Re: [PATCH 15/31] media: dvb-frontend invoke enable/disable_source handlers
From: Mauro Carvalho Chehab <hidden>
Date: 2016-01-28 17:32:07
Also in:
alsa-devel, linux-media, lkml
From: Mauro Carvalho Chehab <hidden>
Date: 2016-01-28 17:32:07
Also in:
alsa-devel, linux-media, lkml
Em Thu, 28 Jan 2016 09:59:38 -0700 Shuah Khan [off-list ref] escreveu:
On 01/28/2016 09:07 AM, One Thousand Gnomes wrote:quoted
On Thu, 28 Jan 2016 13:53:04 -0200 Mauro Carvalho Chehab [off-list ref] wrote:quoted
Em Wed, 6 Jan 2016 13:27:04 -0700 Shuah Khan [off-list ref] escreveu:quoted
Checking for tuner availability from frontend thread start disrupts video stream. Change to check for tuner and start pipeline from frontend open instead and stop pipeline from frontend release.That's wrong, as DVB can be opened on read-only mode, where it won't be changing anything.Correct. Please check the code. Tuner availability check is done when the device is opened in Write mode in the following conditional. if ((file->f_flags & O_ACCMODE) != O_RDONLY) {
OK. Thanks! Mauro , I don't think POSIX allows to return an error like EBUSY
quoted
It doesn't document all the errors you may return. Quite a lot of kernel drivers return EBUSY when they are "single open" things. POSIX documents certain cases that *must* error and what the error code is. It documents certain possible failures and what their error code is. Beyond that it's up to you.Returning EBUSY clearly indicates the reason why the device can't be opened in this case. thanks, -- Shuah
Thanks! Mauro