[lkml]   [2021]   [Nov]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH] drm/bridge: parade-ps8640: Fix additional suspend/resume at bootup
Through log and waveform, we can see that there will be additional
suspend/resume when booting. This timing does not meet the ps8640 spec.
It seems that the delay of 500ms does not satisfied drm_panel_get_modes.
I increased it to 900ms and it seems that this problem can be solved.
To be safe, I'd just round up to a full 1000.

Signed-off-by: yangcong <>
drivers/gpu/drm/bridge/parade-ps8640.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/bridge/parade-ps8640.c b/drivers/gpu/drm/bridge/parade-ps8640.c
index 0c7aab42b04f..0749fa628bfb 100644
--- a/drivers/gpu/drm/bridge/parade-ps8640.c
+++ b/drivers/gpu/drm/bridge/parade-ps8640.c
@@ -635,13 +635,13 @@ static int ps8640_probe(struct i2c_client *client)
* Powering on ps8640 takes ~300ms. To avoid wasting time on power
- * cycling ps8640 too often, set autosuspend_delay to 500ms to ensure
+ * cycling ps8640 too often, set autosuspend_delay to 1000ms to ensure
* the bridge wouldn't suspend in between each _aux_transfer_msg() call
* during EDID read (~20ms in my experiment) and in between the last
* _aux_transfer_msg() call during EDID read and the _pre_enable() call
* (~100ms in my experiment).
- pm_runtime_set_autosuspend_delay(dev, 500);
+ pm_runtime_set_autosuspend_delay(dev, 1000);
pm_suspend_ignore_children(dev, true);
ret = devm_add_action_or_reset(dev, ps8640_runtime_disable, dev);
 \ /
  Last update: 2021-11-12 09:44    [W:0.061 / U:5.376 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site