
> + *
> + * Copyright (C) STMicroelectronics SA 2022
> + * Authors: Hugues Fruchet <hugues.fruchet@xxxxxxxxxxx>
> + * Alain Volmat <alain.volmat@xxxxxxxxxxx>
> + * for STMicroelectronics.
> + */
> +
> +#include <linux/component.h>
> +#include <linux/delay.h>
> +#include <linux/module.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/platform_device.h>
> +#include <linux/vmalloc.h>
> +#include <linux/v4l2-mediabus.h>
> +#include <media/v4l2-rect.h>
> +#include <media/v4l2-subdev.h>
> +
> +#include "dcmipp-common.h"
> +
> +#define DCMIPP_BYTEPROC_DRV_NAME "dcmipp-byteproc"
> +
> +#define DCMIPP_FMT_WIDTH_DEFAULT 640
> +#define DCMIPP_FMT_HEIGHT_DEFAULT 480
> +
> +#define DCMIPP_P0FCTCR (0x500)
> +#define DCMIPP_P0FCTCR_FRATE_MASK GENMASK(1, 0)
> +#define DCMIPP_P0SCSTR (0x504)
> +#define DCMIPP_P0SCSTR_HSTART_SHIFT 0
> +#define DCMIPP_P0SCSTR_VSTART_SHIFT 16
> +#define DCMIPP_P0SCSZR (0x508)
> +#define DCMIPP_P0SCSZR_ENABLE BIT(31)
> +#define DCMIPP_P0SCSZR_HSIZE_SHIFT 0
> +#define DCMIPP_P0SCSZR_VSIZE_SHIFT 16
> +#define DCMIPP_P0PPCR (0x5C0)
> +#define DCMIPP_P0PPCR_BSM_1_2 0x1
> +#define DCMIPP_P0PPCR_BSM_1_4 0x2
> +#define DCMIPP_P0PPCR_BSM_2_4 0x3
> +#define DCMIPP_P0PPCR_BSM_MASK GENMASK(8, 7)
> +#define DCMIPP_P0PPCR_BSM_SHIFT 0x7
> +#define DCMIPP_P0PPCR_LSM BIT(10)
> +#define DCMIPP_P0PPCR_OELS BIT(11)

It'd be nice to align the macro values.

> +
> +#define IS_SINK(pad) (!(pad))
> +#define IS_SRC(pad) ((pad))

It'd be nicer to have macros for the pads, e.g. DCIMPP_PAD_SINK, and use
them instead of opaque IS_SRC and IS_SINK.

> +#define PAD_STR(pad) (IS_SRC((pad))) ? "src" : "sink"

PAD_STR is unused.

> +
> +#define BYTEPROC_MEDIA_BUS_FMT_DEFAULT MEDIA_BUS_FMT_RGB565_2X8_LE

It'd be better to use plain MEDIA_BUS_FMT_RGB565_2X8_LE instead.

> +
> +struct dcmipp_byteproc_pix_map {
> + unsigned int code;
> + unsigned int bpp;
> +};
> +
> +#define PIXMAP_MBUS_BPP(mbus, byteperpixel) \
> + { \
> + .code = MEDIA_BUS_FMT_##mbus, \
> + .bpp = byteperpixel, \
> + }
> +static const struct dcmipp_byteproc_pix_map dcmipp_byteproc_pix_map_list[] = {
> + PIXMAP_MBUS_BPP(RGB565_2X8_LE, 2),
> + PIXMAP_MBUS_BPP(YUYV8_2X8, 2),
> + PIXMAP_MBUS_BPP(YVYU8_2X8, 2),
> + PIXMAP_MBUS_BPP(UYVY8_2X8, 2),
> + PIXMAP_MBUS_BPP(VYUY8_2X8, 2),
> + PIXMAP_MBUS_BPP(Y8_1X8, 1),
> + PIXMAP_MBUS_BPP(SBGGR8_1X8, 1),
> + PIXMAP_MBUS_BPP(SGBRG8_1X8, 1),
> + PIXMAP_MBUS_BPP(SGRBG8_1X8, 1),
> + PIXMAP_MBUS_BPP(SRGGB8_1X8, 1),
> + PIXMAP_MBUS_BPP(JPEG_1X8, 1),
> +};
> +
> +static const struct dcmipp_byteproc_pix_map *dcmipp_byteproc_pix_map_by_index(unsigned int i)

This has one use only, please move it to where it is called.

> +{
> + const struct dcmipp_byteproc_pix_map *l = dcmipp_byteproc_pix_map_list;
> + unsigned int size = ARRAY_SIZE(dcmipp_byteproc_pix_map_list);

size is redundant, please use ARRAY_SIZE() below instead.

Same for l.

> +
> + if (i >= size)
> + return NULL;
> +
> + return &l[i];
> +}
> +
> +static const struct dcmipp_byteproc_pix_map *dcmipp_byteproc_pix_map_by_code(u32 code)
> +{
> + const struct dcmipp_byteproc_pix_map *l = dcmipp_byteproc_pix_map_list;
> + unsigned int size = ARRAY_SIZE(dcmipp_byteproc_pix_map_list);
> + unsigned int i;
> +
> + for (i = 0; i < size; i++) {
> + if (l[i].code == code)
> + return &l[i];
> + }
> +
> + return NULL;
> +}
> +
> +struct dcmipp_byteproc_device {
> + struct dcmipp_ent_device ved;
> + struct v4l2_subdev sd;
> + struct device *dev;
> + struct v4l2_mbus_framefmt sink_fmt;
> + bool streaming;
> + /* Protect this data structure */
> + struct mutex lock;
> +
> + void __iomem *regs;
> +
> + struct v4l2_fract sink_interval;
> + struct v4l2_fract src_interval;
> + unsigned int frate;
> + u32 src_code;
> + struct v4l2_rect crop;
> + struct v4l2_rect compose;
> +};
> +
> +static const struct v4l2_mbus_framefmt fmt_default = {
> + .width = DCMIPP_FMT_WIDTH_DEFAULT,
> + .height = DCMIPP_FMT_HEIGHT_DEFAULT,
> + .code = BYTEPROC_MEDIA_BUS_FMT_DEFAULT,
> + .field = V4L2_FIELD_NONE,
> + .colorspace = DCMIPP_COLORSPACE_DEFAULT,
> + .ycbcr_enc = DCMIPP_YCBCR_ENC_DEFAULT,
> + .quantization = DCMIPP_QUANTIZATION_DEFAULT,
> + .xfer_func = DCMIPP_XFER_FUNC_DEFAULT,
> +};
> +
> +static const struct v4l2_rect crop_min = {
> + .width = DCMIPP_FRAME_MIN_WIDTH,
> + .height = DCMIPP_FRAME_MIN_HEIGHT,
> + .top = 0,
> + .left = 0,
> +};
> +
> +static struct v4l2_rect
> +dcmipp_byteproc_get_compose_bound(const struct v4l2_mbus_framefmt *fmt)

One user only, please move the code to the call site.

> +{
> + /* Get the crop bounds to clamp the crop rectangle correctly */
> + struct v4l2_rect r = {
> + .left = 0,
> + .top = 0,
> + .width = fmt->width,
> + .height = fmt->height,
> + };
> +
> + return r;
> +}
> +
> +static void dcmipp_byteproc_adjust_crop(struct v4l2_rect *r, struct v4l2_rect *compose)
> +{
> + /* Disallow rectangles smaller than the minimal one. */
> + v4l2_rect_set_min_size(r, &crop_min);
> + v4l2_rect_map_inside(r, compose);
> +}
> +
> +static void dcmipp_byteproc_adjust_compose(struct v4l2_rect *r,
> + const struct v4l2_mbus_framefmt *fmt)
> +{
> + r->top = 0;
> + r->left = 0;
> +
> + /* Compose is not possible for JPEG or Bayer formats */
> + if (fmt->code == MEDIA_BUS_FMT_JPEG_1X8 ||
> + fmt->code == MEDIA_BUS_FMT_SBGGR8_1X8 || fmt->code == MEDIA_BUS_FMT_SGBRG8_1X8 ||
> + fmt->code == MEDIA_BUS_FMT_SGRBG8_1X8 || fmt->code == MEDIA_BUS_FMT_SRGGB8_1X8) {
> + r->width = fmt->width;
> + r->height = fmt->height;
> + return;
> + }
> +
> + /* Adjust height - we can only perform 1/2 decimation */
> + if (r->height <= (fmt->height / 2))
> + r->height = fmt->height / 2;
> + else
> + r->height = fmt->height;
> +
> + /* Adjust width - /2 or /4 for 8bits formats and /2 for 16bits formats */
> + if (fmt->code == MEDIA_BUS_FMT_Y8_1X8 && r->width <= (fmt->width / 4))
> + r->width = fmt->width / 4;
> + else if (r->width <= (fmt->width / 2))
> + r->width = fmt->width / 2;
> + else
> + r->width = fmt->width;
> +}
> +
> +static void dcmipp_byteproc_adjust_fmt(struct v4l2_mbus_framefmt *fmt)
> +{
> + const struct dcmipp_byteproc_pix_map *vpix;
> +
> + /* Only accept code in the pix map table */
> + vpix = dcmipp_byteproc_pix_map_by_code(fmt->code);
> + if (!vpix)
> + fmt->code = fmt_default.code;
> +
> + fmt->width = clamp_t(u32, fmt->width, DCMIPP_FRAME_MIN_WIDTH,
> + DCMIPP_FRAME_MAX_WIDTH) & ~1;
> + fmt->height = clamp_t(u32, fmt->height, DCMIPP_FRAME_MIN_HEIGHT,
> + DCMIPP_FRAME_MAX_HEIGHT) & ~1;
> +
> + if (fmt->field == V4L2_FIELD_ANY || fmt->field == V4L2_FIELD_ALTERNATE)
> + fmt->field = fmt_default.field;
> +
> + dcmipp_colorimetry_clamp(fmt);
> +}
> +
> +static int dcmipp_byteproc_init_cfg(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state)
> +{
> + unsigned int i;
> +
> + for (i = 0; i < sd->entity.num_pads; i++) {
> + struct v4l2_mbus_framefmt *mf;
> + struct v4l2_rect *r;
> +
> + mf = v4l2_subdev_get_try_format(sd, sd_state, i);
> + *mf = fmt_default;
> +
> + if (IS_SINK(i))
> + r = v4l2_subdev_get_try_compose(sd, sd_state, i);
> + else
> + r = v4l2_subdev_get_try_crop(sd, sd_state, i);
> +
> + r->top = 0;
> + r->left = 0;
> + r->width = DCMIPP_FMT_WIDTH_DEFAULT;
> + r->height = DCMIPP_FMT_HEIGHT_DEFAULT;
> + }
> +
> + return 0;
> +}
> +
> +static int dcmipp_byteproc_enum_mbus_code(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state,
> + struct v4l2_subdev_mbus_code_enum *code)
> +{
> + const struct dcmipp_byteproc_pix_map *vpix;
> +
> + vpix = dcmipp_byteproc_pix_map_by_index(code->index);
> + if (!vpix)
> + return -EINVAL;
> +
> + code->code = vpix->code;
> +
> + return 0;
> +}
> +
> +static int dcmipp_byteproc_enum_frame_size(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state,
> + struct v4l2_subdev_frame_size_enum *fse)
> +{
> + const struct dcmipp_byteproc_pix_map *vpix;
> +
> + if (fse->index)
> + return -EINVAL;
> +
> + /* Only accept code in the pix map table */
> + vpix = dcmipp_byteproc_pix_map_by_code(fse->code);
> + if (!vpix)
> + return -EINVAL;
> +
> + fse->min_width = DCMIPP_FRAME_MIN_WIDTH;
> + fse->max_width = DCMIPP_FRAME_MAX_WIDTH;
> + fse->min_height = DCMIPP_FRAME_MIN_HEIGHT;
> + fse->max_height = DCMIPP_FRAME_MAX_HEIGHT;
> +
> + return 0;
> +}
> +
> +static int dcmipp_byteproc_get_fmt(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state,
> + struct v4l2_subdev_format *fmt)
> +{
> + struct dcmipp_byteproc_device *byteproc = v4l2_get_subdevdata(sd);
> + struct v4l2_rect *crop_rect;
> +
> + mutex_lock(&byteproc->lock);
> +
> + if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
> + fmt->format = *v4l2_subdev_get_try_format(sd, sd_state, 0);
> + crop_rect = v4l2_subdev_get_try_crop(sd, sd_state, 1);
> + } else {
> + fmt->format = byteproc->sink_fmt;
> + crop_rect = &byteproc->crop;
> + }
> +
> + if (IS_SRC(fmt->pad)) {
> + fmt->format.width = crop_rect->width;
> + fmt->format.height = crop_rect->height;
> + }
> +
> + mutex_unlock(&byteproc->lock);
> +
> + return 0;
> +}
> +
> +static int dcmipp_byteproc_set_fmt(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state,
> + struct v4l2_subdev_format *fmt)
> +{
> + struct dcmipp_byteproc_device *byteproc = v4l2_get_subdevdata(sd);
> + struct v4l2_mbus_framefmt *sink_fmt;
> + struct v4l2_rect *crop, *compose;
> + int ret = 0;
> +
> + mutex_lock(&byteproc->lock);
> +
> + if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
> + if (byteproc->streaming) {
> + ret = -EBUSY;
> + goto out;
> + }
> +
> + sink_fmt = &byteproc->sink_fmt;
> + crop = &byteproc->crop;
> + compose = &byteproc->compose;
> + } else {
> + sink_fmt = v4l2_subdev_get_try_format(sd, sd_state, 0);
> + crop = v4l2_subdev_get_try_crop(sd, sd_state, 1);
> + compose = v4l2_subdev_get_try_compose(sd, sd_state, 0);
> + }
> +
> + if (IS_SRC(fmt->pad)) {
> + fmt->format = *sink_fmt;
> + fmt->format.width = crop->width;
> + fmt->format.height = crop->height;
> + } else {
> + dcmipp_byteproc_adjust_fmt(&fmt->format);
> + crop->top = 0;
> + crop->left = 0;
> + crop->width = fmt->format.width;
> + crop->height = fmt->format.height;
> + *compose = *crop;
> + *sink_fmt = fmt->format;
> + }
> +
> +out:
> + mutex_unlock(&byteproc->lock);
> +
> + return ret;
> +}
> +
> +static int dcmipp_byteproc_get_selection(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state,
> + struct v4l2_subdev_selection *s)
> +{
> + struct dcmipp_byteproc_device *byteproc = v4l2_get_subdevdata(sd);
> + struct v4l2_mbus_framefmt *sink_fmt;
> + struct v4l2_rect *crop, *compose;
> +
> + /*
> + * In the HW, the decimation block is located prior to the crop hence:
> + * Compose is done on the sink pad
> + * Crop is done on the src pad
> + */
> + if ((s->target == V4L2_SEL_TGT_CROP ||
> + s->target == V4L2_SEL_TGT_CROP_BOUNDS ||
> + s->target == V4L2_SEL_TGT_CROP_DEFAULT) && IS_SINK(s->pad))

