Re: [PATCH 03/13] mfd: pm8008: deassert reset on probe

From: Johan Hovold
Date: Tue May 07 2024 - 11:15:47 EST


On Mon, May 06, 2024 at 09:57:07PM +0300, Andy Shevchenko wrote:
> Mon, May 06, 2024 at 05:08:20PM +0200, Johan Hovold kirjoitti:
> > Request and deassert any (optional) reset gpio during probe in case it
> > has been left asserted by the boot firmware.
> >
> > Note the reset line is not asserted to avoid reverting to the default
> > I2C address in case the firmware has configured an alternate address.
>
> ...
>
> > + reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
> > + if (IS_ERR(reset))
> > + return PTR_ERR(reset);
>
> Shouldn't you wait a bit to make chip settle down?

Yeah, probably. I actually asserted reset here for a while (e.g. to
reset the address), but didn't have to use a post-reset delay then.

I'll see if I can find someone with access to a datasheet or maybe add
some small delay here anyway.

Johan