Re: [PATCH v3 01/10] media: Add Chameleon v3 video interface driver
From: Paweł Anikiel
Date: Mon Jun 03 2024 - 10:33:00 EST
On Mon, Jun 3, 2024 at 9:57 AM Hans Verkuil <hverkuil-cisco@xxxxxxxxx> wrote:
>
> On 07/05/2024 17:54, Paweł Anikiel wrote:
> > Add v4l2 driver for the video interface present on the Google
> > Chameleon v3. The Chameleon v3 uses the video interface to capture
> > a single video source from a given HDMI or DP connector and write
> > the resulting frames to memory.
> >
> > Signed-off-by: Paweł Anikiel <panikiel@xxxxxxxxxx>
> > ---
> > drivers/media/platform/Kconfig | 1 +
> > drivers/media/platform/Makefile | 1 +
> > drivers/media/platform/google/Kconfig | 13 +
> > drivers/media/platform/google/Makefile | 3 +
> > drivers/media/platform/google/chv3-video.c | 891 +++++++++++++++++++++
> > 5 files changed, 909 insertions(+)
> > create mode 100644 drivers/media/platform/google/Kconfig
> > create mode 100644 drivers/media/platform/google/Makefile
> > create mode 100644 drivers/media/platform/google/chv3-video.c
> >
> > diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> > index 91e54215de3a..b82f7b142b85 100644
> > --- a/drivers/media/platform/Kconfig
> > +++ b/drivers/media/platform/Kconfig
> > @@ -69,6 +69,7 @@ source "drivers/media/platform/aspeed/Kconfig"
> > source "drivers/media/platform/atmel/Kconfig"
> > source "drivers/media/platform/cadence/Kconfig"
> > source "drivers/media/platform/chips-media/Kconfig"
> > +source "drivers/media/platform/google/Kconfig"
> > source "drivers/media/platform/intel/Kconfig"
> > source "drivers/media/platform/marvell/Kconfig"
> > source "drivers/media/platform/mediatek/Kconfig"
> > diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
> > index 3296ec1ebe16..f7067eb05f76 100644
> > --- a/drivers/media/platform/Makefile
> > +++ b/drivers/media/platform/Makefile
> > @@ -12,6 +12,7 @@ obj-y += aspeed/
> > obj-y += atmel/
> > obj-y += cadence/
> > obj-y += chips-media/
> > +obj-y += google/
> > obj-y += intel/
> > obj-y += marvell/
> > obj-y += mediatek/
> > diff --git a/drivers/media/platform/google/Kconfig b/drivers/media/platform/google/Kconfig
> > new file mode 100644
> > index 000000000000..9674a4c12e2d
> > --- /dev/null
> > +++ b/drivers/media/platform/google/Kconfig
> > @@ -0,0 +1,13 @@
> > +# SPDX-License-Identifier: GPL-2.0-only
> > +
> > +config VIDEO_CHAMELEONV3
> > + tristate "Google Chameleon v3 video driver"
> > + depends on V4L_PLATFORM_DRIVERS
> > + depends on VIDEO_DEV
> > + select VIDEOBUF2_DMA_CONTIG
> > + select V4L2_FWNODE
> > + help
> > + v4l2 driver for the video interface present on the Google
> > + Chameleon v3. The Chameleon v3 uses the video interface to
> > + capture a single video source from a given HDMI or DP connector
> > + and write the resulting frames to memory.
> > diff --git a/drivers/media/platform/google/Makefile b/drivers/media/platform/google/Makefile
> > new file mode 100644
> > index 000000000000..cff06486244c
> > --- /dev/null
> > +++ b/drivers/media/platform/google/Makefile
> > @@ -0,0 +1,3 @@
> > +# SPDX-License-Identifier: GPL-2.0-only
> > +
> > +obj-$(CONFIG_VIDEO_CHAMELEONV3) += chv3-video.o
> > diff --git a/drivers/media/platform/google/chv3-video.c b/drivers/media/platform/google/chv3-video.c
> > new file mode 100644
> > index 000000000000..6e782484abaf
> > --- /dev/null
> > +++ b/drivers/media/platform/google/chv3-video.c
> > @@ -0,0 +1,891 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright 2023-2024 Google LLC.
