diff options
author | Maxime Ripard <maxime.ripard@free-electrons.com> | 2017-02-28 18:36:51 +0300 |
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committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2017-03-02 10:12:15 +0300 |
commit | 0f3bbe074dd179dfbdaabcc601086bc4f6ab885b (patch) | |
tree | 16e8bfb3bac288170abacfebf2827e1d45c3d0de /drivers/gpu/drm/drm_fb_helper.c | |
parent | 35f5022fbe9b05ea7ab479f299dc1b63b0ceb8c6 (diff) | |
download | linux-0f3bbe074dd179dfbdaabcc601086bc4f6ab885b.tar.xz |
drm/fb-helper: implement ioctl FBIO_WAITFORVSYNC
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>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/gpu/drm/drm_fb_helper.c')
-rw-r--r-- | drivers/gpu/drm/drm_fb_helper.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 2c92ccf5266a..45fde2ffef2a 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -1245,6 +1245,74 @@ 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_ops.fb_check_var * @var: screeninfo to check * @info: fbdev registered by the helper |