Merging upstream version 6.9.7.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1119 insertions, 0 deletions

diff --git a/drivers/pinctrl/pinctrl-aw9523.c b/drivers/pinctrl/pinctrl-aw9523.c
new file mode 100644
index 0000000000..4edd371c46
--- /dev/null
+++ b/drivers/pinctrl/pinctrl-aw9523.c
@@ -0,0 +1,1119 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Awinic AW9523B i2c pin controller driver
+ * Copyright (c) 2020, AngeloGioacchino Del Regno
+ *                     <angelogioacchino.delregno@somainline.org>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/gpio/consumer.h>
+#include <linux/gpio/driver.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/mutex.h>
+#include <linux/module.h>
+#include <linux/pinctrl/pinconf.h>
+#include <linux/pinctrl/pinctrl.h>
+#include <linux/pinctrl/pinmux.h>
+#include <linux/pinctrl/pinconf-generic.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+#define AW9523_MAX_FUNCS		2
+#define AW9523_NUM_PORTS		2
+#define AW9523_PINS_PER_PORT		8
+
+/*
+ * HW needs at least 20uS for reset and at least 1-2uS to recover from
+ * reset, but we have to account for eventual board quirks, if any:
+ * for this reason, keep reset asserted for 50uS and wait for 20uS
+ * to recover from the reset.
+ */
+#define AW9523_HW_RESET_US		50
+#define AW9523_HW_RESET_RECOVERY_US	20
+
+/* Port 0: P0_0...P0_7 - Port 1: P1_0...P1_7 */
+#define AW9523_PIN_TO_PORT(pin)		(pin >> 3)
+#define AW9523_REG_IN_STATE(pin)	(0x00 + AW9523_PIN_TO_PORT(pin))
+#define AW9523_REG_OUT_STATE(pin)	(0x02 + AW9523_PIN_TO_PORT(pin))
+#define AW9523_REG_CONF_STATE(pin)	(0x04 + AW9523_PIN_TO_PORT(pin))
+#define AW9523_REG_INTR_DIS(pin)	(0x06 + AW9523_PIN_TO_PORT(pin))
+#define AW9523_REG_CHIPID		0x10
+#define AW9523_VAL_EXPECTED_CHIPID	0x23
+
+#define AW9523_REG_GCR			0x11
+#define AW9523_GCR_ISEL_MASK		GENMASK(0, 1)
+#define AW9523_GCR_GPOMD_MASK		BIT(4)
+
+#define AW9523_REG_PORT_MODE(pin)	(0x12 + AW9523_PIN_TO_PORT(pin))
+#define AW9523_REG_SOFT_RESET		0x7f
+#define AW9523_VAL_RESET		0x00
+
+/*
+ * struct aw9523_irq - Interrupt controller structure
+ * @lock: mutex locking for the irq bus
+ * @irqchip: structure holding irqchip params
+ * @cached_gpio: stores the previous gpio status for bit comparison
+ */
+struct aw9523_irq {
+	struct mutex lock;
+	struct irq_chip *irqchip;
+	u16 cached_gpio;
+};
+
+/*
+ * struct aw9523_pinmux - Pin mux params
+ * @name: Name of the mux
+ * @grps: Groups of the mux
+ * @num_grps: Number of groups (sizeof array grps)
+ */
+struct aw9523_pinmux {
+	const char *name;
+	const char * const *grps;
+	const u8 num_grps;
+};
+
+/*
+ * struct aw9523 - Main driver structure
+ * @dev: device handle
+ * @regmap: regmap handle for current device
+ * @i2c_lock: Mutex lock for i2c operations
+ * @reset_gpio: Hardware reset (RSTN) signal GPIO
+ * @vio_vreg: VCC regulator (Optional)
+ * @pctl: pinctrl handle for current device
+ * @gpio: structure holding gpiochip params
+ * @irq: Interrupt controller structure
+ */
+struct aw9523 {
+	struct device *dev;
+	struct regmap *regmap;
+	struct mutex i2c_lock;
+	struct gpio_desc *reset_gpio;
+	struct regulator *vio_vreg;
+	struct pinctrl_dev *pctl;
+	struct gpio_chip gpio;
+	struct aw9523_irq *irq;
+};
+
+static const struct pinctrl_pin_desc aw9523_pins[] = {
+	/* Port 0 */
+	PINCTRL_PIN(0, "gpio0"),
+	PINCTRL_PIN(1, "gpio1"),
+	PINCTRL_PIN(2, "gpio2"),
+	PINCTRL_PIN(3, "gpio3"),
+	PINCTRL_PIN(4, "gpio4"),
+	PINCTRL_PIN(5, "gpio5"),
+	PINCTRL_PIN(6, "gpio6"),
+	PINCTRL_PIN(7, "gpio7"),
+
+	/* Port 1 */
+	PINCTRL_PIN(8, "gpio8"),
+	PINCTRL_PIN(9, "gpio9"),
+	PINCTRL_PIN(10, "gpio10"),
+	PINCTRL_PIN(11, "gpio11"),
+	PINCTRL_PIN(12, "gpio12"),
+	PINCTRL_PIN(13, "gpio13"),
+	PINCTRL_PIN(14, "gpio14"),
+	PINCTRL_PIN(15, "gpio15"),
+};
+
+static int aw9523_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
+{
+	return ARRAY_SIZE(aw9523_pins);
+}
+
+static const char *aw9523_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
