/* * Driver for TWL4030/6030 Pulse Width Modulator used as LED driver * * Copyright (C) 2012 Texas Instruments * Author: Peter Ujfalusi * * This driver is a complete rewrite of the former pwm-twl6030.c authorded by: * Hemanth V * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published by * the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License along with * this program. If not, see . */ #include #include #include #include #include #include /* * 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 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_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 twl4030_pwmled_ops = { .enable = twl4030_pwmled_enable, .disable = twl4030_pwmled_disable, .config = twl4030_pwmled_config, .owner = THIS_MODULE, }; static const struct pwm_ops twl6030_pwmled_ops = { .enable = twl6030_pwmled_enable, .disable = twl6030_pwmled_disable, .config = twl6030_pwmled_config, .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; int ret; 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; twl->chip.base = -1; twl->chip.can_sleep = true; mutex_init(&twl->mutex); ret = pwmchip_add(&twl->chip); if (ret < 0) return ret; platform_set_drvdata(pdev, twl); return 0; } static int twl_pwmled_remove(struct platform_device *pdev) { struct twl_pwmled_chip *twl = platform_get_drvdata(pdev); return pwmchip_remove(&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, .remove = twl_pwmled_remove, }; module_platform_driver(twl_pwmled_driver); MODULE_AUTHOR("Peter Ujfalusi "); MODULE_DESCRIPTION("PWM driver for TWL4030 and TWL6030 LED outputs"); MODULE_ALIAS("platform:twl-pwmled"); MODULE_LICENSE("GPL");