[Freedreno] [PATCH v4] drm/msm/dp: return correct connection status after suspend

[Stephen Boyd]

Quoting Kuogee Hsieh (2020-10-13 16:35:22)
> During suspend, dp host controller and hpd block are disabled due to
> both ahb and aux clock are disabled. Therefore hpd plug/unplug interrupts
> will not be generated. At dp_pm_resume(), reinitialize both dp host
> controller and hpd block so that hpd plug/unplug interrupts will be
> generated and handled by driver so that hpd connection state is updated
> correctly. This patch will fix link training flaky issues.
> 
> Changes in v2:
> -- use container_of to cast correct dp_display_private pointer
>    at both dp_pm_suspend() and dp_pm_resume().
> 
> Changes in v3:
> -- replace hpd_state atomic_t  with u32
> 
> Changes in v4
> -- call dp_display_host_deinit() at dp_pm_suspend()
> -- call dp_display_host_init() at msm_dp_display_enable()
> -- fix phy->init_count unbalance which causes link training failed
> 
> Signed-off-by: Kuogee Hsieh <khsieh at codeaurora.org>
> ---

Can we add some sort of Fixes tag? Maybe the beginning of this DP driver
support?

Tested-by: Stephen Boyd <swboyd at chromium.org>