On Tue, 15 Mar 2022 14:15:20 +0100, Arnaud POULIQUEN wrote: > > Hello, > > > ST Restricted > > > -----Original Message----- > > From: Takashi Iwai <tiwai@xxxxxxx> > > Sent: mardi 15 mars 2022 11:28 > > To: Daniel Palmer <daniel@xxxxxxxx> > > Cc: broonie@xxxxxxxxxx; tiwai@xxxxxxxx; Arnaud POULIQUEN > > <arnaud.pouliquen@xxxxxx>; alsa-devel@xxxxxxxxxxxxxxxx; linux- > > kernel@xxxxxxxxxxxxxxx > > Subject: Re: [PATCH] ASoC: sti: sti_uniperif: Remove driver > > > > On Tue, 15 Mar 2022 10:13:19 +0100, > > Daniel Palmer wrote: > > > > > > This driver seems to be in the "only good for attracting bot generated > > > patches" phase of it's life. > > > > > > It doesn't seem like anyone actually tested the patches that have > > > been applied in the last few years as uni_reader_irq_handler() > > > had a dead lock added to it (it locks the stream, then calls > > > snd_pcm_stop_xrun() which will also lock the stream). > > > > Mea culpa, that was an obvious deadlock I overlooked in the patch > > series. > > > > > Seems best just to remove it. > > > > > > Signed-off-by: Daniel Palmer <daniel@xxxxxxxx> > > > --- > > > I've never used this driver, don't have the hardware etc. > > > I just noticed that this looks broken when debugging my > > > own driver that uses snd_pcm_stop_xrun() and was looking > > > at other users to see if I was using it wrong and noticed > > > this was the only place that locked the stream before > > > calling snd_pcm_stop_xrun(). > > > > > > There are probably some other bits of the driver that > > > should be removed but I didn't look that hard. > > > > > > TL;DR; This driver seems broken, seems like nobody uses > > > it. Maybe it should be deleted? > > > > Yeah, that looks dead. > > > > The platform is still used for instance: > https://lore.kernel.org/all/1d95209f-9cb4-47a3-2696-7a93df7cdc05@xxxxxxxxxxx/ > > So please do not remove the driver Ah, it's always good to see a vital sign! > The issue has not been detected because it is related to an error that > occurs only when we reach the limit of the platform, with application > that stop the stream at same time. > So almost no chance to occur. > > > OTOH, if anyone really wants to keep the stuff, please revert the > > commit dc865fb9e7c2251c9585ff6a7bf185d499db13e4. > > Yes reverting the commit is one solution. > The other is to clean-up the snd_pcm_stream_lock/ snd_pcm_stream_unlock in the > Handler. That would work, but maybe it's safer to keep that lock, as the state change isn't protected by irq_lock but only implicitly by stream lock in start/stop callbacks. thanks, Takashi
