Re: [PATCH 4.13 015/109] pinctrl/amd: save pin registers over suspend/resume

[Petr Mladek]

On Sun 2017-09-24 22:32:36, Greg Kroah-Hartman wrote:
> 4.13-stable review patch.  If anyone has any objections, please let me know.
> 
> ------------------
> 
> From: Daniel Drake <drake@xxxxxxxxxxxx>
> 
> commit 79d2c8bede2c93f9432d7da0bc2f76a195c90fc0 upstream.
> 
> The touchpad in the Asus laptop models X505BA/BP and X542BA/BP is
> unresponsive after suspend/resume. The following error appears during
> resume:
> 
>   i2c_hid i2c-ELAN1300:00: failed to reset device.
> 
> The problem here is that i2c_hid does not notice the interrupt being
> generated at this point, because the GPIO is no longer configured
> for interrupts.
> 
> Fix this by saving pinctrl-amd pin registers during suspend and
> restoring them at resume time.
> 
> Based on code from pinctrl-intel.
> 
> Signed-off-by: Daniel Drake <drake@xxxxxxxxxxxx>
> Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> 
> --- a/drivers/pinctrl/pinctrl-amd.c
> +++ b/drivers/pinctrl/pinctrl-amd.c
> @@ -725,6 +726,69 @@ static const struct pinconf_ops amd_pinc
>  	.pin_config_group_set = amd_pinconf_group_set,
>  };
>  
> +#ifdef CONFIG_PM_SLEEP
> +static bool amd_gpio_should_save(struct amd_gpio *gpio_dev, unsigned int pin)
> +{
> +	const struct pin_desc *pd = pin_desc_get(gpio_dev->pctrl, pin);
> +
> +	if (!pd)
> +		return false;
> +
> +	/*
> +	 * Only restore the pin if it is actually in use by the kernel (or
> +	 * by userspace).
> +	 */
> +	if (pd->mux_owner || pd->gpio_owner ||

This code causes a compilation error in the current Linus' tree
(4.14-rc2+). I guess that the same problem will be also in
older trees.

IMHO, we need to select CONFIG_PINMUX for when CONFIG_PINCTRL_AMD
is selected. The following patch helped here: