aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/leds/leds-pca9532.c
blob: afac338d50251fbc17b5d9609bc8ea24ac7611d6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
/*
 * pca9532.c - 16-bit Led dimmer
 *
 * Copyright (C) 2008 Riku Voipio
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * Datasheet: http://www.nxp.com/acrobat/datasheets/PCA9532_3.pdf
 *
 */

#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/leds.h>
#include <linux/input.h>
#include <linux/mutex.h>
#include <linux/workqueue.h>
#include <linux/leds-pca9532.h>

#define PCA9532_REG_PSC(i) (0x2+(i)*2)
#define PCA9532_REG_PWM(i) (0x3+(i)*2)
#define PCA9532_REG_LS0  0x6
#define LED_REG(led) ((led>>2)+PCA9532_REG_LS0)
#define LED_NUM(led) (led & 0x3)

#define ldev_to_led(c)       container_of(c, struct pca9532_led, ldev)

struct pca9532_data {
	struct i2c_client *client;
	struct pca9532_led leds[16];
	struct mutex update_lock;
	struct input_dev *idev;
	struct work_struct work;
	u8 pwm[2];
	u8 psc[2];
};

static int pca9532_probe(struct i2c_client *client,
	const struct i2c_device_id *id);
static int pca9532_remove(struct i2c_client *client);

static const struct i2c_device_id pca9532_id[] = {
	{ "pca9532", 0 },
	{ }
};

MODULE_DEVICE_TABLE(i2c, pca9532_id);

static struct i2c_driver pca9532_driver = {
	.driver = {
		.name = "pca9532",
	},
	.probe = pca9532_probe,
	.remove = pca9532_remove,
	.id_table = pca9532_id,
};

/* We have two pwm/blinkers, but 16 possible leds to drive. Additionaly,
 * the clever Thecus people are using one pwm to drive the beeper. So,
 * as a compromise we average one pwm to the values requested by all
 * leds that are not ON/OFF.
 * */
static int pca9532_calcpwm(struct i2c_client *client, int pwm, int blink,
	enum led_brightness value)
{
	int a = 0, b = 0, i = 0;
	struct pca9532_data *data = i2c_get_clientdata(client);
	for (i = 0; i < 16; i++) {
		if (data->leds[i].type == PCA9532_TYPE_LED &&
			data->leds[i].state == PCA9532_PWM0+pwm) {
				a++;
				b += data->leds[i].ldev.brightness;
		}
	}
	if (a == 0) {
		dev_err(&client->dev,
		"fear of division by zero %d/%d, wanted %d\n",
			b, a, value);
		return -EINVAL;
	}
	b = b/a;
	if (b > 0xFF)
		return -EINVAL;
	data->pwm[pwm] = b;
	data->psc[pwm] = blink;
	return 0;
}

static int pca9532_setpwm(struct i2c_client *client, int pwm)
{
	struct pca9532_data *data = i2c_get_clientdata(client);
	mutex_lock(&data->update_lock);
	i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(pwm),
		data->pwm[pwm]);
	i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(pwm),
		data->psc[pwm]);
	mutex_unlock(&data->update_lock);
	return 0;
}

/* Set LED routing */
static void pca9532_setled(struct pca9532_led *led)
{
	struct i2c_client *client = led->client;
	struct pca9532_data *data = i2c_get_clientdata(client);
	char reg;

	mutex_lock(&data->update_lock);
	reg = i2c_smbus_read_byte_data(client, LED_REG(led->id));
	/* zero led bits */
	reg = reg & ~(0x3<<LED_NUM(led->id)*2);
	/* set the new value */
	reg = reg | (led->state << LED_NUM(led->id)*2);
	i2c_smbus_write_byte_data(client, LED_REG(led->id), reg);
	mutex_unlock(&data->update_lock);
}

static void pca9532_set_brightness(struct led_classdev *led_cdev,
	enum led_brightness value)
{
	int err = 0;
	struct pca9532_led *led = ldev_to_led(led_cdev);

	if (value == LED_OFF)
		led->state = PCA9532_OFF;
	else if (value == LED_FULL)
		led->state = PCA9532_ON;
	else {
		led->state = PCA9532_PWM0; /* Thecus: hardcode one pwm */
		err = pca9532_calcpwm(led->client, 0, 0, value);
		if (err)
			return; /* XXX: led api doesn't allow error code? */
	}
	schedule_work(&led->work);
}

static int pca9532_set_blink(struct led_classdev *led_cdev,
	unsigned long *delay_on, unsigned long *delay_off)
{
	struct pca9532_led *led = ldev_to_led(led_cdev);
	struct i2c_client *client = led->client;
	int psc;
	int err = 0;

	if (*delay_on == 0 && *delay_off == 0) {
	/* led subsystem ask us for a blink rate */
		*delay_on = 1000;
		*delay_off = 1000;
	}
	if (*delay_on != *delay_off || *delay_on > 1690 || *delay_on < 6)
		return -EINVAL;

	/* Thecus specific: only use PSC/PWM 0 */
	psc = (*delay_on * 152-1)/1000;
	err = pca9532_calcpwm(client, 0, psc, led_cdev->brightness);
	if (err)
		return err;
	schedule_work(&led->work);
	return 0;
}

static int pca9532_event(struct input_dev *dev, unsigned int type,
	unsigned int code, int value)
{
	struct pca9532_data *data = input_get_drvdata(dev);

	if (!(type == EV_SND && (code == SND_BELL || code == SND_TONE)))
		return -1;

