Implement legacy framebuffer ioctl FBIO_WAITFORVSYNC in the generic framebuffer emulation driver. Legacy framebuffer users like non kms/drm based OpenGL(ES)/EGL implementations may require the ioctl to synchronize drawing or buffer flip for double buffering. It is tested on the i.MX6.
Signed-off-by: Maxime Ripard maxime.ripard@free-electrons.com Tested-by: Neil Armstrong narmstrong@baylibre.com --- drivers/gpu/drm/drm_fb_helper.c | 68 ++++++++++++++++++++++++++++++++++- include/drm/drm_fb_helper.h | 12 +++++- 2 files changed, 79 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index c6de87abaca8..8ac8716c023a 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -1240,6 +1240,74 @@ int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info) EXPORT_SYMBOL(drm_fb_helper_setcmap);
/** + * drm_fb_helper_ioctl - legacy ioctl implementation + * @info: fbdev registered by the helper + * @cmd: ioctl command + * @arg: ioctl argument + * + * A helper to implement the standard fbdev ioctl. Only + * FBIO_WAITFORVSYNC is implemented for now. + */ +int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd, + unsigned long arg) +{ + struct drm_fb_helper *fb_helper = info->par; + struct drm_device *dev = fb_helper->dev; + struct drm_mode_set *mode_set; + struct drm_crtc *crtc; + int ret = 0; + + mutex_lock(&dev->mode_config.mutex); + if (!drm_fb_helper_is_bound(fb_helper)) { + ret = -EBUSY; + goto unlock; + } + + switch (cmd) { + case FBIO_WAITFORVSYNC: + /* + * Only consider the first CRTC. + * + * This ioctl is supposed to take the CRTC number as + * an argument, but in fbdev times, what that number + * was supposed to be was quite unclear, different + * drivers were passing that argument differently + * (some by reference, some by value), and most of the + * userspace applications were just hardcoding 0 as an + * argument. + * + * The first CRTC should be the integrated panel on + * most drivers, so this is the best choice we can + * make. If we're not smart enough here, one should + * just consider switch the userspace to KMS. + */ + mode_set = &fb_helper->crtc_info[0].mode_set; + crtc = mode_set->crtc; + + /* + * Only wait for a vblank event if the CRTC is + * enabled, otherwise just don't do anythintg, + * not even report an error. + */ + ret = drm_crtc_vblank_get(crtc); + if (!ret) { + drm_crtc_wait_one_vblank(crtc); + drm_crtc_vblank_put(crtc); + } + + ret = 0; + goto unlock; + default: + ret = -ENOTTY; + } + +unlock: + mutex_unlock(&dev->mode_config.mutex); + return ret; +} +EXPORT_SYMBOL(drm_fb_helper_ioctl); + +/** * drm_fb_helper_check_var - implementation for ->fb_check_var * @var: screeninfo to check * @info: fbdev registered by the helper diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h index 975deedd593e..2891888c6e41 100644 --- a/include/drm/drm_fb_helper.h +++ b/include/drm/drm_fb_helper.h @@ -230,7 +230,8 @@ struct drm_fb_helper { .fb_blank = drm_fb_helper_blank, \ .fb_pan_display = drm_fb_helper_pan_display, \ .fb_debug_enter = drm_fb_helper_debug_enter, \ - .fb_debug_leave = drm_fb_helper_debug_leave + .fb_debug_leave = drm_fb_helper_debug_leave, \ + .fb_ioctl = drm_fb_helper_ioctl
#ifdef CONFIG_DRM_FBDEV_EMULATION void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper, @@ -286,6 +287,9 @@ void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info);
+int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd, + unsigned long arg); + int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper); int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel); int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper); @@ -377,6 +381,12 @@ static inline int drm_fb_helper_setcmap(struct fb_cmap *cmap, return 0; }
+static inline int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd, + unsigned long arg) +{ + return 0; +} + static inline void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper) { }