--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018, STMicroelectronics - All Rights Reserved
+ *
+ * Driver for STMicroelectronics Multi-Function eXpander (STMFX) GPIO expander
+ * based on Linux driver : pinctrl/pinctrl-stmfx.c
+ */
+#include <common.h>
+#include <dm.h>
+#include <i2c.h>
+#include <asm/gpio.h>
+#include <dm/device.h>
+#include <dm/device-internal.h>
+#include <dm/lists.h>
+#include <dm/pinctrl.h>
+#include <linux/bitfield.h>
+#include <power/regulator.h>
+
+/* STMFX pins = GPIO[15:0] + aGPIO[7:0] */
+#define STMFX_MAX_GPIO 16
+#define STMFX_MAX_AGPIO 8
+
+/* General */
+#define STMFX_REG_CHIP_ID 0x00 /* R */
+#define STMFX_REG_FW_VERSION_MSB 0x01 /* R */
+#define STMFX_REG_FW_VERSION_LSB 0x02 /* R */
+#define STMFX_REG_SYS_CTRL 0x40 /* RW */
+
+/* MFX boot time is around 10ms, so after reset, we have to wait this delay */
+#define STMFX_BOOT_TIME_MS 10
+
+/* GPIOs expander */
+/* GPIO_STATE1 0x10, GPIO_STATE2 0x11, GPIO_STATE3 0x12 */
+#define STMFX_REG_GPIO_STATE 0x10 /* R */
+/* GPIO_DIR1 0x60, GPIO_DIR2 0x61, GPIO_DIR3 0x63 */
+#define STMFX_REG_GPIO_DIR 0x60 /* RW */
+/* GPIO_TYPE1 0x64, GPIO_TYPE2 0x65, GPIO_TYPE3 0x66 */
+#define STMFX_REG_GPIO_TYPE 0x64 /* RW */
+/* GPIO_PUPD1 0x68, GPIO_PUPD2 0x69, GPIO_PUPD3 0x6A */
+#define STMFX_REG_GPIO_PUPD 0x68 /* RW */
+/* GPO_SET1 0x6C, GPO_SET2 0x6D, GPO_SET3 0x6E */
+#define STMFX_REG_GPO_SET 0x6C /* RW */
+/* GPO_CLR1 0x70, GPO_CLR2 0x71, GPO_CLR3 0x72 */
+#define STMFX_REG_GPO_CLR 0x70 /* RW */
+
+/* STMFX_REG_CHIP_ID bitfields */
+#define STMFX_REG_CHIP_ID_MASK GENMASK(7, 0)
+
+/* STMFX_REG_SYS_CTRL bitfields */
+#define STMFX_REG_SYS_CTRL_GPIO_EN BIT(0)
+#define STMFX_REG_SYS_CTRL_ALTGPIO_EN BIT(3)
+#define STMFX_REG_SYS_CTRL_SWRST BIT(7)
+
+#define NR_GPIO_REGS 3
+#define NR_GPIOS_PER_REG 8
+#define get_reg(offset) ((offset) / NR_GPIOS_PER_REG)
+#define get_shift(offset) ((offset) % NR_GPIOS_PER_REG)
+#define get_mask(offset) (BIT(get_shift(offset)))
+
+struct stmfx_pinctrl {
+ struct udevice *gpio;
+};
+
+static int stmfx_read(struct udevice *dev, uint offset)
+{
+ return dm_i2c_reg_read(dev_get_parent(dev), offset);
+}
+
+static int stmfx_write(struct udevice *dev, uint offset, unsigned int val)
+{
+ return dm_i2c_reg_write(dev_get_parent(dev), offset, val);
+}
+
+static int stmfx_gpio_get(struct udevice *dev, unsigned int offset)
+{
+ u32 reg = STMFX_REG_GPIO_STATE + get_reg(offset);
+ u32 mask = get_mask(offset);
+ int ret;
+
+ ret = stmfx_read(dev, reg);
+
+ return ret < 0 ? ret : !!(ret & mask);
+}
+
+static int stmfx_gpio_set(struct udevice *dev, unsigned int offset, int value)
+{
+ u32 reg = value ? STMFX_REG_GPO_SET : STMFX_REG_GPO_CLR;
+ u32 mask = get_mask(offset);
+
+ return stmfx_write(dev, reg + get_reg(offset), mask);
+}
+
+static int stmfx_gpio_get_function(struct udevice *dev, unsigned int offset)
