/* * Driver for TWL4030/6030 Generic Pulse Width Modulator * * Copyright (C) 2012 Texas Instruments * Author: Peter Ujfalusi <peter.ujfalusi@ti.com> * * 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 <http://www.gnu.org/licenses/>. */ #include <linux/module.h> #include <linux/platform_device.h> #include <linux/pwm.h> #include <linux/i2c/twl.h> #include <linux/slab.h> /* * This driver handles the PWMs of TWL4030 and TWL6030. * The TRM names for the PWMs on TWL4030 are: PWM0, PWM1 * TWL6030 also have two PWMs named in the TRM as PWM1, PWM2 */ #define TWL_PWM_MAX 0x7f /* Registers, bits and macro for TWL4030 */ #define TWL4030_GPBR1_REG 0x0c #define TWL4030_PMBR1_REG 0x0d /* GPBR1 register bits */ #define TWL4030_PWMXCLK_ENABLE (1 << 0) #define TWL4030_PWMX_ENABLE (1 << 2) #define TWL4030_PWMX_BITS (TWL4030_PWMX_ENABLE | TWL4030_PWMXCLK_ENABLE) #define TWL4030_PWM_TOGGLE(pwm, x) ((x) << (pwm)) /* PMBR1 register bits */ #define TWL4030_GPIO6_PWM0_MUTE_MASK (0x03 << 2) #define TWL4030_GPIO6_PWM0_MUTE_PWM0 (0x01 << 2) #define TWL4030_GPIO7_VIBRASYNC_PWM1_MASK (0x03 << 4) #define TWL4030_GPIO7_VIBRASYNC_PWM1_PWM1 (0x03 << 4) /* Register, bits and macro for TWL6030 */ #define TWL6030_TOGGLE3_REG 0x92 #define TWL6030_PWMXR (1 << 0) #define TWL6030_PWMXS (1 << 1) #define TWL6030_PWMXEN (1 << 2) #define TWL6030_PWM_TOGGLE(pwm, x) ((x) << (pwm * 3)) struct twl_pwm_chip { struct pwm_chip chip; struct mutex mutex; u8 twl6030_toggle3; u8 twl4030_pwm_mux; }; static inline struct twl_pwm_chip *to_twl(struct pwm_chip *chip) { return container_of(chip, struct twl_pwm_chip, chip); } static int twl_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns) { int duty_cycle = DIV_ROUND_UP(duty_ns * TWL_PWM_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 > TWL_PWM_MAX) duty_cycle = 1; base = pwm->hwpwm * 3; pwm_config[1] = duty_cycle; ret = twl_i2c_write(TWL_MODULE_PWM, pwm_config, base, 2); if (ret < 0) dev_err(chip->dev, "%s: Failed to configure PWM\n", pwm->label); return ret; } static int twl4030_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) { struct twl_pwm_chip *twl = to_twl(chip); int ret; u8 val; mutex_lock(&twl->mutex); ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_GPBR1_REG); if (ret < 0) { dev_err(chip->dev, "%s: Failed to read GPBR1\n", pwm->label); goto out; } val |= TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMXCLK_ENABLE); ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_REG); if (ret < 0) dev_err(chip->dev, "%s: Failed to enable PWM\n", pwm->label); val |= TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMX_ENABLE); ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_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_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) { struct twl_pwm_chip *twl = to_twl(chip); int ret; u8 val; mutex_lock(&twl->mutex); ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_GPBR1_REG); if (ret < 0) { dev_err(chip->dev, "%s: Failed to read GPBR1\n", pwm->label); goto out; } val &= ~TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMX_ENABLE); ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_REG); if (ret < 0) dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label); val &= ~TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMXCLK_ENABLE); ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_REG); if (ret < 0) dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label); out: mutex_unlock(&twl->mutex); } static int twl4030_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) { struct twl_pwm_chip *twl = to_twl(chip); int ret; u8 val, mask, bits; if (pwm->hwpwm == 1) { mask = TWL4030_GPIO7_VIBRASYNC_PWM1_MASK; bits = TWL4030_GPIO7_VIBRASYNC_PWM1_PWM1; } else { mask = TWL4030_GPIO6_PWM0_MUTE_MASK; bits = TWL4030_GPIO6_PWM0_MUTE_PWM0; } mutex_lock(&twl->mutex); ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_PMBR1_REG); if (ret < 