Commit 71427795 authored by Ville Syrjälä's avatar Ville Syrjälä
Browse files

drm: Include the encoder itself in possible_clones 



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: default avatarThomas Zimmermann <tzimmermann@suse.de>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211162208.16224-2-ville.syrjala@linux.intel.com


Reviewed-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
parent a212d6a5

drivers/gpu/drm/drm_crtc_internal.h

+1 −0
Original line number Diff line number Diff line
@@ -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);

drivers/gpu/drm/drm_drv.c

+3 −0
Original line number Diff line number Diff line
@@ -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);

drivers/gpu/drm/drm_mode_config.c

+19 −0
Original line number Diff line number Diff line
@@ -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);

}

include/drm/drm_encoder.h

+3 −1
Original line number Diff line number Diff line
@@ -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.

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