Hi Jingoo, On 08/20/2015 01:11 AM, Jingoo Han wrote: > On 2015. 8. 19., at PM 11:52, Yakir Yang <ykk at rock-chips.com> wrote: >> Some edp screen with no hpd signal would need some delay time >> to ensure that screen would be ready for work, so we can expand >> the delay time in hpd detect function, it works prefectly on my >> rk3288 sdk board. > Then, this delay has a dependency on the "rk3288 sdk" board. > Also, if the delay time is expanded, the booting time of some Exybos boards will be increased unnecessarily. :-( > > So, please add new DT property such as 'hpd-delay' that can be added to board DT files. > > If there is not that DT property in DT files, the default value '10' will written to a variable such as 'unsigned int hpd_delay'. > If there is the DT property in DT files, the delay value will written to the variable when parsing DT values > and will be used in analogix_dp_detect_hpd(). > > What I want to say is that there should not be harmful effect on the existing Exynos boards, due to unrelated reasons. Yeah, you are right, I made an mistake here. And I want to put this delay to "need-force-hpd" code, cause this property is for the no-hpd-signal eDP screen. But strangely, with my this series, I don't need the expand delay any more, I am not sure which change improved this, I guess those delay time should come from drm core ? Whatever seems we don't need this delay for now, and if I can find the exact reason and realize I still need this delay, I prefer to add those delay in "need-force-hpd" code. Thanks, - Yakir > Best regards, > Jingoo Han > >> Signed-off-by: Yakir Yang <ykk at rock-chips.com> >> --- >> Changes in v3: None >> Changes in v2: None >> >> drivers/gpu/drm/bridge/analogix_dp_core.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/bridge/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix_dp_core.c >> index 99870f7..75dd44a 100644 >> --- a/drivers/gpu/drm/bridge/analogix_dp_core.c >> +++ b/drivers/gpu/drm/bridge/analogix_dp_core.c >> @@ -68,7 +68,7 @@ static int analogix_dp_detect_hpd(struct analogix_dp_device *dp) >> return 0; >> >> timeout_loop++; >> - usleep_range(10, 11); >> + usleep_range(100, 110); >> } >> >> /* >> -- >> 1.9.1 >> >> > >