+						 unsigned int selector)
+{
+	return aw9523_pins[selector].name;
+}
+
+static int aw9523_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
+					 unsigned int selector,
+					 const unsigned int **pins,
+					 unsigned int *num_pins)
+{
+	*pins = &aw9523_pins[selector].number;
+	*num_pins = 1;
+	return 0;
+}
+
+static const struct pinctrl_ops aw9523_pinctrl_ops = {
+	.get_groups_count = aw9523_pinctrl_get_groups_count,
+	.get_group_pins = aw9523_pinctrl_get_group_pins,
+	.get_group_name = aw9523_pinctrl_get_group_name,
+	.dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
+	.dt_free_map = pinconf_generic_dt_free_map,
+};
+
+static const char * const gpio_pwm_groups[] = {
+	"gpio0", "gpio1", "gpio2", "gpio3", "gpio4", "gpio5",
+	"gpio6", "gpio7", "gpio8", "gpio9", "gpio10", "gpio11",
+	"gpio12", "gpio13", "gpio14", "gpio15"
+};
+
+/* Warning: Do NOT reorder this array */
+static const struct aw9523_pinmux aw9523_pmx[] = {
+	{
+		.name = "pwm",
+		.grps = gpio_pwm_groups,
+		.num_grps = ARRAY_SIZE(gpio_pwm_groups),
+	},
+	{
+		.name = "gpio",
+		.grps = gpio_pwm_groups,
+		.num_grps = ARRAY_SIZE(gpio_pwm_groups),
+	},
+};
+
+static int aw9523_pmx_get_funcs_count(struct pinctrl_dev *pctl)
+{
+	return ARRAY_SIZE(aw9523_pmx);
+}
+
+static const char *aw9523_pmx_get_fname(struct pinctrl_dev *pctl,
+					unsigned int sel)
+{
+	return aw9523_pmx[sel].name;
+}
+
+static int aw9523_pmx_get_groups(struct pinctrl_dev *pctl, unsigned int sel,
+				 const char * const **groups,
+				 unsigned int * const num_groups)
+{
+	*groups = aw9523_pmx[sel].grps;
+	*num_groups = aw9523_pmx[sel].num_grps;
+	return 0;
+}
+
+static int aw9523_pmx_set_mux(struct pinctrl_dev *pctl, unsigned int fsel,
+			      unsigned int grp)
+{
+	struct aw9523 *awi = pinctrl_dev_get_drvdata(pctl);
+	int ret, pin = aw9523_pins[grp].number % AW9523_PINS_PER_PORT;
+
+	if (fsel >= ARRAY_SIZE(aw9523_pmx))
+		return -EINVAL;
+
+	/*
+	 * This maps directly to the aw9523_pmx array: programming a
+	 * high bit means "gpio" and a low bit means "pwm".
+	 */
+	mutex_lock(&awi->i2c_lock);
+	ret = regmap_update_bits(awi->regmap, AW9523_REG_PORT_MODE(pin),
+				 BIT(pin), (fsel ? BIT(pin) : 0));
+	mutex_unlock(&awi->i2c_lock);
+	return ret;
+}
+
+static const struct pinmux_ops aw9523_pinmux_ops = {
+	.get_functions_count	= aw9523_pmx_get_funcs_count,
+	.get_function_name	= aw9523_pmx_get_fname,
+	.get_function_groups	= aw9523_pmx_get_groups,
+	.set_mux		= aw9523_pmx_set_mux,
+};
+
+static int aw9523_pcfg_param_to_reg(enum pin_config_param pcp, int pin, u8 *r)
+{
+	u8 reg;
+
+	switch (pcp) {
+	case PIN_CONFIG_BIAS_PULL_PIN_DEFAULT:
+	case PIN_CONFIG_BIAS_PULL_DOWN:
+	case PIN_CONFIG_BIAS_PULL_UP:
+		reg = AW9523_REG_IN_STATE(pin);
+		break;
+	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
+	case PIN_CONFIG_DRIVE_PUSH_PULL:
+		reg = AW9523_REG_GCR;
+		break;
+	case PIN_CONFIG_INPUT_ENABLE:
+	case PIN_CONFIG_OUTPUT_ENABLE:
+		reg = AW9523_REG_CONF_STATE(pin);
+		break;
+	case PIN_CONFIG_OUTPUT:
+		reg = AW9523_REG_OUT_STATE(pin);
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+	*r = reg;
+
+	return 0;
+}
+
+static int aw9523_pconf_get(struct pinctrl_dev *pctldev, unsigned int pin,
+			    unsigned long *config)
+{
+	struct aw9523 *awi = pinctrl_dev_get_drvdata(pctldev);
+	enum pin_config_param param = pinconf_to_config_param(*config);
+	int regbit = pin % AW9523_PINS_PER_PORT;
+	unsigned int val;
+	u8 reg;
+	int rc;
+
+	rc = aw9523_pcfg_param_to_reg(param, pin, &reg);
+	if (rc)
+		return rc;
+
+	mutex_lock(&awi->i2c_lock);
+	rc = regmap_read(awi->regmap, reg, &val);
+	mutex_unlock(&awi->i2c_lock);
+	if (rc)
+		return rc;
+
+	switch (param) {
+	case PIN_CONFIG_BIAS_PULL_UP:
+	case PIN_CONFIG_INPUT_ENABLE:
+	case PIN_CONFIG_OUTPUT:
+		val &= BIT(regbit);
+		break;
+	case PIN_CONFIG_BIAS_PULL_DOWN:
+	case PIN_CONFIG_OUTPUT_ENABLE:
+		val &= BIT(regbit);
+		val = !val;
+		break;
