Re: [PATCH v4] drm/msm/dp: do not initialize phy until plugin interrupt received

From: Stephen Boyd
Date: Thu Nov 18 2021 - 20:20:22 EST


Quoting Kuogee Hsieh (2021-11-09 13:38:13)
> From: Kuogee Hsieh <khsieh@xxxxxxxxxxxxxx>
>
> Current DP drivers have regulators, clocks, irq and phy are grouped
> together within a function and executed not in a symmetric manner.
> This increase difficulty of code maintenance and limited code scalability.
> This patch divided the driver life cycle of operation into four states,
> resume (including booting up), dongle plugin, dongle unplugged and suspend.
> Regulators, core clocks and irq are grouped together and enabled at resume
> (or booting up) so that the DP controller is armed and ready to receive HPD
> plugin interrupts. HPD plugin interrupt is generated when a dongle plugs
> into DUT (device under test). Once HPD plugin interrupt is received, DP
> controller will initialize phy so that dpcd read/write will function and
> following link training can be proceeded successfully. DP phy will be
> disabled after main link is teared down at end of unplugged HPD interrupt
> handle triggered by dongle unplugged out of DUT. Finally regulators, code
> clocks and irq are disabled at corresponding suspension.
>
> Changes in V2:
> -- removed unnecessary dp_ctrl NULL check
> -- removed unnecessary phy init_count and power_count DRM_DEBUG_DP logs
> -- remove flip parameter out of dp_ctrl_irq_enable()
> -- add fixes tag
>
> Changes in V3:
> -- call dp_display_host_phy_init() instead of dp_ctrl_phy_init() at
> dp_display_host_init() for eDP
>
> Changes in V4:
> -- rewording commit text to match this commit changes
>
> Fixes: e91e3065a806 ("drm/msm/dp: Add DP compliance tests on Snapdragon Chipsets")
>
> Signed-off-by: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>
> ---

What commit is this patch based on?