From mboxrd@z Thu Jan 1 00:00:00 1970 From: Archit Taneja Subject: Re: [PATCH v5 24/36] drm/bridge: analogix_dp: Reorder plat_data->power_off to happen sooner Date: Wed, 14 Mar 2018 12:20:09 +0530 Message-ID: <6411add8-32ee-a365-9882-061c1383ffd0@codeaurora.org> References: <20180309222327.18689-1-enric.balletbo@collabora.com> <20180309222327.18689-25-enric.balletbo@collabora.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180309222327.18689-25-enric.balletbo@collabora.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Enric Balletbo i Serra , inki.dae@samsung.com, thierry.reding@gmail.com, hjc@rock-chips.com, seanpaul@chromium.org, airlied@linux.ie, tfiga@chromium.org, heiko@sntech.de Cc: dri-devel@lists.freedesktop.org, dianders@chromium.org, a.hajda@samsung.com, ykk@rock-chips.com, kernel@collabora.com, m.szyprowski@samsung.com, linux-samsung-soc@vger.kernel.org, jy0922.shim@samsung.com, rydberg@bitmath.org, krzk@kernel.org, linux-rockchip@lists.infradead.org, kgene@kernel.org, linux-input@vger.kernel.org, orjan.eide@arm.com, wxt@rock-chips.com, jeffy.chen@rock-chips.com, linux-arm-kernel@lists.infradead.org, mark.yao@rock-chips.com, wzz@rock-chips.com, hl@rock-chips.com, jingoohan1@gmail.com, sw0312.kim@samsung.com, linux-kernel@vger.kernel.org, kyungmin.park@samsung.com, Laurent.pinchart@ideasonboard.com, kuankuan.y@gmail.com, hshi@chromium.org, "Kristian H . Kristensen" List-Id: linux-input@vger.kernel.org On Saturday 10 March 2018 03:53 AM, Enric Balletbo i Serra wrote: > From: Douglas Anderson > > The current user of the analogix power_off is "analogix_dp-rockchip". > That driver does this: > - deactivate PSR > - turn off a clock > > Both of these things (especially deactive PSR) should be done before > we turn the PHY power off and turn off analog power. Let's move the > callback up. > > Note that without this patch (and with > https://patchwork.kernel.org/patch/9553349/ [seanpaul: this patch was > not applied, but it seems like the race can still occur]), I experienced > an error in reboot testing where one thread was at: > > rockchip_drm_psr_deactivate > rockchip_dp_powerdown > analogix_dp_bridge_disable > drm_bridge_disable > > ...and the other thread was at: > > analogix_dp_send_psr_spd > analogix_dp_enable_psr > analogix_dp_psr_set > psr_flush_handler > > The flush handler thread was finding AUX channel errors and eventually > reported "Failed to apply PSR", where I had a kgdb breakpoint. Presumably > the device would have eventually given up and shut down anyway, but it > seems better to fix the order to be more correct. > Reviewed-by: Archit Taneja Thanks, Archit > Cc: Kristian H. Kristensen > Signed-off-by: Douglas Anderson > Signed-off-by: Sean Paul > Signed-off-by: Thierry Escande > Reviewed-by: Andrzej Hajda > Signed-off-by: Enric Balletbo i Serra > Tested-by: Marek Szyprowski > --- > > drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > index 37b16643f14c..eaf93cbd47a8 100644 > --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > @@ -1337,12 +1337,13 @@ static void analogix_dp_bridge_disable(struct drm_bridge *bridge) > } > > disable_irq(dp->irq); > - analogix_dp_set_analog_power_down(dp, POWER_ALL, 1); > - phy_power_off(dp->phy); > > if (dp->plat_data->power_off) > dp->plat_data->power_off(dp->plat_data); > > + analogix_dp_set_analog_power_down(dp, POWER_ALL, 1); > + phy_power_off(dp->phy); > + > clk_disable_unprepare(dp->clock); > > pm_runtime_put_sync(dp->dev); >