Re: [PATCH v2 0/3] input: rmi4: Regulator supply support

[Andrew Duggan]

On 05/13/2016 03:29 PM, Bjorn Andersson wrote:
> On Thu 12 May 17:52 PDT 2016, Andrew Duggan wrote:
>
> > On 05/11/2016 08:05 PM, Bjorn Andersson wrote:
> > > On Wed 11 May 16:30 PDT 2016, Andrew Duggan wrote:
> > >
> > > > Hi Bjorn,
> > > >
> > > > On 05/10/2016 08:49 AM, Bjorn Andersson wrote:
> > > [..]
> > > > > So either we duplicate the regulator support in spi/i2c or we make them
> > > > > optional in the core driver. Sounds like you prefer the prior, i.e. v1
> > > > > of my patch.
> > > > Yes, after all this I think it makes sense to put regulator support in the
> > > > spi/i2c transports like in your v1 patch. I essentially duplicated the irq
> > > > handling code in both transports so I would be ok with duplicating regulator
> > > > support too. It doesn't seem like that much code. But, if this is too much
> > > > duplication we could create some sort of common file and put the common irq
> > > > and regulator support functions which could be called in the transports.
> > > > Similar to how rmi_2d_sensor.c defines some common functions shared between
> > > > rmi_f11 and rmi_f12.
> > > Sounds reasonable, I'm okay with this. Did you have any comments on the
> > > implementation I had in v1?
> > I tested on a device which has an always on regulators so I didn't add
> > anything to device tree for the device. But, it returned 0 when it didn't
> > find anything which seems to be the correct behavior. Is there an easy way
> > to avoid sleeping for 10ms when there are no regulators? Maybe check if both
> > the supplies .consumer pointer is null?
> I did look at this as well, but unfortunately the regulators does not
> come back as NULL, but rather as dummy regulators.
>
> The delay matches Tpowerup (iirc) from the data sheet, which I assume is
> firmware/hardware dependant. Should we provide a knob for that and
> default the sleep to 0ms?

Making  the default 0 and then setting an appropriate time out for 
devices which need it sounds like a good idea to me.

Thanks,
Andrew

> Regards,
> Bjorn