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drivers: pwm: it8801: Add I2C-based PWM device driver
Add I2C-based PWM device driver. Supports 7 open-drain/push-pull outputs. Signed-off-by: Tim Lin <[email protected]>
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‎drivers/pwm/CMakeLists.txt‎

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@@ -13,6 +13,7 @@ zephyr_library_sources_ifdef(CONFIG_PWM_NRFX pwm_nrfx.c)
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zephyr_library_sources_ifdef(CONFIG_PWM_MCUX_FTM pwm_mcux_ftm.c)
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zephyr_library_sources_ifdef(CONFIG_PWM_IMX pwm_imx.c)
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zephyr_library_sources_ifdef(CONFIG_PWM_ITE_IT8XXX2 pwm_ite_it8xxx2.c)
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zephyr_library_sources_ifdef(CONFIG_PWM_ITE_IT8801 pwm_ite_it8801.c)
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zephyr_library_sources_ifdef(CONFIG_PWM_LED_ESP32 pwm_led_esp32.c)
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zephyr_library_sources_ifdef(CONFIG_MCPWM_ESP32 pwm_mc_esp32.c)
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zephyr_library_sources_ifdef(CONFIG_PWM_SAM pwm_sam.c)

‎drivers/pwm/Kconfig‎

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@@ -50,6 +50,8 @@ source "drivers/pwm/Kconfig.imx"
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source "drivers/pwm/Kconfig.it8xxx2"
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source "drivers/pwm/Kconfig.it8801"
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source "drivers/pwm/Kconfig.esp32"
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source "drivers/pwm/Kconfig.sam"

‎drivers/pwm/Kconfig.it8801‎

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# Copyright (c) 2024 ITE Corporation. All Rights Reserved.
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# SPDX-License-Identifier: Apache-2.0
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config PWM_ITE_IT8801
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bool "ITE IT8801 PWM device driver"
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default y
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depends on DT_HAS_ITE_IT8801_PWM_ENABLED
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select I2C
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select MFD
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help
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Enable driver for ITE IT8801 I2C-based PWM.
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Supports 7 open-drain/push-pull outputs.

