Messages in this thread | | | Subject | Re: [PATCH] media input infrastructure:tw686x... | From | Hans Verkuil <> | Date | Sat, 3 Aug 2019 09:24:59 -0300 |
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Hi Mark,
On 7/31/19 6:32 PM, Mark Balantzyan wrote: > Hi Hans, all, > > Sorry for the poor patching, I am a student and as you may tell still > new to this system. At the time of the patching, I wasn't fully informed > of all the requirements that go into such things, and am still learning. > > Would it be alright if I submit a report instead? In order to, I am > (still, sorry) trying to understand the issue at hand. How in fact may > the release() callback be overridden (by a tw686x-specific function) to > free the dma memory and call video_device_release()? To my understanding > at the time, this was merely a re-implementation of video_device_release > with said requirements and subtraction of extra features from > tw686x_video_free()..
Sorry, you'll need to discuss this with your mentor. I really don't have time to look at reports or anything like that. I'm a media subsystem maintainer, not your mentor. And I expect that you spend time trying to understand the code by looking at how other drivers do this and look at kernel documentation like this:
https://linuxtv.org/downloads/v4l-dvb-apis-new/media_kapi.html
Regards,
Hans
> > This release() callback is called by the V4L2 framework when the > last user > of the device closes its filehandle, so that's a good point to free > all > the memory. Doing it earlier (as the current code does) runs the > risk that someone might > still access that memory, and you don't want that. > > Yes, I definitely don't want that. :) > > Thank you, > Mark >
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