Re: [PATCH v6 4/6] media: starfive: Add video driver

From: Jack Zhu
Date: Fri Jun 16 2023 - 03:16:19 EST


Hi Laurent,

Thank you for your comments.

On 2023/6/1 20:59, Laurent Pinchart wrote:
> Hi Jack,
>
> Thank you for the patch.
>
> On Thu, May 25, 2023 at 04:32:00PM +0800, Jack Zhu wrote:
>> Add video driver for StarFive Camera Subsystem.
>>
>> Signed-off-by: Jack Zhu <jack.zhu@xxxxxxxxxxxxxxxx>
>> ---
>> drivers/media/platform/starfive/Makefile | 3 +-
>> drivers/media/platform/starfive/stf_video.c | 864 ++++++++++++++++++++
>> drivers/media/platform/starfive/stf_video.h | 95 +++
>> 3 files changed, 961 insertions(+), 1 deletion(-)
>> create mode 100644 drivers/media/platform/starfive/stf_video.c
>> create mode 100644 drivers/media/platform/starfive/stf_video.h
>>
>> diff --git a/drivers/media/platform/starfive/Makefile b/drivers/media/platform/starfive/Makefile
>> index 796775fa52f4..d7a42b3a938c 100644
>> --- a/drivers/media/platform/starfive/Makefile
>> +++ b/drivers/media/platform/starfive/Makefile
>> @@ -4,6 +4,7 @@
>> #
>>
>> starfive-camss-objs += \
>> - stf_camss.o
>> + stf_camss.o \
>> + stf_video.o
>>
>> obj-$(CONFIG_VIDEO_STARFIVE_CAMSS) += starfive-camss.o \
>> diff --git a/drivers/media/platform/starfive/stf_video.c b/drivers/media/platform/starfive/stf_video.c
>> new file mode 100644
>> index 000000000000..f027c7308dfb
>> --- /dev/null
>> +++ b/drivers/media/platform/starfive/stf_video.c
>> @@ -0,0 +1,864 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * stf_video.c
>> + *
>> + * StarFive Camera Subsystem - V4L2 device node
>> + *
>> + * Copyright (C) 2021-2023 StarFive Technology Co., Ltd.
>> + */
>> +
>> +#include <media/media-entity.h>
>> +#include <media/v4l2-ctrls.h>
>> +#include <media/v4l2-event.h>
>> +#include <media/v4l2-mc.h>
>> +#include <media/videobuf2-dma-contig.h>
>> +
>> +#include "stf_camss.h"
>> +#include "stf_video.h"
>> +
>> +static const struct stfcamss_format_info formats_pix_wr[] = {
>> + { MEDIA_BUS_FMT_SRGGB10_1X10, V4L2_PIX_FMT_SRGGB10, 1,
>> + { { 1, 1 } }, { { 1, 1 } }, { 10 } },
>> + { MEDIA_BUS_FMT_SGRBG10_1X10, V4L2_PIX_FMT_SGRBG10, 1,
>> + { { 1, 1 } }, { { 1, 1 } }, { 10 } },
>> + { MEDIA_BUS_FMT_SGBRG10_1X10, V4L2_PIX_FMT_SGBRG10, 1,
>> + { { 1, 1 } }, { { 1, 1 } }, { 10 } },
>> + { MEDIA_BUS_FMT_SBGGR10_1X10, V4L2_PIX_FMT_SBGGR10, 1,
>> + { { 1, 1 } }, { { 1, 1 } }, { 10 } },
>> +};
>> +
>> +static const struct stfcamss_format_info formats_pix_isp[] = {
>> + { MEDIA_BUS_FMT_Y12_1X12, V4L2_PIX_FMT_NV12, 1,
>> + { { 1, 1 } }, { { 2, 3 } }, { 8 } },
>
> The [hv]sub values look weird. NV12 subsamples by 2 in both directions
> for the chroma plane. The result of your bytesperline calculation is
> right before the chroma plane is subsampled by 2 horizontally, but
> contains both U and V components, so the number of bytes equals the
> width in pixels for both the luma and chroma planes. In the vertical
> direction, the calculation is fine too for NV12 as you're calculating
> sizeimage for both planes.
>
> I would recommend something along the following lines:
>
> struct stfcamss_format_info {
> u32 code;
> u32 pixelformat;
> u8 planes;
> u8 vsub[3];
> u8 bpp;
> };
>
> static const struct stfcamss_format_info formats_pix_isp[] = {
> {
> .code = MEDIA_BUS_FMT_Y12_1X12,
> .pixelformat = V4L2_PIX_FMT_NV12,
> .planes = 2,
> .vsub = { 1, 2 },
> .bpp = 8,
> },
> };
>
> {
> unsigned int bytesperline;
> unsigned int sizeimage = 0;
>
> bytesperline = width * info->bpp / 8;
>
> for (i = 0; i < info->planes; ++i)
> sizeimage += bytesperline * height / info->vsub[i];
> }
>

Okay, I will fix it.

>> +};
>> +
>> +/* -----------------------------------------------------------------------------
>> + * Helper functions
>> + */
>> +
>> +static int video_find_format(u32 code, u32 pixelformat,
>> + const struct stfcamss_format_info *formats,
>> + unsigned int nformats)
>
> I would pass the stfcamss_video pointer to this function instead of
> formats and nformats.
>

Okay, I will modify the function.

