From: peter.senna@gmail.com (Peter Senna Tschudin)
To: kernelnewbies@lists.kernelnewbies.org
Subject: [QUESTION] staging/easycap fix
Date: Wed, 15 Feb 2012 12:14:38 -0200 [thread overview]
Message-ID: <CA+MoWDqXAK0W4Tfu+VhqMVbtwu_Fs=4qF8mA=YonN0sMAK+Cmw@mail.gmail.com> (raw)
In-Reply-To: <20120214223914.GB21350@kroah.com>
Ezequiel,
The post: Intro to V4L2:
http://www.linuxfordevices.com/c/a/Linux-For-Devices-Articles/Intro-to-V4L2/
And the post: The VIVI driver; a great starting point for V4L2 driver writers:
http://lwn.net/Articles/203971/
May be useful.
[]'s
Peter
2012/2/14 Greg KH <greg@kroah.com>:
> On Tue, Feb 14, 2012 at 07:01:25PM -0300, Ezequiel Garc?a wrote:
>> Hi Greg,
>>
>> >
>> > It's only "recommended" if you have a compiler that doesn't check for
>> > such foolish things.
>> >
>>
>> Understood. Thanks both.
>>
>> Another question (hope you don't mind me asking so much):
>>
>> I noticed easycap does lots of (redundant?) checks as:
>>
>> pvideo_device = video_devdata(file);
>> if (!pvideo_device) {
>> ? return -EFAULT;
>> }
>>
>> Is this bad, good or doesn't matter?
>> (There are more examples where the check is clearly not needed but
>> this one makes me doubt a bit)
>
> Depends on what video_devdata() does, and how it could ever be NULL.
>
>> Maybe I'm focusing on small issues (as you already pointed out),
>> do you think this kind of patches would be accepted?
>>
>> Of course, I would submit separate patches, one for each change:
>> 1. split probe function
>> 2. remove redundant checks
>> 3. clean comment style
>> ... and so on.
>
> That sounds great.
>
>> Also, I'm reading driver cx231xx as it's also an usb video capture.
>> Do you think it's a good code reference? Can you give me further reference?
>
> I don't know, ask the linux-media developers on their list for a good
> reference driver to follow, they would know best.
>
> thanks,
>
> greg k-h
>
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
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--
Peter Senna Tschudin
peter.senna at gmail.com
gpg id: 48274C36
next prev parent reply other threads:[~2012-02-15 14:14 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CALF0-+UdbqOnQ6ZT0bPiMVCTFWwMQss6XrFqNL6xsugRPVX_qw@mail.gmail.com>
2012-02-14 4:47 ` [QUESTION] staging/easycap fix Ezequiel García
2012-02-14 5:06 ` Greg KH
2012-02-14 5:30 ` Ezequiel García
2012-02-14 5:59 ` Manavendra Nath Manav
2012-02-14 6:26 ` Greg KH
2012-02-14 22:01 ` Ezequiel García
2012-02-14 22:39 ` Greg KH
2012-02-15 14:14 ` Peter Senna Tschudin [this message]
2012-02-16 12:57 ` Ezequiel García
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