Re: [PATCH v3 4/4] gpio: brcmstb: support wakeup from S5 cold boot

Linus Walleij
2015-07-13T13:03:13Z

On Thu, Jun 18, 2015 at 3:00 AM, Gregory Fong <gregory.0xf0@gmail.com> wrote:

> For wake from S5, we need to:
> - register a reboot handler
> - set wakeup capability before requesting IRQ so wakeup count is
> incremented
> - mask all GPIO IRQs and clear any pending interrupts during driver
> probe to since no driver will yet be registered to handle any IRQs
> carried over from boot at that time, and it's possible that the
> booted kernel does not request the same IRQ anyway.
>
> This means that /sys/.../power/wakeup_count is valid at boot time, and
> we can properly account for S5 wakeup stats. e.g.:
>
> ### After waking from S5 from a GPIO key
> # cat /sys/bus/platform/drivers/brcmstb-gpio/f04172c0.gpio/power/wakeup
> enabled
> # cat /sys/bus/platform/drivers/brcmstb-gpio/f04172c0.gpio/power/wakeup_count
> 1
>
> Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com>

(...)
> -static int brcmstb_gpio_irq_set_wake(struct irq_data *d, unsigned int enable)
> +static int __brcmstb_gpio_irq_set_wake(struct brcmstb_gpio_priv *priv,
> + unsigned int enable)
> {
> - struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
> - struct brcmstb_gpio_priv *priv = brcmstb_gpio_gc_to_priv(gc);
> int ret = 0;

I don't usually like to refactor code with __foo wrapper functions with
underscores or double underscores in front of them.

Is it possible to give this a more unique name?

> + /*
> + * Mask all interrupts by default, since wakeup interrupts may
> + * be retained from S5 cold boot
> + */
> + bank->bgc.write_reg(reg_base + GIO_MASK(bank->id), 0);

Aha I see, that's some clever code, nice.

Yours,
Linus Walleij