> > + * Author: Paweł Anikiel <panikiel@xxxxxxxxxx>
> > + */
> > +
> > +#include <linux/delay.h>
> > +#include <linux/dma-mapping.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/kernel.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/v4l2-dv-timings.h>
> > +#include <linux/videodev2.h>
> > +#include <media/v4l2-ctrls.h>
> > +#include <media/v4l2-device.h>
> > +#include <media/v4l2-dv-timings.h>
> > +#include <media/v4l2-event.h>
> > +#include <media/v4l2-fwnode.h>
> > +#include <media/v4l2-ioctl.h>
> > +#include <media/videobuf2-dma-contig.h>
> > +
> > +#define DEVICE_NAME "chv3-video"
> > +
> > +#define VIDEO_EN 0x00
> > +#define VIDEO_EN_BIT BIT(0)
> > +#define VIDEO_HEIGHT 0x04
> > +#define VIDEO_WIDTH 0x08
> > +#define VIDEO_BUFFERA 0x0c
> > +#define VIDEO_BUFFERB 0x10
> > +#define VIDEO_BUFFERSIZE 0x14
> > +#define VIDEO_RESET 0x18
> > +#define VIDEO_RESET_BIT BIT(0)
> > +#define VIDEO_ERRORSTATUS 0x1c
> > +#define VIDEO_IOCOLOR 0x20
> > +#define VIDEO_DATARATE 0x24
> > +#define VIDEO_DATARATE_SINGLE 0x0
> > +#define VIDEO_DATARATE_DOUBLE 0x1
> > +#define VIDEO_PIXELMODE 0x28
> > +#define VIDEO_PIXELMODE_SINGLE 0x0
> > +#define VIDEO_PIXELMODE_DOUBLE 0x1
> > +#define VIDEO_SYNCPOLARITY 0x2c
> > +#define VIDEO_DMAFORMAT 0x30
> > +#define VIDEO_DMAFORMAT_8BPC 0x0
> > +#define VIDEO_DMAFORMAT_10BPC_UPPER 0x1
> > +#define VIDEO_DMAFORMAT_10BPC_LOWER 0x2
> > +#define VIDEO_DMAFORMAT_12BPC_UPPER 0x3
> > +#define VIDEO_DMAFORMAT_12BPC_LOWER 0x4
> > +#define VIDEO_DMAFORMAT_16BPC 0x5
> > +#define VIDEO_DMAFORMAT_RAW 0x6
> > +#define VIDEO_DMAFORMAT_8BPC_PAD 0x7
> > +#define VIDEO_VERSION 0x34
> > +#define VIDEO_VERSION_CURRENT 0xc0fb0001
> > +
> > +#define VIDEO_IRQ_MASK 0x8
> > +#define VIDEO_IRQ_CLR 0xc
> > +#define VIDEO_IRQ_ALL 0xf
> > +#define VIDEO_IRQ_BUFF0 BIT(0)
> > +#define VIDEO_IRQ_BUFF1 BIT(1)
> > +#define VIDEO_IRQ_RESOLUTION BIT(2)
> > +#define VIDEO_IRQ_ERROR BIT(3)
> > +
> > +struct chv3_video {
> > + struct device *dev;
> > + void __iomem *iobase;
> > + void __iomem *iobase_irq;
> > +
> > + struct v4l2_device v4l2_dev;
> > + struct vb2_queue queue;
> > + struct video_device vdev;
> > + struct v4l2_pix_format pix_fmt;
> > + struct v4l2_dv_timings timings;
> > + u32 bytes_per_pixel;
> > +
> > + struct v4l2_ctrl_handler ctrl_handler;
> > + struct v4l2_async_notifier notifier;
> > + struct v4l2_subdev *subdev;
> > + int subdev_source_pad;
> > +
> > + u32 sequence;
> > + bool writing_to_a;
> > +
> > + struct list_head bufs;
> > + spinlock_t bufs_lock;
> > +
> > + struct mutex video_lock;
> > +};
> > +
> > +struct chv3_video_buffer {
> > + struct vb2_v4l2_buffer vb;
> > + struct list_head link;
> > +};
> > +
> > +struct chv3_video_config {
> > + u32 pixelformat;
> > + u32 bytes_per_pixel;
> > + u32 dmaformat;
> > +};
> > +
> > +static void chv3_video_set_format_resolution(struct chv3_video *video, u32 width, u32 height)
> > +{
> > + video->pix_fmt.width = width;
> > + video->pix_fmt.height = height;
> > + video->pix_fmt.bytesperline = width * video->bytes_per_pixel;
> > + video->pix_fmt.sizeimage = video->pix_fmt.bytesperline * height;
> > +}
> > +
> > +/*
> > + * The video interface has hardware counters which expose the width and
> > + * height of the current video stream. It can't reliably detect if the stream
> > + * is present or not, so this is only used as a fallback in the case where
> > + * we don't have access to the receiver hardware.
> > + */
> > +static int chv3_video_query_dv_timings_fallback(struct chv3_video *video,
> > + struct v4l2_dv_timings *timings)
> > +{
> > + u32 width, height;
> > +
> > + width = readl(video->iobase + VIDEO_WIDTH);
> > + height = readl(video->iobase + VIDEO_HEIGHT);
> > + if (width == 0 || height == 0)
> > + return -ENOLINK;
> > +
> > + memset(timings, 0, sizeof(*timings));
> > + timings->type = V4L2_DV_BT_656_1120;
> > + timings->bt.width = width;
> > + timings->bt.height = height;
> > + timings->bt.pixelclock = width * height * 24;
> > +
> > + return 0;
> > +}
> > +
> > +static int chv3_video_query_dv_timings(struct chv3_video *video, struct v4l2_dv_timings *timings)
> > +{
> > + if (video->subdev) {
> > + return v4l2_subdev_call(video->subdev, pad, query_dv_timings,
> > + video->subdev_source_pad, timings);
> > + } else {
> > + return chv3_video_query_dv_timings_fallback(video, timings);
> > + }
>
> I would move the contents of chv3_video_query_dv_timings_fallback() to this
> function and drop the old fallback function. It makes more sense if it is all
> in the same function.
