[linux-block.git] / drivers / leds / leds-pca9685.c

/*
 * Copyright 2013 Maximilian Güntner <maximilian.guentner@gmail.com>
 *
 * This file is subject to the terms and conditions of version 2 of
 * the GNU General Public License.  See the file COPYING in the main
 * directory of this archive for more details.
 *
 * Based on leds-pca963x.c driver by
 * Peter Meerwald <p.meerwald@bct-electronic.com>
 *
 * Driver for the NXP PCA9685 12-Bit PWM LED driver chip.
 *
 */

#include <linux/ctype.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/workqueue.h>

#include <linux/platform_data/leds-pca9685.h>

/* Register Addresses */
#define PCA9685_MODE1 0x00
#define PCA9685_MODE2 0x01
#define PCA9685_LED0_ON_L 0x06
#define PCA9685_ALL_LED_ON_L 0xFA

/* MODE1 Register */
#define PCA9685_ALLCALL 0x00
#define PCA9685_SLEEP   0x04
#define PCA9685_AI      0x05

/* MODE2 Register */
#define PCA9685_INVRT   0x04
#define PCA9685_OUTDRV  0x02

static const struct i2c_device_id pca9685_id[] = {
	{ "pca9685", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, pca9685_id);

struct pca9685_led {
	struct i2c_client *client;
	struct work_struct work;
	u16 brightness;
	struct led_classdev led_cdev;
	int led_num; /* 0-15 */
	char name[32];
};

static void pca9685_write_msg(struct i2c_client *client, u8 *buf, u8 len)
{
	struct i2c_msg msg = {
		.addr = client->addr,
		.flags = 0x00,
		.len = len,
		.buf = buf
	};
	i2c_transfer(client->adapter, &msg, 1);
}

static void pca9685_all_off(struct i2c_client *client)
{
	u8 i2c_buffer[5] = {PCA9685_ALL_LED_ON_L, 0x00, 0x00, 0x00, 0x10};
	pca9685_write_msg(client, i2c_buffer, 5);
}

static void pca9685_led_work(struct work_struct *work)
{
	struct pca9685_led *pca9685;
	u8 i2c_buffer[5];

	pca9685 = container_of(work, struct pca9685_led, work);
	i2c_buffer[0] = PCA9685_LED0_ON_L + 4 * pca9685->led_num;
	/*
	 * 4095 is the maximum brightness, so we set the ON time to 0x1000
	 * which disables the PWM generator for that LED
	 */
	if (pca9685->brightness == 4095)
		*((__le16 *)(i2c_buffer+1)) = cpu_to_le16(0x1000);
	else
		*((__le16 *)(i2c_buffer+1)) = 0x0000;

	if (pca9685->brightness == 0)
		*((__le16 *)(i2c_buffer+3)) = cpu_to_le16(0x1000);
	else if (pca9685->brightness == 4095)
		*((__le16 *)(i2c_buffer+3)) = 0x0000;
	else
		*((__le16 *)(i2c_buffer+3)) = cpu_to_le16(pca9685->brightness);

	pca9685_write_msg(pca9685->client, i2c_buffer, 5);
}

static void pca9685_led_set(struct led_classdev *led_cdev,
		enum led_brightness value)
{
	struct pca9685_led *pca9685;
	pca9685 = container_of(led_cdev, struct pca9685_led, led_cdev);
	pca9685->brightness = value;

	schedule_work(&pca9685->work);
}

static int pca9685_probe(struct i2c_client *client,
		const struct i2c_device_id *id)
{
	struct pca9685_led *pca9685;
	struct pca9685_platform_data *pdata;
	int err;
	u8 i;

	pdata = dev_get_platdata(&client->dev);
	if (pdata) {
		if (pdata->leds.num_leds < 1 || pdata->leds.num_leds > 15) {
			dev_err(&client->dev, "board info must claim 1-16 LEDs");
			return -EINVAL;
		}
	}

	pca9685 = devm_kzalloc(&client->dev, 16 * sizeof(*pca9685), GFP_KERNEL);
	if (!pca9685)
		return -ENOMEM;

	i2c_set_clientdata(client, pca9685);
	pca9685_all_off(client);

	for (i = 0; i < 16; i++) {
		pca9685[i].client = client;
		pca9685[i].led_num = i;
		pca9685[i].name[0] = '\0';
		if (pdata && i < pdata->leds.num_leds) {
			if (pdata->leds.leds[i].name)
				strncpy(pca9685[i].name,
					pdata->leds.leds[i].name,
					sizeof(pca9685[i].name)-1);
			if (pdata->leds.leds[i].default_trigger)
				pca9685[i].led_cdev.default_trigger =
					pdata->leds.leds[i].default_trigger;
		}
		if (strlen(pca9685[i].name) == 0) {
			/*
			 * Write adapter and address to the name as well.
			 * Otherwise multiple chips attached to one host would
			 * not work.
			 */
			snprintf(pca9685[i].name, sizeof(pca9685[i].name),
					"pca9685:%d:x%.2x:%d",
					client->adapter->nr, client->addr, i);
		}
		pca9685[i].led_cdev.name = pca9685[i].name;
		pca9685[i].led_cdev.max_brightness = 0xfff;
		pca9685[i].led_cdev.brightness_set = pca9685_led_set;

