On Fri, Jul 26, 2019 at 08:33:35AM +0000, Jan Kotas wrote: > > > > On 26 Jul 2019, at 10:22, Guennadi Liakhovetski <guennadi.liakhovetski@xxxxxxxxxxxxxxx> wrote: > > > > EXTERNAL MAIL > > > > > > Hi Jan, > > > > On Fri, Jul 26, 2019 at 07:47:04AM +0000, Jan Kotas wrote: > >> Hello, > >> > >> I while back I proposed a patch for this, but it went nowhere. > >> > >> https://urldefense.proofpoint.com/v2/url?u=https-3A__patchwork.kernel.org_patch_10887405_&d=DwIBAg&c=aUq983L2pue2FqKFoP6PGHMJQyoJ7kl3s3GZ-_haXqY&r=g7GAQENVXx_RQdyXHInPMg&m=i_0S359hFIVqNgv3fR5_MNzDOHP99trdXszZ-FMiQEE&s=ddktFZYlePh-bC7kXeoKWt4QomupzHATK4FLY4oSWKA&e= > >> Maybe something similar can be implemented? > > > > Yes, I was thinking about checkint -EACCESS too, but then I noticed this code > > in rpm_resume(): > > > > else if (dev->power.disable_depth == 1 && dev->power.is_suspended > > && dev->power.runtime_status == RPM_ACTIVE) > > retval = 1; > > > > i.e. if RT-PM is disabled on the device (but only exactly once?..) and it's > > active and the device is suspended for a system suspend, the function will > > return 1. I don't understand the logic of this code, but it seems to me it > > could break the -EACCESS check? > > > > Hi, > > In such case ret < 0 will not be true, which I think is fine, > if I’m understanding you correctly. Yes, if we just have to distinguish a single case "RT-PM is enabled and it failed." Which is indeed the case here, it seems. However if we want to check whether RT-PM is disabled after a call to, say, pm_runtime_get_sync(), then just checking -EACCESS isn't always enough - there can be cases when RT-PM is disabled and the return code is 1. But yes, just for checking for failures, like here, it should be fine. Thanks Guennadi > >> Jan > >> > >>> On 26 Jul 2019, at 09:39, Guennadi Liakhovetski <guennadi.liakhovetski@xxxxxxxxxxxxxxx> wrote: > >>> > >>> EXTERNAL MAIL > >>> > >>> > >>> Hi Pierre, > >>> > >>> I might be wrong but this doesn't seem right to me. (Supposedly) all RT-PM > >>> functions check for "enabled" internally. The only thing that can happen is > >>> that if RT-PM isn't enabled some of those functions will return an error. > >>> So, in those cases where the return value of RT-PM functions isn't checked, > >>> I don't think you need to do anything. Where it is checked maybe do > >>> > >>> + if (ret < 0 && pm_runtime_enabled(slave->bus->dev)) > >>> > >>> Thanks > >>> Guennadi > >>> > >>> On Thu, Jul 25, 2019 at 06:40:09PM -0500, Pierre-Louis Bossart wrote: > >>>> Not all platforms support runtime_pm for now, let's use runtime_pm > >>>> only when enabled. > >>>> > >>>> Suggested-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx> > >>>> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx> > >>>> --- > >>>> drivers/soundwire/bus.c | 25 ++++++++++++++++--------- > >>>> 1 file changed, 16 insertions(+), 9 deletions(-) > >>>> > >>>> diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c > >>>> index 5ad4109dc72f..0a45dc5713df 100644 > >>>> --- a/drivers/soundwire/bus.c > >>>> +++ b/drivers/soundwire/bus.c > >>>> @@ -332,12 +332,16 @@ int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val) > >>>> if (ret < 0) > >>>> return ret; > >>>> > >>>> - ret = pm_runtime_get_sync(slave->bus->dev); > >>>> - if (ret < 0) > >>>> - return ret; > >>>> + if (pm_runtime_enabled(slave->bus->dev)) { > >>>> + ret = pm_runtime_get_sync(slave->bus->dev); > >>>> + if (ret < 0) > >>>> + return ret; > >>>> + } > >>>> > >>>> ret = sdw_transfer(slave->bus, &msg); > >>>> - pm_runtime_put(slave->bus->dev); > >>>> + > >>>> + if (pm_runtime_enabled(slave->bus->dev)) > >>>> + pm_runtime_put(slave->bus->dev); > >>>> > >>>> return ret; > >>>> } > >>>> @@ -359,13 +363,16 @@ int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, u8 *val) > >>>> slave->dev_num, SDW_MSG_FLAG_WRITE, val); > >>>> if (ret < 0) > >>>> return ret; > >>>> - > >>>> - ret = pm_runtime_get_sync(slave->bus->dev); > >>>> - if (ret < 0) > >>>> - return ret; > >>>> + if (pm_runtime_enabled(slave->bus->dev)) { > >>>> + ret = pm_runtime_get_sync(slave->bus->dev); > >>>> + if (ret < 0) > >>>> + return ret; > >>>> + } > >>>> > >>>> ret = sdw_transfer(slave->bus, &msg); > >>>> - pm_runtime_put(slave->bus->dev); > >>>> + > >>>> + if (pm_runtime_enabled(slave->bus->dev)) > >>>> + pm_runtime_put(slave->bus->dev); > >>>> > >>>> return ret; > >>>> } > >>>> -- > >>>> 2.20.1 > >>>> > >>>> _______________________________________________ > >>>> Alsa-devel mailing list > >>>> Alsa-devel@xxxxxxxxxxxxxxxx > >>>> https://urldefense.proofpoint.com/v2/url?u=https-3A__mailman.alsa-2Dproject.org_mailman_listinfo_alsa-2Ddevel&d=DwIBAg&c=aUq983L2pue2FqKFoP6PGHMJQyoJ7kl3s3GZ-_haXqY&r=g7GAQENVXx_RQdyXHInPMg&m=vETGQLSPeGb7K_ZsXv4Tl3VFfdXzyummTDga97ozJcg&s=LiW4SToh5U0zhnkox54oRhJ1u3vFNbBB9nmzRDuCDjI&e= > >> > >> _______________________________________________ > >> Alsa-devel mailing list > >> Alsa-devel@xxxxxxxxxxxxxxxx > >> https://urldefense.proofpoint.com/v2/url?u=https-3A__mailman.alsa-2Dproject.org_mailman_listinfo_alsa-2Ddevel&d=DwIBAg&c=aUq983L2pue2FqKFoP6PGHMJQyoJ7kl3s3GZ-_haXqY&r=g7GAQENVXx_RQdyXHInPMg&m=i_0S359hFIVqNgv3fR5_MNzDOHP99trdXszZ-FMiQEE&s=RxPHxKfI3v6Fkh7qzKjq8sNi-5QMoY8XfyMDSquA38o&e= > > _______________________________________________ > Alsa-devel mailing list > Alsa-devel@xxxxxxxxxxxxxxxx > https://mailman.alsa-project.org/mailman/listinfo/alsa-devel _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
