Commit 1aed9509 authored by Thomas Zimmermann's avatar Thomas Zimmermann
Browse files

drm/fb-helper: Remove return value from drm_fbdev_generic_setup() 



Generic fbdev emulation is a DRM client. Drivers should invoke the
setup function, but not depend on its success. Hence remove the return
value.

v3:
	* document stricter requirements for call sequence
v2:
	* warn if fbdev device has not been registered yet
	* document the new behavior
	* convert the existing warning to the new dev_ interface

Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: default avatarSam Ravnborg <sam@ravnborg.org>
Reviewed-by: default avatarNoralf Trønnes <noralf@tronnes.org>
Acked-by: default avatarSam Ravnborg <sam@ravnborg.org>
Acked-by: default avatarGerd Hoffmann <kraxel@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200408082641.590-11-tzimmermann@suse.de
parent 3662cd19

drivers/gpu/drm/drm_fb_helper.c

+12 −11
Original line number Diff line number Diff line
@@ -2170,6 +2170,8 @@ static const struct drm_client_funcs drm_fbdev_client_funcs = { 
 *

 * This function sets up generic fbdev emulation for drivers that supports

 * dumb buffers with a virtual address and that can be mmap'ed.

 * drm_fbdev_generic_setup() shall be called after the DRM driver registered

 * the new DRM device with drm_dev_register().

 *

 * Restore, hotplug events and teardown are all taken care of. Drivers that do

 * suspend/resume need to call drm_fb_helper_set_suspend_unlocked() themselves.
@@ -2186,29 +2188,30 @@ static const struct drm_client_funcs drm_fbdev_client_funcs = { 
 * Setup will be retried on the next hotplug event.

 *

 * The fbdev is destroyed by drm_dev_unregister().

 *

 * Returns:

 * Zero on success or negative error code on failure.

 */

int drm_fbdev_generic_setup(struct drm_device *dev, unsigned int preferred_bpp)

void drm_fbdev_generic_setup(struct drm_device *dev,

			     unsigned int preferred_bpp)

{

	struct drm_fb_helper *fb_helper;

	int ret;



	WARN(dev->fb_helper, "fb_helper is already set!\n");

	drm_WARN(dev, !dev->registered, "Device has not been registered.\n");

	drm_WARN(dev, dev->fb_helper, "fb_helper is already set!\n");



	if (!drm_fbdev_emulation)

		return 0;

		return;



	fb_helper = kzalloc(sizeof(*fb_helper), GFP_KERNEL);

	if (!fb_helper)

		return -ENOMEM;

	if (!fb_helper) {

		drm_err(dev, "Failed to allocate fb_helper\n");

		return;

	}



	ret = drm_client_init(dev, &fb_helper->client, "fbdev", &drm_fbdev_client_funcs);

	if (ret) {

		kfree(fb_helper);

		drm_err(dev, "Failed to register client: %d\n", ret);

		return ret;

		return;

	}



	if (!preferred_bpp)
@@ -2222,8 +2225,6 @@ int drm_fbdev_generic_setup(struct drm_device *dev, unsigned int preferred_bpp) 
		drm_dbg_kms(dev, "client hotplug ret=%d\n", ret);



	drm_client_register(&fb_helper->client);



	return 0;

}

EXPORT_SYMBOL(drm_fbdev_generic_setup);

include/drm/drm_fb_helper.h

+3 −2
Original line number Diff line number Diff line
@@ -269,7 +269,8 @@ int drm_fb_helper_debug_leave(struct fb_info *info); 
void drm_fb_helper_lastclose(struct drm_device *dev);

void drm_fb_helper_output_poll_changed(struct drm_device *dev);



int drm_fbdev_generic_setup(struct drm_device *dev, unsigned int preferred_bpp);

void drm_fbdev_generic_setup(struct drm_device *dev,

			     unsigned int preferred_bpp);

#else

static inline void drm_fb_helper_prepare(struct drm_device *dev,

					struct drm_fb_helper *helper,
@@ -443,7 +444,7 @@ static inline void drm_fb_helper_output_poll_changed(struct drm_device *dev) 
{

}



static inline int

static inline void

drm_fbdev_generic_setup(struct drm_device *dev, unsigned int preferred_bpp)

{

	return 0;

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