On Mon, 16 May 2022, Thomas Zimmermann <tzimmermann@xxxxxxx> wrote:
> Provide drm_connector_helper_get_modes_from_ddc() to implement the
> connector's get_modes callback. The new helper updates the connector
> from DDC-provided EDID data.
When adding drm core code, please do *not* prefix with "drm/mgag200".
I, and I believe many people, totally ignore changes to a lot of
drivers, while trying to closely follow drm core changes.
Going forward, I'll be slightly changing what the .get_modes hook is
supposed to do, so this feels like a bit of a detour to me. Anyone
picking this up is up for another refactor later on. Oh well.
BR,
Jani.
PS. There's a // comment in there.
>
> v2:
> * clear property if EDID is NULL in helper
>
> Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
> Reviewed-by: Jocelyn Falempe <jfalempe@xxxxxxxxxx>
> Tested-by: Jocelyn Falempe <jfalempe@xxxxxxxxxx>
> ---
> drivers/gpu/drm/drm_probe_helper.c | 36 ++++++++++++++++++++++++++
> drivers/gpu/drm/mgag200/mgag200_mode.c | 17 +++---------
> include/drm/drm_probe_helper.h | 2 ++
> 3 files changed, 42 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c
> index 682359512996..d77f17867195 100644
> --- a/drivers/gpu/drm/drm_probe_helper.c
> +++ b/drivers/gpu/drm/drm_probe_helper.c
> @@ -964,3 +964,39 @@ bool drm_helper_hpd_irq_event(struct drm_device *dev)
> return changed;
> }
> EXPORT_SYMBOL(drm_helper_hpd_irq_event);
> +
> +/**
> + * drm_connector_helper_get_modes_from_ddc - Updates the connector's EDID
> + * property from the connector's
> + * DDC channel
> + * @connector: The connector
> + *
> + * Returns:
> + * The number of detected display modes.
> + *
> + * Uses a connector's DDC channel to retrieve EDID data and update the
> + * connector's EDID property and display modes. Drivers can use this
> + * function to implement struct &drm_connector_helper_funcs.get_modes
> + * for connectors with a DDC channel.
> + */
> +int drm_connector_helper_get_modes_from_ddc(struct drm_connector *connector)
> +{
> + struct edid *edid;
> + int count = 0;
> +
> + if (!connector->ddc)
> + return 0;
> +
> + edid = drm_get_edid(connector, connector->ddc);
> +
> + // clears property if EDID is NULL
> + drm_connector_update_edid_property(connector, edid);
> +
> + if (edid) {
> + count = drm_add_edid_modes(connector, edid);
> + kfree(edid);
> + }
> +
> + return count;
> +}
> +EXPORT_SYMBOL(drm_connector_helper_get_modes_from_ddc);
> diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
> index b227891d01ec..4c0680dd1a78 100644
> --- a/drivers/gpu/drm/mgag200/mgag200_mode.c
> +++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
> @@ -689,26 +689,17 @@ static void mgag200_disable_display(struct mga_device *mdev)
> * Connector
> */
>
> -static int mga_vga_get_modes(struct drm_connector *connector)
> +static int mgag200_vga_connector_helper_get_modes(struct drm_connector *connector)
> {
> struct mga_device *mdev = to_mga_device(connector->dev);
> - struct mga_connector *mga_connector = to_mga_connector(connector);
> - struct edid *edid;
> - int ret = 0;
> + int ret;
>
> /*
> * Protect access to I/O registers from concurrent modesetting
> * by acquiring the I/O-register lock.
> */
> mutex_lock(&mdev->rmmio_lock);
> -
> - edid = drm_get_edid(connector, &mga_connector->i2c->adapter);
> - if (edid) {
> - drm_connector_update_edid_property(connector, edid);
> - ret = drm_add_edid_modes(connector, edid);
> - kfree(edid);
> - }
> -
> + ret = drm_connector_helper_get_modes_from_ddc(connector);
> mutex_unlock(&mdev->rmmio_lock);
>
> return ret;
> @@ -828,7 +819,7 @@ static void mga_connector_destroy(struct drm_connector *connector)
> }
>
> static const struct drm_connector_helper_funcs mga_vga_connector_helper_funcs = {
> - .get_modes = mga_vga_get_modes,
> + .get_modes = mgag200_vga_connector_helper_get_modes,
> .mode_valid = mga_vga_mode_valid,
> };
>
> diff --git a/include/drm/drm_probe_helper.h b/include/drm/drm_probe_helper.h
> index 48300aa6ca71..c80cab7a53b7 100644
> --- a/include/drm/drm_probe_helper.h
> +++ b/include/drm/drm_probe_helper.h
> @@ -26,4 +26,6 @@ void drm_kms_helper_poll_disable(struct drm_device *dev);
> void drm_kms_helper_poll_enable(struct drm_device *dev);
> bool drm_kms_helper_is_poll_worker(void);
>
> +int drm_connector_helper_get_modes_from_ddc(struct drm_connector *connector);
> +
> #endif
--
Jani Nikula, Intel Open Source Graphics Center