>> +{
>> + int i;
>> +
>> + for (i = 0; i < nformats; i++) {
>> + if (formats[i].code == code &&
>> + formats[i].pixelformat == pixelformat)
>> + return i;
>> + }
>> +
>> + for (i = 0; i < nformats; i++)
>> + if (formats[i].code == code)
>> + return i;
>> +
>> + for (i = 0; i < nformats; i++)
>> + if (formats[i].pixelformat == pixelformat)
>> + return i;
>> +
>> + return -EINVAL;
>> +}
>> +
>> +static int __video_try_fmt(struct stfcamss_video *video, struct v4l2_format *f)
>> +{
>> + struct v4l2_pix_format *pix;
>> + const struct stfcamss_format_info *fi;
>> + u32 width, height;
>> + u32 bpl;
>> + int i;
>> +
>> + pix = &f->fmt.pix;
>> +
>> + for (i = 0; i < video->nformats; i++)
>> + if (pix->pixelformat == video->formats[i].pixelformat)
>> + break;
>> +
>> + if (i == video->nformats)
>> + i = 0; /* default format */
>> +
>> + fi = &video->formats[i];
>> + width = pix->width;
>> + height = pix->height;
>> +
>> + memset(pix, 0, sizeof(*pix));
>> +
>> + pix->pixelformat = fi->pixelformat;
>> + pix->width = clamp_t(u32, width, STFCAMSS_FRAME_MIN_WIDTH,
>> + STFCAMSS_FRAME_MAX_WIDTH);
>> + pix->height = clamp_t(u32, height, STFCAMSS_FRAME_MIN_HEIGHT,
>> + STFCAMSS_FRAME_MAX_HEIGHT);
>> + bpl = pix->width / fi->hsub[0].numerator *
>> + fi->hsub[0].denominator * fi->bpp[0] / 8;
>> + bpl = ALIGN(bpl, video->bpl_alignment);
>> + pix->bytesperline = bpl;
>> + pix->sizeimage = pix->height / fi->vsub[0].numerator *
>> + fi->vsub[0].denominator * bpl;
>> +
>> + pix->field = V4L2_FIELD_NONE;
>> + pix->colorspace = V4L2_COLORSPACE_SRGB;
>> + pix->flags = 0;
>> + pix->ycbcr_enc =
>> + V4L2_MAP_YCBCR_ENC_DEFAULT(pix->colorspace);
>> + pix->quantization = V4L2_MAP_QUANTIZATION_DEFAULT(true,
>> + pix->colorspace,
>> + pix->ycbcr_enc);
>> + pix->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(pix->colorspace);
>> +
>> + return 0;
>> +}
>> +
>> +static int stf_video_init_format(struct stfcamss_video *video)
>> +{
>> + int ret;
>> + struct v4l2_format format = {
>> + .type = video->type,
>> + .fmt.pix = {
>> + .width = 1920,
>> + .height = 1080,
>> + .pixelformat = V4L2_PIX_FMT_RGB565,
>> + },
>> + };
>> +
>> + ret = __video_try_fmt(video, &format);
>> +
>> + if (ret < 0)
>> + return ret;
>> +
>> + video->active_fmt = format;
>> +
>> + return 0;
>> +}
>> +
>> +/* -----------------------------------------------------------------------------
>> + * Video queue operations
>> + */
>> +
>> +static int video_queue_setup(struct vb2_queue *q,
>> + unsigned int *num_buffers,
>> + unsigned int *num_planes,
>> + unsigned int sizes[],
>> + struct device *alloc_devs[])
>> +{
>> + struct stfcamss_video *video = vb2_get_drv_priv(q);
>> + const struct v4l2_pix_format *format = &video->active_fmt.fmt.pix;
>> +
>> + if (*num_planes) {
>> + if (*num_planes != 1)
>> + return -EINVAL;
>> +
>> + if (sizes[0] < format->sizeimage)
>> + return -EINVAL;
>> + }
>> +
>> + *num_planes = 1;
>> + sizes[0] = format->sizeimage;
>> + if (!sizes[0])
>> + dev_err(video->stfcamss->dev,
>> + "%s: error size is zero!!!\n", __func__);
>> +
>> + dev_dbg(video->stfcamss->dev, "planes = %d, size = %d\n",
>> + *num_planes, sizes[0]);
>> +
>> + return 0;
>> +}
>> +
>> +static int video_buf_init(struct vb2_buffer *vb)
>> +{
>> + struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
>> + struct stfcamss_video *video = vb2_get_drv_priv(vb->vb2_queue);
>> + struct stfcamss_buffer *buffer =
>> + container_of(vbuf, struct stfcamss_buffer, vb);
>> + const struct v4l2_pix_format *fmt = &video->active_fmt.fmt.pix;
>> + dma_addr_t *paddr;
>> +
>> + buffer->sizeimage = 0;
>> +
>> + paddr = vb2_plane_cookie(vb, 0);
>> + buffer->sizeimage = vb2_plane_size(vb, 0);
>> + buffer->addr[0] = *paddr;
>> + if (fmt->pixelformat == V4L2_PIX_FMT_NV12 ||
>> + fmt->pixelformat == V4L2_PIX_FMT_NV21 ||
>> + fmt->pixelformat == V4L2_PIX_FMT_NV16 ||
>> + fmt->pixelformat == V4L2_PIX_FMT_NV61)
>> + buffer->addr[1] =
>> + buffer->addr[0] + fmt->bytesperline * fmt->height;
