On Tue, Feb 06, 2018 at 01:41:29AM +0000, Sasha Levin wrote: > On Mon, Feb 05, 2018 at 11:41:54AM +0000, Mark Brown wrote: > >On Sat, Feb 03, 2018 at 06:00:42PM +0000, Sasha Levin wrote: > >> From: Abhijeet Kumar <abhijeet.kumar@xxxxxxxxx> > >> > >> [ Upstream commit d070f7c703ef26e3db613f24206823f916272fc6 ] > >> > >> In skylake platform, we hear a loud pop noise(0 dB) at start of > >> audio capture power up sequence. This patch removes the pop noise > >> from the recording by adding a delay before enabling ADC. > > > >> switch (event) { > >> case SND_SOC_DAPM_POST_PMU: > >> + msleep(125); > >> regmap_update_bits(nau8825->regmap, NAU8825_REG_ENA_CTRL, > > > >This is another one of these where I'm not convinced that backporting to > >stable isn't going to introduce regressions - it will fix problems on > >some systems but if someone really cares about a startup pop and has > >arranged to do something like discard the start of the audio where the > >pop occurs then this may cut off even more and cause them to miss > >things. > > It might cause regressions for users who worked around the issue, but it > may also fix the issue for users who didn't. I think that in general > we'd rather have mainline and stable trees have the same bugs and > breakage - we don't want surprises when users jump around between > kernels. Yes, being "bug compatible" is a key feature to have :) thanks, greg k-h