[PATCH v2 4/6] pinctrl: cs42l43: Add support for the cs42l43

[Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>]

The CS42L43 is an audio CODEC with integrated MIPI SoundWire interface
(Version 1.2.1 compliant), I2C, SPI, and I2S/TDM interfaces designed
for portable applications. It provides a high dynamic range, stereo
DAC for headphone output, two integrated Class D amplifiers for
loudspeakers, and two ADCs for wired headset microphone input or
stereo line input. PDM inputs are provided for digital microphones.

Add a basic pinctrl driver which supports driver strength for the
various pins, gpios, and pinmux for the 2 multi-function pins.

Signed-off-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>
---

Changes since v1:
 - Tidy up code around device_set_node
 - Use same node for GPIO and Pinctrl in binding
 - Re-order include files
 - Move gpio_chip to start of the private struct
 - Use PINCTRL_PINGROUP/PINFUNCTION
 - Add/remove a bunch of commas to arrays
 - Change BUILD_BUG_ONs to static_asserts
 - Use a ternary for value setting in cs42l43_pin_set_mux
 - Remove uneccesary else
 - Use str_on_off
 - Use post increment operator rather than pre inc
 - Use devm_pm_runtime_enable
 - Use dev_err_probe
 - Switch to using a platform_device_id table
 - Use the callback for adding pin ranges

Thanks,
Charles

 MAINTAINERS                              |   1 +
 drivers/pinctrl/cirrus/Kconfig           |  11 +
 drivers/pinctrl/cirrus/Makefile          |   2 +
 drivers/pinctrl/cirrus/pinctrl-cs42l43.c | 609 +++++++++++++++++++++++
 4 files changed, 623 insertions(+)
 create mode 100644 drivers/pinctrl/cirrus/pinctrl-cs42l43.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 8d2076941ff36..ed26f63087342 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4929,6 +4929,7 @@ S:	Maintained
 F:	Documentation/devicetree/bindings/mfd/cirrus,cs*
 F:	Documentation/devicetree/bindings/sound/cirrus,cs*
 F:	drivers/mfd/cs42l43*
+F:	drivers/pinctrl/cirrus/pinctrl-cs42l43*
 F:	include/dt-bindings/sound/cs*
 F:	include/linux/mfd/cs42l43*
 F:	include/sound/cs*
diff --git a/drivers/pinctrl/cirrus/Kconfig b/drivers/pinctrl/cirrus/Kconfig
index 530426a74f751..d6318cb57aff2 100644
--- a/drivers/pinctrl/cirrus/Kconfig
+++ b/drivers/pinctrl/cirrus/Kconfig
@@ -1,4 +1,15 @@
 # SPDX-License-Identifier: GPL-2.0-only
+config PINCTRL_CS42L43
+	tristate "Cirrus Logic CS42L43 Pinctrl Driver"
+	depends on MFD_CS42L43
+	select GPIOLIB
+	select PINMUX
+	select PINCONF
+	select GENERIC_PINCONF
+	help
+	  Select this to support the GPIO/Pinctrl functions of the Cirrus
+	  Logic CS42L43 PC CODEC.
+
 config PINCTRL_LOCHNAGAR
 	tristate "Cirrus Logic Lochnagar pinctrl driver"
 	depends on MFD_LOCHNAGAR
diff --git a/drivers/pinctrl/cirrus/Makefile b/drivers/pinctrl/cirrus/Makefile
index a484518c840e3..9b618d7669071 100644
--- a/drivers/pinctrl/cirrus/Makefile
+++ b/drivers/pinctrl/cirrus/Makefile
@@ -1,5 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0-only
 # Cirrus Logic pinctrl drivers
+obj-$(CONFIG_PINCTRL_CS42L43)	+= pinctrl-cs42l43.o
+
 obj-$(CONFIG_PINCTRL_LOCHNAGAR)	+= pinctrl-lochnagar.o
 
 pinctrl-madera-objs		:= pinctrl-madera-core.o
diff --git a/drivers/pinctrl/cirrus/pinctrl-cs42l43.c b/drivers/pinctrl/cirrus/pinctrl-cs42l43.c
new file mode 100644
index 0000000000000..c096463184195
--- /dev/null
+++ b/drivers/pinctrl/cirrus/pinctrl-cs42l43.c
@@ -0,0 +1,609 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// CS42L43 Pinctrl and GPIO driver
+//
+// Copyright (c) 2023 Cirrus Logic, Inc. and
+//                    Cirrus Logic International Semiconductor Ltd.