>> +
>> + return 0;
>> +}
>> +
>> +static int video_buf_prepare(struct vb2_buffer *vb)
>> +{
>> + struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
>> + struct stfcamss_video *video = vb2_get_drv_priv(vb->vb2_queue);
>> + const struct v4l2_pix_format *fmt = &video->active_fmt.fmt.pix;
>> +
>> + if (fmt->sizeimage > vb2_plane_size(vb, 0)) {
>> + dev_err(video->stfcamss->dev,
>> + "sizeimage = %d, plane size = %d\n",
>> + fmt->sizeimage, (unsigned int)vb2_plane_size(vb, 0));
>> + return -EINVAL;
>> + }
>> + vb2_set_plane_payload(vb, 0, fmt->sizeimage);
>> +
>> + vbuf->field = V4L2_FIELD_NONE;
>> +
>> + return 0;
>> +}
>> +
>> +static void video_buf_queue(struct vb2_buffer *vb)
>> +{
>> + struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
>> + struct stfcamss_video *video = vb2_get_drv_priv(vb->vb2_queue);
>> + struct stfcamss_buffer *buffer =
>> + container_of(vbuf, struct stfcamss_buffer, vb);
>> +
>> + video->ops->queue_buffer(video, buffer);
>> +}
>> +
>> +/*
>> + * video_mbus_to_pix - Convert v4l2_mbus_framefmt to v4l2_pix_format
>> + * @mbus: v4l2_mbus_framefmt format (input)
>> + * @pix: v4l2_pix_format_mplane format (output)
>> + * @f: a pointer to formats array element to be used for the conversion
>> + * @alignment: bytesperline alignment value
>> + *
>> + * Fill the output pix structure with information from the input mbus format.
>> + *
>> + * Return 0 on success or a negative error code otherwise
>> + */
>> +static int video_mbus_to_pix(const struct v4l2_mbus_framefmt *mbus,
>> + struct v4l2_pix_format *pix,
>> + const struct stfcamss_format_info *f,
>> + unsigned int alignment)
>> +{
>> + u32 bytesperline;
>> +
>> + memset(pix, 0, sizeof(*pix));
>> + v4l2_fill_pix_format(pix, mbus);
>> + pix->pixelformat = f->pixelformat;
>> + bytesperline = pix->width / f->hsub[0].numerator *
>> + f->hsub[0].denominator * f->bpp[0] / 8;
>> + bytesperline = ALIGN(bytesperline, alignment);
>> + pix->bytesperline = bytesperline;
>> + pix->sizeimage = pix->height / f->vsub[0].numerator *
>> + f->vsub[0].denominator * bytesperline;
>> + return 0;
>> +}
>> +
>> +static struct v4l2_subdev *video_remote_subdev(struct stfcamss_video *video,
>> + u32 *pad)
>> +{
>> + struct media_pad *remote;
>> +
>> + remote = media_pad_remote_pad_first(&video->pad);
>> +
>> + if (!remote || !is_media_entity_v4l2_subdev(remote->entity))
>> + return NULL;
>> +
>> + if (pad)
>> + *pad = remote->index;
>> +
>> + return media_entity_to_v4l2_subdev(remote->entity);
>> +}
>> +
>> +static int video_get_subdev_format(struct stfcamss_video *video,
>> + struct v4l2_format *format)
>> +{
>> + struct v4l2_pix_format *pix = &video->active_fmt.fmt.pix;
>> + struct v4l2_subdev_format fmt;
>> + struct v4l2_subdev *subdev;
>> + u32 pixelformat;
>> + u32 pad;
>> + int ret;
>> +
>> + subdev = video_remote_subdev(video, &pad);
>> + if (!subdev)
>> + return -EPIPE;
>> +
>> + fmt.pad = pad;
>> + fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
>> +
>> + ret = v4l2_subdev_call(subdev, pad, get_fmt, NULL, &fmt);
>> + if (ret)
>> + return ret;
>> +
>> + pixelformat = pix->pixelformat;
>> + ret = video_find_format(fmt.format.code, pixelformat,
>> + video->formats, video->nformats);
>> + if (ret < 0)
>> + return ret;
>> +
>> + format->type = video->type;
>> +
>> + return video_mbus_to_pix(&fmt.format, &format->fmt.pix,
>> + &video->formats[ret], video->bpl_alignment);
>> +}
>> +
>> +static int video_check_format(struct stfcamss_video *video)
>> +{
>> + struct v4l2_pix_format *pix = &video->active_fmt.fmt.pix;
>> + struct v4l2_format format;
>> + struct v4l2_pix_format *sd_pix = &format.fmt.pix;
>> + int ret;
>> +
>> + sd_pix->pixelformat = pix->pixelformat;
>> + ret = video_get_subdev_format(video, &format);
>> + if (ret < 0)
>> + return ret;
>> +
>> + if (pix->pixelformat != sd_pix->pixelformat ||
>> + pix->height > sd_pix->height ||
>> + pix->width > sd_pix->width ||
>
> The width and height must be identical.
>

