[deliverable/linux.git] / drivers / pwm / pwm-twl6030.c

/*
 * twl6030_pwm.c
 * Driver for PHOENIX (TWL6030) Pulse Width Modulator
 *
 * Copyright (C) 2010 Texas Instruments
 * Author: Hemanth V <hemanthv@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>

#define LED_PWM_CTRL1	0xF4
#define LED_PWM_CTRL2	0xF5

/* Max value for CTRL1 register */
#define PWM_CTRL1_MAX	255

/* Pull down disable */
#define PWM_CTRL2_DIS_PD	(1 << 6)

/* Current control 2.5 milli Amps */
#define PWM_CTRL2_CURR_02	(2 << 4)

/* LED supply source */
#define PWM_CTRL2_SRC_VAC	(1 << 2)

/* LED modes */
#define PWM_CTRL2_MODE_HW	(0 << 0)
#define PWM_CTRL2_MODE_SW	(1 << 0)
#define PWM_CTRL2_MODE_DIS	(2 << 0)

#define PWM_CTRL2_MODE_MASK	0x3

struct twl6030_pwm_chip {
	struct pwm_chip chip;
};

static int twl6030_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
{
	int ret;
	u8 val;

	/* Configure PWM */
	val = PWM_CTRL2_DIS_PD | PWM_CTRL2_CURR_02 | PWM_CTRL2_SRC_VAC |
	      PWM_CTRL2_MODE_HW;

	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, LED_PWM_CTRL2);
	if (ret < 0) {
		dev_err(chip->dev, "%s: Failed to configure PWM, Error %d\n",
			pwm->label, ret);
		return ret;
	}

	return 0;
}

static int twl6030_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
			      int duty_ns, int period_ns)
{
	u8 duty_cycle = (duty_ns * PWM_CTRL1_MAX) / period_ns;
	int ret;

	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, duty_cycle, LED_PWM_CTRL1);
	if (ret < 0) {
		pr_err("%s: Failed to configure PWM, Error %d\n",
			pwm->label, ret);
		return ret;
	}

	return 0;
}

static int twl6030_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
	int ret;
	u8 val;

	ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, LED_PWM_CTRL2);
	if (ret < 0) {
		dev_err(chip->dev, "%s: Failed to enable PWM, Error %d\n",
			pwm->label, ret);
		return ret;
	}

	/* Change mode to software control */
	val &= ~PWM_CTRL2_MODE_MASK;
	val |= PWM_CTRL2_MODE_SW;

	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, LED_PWM_CTRL2);
	if (ret < 0) {
		dev_err(chip->dev, "%s: Failed to enable PWM, Error %d\n",
			pwm->label, ret);
		return ret;
	}

	twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, LED_PWM_CTRL2);
	return 0;
}

static void twl6030_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
	int ret;
	u8 val;

	ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, LED_PWM_CTRL2);
	if (ret < 0) {
		dev_err(chip->dev, "%s: Failed to disable PWM, Error %d\n",
			pwm->label, ret);
		return;
	}

	val &= ~PWM_CTRL2_MODE_MASK;
	val |= PWM_CTRL2_MODE_HW;

	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, LED_PWM_CTRL2);
	if (ret < 0) {
		dev_err(chip->dev, "%s: Failed to disable PWM, Error %d\n",
			pwm->label, ret);
	}
}

static const struct pwm_ops twl6030_pwm_ops = {
	.request = twl6030_pwm_request,
	.config = twl6030_pwm_config,
	.enable = twl6030_pwm_enable,
	.disable = twl6030_pwm_disable,
};

static int twl6030_pwm_probe(struct platform_device *pdev)
{
	struct twl6030_pwm_chip *twl6030;
	int ret;

	twl6030 = devm_kzalloc(&pdev->dev, sizeof(*twl6030), GFP_KERNEL);
	if (!twl6030)
		return -ENOMEM;

	twl6030->chip.dev = &pdev->dev;
	twl6030->chip.ops = &twl6030_pwm_ops;
	twl6030->chip.base = -1;
	twl6030->chip.npwm = 1;

	ret = pwmchip_add(&twl6030->chip);
	if (ret < 0)
		return ret;

	platform_set_drvdata(pdev, twl6030);

	return 0;
}

static int twl6030_pwm_remove(struct platform_device *pdev)
{
	struct twl6030_pwm_chip *twl6030 = platform_get_drvdata(pdev);

	return pwmchip_remove(&twl6030->chip);
}

static struct platform_driver twl6030_pwm_driver = {
	.driver = {
		.name = "twl6030-pwm",
	},
	.probe = twl6030_pwm_probe,
	.remove = twl6030_pwm_remove,
};
module_platform_driver(twl6030_pwm_driver);