Check the pad first, not the target. Same below.

> + return -EINVAL;
> +
> + if ((s->target == V4L2_SEL_TGT_COMPOSE ||
> + s->target == V4L2_SEL_TGT_COMPOSE_BOUNDS ||
> + s->target == V4L2_SEL_TGT_COMPOSE_DEFAULT) && IS_SRC(s->pad))
> + return -EINVAL;
> +
> + if (s->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
> + sink_fmt = &byteproc->sink_fmt;
> + crop = &byteproc->crop;
> + compose = &byteproc->compose;
> + } else {
> + sink_fmt = v4l2_subdev_get_try_format(sd, sd_state, 0);
> + crop = v4l2_subdev_get_try_crop(sd, sd_state, 1);
> + compose = v4l2_subdev_get_try_compose(sd, sd_state, 0);
> + }
> +
> + switch (s->target) {
> + case V4L2_SEL_TGT_CROP:
> + s->r = *crop;
> + break;
> + case V4L2_SEL_TGT_CROP_BOUNDS:
> + case V4L2_SEL_TGT_CROP_DEFAULT:
> + s->r = *compose;
> + break;
> + case V4L2_SEL_TGT_COMPOSE:
> + s->r = *compose;
> + break;
> + case V4L2_SEL_TGT_COMPOSE_BOUNDS:
> + s->r = dcmipp_byteproc_get_compose_bound(sink_fmt);
> + break;
> + case V4L2_SEL_TGT_COMPOSE_DEFAULT:
> + s->r.top = 0;
> + s->r.left = 0;
> + s->r.width = sink_fmt->width;
> + s->r.height = sink_fmt->height;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static int dcmipp_byteproc_set_selection(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state,
> + struct v4l2_subdev_selection *s)
> +{
> + struct dcmipp_byteproc_device *byteproc = v4l2_get_subdevdata(sd);
> + struct v4l2_mbus_framefmt *sink_fmt;
> + struct v4l2_rect *crop, *compose;
> +
> + /*
> + * In the HW, the decimation block is located prior to the crop hence:
> + * Compose is done on the sink pad
> + * Crop is done on the src pad
> + */
> + if ((s->target == V4L2_SEL_TGT_CROP ||
> + s->target == V4L2_SEL_TGT_CROP_BOUNDS ||
> + s->target == V4L2_SEL_TGT_CROP_DEFAULT) && IS_SINK(s->pad))
> + return -EINVAL;
> +
> + if ((s->target == V4L2_SEL_TGT_COMPOSE ||
> + s->target == V4L2_SEL_TGT_COMPOSE_BOUNDS ||
> + s->target == V4L2_SEL_TGT_COMPOSE_DEFAULT) && IS_SRC(s->pad))
> + return -EINVAL;
> +
> + if (s->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
> + sink_fmt = &byteproc->sink_fmt;
> + crop = &byteproc->crop;
> + compose = &byteproc->compose;
> + } else {
> + sink_fmt = v4l2_subdev_get_try_format(sd, sd_state, 0);
> + crop = v4l2_subdev_get_try_crop(sd, sd_state, 1);
> + compose = v4l2_subdev_get_try_compose(sd, sd_state, 0);
> + }
> +
> + switch (s->target) {
> + case V4L2_SEL_TGT_CROP:
> + dcmipp_byteproc_adjust_crop(&s->r, compose);
> +
> + *crop = s->r;
> +
> + dev_dbg(byteproc->dev, "s_selection: crop %ux%u@(%u,%u)\n",
> + crop->width, crop->height, crop->left, crop->top);
> + break;
> + case V4L2_SEL_TGT_COMPOSE:
> + dcmipp_byteproc_adjust_compose(&s->r, sink_fmt);
> + *compose = s->r;
> + *crop = s->r;
> +
> + dev_dbg(byteproc->dev, "s_selection: compose %ux%u@(%u,%u)\n",
> + compose->width, compose->height, compose->left, compose->top);
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static const unsigned int dcmipp_frates[] = {1, 2, 4, 8};
> +
> +static int dcmipp_byteproc_enum_frame_interval
> + (struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state,
> + struct v4l2_subdev_frame_interval_enum *fie)
> +{
> + struct dcmipp_byteproc_device *byteproc = v4l2_get_subdevdata(sd);
> + struct v4l2_fract *sink_interval = &byteproc->sink_interval;
> + unsigned int ratio;
> + int ret = 0;
> +
> + if (fie->pad > 1 ||
> + fie->index >= (IS_SRC(fie->pad) ? ARRAY_SIZE(dcmipp_frates) : 1) ||
> + fie->width > DCMIPP_FRAME_MAX_WIDTH ||
> + fie->height > DCMIPP_FRAME_MAX_HEIGHT)
> + return -EINVAL;
> +
> + mutex_lock(&byteproc->lock);
> +
> + if (IS_SINK(fie->pad)) {
> + fie->interval = *sink_interval;
> + goto out;
> + }
> +
> + ratio = dcmipp_frates[fie->index];

How does ratio work? Drop every n'th frame?

> +
> + fie->interval.numerator = sink_interval->numerator * ratio;
> + fie->interval.denominator = sink_interval->denominator;
> +
> +out:
> + mutex_unlock(&byteproc->lock);
> + return ret;
> +}
> +
> +static const struct v4l2_subdev_pad_ops dcmipp_byteproc_pad_ops = {
> + .init_cfg = dcmipp_byteproc_init_cfg,
> + .enum_mbus_code = dcmipp_byteproc_enum_mbus_code,
> + .enum_frame_size = dcmipp_byteproc_enum_frame_size,
> + .enum_frame_interval = dcmipp_byteproc_enum_frame_interval,
> + .get_fmt = dcmipp_byteproc_get_fmt,
> + .set_fmt = dcmipp_byteproc_set_fmt,
> + .get_selection = dcmipp_byteproc_get_selection,
> + .set_selection = dcmipp_byteproc_set_selection,
> +};
> +
> +static int dcmipp_byteproc_configure_scale_crop
> + (struct dcmipp_byteproc_device *byteproc)
> +{
> + const struct dcmipp_byteproc_pix_map *vpix;
> + u32 hprediv, vprediv;
> + struct v4l2_rect *crop = &byteproc->crop;
> + u32 val = 0;
> +
> + /* find output format bpp */
> + vpix = dcmipp_byteproc_pix_map_by_code(byteproc->sink_fmt.code);
> + if (!vpix)
> + return -EINVAL;
> +
> + /* clear decimation/crop */
> + reg_clear(byteproc, DCMIPP_P0PPCR, DCMIPP_P0PPCR_BSM_MASK);
> + reg_clear(byteproc, DCMIPP_P0PPCR, DCMIPP_P0PPCR_LSM);
> + reg_write(byteproc, DCMIPP_P0SCSTR, 0);
> + reg_write(byteproc, DCMIPP_P0SCSZR, 0);
> +
> + /* Ignore decimation/crop with JPEG */
> + if (vpix->code == MEDIA_BUS_FMT_JPEG_1X8)
> + return 0;
> +
> + /* decimation */
> + hprediv = byteproc->sink_fmt.width / byteproc->compose.width;
> + if (hprediv == 4)
> + val |= DCMIPP_P0PPCR_BSM_1_4 << DCMIPP_P0PPCR_BSM_SHIFT;
> + else if ((vpix->code == MEDIA_BUS_FMT_Y8_1X8) && (hprediv == 2))
> + val |= DCMIPP_P0PPCR_BSM_1_2 << DCMIPP_P0PPCR_BSM_SHIFT;
> + else if (hprediv == 2)
> + val |= DCMIPP_P0PPCR_BSM_2_4 << DCMIPP_P0PPCR_BSM_SHIFT;
> +
> + vprediv = byteproc->sink_fmt.height / byteproc->compose.height;
> + if (vprediv == 2)
> + val |= DCMIPP_P0PPCR_LSM | DCMIPP_P0PPCR_OELS;
> +
> + /* decimate using bytes and lines skipping */
> + if (val) {
> + reg_set(byteproc, DCMIPP_P0PPCR, val);
> +
> + dev_dbg(byteproc->dev, "decimate to %dx%d [prediv=%dx%d]\n",
> + byteproc->compose.width, byteproc->compose.height, hprediv, vprediv);
> + }
> +
> + dev_dbg(byteproc->dev, "crop to %dx%d\n", crop->width, crop->height);
> +
> + /* expressed in 32-bits words on X axis, lines on Y axis */
> + reg_write(byteproc, DCMIPP_P0SCSTR,
> + (((crop->left * vpix->bpp) / 4) << DCMIPP_P0SCSTR_HSTART_SHIFT) |
> + (crop->top << DCMIPP_P0SCSTR_VSTART_SHIFT));
> + reg_write(byteproc, DCMIPP_P0SCSZR,
> + DCMIPP_P0SCSZR_ENABLE |
> + (((crop->width * vpix->bpp) / 4) << DCMIPP_P0SCSZR_HSIZE_SHIFT) |
> + (crop->height << DCMIPP_P0SCSZR_VSIZE_SHIFT));
> +
> + return 0;
> +}
> +
> +static void dcmipp_byteproc_configure_framerate
> + (struct dcmipp_byteproc_device *byteproc)
> +{
> + /* Frame skipping */
> + reg_clear(byteproc, DCMIPP_P0FCTCR, DCMIPP_P0FCTCR_FRATE_MASK);
> + reg_set(byteproc, DCMIPP_P0FCTCR, byteproc->frate);
> +}
> +
> +static int dcmipp_byteproc_g_frame_interval(struct v4l2_subdev *sd,
> + struct v4l2_subdev_frame_interval *fi)
> +{
> + struct dcmipp_byteproc_device *byteproc = v4l2_get_subdevdata(sd);
> +
> + if (IS_SINK(fi->pad))
> + fi->interval = byteproc->sink_interval;
> + else
> + fi->interval = byteproc->src_interval;
> +
> + return 0;
> +}
> +
> +static int dcmipp_byteproc_s_frame_interval(struct v4l2_subdev *sd,
> + struct v4l2_subdev_frame_interval *fi)
> +{
> + struct dcmipp_byteproc_device *byteproc = v4l2_get_subdevdata(sd);
> +
> + mutex_lock(&byteproc->lock);
> +
> + if (byteproc->streaming) {
> + mutex_unlock(&byteproc->lock);
> + return -EBUSY;
> + }
> +
> + if (fi->interval.numerator == 0 || fi->interval.denominator == 0)
> + fi->interval = byteproc->sink_interval;
> +
> + if (IS_SINK(fi->pad)) {
> + /*
> + * Setting sink frame interval resets frame skipping.
> + * Sink frame interval is propagated to src.
> + */
> + byteproc->frate = 0;
> + byteproc->sink_interval = fi->interval;
> + byteproc->src_interval = byteproc->sink_interval;

