[PATCH 01/16] media: sun6i-csi: bridge: Use V4L2 subdev active state

arash golgol arash.golgol at gmail.com
Thu Jul 2 00:38:23 PDT 2026


Hi Paul,

On Mon, May 18, 2026 at 1:55 PM Paul Kocialkowski <paulk at sys-base.io> wrote:
>
> From: Arash Golgol <arash.golgol at gmail.com>
>
> Use the V4L2 subdev active state API to store the active format.
> This simplifies the driver not only by dropping the bridge mbus_format
> field, but it also allows dropping the bridge lock, replaced with
> the state lock.
>
> Previously, capture accessed bridge private state directly. After
> moving to framework-managed state, resolve the format through the
> subdev pad API.
>
> The sun6i-csi-bridge hardware does not perform any format conversion.
> Enforce identical formats on the sink and source pads in the set_fmt()
> and init_state() callbacks.
>
> Signed-off-by: Arash Golgol <arash.golgol at gmail.com>
> Reviewed-by: Paul Kocialkowski <paulk at sys-base.io>
> Tested-by: Paul Kocialkowski <paulk at sys-base.io>
> Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

I noticed this series didn't make it into the v7.2 merge window.
Is there anything still pending on my side before it can be picked up,
or is it just a matter of timing for the next cycle?

Happy to help however I can.

> ---
>  .../sunxi/sun6i-csi/sun6i_csi_bridge.c        | 155 ++++++++----------
>  .../sunxi/sun6i-csi/sun6i_csi_bridge.h        |   9 -
>  .../sunxi/sun6i-csi/sun6i_csi_capture.c       |  27 ++-
>  3 files changed, 86 insertions(+), 105 deletions(-)
>
> diff --git a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_bridge.c b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_bridge.c
> index d006d9dd0170..43a85bcc2ba2 100644
> --- a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_bridge.c
> +++ b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_bridge.c
> @@ -13,26 +13,6 @@
>  #include "sun6i_csi_bridge.h"
>  #include "sun6i_csi_reg.h"
>
> -/* Helpers */
> -
> -void sun6i_csi_bridge_dimensions(struct sun6i_csi_device *csi_dev,
> -                                unsigned int *width, unsigned int *height)
> -{
> -       if (width)
> -               *width = csi_dev->bridge.mbus_format.width;
> -       if (height)
> -               *height = csi_dev->bridge.mbus_format.height;
> -}
> -
> -void sun6i_csi_bridge_format(struct sun6i_csi_device *csi_dev,
> -                            u32 *mbus_code, u32 *field)
> -{
> -       if (mbus_code)
> -               *mbus_code = csi_dev->bridge.mbus_format.code;
> -       if (field)
> -               *field = csi_dev->bridge.mbus_format.field;
> -}
> -
>  /* Format */
>
>  static const struct sun6i_csi_bridge_format sun6i_csi_bridge_formats[] = {
> @@ -226,7 +206,8 @@ static void sun6i_csi_bridge_disable(struct sun6i_csi_device *csi_dev)
>  }
>
>  static void
> -sun6i_csi_bridge_configure_parallel(struct sun6i_csi_device *csi_dev)
> +sun6i_csi_bridge_configure_parallel(struct sun6i_csi_device *csi_dev,
> +                                   const struct v4l2_mbus_framefmt *mbus_format)
>  {
>         struct device *dev = csi_dev->dev;
>         struct regmap *regmap = csi_dev->regmap;
> @@ -234,11 +215,9 @@ sun6i_csi_bridge_configure_parallel(struct sun6i_csi_device *csi_dev)
>                 &csi_dev->bridge.source_parallel.endpoint;
>         unsigned char bus_width = endpoint->bus.parallel.bus_width;
>         unsigned int flags = endpoint->bus.parallel.flags;
> -       u32 field;
> +       u32 field = mbus_format->field;
>         u32 value = SUN6I_CSI_IF_CFG_IF_CSI;
>
> -       sun6i_csi_bridge_format(csi_dev, NULL, &field);
> -
>         if (field == V4L2_FIELD_INTERLACED ||
>             field == V4L2_FIELD_INTERLACED_TB ||
>             field == V4L2_FIELD_INTERLACED_BT)
