[PATCH v1 2/8] [media] stm32-dcmi: STM32 DCMI camera interface driver

From: Hugues Fruchet
Date: Wed Mar 29 2017 - 09:26:39 EST


This V4L2 subdev driver enables Digital Camera Memory Interface (DCMI)
of STMicroelectronics STM32 SoC series.

Signed-off-by: Yannick Fertre <yannick.fertre@xxxxxx>
Signed-off-by: Hugues Fruchet <hugues.fruchet@xxxxxx>
---
drivers/media/platform/Kconfig | 12 +
drivers/media/platform/Makefile | 2 +
drivers/media/platform/stm32/Makefile | 1 +
drivers/media/platform/stm32/stm32-dcmi.c | 1417 +++++++++++++++++++++++++++++
4 files changed, 1432 insertions(+)
create mode 100644 drivers/media/platform/stm32/Makefile
create mode 100644 drivers/media/platform/stm32/stm32-dcmi.c

diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
index ab0bb48..3421965 100644
--- a/drivers/media/platform/Kconfig
+++ b/drivers/media/platform/Kconfig
@@ -114,6 +114,18 @@ config VIDEO_S3C_CAMIF
To compile this driver as a module, choose M here: the module
will be called s3c-camif.

+config VIDEO_STM32_DCMI
+ tristate "Digital Camera Memory Interface (DCMI) support"
+ depends on VIDEO_V4L2 && OF && HAS_DMA
+ depends on ARCH_STM32 || COMPILE_TEST
+ select VIDEOBUF2_DMA_CONTIG
+ ---help---
+ This module makes the STM32 Digital Camera Memory Interface (DCMI)
+ available as a v4l2 device.
+
+ To compile this driver as a module, choose M here: the module
+ will be called stm32-dcmi.
+
source "drivers/media/platform/soc_camera/Kconfig"
source "drivers/media/platform/exynos4-is/Kconfig"
source "drivers/media/platform/am437x/Kconfig"
diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
index 8959f6e..d747715 100644
--- a/drivers/media/platform/Makefile
+++ b/drivers/media/platform/Makefile
@@ -64,6 +64,8 @@ obj-$(CONFIG_VIDEO_RCAR_VIN) += rcar-vin/

obj-$(CONFIG_VIDEO_ATMEL_ISC) += atmel/

+obj-$(CONFIG_VIDEO_STM32_DCMI) += stm32/
+
ccflags-y += -I$(srctree)/drivers/media/i2c

obj-$(CONFIG_VIDEO_MEDIATEK_VPU) += mtk-vpu/
diff --git a/drivers/media/platform/stm32/Makefile b/drivers/media/platform/stm32/Makefile
new file mode 100644
index 0000000..9b606a7
--- /dev/null
+++ b/drivers/media/platform/stm32/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_VIDEO_STM32_DCMI) += stm32-dcmi.o
diff --git a/drivers/media/platform/stm32/stm32-dcmi.c b/drivers/media/platform/stm32/stm32-dcmi.c
new file mode 100644
index 0000000..2f0286b
--- /dev/null
+++ b/drivers/media/platform/stm32/stm32-dcmi.c
@@ -0,0 +1,1417 @@
+/*
+ * Driver for STM32 Digital Camera Memory Interface
+ *
+ * Copyright (C) STMicroelectronics SA 2017
+ * Authors: Yannick Fertre <yannick.fertre@xxxxxx>
+ * Hugues Fruchet <hugues.fruchet@xxxxxx>
+ * for STMicroelectronics.
+ * License terms: GNU General Public License (GPL), version 2
+ *
+ * This driver is based on atmel_isi.c
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include <linux/videodev2.h>
+
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-dev.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-image-sizes.h>
+#include <media/v4l2-ioctl.h>
+#include <media/v4l2-of.h>
+#include <media/videobuf2-dma-contig.h>
+
+#define DRV_NAME "stm32-dcmi"
+
+/* Registers offset for DCMI */
+#define DCMI_CR 0x00 /* Control Register */
+#define DCMI_SR 0x04 /* Status Register */
+#define DCMI_RIS 0x08 /* Raw Interrupt Status register */
+#define DCMI_IER 0x0C /* Interrupt Enable Register */
+#define DCMI_MIS 0x10 /* Masked Interrupt Status register */
+#define DCMI_ICR 0x14 /* Interrupt Clear Register */
+#define DCMI_ESCR 0x18 /* Embedded Synchronization Code Register */
+#define DCMI_ESUR 0x1C /* Embedded Synchronization Unmask Register */
+#define DCMI_CWSTRT 0x20 /* Crop Window STaRT */
+#define DCMI_CWSIZE 0x24 /* Crop Window SIZE */
+#define DCMI_DR 0x28 /* Data Register */
+#define DCMI_IDR 0x2c /* IDentifier Register */
+
+/* Bits definition for control register (DCMI_CR) */
+#define CR_CAPTURE BIT(0)
+#define CR_CM BIT(1)
+#define CR_CROP BIT(2)
+#define CR_JPEG BIT(3)
+#define CR_ESS BIT(4)
+#define CR_PCKPOL BIT(5)
+#define CR_HSPOL BIT(6)
+#define CR_VSPOL BIT(7)
+#define CR_FCRC_0 BIT(8)
+#define CR_FCRC_1 BIT(9)
+#define CR_EDM_0 BIT(10)
+#define CR_EDM_1 BIT(11)
+#define CR_ENABLE BIT(14)
+
+/* Bits definition for status register (DCMI_SR) */
+#define SR_HSYNC BIT(0)
+#define SR_VSYNC BIT(1)
+#define SR_FNE BIT(2)
+
+/*
+ * Bits definition for interrupt registers
+ * (DCMI_RIS, DCMI_IER, DCMI_MIS, DCMI_ICR)
+ */
+#define IT_FRAME BIT(0)
+#define IT_OVR BIT(1)
+#define IT_ERR BIT(2)
+#define IT_VSYNC BIT(3)
+#define IT_LINE BIT(4)
+
+enum state {
+ STOPPED = 0,
+ RUNNING,
+ STOPPING,
+};
+
+#define MAX_BUS_WIDTH 14