Is this used for anything else than configure skipping?

I think I'd just have a control for it in that case.

I don't think exposing frame interval configuration is necessarily even
meaningful for a device that just processes data but does not produce it.

> + } else {
> + unsigned int ratio;
> +
> + /* Normalize ratio */
> + ratio = (byteproc->sink_interval.denominator *
> + fi->interval.numerator) /
> + (byteproc->sink_interval.numerator *
> + fi->interval.denominator);
> +
> + /* Hardware can skip 1 frame over 2, 4 or 8 */
> + byteproc->frate = ratio >= 8 ? 3 :
> + ratio >= 4 ? 2 :
> + ratio >= 2 ? 1 : 0;
> +
> + /* Adjust src frame interval to what hardware can really do */
> + byteproc->src_interval.numerator =
> + byteproc->sink_interval.numerator * ratio;
> + byteproc->src_interval.denominator =
> + byteproc->sink_interval.denominator;
> + }
> +
> + mutex_unlock(&byteproc->lock);
> +
> + return 0;
> +}
> +
> +#define STOP_TIMEOUT_US 1000
> +#define POLL_INTERVAL_US 50
> +static int dcmipp_byteproc_s_stream(struct v4l2_subdev *sd, int enable)
> +{
> + struct dcmipp_byteproc_device *byteproc = v4l2_get_subdevdata(sd);
> + int ret = 0;
> +
> + mutex_lock(&byteproc->lock);
> + if (enable) {
> + dcmipp_byteproc_configure_framerate(byteproc);
> +
> + ret = dcmipp_byteproc_configure_scale_crop(byteproc);
> + if (ret)
> + goto err;

This does nothing.

> + }
> +
> +err:
> + mutex_unlock(&byteproc->lock);
> +
> + return ret;
> +}
> +
> +static const struct v4l2_subdev_video_ops dcmipp_byteproc_video_ops = {
> + .g_frame_interval = dcmipp_byteproc_g_frame_interval,
> + .s_frame_interval = dcmipp_byteproc_s_frame_interval,
> + .s_stream = dcmipp_byteproc_s_stream,
> +};
> +
> +static const struct v4l2_subdev_ops dcmipp_byteproc_ops = {
> + .pad = &dcmipp_byteproc_pad_ops,
> + .video = &dcmipp_byteproc_video_ops,
> +};
> +
> +/* FIXME */
> +static void dcmipp_byteproc_release(struct v4l2_subdev *sd)
> +{
> + struct dcmipp_byteproc_device *byteproc = v4l2_get_subdevdata(sd);
> +
> + kfree(byteproc);
> +}
> +
> +static const struct v4l2_subdev_internal_ops dcmipp_byteproc_int_ops = {
> + .release = dcmipp_byteproc_release,
> +};
> +
> +static void dcmipp_byteproc_comp_unbind(struct device *comp,
> + struct device *master,
> + void *master_data)
> +{
> + struct dcmipp_ent_device *ved = dev_get_drvdata(comp);
> + struct dcmipp_byteproc_device *byteproc =
> + container_of(ved, struct dcmipp_byteproc_device, ved);
> +
> + dcmipp_ent_sd_unregister(ved, &byteproc->sd);
> +}
> +
> +static int dcmipp_byteproc_comp_bind(struct device *comp, struct device *master,
> + void *master_data)
> +{
> + struct dcmipp_bind_data *bind_data = master_data;
> + struct dcmipp_platform_data *pdata = comp->platform_data;
> + struct dcmipp_byteproc_device *byteproc;
> + struct v4l2_rect r = {
> + .top = 0,
> + .left = 0,
> + .width = DCMIPP_FMT_WIDTH_DEFAULT,
> + .height = DCMIPP_FMT_HEIGHT_DEFAULT,
> + };
> + struct v4l2_fract interval = {
> + .numerator = 1,
> + .denominator = 30,
> + };
> + int ret;
> +
> + /* Allocate the byteproc struct */
> + byteproc = kzalloc(sizeof(*byteproc), GFP_KERNEL);
> + if (!byteproc)
> + return -ENOMEM;
> +
> + byteproc->regs = bind_data->regs;
> +
> + /* Initialize the lock */
> + mutex_init(&byteproc->lock);
> +
> + /* Initialize ved and sd */
> + ret = dcmipp_ent_sd_register(&byteproc->ved, &byteproc->sd,
> + bind_data->v4l2_dev,
> + pdata->entity_name,
> + MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER, 2,
> + (const unsigned long[2]) {
> + MEDIA_PAD_FL_SINK,
> + MEDIA_PAD_FL_SOURCE,
> + },
> + &dcmipp_byteproc_int_ops,
> + &dcmipp_byteproc_ops,
> + NULL, NULL);
> + if (ret) {
> + kfree(byteproc);
> + return ret;
> + }
> +
> + dev_set_drvdata(comp, &byteproc->ved);
> + byteproc->dev = comp;
> +
> + /* Initialize the frame format */
> + byteproc->sink_fmt = fmt_default;
> + byteproc->crop = r;
> + byteproc->compose = r;
> + byteproc->src_interval = interval;
> + byteproc->sink_interval = interval;
> +
> + return 0;
> +}
> +
> +static const struct component_ops dcmipp_byteproc_comp_ops = {
> + .bind = dcmipp_byteproc_comp_bind,
> + .unbind = dcmipp_byteproc_comp_unbind,
> +};
> +
> +static int dcmipp_byteproc_probe(struct platform_device *pdev)
> +{
> + return component_add(&pdev->dev, &dcmipp_byteproc_comp_ops);
> +}
> +
> +static int dcmipp_byteproc_remove(struct platform_device *pdev)
> +{
> + component_del(&pdev->dev, &dcmipp_byteproc_comp_ops);
> +
> + return 0;
> +}
> +
> +static const struct platform_device_id dcmipp_byteproc_driver_ids[] = {
> + {
> + .name = DCMIPP_BYTEPROC_DRV_NAME,
> + },
> + { }
> +};
> +
> +static struct platform_driver dcmipp_byteproc_pdrv = {
> + .probe = dcmipp_byteproc_probe,
> + .remove = dcmipp_byteproc_remove,
> + .id_table = dcmipp_byteproc_driver_ids,
> + .driver = {
> + .name = DCMIPP_BYTEPROC_DRV_NAME,
> + },
> +};
> +
> +module_platform_driver(dcmipp_byteproc_pdrv);
> +
> +MODULE_DEVICE_TABLE(platform, dcmipp_byteproc_driver_ids);
> +
> +MODULE_AUTHOR("Hugues Fruchet <hugues.fruchet@xxxxxxxxxxx>");
> +MODULE_AUTHOR("Alain Volmat <alain.volmat@xxxxxxxxxxx>");
> +MODULE_DESCRIPTION("STMicroelectronics STM32 Digital Camera Memory Interface with Pixel Processor driver");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-common.c b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-common.c
> new file mode 100644
> index 000000000000..f070690ccbb1
> --- /dev/null
> +++ b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-common.c
> @@ -0,0 +1,116 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for STM32 Digital Camera Memory Interface Pixel Processor
> + *
> + * Copyright (C) STMicroelectronics SA 2022
> + * Authors: Hugues Fruchet <hugues.fruchet@xxxxxxxxxxx>
> + * Alain Volmat <alain.volmat@xxxxxxxxxxx>
> + * for STMicroelectronics.
> + */
> +
> +#include <linux/init.h>
> +#include <linux/module.h>
> +
> +#include "dcmipp-common.h"
> +
> +/* Helper function to allocate and initialize pads */
> +struct media_pad *dcmipp_pads_init(u16 num_pads, const unsigned long *pads_flag)
> +{
> + struct media_pad *pads;
> + unsigned int i;
> +
> + /* Allocate memory for the pads */
> + pads = kcalloc(num_pads, sizeof(*pads), GFP_KERNEL);
> + if (!pads)
> + return ERR_PTR(-ENOMEM);
> +
> + /* Initialize the pads */
> + for (i = 0; i < num_pads; i++) {
> + pads[i].index = i;
> + pads[i].flags = pads_flag[i];
> + }
> +
> + return pads;
> +}
> +EXPORT_SYMBOL_GPL(dcmipp_pads_init);
> +
> +int dcmipp_link_validate(struct media_link *link)
> +{
> + /* TODO */
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(dcmipp_link_validate);
> +
> +static const struct media_entity_operations dcmipp_ent_sd_mops = {
> + .link_validate = dcmipp_link_validate,
> +};
> +
> +int dcmipp_ent_sd_register(struct dcmipp_ent_device *ved,
> + struct v4l2_subdev *sd,
> + struct v4l2_device *v4l2_dev,
> + const char *const name,
> + u32 function,
> + u16 num_pads,
> + const unsigned long *pads_flag,
> + const struct v4l2_subdev_internal_ops *sd_int_ops,
> + const struct v4l2_subdev_ops *sd_ops,
> + irq_handler_t handler,
> + irq_handler_t thread_fn)
> +{
> + int ret;
> +
> + /* Allocate the pads. Should be released from the sd_int_op release */
> + ved->pads = dcmipp_pads_init(num_pads, pads_flag);
> + if (IS_ERR(ved->pads))
> + return PTR_ERR(ved->pads);
> +
> + /* Fill the dcmipp_ent_device struct */
> + ved->ent = &sd->entity;
> +
> + /* Initialize the subdev */
> + v4l2_subdev_init(sd, sd_ops);
> + sd->internal_ops = sd_int_ops;
> + sd->entity.function = function;
> + sd->entity.ops = &dcmipp_ent_sd_mops;
> + sd->owner = THIS_MODULE;
> + strscpy(sd->name, name, sizeof(sd->name));
> + v4l2_set_subdevdata(sd, ved);
> +
> + /* Expose this subdev to user space */
> + sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> + if (sd->ctrl_handler)
> + sd->flags |= V4L2_SUBDEV_FL_HAS_EVENTS;
> +
> + /* Initialize the media entity */
> + ret = media_entity_pads_init(&sd->entity, num_pads, ved->pads);
> + if (ret)
> + goto err_clean_pads;
> +
> + /* Register the subdev with the v4l2 and the media framework */
> + ret = v4l2_device_register_subdev(v4l2_dev, sd);
> + if (ret) {
> + dev_err(v4l2_dev->dev,
> + "%s: subdev register failed (err=%d)\n",
> + name, ret);
> + goto err_clean_m_ent;
> + }
> +
> + ved->handler = handler;
> + ved->thread_fn = thread_fn;
> +
> + return 0;
> +
> +err_clean_m_ent:
> + media_entity_cleanup(&sd->entity);
> +err_clean_pads:
> + dcmipp_pads_cleanup(ved->pads);
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(dcmipp_ent_sd_register);
> +
> +void dcmipp_ent_sd_unregister(struct dcmipp_ent_device *ved, struct v4l2_subdev *sd)
> +{
> + media_entity_cleanup(ved->ent);
> + v4l2_device_unregister_subdev(sd);
> +}
> +EXPORT_SYMBOL_GPL(dcmipp_ent_sd_unregister);
> diff --git a/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-common.h b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-common.h
> new file mode 100644
> index 000000000000..a8c162193de6
> --- /dev/null
> +++ b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-common.h
> @@ -0,0 +1,240 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * Driver for STM32 Digital Camera Memory Interface Pixel Processor
> + *
> + * Copyright (C) STMicroelectronics SA 2022
> + * Authors: Hugues Fruchet <hugues.fruchet@xxxxxxxxxxx>
> + * Alain Volmat <alain.volmat@xxxxxxxxxxx>
> + * for STMicroelectronics.
> + */
> +
> +#ifndef _DCMIPP_COMMON_H_
> +#define _DCMIPP_COMMON_H_
> +
> +#include <linux/interrupt.h>
> +#include <linux/slab.h>
> +#include <media/media-device.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-fwnode.h>
> +
> +#define DCMIPP_PDEV_NAME "dcmipp"
> +
> +/* DCMIPP-specific controls */
> +#define DCMIPP_CID_DCMIPP_BASE (0x00f00000 | 0xf000)
> +#define DCMIPP_CID_DCMIPP_CLASS (0x00f00000 | 1)
> +#define DCMIPP_CID_TEST_PATTERN (DCMIPP_CID_DCMIPP_BASE + 0)
> +
> +#define DCMIPP_FRAME_MAX_WIDTH 4096
> +#define DCMIPP_FRAME_MAX_HEIGHT 2160
> +#define DCMIPP_FRAME_MIN_WIDTH 16
> +#define DCMIPP_FRAME_MIN_HEIGHT 16
> +
> +#define DCMIPP_FMT_WIDTH_DEFAULT 640
> +#define DCMIPP_FMT_HEIGHT_DEFAULT 480
> +
> +#define DCMIPP_FRAME_INDEX(lin, col, width, bpp) \
> + (((lin) * (width) + (col)) * (bpp))
> +
> +#define DCMIPP_COLORSPACE_DEFAULT V4L2_COLORSPACE_REC709
> +#define DCMIPP_YCBCR_ENC_DEFAULT V4L2_YCBCR_ENC_DEFAULT
> +#define DCMIPP_QUANTIZATION_DEFAULT V4L2_QUANTIZATION_DEFAULT
> +#define DCMIPP_XFER_FUNC_DEFAULT V4L2_XFER_FUNC_DEFAULT
> +
> +/**
> + * struct dcmipp_colorimetry_clamp - Adjust colorimetry parameters
> + *
> + * @fmt: the pointer to struct v4l2_pix_format or
> + * struct v4l2_mbus_framefmt
> + *
> + * Entities must check if colorimetry given by the userspace is valid, if not
> + * then set them as DEFAULT
> + */
> +#define dcmipp_colorimetry_clamp(fmt) \
> +do { \
> + if ((fmt)->colorspace == V4L2_COLORSPACE_DEFAULT || \
> + (fmt)->colorspace > V4L2_COLORSPACE_DCI_P3) { \
> + (fmt)->colorspace = DCMIPP_COLORSPACE_DEFAULT; \
> + (fmt)->ycbcr_enc = DCMIPP_YCBCR_ENC_DEFAULT; \
> + (fmt)->quantization = DCMIPP_QUANTIZATION_DEFAULT; \
> + (fmt)->xfer_func = DCMIPP_XFER_FUNC_DEFAULT; \
> + } \
> + if ((fmt)->ycbcr_enc > V4L2_YCBCR_ENC_SMPTE240M) \
> + (fmt)->ycbcr_enc = DCMIPP_YCBCR_ENC_DEFAULT; \
> + if ((fmt)->quantization > V4L2_QUANTIZATION_LIM_RANGE) \
> + (fmt)->quantization = DCMIPP_QUANTIZATION_DEFAULT; \
> + if ((fmt)->xfer_func > V4L2_XFER_FUNC_SMPTE2084) \
> + (fmt)->xfer_func = DCMIPP_XFER_FUNC_DEFAULT; \
> +} while (0)
> +
> +/**
> + * struct dcmipp_platform_data - platform data to components
> + *
> + * @entity_name: The name of the entity to be created
> + *
> + * Board setup code will often provide additional information using the device's
> + * platform_data field to hold additional information.
> + * When injecting a new platform_device in the component system the core needs
> + * to provide to the corresponding submodules the name of the entity that should
> + * be used when registering the subdevice in the Media Controller system.
> + */
> +struct dcmipp_platform_data {
> + char entity_name[32];
> +};
> +
> +struct dcmipp_bind_data {
> + /* Internal v4l2 parent device*/
> + struct v4l2_device *v4l2_dev;
> +
> + /* Hardware resources */
> + struct reset_control *rstc;
> + void __iomem *regs;
> +};
> +
> +/**
> + * struct dcmipp_ent_device - core struct that represents a node in the topology
> + *
> + * @ent: the pointer to struct media_entity for the node
> + * @pads: the list of pads of the node
> + * @process_frame: callback send a frame to that node
> + * @vdev_get_format: callback that returns the current format a pad, used
> + * only when is_media_entity_v4l2_video_device(ent) returns
> + * true
> + *
> + * Each node of the topology must create a dcmipp_ent_device struct. Depending on
> + * the node it will be of an instance of v4l2_subdev or video_device struct
> + * where both contains a struct media_entity.
> + * Those structures should embedded the dcmipp_ent_device struct through
> + * v4l2_set_subdevdata() and video_set_drvdata() respectivaly, allowing the
> + * dcmipp_ent_device struct to be retrieved from the corresponding struct
> + * media_entity
> + */
> +struct dcmipp_ent_device {
> + struct media_entity *ent;
> + struct media_pad *pads;
> + void * (*process_frame)(struct dcmipp_ent_device *ved,
> + const void *frame);
> + void (*vdev_get_format)(struct dcmipp_ent_device *ved,
> + struct v4l2_pix_format *fmt);
> +
> + /* Parallel input device */
> + struct v4l2_mbus_config_parallel bus;
> + enum v4l2_mbus_type bus_type;
> + irq_handler_t handler;
> + irqreturn_t handler_ret;
> + irq_handler_t thread_fn;
> +};
> +
> +/**
> + * dcmipp_pads_init - initialize pads
> + *
> + * @num_pads: number of pads to initialize
> + * @pads_flags: flags to use in each pad
> + *
> + * Helper functions to allocate/initialize pads
> + */
> +struct media_pad *dcmipp_pads_init(u16 num_pads,
> + const unsigned long *pads_flag);
> +
> +/**
> + * dcmipp_pads_cleanup - free pads
> + *
> + * @pads: pointer to the pads
> + *
> + * Helper function to free the pads initialized with dcmipp_pads_init
> + */
> +static inline void dcmipp_pads_cleanup(struct media_pad *pads)
> +{
> + kfree(pads);
> +}
> +
> +/**
> + * dcmipp_ent_sd_register - initialize and register a subdev node
> + *
> + * @ved: the dcmipp_ent_device struct to be initialize
> + * @sd: the v4l2_subdev struct to be initialize and registered
> + * @v4l2_dev: the v4l2 device to register the v4l2_subdev
> + * @name: name of the sub-device. Please notice that the name must be
> + * unique.
> + * @function: media entity function defined by MEDIA_ENT_F_* macros
> + * @num_pads: number of pads to initialize
> + * @pads_flag: flags to use in each pad
> + * @sd_int_ops: pointer to &struct v4l2_subdev_internal_ops
> + * @sd_ops: pointer to &struct v4l2_subdev_ops.
> + *
> + * Helper function initialize and register the struct dcmipp_ent_device and struct
> + * v4l2_subdev which represents a subdev node in the topology
> + */
> +int dcmipp_ent_sd_register(struct dcmipp_ent_device *ved,
> + struct v4l2_subdev *sd,
> + struct v4l2_device *v4l2_dev,
> + const char *const name,
> + u32 function,
> + u16 num_pads,
> + const unsigned long *pads_flag,
> + const struct v4l2_subdev_internal_ops *sd_int_ops,
> + const struct v4l2_subdev_ops *sd_ops,
> + irq_handler_t handler,
> + irq_handler_t thread_fn);
> +
> +/**
> + * dcmipp_ent_sd_unregister - cleanup and unregister a subdev node
> + *
> + * @ved: the dcmipp_ent_device struct to be cleaned up
> + * @sd: the v4l2_subdev struct to be unregistered
> + *
> + * Helper function cleanup and unregister the struct dcmipp_ent_device and struct
> + * v4l2_subdev which represents a subdev node in the topology
> + */
> +void dcmipp_ent_sd_unregister(struct dcmipp_ent_device *ved,
> + struct v4l2_subdev *sd);
> +
> +/**
> + * dcmipp_link_validate - validates a media link
> + *
> + * @link: pointer to &struct media_link
> + *
> + * This function call validates if a media link is valid for streaming.
> + */
> +int dcmipp_link_validate(struct media_link *link);
> +
> +#define reg_write(device, reg, val) \
> + (reg_write_dbg((device)->dev, #reg, (device)->regs, (reg), (val)))
> +#define reg_read(device, reg) \
> + (reg_read_dbg((device)->dev, #reg, (device)->regs, (reg)))
> +#define reg_set(device, reg, mask) \
> + (reg_set_dbg((device)->dev, #reg, (device)->regs, (reg), (mask)))
> +#define reg_clear(device, reg, mask) \
> + (reg_clear_dbg((device)->dev, #reg, (device)->regs, (reg), (mask)))
> +
> +static inline u32 reg_read_dbg(struct device *dev, const char *regname,
> + void __iomem *base, u32 reg)
> +{
> + u32 val = readl_relaxed(base + reg);
> +
> + dev_dbg(dev, "RD %s %#10.8x\n", regname, val);
> + return val;
> +}
> +
> +static inline void reg_write_dbg(struct device *dev, const char *regname,
> + void __iomem *base, u32 reg, u32 val)
> +{
> + dev_dbg(dev, "WR %s %#10.8x\n", regname, val);
> + writel_relaxed(val, base + reg);
> +}
> +
> +static inline void reg_set_dbg(struct device *dev, const char *regname,
> + void __iomem *base, u32 reg, u32 mask)
> +{
> + dev_dbg(dev, "SET %s %#10.8x\n", regname, mask);
> + reg_write_dbg(dev, regname, base, reg, readl_relaxed(base + reg) | mask);
> +}
> +
> +static inline void reg_clear_dbg(struct device *dev, const char *regname,
> + void __iomem *base, u32 reg, u32 mask)
> +{
> + dev_dbg(dev, "CLR %s %#10.8x\n", regname, mask);
> + reg_write_dbg(dev, regname, base, reg, readl_relaxed(base + reg) & ~mask);
> +}
> +
> +#endif
> +
> diff --git a/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-core.c b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-core.c
> new file mode 100644
> index 000000000000..aa7ae9a5b1a8
> --- /dev/null
> +++ b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-core.c
> @@ -0,0 +1,682 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for STM32 Digital Camera Memory Interface Pixel Processor
> + *
> + * Copyright (C) STMicroelectronics SA 2022
> + * Authors: Hugues Fruchet <hugues.fruchet@xxxxxxxxxxx>
> + * Alain Volmat <alain.volmat@xxxxxxxxxxx>
> + * for STMicroelectronics.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/component.h>
> +#include <linux/delay.h>
> +#include <linux/init.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/of_graph.h>

#include <linux/property.h> instead of these three.

