xref: /openbmc/linux/drivers/leds/leds-pca9532.c (revision 9ac8d3fb)
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 
21 static const unsigned short normal_i2c[] = { /*0x60,*/ I2C_CLIENT_END};
22 I2C_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 
32 struct 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 
41 static int pca9532_probe(struct i2c_client *client,
42 	const struct i2c_device_id *id);
43 static int pca9532_remove(struct i2c_client *client);
44 
45 static const struct i2c_device_id pca9532_id[] = {
46 	{ "pca9532", 0 },
47 	{ }
48 };
49 
50 MODULE_DEVICE_TABLE(i2c, pca9532_id);
51 
52 static 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  * */
66 static 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 */
99 static 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 
115 static 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 
134 static 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 
154 int 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 
177 static 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 
247 exit:
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 
269 static 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 
296 static 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 
321 static int __init pca9532_init(void)
322 {
323 	return i2c_add_driver(&pca9532_driver);
324 }
325 
326 static void __exit pca9532_exit(void)
327 {
328 	i2c_del_driver(&pca9532_driver);
329 }
330 
331 MODULE_AUTHOR("Riku Voipio <riku.voipio@movial.fi>");
332 MODULE_LICENSE("GPL");
333 MODULE_DESCRIPTION("PCA 9532 LED dimmer");
334 
335 module_init(pca9532_init);
336 module_exit(pca9532_exit);
337 
338