+	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
+		if (pin >= AW9523_PINS_PER_PORT)
+			val = 0;
+		else
+			val = !FIELD_GET(AW9523_GCR_GPOMD_MASK, val);
+		break;
+	case PIN_CONFIG_DRIVE_PUSH_PULL:
+		if (pin >= AW9523_PINS_PER_PORT)
+			val = 1;
+		else
+			val = FIELD_GET(AW9523_GCR_GPOMD_MASK, val);
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+	if (val < 1)
+		return -EINVAL;
+
+	*config = pinconf_to_config_packed(param, !!val);
+
+	return rc;
+}
+
+static int aw9523_pconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
+			    unsigned long *configs, unsigned int num_configs)
+{
+	struct aw9523 *awi = pinctrl_dev_get_drvdata(pctldev);
+	enum pin_config_param param;
+	int regbit = pin % AW9523_PINS_PER_PORT;
+	u32 arg;
+	u8 reg;
+	unsigned int mask, val;
+	int i, rc;
+
+	mutex_lock(&awi->i2c_lock);
+	for (i = 0; i < num_configs; i++) {
+		param = pinconf_to_config_param(configs[i]);
+		arg = pinconf_to_config_argument(configs[i]);
+
+		rc = aw9523_pcfg_param_to_reg(param, pin, &reg);
+		if (rc)
+			goto end;
+
+		switch (param) {
+		case PIN_CONFIG_OUTPUT:
+			/* First, enable pin output */
+			rc = regmap_update_bits(awi->regmap,
+						AW9523_REG_CONF_STATE(pin),
+						BIT(regbit), 0);
+			if (rc)
+				goto end;
+
+			/* Then, fall through to config output level */
+			fallthrough;
+		case PIN_CONFIG_OUTPUT_ENABLE:
+			arg = !arg;
+			fallthrough;
+		case PIN_CONFIG_BIAS_PULL_PIN_DEFAULT:
+		case PIN_CONFIG_BIAS_PULL_DOWN:
+		case PIN_CONFIG_BIAS_PULL_UP:
+		case PIN_CONFIG_INPUT_ENABLE:
+			mask = BIT(regbit);
+			val = arg ? BIT(regbit) : 0;
+			break;
+		case PIN_CONFIG_DRIVE_OPEN_DRAIN:
+			/* Open-Drain is supported only on port 0 */
+			if (pin >= AW9523_PINS_PER_PORT) {
+				rc = -EOPNOTSUPP;
+				goto end;
+			}
+			mask = AW9523_GCR_GPOMD_MASK;
+			val = 0;
+			break;
+		case PIN_CONFIG_DRIVE_PUSH_PULL:
+			/* Port 1 is always Push-Pull */
+			if (pin >= AW9523_PINS_PER_PORT) {
+				mask = 0;
+				val = 0;
+				continue;
+			}
+			mask = AW9523_GCR_GPOMD_MASK;
+			val = AW9523_GCR_GPOMD_MASK;
+			break;
+		default:
+			rc = -EOPNOTSUPP;
+			goto end;
+		}
+
+		rc = regmap_update_bits(awi->regmap, reg, mask, val);
+		if (rc)
+			goto end;
+	}
+end:
+	mutex_unlock(&awi->i2c_lock);
+	return rc;
+}
+
+static const struct pinconf_ops aw9523_pinconf_ops = {
+	.pin_config_get = aw9523_pconf_get,
+	.pin_config_set = aw9523_pconf_set,
+	.is_generic = true,
+};
+
+/*
+ * aw9523_get_pin_direction - Get pin direction
+ * @regmap: Regmap structure
+ * @pin: gpiolib pin number
+ * @n:   pin index in port register
+ *
+ * Return: Pin direction for success or negative number for error
+ */
+static int aw9523_get_pin_direction(struct regmap *regmap, u8 pin, u8 n)
+{
+	int ret;
+
+	ret = regmap_test_bits(regmap, AW9523_REG_CONF_STATE(pin), BIT(n));
+	if (ret < 0)
+		return ret;
+
+	return ret ? GPIO_LINE_DIRECTION_IN : GPIO_LINE_DIRECTION_OUT;
+}
+
+/*
+ * aw9523_get_port_state - Get input or output state for entire port
+ * @regmap: Regmap structure
+ * @pin:    gpiolib pin number
+ * @regbit: hw pin index, used to retrieve port number
+ * @state:  returned port state
+ *
+ * Return: Zero for success or negative number for error
+ */
+static int aw9523_get_port_state(struct regmap *regmap, u8 pin,
+				   u8 regbit, unsigned int *state)
+{
+	u8 reg;
+	int dir;
+
+	dir = aw9523_get_pin_direction(regmap, pin, regbit);
+	if (dir < 0)
+		return dir;
+
+	if (dir == GPIO_LINE_DIRECTION_IN)
+		reg = AW9523_REG_IN_STATE(pin);
+	else
+		reg = AW9523_REG_OUT_STATE(pin);
+
+	return regmap_read(regmap, reg, state);
+}
+
+static int aw9523_gpio_irq_type(struct irq_data *d, unsigned int type)
+{
+	switch (type) {
+	case IRQ_TYPE_NONE:
+	case IRQ_TYPE_EDGE_BOTH:
+		return 0;
+	default:
+		return -EINVAL;
+	};
+}
+
+/*
+ * aw9523_irq_mask - Mask interrupt
+ * @d: irq data
+ *
+ * Sets which interrupt to mask in the bitmap;
+ * The interrupt will be masked when unlocking the irq bus.