+#define MAX_SUPPORT_WIDTH 2048
+#define MAX_SUPPORT_HEIGHT 2048
+#define MIN_SUPPORT_WIDTH 16
+#define MIN_SUPPORT_HEIGHT 16
+#define TIMEOUT_MS 1000
+
+struct dcmi_graph_entity {
+ struct device_node *node;
+
+ struct v4l2_async_subdev asd;
+ struct v4l2_subdev *subdev;
+};
+
+struct dcmi_format {
+ u32 fourcc;
+ u32 mbus_code;
+ u8 bpp;
+};
+
+struct dcmi_buf {
+ struct vb2_v4l2_buffer vb;
+ bool prepared;
+ dma_addr_t paddr;
+ size_t size;
+ struct list_head list;
+};
+
+struct stm32_dcmi {
+ spinlock_t irqlock;
+ struct device *dev;
+ void __iomem *regs;
+ struct resource *res;
+ struct reset_control *rstc;
+ int sequence;
+ struct list_head buffers;
+ struct dcmi_buf *active;
+
+ struct v4l2_device v4l2_dev;
+ struct video_device *vdev;
+ struct v4l2_async_notifier notifier;
+ struct dcmi_graph_entity entity;
+ struct v4l2_format fmt;
+
+ const struct dcmi_format **user_formats;
+ unsigned int num_user_formats;
+ const struct dcmi_format *current_fmt;
+
+ struct mutex lock;
+ struct vb2_queue queue;
+
+ struct v4l2_of_bus_parallel bus;
+ struct completion complete;
+ struct clk *mclk;
+ enum state state;
+ struct dma_chan *dma_chan;
+ dma_cookie_t dma_cookie;
+ u32 misr;
+ int errors_count;
+ int buffers_count;
+};
+
+static inline struct stm32_dcmi *notifier_to_dcmi(struct v4l2_async_notifier *n)
+{
+ return container_of(n, struct stm32_dcmi, notifier);
+}
+
+static inline u32 reg_read(void __iomem *base, u32 reg)
+{
+ return readl_relaxed(base + reg);
+}
+
+static inline void reg_write(void __iomem *base, u32 reg, u32 val)
+{
+ writel_relaxed(val, base + reg);
+}
+
+static inline void reg_set(void __iomem *base, u32 reg, u32 mask)
+{
+ reg_write(base, reg, reg_read(base, reg) | mask);
+}
+
+static inline void reg_clear(void __iomem *base, u32 reg, u32 mask)
+{
+ reg_write(base, reg, reg_read(base, reg) & ~mask);
+}
+
+static int dcmi_start_capture(struct stm32_dcmi *dcmi);
+
+static void dcmi_dma_callback(void *param)
+{
+ struct stm32_dcmi *dcmi = (struct stm32_dcmi *)param;
+ struct dma_chan *chan = dcmi->dma_chan;
+ struct dma_tx_state state;
+ enum dma_status status;
+
+ spin_lock(&dcmi->irqlock);
+
+ /* Check DMA status */
+ status = dmaengine_tx_status(chan, dcmi->dma_cookie, &state);
+
+ switch (status) {
+ case DMA_IN_PROGRESS:
+ dev_dbg(dcmi->dev, "%s: Received DMA_IN_PROGRESS\n", __func__);
+ break;
+ case DMA_PAUSED:
+ dev_err(dcmi->dev, "%s: Received DMA_PAUSED\n", __func__);
+ break;
+ case DMA_ERROR:
+ dev_err(dcmi->dev, "%s: Received DMA_ERROR\n", __func__);
+ break;
+ case DMA_COMPLETE:
+ dev_dbg(dcmi->dev, "%s: Received DMA_COMPLETE\n", __func__);
+
+ if (dcmi->active) {
+ struct dcmi_buf *buf = dcmi->active;
+ struct vb2_v4l2_buffer *vbuf = &dcmi->active->vb;
+
+ vbuf->sequence = dcmi->sequence++;
+ vbuf->field = V4L2_FIELD_NONE;
+ vbuf->vb2_buf.timestamp = ktime_get_ns();
+ vb2_set_plane_payload(&vbuf->vb2_buf, 0, buf->size);
+ vb2_buffer_done(&vbuf->vb2_buf, VB2_BUF_STATE_DONE);
+ dev_dbg(dcmi->dev, "buffer[%d] done seq=%d\n",
+ vbuf->vb2_buf.index, vbuf->sequence);
+
+ dcmi->buffers_count++;
+ dcmi->active = NULL;
+ }
+
+ /* Restart a new DMA transfer with next buffer */
+ if (dcmi->state == RUNNING) {
+ int ret;
+
+ if (list_empty(&dcmi->buffers)) {
+ dev_err(dcmi->dev, "%s: No more buffer queued, cannot capture buffer",
+ __func__);
+ dcmi->errors_count++;
+ dcmi->active = NULL;
+
+ spin_unlock(&dcmi->irqlock);
+ return;
+ }
+
+ dcmi->active = list_entry(dcmi->buffers.next,
+ struct dcmi_buf, list);
+
+ list_del_init(&dcmi->active->list);
+
+ ret = dcmi_start_capture(dcmi);
+ if (ret) {
+ dev_err(dcmi->dev, "%s: Cannot restart capture on DMA complete",
+ __func__);
+
+ spin_unlock(&dcmi->irqlock);
+ return;
+ }
+
+ /* Enable capture */
+ reg_set(dcmi->regs, DCMI_CR, CR_CAPTURE);
+ }
+
+ break;
+ default:
+ dev_err(dcmi->dev, "%s: Received unknown status\n", __func__);
+ break;
+ }
+
+ spin_unlock(&dcmi->irqlock);
+}
+
+static int dcmi_start_dma(struct stm32_dcmi *dcmi,
+ struct dcmi_buf *buf)
+{
+ struct dma_async_tx_descriptor *desc = NULL;
+ struct dma_slave_config config;
+ int ret;
+
+ memset(&config, 0, sizeof(config));
+
+ config.src_addr = (dma_addr_t)dcmi->res->start + DCMI_DR;
+ config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ config.dst_maxburst = 4;
+
+ /* Configure DMA channel */
+ ret = dmaengine_slave_config(dcmi->dma_chan, &config);
+ if (ret < 0) {
+ dev_err(dcmi->dev, "%s: DMA channel config failed (%d)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ /* Prepare a DMA transaction */
+ desc = dmaengine_prep_slave_single(dcmi->dma_chan, buf->paddr,
+ buf->size,
+ DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT);
+ if (!desc) {
+ dev_err(dcmi->dev, "%s: DMA dmaengine_prep_slave_single failed for buffer size %zu\n",
+ __func__, buf->size);
+ return -EINVAL;
+ }
+
+ /* Set completion callback routine for notification */
+ desc->callback = dcmi_dma_callback;
+ desc->callback_param = dcmi;
+
+ /* Push current DMA transaction in the pending queue */
+ dcmi->dma_cookie = dmaengine_submit(desc);
+
+ dma_async_issue_pending(dcmi->dma_chan);
+
+ return 0;
+}
+
+static int dcmi_start_capture(struct stm32_dcmi *dcmi)
+{
+ int ret;
+ struct dcmi_buf *buf = dcmi->active;
+
+ if (!buf)
+ return -EINVAL;
+
+ ret = dcmi_start_dma(dcmi, buf);
+ if (ret) {
+ vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
+ dcmi->errors_count++;
+ dcmi->active = NULL;
+
+ return ret;
+ }
+
+ /* Enable capture */
+ reg_set(dcmi->regs, DCMI_CR, CR_CAPTURE);
+
+ return 0;
+}
+
+static irqreturn_t dcmi_irq_thread(int irq, void *arg)
+{
+ struct stm32_dcmi *dcmi = arg;
+ int ret;
+
+ spin_lock(&dcmi->irqlock);
+
+ /* Stop capture is required */
+ if (dcmi->state == STOPPING) {
+ reg_clear(dcmi->regs, DCMI_IER, IT_FRAME | IT_OVR | IT_ERR);
+
+ dcmi->state = STOPPED;
+
+ complete(&dcmi->complete);
+
+ spin_unlock(&dcmi->irqlock);
+ return IRQ_HANDLED;
+ }
+
+ if ((dcmi->misr & IT_OVR) || (dcmi->misr & IT_ERR)) {
+ /*
+ * An overflow or an error has been detected,
+ * stop current DMA transfert & restart it
+ */
+ dev_warn(dcmi->dev, "%s: Overflow or error detected\n",
+ __func__);
+
+ dcmi->errors_count++;
+ dmaengine_terminate_all(dcmi->dma_chan);
+
+ reg_set(dcmi->regs, DCMI_ICR, IT_FRAME | IT_OVR | IT_ERR);
+
+ dev_dbg(dcmi->dev, "Restarting capture after DCMI error\n");
+
+ ret = dcmi_start_capture(dcmi);
+ if (ret) {
+ dev_err(dcmi->dev, "%s: Cannot restart capture on overflow or error\n",
+ __func__);
+
+ spin_unlock(&dcmi->irqlock);
+ return IRQ_HANDLED;
+ }
+ }
+
+ spin_unlock(&dcmi->irqlock);
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t dcmi_irq_callback(int irq, void *arg)
+{
+ struct stm32_dcmi *dcmi = arg;
+
+ spin_lock(&dcmi->irqlock);
+
+ dcmi->misr = reg_read(dcmi->regs, DCMI_MIS);
+
+ /* Clear interrupt */
+ reg_set(dcmi->regs, DCMI_ICR, IT_FRAME | IT_OVR | IT_ERR);
+
+ spin_unlock(&dcmi->irqlock);
+
+ return IRQ_WAKE_THREAD;
+}
+
+static int dcmi_queue_setup(struct vb2_queue *vq,
+ unsigned int *nbuffers,
+ unsigned int *nplanes,
+ unsigned int sizes[],
+ struct device *alloc_devs[])
+{
+ struct stm32_dcmi *dcmi = vb2_get_drv_priv(vq);
+ unsigned long size;
+
+ size = dcmi->fmt.fmt.pix.sizeimage;
+
+ /* Make sure the image size is large enough */
+ if (*nplanes)
+ return sizes[0] < size ? -EINVAL : 0;
+
+ *nplanes = 1;
+ sizes[0] = size;
+
+ dcmi->active = NULL;
+
+ dev_dbg(dcmi->dev, "Setup queue, count=%d, size=%ld\n",
+ *nbuffers, size);
+
+ return 0;
+}
+
+static int dcmi_buf_init(struct vb2_buffer *vb)
+{
+ struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+ struct dcmi_buf *buf = container_of(vbuf, struct dcmi_buf, vb);
+
+ INIT_LIST_HEAD(&buf->list);
+
+ return 0;
+}
+
+static int dcmi_buf_prepare(struct vb2_buffer *vb)
+{
+ struct stm32_dcmi *dcmi = vb2_get_drv_priv(vb->vb2_queue);
+ struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+ struct dcmi_buf *buf = container_of(vbuf, struct dcmi_buf, vb);
+ unsigned long size;
+
+ size = dcmi->fmt.fmt.pix.sizeimage;
+
+ if (vb2_plane_size(vb, 0) < size) {
+ dev_err(dcmi->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(dcmi->dev, "buffer[%d] phy=0x%pad size=%zu\n",
+ vb->index, &buf->paddr, buf->size);
+ }
+
+ return 0;
+}
+
+static void dcmi_buf_queue(struct vb2_buffer *vb)
+{
+ struct stm32_dcmi *dcmi = vb2_get_drv_priv(vb->vb2_queue);
+ struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+ struct dcmi_buf *buf = container_of(vbuf, struct dcmi_buf, vb);
+ unsigned long flags = 0;
+
+ spin_lock_irqsave(&dcmi->irqlock, flags);
+
+ if ((dcmi->state == RUNNING) && (!dcmi->active)) {
+ int ret;
+
+ dcmi->active = buf;
+
+ dev_dbg(dcmi->dev, "Starting capture on buffer[%d] queued\n",
+ buf->vb.vb2_buf.index);
+
+ ret = dcmi_start_capture(dcmi);
+ if (ret) {
+ dev_err(dcmi->dev, "%s: Cannot restart capture on overflow or error\n",
+ __func__);
+
+ spin_unlock_irqrestore(&dcmi->irqlock, flags);
+ return;
+ }
+ } else {
+ /* Enqueue to video buffers list */
+ list_add_tail(&buf->list, &dcmi->buffers);
+ }
+
+ spin_unlock_irqrestore(&dcmi->irqlock, flags);
+}
+
+static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
+{
+ struct stm32_dcmi *dcmi = vb2_get_drv_priv(vq);
+ struct dcmi_buf *buf, *node;
+ u32 val;
+ int ret;
+
+ /* Enable stream on the sub device */