> @@ -317,13 +296,12 @@ sun6i_csi_bridge_configure_parallel(struct sun6i_csi_device *csi_dev)
>  }
>
>  static void
> -sun6i_csi_bridge_configure_mipi_csi2(struct sun6i_csi_device *csi_dev)
> +sun6i_csi_bridge_configure_mipi_csi2(struct sun6i_csi_device *csi_dev,
> +                                    const struct v4l2_mbus_framefmt *mbus_format)
>  {
>         struct regmap *regmap = csi_dev->regmap;
>         u32 value = SUN6I_CSI_IF_CFG_IF_MIPI;
> -       u32 field;
> -
> -       sun6i_csi_bridge_format(csi_dev, NULL, &field);
> +       u32 field = mbus_format->field;
>
>         if (field == V4L2_FIELD_INTERLACED ||
>             field == V4L2_FIELD_INTERLACED_TB ||
> @@ -335,19 +313,20 @@ sun6i_csi_bridge_configure_mipi_csi2(struct sun6i_csi_device *csi_dev)
>         regmap_write(regmap, SUN6I_CSI_IF_CFG_REG, value);
>  }
>
> -static void sun6i_csi_bridge_configure_format(struct sun6i_csi_device *csi_dev)
> +static void
> +sun6i_csi_bridge_configure_format(struct sun6i_csi_device *csi_dev,
> +                                 const struct v4l2_mbus_framefmt *mbus_format)
>  {
>         struct regmap *regmap = csi_dev->regmap;
>         bool capture_streaming = csi_dev->capture.state.streaming;
>         const struct sun6i_csi_bridge_format *bridge_format;
>         const struct sun6i_csi_capture_format *capture_format;
> -       u32 mbus_code, field, pixelformat;
> +       u32 pixelformat;
> +       u32 field = mbus_format->field;
>         u8 input_format, input_yuv_seq, output_format;
>         u32 value = 0;
>
> -       sun6i_csi_bridge_format(csi_dev, &mbus_code, &field);
> -
> -       bridge_format = sun6i_csi_bridge_format_find(mbus_code);
> +       bridge_format = sun6i_csi_bridge_format_find(mbus_format->code);
>         if (WARN_ON(!bridge_format))
>                 return;
>
> @@ -391,16 +370,17 @@ static void sun6i_csi_bridge_configure_format(struct sun6i_csi_device *csi_dev)
>  }
>
>  static void sun6i_csi_bridge_configure(struct sun6i_csi_device *csi_dev,
> -                                      struct sun6i_csi_bridge_source *source)
> +                                      struct sun6i_csi_bridge_source *source,
> +                                      const struct v4l2_mbus_framefmt *mbus_format)
>  {
>         struct sun6i_csi_bridge *bridge = &csi_dev->bridge;
>
>         if (source == &bridge->source_parallel)
> -               sun6i_csi_bridge_configure_parallel(csi_dev);
> +               sun6i_csi_bridge_configure_parallel(csi_dev, mbus_format);
>         else
> -               sun6i_csi_bridge_configure_mipi_csi2(csi_dev);
> +               sun6i_csi_bridge_configure_mipi_csi2(csi_dev, mbus_format);
>
> -       sun6i_csi_bridge_configure_format(csi_dev);
> +       sun6i_csi_bridge_configure_format(csi_dev, mbus_format);
>  }
>
>  /* V4L2 Subdev */
> @@ -415,6 +395,8 @@ static int sun6i_csi_bridge_s_stream(struct v4l2_subdev *subdev, int on)
>         struct sun6i_csi_bridge_source *source;
>         struct v4l2_subdev *source_subdev;
>         struct media_pad *remote_pad;
> +       struct v4l2_subdev_state *state;
> +       const struct v4l2_mbus_framefmt *mbus_format;
>         int ret;
>
>         /* Source */
> @@ -433,6 +415,10 @@ static int sun6i_csi_bridge_s_stream(struct v4l2_subdev *subdev, int on)
>         else
>                 source = &bridge->source_mipi_csi2;
>
> +       /* Active State */
> +
> +       state = v4l2_subdev_lock_and_get_active_state(subdev);
> +
>         if (!on) {
>                 v4l2_subdev_call(source_subdev, video, s_stream, 0);
>                 ret = 0;
> @@ -443,7 +429,7 @@ static int sun6i_csi_bridge_s_stream(struct v4l2_subdev *subdev, int on)
>
>         ret = pm_runtime_resume_and_get(dev);