Okay, I will fix it.

>> + pix->field != format.fmt.pix.field) {
>> + dev_err(video->stfcamss->dev,
>> + "%s, not match:\n"
>> + "0x%x 0x%x\n0x%x 0x%x\n0x%x 0x%x\n",
>> + __func__,
>> + pix->pixelformat, sd_pix->pixelformat,
>> + pix->height, sd_pix->height,
>> + pix->field, format.fmt.pix.field);
>> + return -EPIPE;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int video_start_streaming(struct vb2_queue *q, unsigned int count)
>> +{
>> + struct stfcamss_video *video = vb2_get_drv_priv(q);
>> + struct video_device *vdev = &video->vdev;
>> + struct media_entity *entity;
>> + struct media_pad *pad;
>> + struct v4l2_subdev *subdev;
>> + int ret;
>> +
>> + ret = video_device_pipeline_start(vdev, &video->stfcamss->pipe);
>> + if (ret < 0) {
>> + dev_err(video->stfcamss->dev,
>> + "Failed to media_pipeline_start: %d\n", ret);
>> + return ret;
>> + }
>> +
>> + ret = video_check_format(video);
>> + if (ret < 0)
>> + goto error;
>> + entity = &vdev->entity;
>> + 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, 1);
>> + if (ret < 0 && ret != -ENOIOCTLCMD)
>> + goto error;
>> + }
>
> While you're free to decide how to implement the start streaming
> operation for all the subdevs in your driver, you must not call
> .s_stream() on all *external* subdevs. Imagine a case where the device
> connected to your VIN input would be a parallel-to-CSI-2 bridge. This
> driver must call .s_stream() on the bridge, but must not call
> .s_stream() on the device at the input of the bridge, as the bridge
> driver will propagate the .s_stream() call itself.
>
> I will be able to advice better on how to handle stream start once you
> provide the media graph of the device.
>

Okay, I will provide the media graph of the device.

>> + return 0;
>> +
>> +error:
>> + video_device_pipeline_stop(vdev);
>> + video->ops->flush_buffers(video, VB2_BUF_STATE_QUEUED);
>> + return ret;
>> +}
>> +
>> +static void video_stop_streaming(struct vb2_queue *q)
>> +{
>> + struct stfcamss_video *video = vb2_get_drv_priv(q);
>> + struct video_device *vdev = &video->vdev;
>> + struct media_entity *entity;
>> + struct media_pad *pad;
>> + struct v4l2_subdev *subdev;
>> +
>> + entity = &vdev->entity;
>> + 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);
>> +
>> + v4l2_subdev_call(subdev, video, s_stream, 0);
>> + }
>> +
>> + video_device_pipeline_stop(vdev);
>> + video->ops->flush_buffers(video, VB2_BUF_STATE_ERROR);
>> +}
>> +
>> +static const struct vb2_ops stf_video_vb2_q_ops = {
>> + .queue_setup = video_queue_setup,
>> + .wait_prepare = vb2_ops_wait_prepare,
>> + .wait_finish = vb2_ops_wait_finish,
>> + .buf_init = video_buf_init,
>> + .buf_prepare = video_buf_prepare,
>> + .buf_queue = video_buf_queue,
>> + .start_streaming = video_start_streaming,
>> + .stop_streaming = video_stop_streaming,
>> +};
>> +
>> +/* -----------------------------------------------------------------------------
>> + * V4L2 ioctls
>> + */
>> +
>> +static int video_querycap(struct file *file, void *fh,
>> + struct v4l2_capability *cap)
>> +{
>> + struct stfcamss_video *video = video_drvdata(file);
>> +
>> + strscpy(cap->driver, "stf camss", sizeof(cap->driver));
>> + strscpy(cap->card, "Starfive Camera Subsystem", sizeof(cap->card));
>> + snprintf(cap->bus_info, sizeof(cap->bus_info), "platform:%s",
>> + dev_name(video->stfcamss->dev));
>
> No need to set bus_info manually, it's done automatically in
> v4l_querycap().
>

Okay, I will drop it.