> +#include <linux/pinctrl/consumer.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/reset.h>
> +#include <media/media-device.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-fwnode.h>
> +
> +#include "dcmipp-common.h"
> +
> +#define DCMIPP_MDEV_MODEL_NAME "DCMIPP MDEV"
> +
> +#define DCMIPP_ENT_LINK(src, srcpad, sink, sinkpad, link_flags) { \
> + .src_ent = src, \
> + .src_pad = srcpad, \
> + .sink_ent = sink, \
> + .sink_pad = sinkpad, \
> + .flags = link_flags, \
> +}
> +
> +#define DCMIPP_CMHWCFGR (0x200)
> +#define DCMIPP_P0HWCFGR (0x400)
> +#define DCMIPP_VERR (0xFF4)
> +
> +struct dcmipp_device {
> + /* The platform device */
> + struct platform_device pdev;
> + struct device *dev;
> +
> + /* Hardware resources */
> + struct reset_control *rstc;
> + void __iomem *regs;
> + struct clk *kclk;
> +
> + /* The pipeline configuration */
> + const struct dcmipp_pipeline_config *pipe_cfg;
> +
> + /* The Associated media_device parent */
> + struct media_device mdev;
> +
> + /* Internal v4l2 parent device*/
> + struct v4l2_device v4l2_dev;
> +
> + /* Subdevices */
> + struct platform_device **subdevs;
> +
> + struct v4l2_async_notifier notifier;
> +};
> +
> +static inline struct dcmipp_device *notifier_to_dcmipp(struct v4l2_async_notifier *n)
> +{
> + return container_of(n, struct dcmipp_device, notifier);
> +}
> +
> +/* Structure which describes individual configuration for each entity */
> +struct dcmipp_ent_config {
> + const char *name;
> + const char *drv;
> +};
> +
> +/* Structure which describes links between entities */
> +struct dcmipp_ent_link {
> + unsigned int src_ent;
> + u16 src_pad;
> + unsigned int sink_ent;
> + u16 sink_pad;
> + u32 flags;
> +};
> +
> +/* Structure which describes the whole topology */
> +struct dcmipp_pipeline_config {
> + const struct dcmipp_ent_config *ents;
> + size_t num_ents;
> + const struct dcmipp_ent_link *links;
> + size_t num_links;
> +};
> +
> +/* --------------------------------------------------------------------------
> + * Topology Configuration
> + */
> +
> +static const struct dcmipp_ent_config stm32mp13_ent_config[] = {
> + {
> + .name = "dcmipp_parallel",
> + .drv = "dcmipp-parallel",
> + },
> + {
> + .name = "dcmipp_dump_postproc",
> + .drv = "dcmipp-byteproc",
> + },
> + {
> + .name = "dcmipp_dump_capture",
> + .drv = "dcmipp-bytecap",
> + },
> +};
> +
> +#define ID_PARALLEL 0
> +#define ID_DUMP_BYTEPROC 1
> +#define ID_DUMP_CAPTURE 2
> +
> +static const struct dcmipp_ent_link stm32mp13_ent_links[] = {
> + DCMIPP_ENT_LINK(ID_PARALLEL, 1, ID_DUMP_BYTEPROC, 0,
> + MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE),
> + DCMIPP_ENT_LINK(ID_DUMP_BYTEPROC, 1, ID_DUMP_CAPTURE, 0,
> + MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE),
> +};
> +
> +static const struct dcmipp_pipeline_config stm32mp13_pipe_cfg = {
> + .ents = stm32mp13_ent_config,
> + .num_ents = ARRAY_SIZE(stm32mp13_ent_config),
> + .links = stm32mp13_ent_links,
> + .num_links = ARRAY_SIZE(stm32mp13_ent_links)
> +};
> +
> +/* -------------------------------------------------------------------------- */
> +#define LINK_FLAG_TO_STR(f) ((f) == 0 ? "" :\
> + (f) == MEDIA_LNK_FL_ENABLED ? "ENABLED" :\
> + (f) == MEDIA_LNK_FL_IMMUTABLE ? "IMMUTABLE" :\
> + (f) == (MEDIA_LNK_FL_ENABLED |\
> + MEDIA_LNK_FL_IMMUTABLE) ?\
> + "ENABLED, IMMUTABLE" :\
> + "UNKNOWN")
> +
> +static int dcmipp_create_links(struct dcmipp_device *dcmipp)
> +{
> + unsigned int i;
> + int ret;
> +
> + /* Initialize the links between entities */
> + for (i = 0; i < dcmipp->pipe_cfg->num_links; i++) {
> + const struct dcmipp_ent_link *link = &dcmipp->pipe_cfg->links[i];
> + /*
> + * TODO: Check another way of retrieving ved struct without
> + * relying on platform_get_drvdata
> + */
> + struct dcmipp_ent_device *ved_src =
> + platform_get_drvdata(dcmipp->subdevs[link->src_ent]);
> + struct dcmipp_ent_device *ved_sink =
> + platform_get_drvdata(dcmipp->subdevs[link->sink_ent]);
> +
> + dev_dbg(dcmipp->dev, "Create link \"%s\":%d -> %d:\"%s\" [%s]\n",
> + dcmipp->pipe_cfg->ents[link->src_ent].name,
> + link->src_pad,
> + link->sink_pad,
> + dcmipp->pipe_cfg->ents[link->sink_ent].name,
> + LINK_FLAG_TO_STR(link->flags));
> +
> + ret = media_create_pad_link(ved_src->ent, link->src_pad,
> + ved_sink->ent, link->sink_pad,
> + link->flags);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int dcmipp_graph_init(struct dcmipp_device *dcmipp);
> +
> +static int dcmipp_comp_bind(struct device *master)
> +{
> + struct dcmipp_device *dcmipp = platform_get_drvdata(to_platform_device(master));
> + struct dcmipp_bind_data bind_data;
> + int ret;
> +
> + /* Register the v4l2 struct */
> + ret = v4l2_device_register(dcmipp->mdev.dev, &dcmipp->v4l2_dev);
> + if (ret) {
> + dev_err(dcmipp->mdev.dev,
> + "v4l2 device register failed (err=%d)\n", ret);
> + return ret;
> + }
> +
> + /* Bind subdevices */
> + bind_data.v4l2_dev = &dcmipp->v4l2_dev;
> + bind_data.rstc = dcmipp->rstc;
> + bind_data.regs = dcmipp->regs;
> + ret = component_bind_all(master, &bind_data);
> + if (ret)
> + goto err_v4l2_unregister;
> +
> + /* Initialize links */
> + ret = dcmipp_create_links(dcmipp);
> + if (ret)
> + goto err_comp_unbind_all;
> +
> + ret = dcmipp_graph_init(dcmipp);
> + if (ret < 0)
> + return ret;
> +
> + return 0;
> +
> + media_device_unregister(&dcmipp->mdev);
> + media_device_cleanup(&dcmipp->mdev);
> +err_comp_unbind_all:
> + component_unbind_all(master, NULL);
> +err_v4l2_unregister:
> + v4l2_device_unregister(&dcmipp->v4l2_dev);
> +
> + return ret;
> +}
> +
> +static void dcmipp_comp_unbind(struct device *master)
> +{
> + struct dcmipp_device *dcmipp = platform_get_drvdata(to_platform_device(master));
> +
> + v4l2_async_nf_unregister(&dcmipp->notifier);
> + v4l2_async_nf_cleanup(&dcmipp->notifier);
> +
> + media_device_unregister(&dcmipp->mdev);
> + media_device_cleanup(&dcmipp->mdev);
> + component_unbind_all(master, NULL);
> + v4l2_device_unregister(&dcmipp->v4l2_dev);
> +}
> +
> +static int dcmipp_comp_compare(struct device *comp, void *data)
> +{
> + return comp == data;
> +}
> +
> +static struct component_match *dcmipp_add_subdevs(struct dcmipp_device *dcmipp)
> +{
> + struct component_match *match = NULL;
> + struct dcmipp_platform_data pdata;
> + int i;
> +
> + for (i = 0; i < dcmipp->pipe_cfg->num_ents; i++) {
> + dev_dbg(dcmipp->dev, "new pdev for %s (%s)\n",
> + dcmipp->pipe_cfg->ents[i].drv,
> + dcmipp->pipe_cfg->ents[i].name);
> +
> + strscpy(pdata.entity_name, dcmipp->pipe_cfg->ents[i].name,
> + sizeof(pdata.entity_name));
> +
> + dcmipp->subdevs[i] =
> + platform_device_register_data
> + (dcmipp->dev,
> + dcmipp->pipe_cfg->ents[i].drv,
> + PLATFORM_DEVID_AUTO,
> + &pdata,
> + sizeof(pdata));
> + if (IS_ERR(dcmipp->subdevs[i])) {
> + match = ERR_CAST(dcmipp->subdevs[i]);
> + while (--i >= 0)
> + platform_device_unregister(dcmipp->subdevs[i]);
> +
> + dev_err(dcmipp->mdev.dev,
> + "%s error (err=%ld)\n", __func__,
> + PTR_ERR(match));
> + return match;
> + }
> +
> + component_match_add(dcmipp->dev, &match, dcmipp_comp_compare,
> + &dcmipp->subdevs[i]->dev);
> + }
> +
> + return match;
> +}
> +
> +static void dcmipp_rm_subdevs(struct dcmipp_device *dcmipp)
> +{
> + unsigned int i;
> +
> + for (i = 0; i < dcmipp->pipe_cfg->num_ents; i++)
> + platform_device_unregister(dcmipp->subdevs[i]);
> +}
> +
> +static const struct component_master_ops dcmipp_comp_ops = {
> + .bind = dcmipp_comp_bind,
> + .unbind = dcmipp_comp_unbind,
> +};
> +
> +static const struct of_device_id dcmipp_of_match[] = {
> + { .compatible = "st,stm32mp13-dcmipp", .data = &stm32mp13_pipe_cfg},

Space before '}'.

