leds-pca9532.c revision e14fa82439d33cef67eaafc1a48960bbfa610c8e 
1/*
2 * pca9532.c - 16-bit Led dimmer
3 *
4 * Copyright (C) 2008 Riku Voipio <riku.voipio@movial.fi>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; version 2 of the License.
9 *
10 * Datasheet: http://www.nxp.com/acrobat/datasheets/PCA9532_3.pdf
11 *
12 */
13
14#include <linux/module.h>
15#include <linux/i2c.h>
16#include <linux/leds.h>
17#include <linux/input.h>
18#include <linux/mutex.h>
19#include <linux/leds-pca9532.h>
20
21static const unsigned short normal_i2c[] = { /*0x60,*/ I2C_CLIENT_END};
22I2C_CLIENT_INSMOD_1(pca9532);
23
24#define PCA9532_REG_PSC(i) (0x2+(i)*2)
25#define PCA9532_REG_PWM(i) (0x3+(i)*2)
26#define PCA9532_REG_LS0  0x6
27#define LED_REG(led) ((led>>2)+PCA9532_REG_LS0)
28#define LED_NUM(led) (led & 0x3)
29
30#define ldev_to_led(c)       container_of(c, struct pca9532_led, ldev)
31
32struct pca9532_data {
33	struct i2c_client *client;
34	struct pca9532_led leds[16];
35	struct mutex update_lock;
36	struct input_dev    *idev;
37	u8 pwm[2];
38	u8 psc[2];
39};
40
41static int pca9532_probe(struct i2c_client *client,
42	const struct i2c_device_id *id);
43static int pca9532_remove(struct i2c_client *client);
44
45static const struct i2c_device_id pca9532_id[] = {
46	{ "pca9532", 0 },
47	{ }
48};
49
50MODULE_DEVICE_TABLE(i2c, pca9532_id);
51
52static struct i2c_driver pca9532_driver = {
53	.driver = {
54		.name   = "pca9532",
55	},
56	.probe  = pca9532_probe,
57	.remove = pca9532_remove,
58	.id_table = pca9532_id,
59};
60
61/* We have two pwm/blinkers, but 16 possible leds to drive. Additionaly,
62 * the clever Thecus people are using one pwm to drive the beeper. So,
63 * as a compromise we average one pwm to the values requested by all
64 * leds that are not ON/OFF.
65 * */
66static int pca9532_setpwm(struct i2c_client *client, int pwm, int blink,
67	enum led_brightness value)
68{
69	int a = 0, b = 0, i = 0;
70	struct pca9532_data *data = i2c_get_clientdata(client);
71	for (i = 0; i < 16; i++) {
72		if (data->leds[i].type == PCA9532_TYPE_LED &&
73			data->leds[i].state == PCA9532_PWM0+pwm) {
74				a++;
75				b += data->leds[i].ldev.brightness;
76		}
77	}
78	if (a == 0) {
79		dev_err(&client->dev,
80		"fear of division by zero %d/%d, wanted %d\n",
81			b, a, value);
82		return -EINVAL;
83	}
84	b = b/a;
85	if (b > 0xFF)
86		return -EINVAL;
87	mutex_lock(&data->update_lock);
88	data->pwm[pwm] = b;
89	i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(pwm),
90		data->pwm[pwm]);
91	data->psc[pwm] = blink;
92	i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(pwm),
93		data->psc[pwm]);
94	mutex_unlock(&data->update_lock);
95	return 0;
96}
97
98/* Set LED routing */
99static void pca9532_setled(struct pca9532_led *led)
100{
101	struct i2c_client *client = led->client;
102	struct pca9532_data *data = i2c_get_clientdata(client);
103	char reg;
104
105	mutex_lock(&data->update_lock);
106	reg = i2c_smbus_read_byte_data(client, LED_REG(led->id));
107	/* zero led bits */
108	reg = reg & ~(0x3<<LED_NUM(led->id)*2);
109	/* set the new value */
110	reg = reg | (led->state << LED_NUM(led->id)*2);
