drivers/leds/leds-pca9532.c

   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