+ ret = v4l2_subdev_call(dcmi->entity.subdev, video, s_stream, 1);
+ if (ret && ret != -ENOIOCTLCMD) {
+ dev_err(dcmi->dev, "%s: Failed to start streaming, subdev streamon error",
+ __func__);
+ goto err_release_buffers;
+ }
+
+ if (clk_enable(dcmi->mclk)) {
+ dev_err(dcmi->dev, "%s: Failed to start streaming, cannot enable clock",
+ __func__);
+ goto err_subdev_streamoff;
+ }
+
+ spin_lock_irq(&dcmi->irqlock);
+
+ val = reg_read(dcmi->regs, DCMI_CR);
+
+ val &= ~(CR_PCKPOL | CR_HSPOL | CR_VSPOL |
+ CR_EDM_0 | CR_EDM_1 | CR_FCRC_0 |
+ CR_FCRC_1 | CR_JPEG | CR_ESS);
+
+ /* Set bus width */
+ switch (dcmi->bus.bus_width) {
+ case 14:
+ val &= CR_EDM_0 + CR_EDM_1;
+ break;
+ case 12:
+ val &= CR_EDM_1;
+ break;
+ case 10:
+ val &= CR_EDM_0;
+ break;
+ default:
+ /* Set bus width to 8 bits by default */
+ break;
+ }
+
+ /* Set vertical synchronization polarity */
+ if (dcmi->bus.flags & V4L2_MBUS_VSYNC_ACTIVE_HIGH)
+ val |= CR_VSPOL;
+
+ /* Set horizontal synchronization polarity */
+ if (dcmi->bus.flags & V4L2_MBUS_HSYNC_ACTIVE_HIGH)
+ val |= CR_HSPOL;
+
+ /* Set pixel clock polarity */
+ if (dcmi->bus.flags & V4L2_MBUS_PCLK_SAMPLE_RISING)
+ val |= CR_PCKPOL;
+
+ reg_write(dcmi->regs, DCMI_CR, val);
+
+ /* Enable dcmi */
+ reg_set(dcmi->regs, DCMI_CR, CR_ENABLE);
+
+ dcmi->state = RUNNING;
+
+ dcmi->sequence = 0;
+ dcmi->errors_count = 0;
+ dcmi->buffers_count = 0;
+ dcmi->active = NULL;
+
+ /*
+ * Start transfer if at least one buffer has been queued,
+ * otherwise transfer is defered at buffer queueing
+ */
+ if (list_empty(&dcmi->buffers)) {
+ dev_dbg(dcmi->dev, "Start streaming is defered to next buffer queueing\n");
+ spin_unlock_irq(&dcmi->irqlock);
+ return 0;
+ }
+
+ dcmi->active = list_entry(dcmi->buffers.next, struct dcmi_buf, list);
+ list_del_init(&dcmi->active->list);
+
+ /* Enable interruptions */
+ reg_set(dcmi->regs, DCMI_IER, IT_FRAME | IT_OVR | IT_ERR);
+
+ dev_dbg(dcmi->dev, "Start streaming, starting capture\n");
+
+ ret = dcmi_start_capture(dcmi);
+ if (ret) {
+ dev_err(dcmi->dev, "%s: Start streaming failed, cannot start capture",
+ __func__);
+
+ spin_unlock_irq(&dcmi->irqlock);
+ goto err_subdev_streamoff;
+ }
+
+ spin_unlock_irq(&dcmi->irqlock);
+
+ return 0;
+
+err_subdev_streamoff:
+ v4l2_subdev_call(dcmi->entity.subdev, video, s_stream, 0);
+
+err_release_buffers:
+ spin_lock_irq(&dcmi->irqlock);
+ dcmi->active = NULL;
+ /*
+ * return all buffers to vb2 in QUEUED state.
+ * This will give ownership back to userspace
+ */
+ list_for_each_entry_safe(buf, node, &dcmi->buffers, list) {
+ list_del_init(&buf->list);
+ vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_QUEUED);
+ }
+ spin_unlock_irq(&dcmi->irqlock);
+
+ return ret;
+}
+
+static void dcmi_stop_streaming(struct vb2_queue *vq)
+{
+ struct stm32_dcmi *dcmi = vb2_get_drv_priv(vq);
+ struct dcmi_buf *buf, *node;
+ unsigned long time_ms = msecs_to_jiffies(TIMEOUT_MS);
+ long timeout;
+ int ret;
+
+ /* Disable stream on the sub device */
+ ret = v4l2_subdev_call(dcmi->entity.subdev, video, s_stream, 0);
+ if (ret && ret != -ENOIOCTLCMD)
+ dev_err(dcmi->dev, "stream off failed in subdev\n");
+
+ dcmi->state = STOPPING;
+
+ timeout = wait_for_completion_interruptible_timeout(&dcmi->complete,
+ time_ms);
+
+ spin_lock_irq(&dcmi->irqlock);
+
+ /* Disable interruptions */
+ reg_clear(dcmi->regs, DCMI_IER, IT_FRAME | IT_OVR | IT_ERR);
+
+ /* Disable DCMI */
+ reg_clear(dcmi->regs, DCMI_CR, CR_ENABLE);
+
+ if (!timeout) {
+ dev_err(dcmi->dev, "Timeout during stop streaming\n");
+ dcmi->state = STOPPED;
+ }
+
+ if (dcmi->active) {
+ buf = dcmi->active;
+ vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
+ dcmi->active = NULL;
+ }
+
+ /* Release all queued buffers */
+ list_for_each_entry_safe(buf, node, &dcmi->buffers, list) {
+ list_del_init(&buf->list);
+ vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
+ }
+
+ spin_unlock_irq(&dcmi->irqlock);
+
+ /* Stop all pending DMA operations */
+ dmaengine_terminate_all(dcmi->dma_chan);
+
+ clk_disable(dcmi->mclk);
+
+ dev_dbg(dcmi->dev, "Stop streaming, errors=%d buffers=%d\n",
+ dcmi->errors_count, dcmi->buffers_count);
+}
+
+static struct vb2_ops dcmi_video_qops = {
+ .queue_setup = dcmi_queue_setup,
+ .buf_init = dcmi_buf_init,
+ .buf_prepare = dcmi_buf_prepare,
+ .buf_queue = dcmi_buf_queue,
+ .start_streaming = dcmi_start_streaming,
+ .stop_streaming = dcmi_stop_streaming,
+ .wait_prepare = vb2_ops_wait_prepare,
+ .wait_finish = vb2_ops_wait_finish,
+};
+
+static int dcmi_g_fmt_vid_cap(struct file *file, void *priv,
+ struct v4l2_format *fmt)
+{
+ struct stm32_dcmi *dcmi = video_drvdata(file);
