drm/fb-helper: Finish the generic fbdev emulation

This adds a drm_fbdev_generic_setup() function that sets up generic
fbdev emulation with client callbacks for restore, hotplug and
unregister.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180703160354.59955-7-noralf@tronnes.org
This commit is contained in:
Noralf Trønnes 2018-07-03 18:03:52 +02:00
parent e896c132eb
commit 9060d7f493
2 changed files with 124 additions and 0 deletions

View File

@ -67,6 +67,9 @@ static DEFINE_MUTEX(kernel_fb_helper_lock);
* helper functions used by many drivers to implement the kernel mode setting
* interfaces.
*
* Drivers that support a dumb buffer with a virtual address and mmap support,
* should try out the generic fbdev emulation using drm_fbdev_generic_setup().
*
* Setup fbdev emulation by calling drm_fb_helper_fbdev_setup() and tear it
* down by calling drm_fb_helper_fbdev_teardown().
*
@ -3118,6 +3121,120 @@ int drm_fb_helper_generic_probe(struct drm_fb_helper *fb_helper,
}
EXPORT_SYMBOL(drm_fb_helper_generic_probe);
static const struct drm_fb_helper_funcs drm_fb_helper_generic_funcs = {
.fb_probe = drm_fb_helper_generic_probe,
};
static void drm_fbdev_client_unregister(struct drm_client_dev *client)
{
struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
if (fb_helper->fbdev) {
drm_fb_helper_unregister_fbi(fb_helper);
/* drm_fbdev_fb_destroy() takes care of cleanup */
return;
}
/* Did drm_fb_helper_fbdev_setup() run? */
if (fb_helper->dev)
drm_fb_helper_fini(fb_helper);
drm_client_release(client);
kfree(fb_helper);
}
static int drm_fbdev_client_restore(struct drm_client_dev *client)
{
struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper);
return 0;
}
static int drm_fbdev_client_hotplug(struct drm_client_dev *client)
{
struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
struct drm_device *dev = client->dev;
int ret;
/* If drm_fb_helper_fbdev_setup() failed, we only try once */
if (!fb_helper->dev && fb_helper->funcs)
return 0;
if (dev->fb_helper)
return drm_fb_helper_hotplug_event(dev->fb_helper);
if (!dev->mode_config.num_connector)
return 0;
ret = drm_fb_helper_fbdev_setup(dev, fb_helper, &drm_fb_helper_generic_funcs,
fb_helper->preferred_bpp, 0);
if (ret) {
fb_helper->dev = NULL;
fb_helper->fbdev = NULL;
return ret;
}
return 0;
}
static const struct drm_client_funcs drm_fbdev_client_funcs = {
.owner = THIS_MODULE,
.unregister = drm_fbdev_client_unregister,
.restore = drm_fbdev_client_restore,
.hotplug = drm_fbdev_client_hotplug,
};
/**
* drm_fb_helper_generic_fbdev_setup() - Setup generic fbdev emulation
* @dev: DRM device
* @preferred_bpp: Preferred bits per pixel for the device.
* @dev->mode_config.preferred_depth is used if this is zero.
*
* This function sets up generic fbdev emulation for drivers that supports
* dumb buffers with a virtual address and that can be mmap'ed.
*
* 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.
* Simple drivers might use drm_mode_config_helper_suspend().
*
* Drivers that set the dirty callback on their framebuffer will get a shadow
* fbdev buffer that is blitted onto the real buffer. This is done in order to
* make deferred I/O work with all kinds of buffers.
*
* This function is safe to call even when there are no connectors present.
* Setup will be retried on the next hotplug event.
*
* Returns:
* Zero on success or negative error code on failure.
*/
int drm_fbdev_generic_setup(struct drm_device *dev, unsigned int preferred_bpp)
{
struct drm_fb_helper *fb_helper;
int ret;
if (!drm_fbdev_emulation)
return 0;
fb_helper = kzalloc(sizeof(*fb_helper), GFP_KERNEL);
if (!fb_helper)
return -ENOMEM;
ret = drm_client_new(dev, &fb_helper->client, "fbdev", &drm_fbdev_client_funcs);
if (ret) {
kfree(fb_helper);
return ret;
}
fb_helper->preferred_bpp = preferred_bpp;
drm_fbdev_client_hotplug(&fb_helper->client);
return 0;
}
EXPORT_SYMBOL(drm_fbdev_generic_setup);
/* The Kconfig DRM_KMS_HELPER selects FRAMEBUFFER_CONSOLE (if !EXPERT)
* but the module doesn't depend on any fb console symbols. At least
* attempt to load fbcon to avoid leaving the system without a usable console.

View File

@ -354,6 +354,7 @@ void drm_fb_helper_output_poll_changed(struct drm_device *dev);
int drm_fb_helper_generic_probe(struct drm_fb_helper *fb_helper,
struct drm_fb_helper_surface_size *sizes);
int 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,
@ -595,6 +596,12 @@ drm_fb_helper_generic_probe(struct drm_fb_helper *fb_helper,
return 0;
}
static inline int
drm_fbdev_generic_setup(struct drm_device *dev, unsigned int preferred_bpp)
{
return 0;
}
#endif
static inline int