drm: sti: clear all mixer control
Make sure that mixer control register is correctly reset
before use it.
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
diff --git a/drivers/gpu/drm/sti/sti_mixer.c b/drivers/gpu/drm/sti/sti_mixer.c
index 79f369d..6bcdf3f 100644
--- a/drivers/gpu/drm/sti/sti_mixer.c
+++ b/drivers/gpu/drm/sti/sti_mixer.c
@@ -215,6 +215,15 @@
return 0;
}
+void sti_mixer_clear_all_layers(struct sti_mixer *mixer)
+{
+ u32 val;
+
+ DRM_DEBUG_DRIVER("%s clear all layer\n", sti_mixer_to_str(mixer));
+ val = sti_mixer_reg_read(mixer, GAM_MIXER_CTL) & 0xFFFF0000;
+ sti_mixer_reg_write(mixer, GAM_MIXER_CTL, val);
+}
+
void sti_mixer_set_matrix(struct sti_mixer *mixer)
{
unsigned int i;