--- /dev/null
+/*
+ * 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/of.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 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");
Code Review / kvmfornfv.git / blobdiff