>
> > +}
> > +
> > +static const struct v4l2_dv_timings_cap chv3_video_fallback_dv_timings_cap = {
> > + .type = V4L2_DV_BT_656_1120,
> > + .bt = {
> > + .min_width = 640,
> > + .max_width = 7680,
> > + .min_height = 480,
> > + .max_height = 4320,
> > + .min_pixelclock = 25000000,
> > + .max_pixelclock = 1080000000,
> > + .standards = V4L2_DV_BT_STD_CEA861 | V4L2_DV_BT_STD_DMT |
> > + V4L2_DV_BT_STD_CVT | V4L2_DV_BT_STD_GTF,
> > + .capabilities = V4L2_DV_BT_CAP_PROGRESSIVE |
> > + V4L2_DV_BT_CAP_REDUCED_BLANKING |
> > + V4L2_DV_BT_CAP_CUSTOM,
> > + },
> > +};
> > +
> > +static int chv3_video_enum_dv_timings_fallback(struct chv3_video *video,
> > + struct v4l2_enum_dv_timings *timings)
> > +{
> > + return v4l2_enum_dv_timings_cap(timings, &chv3_video_fallback_dv_timings_cap,
> > + NULL, NULL);
> > +}
> > +
> > +static int chv3_video_dv_timings_cap_fallback(struct chv3_video *video,
> > + struct v4l2_dv_timings_cap *cap)
> > +{
> > + *cap = chv3_video_fallback_dv_timings_cap;
> > +
> > + return 0;
> > +}
>
> Same for these two fallback functions: move them to the functions that calls them.
>
> > +
> > +static void chv3_video_apply_dv_timings(struct chv3_video *video)
> > +{
> > + struct v4l2_dv_timings timings;
> > + int res;
> > +
> > + res = chv3_video_query_dv_timings(video, &timings);
> > + if (res)
> > + return;
> > +
> > + video->timings = timings;
> > + chv3_video_set_format_resolution(video, timings.bt.width, timings.bt.height);
> > +}
> > +
> > +static int chv3_video_querycap(struct file *file, void *fh, struct v4l2_capability *cap)
> > +{
> > + strscpy(cap->driver, DEVICE_NAME, sizeof(cap->driver));
> > + strscpy(cap->card, "Chameleon v3 video", sizeof(cap->card));
> > +
> > + return 0;
> > +}
> > +
> > +static int chv3_video_g_fmt_vid_cap(struct file *file, void *fh, struct v4l2_format *fmt)
> > +{
> > + struct chv3_video *video = video_drvdata(file);
> > +
> > + fmt->fmt.pix = video->pix_fmt;
> > +
> > + return 0;
> > +}
> > +
> > +static int chv3_video_enum_fmt_vid_cap(struct file *file, void *fh, struct v4l2_fmtdesc *fmt)
> > +{
> > + struct chv3_video *video = video_drvdata(file);
> > +
> > + if (fmt->index != 0)
> > + return -EINVAL;
> > +
> > + fmt->flags = 0;
> > + fmt->pixelformat = video->pix_fmt.pixelformat;
> > +
> > + return 0;
> > +}
> > +
> > +static int chv3_video_g_input(struct file *file, void *fh, unsigned int *index)
> > +{
> > + *index = 0;
> > +
> > + return 0;
> > +}
> > +
> > +static int chv3_video_s_input(struct file *file, void *fh, unsigned int index)
> > +{
> > + if (index != 0)
> > + return -EINVAL;
> > +
> > + return 0;
> > +}
> > +
> > +static int chv3_video_enum_input(struct file *file, void *fh, struct v4l2_input *input)
> > +{
> > + if (input->index != 0)
> > + return -EINVAL;
> > +
> > + strscpy(input->name, "input0", sizeof(input->name));
>
> This name is not terribly user friendly. Is it possible to determine a more human
> readable name? E.g. "DP1", "DP2", etc. Something that matches labeling on the Chameleon
> board.
The driver would require some board-specific instance info to
determine if the video interface is connected to DP1, DP2, or the
auxiliary decoder (or something entirely different if this IP was used
on a different board). I don't see an easy way to determine such a
human readable name, unfortunately.
>
> > + input->type = V4L2_INPUT_TYPE_CAMERA;
> > + input->capabilities = V4L2_IN_CAP_DV_TIMINGS;
> > +
> > + return 0;
> > +}
> > +
> > +static int chv3_video_g_edid(struct file *file, void *fh, struct v4l2_edid *edid)
> > +{
> > + struct chv3_video *video = video_drvdata(file);
> > + int res;
> > +
> > + if (!video->subdev)
> > + return -ENOTTY;
> > +
> > + if (edid->pad != 0)
> > + return -EINVAL;
> > +
> > + edid->pad = video->subdev_source_pad;
> > + res = v4l2_subdev_call(video->subdev, pad, get_edid, edid);
> > + edid->pad = 0;
> > +
> > + return res;
> > +}
> > +
> > +static int chv3_video_s_edid(struct file *file, void *fh, struct v4l2_edid *edid)
> > +{
> > + struct chv3_video *video = video_drvdata(file);
> > + int res;
> > +
> > + if (!video->subdev)
> > + return -ENOTTY;
> > +
> > + if (edid->pad != 0)
> > + return -EINVAL;
> > +
> > + edid->pad = video->subdev_source_pad;
> > + res = v4l2_subdev_call(video->subdev, pad, set_edid, edid);
> > + edid->pad = 0;
> > +
> > + return res;
> > +}
> > +
> > +static int chv3_video_s_dv_timings(struct file *file, void *fh, struct v4l2_dv_timings *timings)
> > +{
> > + struct chv3_video *video = video_drvdata(file);
> > +
> > + if (v4l2_match_dv_timings(&video->timings, timings, 0, false))
> > + return 0;
> > +
> > + if (vb2_is_busy(&video->queue))
> > + return -EBUSY;
>
> This should be moved to after the next 'if'.
