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@xxxxxxxxx>: > On Tue, Feb 14, 2012 at 07:01:25PM -0300, Ezequiel García 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@xxxxxxxxxxxxxxxxx > http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies -- Peter Senna Tschudin peter.senna@xxxxxxxxx gpg id: 48274C36 _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