> + { /* end node */ },
> +};
> +MODULE_DEVICE_TABLE(of, dcmipp_of_match);
> +
> +static int dcmipp_graph_notify_complete(struct v4l2_async_notifier *notifier)
> +{
> + struct dcmipp_device *dcmipp = notifier_to_dcmipp(notifier);
> + int ret;
> +
> + /* Register the media device */
> + ret = media_device_register(&dcmipp->mdev);
> + if (ret) {
> + dev_err(dcmipp->mdev.dev,
> + "media device register failed (err=%d)\n", ret);
> + return ret;
> + }
> +
> + /* Expose all subdev's nodes*/
> + ret = v4l2_device_register_subdev_nodes(&dcmipp->v4l2_dev);
> + if (ret) {
> + dev_err(dcmipp->mdev.dev,
> + "dcmipp subdev nodes registration failed (err=%d)\n",
> + ret);
> + media_device_unregister(&dcmipp->mdev);
> + return ret;
> + }
> +
> + dev_dbg(dcmipp->dev, "Notify complete !\n");
> +
> + return 0;
> +}
> +
> +static void dcmipp_graph_notify_unbind(struct v4l2_async_notifier *notifier,
> + struct v4l2_subdev *sd,
> + struct v4l2_async_subdev *asd)
> +{
> + struct dcmipp_device *dcmipp = notifier_to_dcmipp(notifier);
> +
> + dev_dbg(dcmipp->dev, "Removing %s\n", sd->name);
> +}
> +
> +static irqreturn_t dcmipp_irq_thread(int irq, void *arg)
> +{
> + struct dcmipp_device *dcmipp = arg;
> + struct dcmipp_ent_device *ved;
> + unsigned int i;
> +
> + /* Call irq thread of each entities of pipeline */
> + for (i = 0; i < dcmipp->pipe_cfg->num_ents; i++) {
> + ved = platform_get_drvdata(dcmipp->subdevs[i]);
> + if (ved->thread_fn && ved->handler_ret == IRQ_WAKE_THREAD)
> + ved->thread_fn(irq, ved);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t dcmipp_irq_callback(int irq, void *arg)
> +{
> + struct dcmipp_device *dcmipp = arg;
> + struct dcmipp_ent_device *ved;
> + irqreturn_t ret = IRQ_HANDLED;
> + unsigned int i;
> +
> + /* Call irq handler of each entities of pipeline */
> + for (i = 0; i < dcmipp->pipe_cfg->num_ents; i++) {
> + ved = platform_get_drvdata(dcmipp->subdevs[i]);
> + if (ved->handler)
> + ved->handler_ret = ved->handler(irq, ved);
> + else if (ved->thread_fn)
> + ved->handler_ret = IRQ_WAKE_THREAD;
> + else
> + ved->handler_ret = IRQ_HANDLED;

Does this need to be serialised somehow (access to ved->handler_ret, that
is)?

> + if (ved->handler_ret != IRQ_HANDLED)
> + ret = ved->handler_ret;
> + }
> +
> + return ret;
> +}
> +
> +static int dcmipp_graph_notify_bound(struct v4l2_async_notifier *notifier,
> + struct v4l2_subdev *subdev,
> + struct v4l2_async_subdev *asd)
> +{
> + struct dcmipp_device *dcmipp = notifier_to_dcmipp(notifier);
> + unsigned int ret;
> + int src_pad;
> + struct dcmipp_ent_device *sink;
> + struct device_node *np = dcmipp->dev->of_node;
> + struct v4l2_fwnode_endpoint ep = { .bus_type = 0 };

Please set bus_type explicitly (DPHY)?

> +
> + dev_dbg(dcmipp->dev, "Subdev \"%s\" bound\n", subdev->name);
> +
> + /*
> + * Link this sub-device to DCMIPP, it could be
> + * a parallel camera sensor or a CSI-2 to parallel bridge
> + */
> +

No need for a newline.

> + src_pad = media_entity_get_fwnode_pad(&subdev->entity,
> + subdev->fwnode,
> + MEDIA_PAD_FL_SOURCE);
> +
> + /* Get bus characteristics from devicetree */
> + np = of_graph_get_next_endpoint(np, NULL);
> + if (!np) {
> + dev_err(dcmipp->dev, "Could not find the endpoint\n");
> + of_node_put(np);
> + return -ENODEV;
> + }
> +
> + ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(np), &ep);
> + of_node_put(np);
> + if (ret) {
> + dev_err(dcmipp->dev, "Could not parse the endpoint\n");
> + return ret;
> + }
> +
> + if ((ep.bus_type == V4L2_MBUS_PARALLEL ||
> + ep.bus_type == V4L2_MBUS_BT656) &&
> + ep.bus.parallel.bus_width > 0) {
> + /* Only 8 bits bus width supported with BT656 bus */
> + if (ep.bus_type == V4L2_MBUS_BT656 &&
> + ep.bus.parallel.bus_width != 8) {
> + dev_err(dcmipp->dev, "BT656 bus conflicts with %u bits bus width (8 bits required)\n",
> + ep.bus.parallel.bus_width);
> + return -ENODEV;
> + }
> +
> + /*
> + * Parallel input device detected
> + * Connect it to parallel subdev
> + */
> + sink = platform_get_drvdata(dcmipp->subdevs[ID_PARALLEL]);
> + sink->bus.flags = ep.bus.parallel.flags;
> + sink->bus.bus_width = ep.bus.parallel.bus_width;
> + sink->bus.data_shift = ep.bus.parallel.data_shift;
> + sink->bus_type = ep.bus_type;
> + ret = media_create_pad_link(&subdev->entity, src_pad,
> + sink->ent, 0,
> + MEDIA_LNK_FL_IMMUTABLE |
> + MEDIA_LNK_FL_ENABLED);
> + if (ret)
> + dev_err(dcmipp->dev, "Failed to create media pad link with subdev \"%s\"\n",
> + subdev->name);
> + else
> + dev_dbg(dcmipp->dev, "DCMIPP is now linked to \"%s\"\n",
> + subdev->name);
> +
> + return 0;
> + }
> +
> + return ret;
> +}
> +
> +static const struct v4l2_async_notifier_operations dcmipp_graph_notify_ops = {
> + .bound = dcmipp_graph_notify_bound,
> + .unbind = dcmipp_graph_notify_unbind,
> + .complete = dcmipp_graph_notify_complete,
> +};
> +
> +static int dcmipp_graph_init(struct dcmipp_device *dcmipp)
> +{
> + struct v4l2_async_subdev *asd;
> + struct device_node *ep;
> + int ret;
> +
> + ep = of_graph_get_next_endpoint(dcmipp->dev->of_node, NULL);

You could switch to device property API:

struct fwnode_handle *ep;

ep = fwnode_graph_get_next_endpoint(dev_fwnode(dcmipp->dev), NULL);

> + if (!ep) {
> + dev_err(dcmipp->dev, "Failed to get next endpoint\n");
> + return -EINVAL;
> + }
> +
> + v4l2_async_nf_init(&dcmipp->notifier);

V4L2 async API has just changed slightly: you'd call
v4l2_async_nf_init(&dcmipp->notifier, &dcmipp->v4l2_dev) here. The notifier
registration just takes the notifier.

Be sure to register the v4l2_device first (probably already done but I
didn't check).

> +
> + asd = v4l2_async_nf_add_fwnode_remote

Don't wrap just before or after '('.

> + (&dcmipp->notifier, of_fwnode_handle(ep),
> + struct v4l2_async_subdev);

struct v4l2_async_subdev is now struct v4l2_async_connection.

> +
> + of_node_put(ep);

fwnode_handle_put(ep);

> +
> + if (IS_ERR(asd)) {
> + dev_err(dcmipp->dev, "Failed to add fwnode remote subdev\n");
> + return PTR_ERR(asd);
> + }
> +
> + dcmipp->notifier.ops = &dcmipp_graph_notify_ops;
> +
> + ret = v4l2_async_nf_register(&dcmipp->v4l2_dev, &dcmipp->notifier);
> + if (ret < 0) {
> + dev_err(dcmipp->dev, "Failed to register notifier\n");
> + v4l2_async_nf_cleanup(&dcmipp->notifier);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int dcmipp_probe(struct platform_device *pdev)
> +{
> + struct dcmipp_device *dcmipp;
> + struct component_match *comp_match = NULL;
> + struct resource *res;
> + struct clk *kclk;
> + const struct dcmipp_pipeline_config *pipe_cfg;
> + int irq;
> + int ret;
> +
> + dcmipp = devm_kzalloc(&pdev->dev, sizeof(struct dcmipp_device), GFP_KERNEL);

..., sizeof(*dcmipp), ...

> + if (!dcmipp)
> + return -ENOMEM;
> +
> + dcmipp->dev = &pdev->dev;
> +
> + pipe_cfg = of_device_get_match_data(&pdev->dev);
> + if (!pipe_cfg) {
> + dev_err(&pdev->dev, "Can't get device data\n");
> + return -ENODEV;
> + }
> + dcmipp->pipe_cfg = pipe_cfg;
> +
> + platform_set_drvdata(pdev, dcmipp);
> +
> + /* Get hardware resources from devicetree */
> + dcmipp->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
> + if (IS_ERR(dcmipp->rstc))
> + return dev_err_probe(&pdev->dev, PTR_ERR(dcmipp->rstc),
> + "Could not get reset control\n");
> +
> + irq = platform_get_irq(pdev, 0);
> + if (irq <= 0) {
> + if (irq != -EPROBE_DEFER)
> + dev_err(&pdev->dev, "Could not get irq\n");
> + return irq ? irq : -ENXIO;
> + }
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (!res) {
> + dev_err(&pdev->dev, "Could not get resource\n");
> + return -ENODEV;
> + }
> +
> + dcmipp->regs = devm_ioremap_resource(&pdev->dev, res);

devm_platform_get_and_ioremap_resource()?

> + if (IS_ERR(dcmipp->regs)) {
> + dev_err(&pdev->dev, "Could not map registers\n");
> + return PTR_ERR(dcmipp->regs);
> + }
> +
> + ret = devm_request_threaded_irq(&pdev->dev, irq, dcmipp_irq_callback,
> + dcmipp_irq_thread, IRQF_ONESHOT,
> + dev_name(&pdev->dev), dcmipp);
> + if (ret) {
> + dev_err(&pdev->dev, "Unable to request irq %d\n", irq);
> + return ret;
> + }
> +
> + /* Reset device */
> + ret = reset_control_assert(dcmipp->rstc);
> + if (ret) {
> + dev_err(&pdev->dev, "Failed to assert the reset line\n");
> + return ret;
> + }
> +
> + usleep_range(3000, 5000);
> +
> + ret = reset_control_deassert(dcmipp->rstc);
> + if (ret) {
> + dev_err(&pdev->dev, "Failed to deassert the reset line\n");
> + return ret;
> + }
> +
> + kclk = devm_clk_get(&pdev->dev, "kclk");
> + if (IS_ERR(kclk))
> + return dev_err_probe(&pdev->dev, PTR_ERR(kclk),
> + "Unable to get kclk\n");
> + dcmipp->kclk = kclk;
> +
> + /* Create platform_device for each entity in the topology */
> + dcmipp->subdevs = devm_kcalloc(&pdev->dev, dcmipp->pipe_cfg->num_ents,
> + sizeof(*dcmipp->subdevs), GFP_KERNEL);
> + if (!dcmipp->subdevs)
> + return -ENOMEM;
> +
> + comp_match = dcmipp_add_subdevs(dcmipp);
> + if (IS_ERR(comp_match))
> + return PTR_ERR(comp_match);
> +
> + /* Link the media device within the v4l2_device */
> + dcmipp->v4l2_dev.mdev = &dcmipp->mdev;
> +
> + /* Initialize media device */
> + strscpy(dcmipp->mdev.model, DCMIPP_MDEV_MODEL_NAME,
> + sizeof(dcmipp->mdev.model));
> + snprintf(dcmipp->mdev.bus_info, sizeof(dcmipp->mdev.bus_info),
> + "platform:%s", DCMIPP_PDEV_NAME);

bus_info is set by media_device_init() nowadays.

