Hi Hsin-Yi,
On Mon, Jun 06, 2022 at 11:24:24PM +0800, Hsin-Yi Wang wrote:
> Panels usually call drm_connector_set_panel_orientation(), which is
> later than drm/kms driver calling drm_dev_register(). This leads to a
> WARN().
>
> The orientation property is known earlier. For example, some panels
> parse the property through device tree during probe.
>
> Add an API to return the property from panel to drm/kms driver, so the
> drivers are able to call drm_connector_set_panel_orientation() before
> drm_dev_register().
>
> Suggested-by: Hans de Goede <hdego...@redhat.com>
> Signed-off-by: Hsin-Yi Wang <hsi...@chromium.org>
> Reviewed-by: Hans de Goede <hdego...@redhat.com>
> Reviewed-by: Douglas Anderson <diand...@chromium.org>
> ---
> v3->v4: Add a blank line.
> ---
> drivers/gpu/drm/drm_panel.c | 9 +++++++++
> include/drm/drm_panel.h | 10 ++++++++++
> 2 files changed, 19 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
> index f634371c717a..e12056cfeca8 100644
> --- a/drivers/gpu/drm/drm_panel.c
> +++ b/drivers/gpu/drm/drm_panel.c
> @@ -223,6 +223,15 @@ int drm_panel_get_modes(struct drm_panel *panel,
> }
> EXPORT_SYMBOL(drm_panel_get_modes);
>
> +enum drm_panel_orientation drm_panel_get_orientation(struct drm_panel *panel)
const as mentioned by Stephen.
> +{
> + if (panel && panel->funcs && panel->funcs->get_orientation)
> + return panel->funcs->get_orientation(panel);
> +
> + return DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
> +}
> +EXPORT_SYMBOL(drm_panel_get_orientation);
> +
> #ifdef CONFIG_OF
> /**
> * of_drm_find_panel - look up a panel using a device tree node
> diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
> index d279ee455f01..5dadbf3b0370 100644
> --- a/include/drm/drm_panel.h
> +++ b/include/drm/drm_panel.h
> @@ -133,6 +133,15 @@ struct drm_panel_funcs {
> * Allows panels to create panels-specific debugfs files.
> */
> void (*debugfs_init)(struct drm_panel *panel, struct dentry *root);
> +
> + /**
> + * @get_orientation:
> + *
> + * Return the panel orientation set by device tree or EDID.
> + *
> + * This function is optional.
> + */
> + enum drm_panel_orientation (*get_orientation)(struct drm_panel *panel);
Please move this up so it is together with the other get_* methods, in
alphabetic order. That is, right after get_modes(), and then this also
matches the order in the .c file with is extra bonus.
With the two fixes:
Reviewed-by: Sam Ravnborg <s...@ravnborg.org>
> };
>
> /**
> @@ -202,6 +211,7 @@ int drm_panel_enable(struct drm_panel *panel);
> int drm_panel_disable(struct drm_panel *panel);
>
> int drm_panel_get_modes(struct drm_panel *panel, struct drm_connector
> *connector);
> +enum drm_panel_orientation drm_panel_get_orientation(struct drm_panel
> *panel);
>
> #if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL)
> struct drm_panel *of_drm_find_panel(const struct device_node *np);
> --
> 2.36.1.255.ge46751e96f-goog