+ */
+static void aw9523_irq_mask(struct irq_data *d)
+{
+	struct aw9523 *awi = gpiochip_get_data(irq_data_get_irq_chip_data(d));
+	unsigned int n = d->hwirq % AW9523_PINS_PER_PORT;
+
+	regmap_update_bits(awi->regmap,
+			   AW9523_REG_INTR_DIS(d->hwirq),
+			   BIT(n), BIT(n));
+	gpiochip_disable_irq(&awi->gpio, irqd_to_hwirq(d));
+}
+
+/*
+ * aw9523_irq_unmask - Unmask interrupt
+ * @d: irq data
+ *
+ * Sets which interrupt to unmask in the bitmap;
+ * The interrupt will be masked when unlocking the irq bus.
+ */
+static void aw9523_irq_unmask(struct irq_data *d)
+{
+	struct aw9523 *awi = gpiochip_get_data(irq_data_get_irq_chip_data(d));
+	unsigned int n = d->hwirq % AW9523_PINS_PER_PORT;
+
+	gpiochip_enable_irq(&awi->gpio, irqd_to_hwirq(d));
+	regmap_update_bits(awi->regmap,
+			   AW9523_REG_INTR_DIS(d->hwirq),
+			   BIT(n), 0);
+}
+
+static irqreturn_t aw9523_irq_thread_func(int irq, void *dev_id)
+{
+	struct aw9523 *awi = (struct aw9523 *)dev_id;
+	unsigned long n, val = 0;
+	unsigned long changed_gpio;
+	unsigned int tmp, port_pin, i, ret;
+
+	for (i = 0; i < AW9523_NUM_PORTS; i++) {
+		port_pin = i * AW9523_PINS_PER_PORT;
+		ret = regmap_read(awi->regmap,
+				  AW9523_REG_IN_STATE(port_pin),
+				  &tmp);
+		if (ret)
+			return ret;
+		val |= (u8)tmp << (i * 8);
+	}
+
+	/* Handle GPIO input release interrupt as well */
+	changed_gpio = awi->irq->cached_gpio ^ val;
+	awi->irq->cached_gpio = val;
+
+	/*
+	 * To avoid up to four *slow* i2c reads from any driver hooked
+	 * up to our interrupts, just check for the irq_find_mapping
+	 * result: if the interrupt is not mapped, then we don't want
+	 * to care about it.
+	 */
+	for_each_set_bit(n, &changed_gpio, awi->gpio.ngpio) {
+		tmp = irq_find_mapping(awi->gpio.irq.domain, n);
+		if (tmp <= 0)
+			continue;
+		handle_nested_irq(tmp);
+	}
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * aw9523_irq_bus_lock - Grab lock for interrupt operation
+ * @d: irq data
+ */
+static void aw9523_irq_bus_lock(struct irq_data *d)
+{
+	struct aw9523 *awi = gpiochip_get_data(irq_data_get_irq_chip_data(d));
+
+	mutex_lock(&awi->irq->lock);
+	regcache_cache_only(awi->regmap, true);
+}
+
+/*
+ * aw9523_irq_bus_sync_unlock - Synchronize state and unlock
+ * @d: irq data
+ *
+ * Writes the interrupt mask bits (found in the bit map) to the
+ * hardware, then unlocks the bus.
