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References: <20210707092257.1465109-1-maxime@cerno.tech>
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From:   Dave Stevenson <dave.stevenson@raspberrypi.com>
Date:   Wed, 28 Jul 2021 14:52:24 +0100
Message-ID: <CAPY8ntDXZ7ExjKvBMFjd5d3RTfrGCe2TYiXfmjF4bmE+WMFssQ@mail.gmail.com>
Subject: Re: [PATCH v2 0/5] drm/vc4: hdmi: Fix CEC access while disabled
To:     Maxime Ripard <maxime@cerno.tech>
Cc:     DRI Development <dri-devel@lists.freedesktop.org>,
        Daniel Vetter <daniel.vetter@intel.com>,
        David Airlie <airlied@linux.ie>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        Maxime Ripard <mripard@kernel.org>,
        Emma Anholt <emma@anholt.net>,
        Boris Brezillon <bbrezillon@kernel.org>,
        Phil Elwell <phil@raspberrypi.com>,
        Tim Gover <tim.gover@raspberrypi.com>,
        Dom Cobley <dom@raspberrypi.com>,
        linux-rpi-kernel@lists.infradead.org,
        Nicolas Saenz Julienne <nsaenz@kernel.org>,
        Hans Verkuil <hverkuil-cisco@xs4all.nl>,
        LKML <linux-kernel@vger.kernel.org>,
        bcm-kernel-feedback-list@broadcom.com
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Hi Maxime

On Wed, 7 Jul 2021 at 10:23, Maxime Ripard <maxime@cerno.tech> wrote:
>
> Hi,
>
> This series aims at fixing a complete and silent hang when one tries to use CEC
> while the display output is off.
>
> This can be tested with:
>
> echo off > /sys/class/drm/card0-HDMI-A-1/status
> cec-ctl --tuner -p 1.0.0.0
> cec-compliance
>
> This series addresses it by making sure the HDMI controller is powered up as
> soon as the CEC device is opened by the userspace.
>
> Let me know what you think,
> Maxime
>
> Changes from v1:
>   - More fixes
>   - Added a big warning if we try to access a register while the device is
>     disabled.
>   - Fixed the pre_crtc_configure error path
>
> Maxime Ripard (5):
>   drm/vc4: hdmi: Make sure the controller is powered up during bind
>   drm/vc4: hdmi: Rework the pre_crtc_configure error handling
>   drm/vc4: hdmi: Split the CEC disable / enable functions in two
>   drm/vc4: hdmi: Make sure the device is powered with CEC
>   drm/vc4: hdmi: Warn if we access the controller while disabled

Comment made on patch 1.

Patches 2-5:
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

  Dave

>
>  drivers/gpu/drm/vc4/vc4_hdmi.c      | 123 +++++++++++++++++++---------
>  drivers/gpu/drm/vc4/vc4_hdmi_regs.h |   6 ++
>  2 files changed, 89 insertions(+), 40 deletions(-)
>
> --
> 2.31.1
>