+{
+ u32 reg = STMFX_REG_GPIO_DIR + get_reg(offset);
+ u32 mask = get_mask(offset);
+ int ret;
+
+ ret = stmfx_read(dev, reg);
+
+ if (ret < 0)
+ return ret;
+ /* On stmfx, gpio pins direction is (0)input, (1)output. */
+
+ return ret & mask ? GPIOF_OUTPUT : GPIOF_INPUT;
+}
+
+static int stmfx_gpio_direction_input(struct udevice *dev, unsigned int offset)
+{
+ u32 reg = STMFX_REG_GPIO_DIR + get_reg(offset);
+ u32 mask = get_mask(offset);
+ int ret;
+
+ ret = stmfx_read(dev, reg);
+ if (ret < 0)
+ return ret;
+
+ ret &= ~mask;
+
+ return stmfx_write(dev, reg, ret & ~mask);
+}
+
+static int stmfx_gpio_direction_output(struct udevice *dev,
+ unsigned int offset, int value)
+{
+ u32 reg = STMFX_REG_GPIO_DIR + get_reg(offset);
+ u32 mask = get_mask(offset);
+ int ret;
+
+ ret = stmfx_gpio_set(dev, offset, value);
+ if (ret < 0)
+ return ret;
+
+ ret = stmfx_read(dev, reg);
+ if (ret < 0)
+ return ret;
+
+ return stmfx_write(dev, reg, ret | mask);
+}
+
+static int stmfx_gpio_probe(struct udevice *dev)
+{
+ struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+ struct ofnode_phandle_args args;
+ u8 sys_ctrl;
+
+ uc_priv->bank_name = "stmfx";
+ uc_priv->gpio_count = STMFX_MAX_GPIO + STMFX_MAX_AGPIO;
+ if (!dev_read_phandle_with_args(dev, "gpio-ranges",
+ NULL, 3, 0, &args)) {
+ uc_priv->gpio_count = args.args[2];
+ }
+
+ /* enable GPIO function */
+ sys_ctrl = STMFX_REG_SYS_CTRL_GPIO_EN;
+ if (uc_priv->gpio_count > STMFX_MAX_GPIO)
+ sys_ctrl |= STMFX_REG_SYS_CTRL_ALTGPIO_EN;
+ stmfx_write(dev, STMFX_REG_SYS_CTRL, sys_ctrl);
+
+ return 0;
+}
+
+static const struct dm_gpio_ops stmfx_gpio_ops = {
+ .set_value = stmfx_gpio_set,
+ .get_value = stmfx_gpio_get,
+ .get_function = stmfx_gpio_get_function,
+ .direction_input = stmfx_gpio_direction_input,
+ .direction_output = stmfx_gpio_direction_output,
+};
+
+U_BOOT_DRIVER(stmfx_gpio) = {
+ .name = "stmfx-gpio",
+ .id = UCLASS_GPIO,
+ .probe = stmfx_gpio_probe,
+ .ops = &stmfx_gpio_ops,
+};
+
+#if CONFIG_IS_ENABLED(PINCONF)
+static const struct pinconf_param stmfx_pinctrl_conf_params[] = {
+ { "bias-disable", PIN_CONFIG_BIAS_DISABLE, 0 },
+ { "bias-pull-up", PIN_CONFIG_BIAS_PULL_UP, 0 },
+ { "bias-pull-pin-default", PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 0 },
+ { "bias-pull-down", PIN_CONFIG_BIAS_PULL_DOWN, 0 },
+ { "drive-open-drain", PIN_CONFIG_DRIVE_OPEN_DRAIN, 0 },
+ { "drive-push-pull", PIN_CONFIG_DRIVE_PUSH_PULL, 0 },
+ { "output-high", PIN_CONFIG_OUTPUT, 1 },
+ { "output-low", PIN_CONFIG_OUTPUT, 0 },
+};
+
+static int stmfx_pinctrl_set_pupd(struct udevice *dev,
+ unsigned int pin, u32 pupd)
+{
+ u8 reg = STMFX_REG_GPIO_PUPD + get_reg(pin);
+ u32 mask = get_mask(pin);
+ int ret;
+
+ ret = stmfx_read(dev, reg);
+ if (ret < 0)
+ return ret;
+ ret = (ret & ~mask) | (pupd ? mask : 0);
+
