Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Subject: Re: [RFC PATCH v5 13/14] media: tegra-video: Add CSI MIPI pads
 calibration
To:     Sowjanya Komatineni <skomatineni@nvidia.com>,
        thierry.reding@gmail.com, jonathanh@nvidia.com, frankc@nvidia.com,
        hverkuil@xs4all.nl, sakari.ailus@iki.fi, robh+dt@kernel.org,
        helen.koike@collabora.com
Cc:     sboyd@kernel.org, gregkh@linuxfoundation.org,
        linux-media@vger.kernel.org, devicetree@vger.kernel.org,
        linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-i2c@vger.kernel.org
References: <1595883452-17343-1-git-send-email-skomatineni@nvidia.com>
 <1595883452-17343-14-git-send-email-skomatineni@nvidia.com>
 <c3d40261-9d77-3634-3e04-f20efad9d3d8@gmail.com>
 <01ee0805-3d57-d857-48e3-5c2245cd4500@nvidia.com>
From:   Dmitry Osipenko <digetx@gmail.com>
Message-ID: <2ec535c9-55e8-8834-6002-36c75aeb097c@gmail.com>
Date:   Thu, 30 Jul 2020 02:25:55 +0300
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101
 Thunderbird/68.10.0
MIME-Version: 1.0
In-Reply-To: <01ee0805-3d57-d857-48e3-5c2245cd4500@nvidia.com>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

28.07.2020 18:59, Sowjanya Komatineni пишет:
...
>>> +        ret = tegra_mipi_finish_calibration(csi_chan->mipi);
>>> +        if (ret < 0)
>>> +            dev_err(csi_chan->csi->dev,
>>> +                "MIPI calibration failed: %d\n", ret);
>> Doesn't v4l2_subdev_call(OFF) need to be invoked here on error?
> 
> Not required as on error streaming fails and runtime PM will turn off
> power anyway.

I see that camera drivers bump theirs RPM on s_stream=1, and thus,
s_stream=0 should be invoked in order to balance the RPM. What am I missing?

https://elixir.bootlin.com/linux/v5.8-rc4/source/drivers/media/i2c/ov2740.c#L634

> Also we only did csi subdev s_stream on and during sensor subdev
> s_stream on fail, actual stream dont happen and on tegra side frame
> capture by HW happens only when kthreads run.
Secondly, perhaps a failed calibration isn't a very critical error?
Hence just printing a warning message should be enough.

Could you please make a patch that factors all ON/OFF code paths into a
separate functions? It's a bit difficult to follow the combined code,
especially partial changes in the patches. Thanks in advance!