		INIT_WORK(&pca9685[i].work, pca9685_led_work);
		err = led_classdev_register(&client->dev, &pca9685[i].led_cdev);
		if (err < 0)
			goto exit;
	}

	if (pdata)
		i2c_smbus_write_byte_data(client, PCA9685_MODE2,
			pdata->outdrv << PCA9685_OUTDRV |
			pdata->inverted << PCA9685_INVRT);
	else
		i2c_smbus_write_byte_data(client, PCA9685_MODE2,
			PCA9685_TOTEM_POLE << PCA9685_OUTDRV);
	/* Enable Auto-Increment, enable oscillator, ALLCALL/SUBADDR disabled */
	i2c_smbus_write_byte_data(client, PCA9685_MODE1, BIT(PCA9685_AI));

	return 0;

exit:
	while (i--) {
		led_classdev_unregister(&pca9685[i].led_cdev);
		cancel_work_sync(&pca9685[i].work);
	}
	return err;
}

static int pca9685_remove(struct i2c_client *client)
{
	struct pca9685_led *pca9685 = i2c_get_clientdata(client);
	u8 i;

	for (i = 0; i < 16; i++) {
		led_classdev_unregister(&pca9685[i].led_cdev);
		cancel_work_sync(&pca9685[i].work);
	}
	pca9685_all_off(client);
	return 0;
}

static struct i2c_driver pca9685_driver = {
	.driver = {
		.name = "leds-pca9685",
		.owner = THIS_MODULE,
	},
	.probe = pca9685_probe,
	.remove = pca9685_remove,
	.id_table = pca9685_id,
};

module_i2c_driver(pca9685_driver);