+ return stmfx_write(dev, reg, ret);
+}
+
+static int stmfx_pinctrl_set_type(struct udevice *dev,
+ unsigned int pin, u32 type)
+{
+ u8 reg = STMFX_REG_GPIO_TYPE + get_reg(pin);
+ u32 mask = get_mask(pin);
+ int ret;
+
+ ret = stmfx_read(dev, reg);
+ if (ret < 0)
+ return ret;
+ ret = (ret & ~mask) | (type ? mask : 0);
+
+ return stmfx_write(dev, reg, ret);
+}
+
+static int stmfx_pinctrl_conf_set(struct udevice *dev, unsigned int pin,
+ unsigned int param, unsigned int arg)
+{
+ int ret, dir;
+ struct stmfx_pinctrl *plat = dev_get_platdata(dev);
+
+ dir = stmfx_gpio_get_function(plat->gpio, pin);
+
+ if (dir < 0)
+ return dir;
+
+ switch (param) {
+ case PIN_CONFIG_BIAS_PULL_PIN_DEFAULT:
+ case PIN_CONFIG_BIAS_DISABLE:
+ case PIN_CONFIG_BIAS_PULL_DOWN:
+ ret = stmfx_pinctrl_set_pupd(dev, pin, 0);
+ break;
+ case PIN_CONFIG_BIAS_PULL_UP:
+ ret = stmfx_pinctrl_set_pupd(dev, pin, 1);
+ break;
+ case PIN_CONFIG_DRIVE_OPEN_DRAIN:
+ if (dir == GPIOF_OUTPUT)
+ ret = stmfx_pinctrl_set_type(dev, pin, 1);
+ else
+ ret = stmfx_pinctrl_set_type(dev, pin, 0);
+ break;
+ case PIN_CONFIG_DRIVE_PUSH_PULL:
+ if (dir == GPIOF_OUTPUT)
+ ret = stmfx_pinctrl_set_type(dev, pin, 0);
+ else
+ ret = stmfx_pinctrl_set_type(dev, pin, 1);
+ break;
+ case PIN_CONFIG_OUTPUT:
+ ret = stmfx_gpio_direction_output(plat->gpio, pin, arg);
+ break;
+ default:
+ return -ENOTSUPP;
+ }
+
+ return ret;
+}
+#endif
+
+static int stmfx_pinctrl_get_pins_count(struct udevice *dev)
+{
+ struct stmfx_pinctrl *plat = dev_get_platdata(dev);
+ struct gpio_dev_priv *uc_priv;
+
+ uc_priv = dev_get_uclass_priv(plat->gpio);
+
+ return uc_priv->gpio_count;
+}
+
+/*
+ * STMFX pins[15:0] are called "gpio[15:0]"
+ * and STMFX pins[23:16] are called "agpio[7:0]"
+ */
+#define MAX_PIN_NAME_LEN 7
+static char pin_name[MAX_PIN_NAME_LEN];
+static const char *stmfx_pinctrl_get_pin_name(struct udevice *dev,
+ unsigned int selector)
+{
+ if (selector < STMFX_MAX_GPIO)
+ snprintf(pin_name, MAX_PIN_NAME_LEN, "gpio%u", selector);
+ else
+ snprintf(pin_name, MAX_PIN_NAME_LEN, "agpio%u", selector - 16);
+ return pin_name;
+}
+
+static int stmfx_pinctrl_get_pin_muxing(struct udevice *dev,
+ unsigned int selector,
+ char *buf, int size)
+{
+ struct stmfx_pinctrl *plat = dev_get_platdata(dev);
+ int func;
+
+ func = stmfx_gpio_get_function(plat->gpio, selector);
+ if (func < 0)
+ return func;
+
+ snprintf(buf, size, "%s", func == GPIOF_INPUT ? "input" : "output");
+
+ return 0;
+}
+
+static int stmfx_pinctrl_bind(struct udevice *dev)
+{
+ struct stmfx_pinctrl *plat = dev_get_platdata(dev);
+
+ return device_bind_driver_to_node(dev->parent,
+ "stmfx-gpio", "stmfx-gpio",
+ dev_ofnode(dev), &plat->gpio);
+};
+
+static int stmfx_pinctrl_probe(struct udevice *dev)
+{
+ struct stmfx_pinctrl *plat = dev_get_platdata(dev);
+
+ return device_probe(plat->gpio);
+};
+