+ */
+static void aw9523_irq_bus_sync_unlock(struct irq_data *d)
+{
+	struct aw9523 *awi = gpiochip_get_data(irq_data_get_irq_chip_data(d));
+
+	regcache_cache_only(awi->regmap, false);
+	regcache_sync(awi->regmap);
+	mutex_unlock(&awi->irq->lock);
+}
+
+static int aw9523_gpio_get_direction(struct gpio_chip *chip,
+				     unsigned int offset)
+{
+	struct aw9523 *awi = gpiochip_get_data(chip);
+	u8 regbit = offset % AW9523_PINS_PER_PORT;
+	int ret;
+
+	mutex_lock(&awi->i2c_lock);
+	ret = aw9523_get_pin_direction(awi->regmap, offset, regbit);
+	mutex_unlock(&awi->i2c_lock);
+
+	return ret;
+}
+
+static int aw9523_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+	struct aw9523 *awi = gpiochip_get_data(chip);
+	u8 regbit = offset % AW9523_PINS_PER_PORT;
+	unsigned int val;
+	int ret;
+
+	mutex_lock(&awi->i2c_lock);
+	ret = aw9523_get_port_state(awi->regmap, offset, regbit, &val);
+	mutex_unlock(&awi->i2c_lock);
+	if (ret)
+		return ret;
+
+	return !!(val & BIT(regbit));
+}
+
+/**
+ * _aw9523_gpio_get_multiple - Get I/O state for an entire port
+ * @regmap: Regmap structure
+ * @pin: gpiolib pin number
+ * @regbit: hw pin index, used to retrieve port number
+ * @state: returned port I/O state
+ *
+ * Return: Zero for success or negative number for error
+ */
+static int _aw9523_gpio_get_multiple(struct aw9523 *awi, u8 regbit,
+				     u8 *state, u8 mask)
+{
+	u32 dir_in, val;
+	u8 m;
+	int ret;
+
+	/* Registers are 8-bits wide */
+	ret = regmap_read(awi->regmap, AW9523_REG_CONF_STATE(regbit), &dir_in);
+	if (ret)
+		return ret;
+	*state = 0;
+
+	m = mask & dir_in;
+	if (m) {
+		ret = regmap_read(awi->regmap, AW9523_REG_IN_STATE(regbit),
+				  &val);
+		if (ret)
+			return ret;
+		*state |= (u8)val & m;
+	}
+
+	m = mask & ~dir_in;
+	if (m) {
+		ret = regmap_read(awi->regmap, AW9523_REG_OUT_STATE(regbit),
+				  &val);
+		if (ret)
+			return ret;
+		*state |= (u8)val & m;
+	}
+
+	return 0;
+}
+
+static int aw9523_gpio_get_multiple(struct gpio_chip *chip,
+				    unsigned long *mask,
+				    unsigned long *bits)
+{
+	struct aw9523 *awi = gpiochip_get_data(chip);
+	u8 m, state = 0;
+	int ret;
+
+	mutex_lock(&awi->i2c_lock);
+
+	/* Port 0 (gpio 0-7) */
+	m = *mask & U8_MAX;
+	if (m) {
+		ret = _aw9523_gpio_get_multiple(awi, 0, &state, m);
+		if (ret)
+			goto out;
+	}
+	*bits = state;
+
+	/* Port 1 (gpio 8-15) */
+	m = (*mask >> 8) & U8_MAX;
+	if (m) {
+		ret = _aw9523_gpio_get_multiple(awi, AW9523_PINS_PER_PORT,
+						&state, m);
+		if (ret)
+			goto out;
+
+		*bits |= (state << 8);
+	}
+out:
+	mutex_unlock(&awi->i2c_lock);
+	return ret;
+}
+
+static void aw9523_gpio_set_multiple(struct gpio_chip *chip,
+				    unsigned long *mask,
+				    unsigned long *bits)
+{
+	struct aw9523 *awi = gpiochip_get_data(chip);
+	u8 mask_lo, mask_hi, bits_lo, bits_hi;
+	unsigned int reg;
+	int ret = 0;
+
+	mask_lo = *mask & U8_MAX;
+	mask_hi = (*mask >> 8) & U8_MAX;
+	mutex_lock(&awi->i2c_lock);
+	if (mask_hi) {
+		reg = AW9523_REG_OUT_STATE(AW9523_PINS_PER_PORT);
+		bits_hi = (*bits >> 8) & U8_MAX;
+
+		ret = regmap_write_bits(awi->regmap, reg, mask_hi, bits_hi);
+		if (ret) {
+			dev_warn(awi->dev, "Cannot write port1 out level\n");
+			goto out;
+		}
+	}
+	if (mask_lo) {
+		reg = AW9523_REG_OUT_STATE(0);
+		bits_lo = *bits & U8_MAX;
+		ret = regmap_write_bits(awi->regmap, reg, mask_lo, bits_lo);
+		if (ret)
+			dev_warn(awi->dev, "Cannot write port0 out level\n");
+	}
+out:
+	mutex_unlock(&awi->i2c_lock);
+}
+
+static void aw9523_gpio_set(struct gpio_chip *chip,
+			    unsigned int offset, int value)
+{
+	struct aw9523 *awi = gpiochip_get_data(chip);
+	u8 regbit = offset % AW9523_PINS_PER_PORT;
+
+	mutex_lock(&awi->i2c_lock);
+	regmap_update_bits(awi->regmap, AW9523_REG_OUT_STATE(offset),
+			   BIT(regbit), value ? BIT(regbit) : 0);
+	mutex_unlock(&awi->i2c_lock);
+}
+
+
+static int aw9523_direction_input(struct gpio_chip *chip, unsigned int offset)
+{
+	struct aw9523 *awi = gpiochip_get_data(chip);
+	u8 regbit = offset % AW9523_PINS_PER_PORT;
+	int ret;
+
+	mutex_lock(&awi->i2c_lock);
+	ret = regmap_update_bits(awi->regmap, AW9523_REG_CONF_STATE(offset),
+				 BIT(regbit), BIT(regbit));
+	mutex_unlock(&awi->i2c_lock);
+
+	return ret;
+}
+
+static int aw9523_direction_output(struct gpio_chip *chip,
+				   unsigned int offset, int value)
+{
+	struct aw9523 *awi = gpiochip_get_data(chip);
+	u8 regbit = offset % AW9523_PINS_PER_PORT;
+	int ret;
+
+	mutex_lock(&awi->i2c_lock);
+	ret = regmap_update_bits(awi->regmap, AW9523_REG_OUT_STATE(offset),
+				 BIT(regbit), value ? BIT(regbit) : 0);
+	if (ret)
+		goto end;
+
+	ret = regmap_update_bits(awi->regmap, AW9523_REG_CONF_STATE(offset),
+				 BIT(regbit), 0);
+end:
+	mutex_unlock(&awi->i2c_lock);
+	return ret;
+}
+
+static int aw9523_drive_reset_gpio(struct aw9523 *awi)
+{
+	unsigned int chip_id;
+	int ret;
+
+	/*
+	 * If the chip is already configured for any reason, then we
+	 * will probably succeed in sending the soft reset signal to
+	 * the hardware through I2C: this operation takes less time
+	 * compared to a full HW reset and it gives the same results.
