Re: [PATCH v1 1/5] gpio: max77620: Initialize interrupts state

From: Andy Shevchenko
Date: Wed Jul 08 2020 - 04:51:24 EST


On Wed, Jul 8, 2020 at 11:29 AM Dmitry Osipenko <digetx@xxxxxxxxx> wrote:
>
> I noticed on Nexus 7 that after rebooting from downstream kernel to
> upstream, the GPIO interrupt is triggering non-stop despite of interrupts
> being disabled for all of GPIOs. This happens because Nexus 7 uses a
> soft-reboot, meaning that bootloader should take care of resetting
> hardware, but bootloader doesn't do it well. In a result, GPIO interrupt
> may be left ON at a boot time. Let's mask all GPIO interrupts at the
> driver's probe time in order to resolve the issue.

...

> + err = regmap_update_bits(mgpio->rmap, GPIO_REG_ADDR(i),
> + MAX77620_CNFG_GPIO_INT_MASK, 0);
> + if (err < 0)

Does ' < 0' meaningful here?

> + dev_err(mgpio->dev, "failed to disable interrupt: %d\n",
> + err);

One line.

...

> + max77620_gpio_initialize(mgpio);

I guess we have special callback for that, i.e.
https://elixir.bootlin.com/linux/v5.8-rc3/C/ident/init_hw.


--
With Best Regards,
Andy Shevchenko