>         if (ret < 0)
> -               return ret;
> +               goto unlock;
>
>         /* Clear */
>
> @@ -451,7 +437,9 @@ static int sun6i_csi_bridge_s_stream(struct v4l2_subdev *subdev, int on)
>
>         /* Configure */
>
> -       sun6i_csi_bridge_configure(csi_dev, source);
> +       mbus_format = v4l2_subdev_state_get_format(state,
> +                                                  SUN6I_CSI_BRIDGE_PAD_SINK);
> +       sun6i_csi_bridge_configure(csi_dev, source, mbus_format);
>
>         if (capture_streaming)
>                 sun6i_csi_capture_configure(csi_dev);
> @@ -472,7 +460,8 @@ static int sun6i_csi_bridge_s_stream(struct v4l2_subdev *subdev, int on)
>         if (ret && ret != -ENOIOCTLCMD)
>                 goto disable;
>
> -       return 0;
> +       ret = 0;
> +       goto unlock;
>
>  disable:
>         if (capture_streaming)
> @@ -482,6 +471,8 @@ static int sun6i_csi_bridge_s_stream(struct v4l2_subdev *subdev, int on)
>
>         pm_runtime_put(dev);
>
> +unlock:
> +       v4l2_subdev_unlock_state(state);
>         return ret;
>  }
>
> @@ -504,21 +495,23 @@ sun6i_csi_bridge_mbus_format_prepare(struct v4l2_mbus_framefmt *mbus_format)
>  static int sun6i_csi_bridge_init_state(struct v4l2_subdev *subdev,
>                                        struct v4l2_subdev_state *state)
>  {
> -       struct sun6i_csi_device *csi_dev = v4l2_get_subdevdata(subdev);
> -       unsigned int pad = SUN6I_CSI_BRIDGE_PAD_SINK;
> -       struct v4l2_mbus_framefmt *mbus_format =
> -               v4l2_subdev_state_get_format(state, pad);
> -       struct mutex *lock = &csi_dev->bridge.lock;
> +       unsigned int pad;
>
> -       mutex_lock(lock);
> +       /*
> +        * This subdev does not perform format conversion,
> +        * initialize both pads identically.
> +        */
> +       for (pad = 0; pad < subdev->entity.num_pads; pad++) {
> +               struct v4l2_mbus_framefmt *mbus_format;
>
> -       mbus_format->code = sun6i_csi_bridge_formats[0].mbus_code;
> -       mbus_format->width = 1280;
> -       mbus_format->height = 720;
> +               mbus_format = v4l2_subdev_state_get_format(state, pad);
>
> -       sun6i_csi_bridge_mbus_format_prepare(mbus_format);
> +               mbus_format->code = sun6i_csi_bridge_formats[0].mbus_code;
> +               mbus_format->width = 1280;
> +               mbus_format->height = 720;
>
> -       mutex_unlock(lock);
> +               sun6i_csi_bridge_mbus_format_prepare(mbus_format);
> +       }
>
>         return 0;
>  }
> @@ -536,53 +529,32 @@ sun6i_csi_bridge_enum_mbus_code(struct v4l2_subdev *subdev,
>         return 0;
>  }
>
> -static int sun6i_csi_bridge_get_fmt(struct v4l2_subdev *subdev,
> -                                   struct v4l2_subdev_state *state,
> -                                   struct v4l2_subdev_format *format)
> -{
> -       struct sun6i_csi_device *csi_dev = v4l2_get_subdevdata(subdev);
> -       struct v4l2_mbus_framefmt *mbus_format = &format->format;
> -       struct mutex *lock = &csi_dev->bridge.lock;
> -
> -       mutex_lock(lock);
> -
> -       if (format->which == V4L2_SUBDEV_FORMAT_TRY)
> -               *mbus_format = *v4l2_subdev_state_get_format(state,
> -                                                            format->pad);
> -       else
> -               *mbus_format = csi_dev->bridge.mbus_format;
> -
> -       mutex_unlock(lock);
> -
> -       return 0;
> -}
> -
>  static int sun6i_csi_bridge_set_fmt(struct v4l2_subdev *subdev,
>                                     struct v4l2_subdev_state *state,
>                                     struct v4l2_subdev_format *format)
>  {
> -       struct sun6i_csi_device *csi_dev = v4l2_get_subdevdata(subdev);