+
+#include <linux/bits.h>
+#include <linux/build_bug.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/gpio/driver.h>
+#include <linux/mfd/cs42l43.h>
+#include <linux/mfd/cs42l43-regs.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/string_helpers.h>
+
+#include <linux/pinctrl/consumer.h>
+#include <linux/pinctrl/pinctrl.h>
+#include <linux/pinctrl/pinconf.h>
+#include <linux/pinctrl/pinconf-generic.h>
+#include <linux/pinctrl/pinmux.h>
+
+#include "../pinctrl-utils.h"
+
+#define CS42L43_NUM_GPIOS 3
+
+struct cs42l43_pin {
+	struct gpio_chip gpio_chip;
+
+	struct device *dev;
+	struct regmap *regmap;
+	bool shutters_locked;
+};
+
+struct cs42l43_pin_data {
+	unsigned int reg;
+	unsigned int shift;
+	unsigned int mask;
+};
+
+#define CS42L43_PIN(_number, _name, _reg, _field) { \
+	.number = _number, .name = _name, \
+	.drv_data = &((struct cs42l43_pin_data){ \
+		.reg = CS42L43_##_reg, \
+		.shift = CS42L43_##_field##_DRV_SHIFT, \
+		.mask = CS42L43_##_field##_DRV_MASK, \
+	}), \
+}
+
+static const struct pinctrl_pin_desc cs42l43_pin_pins[] = {
+	CS42L43_PIN(0,	"gpio1",	DRV_CTRL4,	GPIO1),
+	CS42L43_PIN(1,	"gpio2",	DRV_CTRL4,	GPIO2),
+	CS42L43_PIN(2,	"gpio3",	DRV_CTRL4,	GPIO3),
+	CS42L43_PIN(3,	"asp_dout",	DRV_CTRL1,	ASP_DOUT),
+	CS42L43_PIN(4,	"asp_fsync",	DRV_CTRL1,	ASP_FSYNC),
+	CS42L43_PIN(5,	"asp_bclk",	DRV_CTRL1,	ASP_BCLK),
+	CS42L43_PIN(6,	"pdmout2_clk",	DRV_CTRL3,	PDMOUT2_CLK),
+	CS42L43_PIN(7,	"pdmout2_data",	DRV_CTRL3,	PDMOUT2_DATA),
+	CS42L43_PIN(8,	"pdmout1_clk",	DRV_CTRL3,	PDMOUT1_CLK),
+	CS42L43_PIN(9,	"pdmout1_data",	DRV_CTRL3,	PDMOUT1_DATA),
+	CS42L43_PIN(10,	"i2c_sda",	DRV_CTRL3,	I2C_SDA),
+	CS42L43_PIN(11,	"i2c_scl",	DRV_CTRL_5,	I2C_SCL),
+	CS42L43_PIN(12,	"spi_miso",	DRV_CTRL3,	SPI_MISO),
+	CS42L43_PIN(13,	"spi_sck",	DRV_CTRL_5,	SPI_SCK),
+	CS42L43_PIN(14,	"spi_ssb",	DRV_CTRL_5,	SPI_SSB),
+};
+
+static const unsigned int cs42l43_pin_gpio1_pins[] = { 0 };
+static const unsigned int cs42l43_pin_gpio2_pins[] = { 1 };
+static const unsigned int cs42l43_pin_gpio3_pins[] = { 2 };
+static const unsigned int cs42l43_pin_asp_pins[] = { 3, 4, 5 };
+static const unsigned int cs42l43_pin_pdmout2_pins[] = { 6, 7 };
+static const unsigned int cs42l43_pin_pdmout1_pins[] = { 8, 9 };
+static const unsigned int cs42l43_pin_i2c_pins[] = { 10, 11 };
+static const unsigned int cs42l43_pin_spi_pins[] = { 12, 13, 14 };
+
+#define CS42L43_PINGROUP(_name) \
+	PINCTRL_PINGROUP(#_name, cs42l43_pin_##_name##_pins, \
+			 ARRAY_SIZE(cs42l43_pin_##_name##_pins))
+
+static const struct pingroup cs42l43_pin_groups[] = {
+	CS42L43_PINGROUP(gpio1),
+	CS42L43_PINGROUP(gpio2),
+	CS42L43_PINGROUP(gpio3),
+	CS42L43_PINGROUP(asp),
+	CS42L43_PINGROUP(pdmout2),
+	CS42L43_PINGROUP(pdmout1),
+	CS42L43_PINGROUP(i2c),
+	CS42L43_PINGROUP(spi),
+};
+
+static int cs42l43_pin_get_groups_count(struct pinctrl_dev *pctldev)
