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From: Stephen Boyd <swboyd@chromium.org>
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Date: Wed, 3 Apr 2024 12:51:59 -0700
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Subject: Re: [PATCH v3] phy/qcom-qmp-combo: propagate correct return value at phy_power_on()
To: Kuogee Hsieh <quic_khsieh@quicinc.com>, abel.vesa@linaro.org, agross@kernel.org, 
	airlied@gmail.com, andersson@kernel.org, daniel@ffwll.ch, 
	dianders@chromium.org, dmitry.baryshkov@linaro.org, 
	dri-devel@lists.freedesktop.org, robdclark@gmail.com, sean@poorly.run, 
	vkoul@kernel.org
Cc: quic_abhinavk@quicinc.com, quic_jesszhan@quicinc.com, 
	quic_sbillaka@quicinc.com, marijn.suijten@somainline.org, 
	freedreno@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, 
	linux-kernel@vger.kernel.org
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Quoting Kuogee Hsieh (2024-03-29 12:50:35)
> Currently qmp_combo_dp_power_on() always return 0 in regardless of
> return value of cfg->configure_dp_phy(). This patch propagate
> return value of cfg->configure_dp_phy() all the way back to caller.

Is this found via code inspection or because the phy is failing to power
on sometimes? I ask because I'm looking at a DP bug on Trogdor with
chromeos' v6.6 based kernel and wondering if this is related.

Also, is the call to phy_power_on() going to be checked in
the DP driver?

 $ git grep -n phy_power_on -- drivers/gpu/drm/msm/dp/
 drivers/gpu/drm/msm/dp/dp_ctrl.c:1453:  phy_power_on(phy);