+
+ *fmt = dcmi->fmt;
+
+ return 0;
+}
+
+static const struct dcmi_format *find_format_by_fourcc(struct stm32_dcmi *dcmi,
+ unsigned int fourcc)
+{
+ unsigned int num_formats = dcmi->num_user_formats;
+ const struct dcmi_format *fmt;
+ unsigned int i;
+
+ for (i = 0; i < num_formats; i++) {
+ fmt = dcmi->user_formats[i];
+ if (fmt->fourcc == fourcc)
+ return fmt;
+ }
+
+ return NULL;
+}
+
+static int dcmi_try_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f,
+ const struct dcmi_format **current_fmt)
+{
+ const struct dcmi_format *dcmi_fmt;
+ struct v4l2_pix_format *pixfmt = &f->fmt.pix;
+ struct v4l2_subdev_pad_config pad_cfg;
+ struct v4l2_subdev_format format = {
+ .which = V4L2_SUBDEV_FORMAT_TRY,
+ };
+ int ret;
+
+ if (f->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+ return -EINVAL;
+
+ dcmi_fmt = find_format_by_fourcc(dcmi, pixfmt->pixelformat);
+ if (!dcmi_fmt) {
+ dcmi_fmt = dcmi->user_formats[dcmi->num_user_formats - 1];
+ pixfmt->pixelformat = dcmi_fmt->fourcc;
+ }
+
+ /* Limit to hardware capabilities */
+ if (pixfmt->width > MAX_SUPPORT_WIDTH)
+ pixfmt->width = MAX_SUPPORT_WIDTH;
+ if (pixfmt->height > MAX_SUPPORT_HEIGHT)
+ pixfmt->height = MAX_SUPPORT_HEIGHT;
+ if (pixfmt->width < MIN_SUPPORT_WIDTH)
+ pixfmt->width = MIN_SUPPORT_WIDTH;
+ if (pixfmt->height < MIN_SUPPORT_HEIGHT)
+ pixfmt->height = MIN_SUPPORT_HEIGHT;
+
+ v4l2_fill_mbus_format(&format.format, pixfmt, dcmi_fmt->mbus_code);
+ ret = v4l2_subdev_call(dcmi->entity.subdev, pad, set_fmt,
+ &pad_cfg, &format);
+ if (ret < 0)
+ return ret;
+
+ v4l2_fill_pix_format(pixfmt, &format.format);
+
+ pixfmt->field = V4L2_FIELD_NONE;
+ pixfmt->bytesperline = pixfmt->width * dcmi_fmt->bpp;
+ pixfmt->sizeimage = pixfmt->bytesperline * pixfmt->height;
+
+ if (current_fmt)
+ *current_fmt = dcmi_fmt;
+
+ return 0;
+}
+
+static int dcmi_set_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f)
+{
+ struct v4l2_subdev_format format = {
+ .which = V4L2_SUBDEV_FORMAT_ACTIVE,
+ };
+ const struct dcmi_format *current_fmt;
+ int ret;
+
+ ret = dcmi_try_fmt(dcmi, f, &current_fmt);
+ if (ret)
+ return ret;
+
+ v4l2_fill_mbus_format(&format.format, &f->fmt.pix,
+ current_fmt->mbus_code);
+ ret = v4l2_subdev_call(dcmi->entity.subdev, pad,
+ set_fmt, NULL, &format);
+ if (ret < 0)
+ return ret;
+
+ dcmi->fmt = *f;
+ dcmi->current_fmt = current_fmt;
+
+ return 0;
+}
+
+static int dcmi_s_fmt_vid_cap(struct file *file, void *priv,
+ struct v4l2_format *f)
+{
+ struct stm32_dcmi *dcmi = video_drvdata(file);
+
+ if (vb2_is_streaming(&dcmi->queue))
+ return -EBUSY;
+
+ return dcmi_set_fmt(dcmi, f);
+}
+
+static int dcmi_try_fmt_vid_cap(struct file *file, void *priv,
+ struct v4l2_format *f)
+{
+ struct stm32_dcmi *dcmi = video_drvdata(file);
+
+ return dcmi_try_fmt(dcmi, f, NULL);
+}
+
+static int dcmi_enum_fmt_vid_cap(struct file *file, void *priv,
+ struct v4l2_fmtdesc *f)
+{
+ struct stm32_dcmi *dcmi = video_drvdata(file);
+
+ if (f->index >= dcmi->num_user_formats)
+ return -EINVAL;
+
+ f->pixelformat = dcmi->user_formats[f->index]->fourcc;
+ return 0;
+}
+
+static int dcmi_querycap(struct file *file, void *priv,
+ struct v4l2_capability *cap)
+{
+ strlcpy(cap->driver, DRV_NAME, sizeof(cap->driver));
+ strlcpy(cap->card, "STM32 Digital Camera Memory Interface",
+ sizeof(cap->card));
+ strlcpy(cap->bus_info, "platform:dcmi", sizeof(cap->bus_info));
+ return 0;
+}
+
+static int dcmi_enum_input(struct file *file, void *priv,
+ struct v4l2_input *i)
+{
+ if (i->index != 0)
+ return -EINVAL;
+
+ i->type = V4L2_INPUT_TYPE_CAMERA;
+ strlcpy(i->name, "Camera", sizeof(i->name));
+ return 0;
+}
+
+static int dcmi_g_input(struct file *file, void *priv, unsigned int *i)
+{
+ *i = 0;
+ return 0;
+}
+
+static int dcmi_s_input(struct file *file, void *priv, unsigned int i)
+{
+ if (i > 0)
+ return -EINVAL;
+ return 0;
+}
+
+static int dcmi_enum_framesizes(struct file *file, void *fh,
+ struct v4l2_frmsizeenum *fsize)
+{
+ struct stm32_dcmi *dcmi = video_drvdata(file);
+ const struct dcmi_format *dcmi_fmt;
+ struct v4l2_subdev_frame_size_enum fse = {
+ .index = fsize->index,
+ .which = V4L2_SUBDEV_FORMAT_ACTIVE,
+ };
+ int ret;
+
+ dcmi_fmt = find_format_by_fourcc(dcmi, fsize->pixel_format);
+ if (!dcmi_fmt)
+ return -EINVAL;
+
+ fse.code = dcmi_fmt->mbus_code;
+
+ ret = v4l2_subdev_call(dcmi->entity.subdev, pad, enum_frame_size,
+ NULL, &fse);
+ if (ret)
+ return ret;
+
+ fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
+ fsize->discrete.width = fse.max_width;
+ fsize->discrete.height = fse.max_height;
+
+ return 0;
+}
+
+static int dcmi_enum_frameintervals(struct file *file, void *fh,