+{
+	return ARRAY_SIZE(cs42l43_pin_groups);
+}
+
+static const char *cs42l43_pin_get_group_name(struct pinctrl_dev *pctldev,
+					      unsigned int group_idx)
+{
+	return cs42l43_pin_groups[group_idx].name;
+}
+
+static int cs42l43_pin_get_group_pins(struct pinctrl_dev *pctldev,
+				      unsigned int group_idx,
+				      const unsigned int **pins,
+				      unsigned int *num_pins)
+{
+	*pins = cs42l43_pin_groups[group_idx].pins;
+	*num_pins = cs42l43_pin_groups[group_idx].npins;
+
+	return 0;
+}
+
+static const struct pinctrl_ops cs42l43_pin_group_ops = {
+	.get_groups_count = cs42l43_pin_get_groups_count,
+	.get_group_name = cs42l43_pin_get_group_name,
+	.get_group_pins = cs42l43_pin_get_group_pins,
+#if IS_ENABLED(CONFIG_OF)
+	.dt_node_to_map = pinconf_generic_dt_node_to_map_all,
+	.dt_free_map = pinconf_generic_dt_free_map,
+#endif
+};
+
+enum cs42l43_pin_funcs {
+	CS42L43_FUNC_GPIO,
+	CS42L43_FUNC_SPDIF,
+	CS42L43_FUNC_IRQ,
+	CS42L43_FUNC_MIC_SHT,
+	CS42L43_FUNC_SPK_SHT,
+	CS42L43_FUNC_MAX
+};
+
+static const char * const cs42l43_pin_funcs[] = {
+	"gpio", "spdif", "irq", "mic-shutter", "spk-shutter",
+};
+
+static const char * const cs42l43_pin_gpio_groups[] = { "gpio1", "gpio3" };
+static const char * const cs42l43_pin_spdif_groups[] = { "gpio3" };
+static const char * const cs42l43_pin_irq_groups[] = { "gpio1" };
+static const char * const cs42l43_pin_shutter_groups[] = { "gpio1", "gpio2", "gpio3" };
+
+static const struct pinfunction cs42l43_pin_func_groups[] = {
+	PINCTRL_PINFUNCTION("gpio", cs42l43_pin_gpio_groups,
+			    ARRAY_SIZE(cs42l43_pin_gpio_groups)),
+	PINCTRL_PINFUNCTION("spdif", cs42l43_pin_spdif_groups,
+			    ARRAY_SIZE(cs42l43_pin_spdif_groups)),
+	PINCTRL_PINFUNCTION("irq",  cs42l43_pin_irq_groups,
+			    ARRAY_SIZE(cs42l43_pin_irq_groups)),
+	PINCTRL_PINFUNCTION("mic-shutter", cs42l43_pin_shutter_groups,
+			    ARRAY_SIZE(cs42l43_pin_shutter_groups)),
+	PINCTRL_PINFUNCTION("spk-shutter", cs42l43_pin_shutter_groups,
+			    ARRAY_SIZE(cs42l43_pin_shutter_groups)),
+};
+
+static_assert(ARRAY_SIZE(cs42l43_pin_funcs) == CS42L43_FUNC_MAX);
+static_assert(ARRAY_SIZE(cs42l43_pin_func_groups) == CS42L43_FUNC_MAX);
+
+static int cs42l43_pin_get_func_count(struct pinctrl_dev *pctldev)
+{
+	return ARRAY_SIZE(cs42l43_pin_funcs);
+}
+
+static const char *cs42l43_pin_get_func_name(struct pinctrl_dev *pctldev,
+					     unsigned int func_idx)
+{
+	return cs42l43_pin_funcs[func_idx];
+}
+
+static int cs42l43_pin_get_func_groups(struct pinctrl_dev *pctldev,
+				       unsigned int func_idx,
+				       const char * const **groups,
+				       unsigned int * const num_groups)
+{
+	*groups = cs42l43_pin_func_groups[func_idx].groups;
+	*num_groups = cs42l43_pin_func_groups[func_idx].ngroups;
+
+	return 0;
+}
+
+static int cs42l43_pin_set_mux(struct pinctrl_dev *pctldev,
