[PATCH v5 2/6] pinctrl: rockchip: save and restore gpio6_c6 pinmux in suspend/resume

[Heiko Stübner]

Am Montag, 27. Oktober 2014, 21:47:26 schrieb Chris Zhong:
> Save and restore the gpio6_c6 pinmux setting, since Maskrom of RK3288
> would modify it to sdmmc0_det, so it need to be restored to the correct
> setting after resume from Maskrom.

Does the maskrom only touch the iomux or also stuff like pull-bias or drive 
strength for this pin?

Also could you please look up if the maskrom on rk3066a and rk3188 does 
something similar. While not strictly necessary for this patch, I'd like the 
driver to not diverge in functionality for to long.


Otherwise it looks fine for the time being.

Tested-by: Heiko Stuebner <heiko at sntech.de>
Reviewed-by: Heiko Stuebner <heiko at sntech.de>


> 
> Signed-off-by: Chris Zhong <zyw at rock-chips.com>
> 
> Reviewed-by: Doug Anderson <dianders at chromium.org>
> Tested-by: Doug Anderson <dianders at chromium.org>
> ---
> 
> Changes in v5:
> - add pinctrl_force_default() in the error case
> 
> Changes in v4: None
> Changes in v3: None
> Changes in v2: None
> 
>  drivers/pinctrl/pinctrl-rockchip.c |   30 +++++++++++++++++++++++++++++-
>  1 file changed, 29 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pinctrl/pinctrl-rockchip.c
> b/drivers/pinctrl/pinctrl-rockchip.c index 172ad1d..49ca40c 100644
> --- a/drivers/pinctrl/pinctrl-rockchip.c
> +++ b/drivers/pinctrl/pinctrl-rockchip.c
> @@ -1770,16 +1770,44 @@ static struct rockchip_pin_ctrl
> *rockchip_pinctrl_get_soc_data( return ctrl;
>  }
> 
> +#define RK3288_GRF_GPIO6C_IOMUX		0x64
> +#define GPIO6C6_SEL_WRITE_ENABLE	BIT(28)
> +
> +static u32 rk3288_grf_gpio6c_iomux;
> +
>  static int __maybe_unused rockchip_pinctrl_suspend(struct device *dev)
>  {
>  	struct rockchip_pinctrl *info = dev_get_drvdata(dev);
> +	int ret = pinctrl_force_sleep(info->pctl_dev);
> +
> +	if (ret)
> +		return ret;
> +
> +	/*
> +	 * RK3288 GPIO6_C6 mux would be modified by Maskrom when resume, so save
> +	 * the setting here, and restore it at resume.
> +	 */
> +	if (info->ctrl->type == RK3288) {
> +		ret = regmap_read(info->regmap_base, RK3288_GRF_GPIO6C_IOMUX,
> +				  &rk3288_grf_gpio6c_iomux);
> +		if (ret) {
> +			pinctrl_force_default(info->pctl_dev);
> +			return ret;
> +		}
> +	}
> 
> -	return pinctrl_force_sleep(info->pctl_dev);
> +	return 0;
>  }
> 
>  static int __maybe_unused rockchip_pinctrl_resume(struct device *dev)
>  {
>  	struct rockchip_pinctrl *info = dev_get_drvdata(dev);
> +	int ret = regmap_write(info->regmap_base, RK3288_GRF_GPIO6C_IOMUX,
> +			       rk3288_grf_gpio6c_iomux |
> +			       GPIO6C6_SEL_WRITE_ENABLE);
> +
> +	if (ret)
> +		return ret;
> 
>  	return pinctrl_force_default(info->pctl_dev);
>  }