+	 */
+	ret = regmap_write(awi->regmap, AW9523_REG_SOFT_RESET, 0);
+	if (ret == 0)
+		goto done;
+
+	dev_dbg(awi->dev, "Cannot execute soft reset: trying hard reset\n");
+	ret = gpiod_direction_output(awi->reset_gpio, 0);
+	if (ret)
+		return ret;
+
+	/* The reset pulse has to be longer than 20uS due to deglitch */
+	usleep_range(AW9523_HW_RESET_US, AW9523_HW_RESET_US + 1);
+
+	ret = gpiod_direction_output(awi->reset_gpio, 1);
+	if (ret)
+		return ret;
+done:
+	/* The HW needs at least 1uS to reliably recover after reset */
+	usleep_range(AW9523_HW_RESET_RECOVERY_US,
+		     AW9523_HW_RESET_RECOVERY_US + 1);
+
+	/* Check the ChipID */
+	ret = regmap_read(awi->regmap, AW9523_REG_CHIPID, &chip_id);
+	if (ret) {
+		dev_err(awi->dev, "Cannot read Chip ID: %d\n", ret);
+		return ret;
+	}
+	if (chip_id != AW9523_VAL_EXPECTED_CHIPID) {
+		dev_err(awi->dev, "Bad ChipID; read 0x%x, expected 0x%x\n",
+			chip_id, AW9523_VAL_EXPECTED_CHIPID);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int aw9523_hw_reset(struct aw9523 *awi)
+{
+	int ret, max_retries = 2;
+
+	/* Sometimes the chip needs more than one reset cycle */
+	do {
+		ret = aw9523_drive_reset_gpio(awi);
+		if (ret == 0)
+			break;
+		max_retries--;
+	} while (max_retries);
+
+	return ret;
+}
+
+static int aw9523_init_gpiochip(struct aw9523 *awi, unsigned int npins)
+{
+	struct device *dev = awi->dev;
+	struct gpio_chip *gc = &awi->gpio;
+
+	gc->label = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
+	if (!gc->label)
+		return -ENOMEM;
+
+	gc->base = -1;
+	gc->ngpio = npins;
+	gc->get_direction = aw9523_gpio_get_direction;
+	gc->direction_input = aw9523_direction_input;
+	gc->direction_output = aw9523_direction_output;
+	gc->get = aw9523_gpio_get;
+	gc->get_multiple = aw9523_gpio_get_multiple;
+	gc->set = aw9523_gpio_set;
+	gc->set_multiple = aw9523_gpio_set_multiple;
+	gc->set_config = gpiochip_generic_config;
+	gc->parent = dev;
+	gc->owner = THIS_MODULE;
+	gc->can_sleep = false;
+
+	return 0;
+}
+
+static const struct irq_chip aw9523_irq_chip = {
+	.name = "aw9523",
+	.irq_mask = aw9523_irq_mask,
+	.irq_unmask = aw9523_irq_unmask,
+	.irq_bus_lock = aw9523_irq_bus_lock,
+	.irq_bus_sync_unlock = aw9523_irq_bus_sync_unlock,
+	.irq_set_type = aw9523_gpio_irq_type,
+	.flags = IRQCHIP_IMMUTABLE,
+        GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
+static int aw9523_init_irq(struct aw9523 *awi, int irq)
+{
+	struct device *dev = awi->dev;
+	struct gpio_irq_chip *girq;
+	struct irq_chip *irqchip;
+	int ret;
+
+	if (!device_property_read_bool(dev, "interrupt-controller"))
+		return 0;
+
+	irqchip = devm_kzalloc(dev, sizeof(*irqchip), GFP_KERNEL);
+	if (!irqchip)
+		return -ENOMEM;
+
+	awi->irq = devm_kzalloc(dev, sizeof(*awi->irq), GFP_KERNEL);