+			       unsigned int func_idx, unsigned int group_idx)
+{
+	struct cs42l43_pin *priv = pinctrl_dev_get_drvdata(pctldev);
+	unsigned int reg, mask, val;
+
+	dev_dbg(priv->dev, "Setting %s to %s\n",
+		cs42l43_pin_groups[group_idx].name, cs42l43_pin_funcs[func_idx]);
+
+	switch (func_idx) {
+	case CS42L43_FUNC_MIC_SHT:
+		reg = CS42L43_SHUTTER_CONTROL;
+		mask = CS42L43_MIC_SHUTTER_CFG_MASK;
+		val = 0x2 << (group_idx + CS42L43_MIC_SHUTTER_CFG_SHIFT);
+		break;
+	case CS42L43_FUNC_SPK_SHT:
+		reg = CS42L43_SHUTTER_CONTROL;
+		mask = CS42L43_SPK_SHUTTER_CFG_MASK;
+		val = 0x2 << (group_idx + CS42L43_SPK_SHUTTER_CFG_SHIFT);
+		break;
+	default:
+		reg = CS42L43_GPIO_FN_SEL;
+		mask = BIT(group_idx + CS42L43_GPIO1_FN_SEL_SHIFT);
+		val = (func_idx == CS42L43_FUNC_GPIO) ?
+				(0x1 << (group_idx + CS42L43_GPIO1_FN_SEL_SHIFT)) : 0;
+		break;
+	}
+
+	if (priv->shutters_locked && reg == CS42L43_SHUTTER_CONTROL) {
+		dev_err(priv->dev, "Shutter configuration not available\n");
+		return -EPERM;
+	}
+
+	return regmap_update_bits(priv->regmap, reg, mask, val);
+}
+
+static int cs42l43_gpio_set_direction(struct pinctrl_dev *pctldev,
+				      struct pinctrl_gpio_range *range,
+				      unsigned int offset, bool input)
+{
+	struct cs42l43_pin *priv = pinctrl_dev_get_drvdata(pctldev);
+	unsigned int shift = offset + CS42L43_GPIO1_DIR_SHIFT;
+	int ret;
+
+	dev_dbg(priv->dev, "Setting gpio%d to %s\n",
+		offset + 1, input ? "input" : "output");
+
+	ret = pm_runtime_resume_and_get(priv->dev);
+	if (ret) {
+		dev_err(priv->dev, "Failed to resume for direction: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_update_bits(priv->regmap, CS42L43_GPIO_CTRL1,
+				 BIT(shift), !!input << shift);
+	if (ret)
+		dev_err(priv->dev, "Failed to set gpio%d direction: %d\n",
+			offset + 1, ret);
+
+	pm_runtime_put(priv->dev);
+
+	return ret;
+}
+
+static int cs42l43_gpio_request_enable(struct pinctrl_dev *pctldev,
+				       struct pinctrl_gpio_range *range,
+				       unsigned int offset)
+{
+	return cs42l43_pin_set_mux(pctldev, 0, offset);
+}
+
+static void cs42l43_gpio_disable_free(struct pinctrl_dev *pctldev,
+				      struct pinctrl_gpio_range *range,
+				      unsigned int offset)
+{
+	cs42l43_gpio_set_direction(pctldev, range, offset, true);
+}
+
+static const struct pinmux_ops cs42l43_pin_mux_ops = {
+	.get_functions_count	= cs42l43_pin_get_func_count,
+	.get_function_name	= cs42l43_pin_get_func_name,
+	.get_function_groups	= cs42l43_pin_get_func_groups,
+
+	.set_mux		= cs42l43_pin_set_mux,
+
+	.gpio_request_enable	= cs42l43_gpio_request_enable,
+	.gpio_disable_free	= cs42l43_gpio_disable_free,
+	.gpio_set_direction	= cs42l43_gpio_set_direction,
+
+	.strict			= true,
+};
+
+static const unsigned int cs42l43_pin_drv_str_ma[] = { 1, 2, 4, 8, 9, 10, 12, 16 };
+
+static inline int cs42l43_pin_get_drv_str(struct cs42l43_pin *priv, unsigned int pin)