111	i2c_smbus_write_byte_data(client, LED_REG(led->id), reg);
112	mutex_unlock(&data->update_lock);
113}
114
115static void pca9532_set_brightness(struct led_classdev *led_cdev,
116	enum led_brightness value)
117{
118	int err = 0;
119	struct pca9532_led *led = ldev_to_led(led_cdev);
120
121	if (value == LED_OFF)
122		led->state = PCA9532_OFF;
123	else if (value == LED_FULL)
124		led->state = PCA9532_ON;
125	else {
126		led->state = PCA9532_PWM0; /* Thecus: hardcode one pwm */
127		err = pca9532_setpwm(led->client, 0, 0, value);
128		if (err)
129			return; /* XXX: led api doesn't allow error code? */
130	}
131	pca9532_setled(led);
132}
133
134static int pca9532_set_blink(struct led_classdev *led_cdev,
135	unsigned long *delay_on, unsigned long *delay_off)
136{
137	struct pca9532_led *led = ldev_to_led(led_cdev);
138	struct i2c_client *client = led->client;
139	int psc;
140
141	if (*delay_on == 0 && *delay_off == 0) {
142	/* led subsystem ask us for a blink rate */
143		*delay_on  = 1000;
144		*delay_off = 1000;
145	}
146	if (*delay_on != *delay_off || *delay_on > 1690 || *delay_on < 6)
147		return -EINVAL;
148
149	/* Thecus specific: only use PSC/PWM 0 */
150	psc = (*delay_on * 152-1)/1000;
151	return pca9532_setpwm(client, 0, psc, led_cdev->brightness);
152}
153
154int pca9532_event(struct input_dev *dev, unsigned int type, unsigned int code,
155	int value)
156{
157	struct pca9532_data *data = input_get_drvdata(dev);
158
159	if (type != EV_SND && (code != SND_BELL || code != SND_TONE))
160		return -1;
161
162	/* XXX: allow different kind of beeps with psc/pwm modifications */
163	if (value > 1 && value < 32767)
164		data->pwm[1] = 127;
165	else
166		data->pwm[1] = 0;
167
168	dev_info(&dev->dev, "setting beep to %d \n", data->pwm[1]);
169	mutex_lock(&data->update_lock);
170	i2c_smbus_write_byte_data(data->client, PCA9532_REG_PWM(1),
171		data->pwm[1]);
172	mutex_unlock(&data->update_lock);
173
174	return 0;
175}
176
177static int pca9532_configure(struct i2c_client *client,
178	struct pca9532_data *data, struct pca9532_platform_data *pdata)
179{
180	int i, err = 0;
181
182	for (i = 0; i < 2; i++)	{
183		data->pwm[i] = pdata->pwm[i];
184		data->psc[i] = pdata->psc[i];
185		i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(i),
186			data->pwm[i]);
187		i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(i),
188			data->psc[i]);
189	}
190
191	for (i = 0; i < 16; i++) {
192		struct pca9532_led *led = &data->leds[i];
193		struct pca9532_led *pled = &pdata->leds[i];
194		led->client = client;
195		led->id = i;
196		led->type = pled->type;
197		switch (led->type) {
198		case PCA9532_TYPE_NONE:
199			break;
200		case PCA9532_TYPE_LED:
201			led->state = pled->state;
202			led->name =  pled->name;
203			led->ldev.name = led->name;
204			led->ldev.brightness = LED_OFF;
205			led->ldev.brightness_set = pca9532_set_brightness;
206			led->ldev.blink_set = pca9532_set_blink;
207			if (led_classdev_register(&client->dev,
208				&led->ldev) < 0)	{
209				dev_err(&client->dev,
210					"couldn't register LED %s\n",
211					led->name);
212				goto exit;
213			}
214			pca9532_setled(led);