>> + return 0;
>> +}
>> +
>> +static int video_get_pfmt_by_index(struct stfcamss_video *video, int ndx)
>> +{
>> + int i, j, k;
>> +
>> + /* find index "i" of "k"th unique pixelformat in formats array */
>> + k = -1;
>> + for (i = 0; i < video->nformats; i++) {
>> + for (j = 0; j < i; j++) {
>> + if (video->formats[i].pixelformat ==
>> + video->formats[j].pixelformat)
>> + break;
>> + }
>> +
>> + if (j == i)
>> + k++;
>> +
>> + if (k == ndx)
>> + return i;
>> + }
>> +
>> + return -EINVAL;
>> +}
>> +
>> +static int video_get_pfmt_by_mcode(struct stfcamss_video *video, u32 mcode)
>> +{
>> + int i;
>> +
>> + for (i = 0; i < video->nformats; i++) {
>> + if (video->formats[i].code == mcode)
>> + return i;
>> + }
>> +
>> + return -EINVAL;
>> +}
>> +
>> +static int video_enum_fmt(struct file *file, void *fh, struct v4l2_fmtdesc *f)
>> +{
>> + struct stfcamss_video *video = video_drvdata(file);
>> + int i;
>> +
>> + if (f->type != video->type)
>> + return -EINVAL;
>> + if (f->index >= video->nformats)
>> + return -EINVAL;
>> +
>> + if (f->mbus_code) {
>> + /* Each entry in formats[] table has unique mbus_code */
>> + if (f->index > 0)
>> + return -EINVAL;
>> +
>> + i = video_get_pfmt_by_mcode(video, f->mbus_code);
>> + } else {
>> + i = video_get_pfmt_by_index(video, f->index);
>> + }
>> +
>> + if (i < 0)
>> + return -EINVAL;
>> +
>> + f->pixelformat = video->formats[i].pixelformat;
>> +
>> + return 0;
>> +}
>> +
>> +static int video_enum_framesizes(struct file *file, void *fh,
>> + struct v4l2_frmsizeenum *fsize)
>> +{
>> + struct stfcamss_video *video = video_drvdata(file);
>> + int i;
>> +
>> + if (fsize->index)
>> + return -EINVAL;
>> +
>> + for (i = 0; i < video->nformats; i++) {
>> + if (video->formats[i].pixelformat == fsize->pixel_format)
>> + break;
>> + }
>> +
>> + if (i == video->nformats)
>> + return -EINVAL;
>> +
>> + fsize->type = V4L2_FRMSIZE_TYPE_CONTINUOUS;
>> + fsize->stepwise.min_width = STFCAMSS_FRAME_MIN_WIDTH;
>> + fsize->stepwise.max_width = STFCAMSS_FRAME_MAX_WIDTH;
>> + fsize->stepwise.min_height = STFCAMSS_FRAME_MIN_HEIGHT;
>> + fsize->stepwise.max_height = STFCAMSS_FRAME_MAX_HEIGHT;
>> + fsize->stepwise.step_width = 1;
>> + fsize->stepwise.step_height = 1;
>> +
>> + return 0;
>> +}
>> +
>> +static int video_g_fmt(struct file *file, void *fh, struct v4l2_format *f)
>> +{
>> + struct stfcamss_video *video = video_drvdata(file);
>> +
>> + *f = video->active_fmt;
>> +
>> + return 0;
>> +}
>> +
>> +static int video_s_fmt(struct file *file, void *fh, struct v4l2_format *f)
>> +{
>> + struct stfcamss_video *video = video_drvdata(file);
>> + int ret;
>> +
>> + if (vb2_is_busy(&video->vb2_q))
>> + return -EBUSY;
>> +
>> + ret = __video_try_fmt(video, f);
>> + if (ret < 0)
>> + return ret;
>> +
>> + video->active_fmt = *f;
>> +
>> + return 0;
>> +}
>> +
>> +static int video_try_fmt(struct file *file, void *fh, struct v4l2_format *f)
>> +{
>> + struct stfcamss_video *video = video_drvdata(file);
>> +
>> + return __video_try_fmt(video, f);
>> +}
>> +
>> +static int video_enum_input(struct file *file, void *fh,
>> + struct v4l2_input *input)
>> +{
>> + if (input->index > 0)
>> + return -EINVAL;
>> +
>> + strscpy(input->name, "camera", sizeof(input->name));
>> + input->type = V4L2_INPUT_TYPE_CAMERA;
>> +
>> + return 0;
>> +}
>> +
>> +static int video_g_input(struct file *file, void *fh, unsigned int *input)
>> +{
>> + *input = 0;
>> +
>> + return 0;
>> +}
>> +
>> +static int video_s_input(struct file *file, void *fh, unsigned int input)
>> +{
>> + return input == 0 ? 0 : -EINVAL;
>> +}
>
> You can drop enum_input, g_input and s_input, they make little sense for
> this device.
>

Okay, I will drop them.

>> +
>> +static int video_g_parm(struct file *file, void *priv,
>> + struct v4l2_streamparm *p)
>> +{
>> + struct stfcamss_video *video = video_drvdata(file);
>> + struct video_device *vdev = &video->vdev;
>> + struct media_entity *entity;
>> + struct v4l2_subdev *subdev;
>> + struct media_pad *pad;
>> + int ret, is_support = 0;
>> +
>> + entity = &vdev->entity;
>> + 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_g_parm_cap(vdev, subdev, p);
>
> Unless I'm missing something, the g_parm operation isn't implemented in
> the connected subdev (VIN or ISP), and neither is s_parm. You can just
> drop video_g_parm() and video_s_parm(), you don't have to implement
> them.
>

Okay, I will drop them.

