On 15/09/2020 16:14:01+0200, Miquel Raynal wrote: > Mark Brown <broonie@xxxxxxxxxx> wrote on Tue, 15 Sep 2020 15:10:25 > +0100: > > > On Tue, Sep 15, 2020 at 03:02:07PM +0200, Alexandre Belloni wrote: > > > On 15/09/2020 12:50:34+0100, Mark Brown wrote: > > > > On Tue, Sep 15, 2020 at 10:26:02AM +0200, Alexandre Belloni wrote: > > > > > On 11/09/2020 19:31:40+0200, Miquel Raynal wrote: > > > > > > > > + /* > > > > > > + * Enable the fast charging feature and ensure the needed 40ms ellapsed > > > > > > + * before using the analog circuits. > > > > > > + */ > > > > > > + snd_soc_component_write(component, AIC32X4_REFPOWERUP, > > > > > > + AIC32X4_REFPOWERUP_40MS); > > > > > > + msleep(40); > > > > > > + > > > > > > > Maybe the actual REFPOWERUP value could be exposed as a control so > > > > > userspace has a way to set the policy? > > > > > > We very rarely do this, there's not usially anything > > > > > Could you suggest something then? This mainly changes the power > > > codec power consumption. I guess people will want to trade latency > > > for less consumption. > > > > Is it increasing steady state power consumption or is it just drawing > > more power during the ramp (ie, peak current consumption is bigger)? > > Usually this is trading off clean ramps for fast ramps rather than > > affecting steady state. If it's affecting steady state a control seems > > sensible. > > Indeed, it is just affecting the ramp (peak current is bigger). > However, forcing powerup at probe time versus at play time means that you consume power even when not playing audio. -- Alexandre Belloni, Bootlin Embedded Linux and Kernel engineering https://bootlin.com