+{
+	const struct cs42l43_pin_data *pdat = cs42l43_pin_pins[pin].drv_data;
+	unsigned int val;
+	int ret;
+
+	ret = regmap_read(priv->regmap, pdat->reg, &val);
+	if (ret)
+		return ret;
+
+	return cs42l43_pin_drv_str_ma[(val & pdat->mask) >> pdat->shift];
+}
+
+static inline int cs42l43_pin_set_drv_str(struct cs42l43_pin *priv, unsigned int pin,
+					  unsigned int ma)
+{
+	const struct cs42l43_pin_data *pdat = cs42l43_pin_pins[pin].drv_data;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(cs42l43_pin_drv_str_ma); i++) {
+		if (ma == cs42l43_pin_drv_str_ma[i]) {
+			if ((i << pdat->shift) > pdat->mask)
+				goto err;
+
+			dev_dbg(priv->dev, "Set drive strength for %s to %d mA\n",
+				cs42l43_pin_pins[pin].name, ma);
+
+			return regmap_update_bits(priv->regmap, pdat->reg,
+						  pdat->mask, i << pdat->shift);
+		}
+	}
+
+err:
+	dev_err(priv->dev, "Invalid drive strength for %s: %d mA\n",
+		cs42l43_pin_pins[pin].name, ma);
+	return -EINVAL;
+}
+
+static inline int cs42l43_pin_get_db(struct cs42l43_pin *priv, unsigned int pin)
+{
+	unsigned int val;
+	int ret;
+
+	if (pin >= CS42L43_NUM_GPIOS)
+		return -ENOTSUPP;
+
+	ret = regmap_read(priv->regmap, CS42L43_GPIO_CTRL2, &val);
+	if (ret)
+		return ret;
+
+	if (val & (CS42L43_GPIO1_DEGLITCH_BYP_MASK << pin))
+		return 0;
+
+	return 85; // Debounce is roughly 85uS
+}
+
+static inline int cs42l43_pin_set_db(struct cs42l43_pin *priv, unsigned int pin,
+				     unsigned int us)
+{
+	if (pin >= CS42L43_NUM_GPIOS)
+		return -ENOTSUPP;
+
+	dev_dbg(priv->dev, "Set debounce %s for %s\n",
+		str_on_off(us), cs42l43_pin_pins[pin].name);
+
+	return regmap_update_bits(priv->regmap, CS42L43_GPIO_CTRL2,
+				  CS42L43_GPIO1_DEGLITCH_BYP_MASK << pin,
+				  !!us << pin);
+}
+
+static int cs42l43_pin_config_get(struct pinctrl_dev *pctldev,
+				  unsigned int pin, unsigned long *config)
+{
+	struct cs42l43_pin *priv = pinctrl_dev_get_drvdata(pctldev);
+	unsigned int param = pinconf_to_config_param(*config);
+	int ret;
+
+	switch (param) {
+	case PIN_CONFIG_DRIVE_STRENGTH:
+		ret = cs42l43_pin_get_drv_str(priv, pin);
+		if (ret < 0)
+			return ret;
+		break;
+	case PIN_CONFIG_INPUT_DEBOUNCE:
+		ret = cs42l43_pin_get_db(priv, pin);
+		if (ret < 0)
+			return ret;
+		break;
+	default:
+		return -ENOTSUPP;
+	}
+
+	*config = pinconf_to_config_packed(param, ret);
+
+	return 0;
+}
+
+static int cs42l43_pin_config_set(struct pinctrl_dev *pctldev, unsigned int pin,
+				  unsigned long *configs, unsigned int num_configs)
+{
+	struct cs42l43_pin *priv = pinctrl_dev_get_drvdata(pctldev);
+	unsigned int val;
+	int ret;
+
+	while (num_configs) {
+		val = pinconf_to_config_argument(*configs);
+
+		switch (pinconf_to_config_param(*configs)) {
+		case PIN_CONFIG_DRIVE_STRENGTH:
+			ret = cs42l43_pin_set_drv_str(priv, pin, val);
+			if (ret)
+				return ret;
