| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Driver for TWL4030/6030 Pulse Width Modulator used as LED driver |
| * |
| * Copyright (C) 2012 Texas Instruments |
| * Author: Peter Ujfalusi <peter.ujfalusi@ti.com> |
| * |
| * This driver is a complete rewrite of the former pwm-twl6030.c authorded by: |
| * Hemanth V <hemanthv@ti.com> |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/of.h> |
| #include <linux/platform_device.h> |
| #include <linux/pwm.h> |
| #include <linux/mfd/twl.h> |
| #include <linux/slab.h> |
| |
| /* |
| * This driver handles the PWM driven LED terminals of TWL4030 and TWL6030. |
| * To generate the signal on TWL4030: |
| * - LEDA uses PWMA |
| * - LEDB uses PWMB |
| * TWL6030 has one LED pin with dedicated LEDPWM |
| */ |
| |
| #define TWL4030_LED_MAX 0x7f |
| #define TWL6030_LED_MAX 0xff |
| |
| /* Registers, bits and macro for TWL4030 */ |
| #define TWL4030_LEDEN_REG 0x00 |
| #define TWL4030_PWMA_REG 0x01 |
| |
| #define TWL4030_LEDXON (1 << 0) |
| #define TWL4030_LEDXPWM (1 << 4) |
| #define TWL4030_LED_PINS (TWL4030_LEDXON | TWL4030_LEDXPWM) |
| #define TWL4030_LED_TOGGLE(led, x) ((x) << (led)) |
| |
| /* Register, bits and macro for TWL6030 */ |
| #define TWL6030_LED_PWM_CTRL1 0xf4 |
| #define TWL6030_LED_PWM_CTRL2 0xf5 |
| |
| #define TWL6040_LED_MODE_HW 0x00 |
| #define TWL6040_LED_MODE_ON 0x01 |
| #define TWL6040_LED_MODE_OFF 0x02 |
| #define TWL6040_LED_MODE_MASK 0x03 |
| |
| struct twl_pwmled_chip { |
| struct pwm_chip chip; |
| struct mutex mutex; |
| }; |
| |
| static inline struct twl_pwmled_chip *to_twl(struct pwm_chip *chip) |
| { |
| return container_of(chip, struct twl_pwmled_chip, chip); |
| } |
| |
| static int twl4030_pwmled_config(struct pwm_chip *chip, struct pwm_device *pwm, |
| int duty_ns, int period_ns) |
| { |
| int duty_cycle = DIV_ROUND_UP(duty_ns * TWL4030_LED_MAX, period_ns) + 1; |
| u8 pwm_config[2] = { 1, 0 }; |
| int base, ret; |
| |
| /* |
| * To configure the duty period: |
| * On-cycle is set to 1 (the minimum allowed value) |
| * The off time of 0 is not configurable, so the mapping is: |
| * 0 -> off cycle = 2, |
| * 1 -> off cycle = 2, |
| * 2 -> off cycle = 3, |
| * 126 - > off cycle 127, |
| * 127 - > off cycle 1 |
| * When on cycle == off cycle the PWM will be always on |
| */ |
| if (duty_cycle == 1) |
| duty_cycle = 2; |
| else if (duty_cycle > TWL4030_LED_MAX) |
| duty_cycle = 1; |
| |
| base = pwm->hwpwm * 2 + TWL4030_PWMA_REG; |
| |
| pwm_config[1] = duty_cycle; |
| |
| ret = twl_i2c_write(TWL4030_MODULE_LED, pwm_config, base, 2); |
| if (ret < 0) |
| dev_err(chip->dev, "%s: Failed to configure PWM\n", pwm->label); |
| |
| return ret; |
| } |
| |
| static int twl4030_pwmled_enable(struct pwm_chip *chip, struct pwm_device *pwm) |
| { |
| struct twl_pwmled_chip *twl = to_twl(chip); |
| int ret; |
| u8 val; |
| |
| mutex_lock(&twl->mutex); |
| ret = twl_i2c_read_u8(TWL4030_MODULE_LED, &val, TWL4030_LEDEN_REG); |
| if (ret < 0) { |
| dev_err(chip->dev, "%s: Failed to read LEDEN\n", pwm->label); |
| goto out; |
| } |
| |
| val |= TWL4030_LED_TOGGLE(pwm->hwpwm, TWL4030_LED_PINS); |
| |
| ret = twl_i2c_write_u8(TWL4030_MODULE_LED, val, TWL4030_LEDEN_REG); |
| if (ret < 0) |
| dev_err(chip->dev, "%s: Failed to enable PWM\n", pwm->label); |
| |
| out: |
| mutex_unlock(&twl->mutex); |
| return ret; |
| } |
| |
| static void twl4030_pwmled_disable(struct pwm_chip *chip, |
