linux-kernel - Re: [PATCH 2/5] media: v4l2-core changes to use media tuner token api

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Wed, 24 Sep 2014 09:30:47 -0600
From:	Shuah Khan <shuahkh@....samsung.com>
To:	Hans Verkuil <hverkuil@...all.nl>, m.chehab@...sung.com,
	akpm@...ux-foundation.org, gregkh@...uxfoundation.org,
	crope@....fi, olebowle@....com, dheitmueller@...nellabs.com,
	ramakrmu@...co.com, sakari.ailus@...ux.intel.com,
	laurent.pinchart@...asonboard.com
CC:	linux-kernel@...r.kernel.org, linux-media@...r.kernel.org,
	Shuah Khan <shuahkh@....samsung.com>
Subject: Re: [PATCH 2/5] media: v4l2-core changes to use media tuner token
 api

On 09/24/2014 05:57 AM, Hans Verkuil wrote:
> Hi Shuah,
> 
> Here is my review...
> 
> On 09/22/2014 05:00 PM, Shuah Khan wrote:
>> Changes to v4l2-core to hold tuner token in v4l2 ioctl that change
>> the tuner modes, and reset the token from fh exit. The changes are
>> limited to vb2 calls that disrupt digital stream. vb1 changes are
>> made in the driver. The following ioctls are changed:
>>
>> S_INPUT, S_OUTPUT, S_FMT, S_TUNER, S_MODULATOR, S_FREQUENCY,
> 
> S_MODULATOR doesn't need to take a token. Certainly not a tuner token,
> since it is a modulator, not a tuner. There aren't many modulator drivers,
> and none of them have different modes.
> 
> The same is true for S_OUTPUT: it deals with outputs, so it has nothing
> to do with tuners since those are for input.
> 
>> S_STD, S_HW_FREQ_SEEK:
>>
>> - hold tuner in shared analog mode before calling appropriate
>>    ops->vidioc_s_*
>> - return leaving tuner in shared mode.
>> - Note that S_MODULATOR is now implemented in the core
>>    previously FCN.
>>
>> QUERYSTD:
>> - hold tuner in shared analog mode before calling
>>    ops->vidioc_querystd
>> - return after calling put tuner - this simply decrements the
>>    owners. Leaves tuner in shared analog mode if owners > 0
> 
> I would handle QUERYSTD the same as the ones in the first group.
> It's a fair assumption that once you call QUERYSTD you expect to
> switch the tuner to analog mode and keep it there.
> 
> I'm missing STREAMON in this list as well.
> 
> With regards to G_TUNER and ENUM_INPUT, I will reply to the post that
> discusses that topic.

Hans,

Didn't see you address G_TUNER and ENUM_INPUT in your other response.
Hope I didn't miss it.

thanks,
-- Shuah


-- 
Shuah Khan
Sr. Linux Kernel Developer
Samsung Research America (Silicon Valley)
shuahkh@....samsung.com | (970) 217-8978
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/