+			break;
+		case PIN_CONFIG_INPUT_DEBOUNCE:
+			ret = cs42l43_pin_set_db(priv, pin, val);
+			if (ret)
+				return ret;
+			break;
+		default:
+			return -ENOTSUPP;
+		}
+
+		configs++;
+		num_configs--;
+	}
+
+	return 0;
+}
+
+static int cs42l43_pin_config_group_get(struct pinctrl_dev *pctldev,
+					unsigned int selector, unsigned long *config)
+{
+	int i, ret;
+
+	for (i = 0; i < cs42l43_pin_groups[selector].npins; ++i) {
+		ret = cs42l43_pin_config_get(pctldev,
+					     cs42l43_pin_groups[selector].pins[i],
+					     config);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int cs42l43_pin_config_group_set(struct pinctrl_dev *pctldev,
+					unsigned int selector,
+					unsigned long *configs,
+					unsigned int num_configs)
+{
+	int i, ret;
+
+	for (i = 0; i < cs42l43_pin_groups[selector].npins; ++i) {
+		ret = cs42l43_pin_config_set(pctldev,
+					     cs42l43_pin_groups[selector].pins[i],
+					     configs, num_configs);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static const struct pinconf_ops cs42l43_pin_conf_ops = {
+	.is_generic		= true,
+
+	.pin_config_get		= cs42l43_pin_config_get,
+	.pin_config_set		= cs42l43_pin_config_set,
+	.pin_config_group_get	= cs42l43_pin_config_group_get,
+	.pin_config_group_set	= cs42l43_pin_config_group_set,
+};
+
+static struct pinctrl_desc cs42l43_pin_desc = {
+	.name		= "cs42l43-pinctrl",
+	.owner		= THIS_MODULE,
+
+	.pins		= cs42l43_pin_pins,
+	.npins		= ARRAY_SIZE(cs42l43_pin_pins),
+
+	.pctlops	= &cs42l43_pin_group_ops,
+	.pmxops		= &cs42l43_pin_mux_ops,
+	.confops	= &cs42l43_pin_conf_ops,
+};
+
+static int cs42l43_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+	struct cs42l43_pin *priv = gpiochip_get_data(chip);
+	unsigned int val;
+	int ret;
+
+	ret = pm_runtime_resume_and_get(priv->dev);
+	if (ret) {
+		dev_err(priv->dev, "Failed to resume for get: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_read(priv->regmap, CS42L43_GPIO_STS, &val);
+	if (ret)
+		dev_err(priv->dev, "Failed to get gpio%d: %d\n", offset + 1, ret);
+	else
+		ret = !!(val & BIT(offset + CS42L43_GPIO1_STS_SHIFT));
+
+	pm_runtime_put(priv->dev);
+
+	return ret;
+}
+
+static void cs42l43_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
+{
+	struct cs42l43_pin *priv = gpiochip_get_data(chip);
+	unsigned int shift = offset + CS42L43_GPIO1_LVL_SHIFT;
+	int ret;
+
+	dev_dbg(priv->dev, "Setting gpio%d to %s\n",
+		offset + 1, value ? "high" : "low");
+
+	ret = pm_runtime_resume_and_get(priv->dev);
+	if (ret) {
+		dev_err(priv->dev, "Failed to resume for set: %d\n", ret);
+		return;
+	}
+
+	ret = regmap_update_bits(priv->regmap, CS42L43_GPIO_CTRL1,
+				 BIT(shift), value << shift);
+	if (ret)
+		dev_err(priv->dev, "Failed to set gpio%d: %d\n", offset + 1, ret);
+
+	pm_runtime_put(priv->dev);
+}
+
+static int cs42l43_gpio_direction_in(struct gpio_chip *chip, unsigned int offset)