> + dcmipp->mdev.dev = &pdev->dev;
> + media_device_init(&dcmipp->mdev);
> +
> + /* Add self to the component system */
> + ret = component_master_add_with_match(&pdev->dev, &dcmipp_comp_ops,
> + comp_match);
> + if (ret) {
> + media_device_cleanup(&dcmipp->mdev);
> + dcmipp_rm_subdevs(dcmipp);
> + return ret;
> + }
> +
> + pm_runtime_enable(dcmipp->dev);
> +
> + dev_info(&pdev->dev, "Probe done");
> +
> + return 0;
> +}
> +
> +static int dcmipp_remove(struct platform_device *pdev)
> +{
> + struct dcmipp_device *dcmipp = platform_get_drvdata(pdev);
> +
> + pm_runtime_disable(&pdev->dev);
> +
> + component_master_del(&pdev->dev, &dcmipp_comp_ops);
> + dcmipp_rm_subdevs(dcmipp);
> +
> + return 0;
> +}
> +
> +static __maybe_unused int dcmipp_runtime_suspend(struct device *dev)
> +{
> + struct dcmipp_device *dcmipp = dev_get_drvdata(dev);
> +
> + clk_disable_unprepare(dcmipp->kclk);
> +
> + return 0;
> +}
> +
> +static __maybe_unused int dcmipp_runtime_resume(struct device *dev)
> +{
> + struct dcmipp_device *dcmipp = dev_get_drvdata(dev);
> + int ret;
> +
> + ret = clk_prepare_enable(dcmipp->kclk);
> + if (ret)
> + dev_err(dev, "%s: Failed to prepare_enable k clock\n", __func__);
> +
> + return ret;
> +}
> +
> +static __maybe_unused int dcmipp_suspend(struct device *dev)
> +{
> + /* disable clock */
> + pm_runtime_force_suspend(dev);
> +
> + /* change pinctrl state */
> + pinctrl_pm_select_sleep_state(dev);
> +
> + return 0;
> +}
> +
> +static __maybe_unused int dcmipp_resume(struct device *dev)
> +{
> + /* restore pinctl default state */
> + pinctrl_pm_select_default_state(dev);
> +
> + /* clock enable */
> + pm_runtime_force_resume(dev);
> +
> + return 0;
> +}
> +
> +static const struct dev_pm_ops dcmipp_pm_ops = {
> + SET_SYSTEM_SLEEP_PM_OPS(dcmipp_suspend, dcmipp_resume)
> + SET_RUNTIME_PM_OPS(dcmipp_runtime_suspend,
> + dcmipp_runtime_resume, NULL)
> +};
> +
> +static struct platform_driver dcmipp_pdrv = {
> + .probe = dcmipp_probe,
> + .remove = dcmipp_remove,
> + .driver = {
> + .name = DCMIPP_PDEV_NAME,
> + .of_match_table = of_match_ptr(dcmipp_of_match),

Please don't use of_match_ptr().

> + .pm = &dcmipp_pm_ops,
> + },
> +};
> +
> +module_platform_driver(dcmipp_pdrv);
> +
> +MODULE_AUTHOR("Hugues Fruchet <hugues.fruchet@xxxxxxxxxxx>");
> +MODULE_AUTHOR("Alain Volmat <alain.volmat@xxxxxxxxxxx>");
> +MODULE_DESCRIPTION("STMicroelectronics STM32 Digital Camera Memory Interface with Pixel Processor driver");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-parallel.c b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-parallel.c
> new file mode 100644
> index 000000000000..37215791c01c
> --- /dev/null
> +++ b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-parallel.c
> @@ -0,0 +1,497 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for STM32 Digital Camera Memory Interface Pixel Processor
> + *
> + * Copyright (C) STMicroelectronics SA 2022
> + * Authors: Hugues Fruchet <hugues.fruchet@xxxxxxxxxxx>
> + * Alain Volmat <alain.volmat@xxxxxxxxxxx>
> + * for STMicroelectronics.
> + */
> +
> +#include <linux/component.h>
> +#include <linux/module.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/platform_device.h>
> +#include <linux/v4l2-mediabus.h>
> +#include <linux/vmalloc.h>
> +#include <media/v4l2-event.h>
> +#include <media/v4l2-subdev.h>
> +
> +#include "dcmipp-common.h"
> +
> +#define DCMIPP_PAR_DRV_NAME "dcmipp-parallel"
> +
> +#define DCMIPP_PRCR (0x104)
> +#define DCMIPP_PRCR_FORMAT_SHIFT 16
> +#define DCMIPP_PRCR_FORMAT_YUV422 0x1E
> +#define DCMIPP_PRCR_FORMAT_RGB565 0x22
> +#define DCMIPP_PRCR_FORMAT_RAW8 0x2A
> +#define DCMIPP_PRCR_FORMAT_G8 0x4A
> +#define DCMIPP_PRCR_FORMAT_BYTE_STREAM 0x5A
> +#define DCMIPP_PRCR_ESS BIT(4)
> +#define DCMIPP_PRCR_PCKPOL BIT(5)
> +#define DCMIPP_PRCR_HSPOL BIT(6)
> +#define DCMIPP_PRCR_VSPOL BIT(7)
> +#define DCMIPP_PRCR_ENABLE BIT(14)
> +#define DCMIPP_PRCR_SWAPCYCLES BIT(25)
> +#define DCMIPP_PRCR_SWAPBITS BIT(26)
> +
> +#define DCMIPP_PRESCR (0x108)
> +#define DCMIPP_PRESUR (0x10c)
> +
> +#define IS_SINK(pad) (!(pad))
> +#define IS_SRC(pad) ((pad))
> +
> +#define PAR_MEDIA_BUS_FMT_DEFAULT MEDIA_BUS_FMT_RGB565_2X8_LE
> +
> +struct dcmipp_par_pix_map {
> + unsigned int code_sink;
> + unsigned int code_src;
> + u8 prcr_format;
> + u8 prcr_swapbits;
> + u8 prcr_swapcycles;
> +};
> +
> +#define PIXMAP_SINK_SRC_PRCR_SWAP(sink, src, prcr, swap) \
> + { \
> + .code_sink = MEDIA_BUS_FMT_##sink, \
> + .code_src = MEDIA_BUS_FMT_##src, \
> + .prcr_format = DCMIPP_PRCR_FORMAT_##prcr, \
> + .prcr_swapcycles = swap, \
> + }
> +static const struct dcmipp_par_pix_map dcmipp_par_pix_map_list[] = {
> + /* RGB565 */
> + PIXMAP_SINK_SRC_PRCR_SWAP(RGB565_2X8_LE, RGB565_2X8_LE, RGB565, 1),
> + PIXMAP_SINK_SRC_PRCR_SWAP(RGB565_2X8_BE, RGB565_2X8_LE, RGB565, 0),
> + /* YUV422 */
> + PIXMAP_SINK_SRC_PRCR_SWAP(YUYV8_2X8, YUYV8_2X8, YUV422, 1),
> + PIXMAP_SINK_SRC_PRCR_SWAP(YUYV8_2X8, UYVY8_2X8, YUV422, 0),
> + PIXMAP_SINK_SRC_PRCR_SWAP(UYVY8_2X8, UYVY8_2X8, YUV422, 1),
> + PIXMAP_SINK_SRC_PRCR_SWAP(UYVY8_2X8, YUYV8_2X8, YUV422, 0),
> + PIXMAP_SINK_SRC_PRCR_SWAP(YVYU8_2X8, YVYU8_2X8, YUV422, 1),
> + PIXMAP_SINK_SRC_PRCR_SWAP(VYUY8_2X8, VYUY8_2X8, YUV422, 1),
> + /* GREY */
> + PIXMAP_SINK_SRC_PRCR_SWAP(Y8_1X8, Y8_1X8, G8, 0),
> + /* Raw Bayer */
> + PIXMAP_SINK_SRC_PRCR_SWAP(SBGGR8_1X8, SBGGR8_1X8, RAW8, 0),
> + PIXMAP_SINK_SRC_PRCR_SWAP(SGBRG8_1X8, SGBRG8_1X8, RAW8, 0),
> + PIXMAP_SINK_SRC_PRCR_SWAP(SGRBG8_1X8, SGRBG8_1X8, RAW8, 0),
> + PIXMAP_SINK_SRC_PRCR_SWAP(SRGGB8_1X8, SRGGB8_1X8, RAW8, 0),
> + /* JPEG */
> + PIXMAP_SINK_SRC_PRCR_SWAP(JPEG_1X8, JPEG_1X8, BYTE_STREAM, 0),
> +};
> +
> +/*
> + * Search through the pix_map table, skipping two consecutive entry with the
> + * same code
> + */
> +static inline const struct dcmipp_par_pix_map *dcmipp_par_pix_map_by_index
> + (unsigned int index,
> + unsigned int pad)
> +{
> + const struct dcmipp_par_pix_map *l = dcmipp_par_pix_map_list;
> + unsigned int size = ARRAY_SIZE(dcmipp_par_pix_map_list);
> + unsigned int i = 0;
> + u32 prev_code = 0, cur_code;
> +
> + while (i < size) {
> + if (IS_SRC(pad))
> + cur_code = l[i].code_src;
> + else
> + cur_code = l[i].code_sink;
> +
> + if (cur_code == prev_code) {
> + i++;
> + continue;
> + } else {

Else is useless.

