diff options
Diffstat (limited to 'drivers/gpu/drm/drm_fb_helper.c')
| -rw-r--r-- | drivers/gpu/drm/drm_fb_helper.c | 28 |
1 files changed, 16 insertions, 12 deletions
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 823fc8f50d85..e3eb3c9a98e3 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -66,19 +66,23 @@ static DEFINE_MUTEX(kernel_fb_helper_lock); * helper functions used by many drivers to implement the kernel mode setting * interfaces. * - * Initialization is done as a four-step process with drm_fb_helper_prepare(), - * drm_fb_helper_init(), drm_fb_helper_single_add_all_connectors() and - * drm_fb_helper_initial_config(). Drivers with fancier requirements than the - * default behaviour can override the third step with their own code. - * Teardown is done with drm_fb_helper_fini() after the fbdev device is - * unregisters using drm_fb_helper_unregister_fbi(). + * Setup fbdev emulation by calling drm_fb_helper_fbdev_setup() and tear it + * down by calling drm_fb_helper_fbdev_teardown(). * - * At runtime drivers should restore the fbdev console by calling - * drm_fb_helper_restore_fbdev_mode_unlocked() from their &drm_driver.lastclose - * callback. They should also notify the fb helper code from updates to the - * output configuration by calling drm_fb_helper_hotplug_event(). For easier - * integration with the output polling code in drm_crtc_helper.c the modeset - * code provides a &drm_mode_config_funcs.output_poll_changed callback. + * Drivers that need to handle connector hotplugging (e.g. dp mst) can't use + * the setup helper and will need to do the whole four-step setup process with + * drm_fb_helper_prepare(), drm_fb_helper_init(), + * drm_fb_helper_single_add_all_connectors(), enable hotplugging and + * drm_fb_helper_initial_config() to avoid a possible race window. + * + * At runtime drivers should restore the fbdev console by using + * drm_fb_helper_lastclose() as their &drm_driver.lastclose callback. + * They should also notify the fb helper code from updates to the output + * configuration by using drm_fb_helper_output_poll_changed() as their + * &drm_mode_config_funcs.output_poll_changed callback. + * + * For suspend/resume consider using drm_mode_config_helper_suspend() and + * drm_mode_config_helper_resume() which takes care of fbdev as well. * * All other functions exported by the fb helper library can be used to * implement the fbdev driver interface by the driver. |