| struct pwm_device *pwm) |
| { |
| struct twl_pwmled_chip *twl = to_twl(chip); |
| int ret; |
| u8 val; |
| |
| mutex_lock(&twl->mutex); |
| ret = twl_i2c_read_u8(TWL4030_MODULE_LED, &val, TWL4030_LEDEN_REG); |
| if (ret < 0) { |
| dev_err(chip->dev, "%s: Failed to read LEDEN\n", pwm->label); |
| goto out; |
| } |
| |
| val &= ~TWL4030_LED_TOGGLE(pwm->hwpwm, TWL4030_LED_PINS); |
| |
| ret = twl_i2c_write_u8(TWL4030_MODULE_LED, val, TWL4030_LEDEN_REG); |
| if (ret < 0) |
| dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label); |
| |
| out: |
| mutex_unlock(&twl->mutex); |
| } |
| |
| static int twl4030_pwmled_apply(struct pwm_chip *chip, struct pwm_device *pwm, |
| const struct pwm_state *state) |
| { |
| int ret; |
| |
| if (state->polarity != PWM_POLARITY_NORMAL) |
| return -EINVAL; |
| |
| if (!state->enabled) { |
| if (pwm->state.enabled) |
| twl4030_pwmled_disable(chip, pwm); |
| |
| return 0; |
| } |
| |
| /* |
| * We cannot skip calling ->config even if state->period == |
| * pwm->state.period && state->duty_cycle == pwm->state.duty_cycle |
| * because we might have exited early in the last call to |
| * pwm_apply_state because of !state->enabled and so the two values in |
| * pwm->state might not be configured in hardware. |
| */ |
| ret = twl4030_pwmled_config(pwm->chip, pwm, |
| state->duty_cycle, state->period); |
| if (ret) |
| return ret; |
| |
| if (!pwm->state.enabled) |
| ret = twl4030_pwmled_enable(chip, pwm); |
| |
| return ret; |
| } |
| |
| |
| static const struct pwm_ops twl4030_pwmled_ops = { |
| .apply = twl4030_pwmled_apply, |
| .owner = THIS_MODULE, |
| }; |
| |
| static int twl6030_pwmled_config(struct pwm_chip *chip, struct pwm_device *pwm, |
| int duty_ns, int period_ns) |
| { |
| int duty_cycle = (duty_ns * TWL6030_LED_MAX) / period_ns; |
| u8 on_time; |
| int ret; |
| |
| on_time = duty_cycle & 0xff; |
| |
| ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, on_time, |
| TWL6030_LED_PWM_CTRL1); |
| if (ret < 0) |
| dev_err(chip->dev, "%s: Failed to configure PWM\n", pwm->label); |
| |
| return ret; |
| } |
| |
| static int twl6030_pwmled_enable(struct pwm_chip *chip, struct pwm_device *pwm) |
| { |
| struct twl_pwmled_chip *twl = to_twl(chip); |
| int ret; |
| u8 val; |
| |
| mutex_lock(&twl->mutex); |
| ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, TWL6030_LED_PWM_CTRL2); |
| if (ret < 0) { |
| dev_err(chip->dev, "%s: Failed to read PWM_CTRL2\n", |
| pwm->label); |
| goto out; |
| } |
| |
| val &= ~TWL6040_LED_MODE_MASK; |
| val |= TWL6040_LED_MODE_ON; |
| |
| ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_LED_PWM_CTRL2); |
| if (ret < 0) |
| dev_err(chip->dev, "%s: Failed to enable PWM\n", pwm->label); |
| |
| out: |
| mutex_unlock(&twl->mutex); |
| return ret; |
| } |
| |
| static void twl6030_pwmled_disable(struct pwm_chip *chip, |
| struct pwm_device *pwm) |
| { |
| struct twl_pwmled_chip *twl = to_twl(chip); |
| int ret; |
| u8 val; |
| |
| mutex_lock(&twl->mutex); |
| ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, TWL6030_LED_PWM_CTRL2); |
| if (ret < 0) { |
| dev_err(chip->dev, "%s: Failed to read PWM_CTRL2\n", |
| pwm->label); |
| goto out; |
| } |
| |
| val &= ~TWL6040_LED_MODE_MASK; |
| val |= TWL6040_LED_MODE_OFF; |
| |
| ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_LED_PWM_CTRL2); |
| if (ret < 0) |
| dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label); |