215			break;
216		case PCA9532_TYPE_N2100_BEEP:
217			BUG_ON(data->idev);
218			led->state = PCA9532_PWM1;
219			pca9532_setled(led);
220			data->idev = input_allocate_device();
221			if (data->idev == NULL) {
222				err = -ENOMEM;
223				goto exit;
224			}
225			data->idev->name = pled->name;
226			data->idev->phys = "i2c/pca9532";
227			data->idev->id.bustype = BUS_HOST;
228			data->idev->id.vendor  = 0x001f;
229			data->idev->id.product = 0x0001;
230			data->idev->id.version = 0x0100;
231			data->idev->evbit[0] = BIT_MASK(EV_SND);
232			data->idev->sndbit[0] = BIT_MASK(SND_BELL) |
233						BIT_MASK(SND_TONE);
234			data->idev->event = pca9532_event;
235			input_set_drvdata(data->idev, data);
236			err = input_register_device(data->idev);
237			if (err) {
238				input_free_device(data->idev);
239				data->idev = NULL;
240				goto exit;
241			}
242			break;
243		}
244	}
245	return 0;
246
247exit:
248	if (i > 0)
249		for (i = i - 1; i >= 0; i--)
250			switch (data->leds[i].type) {
251			case PCA9532_TYPE_NONE:
252				break;
253			case PCA9532_TYPE_LED:
254				led_classdev_unregister(&data->leds[i].ldev);
255				break;
256			case PCA9532_TYPE_N2100_BEEP:
257				if (data->idev != NULL) {
258					input_unregister_device(data->idev);
259					input_free_device(data->idev);
260					data->idev = NULL;
261				}
262				break;
263			}
264
265	return err;
266
267}
268
269static int pca9532_probe(struct i2c_client *client,
270	const struct i2c_device_id *id)
271{
272	struct pca9532_data *data = i2c_get_clientdata(client);
273	struct pca9532_platform_data *pca9532_pdata = client->dev.platform_data;
274
275	if (!i2c_check_functionality(client->adapter,
276		I2C_FUNC_SMBUS_BYTE_DATA))
277		return -EIO;
278
279	data = kzalloc(sizeof(struct pca9532_data), GFP_KERNEL);
280	if (!data)
281		return -ENOMEM;
282
283	dev_info(&client->dev, "setting platform data\n");
284	i2c_set_clientdata(client, data);
285	data->client = client;
286	mutex_init(&data->update_lock);
287
288	if (pca9532_pdata == NULL)
289		return -EIO;
290
291	pca9532_configure(client, data, pca9532_pdata);
292	return 0;
293
294}
295
296static int pca9532_remove(struct i2c_client *client)
297{
298	struct pca9532_data *data = i2c_get_clientdata(client);
299	int i;
300	for (i = 0; i < 16; i++)
301		switch (data->leds[i].type) {
302		case PCA9532_TYPE_NONE:
303			break;
304		case PCA9532_TYPE_LED:
305			led_classdev_unregister(&data->leds[i].ldev);
306			break;
307		case PCA9532_TYPE_N2100_BEEP:
308			if (data->idev != NULL) {
309				input_unregister_device(data->idev);
310				input_free_device(data->idev);
311				data->idev = NULL;
312			}
313			break;
314		}
315
316	kfree(data);
317	i2c_set_clientdata(client, NULL);
318	return 0;
319}
320
321static int __init pca9532_init(void)
322{
323	return i2c_add_driver(&pca9532_driver);
324}
325
326static void __exit pca9532_exit(void)
327{
328	i2c_del_driver(&pca9532_driver);
329}
330
331MODULE_AUTHOR("Riku Voipio <riku.voipio@movial.fi>");
332MODULE_LICENSE("GPL");
333MODULE_DESCRIPTION("PCA 9532 LED dimmer");
334
335module_init(pca9532_init);
336module_exit(pca9532_exit);
337
338