>> + if (ret < 0 && ret != -ENOIOCTLCMD)
>> + break;
>> + if (!ret)
>> + is_support = 1;
>> + }
>> +
>> + return is_support ? 0 : ret;
>> +}
>> +
>> +static int video_s_parm(struct file *file, void *priv,
>> + struct v4l2_streamparm *p)
>> +{
>> + struct stfcamss_video *video = video_drvdata(file);
>> + struct video_device *vdev = &video->vdev;
>> + struct media_entity *entity;
>> + struct v4l2_subdev *subdev;
>> + struct media_pad *pad;
>> + struct v4l2_streamparm tmp_p;
>> + int ret, is_support = 0;
>> +
>> + entity = &vdev->entity;
>> + 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);
>> +
>> + tmp_p = *p;
>> + ret = v4l2_s_parm_cap(vdev, subdev, &tmp_p);
>> + if (ret < 0 && ret != -ENOIOCTLCMD)
>> + break;
>> + if (!ret) {
>> + is_support = 1;
>> + *p = tmp_p;
>> + }
>> + }
>> +
>> + return is_support ? 0 : ret;
>> +}
>> +
>> +static const struct v4l2_ioctl_ops stf_vid_vin_ioctl_ops = {
>> + .vidioc_querycap = video_querycap,
>> + .vidioc_enum_fmt_vid_cap = video_enum_fmt,
>> + .vidioc_enum_fmt_vid_out = video_enum_fmt,
>> + .vidioc_enum_framesizes = video_enum_framesizes,
>> + .vidioc_g_fmt_vid_cap = video_g_fmt,
>> + .vidioc_s_fmt_vid_cap = video_s_fmt,
>> + .vidioc_try_fmt_vid_cap = video_try_fmt,
>> + .vidioc_g_fmt_vid_out = video_g_fmt,
>> + .vidioc_s_fmt_vid_out = video_s_fmt,
>> + .vidioc_try_fmt_vid_out = video_try_fmt,
>> + .vidioc_reqbufs = vb2_ioctl_reqbufs,
>> + .vidioc_querybuf = vb2_ioctl_querybuf,
>> + .vidioc_qbuf = vb2_ioctl_qbuf,
>> + .vidioc_expbuf = vb2_ioctl_expbuf,
>> + .vidioc_dqbuf = vb2_ioctl_dqbuf,
>> + .vidioc_create_bufs = vb2_ioctl_create_bufs,
>> + .vidioc_prepare_buf = vb2_ioctl_prepare_buf,
>> + .vidioc_streamon = vb2_ioctl_streamon,
>> + .vidioc_streamoff = vb2_ioctl_streamoff,
>> + .vidioc_enum_input = video_enum_input,
>> + .vidioc_g_input = video_g_input,
>> + .vidioc_s_input = video_s_input,
>> + .vidioc_g_parm = video_g_parm,
>> + .vidioc_s_parm = video_s_parm,
>> +};
>> +
>> +static const struct v4l2_ioctl_ops stf_vid_isp_ioctl_ops = {
>> + .vidioc_querycap = video_querycap,
>> + .vidioc_enum_fmt_vid_cap = video_enum_fmt,
>> + .vidioc_enum_fmt_vid_out = video_enum_fmt,
>> + .vidioc_enum_framesizes = video_enum_framesizes,
>> + .vidioc_g_fmt_vid_cap = video_g_fmt,
>> + .vidioc_s_fmt_vid_cap = video_s_fmt,
>> + .vidioc_try_fmt_vid_cap = video_try_fmt,
>> + .vidioc_g_fmt_vid_out = video_g_fmt,
>> + .vidioc_s_fmt_vid_out = video_s_fmt,
>> + .vidioc_try_fmt_vid_out = video_try_fmt,
>> + .vidioc_reqbufs = vb2_ioctl_reqbufs,
>> + .vidioc_querybuf = vb2_ioctl_querybuf,
>> + .vidioc_qbuf = vb2_ioctl_qbuf,
>> + .vidioc_expbuf = vb2_ioctl_expbuf,
>> + .vidioc_dqbuf = vb2_ioctl_dqbuf,
>> + .vidioc_create_bufs = vb2_ioctl_create_bufs,
>> + .vidioc_prepare_buf = vb2_ioctl_prepare_buf,
>> + .vidioc_streamon = vb2_ioctl_streamon,
>> + .vidioc_streamoff = vb2_ioctl_streamoff,
>> + .vidioc_enum_input = video_enum_input,
>> + .vidioc_g_input = video_g_input,
>> + .vidioc_s_input = video_s_input,
>> + .vidioc_g_parm = video_g_parm,
>> + .vidioc_s_parm = video_s_parm,
>> +};
>
> Unless I'm mistaken the two structures are identical, you can have a
> single one.
>

Okay, I will use a single structure.

>> +
>> +/* -----------------------------------------------------------------------------
>> + * V4L2 file operations
>> + */
>> +
>> +static int video_open(struct file *file)
>> +{
>> + struct video_device *vdev = video_devdata(file);
>> + struct stfcamss_video *video = video_drvdata(file);
>> + struct v4l2_fh *vfh;
>> + int ret;
>> +
>> + mutex_lock(&video->lock);
>> +
>> + vfh = kzalloc(sizeof(*vfh), GFP_KERNEL);
>> + if (!vfh) {
>> + ret = -ENOMEM;
>> + goto error_alloc;
>> + }
>> +
>> + v4l2_fh_init(vfh, vdev);
>> + v4l2_fh_add(vfh);
>> +
>> + file->private_data = vfh;
>> +
>> + ret = v4l2_pipeline_pm_get(&vdev->entity);
>
> This is a deprecated API, you can drop the call. It will greatly
> simplify video_open(), which can be replaced with v4l2_fh_open(). Same
> for release, you can use v4l2_fh_release().
>
> Regarding power management, you should use runtime PM, calling
> pm_runtime_resume_and_get() when starting streaming (in
> video_start_streaming()) and pm_runtime_put() when stopping streaming.
> As a result of dropping v4l2_pipeline_pm_get() the .s_power() subdev
> operations won't be called automatically. They are deprecated, so they
> should be dropped, and the relevant code moved to the PM runtime
> resume/suspend handlers. You will be able to drop the power_count
> fields.
>

Okay, I will fix it.