	/* XXX: allow different kind of beeps with psc/pwm modifications */
	if (value > 1 && value < 32767)
		data->pwm[1] = 127;
	else
		data->pwm[1] = 0;

	schedule_work(&data->work);

	return 0;
}

static void pca9532_input_work(struct work_struct *work)
{
	struct pca9532_data *data;
	data = container_of(work, struct pca9532_data, work);
	mutex_lock(&data->update_lock);
	i2c_smbus_write_byte_data(data->client, PCA9532_REG_PWM(1),
		data->pwm[1]);
	mutex_unlock(&data->update_lock);
}

static void pca9532_led_work(struct work_struct *work)
{
	struct pca9532_led *led;
	led = container_of(work, struct pca9532_led, work);
	if (led->state == PCA9532_PWM0)
		pca9532_setpwm(led->client, 0);
	pca9532_setled(led);
}

static void pca9532_destroy_devices(struct pca9532_data *data, int n_devs)
{
	int i = n_devs;

	if (!data)
		return;

	while (--i >= 0) {
		switch (data->leds[i].type) {
		case PCA9532_TYPE_NONE:
			break;
		case PCA9532_TYPE_LED:
			led_classdev_unregister(&data->leds[i].ldev);
			cancel_work_sync(&data->leds[i].work);
			break;
		case PCA9532_TYPE_N2100_BEEP:
			if (data->idev != NULL) {
				input_unregister_device(data->idev);
				cancel_work_sync(&data->work);
				data->idev = NULL;
			}
			break;
		}
	}
}

static int pca9532_configure(struct i2c_client *client,
	struct pca9532_data *data, struct pca9532_platform_data *pdata)
{
	int i, err = 0;

	for (i = 0; i < 2; i++)	{
		data->pwm[i] = pdata->pwm[i];
		data->psc[i] = pdata->psc[i];
		i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(i),
			data->pwm[i]);
		i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(i),
			data->psc[i]);
	}

	for (i = 0; i < 16; i++) {
		struct pca9532_led *led = &data->leds[i];
		struct pca9532_led *pled = &pdata->leds[i];
		led->client = client;
		led->id = i;
		led->type = pled->type;
		switch (led->type) {
		case PCA9532_TYPE_NONE:
			break;
		case PCA9532_TYPE_LED:
			led->state = pled->state;
			led->name = pled->name;
			led->ldev.name = led->name;
			led->ldev.brightness = LED_OFF;
			led->ldev.brightness_set = pca9532_set_brightness;
			led->ldev.blink_set = pca9532_set_blink;
			INIT_WORK(&led->work, pca9532_led_work);
			err = led_classdev_register(&client->dev, &led->ldev);
			if (err < 0) {
				dev_err(&client->dev,
					"couldn't register LED %s\n",
					led->name);
				goto exit;
			}
			pca9532_setled(led);
			break;
		case PCA9532_TYPE_N2100_BEEP:
			BUG_ON(data->idev);
			led->state = PCA9532_PWM1;
			pca9532_setled(led);
			data->idev = input_allocate_device();
			if (data->idev == NULL) {
				err = -ENOMEM;
				goto exit;
			}
			data->idev->name = pled->name;
			data->idev->phys = "i2c/pca9532";
			data->idev->id.bustype = BUS_HOST;
			data->idev->id.vendor = 0x001f;
			data->idev->id.product = 0x0001;
			data->idev->id.version = 0x0100;
			data->idev->evbit[0] = BIT_MASK(EV_SND);
			data->idev->sndbit[0] = BIT_MASK(SND_BELL) |
						BIT_MASK(SND_TONE);
			data->idev->event = pca9532_event;
			input_set_drvdata(data->idev, data);
			INIT_WORK(&data->work, pca9532_input_work);
			err = input_register_device(data->idev);
			if (err) {
				input_free_device(data->idev);
				cancel_work_sync(&data->work);
				data->idev = NULL;
				goto exit;
			}
			break;
		}
	}
	return 0;

exit:
	pca9532_destroy_devices(data, i);
	return err;
}

static int pca9532_probe(struct i2c_client *client,
	const struct i2c_device_id *id)
{
	struct pca9532_data *data = i2c_get_clientdata(client);
	struct pca9532_platform_data *pca9532_pdata = client->dev.platform_data;
	int err;

	if (!pca9532_pdata)
		return -EIO;

	if (!i2c_check_functionality(client->adapter,
		I2C_FUNC_SMBUS_BYTE_DATA))
		return -EIO;

	data = kzalloc(sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	dev_info(&client->dev, "setting platform data\n");
	i2c_set_clientdata(client, data);
	data->client = client;
	mutex_init(&data->update_lock);

	err = pca9532_configure(client, data, pca9532_pdata);
	if (err)
		kfree(data);

	return err;
}

static int pca9532_remove(struct i2c_client *client)
{
	struct pca9532_data *data = i2c_get_clientdata(client);
	pca9532_destroy_devices(data, 16);
	kfree(data);
	return 0;
}

static int __init pca9532_init(void)
{
	return i2c_add_driver(&pca9532_driver);
}

static void __exit pca9532_exit(void)
{
	i2c_del_driver(&pca9532_driver);
}

MODULE_AUTHOR("Riku Voipio");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("PCA 9532 LED dimmer");

module_init(pca9532_init);
module_exit(pca9532_exit);