+const struct pinctrl_ops stmfx_pinctrl_ops = {
+ .get_pins_count = stmfx_pinctrl_get_pins_count,
+ .get_pin_name = stmfx_pinctrl_get_pin_name,
+ .set_state = pinctrl_generic_set_state,
+ .get_pin_muxing = stmfx_pinctrl_get_pin_muxing,
+#if CONFIG_IS_ENABLED(PINCONF)
+ .pinconf_set = stmfx_pinctrl_conf_set,
+ .pinconf_num_params = ARRAY_SIZE(stmfx_pinctrl_conf_params),
+ .pinconf_params = stmfx_pinctrl_conf_params,
+#endif
+};
+
+static const struct udevice_id stmfx_pinctrl_match[] = {
+ { .compatible = "st,stmfx-0300-pinctrl", },
+};
+
+U_BOOT_DRIVER(stmfx_pinctrl) = {
+ .name = "stmfx-pinctrl",
+ .id = UCLASS_PINCTRL,
+ .of_match = of_match_ptr(stmfx_pinctrl_match),
+ .bind = stmfx_pinctrl_bind,
+ .probe = stmfx_pinctrl_probe,
+ .ops = &stmfx_pinctrl_ops,
+ .platdata_auto_alloc_size = sizeof(struct stmfx_pinctrl),
+};
+
+static int stmfx_chip_init(struct udevice *dev)
+{
+ u8 id;
+ u8 version[2];
+ int ret;
+ struct dm_i2c_chip *chip = dev_get_parent_platdata(dev);
+
+ id = dm_i2c_reg_read(dev, STMFX_REG_CHIP_ID);
+ if (id < 0) {
+ dev_err(dev, "error reading chip id: %d\n", id);
+ return ret;
+ }
+ /*
+ * Check that ID is the complement of the I2C address:
+ * STMFX I2C address follows the 7-bit format (MSB), that's why
+ * client->addr is shifted.
+ *
+ * STMFX_I2C_ADDR| STMFX | Linux
+ * input pin | I2C device address | I2C device address
+ *---------------------------------------------------------
+ * 0 | b: 1000 010x h:0x84 | 0x42
+ * 1 | b: 1000 011x h:0x86 | 0x43
+ */
+ if (FIELD_GET(STMFX_REG_CHIP_ID_MASK, ~id) != (chip->chip_addr << 1)) {
+ dev_err(dev, "unknown chip id: %#x\n", id);
+ return -EINVAL;
+ }
+
+ ret = dm_i2c_read(dev, STMFX_REG_FW_VERSION_MSB,
+ version, sizeof(version));
+ if (ret) {
+ dev_err(dev, "error reading fw version: %d\n", ret);
+ return ret;
+ }
+
+ dev_info(dev, "STMFX id: %#x, fw version: %x.%02x\n",
+ id, version[0], version[1]);
+
+ ret = dm_i2c_reg_read(dev, STMFX_REG_SYS_CTRL);
+
+ if (ret < 0)
+ return ret;
+
+ ret = dm_i2c_reg_write(dev, STMFX_REG_SYS_CTRL,
+ ret | STMFX_REG_SYS_CTRL_SWRST);
+ if (ret)
+ return ret;
+
+ mdelay(STMFX_BOOT_TIME_MS);
+
+ return ret;
+}
+
+static int stmfx_probe(struct udevice *dev)
+{
+ struct udevice *vdd;
+ int ret;
+
+ ret = device_get_supply_regulator(dev, "vdd-supply", &vdd);
+ if (ret && ret != -ENOENT) {
+ dev_err(dev, "vdd regulator error:%d\n", ret);
+ return ret;
+ }
+ if (!ret) {
+ ret = regulator_set_enable(vdd, true);
+ if (ret) {
+ dev_err(dev, "vdd enable failed: %d\n", ret);
+ return ret;
+ }
+ }
+
+ return stmfx_chip_init(dev);
+}
+
+static const struct udevice_id stmfx_match[] = {
+ { .compatible = "st,stmfx-0300", },
+};
+
+U_BOOT_DRIVER(stmfx) = {
+ .name = "stmfx",
+ .id = UCLASS_I2C_GENERIC,
+ .of_match = of_match_ptr(stmfx_match),
+ .probe = stmfx_probe,
+ .bind = dm_scan_fdt_dev,
+};