>> + if (ret < 0) {
>> + dev_err(video->stfcamss->dev,
>> + "Failed to power up pipeline: %d\n", ret);
>> + goto error_pm_use;
>> + }
>> + mutex_unlock(&video->lock);
>> +
>> + return 0;
>> +
>> +error_pm_use:
>> + v4l2_fh_release(file);
>> +error_alloc:
>> + mutex_unlock(&video->lock);
>> + return ret;
>> +}
>> +
>> +static int video_release(struct file *file)
>> +{
>> + struct video_device *vdev = video_devdata(file);
>> +
>> + vb2_fop_release(file);
>> + v4l2_pipeline_pm_put(&vdev->entity);
>> + file->private_data = NULL;
>> +
>> + return 0;
>> +}
>> +
>> +static const struct v4l2_file_operations stf_vid_fops = {
>> + .owner = THIS_MODULE,
>> + .unlocked_ioctl = video_ioctl2,
>> + .open = video_open,
>> + .release = video_release,
>> + .poll = vb2_fop_poll,
>> + .mmap = vb2_fop_mmap,
>> + .read = vb2_fop_read,
>> +};
>> +
>> +/* -----------------------------------------------------------------------------
>> + * STFCAMSS video core
>> + */
>> +
>> +static void stf_video_release(struct video_device *vdev)
>> +{
>> + struct stfcamss_video *video = video_get_drvdata(vdev);
>> +
>> + media_entity_cleanup(&vdev->entity);
>> +
>> + mutex_destroy(&video->q_lock);
>> + mutex_destroy(&video->lock);
>> +}
>> +
>> +int stf_video_register(struct stfcamss_video *video,
>> + struct v4l2_device *v4l2_dev, const char *name)
>> +{
>> + struct video_device *vdev;
>> + struct vb2_queue *q;
>> + struct media_pad *pad = &video->pad;
>> + int ret;
>> +
>> + vdev = &video->vdev;
>> +
>> + mutex_init(&video->q_lock);
>> +
>> + q = &video->vb2_q;
>> + q->drv_priv = video;
>> + q->mem_ops = &vb2_dma_contig_memops;
>> + q->ops = &stf_video_vb2_q_ops;
>> + q->type = video->type;
>> + q->io_modes = VB2_DMABUF | VB2_MMAP | VB2_READ;
>> + q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
>> + q->buf_struct_size = sizeof(struct stfcamss_buffer);
>> + q->dev = video->stfcamss->dev;
>> + q->lock = &video->q_lock;
>> + q->min_buffers_needed = STFCAMSS_MIN_BUFFERS;
>> + ret = vb2_queue_init(q);
>> + if (ret < 0) {
>> + dev_err(video->stfcamss->dev,
>> + "Failed to init vb2 queue: %d\n", ret);
>> + goto err_vb2_init;
>> + }
>> +
>> + pad->flags = MEDIA_PAD_FL_SINK;
>> + ret = media_entity_pads_init(&vdev->entity, 1, pad);
>> + if (ret < 0) {
>> + dev_err(video->stfcamss->dev,
>> + "Failed to init video entity: %d\n", ret);
>> + goto err_vb2_init;
>> + }
>> +
>> + mutex_init(&video->lock);
>> +
>> + if (video->id == STF_V_LINE_WR) {
>> + video->formats = formats_pix_wr;
>> + video->nformats = ARRAY_SIZE(formats_pix_wr);
>> + video->bpl_alignment = STFCAMSS_FRAME_WIDTH_ALIGN_8;
>> + vdev->ioctl_ops = &stf_vid_vin_ioctl_ops;
>> + } else {
>> + video->formats = formats_pix_isp;
>> + video->nformats = ARRAY_SIZE(formats_pix_isp);
>> + video->bpl_alignment = STFCAMSS_FRAME_WIDTH_ALIGN_8;
>> + vdev->ioctl_ops = &stf_vid_isp_ioctl_ops;
>> + }
>> +
>> + ret = stf_video_init_format(video);
>> + if (ret < 0) {
>> + dev_err(video->stfcamss->dev,
>> + "Failed to init format: %d\n", ret);
>> + goto err_vid_init_format;
>> + }
>> +
>> + vdev->fops = &stf_vid_fops;
>> + vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE;
>> + vdev->vfl_dir = VFL_DIR_RX;
>> + vdev->device_caps |= V4L2_CAP_STREAMING | V4L2_CAP_READWRITE;
>> + vdev->release = stf_video_release;
>> + vdev->v4l2_dev = v4l2_dev;
>> + vdev->queue = &video->vb2_q;
>> + vdev->lock = &video->lock;
>> + strscpy(vdev->name, name, sizeof(vdev->name));
>> +
>> + ret = video_register_device(vdev, VFL_TYPE_VIDEO, video->id);
>> + if (ret < 0) {
>> + dev_err(video->stfcamss->dev,
>> + "Failed to register video device: %d\n", ret);
>> + goto err_vid_reg;
>> + }
>> +
>> + video_set_drvdata(vdev, video);
>> + return 0;
>> +
>> +err_vid_reg:
>> +err_vid_init_format:
>> + media_entity_cleanup(&vdev->entity);
>> + mutex_destroy(&video->lock);
>> +err_vb2_init:
>> + mutex_destroy(&video->q_lock);
>> + return ret;
>> +}
>> +
>> +void stf_video_unregister(struct stfcamss_video *video)
>> +{
>> + vb2_video_unregister_device(&video->vdev);
>> +}
>> diff --git a/drivers/media/platform/starfive/stf_video.h b/drivers/media/platform/starfive/stf_video.h
>> new file mode 100644
>> index 000000000000..63a9a7706a03
>> --- /dev/null
>> +++ b/drivers/media/platform/starfive/stf_video.h
>> @@ -0,0 +1,95 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * stf_video.h
>> + *
>> + * StarFive Camera Subsystem - V4L2 device node
>> + *
>> + * Copyright (C) 2021-2023 StarFive Technology Co., Ltd.
>> + */
>> +
>> +#ifndef STF_VIDEO_H
>> +#define STF_VIDEO_H
>> +
>
> You should include linux/list.h for struct list_head.
>

