drm: lcdif: Check consistent bus format and flags across first bridges

The single LCDIF embedded in i.MX93 SoC may drive multiple displays
simultaneously.  Check bus format and flags across first bridges in
->atomic_check() to ensure they are consistent.  This is a preparation
for adding i.MX93 LCDIF support.

Acked-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Liu Ying <victor.liu@nxp.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230510092450.4024730-5-victor.liu@nxp.com

diff --git a/drivers/gpu/drm/mxsfb/lcdif_drv.c b/drivers/gpu/drm/mxsfb/lcdif_drv.c
index 6fb5b469ee5a01a14c5737e92d371458018a2905..e816f87828fbcad34d7246f4b8984f458bb03295 100644 (file)
--- a/drivers/gpu/drm/mxsfb/lcdif_drv.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_drv.c
@@ -52,8 +52,6 @@ static int lcdif_attach_bridge(struct lcdif_drm_private *lcdif)
        if (ret)
                return dev_err_probe(drm->dev, ret, "Failed to attach bridge\n");
 
-       lcdif->bridge = bridge;
-
        return 0;
 }
 

diff --git a/drivers/gpu/drm/mxsfb/lcdif_drv.h b/drivers/gpu/drm/mxsfb/lcdif_drv.h
index 6cdba6e20c02b470b9b3484143a17675547167b7..aa6d099a1897cd391c34058689205bc4f3aa8a63 100644 (file)
--- a/drivers/gpu/drm/mxsfb/lcdif_drv.h
+++ b/drivers/gpu/drm/mxsfb/lcdif_drv.h
@@ -31,7 +31,6 @@ struct lcdif_drm_private {
        } planes;
        struct drm_crtc                 crtc;
        struct drm_encoder              encoder;
-       struct drm_bridge               *bridge;
 };
 
 static inline struct lcdif_drm_private *

diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
index fab2253e478646678b8cd26e7c669c17cc1fab20..e13382beb53e8f5bbe1371e8abcce1ec54496276 100644 (file)
--- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
@@ -17,6 +17,7 @@
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_bridge.h>
 #include <drm/drm_color_mgmt.h>
+#include <drm/drm_connector.h>
 #include <drm/drm_crtc.h>
 #include <drm/drm_encoder.h>
 #include <drm/drm_fb_dma_helper.h>
@@ -424,15 +425,19 @@ static int lcdif_crtc_atomic_check(struct drm_crtc *crtc,
                                   struct drm_atomic_state *state)
 {
        struct drm_device *drm = crtc->dev;
-       struct lcdif_drm_private *lcdif = to_lcdif_drm_private(drm);
        struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state,
                                                                          crtc);
        struct lcdif_crtc_state *lcdif_crtc_state = to_lcdif_crtc_state(crtc_state);
        bool has_primary = crtc_state->plane_mask &
                           drm_plane_mask(crtc->primary);
+       struct drm_connector_state *connector_state;
+       struct drm_connector *connector;
+       struct drm_encoder *encoder;
        struct drm_bridge_state *bridge_state;
-       struct drm_bridge *bridge = lcdif->bridge;
-       int ret;
+       struct drm_bridge *bridge;
+       u32 bus_format, bus_flags;
+       bool format_set = false, flags_set = false;
+       int ret, i;
 
        /* The primary plane has to be enabled when the CRTC is active. */
        if (crtc_state->active && !has_primary)
@@ -442,29 +447,58 @@ static int lcdif_crtc_atomic_check(struct drm_crtc *crtc,
        if (ret)
                return ret;
 
-       bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
-       if (!bridge_state)
-               lcdif_crtc_state->bus_format = MEDIA_BUS_FMT_FIXED;
-       else
-               lcdif_crtc_state->bus_format = bridge_state->input_bus_cfg.format;
-
-       if (lcdif_crtc_state->bus_format == MEDIA_BUS_FMT_FIXED) {
-               dev_warn_once(drm->dev,
-                             "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
-                             "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
-               lcdif_crtc_state->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
-       } else if (!lcdif_crtc_state->bus_format) {
-               /* If all else fails, default to RGB888_1X24 */
-               lcdif_crtc_state->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+       /* Try to find consistent bus format and flags across first bridges. */
+       for_each_new_connector_in_state(state, connector, connector_state, i) {
+               if (!connector_state->crtc)
+                       continue;
+
+               encoder = connector_state->best_encoder;
+
+               bridge = drm_bridge_chain_get_first_bridge(encoder);
+               if (!bridge)
+                       continue;
+
+               bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
+               if (!bridge_state)
+                       bus_format = MEDIA_BUS_FMT_FIXED;
+               else
+                       bus_format = bridge_state->input_bus_cfg.format;
+
+               if (bus_format == MEDIA_BUS_FMT_FIXED) {
+                       dev_warn(drm->dev,
+                                "[ENCODER:%d:%s]'s bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
+                                "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n",
+                                encoder->base.id, encoder->name);
+                       bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+               } else if (!bus_format) {
+                       /* If all else fails, default to RGB888_1X24 */
+                       bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+               }
+
+               if (!format_set) {
+                       lcdif_crtc_state->bus_format = bus_format;
+                       format_set = true;
+               } else if (lcdif_crtc_state->bus_format != bus_format) {
+                       DRM_DEV_DEBUG_DRIVER(drm->dev, "inconsistent bus format\n");
+                       return -EINVAL;
+               }
+
+               if (bridge->timings)
+                       bus_flags = bridge->timings->input_bus_flags;
+               else if (bridge_state)
+                       bus_flags = bridge_state->input_bus_cfg.flags;
+               else
+                       bus_flags = 0;
+
+               if (!flags_set) {
+                       lcdif_crtc_state->bus_flags = bus_flags;
+                       flags_set = true;
+               } else if (lcdif_crtc_state->bus_flags != bus_flags) {
+                       DRM_DEV_DEBUG_DRIVER(drm->dev, "inconsistent bus flags\n");
+                       return -EINVAL;
+               }
        }
 
-       if (bridge->timings)
-               lcdif_crtc_state->bus_flags = bridge->timings->input_bus_flags;
-       else if (bridge_state)
-               lcdif_crtc_state->bus_flags = bridge_state->input_bus_cfg.flags;
-       else
-               lcdif_crtc_state->bus_flags = 0;
-
        return 0;
 }