+ struct v4l2_frmivalenum *fival)
+{
+ struct stm32_dcmi *dcmi = video_drvdata(file);
+ const struct dcmi_format *dcmi_fmt;
+ struct v4l2_subdev_frame_interval_enum fie = {
+ .index = fival->index,
+ .width = fival->width,
+ .height = fival->height,
+ .which = V4L2_SUBDEV_FORMAT_ACTIVE,
+ };
+ int ret;
+
+ dcmi_fmt = find_format_by_fourcc(dcmi, fival->pixel_format);
+ if (!dcmi_fmt)
+ return -EINVAL;
+
+ fie.code = dcmi_fmt->mbus_code;
+
+ ret = v4l2_subdev_call(dcmi->entity.subdev, pad,
+ enum_frame_interval, NULL, &fie);
+ if (ret)
+ return ret;
+
+ fival->type = V4L2_FRMIVAL_TYPE_DISCRETE;
+ fival->discrete = fie.interval;
+
+ return 0;
+}
+
+static const struct of_device_id stm32_dcmi_of_match[] = {
+ { .compatible = "st,stm32-dcmi"},
+ { /* end node */ },
+};
+MODULE_DEVICE_TABLE(of, stm32_dcmi_of_match);
+
+static int dcmi_open(struct file *file)
+{
+ struct stm32_dcmi *dcmi = video_drvdata(file);
+ struct v4l2_subdev *sd = dcmi->entity.subdev;
+ int ret;
+
+ if (mutex_lock_interruptible(&dcmi->lock))
+ return -ERESTARTSYS;
+
+ ret = v4l2_fh_open(file);
+ if (ret < 0)
+ goto unlock;
+
+ if (!v4l2_fh_is_singular_file(file))
+ goto fh_rel;
+
+ ret = v4l2_subdev_call(sd, core, s_power, 1);
+ if (ret < 0 && ret != -ENOIOCTLCMD)
+ goto fh_rel;
+
+ ret = dcmi_set_fmt(dcmi, &dcmi->fmt);
+ if (ret)
+ v4l2_subdev_call(sd, core, s_power, 0);
+fh_rel:
+ if (ret)
+ v4l2_fh_release(file);
+unlock:
+ mutex_unlock(&dcmi->lock);
+ return ret;
+}
+
+static int dcmi_release(struct file *file)
+{
+ struct stm32_dcmi *dcmi = video_drvdata(file);
+ struct v4l2_subdev *sd = dcmi->entity.subdev;
+ bool fh_singular;
+ int ret;
+
+ mutex_lock(&dcmi->lock);
+
+ fh_singular = v4l2_fh_is_singular_file(file);
+
+ ret = _vb2_fop_release(file, NULL);
+
+ if (fh_singular)
+ v4l2_subdev_call(sd, core, s_power, 0);
+
+ mutex_unlock(&dcmi->lock);
+
+ return ret;
+}
+
+static const struct v4l2_ioctl_ops dcmi_ioctl_ops = {
+ .vidioc_querycap = dcmi_querycap,
+
+ .vidioc_try_fmt_vid_cap = dcmi_try_fmt_vid_cap,
+ .vidioc_g_fmt_vid_cap = dcmi_g_fmt_vid_cap,
+ .vidioc_s_fmt_vid_cap = dcmi_s_fmt_vid_cap,
+ .vidioc_enum_fmt_vid_cap = dcmi_enum_fmt_vid_cap,
+
+ .vidioc_enum_input = dcmi_enum_input,
+ .vidioc_g_input = dcmi_g_input,
+ .vidioc_s_input = dcmi_s_input,
+
+ .vidioc_enum_framesizes = dcmi_enum_framesizes,
+ .vidioc_enum_frameintervals = dcmi_enum_frameintervals,
+
+ .vidioc_reqbufs = vb2_ioctl_reqbufs,
+ .vidioc_create_bufs = vb2_ioctl_create_bufs,
+ .vidioc_querybuf = vb2_ioctl_querybuf,
+ .vidioc_qbuf = vb2_ioctl_qbuf,
+ .vidioc_dqbuf = vb2_ioctl_dqbuf,
+ .vidioc_expbuf = vb2_ioctl_expbuf,
+ .vidioc_prepare_buf = vb2_ioctl_prepare_buf,
+ .vidioc_streamon = vb2_ioctl_streamon,
+ .vidioc_streamoff = vb2_ioctl_streamoff,
+
+ .vidioc_log_status = v4l2_ctrl_log_status,
+ .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
+ .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
+};
+
+static const struct v4l2_file_operations dcmi_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = video_ioctl2,
+ .open = dcmi_open,
+ .release = dcmi_release,
+ .poll = vb2_fop_poll,
+ .mmap = vb2_fop_mmap,
+#ifndef CONFIG_MMU
+ .get_unmapped_area = vb2_fop_get_unmapped_area,
+#endif
+ .read = vb2_fop_read,
+};
+
+static int dcmi_set_default_fmt(struct stm32_dcmi *dcmi)
+{
+ struct v4l2_format f = {
+ .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
+ .fmt.pix = {
+ .width = CIF_WIDTH,
+ .height = CIF_HEIGHT,
+ .field = V4L2_FIELD_NONE,
+ .pixelformat = dcmi->user_formats[0]->fourcc,
+ },
+ };
+ int ret;
+
+ ret = dcmi_try_fmt(dcmi, &f, NULL);
+ if (ret)
+ return ret;
+ dcmi->current_fmt = dcmi->user_formats[0];
+ dcmi->fmt = f;
+ return 0;
+}
+
+static const struct dcmi_format dcmi_formats[] = {
+ {
+ .fourcc = V4L2_PIX_FMT_RGB565,
+ .mbus_code = MEDIA_BUS_FMT_RGB565_2X8_LE,
+ .bpp = 2,
+ }, {
+ .fourcc = V4L2_PIX_FMT_YUYV,
+ .mbus_code = MEDIA_BUS_FMT_YUYV8_2X8,
+ .bpp = 2,
+ }, {
+ .fourcc = V4L2_PIX_FMT_UYVY,
+ .mbus_code = MEDIA_BUS_FMT_UYVY8_2X8,
+ .bpp = 2,
+ },
+};
+
+static int dcmi_formats_init(struct stm32_dcmi *dcmi)
+{
+ const struct dcmi_format *dcmi_fmts[ARRAY_SIZE(dcmi_formats)];
+ unsigned int num_fmts = 0, i, j;
+ struct v4l2_subdev *subdev = dcmi->entity.subdev;
+ struct v4l2_subdev_mbus_code_enum mbus_code = {
+ .which = V4L2_SUBDEV_FORMAT_ACTIVE,
+ };
+
+ while (!v4l2_subdev_call(subdev, pad, enum_mbus_code,
+ NULL, &mbus_code)) {
+ for (i = 0; i < ARRAY_SIZE(dcmi_formats); i++) {
+ if (dcmi_formats[i].mbus_code != mbus_code.code)
+ continue;
+
+ /* Code supported, have we got this fourcc yet? */
+ for (j = 0; j < num_fmts; j++)
+ if (dcmi_fmts[j]->fourcc ==
