Hi Dan,
Thank you for the patch.
On Mon, Dec 19, 2022 at 02:43:15PM +0000, Daniel Scally wrote:
> In preparation for allowing more than the default color matching
> descriptor, make the color matching attributes writeable.
>
> Signed-off-by: Daniel Scally <dan.scally@xxxxxxxxxxxxxxxx>
> ---
> Changes in v2:
>
> - Check refcnt before allowing the change in .store()
> - Renamed uvcg_cmd to uvcg_color_matching
>
> .../ABI/testing/configfs-usb-gadget-uvc | 2 +-
> drivers/usb/gadget/function/uvc_configfs.c | 36 ++++++++++++++++++-
> 2 files changed, 36 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/ABI/testing/configfs-usb-gadget-uvc b/Documentation/ABI/testing/configfs-usb-gadget-uvc
> index f00cff6d8c5c..53258b7c6f2d 100644
> --- a/Documentation/ABI/testing/configfs-usb-gadget-uvc
> +++ b/Documentation/ABI/testing/configfs-usb-gadget-uvc
> @@ -165,7 +165,7 @@ Date: Dec 2014
> KernelVersion: 4.0
> Description: Default color matching descriptors
>
> - All attributes read only:
> + All attributes read/write:
>
> ======================== ======================================
> bMatrixCoefficients matrix used to compute luma and
> diff --git a/drivers/usb/gadget/function/uvc_configfs.c b/drivers/usb/gadget/function/uvc_configfs.c
> index 6fb7ac8366fe..ef5d75942f24 100644
> --- a/drivers/usb/gadget/function/uvc_configfs.c
> +++ b/drivers/usb/gadget/function/uvc_configfs.c
> @@ -1851,7 +1851,41 @@ static ssize_t uvcg_color_matching_##cname##_show( \
> return result; \
> } \
> \
> -UVC_ATTR_RO(uvcg_color_matching_, cname, aname)
> +static ssize_t uvcg_color_matching_##cname##_store( \
> + struct config_item *item, const char *page, size_t len) \
> +{ \
> + struct config_group *group = to_config_group(item); \
> + struct mutex *su_mutex = &group->cg_subsys->su_mutex; \
> + struct uvcg_color_matching *color_match = \
> + to_uvcg_color_matching(group); \
> + struct f_uvc_opts *opts; \
> + struct config_item *opts_item; \
> + int ret; \
> + u##bits num; \
> + \
> + if (color_match->refcnt) \
Shouldn't this be protected by the same lock that you use to modify
refcnt in 7/7 ?
> + return -EBUSY; \
> + \
> + ret = kstrtou##bits(page, 0, &num); \
> + if (ret) \
> + return ret; \
> + \
> + mutex_lock(su_mutex); /* for navigating configfs hierarchy */ \
> + \
> + opts_item = group->cg_item.ci_parent->ci_parent->ci_parent; \
> + opts = to_f_uvc_opts(opts_item); \
> + \
> + mutex_lock(&opts->lock); \
> + \
> + color_match->desc.aname = num; \
> + ret = len; \
> + \
> + mutex_unlock(&opts->lock); \
> + mutex_unlock(su_mutex); \
> + \
> + return ret; \
> +} \
> +UVC_ATTR(uvcg_color_matching_, cname, aname)
>
> UVCG_COLOR_MATCHING_ATTR(b_color_primaries, bColorPrimaries, 8);
> UVCG_COLOR_MATCHING_ATTR(b_transfer_characteristics, bTransferCharacteristics, 8);
--
Regards,
Laurent Pinchart