‎drivers/pwm/pwm_ite_it8801.c‎

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/*
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* Copyright (c) 2024 ITE Corporation. All Rights Reserved.
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*
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* SPDX-License-Identifier: Apache-2.0
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*/
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#define DT_DRV_COMPAT ite_it8801_pwm
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#include <zephyr/device.h>
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#include <zephyr/drivers/i2c.h>
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#include <zephyr/drivers/mfd/mfd_ite_it8801.h>
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#include <zephyr/drivers/pwm.h>
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#include <zephyr/logging/log.h>
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LOG_MODULE_REGISTER(pwm_ite_it8801, CONFIG_PWM_LOG_LEVEL);
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struct it8801_pwm_map {
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uint8_t pushpull_en;
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};
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const static struct it8801_pwm_map it8801_pwm_gpio_map[] = {
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[1] = {.pushpull_en = BIT(0)}, [2] = {.pushpull_en = BIT(1)}, [3] = {.pushpull_en = BIT(2)},
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[4] = {.pushpull_en = BIT(3)}, [7] = {.pushpull_en = BIT(4)}, [8] = {.pushpull_en = BIT(5)},
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[9] = {.pushpull_en = BIT(6)},
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};
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struct it8801_mfd_pwm_altctrl_cfg {
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/* GPIO control device structure */
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const struct device *gpiocr;
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/* GPIO control pin */
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uint8_t pin;
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/* GPIO function select */
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uint8_t alt_func;
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};
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struct pwm_it8801_config {
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/* IT8801 controller dev */
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const struct device *mfd;
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/* I2C device for the MFD parent */
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const struct i2c_dt_spec i2c_dev;
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/* PWM alternate configuration */
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const struct it8801_mfd_pwm_altctrl_cfg *altctrl;
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int mfdctrl_len;
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int channel;
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/* PWM mode control register */
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uint8_t reg_mcr;
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/* PWM duty cycle register */
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uint8_t reg_dcr;
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/* PWM prescale LSB register */
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uint8_t reg_prslr;
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/* PWM prescale MSB register */
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uint8_t reg_prsmr;
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};
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static void pwm_enable(const struct device *dev, int enabled)
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{
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const struct pwm_it8801_config *config = dev->config;
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int ret;
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if (enabled) {
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ret = i2c_reg_update_byte_dt(&config->i2c_dev, config->reg_mcr,
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IT8801_PWMMCR_MCR_MASK, IT8801_PWMMCR_MCR_BLINKING);
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} else {
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ret = i2c_reg_update_byte_dt(&config->i2c_dev, config->reg_mcr,
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IT8801_PWMMCR_MCR_MASK, 0);
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}
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if (ret != 0) {
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LOG_ERR("Failed to enable pwm (ret %d)", ret);
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return;
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}
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}
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static int pwm_it8801_get_cycles_per_sec(const struct device *dev, uint32_t channel,
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uint64_t *cycles)
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{
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ARG_UNUSED(dev);
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ARG_UNUSED(channel);
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*cycles = (uint64_t)PWM_IT8801_FREQ;
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return 0;
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}
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static int pwm_it8801_set_cycles(const struct device *dev, uint32_t channel, uint32_t period_cycles,
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uint32_t pulse_cycles, pwm_flags_t flags)
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{
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ARG_UNUSED(channel);
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const struct pwm_it8801_config *config = dev->config;
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int ch = config->channel, ret;
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uint8_t duty, mask;
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/* Enable PWM output push-pull */
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if (flags & PWM_IT8801_PUSH_PULL) {
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mask = it8801_pwm_gpio_map[ch].pushpull_en;
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ret = i2c_reg_update_byte_dt(&config->i2c_dev, IT8801_REG_PWMODDSR, mask, mask);
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if (ret != 0) {
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LOG_ERR("Failed to set push-pull (ret %d)", ret);
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return ret;
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}
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}
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/* Set PWM channel duty cycle */
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if (pulse_cycles == 0) {
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duty = 0;
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} else {
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duty = pulse_cycles * 256 / period_cycles - 1;
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}
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LOG_DBG("IT8801 pwm duty cycles = %d", duty);
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ret = i2c_reg_write_byte_dt(&config->i2c_dev, config->reg_dcr, duty);
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if (ret != 0) {
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LOG_ERR("Failed to set cycles (ret %d)", ret);
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return ret;
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}
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/* PWM channel clock source not gating */
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pwm_enable(dev, 1);
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return 0;
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}
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static int pwm_it8801_init(const struct device *dev)
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{
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const struct pwm_it8801_config *config = dev->config;
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int ret;
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/* Verify multi-function parent is ready */
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if (!device_is_ready(config->mfd)) {
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LOG_ERR("(pwm)%s is not ready", config->mfd->name);
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return -ENODEV;
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}
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/* PWM channel clock source gating before configuring */
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pwm_enable(dev, 0);
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for (int i = 0; i < config->mfdctrl_len; i++) {
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/* Switching the pin to PWM alternate function */
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ret = mfd_it8801_configure_pins(&config->i2c_dev, config->altctrl[i].gpiocr,
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config->altctrl[i].pin,
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config->altctrl[i].alt_func);
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if (ret != 0) {
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LOG_ERR("Failed to configure pins (ret %d)", ret);
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return ret;
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}
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}
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return 0;
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}
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static const struct pwm_driver_api pwm_it8801_api = {
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.set_cycles = pwm_it8801_set_cycles,
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.get_cycles_per_sec = pwm_it8801_get_cycles_per_sec,
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};
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#define PWM_IT8801_INIT(inst) \
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static const struct it8801_mfd_pwm_altctrl_cfg \
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it8801_pwm_altctrl##inst[IT8801_DT_INST_MFDCTRL_LEN(inst)] = \
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IT8801_DT_MFD_ITEMS_LIST(inst); \
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static const struct pwm_it8801_config pwm_it8801_cfg_##inst = { \
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.mfd = DEVICE_DT_GET(DT_INST_PARENT(inst)), \
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.i2c_dev = I2C_DT_SPEC_GET(DT_INST_PARENT(inst)), \
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.altctrl = it8801_pwm_altctrl##inst, \
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.mfdctrl_len = IT8801_DT_INST_MFDCTRL_LEN(inst), \
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.channel = DT_INST_PROP(inst, channel), \
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.reg_mcr = DT_INST_REG_ADDR_BY_IDX(inst, 0), \
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.reg_dcr = DT_INST_REG_ADDR_BY_IDX(inst, 1), \
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.reg_prslr = DT_INST_REG_ADDR_BY_IDX(inst, 2), \
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.reg_prsmr = DT_INST_REG_ADDR_BY_IDX(inst, 3), \
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}; \
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DEVICE_DT_INST_DEFINE(inst, &pwm_it8801_init, NULL, NULL, &pwm_it8801_cfg_##inst, \
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POST_KERNEL, CONFIG_MFD_INIT_PRIORITY, &pwm_it8801_api);
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DT_INST_FOREACH_STATUS_OKAY(PWM_IT8801_INIT)

‎dts/bindings/pwm/ite,it8801-pwm.yaml‎

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# Copyright (c) 2024 ITE Corporation. All Rights Reserved.
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# SPDX-License-Identifier: Apache-2.0
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description: ITE IT8801 I2C-based PWM device driver
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compatible: "ite,it8801-pwm"
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include: [base.yaml, pinctrl-device.yaml, pwm-controller.yaml]
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properties:
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reg:
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required: true
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mfdctrl:
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type: phandle
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required: true
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description: |
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Switching the pin to PWM alternate function.
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channel:
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type: int
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required: true
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enum:
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- 1
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- 2
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- 3
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- 4
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- 7
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- 8
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- 9
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description: |
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1 = PWM_CHANNEL_1, 2 = PWM_CHANNEL_2, 3 = PWM_CHANNEL_3,
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4 = PWM_CHANNEL_4, 7 = PWM_CHANNEL_7, 8 = PWM_CHANNEL_8,
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9 = PWM_CHANNEL_9
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pwm-cells:
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- channel
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- period
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- flags

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