MODULE_AUTHOR("Maximilian Güntner <maximilian.guentner@gmail.com>");
MODULE_DESCRIPTION("PCA9685 LED Driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
bb6febdc MG	1	/*
	2	* Copyright 2013 Maximilian Güntner <maximilian.guentner@gmail.com>
	3	*
	4	* This file is subject to the terms and conditions of version 2 of
	5	* the GNU General Public License. See the file COPYING in the main
	6	* directory of this archive for more details.
	7	*
	8	* Based on leds-pca963x.c driver by
	9	* Peter Meerwald <p.meerwald@bct-electronic.com>
	10	*
	11	* Driver for the NXP PCA9685 12-Bit PWM LED driver chip.
	12	*
	13	*/
	14
	15	#include <linux/ctype.h>
	16	#include <linux/delay.h>
	17	#include <linux/err.h>
	18	#include <linux/i2c.h>
	19	#include <linux/leds.h>
	20	#include <linux/module.h>
	21	#include <linux/slab.h>
	22	#include <linux/string.h>
	23	#include <linux/workqueue.h>
	24
	25	#include <linux/platform_data/leds-pca9685.h>
	26
	27	/* Register Addresses */
	28	#define PCA9685_MODE1 0x00
	29	#define PCA9685_MODE2 0x01
	30	#define PCA9685_LED0_ON_L 0x06
	31	#define PCA9685_ALL_LED_ON_L 0xFA
	32
	33	/* MODE1 Register */
	34	#define PCA9685_ALLCALL 0x00
	35	#define PCA9685_SLEEP 0x04
	36	#define PCA9685_AI 0x05
	37
	38	/* MODE2 Register */
	39	#define PCA9685_INVRT 0x04
	40	#define PCA9685_OUTDRV 0x02
	41
	42	static const struct i2c_device_id pca9685_id[] = {
	43	{ "pca9685", 0 },
	44	{ }
	45	};
	46	MODULE_DEVICE_TABLE(i2c, pca9685_id);
	47
	48	struct pca9685_led {
	49	struct i2c_client *client;
	50	struct work_struct work;
	51	u16 brightness;
	52	struct led_classdev led_cdev;
	53	int led_num; /* 0-15 */
	54	char name[32];
	55	};
	56
	57	static void pca9685_write_msg(struct i2c_client client, u8 buf, u8 len)
	58	{
	59	struct i2c_msg msg = {
	60	.addr = client->addr,
	61	.flags = 0x00,
	62	.len = len,
	63	.buf = buf
	64	};
65	i2c_transfer(client->adapter, &msg, 1);
66	}
67
68	static void pca9685_all_off(struct i2c_client *client)
69	{
70	u8 i2c_buffer[5] = {PCA9685_ALL_LED_ON_L, 0x00, 0x00, 0x00, 0x10};
71	pca9685_write_msg(client, i2c_buffer, 5);
72	}
73
74	static void pca9685_led_work(struct work_struct *work)
75	{
76	struct pca9685_led *pca9685;
77	u8 i2c_buffer[5];
78
79	pca9685 = container_of(work, struct pca9685_led, work);
80	i2c_buffer[0] = PCA9685_LED0_ON_L + 4 * pca9685->led_num;
81	/*
82	* 4095 is the maximum brightness, so we set the ON time to 0x1000
83	* which disables the PWM generator for that LED
84	*/
85	if (pca9685->brightness == 4095)
86	((__le16 )(i2c_buffer+1)) = cpu_to_le16(0x1000);
87	else
88	((__le16 )(i2c_buffer+1)) = 0x0000;
89
90	if (pca9685->brightness == 0)
91	((__le16 )(i2c_buffer+3)) = cpu_to_le16(0x1000);
92	else if (pca9685->brightness == 4095)
93	((__le16 )(i2c_buffer+3)) = 0x0000;
94	else
95	((__le16 )(i2c_buffer+3)) = cpu_to_le16(pca9685->brightness);
96
97	pca9685_write_msg(pca9685->client, i2c_buffer, 5);
98	}
99
100	static void pca9685_led_set(struct led_classdev *led_cdev,
101	enum led_brightness value)
102	{
103	struct pca9685_led *pca9685;
104	pca9685 = container_of(led_cdev, struct pca9685_led, led_cdev);
105	pca9685->brightness = value;
106
107	schedule_work(&pca9685->work);
108	}
109
110	static int pca9685_probe(struct i2c_client *client,
111	const struct i2c_device_id *id)
112	{
113	struct pca9685_led *pca9685;
114	struct pca9685_platform_data *pdata;
115	int err;
116	u8 i;
117
118	pdata = dev_get_platdata(&client->dev);
119	if (pdata) {
120	if (pdata->leds.num_leds < 1 \|\| pdata->leds.num_leds > 15) {
121	dev_err(&client->dev, "board info must claim 1-16 LEDs");
122	return -EINVAL;
123	}
124	}
125
126	pca9685 = devm_kzalloc(&client->dev, 16 * sizeof(*pca9685), GFP_KERNEL);
127	if (!pca9685)
128	return -ENOMEM;
129
130	i2c_set_clientdata(client, pca9685);
131	pca9685_all_off(client);
132
133	for (i = 0; i < 16; i++) {
134	pca9685[i].client = client;
135	pca9685[i].led_num = i;
136	pca9685[i].name[0] = '\0';
137	if (pdata && i < pdata->leds.num_leds) {
138	if (pdata->leds.leds[i].name)
139	strncpy(pca9685[i].name,
140	pdata->leds.leds[i].name,
141	sizeof(pca9685[i].name)-1);
142	if (pdata->leds.leds[i].default_trigger)
143	pca9685[i].led_cdev.default_trigger =
144	pdata->leds.leds[i].default_trigger;
145	}
146	if (strlen(pca9685[i].name) == 0) {
147	/*
148	* Write adapter and address to the name as well.
149	* Otherwise multiple chips attached to one host would
150	* not work.
151	*/
152	snprintf(pca9685[i].name, sizeof(pca9685[i].name),
153	"pca9685:%d:x%.2x:%d",
154	client->adapter->nr, client->addr, i);
155	}
156	pca9685[i].led_cdev.name = pca9685[i].name;
157	pca9685[i].led_cdev.max_brightness = 0xfff;
158	pca9685[i].led_cdev.brightness_set = pca9685_led_set;
159
160	INIT_WORK(&pca9685[i].work, pca9685_led_work);
161	err = led_classdev_register(&client->dev, &pca9685[i].led_cdev);
162	if (err < 0)
163	goto exit;
164	}
165
166	if (pdata)
167	i2c_smbus_write_byte_data(client, PCA9685_MODE2,
168	pdata->outdrv << PCA9685_OUTDRV \|
169	pdata->inverted << PCA9685_INVRT);
170	else
171	i2c_smbus_write_byte_data(client, PCA9685_MODE2,
172	PCA9685_TOTEM_POLE << PCA9685_OUTDRV);
173	/* Enable Auto-Increment, enable oscillator, ALLCALL/SUBADDR disabled */
174	i2c_smbus_write_byte_data(client, PCA9685_MODE1, BIT(PCA9685_AI));
175
176	return 0;
177
178	exit:
179	while (i--) {
180	led_classdev_unregister(&pca9685[i].led_cdev);
181	cancel_work_sync(&pca9685[i].work);
182	}
183	return err;
184	}
185
186	static int pca9685_remove(struct i2c_client *client)
187	{
188	struct pca9685_led *pca9685 = i2c_get_clientdata(client);
189	u8 i;
190
191	for (i = 0; i < 16; i++) {
192	led_classdev_unregister(&pca9685[i].led_cdev);
193	cancel_work_sync(&pca9685[i].work);
194	}
195	pca9685_all_off(client);
196	return 0;
197	}
198
199	static struct i2c_driver pca9685_driver = {
200	.driver = {
201	.name = "leds-pca9685",
202	.owner = THIS_MODULE,
203	},
204	.probe = pca9685_probe,
205	.remove = pca9685_remove,
206	.id_table = pca9685_id,
207	};
208
209	module_i2c_driver(pca9685_driver);
210
211	MODULE_AUTHOR("Maximilian Güntner <maximilian.guentner@gmail.com>");
212	MODULE_DESCRIPTION("PCA9685 LED Driver");
213	MODULE_LICENSE("GPL v2");