drm/tilcdc: Take crtc modeset lock while updating the crtc clock rate

Take crtc modeset lock while updating the crtc clock rate. To avoid a race in tilcdc_crtc_update_clk(), we do not want crtc mode to change while we update crtc clock. Signed-off-by: Jyri Sarha <[email protected]> Reviewed-by: Tomi Valkeinen <[email protected]>
dlech · Sep 7, 2016 · 10ca4f3 · 10ca4f3
1 parent 46a897f
commit 10ca4f3
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_drv.c b/drivers/gpu/drm/tilcdc/tilcdc_drv.c
@@ -184,10 +184,13 @@ static int cpufreq_transition(struct notifier_block *nb,
 {
 	struct tilcdc_drm_private *priv = container_of(nb,
 			struct tilcdc_drm_private, freq_transition);
+
 	if (val == CPUFREQ_POSTCHANGE) {
 		if (priv->lcd_fck_rate != clk_get_rate(priv->clk)) {
+			drm_modeset_lock_crtc(priv->crtc, NULL);
 			priv->lcd_fck_rate = clk_get_rate(priv->clk);
 			tilcdc_crtc_update_clk(priv->crtc);
+			drm_modeset_unlock_crtc(priv->crtc);
 		}
 	}