>
> > +
> > + if (!v4l2_valid_dv_timings(timings, &chv3_video_fallback_dv_timings_cap, NULL, NULL))
> > + return -ERANGE;
> > +
> > + video->timings = *timings;
> > + chv3_video_set_format_resolution(video, timings->bt.width, timings->bt.height);
> > +
> > + return 0;
> > +}
> > +
> > +static int chv3_video_g_dv_timings(struct file *file, void *fh, struct v4l2_dv_timings *timings)
> > +{
> > + struct chv3_video *video = video_drvdata(file);
> > +
> > + *timings = video->timings;
> > + return 0;
> > +}
> > +
> > +static int chv3_video_vidioc_query_dv_timings(struct file *file, void *fh,
> > + struct v4l2_dv_timings *timings)
> > +{
> > + struct chv3_video *video = video_drvdata(file);
> > +
> > + return chv3_video_query_dv_timings(video, timings);
> > +}
> > +
> > +static int chv3_video_enum_dv_timings(struct file *file, void *fh,
> > + struct v4l2_enum_dv_timings *timings)
> > +{
> > + struct chv3_video *video = video_drvdata(file);
> > + int res;
> > +
> > + if (timings->pad != 0)
> > + return -EINVAL;
> > +
> > + if (video->subdev) {
> > + timings->pad = video->subdev_source_pad;
> > + res = v4l2_subdev_call(video->subdev, pad, enum_dv_timings, timings);
> > + timings->pad = 0;
> > + return res;
> > + } else {
> > + return chv3_video_enum_dv_timings_fallback(video, timings);
>
> It is much easier to read if the contents of chv3_video_enum_dv_timings_fallback
> is moved here.
>
> > + }
> > +}
> > +
> > +static int chv3_video_dv_timings_cap(struct file *file, void *fh, struct v4l2_dv_timings_cap *cap)
> > +{
> > + struct chv3_video *video = video_drvdata(file);
> > + int res;
> > +
> > + if (cap->pad != 0)
> > + return -EINVAL;
> > +
> > + if (video->subdev) {
> > + cap->pad = video->subdev_source_pad;
> > + res = v4l2_subdev_call(video->subdev, pad, dv_timings_cap, cap);
> > + cap->pad = 0;
> > + return res;
> > + } else {
> > + return chv3_video_dv_timings_cap_fallback(video, cap);
>
> Ditto.
>
> > + }
> > +}
> > +
> > +static int chv3_video_subscribe_event(struct v4l2_fh *fh,
> > + const struct v4l2_event_subscription *sub)
> > +{
> > + switch (sub->type) {
> > + case V4L2_EVENT_SOURCE_CHANGE:
> > + return v4l2_src_change_event_subscribe(fh, sub);
> > + }
> > +
> > + return v4l2_ctrl_subscribe_event(fh, sub);
> > +}
> > +
> > +static const struct v4l2_ioctl_ops chv3_video_v4l2_ioctl_ops = {
> > + .vidioc_querycap = chv3_video_querycap,
> > +
> > + .vidioc_enum_fmt_vid_cap = chv3_video_enum_fmt_vid_cap,
> > + .vidioc_g_fmt_vid_cap = chv3_video_g_fmt_vid_cap,
> > + .vidioc_s_fmt_vid_cap = chv3_video_g_fmt_vid_cap,
> > + .vidioc_try_fmt_vid_cap = chv3_video_g_fmt_vid_cap,
> > +
> > + .vidioc_enum_input = chv3_video_enum_input,
> > + .vidioc_g_input = chv3_video_g_input,
> > + .vidioc_s_input = chv3_video_s_input,
> > + .vidioc_g_edid = chv3_video_g_edid,
> > + .vidioc_s_edid = chv3_video_s_edid,
> > +
> > + .vidioc_reqbufs = vb2_ioctl_reqbufs,
> > + .vidioc_create_bufs = vb2_ioctl_create_bufs,
> > + .vidioc_querybuf = vb2_ioctl_querybuf,
> > + .vidioc_prepare_buf = vb2_ioctl_prepare_buf,
> > + .vidioc_expbuf = vb2_ioctl_expbuf,
> > + .vidioc_qbuf = vb2_ioctl_qbuf,
> > + .vidioc_dqbuf = vb2_ioctl_dqbuf,
> > + .vidioc_streamon = vb2_ioctl_streamon,
> > + .vidioc_streamoff = vb2_ioctl_streamoff,
> > +
> > + .vidioc_s_dv_timings = chv3_video_s_dv_timings,
> > + .vidioc_g_dv_timings = chv3_video_g_dv_timings,
> > + .vidioc_query_dv_timings = chv3_video_vidioc_query_dv_timings,
> > + .vidioc_enum_dv_timings = chv3_video_enum_dv_timings,
> > + .vidioc_dv_timings_cap = chv3_video_dv_timings_cap,
> > +
> > + .vidioc_subscribe_event = chv3_video_subscribe_event,
> > + .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
> > +};
> > +
> > +static int chv3_video_queue_setup(struct vb2_queue *q,
> > + unsigned int *nbuffers, unsigned int *nplanes,
> > + unsigned int sizes[], struct device *alloc_devs[])
> > +{
> > + struct chv3_video *video = vb2_get_drv_priv(q);
> > +
> > + if (*nplanes) {
> > + if (sizes[0] < video->pix_fmt.sizeimage)
> > + return -EINVAL;
> > + return 0;
> > + }
> > + *nplanes = 1;
> > + sizes[0] = video->pix_fmt.sizeimage;
> > +
> > + return 0;
> > +}
> > +
> > +/*
> > + * There are two address registers: BUFFERA and BUFFERB. The device
> > + * alternates writing between them (i.e. even frames go to BUFFERA, odd
> > + * ones to BUFFERB).
