From e74db610d3134c4e1ab444a00e4391290f0d156e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@linux.intel.com>
Date: Tue, 11 Feb 2020 18:22:02 +0200
Subject: drm: Include the encoder itself in possible_clones
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Git-commit: 714277951deb9f5b22ec3789b61bb45f55c643b8
Patch-mainline: v5.8-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
The docs say possible_clones should always include the encoder itself.
Since most drivers don't want to deal with the complexities of cloning
let's allow them to set possible_clones=0 and instead we'll fix that
up in the core.
We can't put this special case into drm_encoder_init() because drivers
will have to fill up possible_clones after adding all the relevant
encoders. Otherwise they wouldn't know the proper encoder indexes to
use. So we'll just do it just before registering the device.
v2: Don't set the bit if possible_clones!=0 so that the
validation (coming soon) will WARN (Thomas)
Fix up the docs to allow possible_clones==0 (Daniel)
.late_register() is too late, introduce drm_mode_config_validate()
which gets called _before_ we register the char device (Daniel)
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211162208.16224-2-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/drm_crtc_internal.h | 1 +
drivers/gpu/drm/drm_drv.c | 3 +++
drivers/gpu/drm/drm_mode_config.c | 19 +++++++++++++++++++
include/drm/drm_encoder.h | 4 +++-
4 files changed, 26 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_crtc_internal.h b/drivers/gpu/drm/drm_crtc_internal.h
index feba683c12a6..d2d43e0b060b 100644
--- a/drivers/gpu/drm/drm_crtc_internal.h
+++ b/drivers/gpu/drm/drm_crtc_internal.h
@@ -82,6 +82,7 @@ int drm_mode_setcrtc(struct drm_device *dev,
/* drm_mode_config.c */
int drm_modeset_register_all(struct drm_device *dev);
void drm_modeset_unregister_all(struct drm_device *dev);
+void drm_mode_config_validate(struct drm_device *dev);
/* drm_modes.c */
const char *drm_get_mode_status_name(enum drm_mode_status status);
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 7b1a628d1f6e..65a0acb79323 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -946,6 +946,9 @@ int drm_dev_register(struct drm_device *dev, unsigned long flags)
struct drm_driver *driver = dev->driver;
int ret;
+ if (!driver->load)
+ drm_mode_config_validate(dev);
+
if (drm_dev_needs_global_mutex(dev))
mutex_lock(&drm_global_mutex);
diff --git a/drivers/gpu/drm/drm_mode_config.c b/drivers/gpu/drm/drm_mode_config.c
index 08e6eff6a179..75e357c7e84d 100644
--- a/drivers/gpu/drm/drm_mode_config.c
+++ b/drivers/gpu/drm/drm_mode_config.c
@@ -532,3 +532,22 @@ void drm_mode_config_cleanup(struct drm_device *dev)
drm_modeset_lock_fini(&dev->mode_config.connection_mutex);
}
EXPORT_SYMBOL(drm_mode_config_cleanup);
+
+/*
+ * For some reason we want the encoder itself included in
+ * possible_clones. Make life easy for drivers by allowing them
+ * to leave possible_clones unset if no cloning is possible.
+ */
+static void fixup_encoder_possible_clones(struct drm_encoder *encoder)
+{
+ if (encoder->possible_clones == 0)
+ encoder->possible_clones = drm_encoder_mask(encoder);
+}
+
+void drm_mode_config_validate(struct drm_device *dev)
+{
+ struct drm_encoder *encoder;
+
+ drm_for_each_encoder(encoder, dev)
+ fixup_encoder_possible_clones(encoder);
+}
diff --git a/include/drm/drm_encoder.h b/include/drm/drm_encoder.h
index 4370e039c015..34b7213bfab6 100644
--- a/include/drm/drm_encoder.h
+++ b/include/drm/drm_encoder.h
@@ -159,7 +159,9 @@ struct drm_encoder {
* encoders can be used in a cloned configuration, they both should have
* each another bits set.
*
- * In reality almost every driver gets this wrong.
+ * As an exception to the above rule if the driver doesn't implement
+ * any cloning it can leave @possible_clones set to 0. The core will
+ * automagically fix this up by setting the bit for the encoder itself.
*
* Note that since encoder objects can't be hotplugged the assigned indices
* are stable and hence known before registering all objects.
--
2.28.0