Hi Sam,
Thank you for the patch.
On Mon, Dec 02, 2019 at 08:32:05PM +0100, Sam Ravnborg wrote:
> The callbacks in drm_panel_funcs are optional, so do not
> return an error just because no callback is assigned.
Unless I'm mistaken the callbacks are not documented as optional. Should
this be fixed too ?
> Signed-off-by: Sam Ravnborg <sam@xxxxxxxxxxxx>
> Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
> Cc: Maxime Ripard <mripard@xxxxxxxxxx>
> Cc: Thierry Reding <thierry.reding@xxxxxxxxx>
> Cc: Sam Ravnborg <sam@xxxxxxxxxxxx>
> Cc: David Airlie <airlied@xxxxxxxx>
> Cc: Daniel Vetter <daniel@xxxxxxxx>
> ---
> drivers/gpu/drm/drm_panel.c | 35 +++++++++++++++++++++++++----------
> 1 file changed, 25 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
> index ed7985c0535a..2d59cdd05e50 100644
> --- a/drivers/gpu/drm/drm_panel.c
> +++ b/drivers/gpu/drm/drm_panel.c
> @@ -151,10 +151,13 @@ EXPORT_SYMBOL(drm_panel_detach);
> */
> int drm_panel_prepare(struct drm_panel *panel)
> {
> - if (panel && panel->funcs && panel->funcs->prepare)
> + if (!panel)
> + return -EINVAL;
> +
> + if (panel->funcs && panel->funcs->prepare)
> return panel->funcs->prepare(panel);
>
> - return panel ? -ENOSYS : -EINVAL;
> + return 0;
> }
> EXPORT_SYMBOL(drm_panel_prepare);
>
> @@ -171,10 +174,13 @@ EXPORT_SYMBOL(drm_panel_prepare);
> */
> int drm_panel_unprepare(struct drm_panel *panel)
> {
> - if (panel && panel->funcs && panel->funcs->unprepare)
> + if (!panel)
> + return -EINVAL;
> +
> + if (panel->funcs && panel->funcs->unprepare)
> return panel->funcs->unprepare(panel);
>
> - return panel ? -ENOSYS : -EINVAL;
> + return 0;
> }
> EXPORT_SYMBOL(drm_panel_unprepare);
>
> @@ -190,10 +196,13 @@ EXPORT_SYMBOL(drm_panel_unprepare);
> */
> int drm_panel_enable(struct drm_panel *panel)
> {
> - if (panel && panel->funcs && panel->funcs->enable)
> + if (!panel)
> + return -EINVAL;
> +
> + if (panel->funcs && panel->funcs->enable)
> return panel->funcs->enable(panel);
>
> - return panel ? -ENOSYS : -EINVAL;
> + return 0;
> }
> EXPORT_SYMBOL(drm_panel_enable);
>
> @@ -209,10 +218,13 @@ EXPORT_SYMBOL(drm_panel_enable);
> */
> int drm_panel_disable(struct drm_panel *panel)
> {
> - if (panel && panel->funcs && panel->funcs->disable)
> + if (!panel)
> + return -EINVAL;
> +
> + if (panel->funcs && panel->funcs->disable)
> return panel->funcs->disable(panel);
>
> - return panel ? -ENOSYS : -EINVAL;
> + return 0;
> }
> EXPORT_SYMBOL(drm_panel_disable);
>
> @@ -228,10 +240,13 @@ EXPORT_SYMBOL(drm_panel_disable);
> */
> int drm_panel_get_modes(struct drm_panel *panel)
> {
> - if (panel && panel->funcs && panel->funcs->get_modes)
> + if (!panel)
> + return -EINVAL;
> +
> + if (panel->funcs && panel->funcs->get_modes)
> return panel->funcs->get_modes(panel);
Should get_modes() be optional ? As far as I can tell all the panel
drivers in drivers/gpu/drm/panel/ implement it, and I'm not sure to see
how a panel could be usable if it can't return its mode.
On the other hand you return 0 if the callback isn't implemented, which
doesn't mean success here, so I suppose that's fine, but I don't think
we should document .get_modes() as being optional.
With these issues addressed (if they need to be),
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
>
> - return panel ? -ENOSYS : -EINVAL;
> + return 0;
> }
> EXPORT_SYMBOL(drm_panel_get_modes);
>
--
Regards,
Laurent Pinchart
