linux/drivers/leds/leds-pca9532.c
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   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