drm/tilcdc: WARN if CRTC is touched without CRTC lock

WARN if CRTC is touched without CRTC lock. The crtc functions should
not be called simultaneously from multiple threads. Having the DRM
CRTC lock should take care of that.

Signed-off-by: Jyri Sarha <jsarha@ti.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

diff --git a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
index c1cbabcfb9d4b1f0fc7cf1913f53000a391c5529..639821fb27b7a08f942160e4eaa7a12984f1b690 100644 (file)
--- a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
+++ b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
@@ -153,6 +153,8 @@ static void tilcdc_crtc_enable(struct drm_crtc *crtc)
        struct drm_device *dev = crtc->dev;
        struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
 
+       WARN_ON(!drm_modeset_is_locked(&crtc->mutex));
+
        if (tilcdc_crtc->enabled)
                return;
 
@@ -177,6 +179,8 @@ void tilcdc_crtc_disable(struct drm_crtc *crtc)
        struct drm_device *dev = crtc->dev;
        struct tilcdc_drm_private *priv = dev->dev_private;
 
+       WARN_ON(!drm_modeset_is_locked(&crtc->mutex));
+
        if (!tilcdc_crtc->enabled)
                return;
 
@@ -249,6 +253,8 @@ int tilcdc_crtc_update_fb(struct drm_crtc *crtc,
        struct drm_device *dev = crtc->dev;
        unsigned long flags;
 
+       WARN_ON(!drm_modeset_is_locked(&crtc->mutex));
+
        if (tilcdc_crtc->event) {
                dev_err(dev->dev, "already pending page flip!\n");
                return -EBUSY;
@@ -353,6 +359,8 @@ static void tilcdc_crtc_mode_set_nofb(struct drm_crtc *crtc)
        struct drm_display_mode *mode = &crtc->state->adjusted_mode;
        struct drm_framebuffer *fb = crtc->primary->state->fb;
 
+       WARN_ON(!drm_modeset_is_locked(&crtc->mutex));
+
        if (WARN_ON(!info))
                return;