> -       struct v4l2_mbus_framefmt *mbus_format = &format->format;
> -       struct mutex *lock = &csi_dev->bridge.lock;
> +       struct v4l2_mbus_framefmt *fmt;
>
> -       mutex_lock(lock);
> +       /* The format on the source pad always matches the sink pad. */
> +       if (format->pad != SUN6I_CSI_BRIDGE_PAD_SINK)
> +               return v4l2_subdev_get_fmt(subdev, state, format);
>
> -       sun6i_csi_bridge_mbus_format_prepare(mbus_format);
> +       sun6i_csi_bridge_mbus_format_prepare(&format->format);
>
> -       if (format->which == V4L2_SUBDEV_FORMAT_TRY)
> -               *v4l2_subdev_state_get_format(state, format->pad) =
> -                       *mbus_format;
> -       else
> -               csi_dev->bridge.mbus_format = *mbus_format;
> +       /* Set the format on the sink pad. */
> +       fmt = v4l2_subdev_state_get_format(state, format->pad);
> +       *fmt = format->format;
>
> -       mutex_unlock(lock);
> +       /* Propagate the format to the source pad. */
> +       fmt = v4l2_subdev_state_get_format(state, SUN6I_CSI_BRIDGE_PAD_SOURCE);
> +       *fmt = format->format;
>
>         return 0;
>  }
>
>  static const struct v4l2_subdev_pad_ops sun6i_csi_bridge_pad_ops = {
>         .enum_mbus_code = sun6i_csi_bridge_enum_mbus_code,
> -       .get_fmt        = sun6i_csi_bridge_get_fmt,
> +       .get_fmt        = v4l2_subdev_get_fmt,
>         .set_fmt        = sun6i_csi_bridge_set_fmt,
>  };
>
> @@ -780,8 +752,6 @@ int sun6i_csi_bridge_setup(struct sun6i_csi_device *csi_dev)
>         };
>         int ret;
>
> -       mutex_init(&bridge->lock);
> -
>         /* V4L2 Subdev */
>
>         v4l2_subdev_init(subdev, &sun6i_csi_bridge_subdev_ops);
> @@ -809,6 +779,12 @@ int sun6i_csi_bridge_setup(struct sun6i_csi_device *csi_dev)
>         if (ret < 0)
>                 return ret;
>
> +       /* V4L2 Subdev finalize */
> +
> +       ret = v4l2_subdev_init_finalize(subdev);
> +       if (ret < 0)
> +               goto error_media_entity;
> +
>         /* V4L2 Subdev */
>
>         if (csi_dev->isp_available)
> @@ -818,7 +794,7 @@ int sun6i_csi_bridge_setup(struct sun6i_csi_device *csi_dev)
>
>         if (ret) {
>                 dev_err(dev, "failed to register v4l2 subdev: %d\n", ret);
> -               goto error_media_entity;
> +               goto error_subdev_finalize;
>         }
>
>         /* V4L2 Async */
> @@ -852,6 +828,9 @@ int sun6i_csi_bridge_setup(struct sun6i_csi_device *csi_dev)
>         else
>                 v4l2_device_unregister_subdev(subdev);
>
> +error_subdev_finalize:
> +       v4l2_subdev_cleanup(subdev);
> +
>  error_media_entity:
>         media_entity_cleanup(&subdev->entity);
>
> @@ -868,5 +847,7 @@ void sun6i_csi_bridge_cleanup(struct sun6i_csi_device *csi_dev)
>
>         v4l2_device_unregister_subdev(subdev);
>
> +       v4l2_subdev_cleanup(subdev);
> +
>         media_entity_cleanup(&subdev->entity);
>  }
> diff --git a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_bridge.h b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_bridge.h
> index 44653b38f722..a5b0a6f064dd 100644
> --- a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_bridge.h
> +++ b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_bridge.h
> @@ -42,20 +42,11 @@ struct sun6i_csi_bridge {
>         struct v4l2_subdev              subdev;
>         struct v4l2_async_notifier      notifier;
>         struct media_pad                pads[2];
> -       struct v4l2_mbus_framefmt       mbus_format;
> -       struct mutex                    lock; /* Mbus format lock. */
>
>         struct sun6i_csi_bridge_source  source_parallel;
>         struct sun6i_csi_bridge_source  source_mipi_csi2;
>  };
>
> -/* Helpers */
> -
> -void sun6i_csi_bridge_dimensions(struct sun6i_csi_device *csi_dev,
