[PATCH 1/2] pinctrl: pimux: Add support to save and restore HW register

From: Prathamesh Shete
Date: Tue Aug 31 2021 - 01:29:14 EST


From: Laxman Dewangan <ldewangan@xxxxxxxxxx>

Add support to save and restore the pincontrol HW register
for GPIO mode configurations. This helps in changing the
pin configure only during suspend and restore in resume.

Signed-off-by: Laxman Dewangan <ldewangan@xxxxxxxxxx>
Signed-off-by: pshete <pshete@xxxxxxxxxx>
---
drivers/pinctrl/pinmux.c | 24 ++++++++++++++++++++++++
drivers/pinctrl/pinmux.h | 18 ++++++++++++++++++
include/linux/pinctrl/pinmux.h | 9 +++++++++
3 files changed, 51 insertions(+)

diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c
index 6cdbd9ccf2f0..66fc0ca22623 100644
--- a/drivers/pinctrl/pinmux.c
+++ b/drivers/pinctrl/pinmux.c
@@ -317,6 +317,30 @@ int pinmux_gpio_direction(struct pinctrl_dev *pctldev,
return ret;
}

+int pinmux_gpio_save_config(struct pinctrl_dev *pctldev,
+ struct pinctrl_gpio_range *range,
+ unsigned pin)
+{
+ const struct pinmux_ops *ops = pctldev->desc->pmxops;
+
+ if (ops->gpio_save_config)
+ return ops->gpio_save_config(pctldev, range, pin);
+
+ return 0;
+}
+
+int pinmux_gpio_restore_config(struct pinctrl_dev *pctldev,
+ struct pinctrl_gpio_range *range,
+ unsigned pin)
+{
+ const struct pinmux_ops *ops = pctldev->desc->pmxops;
+
+ if (ops->gpio_restore_config)
+ return ops->gpio_restore_config(pctldev, range, pin);
+
+ return 0;
+}
+
static int pinmux_func_name_to_selector(struct pinctrl_dev *pctldev,
const char *function)
{
diff --git a/drivers/pinctrl/pinmux.h b/drivers/pinctrl/pinmux.h
index 78c3a31be882..425c31a0115b 100644
--- a/drivers/pinctrl/pinmux.h
+++ b/drivers/pinctrl/pinmux.h
@@ -31,6 +31,12 @@ int pinmux_map_to_setting(const struct pinctrl_map *map,
void pinmux_free_setting(const struct pinctrl_setting *setting);
int pinmux_enable_setting(const struct pinctrl_setting *setting);
void pinmux_disable_setting(const struct pinctrl_setting *setting);
+int pinmux_gpio_save_config(struct pinctrl_dev *pctldev,
+ struct pinctrl_gpio_range *range,
+ unsigned pin);
+int pinmux_gpio_restore_config(struct pinctrl_dev *pctldev,
+ struct pinctrl_gpio_range *range,
+ unsigned pin);

#else

@@ -89,6 +95,18 @@ static inline void pinmux_disable_setting(const struct pinctrl_setting *setting)
{
}

+int pinmux_gpio_save_config(struct pinctrl_dev *pctldev,
+ struct pinctrl_gpio_range *range,
+ unsigned pin)
+{
+ return 0;
+}
+int pinmux_gpio_restore_config(struct pinctrl_dev *pctldev,
+ struct pinctrl_gpio_range *range,
+ unsigned pin)
+{
+ return 0;
+}
#endif

#if defined(CONFIG_PINMUX) && defined(CONFIG_DEBUG_FS)
diff --git a/include/linux/pinctrl/pinmux.h b/include/linux/pinctrl/pinmux.h
index 9a647fa5c8f1..cca87586d8c1 100644
--- a/include/linux/pinctrl/pinmux.h
+++ b/include/linux/pinctrl/pinmux.h
@@ -53,6 +53,8 @@ struct pinctrl_dev;
* depending on whether the GPIO is configured as input or output,
* a direction selector function may be implemented as a backing
* to the GPIO controllers that need pin muxing.
+ * @gpio_save_config: Save the GPIo configurations.
+ * @gpio_restore_config: Restore GPIO configurations.
* @strict: do not allow simultaneous use of the same pin for GPIO and another
* function. Check both gpio_owner and mux_owner strictly before approving
* the pin request.
@@ -79,6 +81,13 @@ struct pinmux_ops {
struct pinctrl_gpio_range *range,
unsigned offset,
bool input);
+ int (*gpio_save_config) (struct pinctrl_dev *pctldev,
+ struct pinctrl_gpio_range *range,
+ unsigned offset);
+ int (*gpio_restore_config) (struct pinctrl_dev *pctldev,
+ struct pinctrl_gpio_range *range,
+ unsigned offset);
+
bool strict;
};

--
2.17.1