drm/crtc-helper: Add a drm_crtc_helper_atomic_check() helper

Provides a default CRTC state check handler for CRTCs that only have one
primary plane attached.

There are some drivers that duplicate this logic in their helpers, such as
simpledrm and ssd130x. Factor out this common code into a CRTC helper and
make drivers use it.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20221011165136.469750-5-javierm@redhat.com

diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c
index 457448cc60f70e40418aebde128e74c1aed6d5b3..1f0a270ac98478b054e5b2185813ba2fd5ea6217 100644 (file)
--- a/drivers/gpu/drm/drm_crtc_helper.c
+++ b/drivers/gpu/drm/drm_crtc_helper.c
@@ -421,6 +421,32 @@ done:
 }
 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
 
+/**
+ * drm_crtc_helper_atomic_check() - Helper to check CRTC atomic-state
+ * @crtc: CRTC to check
+ * @state: atomic state object
+ *
+ * Provides a default CRTC-state check handler for CRTCs that only have
+ * one primary plane attached to it.
+ *
+ * This is often the case for the CRTC of simple framebuffers. See also
+ * drm_plane_helper_atomic_check() for the respective plane-state check
+ * helper function.
+ *
+ * RETURNS:
+ * Zero on success, or an errno code otherwise.
+ */
+int drm_crtc_helper_atomic_check(struct drm_crtc *crtc, struct drm_atomic_state *state)
+{
+       struct drm_crtc_state *new_crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
+
+       if (!new_crtc_state->enable)
+               return 0;
+
+       return drm_atomic_helper_check_crtc_primary_plane(new_crtc_state);
+}
+EXPORT_SYMBOL(drm_crtc_helper_atomic_check);
+
 static void
 drm_crtc_helper_disable(struct drm_crtc *crtc)
 {

diff --git a/drivers/gpu/drm/drm_plane_helper.c b/drivers/gpu/drm/drm_plane_helper.c
index 865bd999b187d6af5188eb5ed74b952603b6d713..ba6a9136a065c956eed3a029b5766bfb1c8b89d7 100644 (file)
--- a/drivers/gpu/drm/drm_plane_helper.c
+++ b/drivers/gpu/drm/drm_plane_helper.c
@@ -298,7 +298,9 @@ EXPORT_SYMBOL(drm_plane_helper_destroy);
  * scale and positioning are not expected to change since the plane is always
  * a fullscreen scanout buffer.
  *
- * This is often the case for the primary plane of simple framebuffers.
+ * This is often the case for the primary plane of simple framebuffers. See
+ * also drm_crtc_helper_atomic_check() for the respective CRTC-state check
+ * helper function.
  *
  * RETURNS:
  * Zero on success, or an errno code otherwise.

diff --git a/drivers/gpu/drm/solomon/ssd130x.c b/drivers/gpu/drm/solomon/ssd130x.c
index 0d4ab65233dbdf67b273ac63190198abb5a36e48..f2795f90ea69303e8d235920be491e730f17b87b 100644 (file)
--- a/drivers/gpu/drm/solomon/ssd130x.c
+++ b/drivers/gpu/drm/solomon/ssd130x.c
@@ -20,6 +20,7 @@
 
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc_helper.h>
 #include <drm/drm_damage_helper.h>
 #include <drm/drm_edid.h>
 #include <drm/drm_fb_helper.h>
@@ -645,17 +646,6 @@ static enum drm_mode_status ssd130x_crtc_helper_mode_valid(struct drm_crtc *crtc
        return MODE_OK;
 }
 
-static int ssd130x_crtc_helper_atomic_check(struct drm_crtc *crtc,
-                                           struct drm_atomic_state *new_state)
-{
-       struct drm_crtc_state *new_crtc_state = drm_atomic_get_new_crtc_state(new_state, crtc);
-
-       if (!new_crtc_state->enable)
-               return 0;
-
-       return drm_atomic_helper_check_crtc_primary_plane(new_crtc_state);
-}
-
 /*
  * The CRTC is always enabled. Screen updates are performed by
  * the primary plane's atomic_update function. Disabling clears
@@ -663,7 +653,7 @@ static int ssd130x_crtc_helper_atomic_check(struct drm_crtc *crtc,
  */
 static const struct drm_crtc_helper_funcs ssd130x_crtc_helper_funcs = {
        .mode_valid = ssd130x_crtc_helper_mode_valid,
-       .atomic_check = ssd130x_crtc_helper_atomic_check,
+       .atomic_check = drm_crtc_helper_atomic_check,
 };
 
 static void ssd130x_crtc_reset(struct drm_crtc *crtc)

diff --git a/drivers/gpu/drm/tiny/simpledrm.c b/drivers/gpu/drm/tiny/simpledrm.c
index f03f17f62a56688920b386e4bd1fe9bd7924aacf..cbb100753154ea2d7b7c27c53a305f3155e5a16c 100644 (file)
--- a/drivers/gpu/drm/tiny/simpledrm.c
+++ b/drivers/gpu/drm/tiny/simpledrm.c
@@ -11,6 +11,7 @@
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_state_helper.h>
 #include <drm/drm_connector.h>
+#include <drm/drm_crtc_helper.h>
 #include <drm/drm_damage_helper.h>
 #include <drm/drm_device.h>
 #include <drm/drm_drv.h>
@@ -545,17 +546,6 @@ static enum drm_mode_status simpledrm_crtc_helper_mode_valid(struct drm_crtc *cr
        return drm_crtc_helper_mode_valid_fixed(crtc, mode, &sdev->mode);
 }
 
-static int simpledrm_crtc_helper_atomic_check(struct drm_crtc *crtc,
-                                             struct drm_atomic_state *new_state)
-{
-       struct drm_crtc_state *new_crtc_state = drm_atomic_get_new_crtc_state(new_state, crtc);
-
-       if (!new_crtc_state->enable)
-               return 0;
-
-       return drm_atomic_helper_check_crtc_primary_plane(new_crtc_state);
-}
-
 /*
  * The CRTC is always enabled. Screen updates are performed by
  * the primary plane's atomic_update function. Disabling clears
@@ -563,7 +553,7 @@ static int simpledrm_crtc_helper_atomic_check(struct drm_crtc *crtc,
  */
 static const struct drm_crtc_helper_funcs simpledrm_crtc_helper_funcs = {
        .mode_valid = simpledrm_crtc_helper_mode_valid,
-       .atomic_check = simpledrm_crtc_helper_atomic_check,
+       .atomic_check = drm_crtc_helper_atomic_check,
 };
 
 static const struct drm_crtc_funcs simpledrm_crtc_funcs = {

diff --git a/include/drm/drm_crtc_helper.h b/include/drm/drm_crtc_helper.h
index a6d520d5b6ca787dd787cb765a33211fed7dcb53..1840db247f69d51dbea7d1eaa836e8b9ef9cbd21 100644 (file)
--- a/include/drm/drm_crtc_helper.h
+++ b/include/drm/drm_crtc_helper.h
@@ -50,6 +50,8 @@ bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
                              struct drm_display_mode *mode,
                              int x, int y,
                              struct drm_framebuffer *old_fb);
+int drm_crtc_helper_atomic_check(struct drm_crtc *crtc,
+                                struct drm_atomic_state *state);
 bool drm_helper_crtc_in_use(struct drm_crtc *crtc);
 bool drm_helper_encoder_in_use(struct drm_encoder *encoder);