On 11/16/2013 03:02 AM, Mark Brown wrote: > On Fri, Nov 15, 2013 at 01:54:12PM -0700, Stephen Warren wrote: >> From: Stephen Warren <swarren@xxxxxxxxxx> >> >> Call pm_runtime_get_sync() before all register accesses; the HW requires >> clocks to be running when accessing registers. >> >> This hasn't been needed to date, since all register IO was performed >> while playback was active, and hence the ASoC core had already called >> pm_runtime_get(). However, an imminent future commit will allocate and >> set up the FIFOs and routing during probe(), when that "protection" >> won't be in place. > > Acked-by: Mark Brown <broonie@xxxxxxxxxx> > > However should we fix this at the regmap level in the same way that we > do for clocks? That would need to be using _put_autosuspend() to avoid > being horrific. I did wonder about that, but it seemed like rather a lot of overhead? > Or alternatively should the driver be making the device > cache only when runtime PM is disabled? The regmap is already cache-only when runtime-suspended. However the registers don't get flushed during resume. I suppose that would require only adding one extra call to the PM resume function? For some reason, my gut prefers this current solution, but I could be persuaded. -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