+ dcmi_formats[i].fourcc)
+ /* Already available */
+ break;
+ if (j == num_fmts)
+ /* New */
+ dcmi_fmts[num_fmts++] = dcmi_formats + i;
+ }
+ mbus_code.index++;
+ }
+
+ if (!num_fmts)
+ return -ENXIO;
+
+ dcmi->num_user_formats = num_fmts;
+ dcmi->user_formats = devm_kcalloc(dcmi->dev,
+ num_fmts, sizeof(struct dcmi_format *),
+ GFP_KERNEL);
+ if (!dcmi->user_formats) {
+ dev_err(dcmi->dev, "could not allocate memory\n");
+ return -ENOMEM;
+ }
+
+ memcpy(dcmi->user_formats, dcmi_fmts,
+ num_fmts * sizeof(struct dcmi_format *));
+ dcmi->current_fmt = dcmi->user_formats[0];
+
+ return 0;
+}
+
+static int dcmi_graph_notify_complete(struct v4l2_async_notifier *notifier)
+{
+ struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
+ int ret;
+
+ dcmi->vdev->ctrl_handler = dcmi->entity.subdev->ctrl_handler;
+ ret = dcmi_formats_init(dcmi);
+ if (ret) {
+ dev_err(dcmi->dev, "No supported mediabus format found\n");
+ return ret;
+ }
+
+ ret = dcmi_set_default_fmt(dcmi);
+ if (ret) {
+ dev_err(dcmi->dev, "Could not set default format\n");
+ return ret;
+ }
+
+ ret = video_register_device(dcmi->vdev, VFL_TYPE_GRABBER, -1);
+ if (ret) {
+ dev_err(dcmi->dev, "Failed to register video device\n");
+ return ret;
+ }
+
+ dev_dbg(dcmi->dev, "Device registered as %s\n",
+ video_device_node_name(dcmi->vdev));
+ return 0;
+}
+
+static void dcmi_graph_notify_unbind(struct v4l2_async_notifier *notifier,
+ struct v4l2_subdev *sd,
+ struct v4l2_async_subdev *asd)
+{
+ struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
+
+ dev_dbg(dcmi->dev, "Removing %s\n", video_device_node_name(dcmi->vdev));
+
+ /* Checks internaly if vdev has been init or not */
+ video_unregister_device(dcmi->vdev);
+}
+
+static int dcmi_graph_notify_bound(struct v4l2_async_notifier *notifier,
+ struct v4l2_subdev *subdev,
+ struct v4l2_async_subdev *asd)
+{
+ struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
+
+ dev_dbg(dcmi->dev, "Subdev %s bound\n", subdev->name);
+
+ dcmi->entity.subdev = subdev;
+
+ return 0;
+}
+
+static int dcmi_graph_parse(struct stm32_dcmi *dcmi, struct device_node *node)
+{
+ struct device_node *ep = NULL;
+ struct device_node *remote;
+
+ while (1) {
+ ep = of_graph_get_next_endpoint(node, ep);
+ if (!ep)
+ return -EINVAL;
+
+ remote = of_graph_get_remote_port_parent(ep);
+ if (!remote) {
+ of_node_put(ep);
+ return -EINVAL;
+ }
+
+ /* Remote node to connect */
+ dcmi->entity.node = remote;
+ dcmi->entity.asd.match_type = V4L2_ASYNC_MATCH_OF;
+ dcmi->entity.asd.match.of.node = remote;
+ return 0;
+ }
+}
+
+static int dcmi_graph_init(struct stm32_dcmi *dcmi)
+{
+ struct v4l2_async_subdev **subdevs = NULL;
+ int ret;
+
+ /* Parse the graph to extract a list of subdevice DT nodes. */
+ ret = dcmi_graph_parse(dcmi, dcmi->dev->of_node);
+ if (ret < 0) {
+ dev_err(dcmi->dev, "Graph parsing failed\n");
+ return ret;
+ }
+
+ /* Register the subdevices notifier. */
+ subdevs = devm_kzalloc(dcmi->dev, sizeof(*subdevs), GFP_KERNEL);
+ if (!subdevs) {
+ of_node_put(dcmi->entity.node);
+ return -ENOMEM;
+ }
+
+ subdevs[0] = &dcmi->entity.asd;
+
+ dcmi->notifier.subdevs = subdevs;
+ dcmi->notifier.num_subdevs = 1;
+ dcmi->notifier.bound = dcmi_graph_notify_bound;
+ dcmi->notifier.unbind = dcmi_graph_notify_unbind;
+ dcmi->notifier.complete = dcmi_graph_notify_complete;
+
+ ret = v4l2_async_notifier_register(&dcmi->v4l2_dev, &dcmi->notifier);
+ if (ret < 0) {
+ dev_err(dcmi->dev, "Notifier registration failed\n");
+ of_node_put(dcmi->entity.node);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int dcmi_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ const struct of_device_id *match = NULL;
+ struct v4l2_of_endpoint ep;
+ struct stm32_dcmi *dcmi;
+ struct vb2_queue *q;
+ struct dma_chan *chan;
+ struct clk *mclk;
+ int irq;
+ int ret;
+
+ match = of_match_device(of_match_ptr(stm32_dcmi_of_match), &pdev->dev);
+ if (!match) {
+ dev_err(&pdev->dev, "Could not find a match in devicetree\n");
+ return -ENODEV;
+ }
+
+ dcmi = devm_kzalloc(&pdev->dev, sizeof(struct stm32_dcmi), GFP_KERNEL);
+ if (!dcmi)
+ return -ENOMEM;
+
+ dcmi->rstc = of_reset_control_get(np, NULL);
+ if (IS_ERR(dcmi->rstc)) {
+ dev_err(&pdev->dev, "Could not get reset control\n");
+ return -ENODEV;
+ }
+
+ /* Get bus characteristics from devicetree */
+ np = of_graph_get_next_endpoint(np, NULL);
+ if (!np) {
+ dev_err(&pdev->dev, "Could not find the endpoint\n");
+ of_node_put(np);
+ goto err_reset_control_put;
+ }
+
+ ret = v4l2_of_parse_endpoint(np, &ep);
+ if (ret) {
+ dev_err(&pdev->dev, "Could not parse the endpoint\n");
+ of_node_put(np);
+ goto err_reset_control_put;
+ }
+