+{
+	return pinctrl_gpio_direction_input(chip->base + offset);
+}
+
+static int cs42l43_gpio_direction_out(struct gpio_chip *chip,
+				      unsigned int offset, int value)
+{
+	cs42l43_gpio_set(chip, offset, value);
+
+	return pinctrl_gpio_direction_output(chip->base + offset);
+}
+
+static int cs42l43_gpio_add_pin_ranges(struct gpio_chip *chip)
+{
+	struct cs42l43_pin *priv = gpiochip_get_data(chip);
+	int ret;
+
+	ret = gpiochip_add_pin_range(&priv->gpio_chip, priv->gpio_chip.label,
+				     0, 0, CS42L43_NUM_GPIOS);
+	if (ret)
+		dev_err(priv->dev, "Failed to add GPIO pin range: %d\n", ret);
+
+	return ret;
+}
+
+static int cs42l43_pin_probe(struct platform_device *pdev)
+{
+	struct cs42l43 *cs42l43 = dev_get_drvdata(pdev->dev.parent);
+	struct cs42l43_pin *priv;
+	struct pinctrl_dev *pctldev;
+	struct fwnode_handle *fwnode = dev_fwnode(cs42l43->dev);
+	int ret;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->dev = &pdev->dev;
+	priv->regmap = cs42l43->regmap;
+
+	priv->shutters_locked = cs42l43->hw_lock;
+
+	priv->gpio_chip.request = gpiochip_generic_request;
+	priv->gpio_chip.free = gpiochip_generic_free;
+	priv->gpio_chip.direction_input = cs42l43_gpio_direction_in;
+	priv->gpio_chip.direction_output = cs42l43_gpio_direction_out;
+	priv->gpio_chip.add_pin_ranges = cs42l43_gpio_add_pin_ranges;
+	priv->gpio_chip.get = cs42l43_gpio_get;
+	priv->gpio_chip.set = cs42l43_gpio_set;
+	priv->gpio_chip.label = dev_name(priv->dev);
+	priv->gpio_chip.parent = priv->dev;
+	priv->gpio_chip.can_sleep = true;
+	priv->gpio_chip.base = -1;
+	priv->gpio_chip.ngpio = CS42L43_NUM_GPIOS;
+
+	if (is_of_node(fwnode)) {
+		fwnode = fwnode_get_named_child_node(fwnode, "pinctrl");
+
+		if (fwnode && !fwnode->dev)
+			fwnode->dev = priv->dev;
+	}
+
+	priv->gpio_chip.fwnode = fwnode;
+
+	device_set_node(priv->dev, fwnode);
+
+	devm_pm_runtime_enable(priv->dev);
+	pm_runtime_idle(priv->dev);
+
+	pctldev = devm_pinctrl_register(priv->dev, &cs42l43_pin_desc, priv);
+	if (IS_ERR(pctldev))
+		return dev_err_probe(priv->dev, PTR_ERR(pctldev),
+				     "Failed to register pinctrl\n");
+
+	ret = devm_gpiochip_add_data(priv->dev, &priv->gpio_chip, priv);
+	if (ret)
+		return dev_err_probe(priv->dev, ret,
+				     "Failed to register gpiochip\n");
+
+	return 0;
+}
+
+static const struct platform_device_id cs42l43_pin_id_table[] = {
+	{ "cs42l43-pinctrl", },
+	{}
+};
+MODULE_DEVICE_TABLE(platform, cs42l43_pin_id_table);
+
+static struct platform_driver cs42l43_pin_driver = {
+	.driver = {
+		.name	= "cs42l43-pinctrl",
+	},
+	.probe		= cs42l43_pin_probe,
+	.id_table	= cs42l43_pin_id_table,
+};
+module_platform_driver(cs42l43_pin_driver);
+
+MODULE_DESCRIPTION("CS42L43 Pinctrl Driver");
+MODULE_AUTHOR("Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>");
+MODULE_LICENSE("GPL");
-- 
2.30.2