+	if (!awi->irq)
+		return -ENOMEM;
+
+	awi->irq->irqchip = irqchip;
+	mutex_init(&awi->irq->lock);
+
+	ret = devm_request_threaded_irq(dev, irq, NULL, aw9523_irq_thread_func,
+					IRQF_ONESHOT, dev_name(dev), awi);
+	if (ret) {
+		dev_err(dev, "Failed to request irq %d\n", irq);
+		return ret;
+	}
+
+	girq = &awi->gpio.irq;
+	gpio_irq_chip_set_chip(girq, &aw9523_irq_chip);
+	girq->parent_handler = NULL;
+	girq->num_parents = 0;
+	girq->parents = NULL;
+	girq->default_type = IRQ_TYPE_EDGE_BOTH;
+	girq->handler = handle_simple_irq;
+	girq->threaded = true;
+
+	return 0;
+}
+
+static bool aw9523_is_reg_hole(unsigned int reg)
+{
+	return (reg > AW9523_REG_PORT_MODE(AW9523_PINS_PER_PORT) &&
+		reg < AW9523_REG_SOFT_RESET) ||
+	       (reg > AW9523_REG_INTR_DIS(AW9523_PINS_PER_PORT) &&
+		reg < AW9523_REG_CHIPID);
+}
+
+static bool aw9523_readable_reg(struct device *dev, unsigned int reg)
+{
+	/* All available registers (minus holes) can be read */
+	return !aw9523_is_reg_hole(reg);
+}
+
+static bool aw9523_volatile_reg(struct device *dev, unsigned int reg)
+{
+	return aw9523_is_reg_hole(reg) ||
+	       reg == AW9523_REG_IN_STATE(0) ||
+	       reg == AW9523_REG_IN_STATE(AW9523_PINS_PER_PORT) ||
+	       reg == AW9523_REG_CHIPID ||
+	       reg == AW9523_REG_SOFT_RESET;
+}
+
+static bool aw9523_writeable_reg(struct device *dev, unsigned int reg)
+{
+	return !aw9523_is_reg_hole(reg) && reg != AW9523_REG_CHIPID;
+}
+
+static bool aw9523_precious_reg(struct device *dev, unsigned int reg)
+{
+	/* Reading AW9523_REG_IN_STATE clears interrupt status */
+	return aw9523_is_reg_hole(reg) ||
+	       reg == AW9523_REG_IN_STATE(0) ||
+	       reg == AW9523_REG_IN_STATE(AW9523_PINS_PER_PORT);
+}
+
+static const struct regmap_config aw9523_regmap = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.reg_stride = 1,
+
+	.precious_reg = aw9523_precious_reg,
+	.readable_reg = aw9523_readable_reg,
+	.volatile_reg = aw9523_volatile_reg,
+	.writeable_reg = aw9523_writeable_reg,
+
+	.cache_type = REGCACHE_FLAT,
+	.disable_locking = true,
+
+	.num_reg_defaults_raw = AW9523_REG_SOFT_RESET,
+};
+
+static int aw9523_hw_init(struct aw9523 *awi)
+{
+	u8 p1_pin = AW9523_PINS_PER_PORT;
+	unsigned int val;
+	int ret;
+
+	/* No register caching during initialization */
+	regcache_cache_bypass(awi->regmap, true);
+
+	/* Bring up the chip */
+	ret = aw9523_hw_reset(awi);
+	if (ret) {
+		dev_err(awi->dev, "HW Reset failed: %d\n", ret);
+		return ret;
+	}
+
+	/*
+	 * This is the expected chip and it is running: it's time to
+	 * set a safe default configuration in case the user doesn't
+	 * configure (all of the available) pins in this chip.
+	 * P.S.: The writes order doesn't matter.