+ if (ep.bus_type == V4L2_MBUS_CSI2) {
+ dev_err(&pdev->dev, "CSI bus not supported\n");
+ of_node_put(np);
+ goto err_reset_control_put;
+ }
+ dcmi->bus.flags = ep.bus.parallel.flags;
+ dcmi->bus.bus_width = ep.bus.parallel.bus_width;
+ dcmi->bus.data_shift = ep.bus.parallel.data_shift;
+
+ of_node_put(np);
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq <= 0) {
+ dev_err(&pdev->dev, "Could not get irq\n");
+ return -ENODEV;
+ }
+
+ dcmi->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!dcmi->res) {
+ dev_err(&pdev->dev, "Could not get resource\n");
+ return -ENODEV;
+ }
+
+ dcmi->regs = devm_ioremap_resource(&pdev->dev, dcmi->res);
+ if (IS_ERR(dcmi->regs)) {
+ dev_err(&pdev->dev, "Could not map registers\n");
+ return PTR_ERR(dcmi->regs);
+ }
+
+ ret = devm_request_threaded_irq(&pdev->dev, irq, dcmi_irq_callback,
+ dcmi_irq_thread, IRQF_ONESHOT,
+ dev_name(&pdev->dev), dcmi);
+ if (ret) {
+ dev_err(&pdev->dev, "Unable to request irq %d\n", irq);
+ return -ENODEV;
+ }
+
+ mclk = devm_clk_get(&pdev->dev, "mclk");
+ if (IS_ERR(mclk)) {
+ dev_err(&pdev->dev, "Unable to get mclk\n");
+ return PTR_ERR(mclk);
+ }
+
+ chan = dma_request_slave_channel(&pdev->dev, "tx");
+ if (!chan) {
+ dev_info(&pdev->dev, "Unable to request DMA channel, defer probing\n");
+ return -EPROBE_DEFER;
+ }
+
+ ret = clk_prepare(mclk);
+ if (ret) {
+ dev_err(&pdev->dev, "Unable to prepare mclk %p\n", mclk);
+ goto err_dma_release;
+ }
+
+ spin_lock_init(&dcmi->irqlock);
+ mutex_init(&dcmi->lock);
+ init_completion(&dcmi->complete);
+ INIT_LIST_HEAD(&dcmi->buffers);
+
+ dcmi->dev = &pdev->dev;
+ dcmi->mclk = mclk;
+ dcmi->state = STOPPED;
+ dcmi->dma_chan = chan;
+
+ q = &dcmi->queue;
+
+ /* Initialize the top-level structure */
+ ret = v4l2_device_register(&pdev->dev, &dcmi->v4l2_dev);
+ if (ret)
+ goto err_clk_unprepare;
+
+ dcmi->vdev = video_device_alloc();
+ if (!dcmi->vdev) {
+ ret = -ENOMEM;
+ goto err_device_unregister;
+ }
+
+ /* Video node */
+ dcmi->vdev->fops = &dcmi_fops;
+ dcmi->vdev->v4l2_dev = &dcmi->v4l2_dev;
+ dcmi->vdev->queue = &dcmi->queue;
+ strlcpy(dcmi->vdev->name, KBUILD_MODNAME, sizeof(dcmi->vdev->name));
+ dcmi->vdev->release = video_device_release;
+ dcmi->vdev->ioctl_ops = &dcmi_ioctl_ops;
+ dcmi->vdev->lock = &dcmi->lock;
+ dcmi->vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING |
+ V4L2_CAP_READWRITE;
+ video_set_drvdata(dcmi->vdev, dcmi);
+
+ /* Buffer queue */
+ q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+ q->io_modes = VB2_MMAP | VB2_READ | VB2_DMABUF;
+ q->lock = &dcmi->lock;
+ q->drv_priv = dcmi;
+ q->buf_struct_size = sizeof(struct dcmi_buf);
+ q->ops = &dcmi_video_qops;
+ q->mem_ops = &vb2_dma_contig_memops;
+ q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+ q->min_buffers_needed = 2;
+ q->dev = &pdev->dev;
+
+ ret = vb2_queue_init(q);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to initialize vb2 queue\n");
+ goto err_device_release;
+ }
+
+ ret = dcmi_graph_init(dcmi);
+ if (ret < 0)
+ goto err_device_release;
+
+ /* Reset device */
+ ret = reset_control_assert(dcmi->rstc);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to assert the reset line\n");
+ goto err_device_release;
+ }
+
+ usleep_range(3000, 5000);
+
+ ret = reset_control_deassert(dcmi->rstc);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to deassert the reset line\n");
+ goto err_device_release;
+ }
+
+ dev_info(&pdev->dev, "Probe done\n");
+
+ platform_set_drvdata(pdev, dcmi);
+ return 0;
+
+err_reset_control_put:
+ reset_control_put(dcmi->rstc);
+err_device_release:
+ video_device_release(dcmi->vdev);
+err_device_unregister:
+ v4l2_device_unregister(&dcmi->v4l2_dev);
+err_clk_unprepare:
+ clk_unprepare(dcmi->mclk);
+err_dma_release:
+ dma_release_channel(dcmi->dma_chan);
+
+ return ret;
+}
+
+static int dcmi_remove(struct platform_device *pdev)
+{
+ struct stm32_dcmi *dcmi = platform_get_drvdata(pdev);
+
+ v4l2_async_notifier_unregister(&dcmi->notifier);
+ v4l2_device_unregister(&dcmi->v4l2_dev);
+ clk_unprepare(dcmi->mclk);
+ dma_release_channel(dcmi->dma_chan);
+ reset_control_put(dcmi->rstc);
+
+ return 0;
+}
+
+static struct platform_driver stm32_dcmi_driver = {
+ .probe = dcmi_probe,
+ .remove = dcmi_remove,
+ .driver = {
+ .name = DRV_NAME,
+ .of_match_table = of_match_ptr(stm32_dcmi_of_match),
+ },
+};
+
+module_platform_driver(stm32_dcmi_driver);
+
+MODULE_AUTHOR("Yannick Fertre <yannick.fertre@xxxxxx>");
+MODULE_AUTHOR("Hugues Fruchet <hugues.fruchet@xxxxxx>");
+MODULE_DESCRIPTION("STMicroelectronics STM32 Digital Camera Memory Interface driver");
+MODULE_LICENSE("GPL");
+MODULE_SUPPORTED_DEVICE("video");
--
1.9.1