> > + *
> > + * (buffer queue) > QUEUED ---> QUEUED ---> QUEUED ---> ...
> > + * BUFFERA BUFFERB
> > + * (hw writing to this) ^
> > + * (and then to this) ^
> > + *
> > + * The buffer swapping happens at irq time. When an irq comes, the next
> > + * frame is already assigned an address in the buffer queue. This gives
> > + * the irq handler a whole frame's worth of time to update the buffer
> > + * address register.
> > + */
> > +
> > +static dma_addr_t chv3_video_buffer_dma_addr(struct chv3_video_buffer *buf)
> > +{
> > + return vb2_dma_contig_plane_dma_addr(&buf->vb.vb2_buf, 0);
> > +}
> > +
> > +static void chv3_video_start_frame(struct chv3_video *video, struct chv3_video_buffer *buf)
> > +{
> > + video->writing_to_a = 1;
> > + writel(chv3_video_buffer_dma_addr(buf), video->iobase + VIDEO_BUFFERA);
> > + writel(VIDEO_EN_BIT, video->iobase + VIDEO_EN);
> > +}
> > +
> > +static void chv3_video_next_frame(struct chv3_video *video, struct chv3_video_buffer *buf)
> > +{
> > + u32 reg = video->writing_to_a ? VIDEO_BUFFERB : VIDEO_BUFFERA;
> > +
> > + writel(chv3_video_buffer_dma_addr(buf), video->iobase + reg);
> > +}
> > +
> > +static int chv3_video_start_streaming(struct vb2_queue *q, unsigned int count)
> > +{
> > + struct chv3_video *video = vb2_get_drv_priv(q);
> > + struct chv3_video_buffer *buf;
> > + unsigned long flags;
> > +
> > + video->sequence = 0;
> > + writel(video->pix_fmt.sizeimage, video->iobase + VIDEO_BUFFERSIZE);
> > +
> > + spin_lock_irqsave(&video->bufs_lock, flags);
> > + buf = list_first_entry_or_null(&video->bufs, struct chv3_video_buffer, link);
> > + if (buf) {
> > + chv3_video_start_frame(video, buf);
> > + if (!list_is_last(&buf->link, &video->bufs))
> > + chv3_video_next_frame(video, list_next_entry(buf, link));
> > + }
> > + spin_unlock_irqrestore(&video->bufs_lock, flags);
> > +
> > + return 0;
> > +}
> > +
> > +static void chv3_video_stop_streaming(struct vb2_queue *q)
> > +{
> > + struct chv3_video *video = vb2_get_drv_priv(q);
> > + struct chv3_video_buffer *buf;
> > + unsigned long flags;
> > +
> > + writel(0, video->iobase + VIDEO_EN);
> > +
> > + spin_lock_irqsave(&video->bufs_lock, flags);
> > + list_for_each_entry(buf, &video->bufs, link)
> > + vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
> > + INIT_LIST_HEAD(&video->bufs);
> > + spin_unlock_irqrestore(&video->bufs_lock, flags);
> > +}
> > +
> > +static void chv3_video_buf_queue(struct vb2_buffer *vb)
> > +{
> > + struct chv3_video *video = vb2_get_drv_priv(vb->vb2_queue);
> > + struct vb2_v4l2_buffer *v4l2_buf = to_vb2_v4l2_buffer(vb);
> > + struct chv3_video_buffer *buf = container_of(v4l2_buf, struct chv3_video_buffer, vb);
> > + bool first, second;
> > + unsigned long flags;
> > +
> > + spin_lock_irqsave(&video->bufs_lock, flags);
> > + first = list_empty(&video->bufs);
> > + second = list_is_singular(&video->bufs);
> > + list_add_tail(&buf->link, &video->bufs);
> > + if (vb2_is_streaming(vb->vb2_queue)) {
>
> This should be vb2_start_streaming_called().
>
> It does not matter all that much in this driver, since VIDIOC_STREAMON will
> also call start_streaming, even if there are no buffers queued since the
> vb2_queue min_queued_buffers field is 0. But if that ever changes, then
> vb2_start_streaming_called() is the right call here.
Okay, I see. Should the other use of vb2_is_streaming() within this
file be replaced as well?
