diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 7e29d5340a17..4b0dd20bccb8 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -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 @@ err_free_buffer: } 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. diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h index c134bbcfd2e9..5db08c8f1d25 100644 --- a/include/drm/drm_fb_helper.h +++ b/include/drm/drm_fb_helper.h @@ -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