MODULE_ALIAS("platform:twl6030-pwm");
MODULE_LICENSE("GPL");
Commit	Line	Data
31fc03df H	1	/*
	2	* twl6030_pwm.c
	3	* Driver for PHOENIX (TWL6030) Pulse Width Modulator
	4	*
	5	* Copyright (C) 2010 Texas Instruments
	6	* Author: Hemanth V <hemanthv@ti.com>
	7	*
	8	* This program is free software; you can redistribute it and/or modify it
	9	* under the terms of the GNU General Public License version 2 as published by
	10	* the Free Software Foundation.
	11	*
	12	* This program is distributed in the hope that it will be useful, but WITHOUT
	13	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	14	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	15	* more details.
	16	*
	17	* You should have received a copy of the GNU General Public License along with
	18	* this program. If not, see <http://www.gnu.org/licenses/>.
	19	*/
	20
	21	#include <linux/module.h>
	22	#include <linux/platform_device.h>
48a364b7	23	#include <linux/pwm.h>
31fc03df H	24	#include <linux/i2c/twl.h>
	25	#include <linux/slab.h>
	26
	27	#define LED_PWM_CTRL1 0xF4
	28	#define LED_PWM_CTRL2 0xF5
	29
	30	/* Max value for CTRL1 register */
	31	#define PWM_CTRL1_MAX 255
	32
	33	/* Pull down disable */
	34	#define PWM_CTRL2_DIS_PD (1 << 6)
	35
	36	/* Current control 2.5 milli Amps */
	37	#define PWM_CTRL2_CURR_02 (2 << 4)
	38
	39	/* LED supply source */
	40	#define PWM_CTRL2_SRC_VAC (1 << 2)
	41
	42	/* LED modes */
	43	#define PWM_CTRL2_MODE_HW (0 << 0)
	44	#define PWM_CTRL2_MODE_SW (1 << 0)
	45	#define PWM_CTRL2_MODE_DIS (2 << 0)
	46
	47	#define PWM_CTRL2_MODE_MASK 0x3
	48
48a364b7 TR	49	struct twl6030_pwm_chip {
48a364b7 TR	50	struct pwm_chip chip;
31fc03df H	51	};
31fc03df H	52
48a364b7	53	static int twl6030_pwm_request(struct pwm_chip chip, struct pwm_device pwm)
31fc03df	54	{
31fc03df	55	int ret;
48a364b7	56	u8 val;
31fc03df	57
48a364b7 TR	58	/* Configure PWM */
	59	val = PWM_CTRL2_DIS_PD \| PWM_CTRL2_CURR_02 \| PWM_CTRL2_SRC_VAC \|
	60	PWM_CTRL2_MODE_HW;
31fc03df	61
48a364b7 TR	62	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, LED_PWM_CTRL2);
	63	if (ret < 0) {
	64	dev_err(chip->dev, "%s: Failed to configure PWM, Error %d\n",
	65	pwm->label, ret);
	66	return ret;
	67	}
31fc03df	68
48a364b7 TR	69	return 0;
48a364b7 TR	70	}
31fc03df	71
48a364b7 TR	72	static int twl6030_pwm_config(struct pwm_chip chip, struct pwm_device pwm,
	73	int duty_ns, int period_ns)
	74	{
	75	u8 duty_cycle = (duty_ns * PWM_CTRL1_MAX) / period_ns;
	76	int ret;
	77
	78	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, duty_cycle, LED_PWM_CTRL1);
31fc03df H	79	if (ret < 0) {
	80	pr_err("%s: Failed to configure PWM, Error %d\n",
	81	pwm->label, ret);
	82	return ret;
	83	}
48a364b7	84
31fc03df H	85	return 0;
31fc03df H	86	}
31fc03df	87
48a364b7	88	static int twl6030_pwm_enable(struct pwm_chip chip, struct pwm_device pwm)
31fc03df	89	{
31fc03df	90	int ret;
48a364b7	91	u8 val;
31fc03df H	92
