On Fri, Sep 12, 2025 at 09:23:05AM +0800, Yongbang Shi wrote: > > > On Thu, Sep 11, 2025 at 05:32:40PM +0800, Yongbang Shi wrote: > > > > On Thu, Aug 14, 2025 at 08:19:41PM +0800, Yongbang Shi wrote: > > > > > > On Wed, Aug 13, 2025 at 05:42:29PM +0800, Yongbang Shi wrote: > > > > > > > From: Baihan Li <libai...@huawei.com> > > > > > > > > > > > > > > The debouncing when HPD pulled out still remains sometimes, 200ms > > > > > > > still can > > > > > > > not ensure helper_detect() is correct. So add a flag to hold the > > > > > > > sink > > > > > > > status, and changed detect_ctx() functions by using flag to check > > > > > > > status. > > > > > > THis doesn't explain what is wrong with > > > > > > drm_connector_helper_detect_from_ddc(). In the end, this function > > > > > > doesn't use the HPD pin. > > > > > I'm sorry about the misunderstanding. > > > > > The issue is that after plugging or unplugging the monitor, the > > > > > driver takes no action sometimes > > > > > even though an interrupt is triggered. The root cause is that > > > > > drm_connector_helper_detect_from_ddc() > > > > > still returns connected status when the monitor is unplugged. > > > > > And I will fix the way in the end. > > > > Can you perform a normal DP detection: read DPCD and check that there is > > > > a DPRX attached and that it's either non-branch device or it has one or > > > > more sinks? > > > I'm very sorry that I didn't get the last sentence's asking before. > > > It's a non-branch device. We just connect a DP monitor. > > Somebody might connect a different configuration than the one that you > > are using. > > Okay, I can add the check drm_dp_is_branch() in the DP's detect_ctx() to > intercept branch devices, is that good?
My suggestion is to implement DP detection in the way it's done by other DP drivers. -- With best wishes Dmitry
