Re: [PATCH] mfd: qcom-spmi-pmic: Add support for more chips versions

From: Ivan T. Ivanov
Date: Wed Nov 12 2014 - 04:12:16 EST



On Tue, 2014-11-11 at 12:27 -0800, Courtney Cavin wrote:
> On Fri, Nov 07, 2014 at 04:40:52PM +0100, Ivan T. Ivanov wrote:
> >
> > Forgot to add. PMIC subtype and version are used also in charger and BMS
> > drivers to workaround hardware issues.
>
> All of the blocks on the PM8x41 series have their own version numbers.
> There's no need to look at the chip revision.

I am suspecting that, for whatever the reason is, after updates inside blocks,
the PMIC chip revisions update was made instead of blocks own version update.

>
> In fact, the SMBB (charger) documentation (80-NA555-12) specifically

It would be nice if I had this document :-).

> refers to the SMBB_MISC block revision registers as the method for
> determining the hardware version. The "qpnp-charger" SMBB driver in the
> CAF 3.4 & 3.10 trees utilizes block specific revision numbers, as do the
> "qpnp-bms" BMS driver, the "qpnp-adc-current" IADC driver, and the
> "qpnp-adc-voltage" VADC driver.

Hm, they read its own block revision, but they are using PMIC chip revision
for workaround decisions. What could be the reason for this?

>
> The revision of the PMIC itself should be completely irrelevant to any
> of the software interfacing with it.
>

It will be really nice if this is the case, but I am afraid it is not.

Regards,
Ivan



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