| |
| out: |
| mutex_unlock(&twl->mutex); |
| } |
| |
| static int twl6030_pwmled_apply(struct pwm_chip *chip, struct pwm_device *pwm, |
| const struct pwm_state *state) |
| { |
| int err; |
| |
| if (state->polarity != pwm->state.polarity) |
| return -EINVAL; |
| |
| if (!state->enabled) { |
| if (pwm->state.enabled) |
| twl6030_pwmled_disable(chip, pwm); |
| |
| return 0; |
| } |
| |
| err = twl6030_pwmled_config(pwm->chip, pwm, |
| state->duty_cycle, state->period); |
| if (err) |
| return err; |
| |
| if (!pwm->state.enabled) |
| err = twl6030_pwmled_enable(chip, pwm); |
| |
| return err; |
| } |
| |
| static int twl6030_pwmled_request(struct pwm_chip *chip, struct pwm_device *pwm) |
| { |
| struct twl_pwmled_chip *twl = to_twl(chip); |
| int ret; |
| u8 val; |
| |
| mutex_lock(&twl->mutex); |
| ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, TWL6030_LED_PWM_CTRL2); |
| if (ret < 0) { |
| dev_err(chip->dev, "%s: Failed to read PWM_CTRL2\n", |
| pwm->label); |
| goto out; |
| } |
| |
| val &= ~TWL6040_LED_MODE_MASK; |
| val |= TWL6040_LED_MODE_OFF; |
| |
| ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_LED_PWM_CTRL2); |
| if (ret < 0) |
| dev_err(chip->dev, "%s: Failed to request PWM\n", pwm->label); |
| |
| out: |
| mutex_unlock(&twl->mutex); |
| return ret; |
| } |
| |
| static void twl6030_pwmled_free(struct pwm_chip *chip, struct pwm_device *pwm) |
| { |
| struct twl_pwmled_chip *twl = to_twl(chip); |
| int ret; |
| u8 val; |
| |
| mutex_lock(&twl->mutex); |
| ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, TWL6030_LED_PWM_CTRL2); |
| if (ret < 0) { |
| dev_err(chip->dev, "%s: Failed to read PWM_CTRL2\n", |
| pwm->label); |
| goto out; |
| } |
| |
| val &= ~TWL6040_LED_MODE_MASK; |
| val |= TWL6040_LED_MODE_HW; |
| |
| ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_LED_PWM_CTRL2); |
| if (ret < 0) |
| dev_err(chip->dev, "%s: Failed to free PWM\n", pwm->label); |
| |
| out: |
| mutex_unlock(&twl->mutex); |
| } |
| |
| static const struct pwm_ops twl6030_pwmled_ops = { |
| .apply = twl6030_pwmled_apply, |
| .request = twl6030_pwmled_request, |
| .free = twl6030_pwmled_free, |
| .owner = THIS_MODULE, |
| }; |
| |
| static int twl_pwmled_probe(struct platform_device *pdev) |
| { |
| struct twl_pwmled_chip *twl; |
| |
| twl = devm_kzalloc(&pdev->dev, sizeof(*twl), GFP_KERNEL); |
| if (!twl) |
| return -ENOMEM; |
| |
| if (twl_class_is_4030()) { |
| twl->chip.ops = &twl4030_pwmled_ops; |
| twl->chip.npwm = 2; |
| } else { |
| twl->chip.ops = &twl6030_pwmled_ops; |
| twl->chip.npwm = 1; |
| } |
| |
| twl->chip.dev = &pdev->dev; |
| |
| mutex_init(&twl->mutex); |
| |
| return devm_pwmchip_add(&pdev->dev, &twl->chip); |
| } |
| |
| #ifdef CONFIG_OF |
| static const struct of_device_id twl_pwmled_of_match[] = { |
| { .compatible = "ti,twl4030-pwmled" }, |
| { .compatible = "ti,twl6030-pwmled" }, |
| { }, |
| }; |
| MODULE_DEVICE_TABLE(of, twl_pwmled_of_match); |
| #endif |
| |
| static struct platform_driver twl_pwmled_driver = { |
| .driver = { |
| .name = "twl-pwmled", |
| .of_match_table = of_match_ptr(twl_pwmled_of_match), |
| }, |
| .probe = twl_pwmled_probe, |
| }; |
| module_platform_driver(twl_pwmled_driver); |
| |
| MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>"); |
| MODULE_DESCRIPTION("PWM driver for TWL4030 and TWL6030 LED outputs"); |
| MODULE_ALIAS("platform:twl-pwmled"); |
| MODULE_LICENSE("GPL"); |