0) { dev_err(chip->dev, "%s: Failed to read PMBR1\n", pwm->label); goto out; } /* Save the current MUX configuration for the PWM */ twl->twl4030_pwm_mux &= ~mask; twl->twl4030_pwm_mux |= (val & mask); /* Select PWM functionality */ val &= ~mask; val |= bits; ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_PMBR1_REG); if (ret < 0) dev_err(chip->dev, "%s: Failed to request PWM\n", pwm->label); out: mutex_unlock(&twl->mutex); return ret; } static void twl4030_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) { struct twl_pwm_chip *twl = to_twl(chip); int ret; u8 val, mask; if (pwm->hwpwm == 1) mask = TWL4030_GPIO7_VIBRASYNC_PWM1_MASK; else mask = TWL4030_GPIO6_PWM0_MUTE_MASK; mutex_lock(&twl->mutex); ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_PMBR1_REG); if (ret < 0) { dev_err(chip->dev, "%s: Failed to read PMBR1\n", pwm->label); goto out; } /* Restore the MUX configuration for the PWM */ val &= ~mask; val |= (twl->twl4030_pwm_mux & mask); ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_PMBR1_REG); if (ret < 0) dev_err(chip->dev, "%s: Failed to free PWM\n", pwm->label); out: mutex_unlock(&twl->mutex); } static int twl6030_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) { struct twl_pwm_chip *twl = to_twl(chip); int ret; u8 val; mutex_lock(&twl->mutex); val = twl->twl6030_toggle3; val |= TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXS | TWL6030_PWMXEN); val &= ~TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXR); ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_TOGGLE3_REG); if (ret < 0) { dev_err(chip->dev, "%s: Failed to enable PWM\n", pwm->label); goto out; } twl->twl6030_toggle3 = val; out: mutex_unlock(&twl->mutex); return ret; } static void twl6030_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) { struct twl_pwm_chip *twl = to_twl(chip); int ret; u8 val; mutex_lock(&twl->mutex); val = twl->twl6030_toggle3; val |= TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXR); val &= ~TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXS | TWL6030_PWMXEN); ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_TOGGLE3_REG); if (ret < 0) { dev_err(chip->dev, "%s: Failed to read TOGGLE3\n", pwm->label); goto out; } val |= TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXS | TWL6030_PWMXEN); ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_TOGGLE3_REG); if (ret < 0) { dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label); goto out; } twl->twl6030_toggle3 = val; out: mutex_unlock(&twl->mutex); } static const struct pwm_ops twl4030_pwm_ops = { .config = twl_pwm_config, .enable = twl4030_pwm_enable, .disable = twl4030_pwm_disable, .request = twl4030_pwm_request, .free = twl4030_pwm_free, .owner = THIS_MODULE, }; static const struct pwm_ops twl6030_pwm_ops = { .config = twl_pwm_config, .enable = twl6030_pwm_enable, .disable = twl6030_pwm_disable, .owner = THIS_MODULE, }; static int twl_pwm_probe(struct platform_device *pdev) { struct twl_pwm_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_pwm_ops; else twl->chip.ops = &twl6030_pwm_ops; twl->chip.dev = &pdev->dev; twl->chip.base = -1; twl->chip.npwm = 2; 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_pwm_remove(struct platform_device *pdev) { struct twl_pwm_chip *twl = platform_get_drvdata(pdev); return pwmchip_remove(&twl->chip); } #ifdef CONFIG_OF static const struct of_device_id twl_pwm_of_match[] = { { .compatible = "ti,twl4030-pwm" }, { .compatible = "ti,twl6030-pwm" }, { }, }; MODULE_DEVICE_TABLE(of, twl_pwm_of_match); #endif static struct platform_driver twl_pwm_driver = { .driver = { .name = "twl-pwm", .of_match_table = of_match_ptr(twl_pwm_of_match), }, .probe = twl_pwm_probe, .remove = twl_pwm_remove, }; module_platform_driver(twl_pwm_driver); MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>"); MODULE_DESCRIPTION("PWM driver for TWL4030 and TWL6030"); MODULE_ALIAS("platform:twl-pwm"); MODULE_LICENSE("GPL");