diff mbox series

[v2] drm/bridge: Add 200ms delay to wait FW HPD status stable

Message ID 20230922093450.3574349-1-xji@analogixsemi.com (mailing list archive)
State Accepted
Headers show
Series [v2] drm/bridge: Add 200ms delay to wait FW HPD status stable | expand

Commit Message

Xin Ji Sept. 22, 2023, 9:34 a.m. UTC 
For the no-interrupt design (sink device is panel, polling HPD
status when chip power on), anx7625 FW has more than 200ms HPD
de-bounce time in FW, for the safety to get HPD status, driver
better to wait 200ms before HPD detection after OS resume back.

Signed-off-by: Xin Ji <xji@analogixsemi.com>
---
 drivers/gpu/drm/bridge/analogix/anx7625.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Robert Foss Sept. 25, 2023, 10:48 a.m. UTC | #1 
On Fri, 22 Sep 2023 17:34:49 +0800, Xin Ji wrote:
> For the no-interrupt design (sink device is panel, polling HPD
> status when chip power on), anx7625 FW has more than 200ms HPD
> de-bounce time in FW, for the safety to get HPD status, driver
> better to wait 200ms before HPD detection after OS resume back.
> 
> 

Applied, thanks!

[1/1] drm/bridge: Add 200ms delay to wait FW HPD status stable
      https://cgit.freedesktop.org/drm/drm-misc/commit/?id=330140d7319f



Rob
diff mbox series

Patch

diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index 51abe42c639e..8f740154707d 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -1464,6 +1464,9 @@  static int _anx7625_hpd_polling(struct anx7625_data *ctx,
 	if (ctx->pdata.intp_irq)
 		return 0;
 
+	/* Delay 200ms for FW HPD de-bounce */
+	msleep(200);
+
 	ret = readx_poll_timeout(anx7625_read_hpd_status_p0,
 				 ctx, val,
 				 ((val & HPD_STATUS) || (val < 0)),