> -                                unsigned int *width, unsigned int *height);
> -void sun6i_csi_bridge_format(struct sun6i_csi_device *csi_dev,
> -                            u32 *mbus_code, u32 *field);
> -
>  /* Format */
>
>  const struct sun6i_csi_bridge_format *
> diff --git a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_capture.c b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_capture.c
> index 65879f4802c0..d90abba21309 100644
> --- a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_capture.c
> +++ b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_capture.c
> @@ -888,14 +888,19 @@ static int sun6i_csi_capture_link_validate(struct media_link *link)
>                 media_entity_to_video_device(link->sink->entity);
>         struct sun6i_csi_device *csi_dev = video_get_drvdata(video_dev);
>         struct v4l2_device *v4l2_dev = csi_dev->v4l2_dev;
> +       struct v4l2_subdev *src_subdev =
> +               media_entity_to_v4l2_subdev(link->source->entity);
>         const struct sun6i_csi_capture_format *capture_format;
>         const struct sun6i_csi_bridge_format *bridge_format;
>         unsigned int capture_width, capture_height;
> -       unsigned int bridge_width, bridge_height;
>         const struct v4l2_format_info *format_info;
> +       struct v4l2_subdev_format src_fmt = {
> +               .which = V4L2_SUBDEV_FORMAT_ACTIVE,
> +               .pad = link->source->index
> +       };
>         u32 pixelformat, capture_field;
> -       u32 mbus_code, bridge_field;
>         bool match;
> +       int ret;
>
>         sun6i_csi_capture_dimensions(csi_dev, &capture_width, &capture_height);
>
> @@ -904,19 +909,22 @@ static int sun6i_csi_capture_link_validate(struct media_link *link)
>         if (WARN_ON(!capture_format))
>                 return -EINVAL;
>
> -       sun6i_csi_bridge_dimensions(csi_dev, &bridge_width, &bridge_height);
> +       /* Resolve csi bridge format. */
> +       ret = v4l2_subdev_call(src_subdev, pad, get_fmt, NULL, &src_fmt);
> +       if (ret)
> +               return ret;
>
> -       sun6i_csi_bridge_format(csi_dev, &mbus_code, &bridge_field);
> -       bridge_format = sun6i_csi_bridge_format_find(mbus_code);
> +       bridge_format = sun6i_csi_bridge_format_find(src_fmt.format.code);
>         if (WARN_ON(!bridge_format))
>                 return -EINVAL;
>
>         /* No cropping/scaling is supported. */
> -       if (capture_width != bridge_width || capture_height != bridge_height) {
> +       if (capture_width != src_fmt.format.width ||
> +           capture_height != src_fmt.format.height) {
>                 v4l2_err(v4l2_dev,
>                          "invalid input/output dimensions: %ux%u/%ux%u\n",
> -                        bridge_width, bridge_height, capture_width,
> -                        capture_height);
> +                        src_fmt.format.width, src_fmt.format.height,
> +                        capture_width, capture_height);
>                 return -EINVAL;
>         }
>
> @@ -947,7 +955,8 @@ static int sun6i_csi_capture_link_validate(struct media_link *link)
>         /* With raw input mode, we need a 1:1 match between input and output. */
>         if (bridge_format->input_format == SUN6I_CSI_INPUT_FMT_RAW ||
>             capture_format->input_format_raw) {
> -               match = sun6i_csi_capture_format_match(pixelformat, mbus_code);
> +               match = sun6i_csi_capture_format_match(pixelformat,
> +                                                      src_fmt.format.code);
>                 if (!match)
>                         goto invalid;
>         }
> --
> 2.54.0
>

-- 
Regards,
Arash Golgol



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