Hi Marek,
CC'ing Tomi to get his opinion.
On Sun, Jun 19, 2022 at 12:24:42AM +0200, Marek Vasut wrote:
> Any local subdev state should be allocated and free'd using
> __v4l2_subdev_state_alloc()/__v4l2_subdev_state_free(), which
> takes care of calling .init_cfg() subdev op. Without this,
> subdev internal state might be uninitialized by the time
> any other subdev op is called.
>
> Signed-off-by: Marek Vasut <marex@xxxxxxx>
> Cc: Alain Volmat <alain.volmat@xxxxxxxxxxx>
> Cc: Alexandre Torgue <alexandre.torgue@xxxxxxxxxxx>
> Cc: Amelie DELAUNAY <amelie.delaunay@xxxxxxxxxxx>
> Cc: Hugues FRUCHET <hugues.fruchet@xxxxxxxxxxx>
> Cc: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> Cc: Philippe CORNU <philippe.cornu@xxxxxxxxxxx>
> Cc: linux-stm32@xxxxxxxxxxxxxxxxxxxxxxxxxxxx
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> ---
> drivers/media/platform/st/stm32/stm32-dcmi.c | 51 +++++++++++---------
> 1 file changed, 29 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/media/platform/st/stm32/stm32-dcmi.c b/drivers/media/platform/st/stm32/stm32-dcmi.c
> index ec54b5ecfd544..ef795c12fb233 100644
> --- a/drivers/media/platform/st/stm32/stm32-dcmi.c
> +++ b/drivers/media/platform/st/stm32/stm32-dcmi.c
> @@ -996,22 +996,26 @@ static int dcmi_try_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f,
> struct dcmi_framesize *sd_framesize)
> {
> const struct dcmi_format *sd_fmt;
> + static struct lock_class_key key;
> struct dcmi_framesize sd_fsize;
> struct v4l2_pix_format *pix = &f->fmt.pix;
> - struct v4l2_subdev_pad_config pad_cfg;
> - struct v4l2_subdev_state pad_state = {
> - .pads = &pad_cfg
> - };
> + struct v4l2_subdev_state *sd_state;
> struct v4l2_subdev_format format = {
> .which = V4L2_SUBDEV_FORMAT_TRY,
> };
> bool do_crop;
> int ret;
>
> + sd_state = __v4l2_subdev_state_alloc(dcmi->source, "dcmi:state->lock", &key);
> + if (IS_ERR(sd_state))
> + return PTR_ERR(sd_state);
> +
> sd_fmt = find_format_by_fourcc(dcmi, pix->pixelformat);
> if (!sd_fmt) {
> - if (!dcmi->num_of_sd_formats)
> - return -ENODATA;
> + if (!dcmi->num_of_sd_formats) {
> + ret = -ENODATA;
> + goto done;
> + }
>
> sd_fmt = dcmi->sd_formats[dcmi->num_of_sd_formats - 1];
> pix->pixelformat = sd_fmt->fourcc;
> @@ -1036,10 +1040,9 @@ static int dcmi_try_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f,
> }
>
> v4l2_fill_mbus_format(&format.format, pix, sd_fmt->mbus_code);
> - ret = v4l2_subdev_call(dcmi->source, pad, set_fmt,
> - &pad_state, &format);
> + ret = v4l2_subdev_call(dcmi->source, pad, set_fmt, sd_state, &format);
> if (ret < 0)
> - return ret;
> + goto done;
>
> /* Update pix regarding to what sensor can do */
> v4l2_fill_pix_format(pix, &format.format);
> @@ -1079,7 +1082,9 @@ static int dcmi_try_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f,
> if (sd_framesize)
> *sd_framesize = sd_fsize;
>
> - return 0;
> +done:
> + __v4l2_subdev_state_free(sd_state);
> + return ret;
> }
>
> static int dcmi_set_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f)
> @@ -1183,31 +1188,33 @@ static int dcmi_set_sensor_format(struct stm32_dcmi *dcmi,
> struct v4l2_pix_format *pix)
> {
> const struct dcmi_format *sd_fmt;
> + static struct lock_class_key key;
> + struct v4l2_subdev_state *sd_state;
> struct v4l2_subdev_format format = {
> .which = V4L2_SUBDEV_FORMAT_TRY,
> };
> - struct v4l2_subdev_pad_config pad_cfg;
> - struct v4l2_subdev_state pad_state = {
> - .pads = &pad_cfg
> - };
> int ret;
>
> + sd_state = __v4l2_subdev_state_alloc(dcmi->source, "dcmi:state->lock", &key);
> + if (IS_ERR(sd_state))
> + return PTR_ERR(sd_state);
> +
> sd_fmt = find_format_by_fourcc(dcmi, pix->pixelformat);
> if (!sd_fmt) {
> - if (!dcmi->num_of_sd_formats)
> - return -ENODATA;
> + if (!dcmi->num_of_sd_formats) {
> + ret = -ENODATA;
> + goto done;
> + }
>
> sd_fmt = dcmi->sd_formats[dcmi->num_of_sd_formats - 1];
> pix->pixelformat = sd_fmt->fourcc;
> }
>
> v4l2_fill_mbus_format(&format.format, pix, sd_fmt->mbus_code);
> - ret = v4l2_subdev_call(dcmi->source, pad, set_fmt,
> - &pad_state, &format);
> - if (ret < 0)
> - return ret;
> -
> - return 0;
> + ret = v4l2_subdev_call(dcmi->source, pad, set_fmt, sd_state, &format);
> +done:
> + __v4l2_subdev_state_free(sd_state);
> + return ret;
> }
>
> static int dcmi_get_sensor_bounds(struct stm32_dcmi *dcmi,
--
Regards,
Laurent Pinchart
