[PATCH] drm: hdlcd: Skip checking the clock provider when CRTC is disabled.

[Liviu Dudau]

Some clock providers (clk-vexpress-osc) trigger a WARN() when the
requested rate falls outside its capabilities, as is the case when
a CRTC gets disabled. Check if the CRTC's new state is enabled and
skip the clk_round_rate() call if it is not.

Reported-by: Vladimir Murzin <vladimir.murzin@xxxxxxx>
Signed-off-by: Liviu Dudau <Liviu.Dudau@xxxxxxx>
Tested-by: Vladimir Murzin <vladimir.murzin@xxxxxxx>
---
 drivers/gpu/drm/arm/hdlcd_crtc.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/arm/hdlcd_crtc.c b/drivers/gpu/drm/arm/hdlcd_crtc.c
index 72b22b805412b..a1387a8bf78c4 100644
--- a/drivers/gpu/drm/arm/hdlcd_crtc.c
+++ b/drivers/gpu/drm/arm/hdlcd_crtc.c
@@ -193,6 +193,10 @@ static int hdlcd_crtc_atomic_check(struct drm_crtc *crtc,
 	struct drm_display_mode *mode = &state->adjusted_mode;
 	long rate, clk_rate = mode->clock * 1000;
 
+	/* if the crtc is disabled, skip the clock check */
+	if (!state->enable)
+		return 0;
+
 	rate = clk_round_rate(hdlcd->clk, clk_rate);
 	if (rate != clk_rate) {
 		/* clock required by mode not supported by hardware */
-- 
2.14.1