[Intel-gfx] [PATCH v1 07/13] drm/probe-helper: add .get_edid() callback

[Jani Nikula]

Add a hook for custom .get_edid() when .get_modes() is not set.

Cc: David Airlie <airl...@linux.ie>
Cc: Daniel Vetter <dan...@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nik...@intel.com>
---
 drivers/gpu/drm/drm_probe_helper.c       | 11 +++++++++--
 include/drm/drm_modeset_helper_vtables.h | 21 ++++++++++++++++++---
 2 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/drm_probe_helper.c 
b/drivers/gpu/drm/drm_probe_helper.c
index 9df17f0ae225..42481dc9e6db 100644
--- a/drivers/gpu/drm/drm_probe_helper.c
+++ b/drivers/gpu/drm/drm_probe_helper.c
@@ -361,12 +361,19 @@ static int drm_helper_probe_get_modes(struct 
drm_connector *connector)
        int count;
 
        if (connector_funcs->get_modes) {
+               /* No point in having both set */
+               drm_WARN_ON_ONCE(connector->dev, connector_funcs->get_edid);
+
                count = connector_funcs->get_modes(connector);
        } else {
                const struct drm_edid *drm_edid;
 
-               /* Note: This requires connector->ddc is set */
-               drm_edid = drm_edid_read(connector);
+               if (connector_funcs->get_edid) {
+                       drm_edid = connector_funcs->get_edid(connector);
+               } else {
+                       /* Note: This requires connector->ddc is set */
+                       drm_edid = drm_edid_read(connector);
+               }
 
                /* Update modes etc. from the EDID */
                count = drm_edid_connector_update(connector, drm_edid);
diff --git a/include/drm/drm_modeset_helper_vtables.h 
b/include/drm/drm_modeset_helper_vtables.h
index b4402bc64e57..f4defbdf1768 100644
--- a/include/drm/drm_modeset_helper_vtables.h
+++ b/include/drm/drm_modeset_helper_vtables.h
@@ -49,6 +49,7 @@
  */
 
 enum mode_set_atomic;
+struct drm_edid;
 struct drm_writeback_connector;
 struct drm_writeback_job;
 
@@ -894,9 +895,10 @@ struct drm_connector_helper_funcs {
         * libraries always call this with the &drm_mode_config.connection_mutex
         * held. Because of this it's safe to inspect &drm_connector->state.
         *
-        * This callback is optional. By default, it reads the EDID using
-        * drm_edid_read() and updates the connector display info, modes, and
-        * properties using drm_edid_connector_update().
+        * This callback is optional. By default, it reads the EDID using the
+        * .get_edid() callback if set, drm_edid_read() otherwise, and updates
+        * the connector display info, modes, and properties using
+        * drm_edid_connector_update().
         *
         * RETURNS:
         *
@@ -904,6 +906,19 @@ struct drm_connector_helper_funcs {
         */
        int (*get_modes)(struct drm_connector *connector);
 
+       /**
+        * @get_edid:
+        *
+        * If the get_modes() callback is not set, this function gets called to
+        * retrieve the EDID. This callback is optional. By default,
+        * drm_edid_read() is used.
+        *
+        * This function must return a copy of the EDID; the returned pointer
+        * will be freed using drm_edid_free(). Usually it would be a copy of a
+        * previously cached EDID.
+        */
+       const struct drm_edid *(*get_edid)(struct drm_connector *connector);
+
        /**
         * @detect_ctx:
         *
-- 
2.30.2