>
> > + if (first)
> > + chv3_video_start_frame(video, buf);
> > + else if (second)
> > + chv3_video_next_frame(video, buf);
> > + }
> > + spin_unlock_irqrestore(&video->bufs_lock, flags);
> > +}
> > +
> > +static const struct vb2_ops chv3_video_vb2_ops = {
> > + .queue_setup = chv3_video_queue_setup,
> > + .wait_prepare = vb2_ops_wait_prepare,
> > + .wait_finish = vb2_ops_wait_finish,
> > + .start_streaming = chv3_video_start_streaming,
> > + .stop_streaming = chv3_video_stop_streaming,
> > + .buf_queue = chv3_video_buf_queue,
> > +};
> > +
> > +static int chv3_video_open(struct file *file)
> > +{
> > + struct chv3_video *video = video_drvdata(file);
> > + int res;
> > +
> > + mutex_lock(&video->video_lock);
> > + res = v4l2_fh_open(file);
> > + if (!res) {
> > + if (v4l2_fh_is_singular_file(file))
> > + chv3_video_apply_dv_timings(video);
> > + }
> > + mutex_unlock(&video->video_lock);
> > +
> > + return res;
> > +}
> > +
> > +static const struct v4l2_file_operations chv3_video_v4l2_fops = {
> > + .owner = THIS_MODULE,
> > + .open = chv3_video_open,
> > + .release = vb2_fop_release,
> > + .unlocked_ioctl = video_ioctl2,
> > + .mmap = vb2_fop_mmap,
> > + .poll = vb2_fop_poll,
> > +};
> > +
> > +static void chv3_video_frame_irq(struct chv3_video *video)
> > +{
> > + struct chv3_video_buffer *buf;
> > +
> > + spin_lock(&video->bufs_lock);
> > +
> > + buf = list_first_entry_or_null(&video->bufs, struct chv3_video_buffer, link);
> > + if (!buf)
> > + goto empty;
> > + list_del(&buf->link);
> > +
> > + vb2_set_plane_payload(&buf->vb.vb2_buf, 0, video->pix_fmt.sizeimage);
> > + buf->vb.vb2_buf.timestamp = ktime_get_ns();
> > + buf->vb.sequence = video->sequence++;
> > + buf->vb.field = V4L2_FIELD_NONE;
> > + vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
> > +
> > + buf = list_first_entry_or_null(&video->bufs, struct chv3_video_buffer, link);
> > + if (buf) {
> > + video->writing_to_a = !video->writing_to_a;
> > + if (!list_is_last(&buf->link, &video->bufs))
> > + chv3_video_next_frame(video, list_next_entry(buf, link));
> > + } else {
> > + writel(0, video->iobase + VIDEO_EN);
> > + }
> > +empty:
> > + spin_unlock(&video->bufs_lock);
> > +}
> > +
> > +static void chv3_video_error_irq(struct chv3_video *video)
> > +{
> > + if (vb2_is_streaming(&video->queue))
> > + vb2_queue_error(&video->queue);
> > +}
> > +
> > +static void chv3_video_resolution_irq(struct chv3_video *video)
> > +{
> > + static const struct v4l2_event event = {
> > + .type = V4L2_EVENT_SOURCE_CHANGE,
> > + .u.src_change.changes = V4L2_EVENT_SRC_CH_RESOLUTION,
> > + };
> > +
> > + v4l2_event_queue(&video->vdev, &event);
> > + chv3_video_error_irq(video);
> > +}
> > +
> > +static irqreturn_t chv3_video_isr(int irq, void *data)
> > +{
> > + struct chv3_video *video = data;
> > + unsigned int reg;
> > +
> > + reg = readl(video->iobase_irq + VIDEO_IRQ_CLR);
> > + if (!reg)
> > + return IRQ_NONE;
> > +
> > + if (reg & VIDEO_IRQ_BUFF0)
> > + chv3_video_frame_irq(video);
> > + if (reg & VIDEO_IRQ_BUFF1)
> > + chv3_video_frame_irq(video);
> > + if (reg & VIDEO_IRQ_RESOLUTION)
> > + chv3_video_resolution_irq(video);
> > + if (reg & VIDEO_IRQ_ERROR) {
> > + dev_warn(video->dev, "error: 0x%x\n",
> > + readl(video->iobase + VIDEO_ERRORSTATUS));
> > + chv3_video_error_irq(video);
> > + }
> > +
> > + writel(reg, video->iobase_irq + VIDEO_IRQ_CLR);
> > +
> > + return IRQ_HANDLED;
> > +}
> > +
> > +static int chv3_video_check_version(struct chv3_video *video)
> > +{
> > + u32 version;
> > +
> > + version = readl(video->iobase + VIDEO_VERSION);
> > + if (version != VIDEO_VERSION_CURRENT) {
> > + dev_err(video->dev,
> > + "wrong hw version: expected %x, got %x\n",
> > + VIDEO_VERSION_CURRENT, version);
> > + return -ENODEV;
> > + }
> > + return 0;
> > +}
> > +
> > +static void chv3_video_init_timings_and_format(struct chv3_video *video,
> > + const struct chv3_video_config *config)
> > +{
> > + struct v4l2_pix_format *pix = &video->pix_fmt;
> > + struct v4l2_dv_timings timings = V4L2_DV_BT_CEA_1920X1080P60;
> > +
> > + video->timings = timings;
> > + video->bytes_per_pixel = config->bytes_per_pixel;