	93	ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, LED_PWM_CTRL2);
	94	if (ret < 0) {
48a364b7 TR	95	dev_err(chip->dev, "%s: Failed to enable PWM, Error %d\n",
48a364b7 TR	96	pwm->label, ret);
31fc03df H	97	return ret;
	98	}
	99
	100	/* Change mode to software control */
	101	val &= ~PWM_CTRL2_MODE_MASK;
	102	val \|= PWM_CTRL2_MODE_SW;
	103
	104	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, LED_PWM_CTRL2);
	105	if (ret < 0) {
48a364b7 TR	106	dev_err(chip->dev, "%s: Failed to enable PWM, Error %d\n",
48a364b7 TR	107	pwm->label, ret);
31fc03df H	108	return ret;
	109	}
	110
	111	twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, LED_PWM_CTRL2);
	112	return 0;
	113	}
31fc03df	114
48a364b7	115	static void twl6030_pwm_disable(struct pwm_chip chip, struct pwm_device pwm)
31fc03df	116	{
31fc03df	117	int ret;
48a364b7	118	u8 val;
31fc03df H	119
	120	ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, LED_PWM_CTRL2);
	121	if (ret < 0) {
48a364b7	122	dev_err(chip->dev, "%s: Failed to disable PWM, Error %d\n",
31fc03df H	123	pwm->label, ret);
	124	return;
	125	}
	126
	127	val &= ~PWM_CTRL2_MODE_MASK;
	128	val \|= PWM_CTRL2_MODE_HW;
	129
	130	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, LED_PWM_CTRL2);
	131	if (ret < 0) {
48a364b7	132	dev_err(chip->dev, "%s: Failed to disable PWM, Error %d\n",
31fc03df	133	pwm->label, ret);
31fc03df	134	}
31fc03df	135	}
31fc03df	136
48a364b7 TR	137	static const struct pwm_ops twl6030_pwm_ops = {
	138	.request = twl6030_pwm_request,
	139	.config = twl6030_pwm_config,
	140	.enable = twl6030_pwm_enable,
	141	.disable = twl6030_pwm_disable,
	142	};
	143
	144	static int twl6030_pwm_probe(struct platform_device *pdev)
31fc03df	145	{
48a364b7	146	struct twl6030_pwm_chip *twl6030;
31fc03df	147	int ret;
31fc03df	148
48a364b7 TR	149	twl6030 = devm_kzalloc(&pdev->dev, sizeof(*twl6030), GFP_KERNEL);
	150	if (!twl6030)
	151	return -ENOMEM;
31fc03df	152
48a364b7 TR	153	twl6030->chip.dev = &pdev->dev;
	154	twl6030->chip.ops = &twl6030_pwm_ops;
	155	twl6030->chip.base = -1;
	156	twl6030->chip.npwm = 1;
31fc03df	157
48a364b7 TR	158	ret = pwmchip_add(&twl6030->chip);
	159	if (ret < 0)
	160	return ret;
31fc03df	161
48a364b7	162	platform_set_drvdata(pdev, twl6030);
31fc03df	163
48a364b7	164	return 0;
31fc03df	165	}
31fc03df	166
48a364b7	167	static int twl6030_pwm_remove(struct platform_device *pdev)
31fc03df	168	{
48a364b7 TR	169	struct twl6030_pwm_chip *twl6030 = platform_get_drvdata(pdev);
	170
	171	return pwmchip_remove(&twl6030->chip);
31fc03df	172	}
2b959e7f	173
48a364b7 TR	174	static struct platform_driver twl6030_pwm_driver = {
	175	.driver = {
	176	.name = "twl6030-pwm",
	177	},
	178	.probe = twl6030_pwm_probe,
fd109112	179	.remove = twl6030_pwm_remove,
48a364b7 TR	180	};
	181	module_platform_driver(twl6030_pwm_driver);
	182
	183	MODULE_ALIAS("platform:twl6030-pwm");
2b959e7f	184	MODULE_LICENSE("GPL");