+	 */
+
+	/* Set all pins as GPIO */
+	ret = regmap_write(awi->regmap, AW9523_REG_PORT_MODE(0), U8_MAX);
+	if (ret)
+		return ret;
+	ret = regmap_write(awi->regmap, AW9523_REG_PORT_MODE(p1_pin), U8_MAX);
+	if (ret)
+		return ret;
+
+	/* Set Open-Drain mode on Port 0 (Port 1 is always P-P) */
+	ret = regmap_write(awi->regmap, AW9523_REG_GCR, 0);
+	if (ret)
+		return ret;
+
+	/* Set all pins as inputs */
+	ret = regmap_write(awi->regmap, AW9523_REG_CONF_STATE(0), U8_MAX);
+	if (ret)
+		return ret;
+	ret = regmap_write(awi->regmap, AW9523_REG_CONF_STATE(p1_pin), U8_MAX);
+	if (ret)
+		return ret;
+
+	/* Disable all interrupts to avoid unreasoned wakeups */
+	ret = regmap_write(awi->regmap, AW9523_REG_INTR_DIS(0), U8_MAX);
+	if (ret)
+		return ret;
+	ret = regmap_write(awi->regmap, AW9523_REG_INTR_DIS(p1_pin), U8_MAX);
+	if (ret)
+		return ret;
+
+	/* Clear setup-generated interrupts by performing a port state read */
+	ret = aw9523_get_port_state(awi->regmap, 0, 0, &val);
+	if (ret)
+		return ret;
+	ret = aw9523_get_port_state(awi->regmap, p1_pin, 0, &val);
+	if (ret)
+		return ret;
+
+	/* Everything went fine: activate and reinitialize register cache */
+	regcache_cache_bypass(awi->regmap, false);
+	return regmap_reinit_cache(awi->regmap, &aw9523_regmap);
+}
+
+static int aw9523_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct pinctrl_desc *pdesc;
+	struct aw9523 *awi;
+	int ret;
+
+	awi = devm_kzalloc(dev, sizeof(*awi), GFP_KERNEL);
+	if (!awi)
+		return -ENOMEM;
+
+	i2c_set_clientdata(client, awi);
+
+	awi->dev = dev;
+	awi->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(awi->reset_gpio))
+		return PTR_ERR(awi->reset_gpio);
+	gpiod_set_consumer_name(awi->reset_gpio, "aw9523 reset");
+
+	awi->regmap = devm_regmap_init_i2c(client, &aw9523_regmap);
+	if (IS_ERR(awi->regmap))
+		return PTR_ERR(awi->regmap);
+
+	awi->vio_vreg = devm_regulator_get_optional(dev, "vio");
+	if (IS_ERR(awi->vio_vreg)) {
+		if (PTR_ERR(awi->vio_vreg) == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+		awi->vio_vreg = NULL;
+	} else {
+		ret = regulator_enable(awi->vio_vreg);
+		if (ret)
+			return ret;
+	}
+
+	mutex_init(&awi->i2c_lock);
+	lockdep_set_subclass(&awi->i2c_lock,
+			     i2c_adapter_depth(client->adapter));
+
+	pdesc = devm_kzalloc(dev, sizeof(*pdesc), GFP_KERNEL);
+	if (!pdesc)
+		return -ENOMEM;
+
+	ret = aw9523_hw_init(awi);
+	if (ret)
+		goto err_disable_vregs;
+
+	pdesc->name = dev_name(dev);
+	pdesc->owner = THIS_MODULE;
+	pdesc->pctlops = &aw9523_pinctrl_ops;
+	pdesc->pmxops  = &aw9523_pinmux_ops;
+	pdesc->confops = &aw9523_pinconf_ops;
+	pdesc->pins = aw9523_pins;
+	pdesc->npins = ARRAY_SIZE(aw9523_pins);
+
+	ret = aw9523_init_gpiochip(awi, pdesc->npins);
+	if (ret)
+		goto err_disable_vregs;
+
+	if (client->irq) {
+		ret = aw9523_init_irq(awi, client->irq);
+		if (ret)
+			goto err_disable_vregs;
+	}
+
+	awi->pctl = devm_pinctrl_register(dev, pdesc, awi);
+	if (IS_ERR(awi->pctl)) {
+		ret = PTR_ERR(awi->pctl);
+		dev_err(dev, "Cannot register pinctrl: %d", ret);
+		goto err_disable_vregs;
+	}
+
+	ret = devm_gpiochip_add_data(dev, &awi->gpio, awi);
+	if (ret)
+		goto err_disable_vregs;
+
+	return ret;
+
+err_disable_vregs:
+	if (awi->vio_vreg)
+		regulator_disable(awi->vio_vreg);
+	mutex_destroy(&awi->i2c_lock);
+	return ret;
+}
+
+static void aw9523_remove(struct i2c_client *client)
+{
+	struct aw9523 *awi = i2c_get_clientdata(client);
+	int ret;
+
+	if (!awi)
+		return;
+
+	/*
+	 * If the chip VIO is connected to a regulator that we can turn
+	 * off, life is easy... otherwise, reinitialize the chip and
+	 * set the pins to hardware defaults before removing the driver
+	 * to leave it in a clean, safe and predictable state.
+	 */
+	if (awi->vio_vreg) {
+		regulator_disable(awi->vio_vreg);
+	} else {
+		mutex_lock(&awi->i2c_lock);
+		ret = aw9523_hw_init(awi);
+		mutex_unlock(&awi->i2c_lock);
+		if (ret)
+			return;
+	}
+
+	mutex_destroy(&awi->i2c_lock);
+}
+
+static const struct i2c_device_id aw9523_i2c_id_table[] = {
+	{ "aw9523_i2c", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, aw9523_i2c_id_table);
+
+static const struct of_device_id of_aw9523_i2c_match[] = {
+	{ .compatible = "awinic,aw9523-pinctrl", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, of_aw9523_i2c_match);
+
+static struct i2c_driver aw9523_driver = {
+	.driver = {
+		.name = "aw9523-pinctrl",
+		.of_match_table = of_aw9523_i2c_match,
+	},
+	.probe = aw9523_probe,
+	.remove = aw9523_remove,
+	.id_table = aw9523_i2c_id_table,
+};
+module_i2c_driver(aw9523_driver);
+
+MODULE_DESCRIPTION("Awinic AW9523 I2C GPIO Expander driver");
+MODULE_AUTHOR("AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>");
+MODULE_LICENSE("GPL v2");