> > +
> > + pix->pixelformat = config->pixelformat;
> > + pix->field = V4L2_FIELD_NONE;
> > + pix->colorspace = V4L2_COLORSPACE_SRGB;
> > + chv3_video_set_format_resolution(video, timings.bt.width, timings.bt.height);
> > +}
> > +
> > +#define notifier_to_video(nf) container_of(nf, struct chv3_video, notifier)
> > +
> > +static int chv3_video_async_notify_bound(struct v4l2_async_notifier *notifier,
> > + struct v4l2_subdev *subdev,
> > + struct v4l2_async_connection *asc)
> > +{
> > + struct chv3_video *video = notifier_to_video(notifier);
> > + int pad;
> > +
> > + pad = media_entity_get_fwnode_pad(&subdev->entity, asc->match.fwnode,
> > + MEDIA_PAD_FL_SOURCE);
> > + if (pad < 0)
> > + return pad;
> > +
> > + video->subdev = subdev;
> > + video->subdev_source_pad = pad;
> > +
> > + video->v4l2_dev.ctrl_handler = subdev->ctrl_handler;
> > +
> > + return 0;
> > +}
> > +
> > +static void chv3_video_async_notify_unbind(struct v4l2_async_notifier *notifier,
> > + struct v4l2_subdev *subdev,
> > + struct v4l2_async_connection *asc)
> > +{
> > + struct chv3_video *video = notifier_to_video(notifier);
> > +
> > + vb2_video_unregister_device(&video->vdev);
> > +}
> > +
> > +static int chv3_video_async_notify_complete(struct v4l2_async_notifier *notifier)
> > +{
> > + struct chv3_video *video = notifier_to_video(notifier);
> > +
> > + return video_register_device(&video->vdev, VFL_TYPE_VIDEO, -1);
> > +}
> > +
> > +static const struct v4l2_async_notifier_operations chv3_video_async_notify_ops = {
> > + .bound = chv3_video_async_notify_bound,
> > + .unbind = chv3_video_async_notify_unbind,
> > + .complete = chv3_video_async_notify_complete,
> > +};
> > +
> > +static int chv3_video_fallback_init(struct chv3_video *video)
> > +{
> > + int res;
> > +
> > + video->subdev = NULL;
> > + video->subdev_source_pad = 0;
> > +
> > + v4l2_ctrl_handler_init(&video->ctrl_handler, 1);
> > + v4l2_ctrl_new_std(&video->ctrl_handler, NULL,
> > + V4L2_CID_DV_RX_POWER_PRESENT, 0, 1, 0, 0);
> > + res = video->ctrl_handler.error;
> > + if (res)
> > + goto handler_free;
> > +
> > + video->v4l2_dev.ctrl_handler = &video->ctrl_handler;
> > +
> > + res = video_register_device(&video->vdev, VFL_TYPE_VIDEO, -1);
> > + if (res)
> > + goto handler_free;
> > +
> > + return 0;
> > +
> > +handler_free:
> > + v4l2_ctrl_handler_free(&video->ctrl_handler);
> > +
> > + return res;
> > +}
> > +
> > +static int chv3_video_fwnode_init(struct chv3_video *video)
> > +{
> > + struct v4l2_async_connection *asc;
> > + struct fwnode_handle *endpoint;
> > + int res;
> > +
> > + endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(video->dev), NULL);
> > + if (!endpoint)
> > + return -EINVAL;
> > +
> > + v4l2_async_nf_init(&video->notifier, &video->v4l2_dev);
> > +
> > + asc = v4l2_async_nf_add_fwnode_remote(&video->notifier, endpoint,
> > + struct v4l2_async_connection);
> > + fwnode_handle_put(endpoint);
> > +
> > + if (IS_ERR(asc))
> > + return PTR_ERR(asc);
> > +
> > + video->notifier.ops = &chv3_video_async_notify_ops;
> > + res = v4l2_async_nf_register(&video->notifier);
> > + if (res) {
> > + v4l2_async_nf_cleanup(&video->notifier);
> > + return res;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int chv3_video_probe(struct platform_device *pdev)
> > +{
> > + struct chv3_video *video;
> > + const struct chv3_video_config *config;
> > + int res;
> > + int irq;
> > +
> > + video = devm_kzalloc(&pdev->dev, sizeof(*video), GFP_KERNEL);
> > + if (!video)
> > + return -ENOMEM;
> > + video->dev = &pdev->dev;
> > + platform_set_drvdata(pdev, video);
> > +
> > + config = device_get_match_data(video->dev);
> > +
> > + /* map register space */
> > + video->iobase = devm_platform_ioremap_resource(pdev, 0);
> > + if (IS_ERR(video->iobase))
> > + return PTR_ERR(video->iobase);
> > +
> > + video->iobase_irq = devm_platform_ioremap_resource(pdev, 1);
> > + if (IS_ERR(video->iobase_irq))
> > + return PTR_ERR(video->iobase_irq);
> > +
> > + /* check hw version */
> > + res = chv3_video_check_version(video);
> > + if (res)
> > + return res;
> > +
> > + /* setup interrupts */