> + prev_code = cur_code;
> + }
> +
> + if (index == 0)
> + break;
> + i++;
> + index--;
> + }
> +
> + if (i >= size)
> + return NULL;
> +
> + return &l[i];
> +}
> +
> +static inline const struct dcmipp_par_pix_map *dcmipp_par_pix_map_by_code
> + (u32 code_sink, u32 code_src)
> +{
> + const struct dcmipp_par_pix_map *l = dcmipp_par_pix_map_list;
> + unsigned int size = ARRAY_SIZE(dcmipp_par_pix_map_list);
> + unsigned int i;
> +
> + for (i = 0; i < size; i++) {
> + if ((l[i].code_sink == code_sink && l[i].code_src == code_src) ||
> + (l[i].code_sink == code_src && l[i].code_src == code_sink) ||
> + (l[i].code_sink == code_sink && code_src == 0) ||
> + (code_sink == 0 && l[i].code_src == code_src))
> + return &l[i];
> + }
> + return NULL;
> +}
> +
> +struct dcmipp_par_device {
> + struct dcmipp_ent_device ved;
> + struct v4l2_subdev sd;
> + struct device *dev;
> + /* The active format */
> + struct v4l2_mbus_framefmt sink_format;
> + struct v4l2_mbus_framefmt src_format;
> + bool streaming;
> + void __iomem *regs;
> +};
> +
> +static const struct v4l2_mbus_framefmt fmt_default = {
> + .width = DCMIPP_FMT_WIDTH_DEFAULT,
> + .height = DCMIPP_FMT_HEIGHT_DEFAULT,
> + .code = PAR_MEDIA_BUS_FMT_DEFAULT,
> + .field = V4L2_FIELD_NONE,
> + .colorspace = DCMIPP_COLORSPACE_DEFAULT,
> + .ycbcr_enc = DCMIPP_YCBCR_ENC_DEFAULT,
> + .quantization = DCMIPP_QUANTIZATION_DEFAULT,
> + .xfer_func = DCMIPP_XFER_FUNC_DEFAULT,
> +};
> +
> +static int dcmipp_par_init_cfg(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state)
> +{
> + unsigned int i;
> +
> + for (i = 0; i < sd->entity.num_pads; i++) {
> + struct v4l2_mbus_framefmt *mf;
> +
> + mf = v4l2_subdev_get_try_format(sd, sd_state, i);
> + *mf = fmt_default;
> + }
> +
> + return 0;
> +}
> +
> +static int dcmipp_par_enum_mbus_code(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state,
> + struct v4l2_subdev_mbus_code_enum *code)
> +{
> + const struct dcmipp_par_pix_map *vpix =
> + dcmipp_par_pix_map_by_index(code->index, code->pad);
> +
> + if (!vpix)
> + return -EINVAL;
> +
> + code->code = IS_SRC(code->pad) ? vpix->code_src : vpix->code_sink;
> +
> + return 0;
> +}
> +
> +static int dcmipp_par_enum_frame_size(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state,
> + struct v4l2_subdev_frame_size_enum *fse)
> +{
> + const struct dcmipp_par_pix_map *vpix;
> +
> + if (fse->index)
> + return -EINVAL;
> +
> + /* Only accept code in the pix map table */
> + vpix = dcmipp_par_pix_map_by_code(IS_SINK(fse->pad) ? fse->code : 0,
> + IS_SRC(fse->pad) ? fse->code : 0);
> + if (!vpix)
> + return -EINVAL;
> +
> + fse->min_width = DCMIPP_FRAME_MIN_WIDTH;
> + fse->max_width = DCMIPP_FRAME_MAX_WIDTH;
> + fse->min_height = DCMIPP_FRAME_MIN_HEIGHT;
> + fse->max_height = DCMIPP_FRAME_MAX_HEIGHT;
> +
> + return 0;
> +}
> +
> +static int dcmipp_par_get_fmt(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state,
> + struct v4l2_subdev_format *fmt)
> +{
> + struct dcmipp_par_device *par =
> + container_of(sd, struct dcmipp_par_device, sd);
> +
> + fmt->format = fmt->which == V4L2_SUBDEV_FORMAT_TRY ?
> + *v4l2_subdev_get_try_format(sd, sd_state, fmt->pad) :
> + (IS_SRC(fmt->pad) ? par->src_format : par->sink_format);
> +
> + return 0;
> +}
> +
> +static void dcmipp_par_adjust_fmt(struct dcmipp_par_device *par,
> + struct v4l2_mbus_framefmt *fmt, __u32 pad)
> +{
> + const struct dcmipp_par_pix_map *vpix;
> +
> + /* Only accept code in the pix map table */
> + vpix = dcmipp_par_pix_map_by_code(IS_SINK(pad) ? fmt->code : 0,
> + IS_SRC(pad) ? fmt->code : 0);
> + if (!vpix)
> + fmt->code = fmt_default.code;
> +
> + /* Exclude JPEG if BT656 bus is selected */
> + if (vpix && vpix->code_sink == MEDIA_BUS_FMT_JPEG_1X8 &&
> + par->ved.bus_type == V4L2_MBUS_BT656)
> + fmt->code = fmt_default.code;
> +
> + fmt->width = clamp_t(u32, fmt->width, DCMIPP_FRAME_MIN_WIDTH,
> + DCMIPP_FRAME_MAX_WIDTH) & ~1;
> + fmt->height = clamp_t(u32, fmt->height, DCMIPP_FRAME_MIN_HEIGHT,
> + DCMIPP_FRAME_MAX_HEIGHT) & ~1;
> +
> + if (fmt->field == V4L2_FIELD_ANY || fmt->field == V4L2_FIELD_ALTERNATE)
> + fmt->field = fmt_default.field;
> +
> + dcmipp_colorimetry_clamp(fmt);
> +}
> +
> +static int dcmipp_par_set_fmt(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *sd_state,
> + struct v4l2_subdev_format *fmt)
> +{
> + struct dcmipp_par_device *par = v4l2_get_subdevdata(sd);
> + struct v4l2_mbus_framefmt *mf;
> +
> + if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
> + /* Do not change the format while stream is on */
> + if (par->streaming)
> + return -EBUSY;
> +
> + mf = IS_SRC(fmt->pad) ? &par->src_format : &par->sink_format;
> + } else {
> + mf = v4l2_subdev_get_try_format(sd, sd_state, fmt->pad);
> + }
> +
> + /* Set the new format */
> + dcmipp_par_adjust_fmt(par, &fmt->format, fmt->pad);
> +
> + dev_dbg(par->dev, "%s: format update: old:%dx%d (0x%x, %d, %d, %d, %d) new:%dx%d (0x%x, %d, %d, %d, %d)\n",
> + par->sd.name,
> + /* old */
> + mf->width, mf->height, mf->code,
> + mf->colorspace, mf->quantization,
> + mf->xfer_func, mf->ycbcr_enc,
> + /* new */
> + fmt->format.width, fmt->format.height, fmt->format.code,
> + fmt->format.colorspace, fmt->format.quantization,
> + fmt->format.xfer_func, fmt->format.ycbcr_enc);
> +
> + *mf = fmt->format;
> +
> + /* When setting the sink format, report that format on the src pad as well */
> + if (IS_SINK(fmt->pad))
> + par->src_format = fmt->format;
> +
> + return 0;
> +}
> +
> +static const struct v4l2_subdev_pad_ops dcmipp_par_pad_ops = {
> + .init_cfg = dcmipp_par_init_cfg,
> + .enum_mbus_code = dcmipp_par_enum_mbus_code,
> + .enum_frame_size = dcmipp_par_enum_frame_size,
> + .get_fmt = dcmipp_par_get_fmt,
> + .set_fmt = dcmipp_par_set_fmt,
> +};
> +
> +static int dcmipp_par_configure(struct dcmipp_par_device *par)
> +{
> + u32 val = 0;
> + const struct dcmipp_par_pix_map *vpix;
> +
> + /* Set vertical synchronization polarity */
> + if (par->ved.bus.flags & V4L2_MBUS_VSYNC_ACTIVE_HIGH)
> + val |= DCMIPP_PRCR_VSPOL;
> +
> + /* Set horizontal synchronization polarity */
> + if (par->ved.bus.flags & V4L2_MBUS_HSYNC_ACTIVE_HIGH)
> + val |= DCMIPP_PRCR_HSPOL;
> +
> + /* Set pixel clock polarity */
> + if (par->ved.bus.flags & V4L2_MBUS_PCLK_SAMPLE_RISING)
> + val |= DCMIPP_PRCR_PCKPOL;
> +
> + /*
> + * BT656 embedded synchronisation bus mode.
> + *
> + * Default SAV/EAV mode is supported here with default codes
> + * SAV=0xff000080 & EAV=0xff00009d.
> + * With DCMIPP this means LSC=SAV=0x80 & LEC=EAV=0x9d.
> + */
> + if (par->ved.bus_type == V4L2_MBUS_BT656) {
> + val |= DCMIPP_PRCR_ESS;
> +
> + /* Unmask all codes */
> + reg_write(par, DCMIPP_PRESUR, 0xffffffff);/* FEC:LEC:LSC:FSC */
> +
> + /* Trig on LSC=0x80 & LEC=0x9d codes, ignore FSC and FEC */
> + reg_write(par, DCMIPP_PRESCR, 0xff9d80ff);/* FEC:LEC:LSC:FSC */
> + }
> +
> + /* Set format */
> + vpix = dcmipp_par_pix_map_by_code(par->sink_format.code,
> + par->src_format.code);
> + if (!vpix) {
> + dev_err(par->dev, "Invalid sink/src format configuration\n");
> + return -EINVAL;
> + }
> +
> + val |= vpix->prcr_format << DCMIPP_PRCR_FORMAT_SHIFT;
> +
> + /* swap LSB vs MSB within one cycle */
> + if (vpix->prcr_swapbits)
> + val |= DCMIPP_PRCR_SWAPBITS;
> +
> + /* swap cycles */
> + if (vpix->prcr_swapcycles)
> + val |= DCMIPP_PRCR_SWAPCYCLES;
> +
> + reg_write(par, DCMIPP_PRCR, val);
> +
> + return 0;
> +}
> +
> +static int dcmipp_par_s_stream(struct v4l2_subdev *sd, int enable)
> +{
> + struct dcmipp_par_device *par =
> + container_of(sd, struct dcmipp_par_device, sd);
> + int ret = 0;
> +
> + if (enable) {
> + ret = dcmipp_par_configure(par);
> + if (ret)
> + return ret;
> +
> + /* Enable parallel interface */
> + reg_set(par, DCMIPP_PRCR, DCMIPP_PRCR_ENABLE);
> + } else {
> + /* Disable parallel interface */
> + reg_clear(par, DCMIPP_PRCR, DCMIPP_PRCR_ENABLE);
> + }
> +
> + par->streaming = enable;
> + return ret;
> +}
> +
> +static const struct v4l2_subdev_video_ops dcmipp_par_video_ops = {
> + .s_stream = dcmipp_par_s_stream,
> +};
> +
> +static const struct v4l2_subdev_ops dcmipp_par_ops = {
> + .pad = &dcmipp_par_pad_ops,
> + .video = &dcmipp_par_video_ops,
> +};
> +
> +static void dcmipp_par_release(struct v4l2_subdev *sd)
> +{
> + struct dcmipp_par_device *par =
> + container_of(sd, struct dcmipp_par_device, sd);
> +
> + kfree(par);
> +}
> +
> +static const struct v4l2_subdev_internal_ops dcmipp_par_int_ops = {
> + .release = dcmipp_par_release,
> +};
> +
> +static void dcmipp_par_comp_unbind(struct device *comp, struct device *master,
> + void *master_data)
> +{
> + struct dcmipp_ent_device *ved = dev_get_drvdata(comp);
> + struct dcmipp_par_device *par =
> + container_of(ved, struct dcmipp_par_device, ved);
> +
> + dcmipp_ent_sd_unregister(ved, &par->sd);
> +}
> +
> +static int dcmipp_par_comp_bind(struct device *comp, struct device *master,
> + void *master_data)
> +{
> + struct dcmipp_bind_data *bind_data = master_data;
> + struct dcmipp_platform_data *pdata = comp->platform_data;
> + struct dcmipp_par_device *par;
> + int ret;
> +
> + /* Allocate the par struct */
> + par = kzalloc(sizeof(*par), GFP_KERNEL);
> + if (!par)
> + return -ENOMEM;
> +
> + par->regs = bind_data->regs;
> +
> + /* Initialize ved and sd */
> + ret = dcmipp_ent_sd_register
> + (&par->ved, &par->sd, bind_data->v4l2_dev,
> + pdata->entity_name,
> + MEDIA_ENT_F_VID_IF_BRIDGE, 2,
> + (const unsigned long[2]) {
> + MEDIA_PAD_FL_SINK,
> + MEDIA_PAD_FL_SOURCE,
> + },
> + &dcmipp_par_int_ops, &dcmipp_par_ops,
> + NULL, NULL);
> + if (ret)
> + goto err_free_hdl;
> +
> + dev_set_drvdata(comp, &par->ved);
> + par->dev = comp;
> +
> + /* Initialize the frame format */
> + par->sink_format = fmt_default;
> + par->src_format = fmt_default;
> +
> + return 0;
> +
> +err_free_hdl:
> + kfree(par);
> +
> + return ret;
> +}
> +
> +static const struct component_ops dcmipp_par_comp_ops = {
> + .bind = dcmipp_par_comp_bind,
> + .unbind = dcmipp_par_comp_unbind,
> +};
> +
> +static int dcmipp_par_probe(struct platform_device *pdev)
> +{
> + return component_add(&pdev->dev, &dcmipp_par_comp_ops);
> +}
> +
> +static int dcmipp_par_remove(struct platform_device *pdev)
> +{
> + component_del(&pdev->dev, &dcmipp_par_comp_ops);
> +
> + return 0;
> +}
> +
> +static const struct platform_device_id dcmipp_par_driver_ids[] = {
> + {
> + .name = DCMIPP_PAR_DRV_NAME,
> + },
> + { }
> +};
> +
> +static struct platform_driver dcmipp_par_pdrv = {
> + .probe = dcmipp_par_probe,
> + .remove = dcmipp_par_remove,
> + .id_table = dcmipp_par_driver_ids,
> + .driver = {
> + .name = DCMIPP_PAR_DRV_NAME,
> + },
> +};
> +
> +module_platform_driver(dcmipp_par_pdrv);
> +
> +MODULE_DEVICE_TABLE(platform, dcmipp_par_driver_ids);
> +
> +MODULE_AUTHOR("Hugues Fruchet <hugues.fruchet@xxxxxxxxxxx>");
> +MODULE_AUTHOR("Alain Volmat <hugues.fruchet@xxxxxxxxxxx>");
> +MODULE_DESCRIPTION("STMicroelectronics STM32 Digital Camera Memory Interface with Pixel Processor driver");
> +MODULE_LICENSE("GPL");

--
Kind regards,

Sakari Ailus