pinctrl: rockchip: save and restore gpio6_c6 pinmux in suspend/resume

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.

Signed-off-by: Chris Zhong <zyw@rock-chips.com>
Tested-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

1 files changed, 29 insertions, 1 deletions

diff --git a/drivers/pinctrl/pinctrl-rockchip.c b/drivers/pinctrl/pinctrl-rockchip.c
index 28b12187c2c1..40970c305dd0 100644
--- a/drivers/pinctrl/pinctrl-rockchip.c
+++ b/drivers/pinctrl/pinctrl-rockchip.c
@@ -1796,16 +1796,44 @@ 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);
 }