Re: [PATCH v2 5/7] mfd: Add RTL8231 core device

[Sander Vanheule <sander@xxxxxxxxxxxxx>]

Hi Andy,

I forgot to address one of your questions, so here's a short follow up.

On Tue, 2021-05-18 at 00:18 +0300, Andy Shevchenko wrote:
> On Mon, May 17, 2021 at 10:28 PM Sander Vanheule <sander@xxxxxxxxxxxxx> wrote:
> > +       err = regmap_read(map, RTL8231_REG_FUNC1, &v);
> 
> > +       ready_code = FIELD_GET(RTL8231_FUNC1_READY_CODE_MASK, v);
> 
> If we got an error why we need a read_core, what for?

The chip has a static 5-bit field in register 0x01, called READY_CODE according
to the datasheet. If a device is present, and a read from register 0x01
succeeds, I still check that this field has the correct value. For the RTL8231,
it should return 0x37. If this isn't the case, I assume this isn't an RTL8231,
so the driver probe stops and returns an error value.

Best,
Sander