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

From: Stephen Boyd <swboyd@chromium.org>
To: Kuogee Hsieh <quic_khsieh@quicinc.com>,
	agross@kernel.org, airlied@linux.ie, bjorn.andersson@linaro.org,
	daniel@ffwll.ch, dmitry.baryshkov@linaro.org,
	robdclark@gmail.com, sean@poorly.run, vkoul@kernel.org
Cc: quic_abhinavk@quicinc.com, aravindh@codeaurora.org,
	freedreno@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
	linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org,
	Kuogee Hsieh <khsieh@codeaurora.org>
Subject: Re: [PATCH v4] drm/msm/dp: do not initialize phy until plugin interrupt received
Date: Thu, 2 Dec 2021 18:41:07 -0800	[thread overview]
Message-ID: <CAE-0n51-=qTWfBVPFEmpEb7md6cg5O__bhydXTUb+=8dRqCuqg@mail.gmail.com> (raw)
In-Reply-To: <1636493893-7600-1-git-send-email-quic_khsieh@quicinc.com>

Quoting Kuogee Hsieh (2021-11-09 13:38:13)
> From: Kuogee Hsieh <khsieh@codeaurora.org>
>
> 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@quicinc.com>
> ---

Can you please resend this based on the msm-next branch[1]? It doesn't
apply now that other patches have been applied.

[1] https://gitlab.freedesktop.org/drm/msm.git msm-next

>  drivers/gpu/drm/msm/dp/dp_ctrl.c    | 87 ++++++++++++++++---------------------
>  drivers/gpu/drm/msm/dp/dp_ctrl.h    |  9 ++--
>  drivers/gpu/drm/msm/dp/dp_display.c | 83 ++++++++++++++++++++++++++---------
>  3 files changed, 105 insertions(+), 74 deletions(-)
>