> > + irq = platform_get_irq(pdev, 0);
> > + if (irq < 0)
> > + return -ENXIO;
> > + res = devm_request_irq(&pdev->dev, irq, chv3_video_isr, 0, DEVICE_NAME, video);
> > + if (res)
> > + return res;
> > +
> > + /* initialize v4l2_device */
> > + res = v4l2_device_register(&pdev->dev, &video->v4l2_dev);
> > + if (res)
> > + return res;
> > +
> > + /* initialize vb2 queue */
> > + video->queue.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
> > + video->queue.io_modes = VB2_MMAP | VB2_DMABUF;
> > + video->queue.dev = &pdev->dev;
> > + video->queue.lock = &video->video_lock;
> > + video->queue.ops = &chv3_video_vb2_ops;
> > + video->queue.mem_ops = &vb2_dma_contig_memops;
> > + video->queue.drv_priv = video;
> > + video->queue.buf_struct_size = sizeof(struct chv3_video_buffer);
> > + video->queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
> > + res = vb2_queue_init(&video->queue);
> > + if (res)
> > + goto error;
> > +
> > + /* initialize video_device */
> > + strscpy(video->vdev.name, DEVICE_NAME, sizeof(video->vdev.name));
> > + video->vdev.fops = &chv3_video_v4l2_fops;
> > + video->vdev.ioctl_ops = &chv3_video_v4l2_ioctl_ops;
> > + video->vdev.lock = &video->video_lock;
> > + video->vdev.release = video_device_release_empty;
> > + video->vdev.device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;
> > + video->vdev.v4l2_dev = &video->v4l2_dev;
> > + video->vdev.queue = &video->queue;
> > + video_set_drvdata(&video->vdev, video);
> > +
> > + if (device_get_named_child_node(&pdev->dev, "port"))
> > + res = chv3_video_fwnode_init(video);
> > + else
> > + res = chv3_video_fallback_init(video);
> > + if (res)
> > + goto error;
> > +
> > + /* initialize rest of driver struct */
> > + INIT_LIST_HEAD(&video->bufs);
> > + spin_lock_init(&video->bufs_lock);
> > + mutex_init(&video->video_lock);
> > +
> > + chv3_video_init_timings_and_format(video, config);
> > +
> > + /* initialize hw */
> > + writel(VIDEO_RESET_BIT, video->iobase + VIDEO_RESET);
> > + writel(VIDEO_DATARATE_DOUBLE, video->iobase + VIDEO_DATARATE);
> > + writel(VIDEO_PIXELMODE_DOUBLE, video->iobase + VIDEO_PIXELMODE);
> > + writel(config->dmaformat, video->iobase + VIDEO_DMAFORMAT);
> > +
> > + writel(VIDEO_IRQ_ALL, video->iobase_irq + VIDEO_IRQ_MASK);
> > +
> > + return 0;
> > +
> > +error:
> > + v4l2_device_unregister(&video->v4l2_dev);
> > +
> > + return res;
> > +}
> > +
> > +static void chv3_video_remove(struct platform_device *pdev)
> > +{
> > + struct chv3_video *video = platform_get_drvdata(pdev);
> > +
> > + /* disable interrupts */
> > + writel(0, video->iobase_irq + VIDEO_IRQ_MASK);
> > +
> > + if (video->subdev) {
> > + /* notifier is initialized only in non-fallback mode */
> > + v4l2_async_nf_unregister(&video->notifier);
> > + v4l2_async_nf_cleanup(&video->notifier);
> > + } else {
> > + /* ctrl handler is initialized only in fallback mode */
> > + v4l2_ctrl_handler_free(&video->ctrl_handler);
> > + }
> > +
> > + v4l2_device_unregister(&video->v4l2_dev);
> > +}
> > +
> > +static const struct chv3_video_config chv3_video_it = {
> > + .pixelformat = V4L2_PIX_FMT_BGRX32,
> > + .bytes_per_pixel = 4,
> > + .dmaformat = VIDEO_DMAFORMAT_8BPC_PAD,
> > +};
> > +
> > +static const struct chv3_video_config chv3_video_dp = {
> > + .pixelformat = V4L2_PIX_FMT_RGB24,
> > + .bytes_per_pixel = 3,
> > + .dmaformat = VIDEO_DMAFORMAT_8BPC,
> > +};
> > +
> > +static const struct of_device_id chv3_video_match_table[] = {
> > + { .compatible = "google,chv3-video-it-1.0", .data = &chv3_video_it },
> > + { .compatible = "google,chv3-video-dp-1.0", .data = &chv3_video_dp },
> > + { },
> > +};
> > +
> > +static struct platform_driver chv3_video_platform_driver = {
> > + .probe = chv3_video_probe,
> > + .remove_new = chv3_video_remove,
> > + .driver = {
> > + .name = DEVICE_NAME,
> > + .of_match_table = chv3_video_match_table,
> > + },
> > +};
> > +
> > +module_platform_driver(chv3_video_platform_driver);
> > +
> > +MODULE_AUTHOR("Paweł Anikiel <panikiel@xxxxxxxxxx>");
> > +MODULE_DESCRIPTION("Google Chameleon v3 video interface driver");
> > +MODULE_LICENSE("GPL");
>
> Regards,
>
> Hans