Okay, I will add it.

>> +#include <linux/mutex.h>
>> +#include <linux/videodev2.h>
>> +#include <media/v4l2-dev.h>
>> +#include <media/v4l2-fh.h>
>> +#include <media/v4l2-ioctl.h>
>> +#include <media/videobuf2-v4l2.h>
>> +
>> +#define STFCAMSS_FRAME_MIN_WIDTH 64
>> +#define STFCAMSS_FRAME_MAX_WIDTH 1920
>> +#define STFCAMSS_FRAME_MIN_HEIGHT 64
>> +#define STFCAMSS_FRAME_MAX_HEIGHT 1080
>> +#define STFCAMSS_FRAME_WIDTH_ALIGN_8 8
>> +#define STFCAMSS_FRAME_WIDTH_ALIGN_128 128
>> +#define STFCAMSS_MIN_BUFFERS 2
>> +
>> +#define STFCAMSS_MAX_ENTITY_NAME_LEN 27
>> +
>> +enum stf_v_line_id {
>> + STF_V_LINE_WR = 0,
>> + STF_V_LINE_ISP,
>> + STF_V_LINE_MAX,
>> +};
>> +
>> +struct stfcamss_buffer {
>> + struct vb2_v4l2_buffer vb;
>> + dma_addr_t addr[3];
>> + struct list_head queue;
>> + int sizeimage;
>
> As far as I can tell, this is set but never used.
>

Yes, I will drop it.

>> +};
>> +
>> +struct fract {
>> + u8 numerator;
>> + u8 denominator;
>> +};
>> +
>> +/*
>> + * struct stfcamss_format_info - ISP media bus format information
>> + * @code: V4L2 media bus format code
>> + * @pixelformat: V4L2 pixel format FCC identifier
>> + * @planes: Number of planes
>> + * @hsub: Horizontal subsampling (for each plane)
>> + * @vsub: Vertical subsampling (for each plane)
>> + * @bpp: Bits per pixel when stored in memory (for each plane)
>> + */
>> +struct stfcamss_format_info {
>> + u32 code;
>> + u32 pixelformat;
>> + u8 planes;
>> + struct fract hsub[3];
>> + struct fract vsub[3];
>
> Only the first element of these arrays is used.
>

Yes, I will fix it.

>> + u8 bpp[3];
>> +};
>> +
>> +struct stfcamss_video {
>> + struct stfcamss *stfcamss;
>> + u8 id;
>> + struct vb2_queue vb2_q;
>> + struct video_device vdev;
>> + struct media_pad pad;
>> + struct media_pipeline pipe;
>
> This isn't used.
>

Okay, I will drop it.

>> + struct v4l2_format active_fmt;
>> + enum v4l2_buf_type type;
>> + const struct stfcamss_video_ops *ops;
>> + struct mutex lock; /* serialize device access */
>> + struct mutex q_lock; /* protects the queue */
>> + unsigned int bpl_alignment;
>> + const struct stfcamss_format_info *formats;
>> + unsigned int nformats;
>> +};
>> +
>> +struct stfcamss_video_ops {
>> + int (*queue_buffer)(struct stfcamss_video *vid,
>> + struct stfcamss_buffer *buf);
>> + int (*flush_buffers)(struct stfcamss_video *vid,
>> + enum vb2_buffer_state state);
>> +};
>> +
>> +int stf_video_register(struct stfcamss_video *video,
>> + struct v4l2_device *v4l2_dev, const char *name);
>> +
>> +void stf_video_unregister(struct stfcamss_video *video);
>> +
>> +#endif /* STF_VIDEO_H */
>