--- /dev/null
+// 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/regmap.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/slab.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/version.h>
+#include <linux/gpio/consumer.h>
+#include <linux/gpio/driver.h>
+#include <linux/pinctrl/pinconf.h>
+#include <linux/pinctrl/pinctrl.h>
+#include <linux/pinctrl/pinmux.h>
+#include <linux/pinctrl/pinconf-generic.h>
+#include <linux/regulator/consumer.h>
+
+#include "core.h"
+#include "pinconf.h"
+#include "pinctrl-utils.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 -ENOTSUPP;
+ }
+ *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, ®);
+ 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 -ENOTSUPP;
+ }
+ 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, ®);
+ 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 = -ENOTSUPP;
+ 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 = -ENOTSUPP;
+ 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,
+};
+
+#if LINUX_VERSION_CODE <= KERNEL_VERSION(5, 5, 0)
+#define GPIO_LINE_DIRECTION_IN 1
+#define GPIO_LINE_DIRECTION_OUT 0
+#endif
+
+/*
+ * 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 val, ret;
+
+ ret = regmap_read(regmap, AW9523_REG_CONF_STATE(pin), &val);
+ if (ret < 0)
+ return ret;
+
+ return (val & BIT(n)) == BIT(n);
+}
+
+/*
+ * 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);
+}
+
+#if LINUX_VERSION_CODE <= KERNEL_VERSION(5, 5, 0)
+#undef GPIO_LINE_DIRECTION_IN
+#undef GPIO_LINE_DIRECTION_OUT
+#endif
+
+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));
+}
+
+/*
+ * 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;
+
+ 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 *gpiochip = &awi->gpio;
+
+ gpiochip->label = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
+ if (!gpiochip->label)
+ return -ENOMEM;
+
+ gpiochip->base = -1;
+ gpiochip->ngpio = npins;
+ gpiochip->get_direction = aw9523_gpio_get_direction;
+ gpiochip->direction_input = aw9523_direction_input;
+ gpiochip->direction_output = aw9523_direction_output;
+ gpiochip->get = aw9523_gpio_get;
+ gpiochip->get_multiple = aw9523_gpio_get_multiple;
+ gpiochip->set = aw9523_gpio_set;
+ gpiochip->set_multiple = aw9523_gpio_set_multiple;
+ gpiochip->set_config = gpiochip_generic_config;
+ gpiochip->parent = dev;
+ gpiochip->of_node = dev->of_node;
+ gpiochip->owner = THIS_MODULE;
+ gpiochip->can_sleep = false;
+
+ return 0;
+}
+
+static int aw9523_init_irq(struct aw9523 *awi, int irq)
+{
+ struct device *dev = awi->dev;
+ struct gpio_irq_chip *gpioirq;
+ 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;
+
+ irqchip->name = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
+ if (!irqchip->name)
+ return -ENOMEM;
+
+ irqchip->irq_mask = aw9523_irq_mask;
+ irqchip->irq_unmask = aw9523_irq_unmask;
+ irqchip->irq_bus_lock = aw9523_irq_bus_lock;
+ irqchip->irq_bus_sync_unlock = aw9523_irq_bus_sync_unlock;
+ irqchip->irq_set_type = aw9523_gpio_irq_type;
+ 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;
+ }
+
+ gpioirq = &awi->gpio.irq;
+ gpioirq->chip = irqchip;
+ gpioirq->parent_handler = NULL;
+ gpioirq->num_parents = 0;
+ gpioirq->parents = NULL;
+ gpioirq->default_type = IRQ_TYPE_LEVEL_MASK;
+ gpioirq->handler = handle_simple_irq;
+ gpioirq->threaded = true;
+ gpioirq->first = 0;
+
+ 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,
+ const struct i2c_device_id *id)
+{
+ 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 int aw9523_remove(struct i2c_client *client)
+{
+ struct aw9523 *awi = i2c_get_clientdata(client);
+ int ret;
+
+ if (!awi)
+ return 0;
+
+ /*
+ * 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 ret;
+ }
+
+ mutex_destroy(&awi->i2c_lock);
+ return 0;
+}
+
+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");
+MODULE_ALIAS("platform:aw9523");
projects / openwrt / staging / ynezz.git / commitdiff