1 /* 2 * pca9532.c - 16-bit Led dimmer 3 * 4 * Copyright (C) 2008 Riku Voipio 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/slab.h> 17 #include <linux/leds.h> 18 #include <linux/input.h> 19 #include <linux/mutex.h> 20 #include <linux/workqueue.h> 21 #include <linux/leds-pca9532.h> 22 23 #define PCA9532_REG_PSC(i) (0x2+(i)*2) 24 #define PCA9532_REG_PWM(i) (0x3+(i)*2) 25 #define PCA9532_REG_LS0 0x6 26 #define LED_REG(led) ((led>>2)+PCA9532_REG_LS0) 27 #define LED_NUM(led) (led & 0x3) 28 29 #define ldev_to_led(c) container_of(c, struct pca9532_led, ldev) 30 31 struct pca9532_data { 32 struct i2c_client *client; 33 struct pca9532_led leds[16]; 34 struct mutex update_lock; 35 struct input_dev *idev; 36 struct work_struct work; 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_calcpwm(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 data->pwm[pwm] = b; 88 data->psc[pwm] = blink; 89 return 0; 90 } 91 92 static int pca9532_setpwm(struct i2c_client *client, int pwm) 93 { 94 struct pca9532_data *data = i2c_get_clientdata(client); 95 mutex_lock(&data->update_lock); 96 i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(pwm), 97 data->pwm[pwm]); 98 i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(pwm), 99 data->psc[pwm]); 100 mutex_unlock(&data->update_lock); 101 return 0; 102 } 103 104 /* Set LED routing */ 105 static void pca9532_setled(struct pca9532_led *led) 106 { 107 struct i2c_client *client = led->client; 108 struct pca9532_data *data = i2c_get_clientdata(client); 109 char reg; 110 111 mutex_lock(&data->update_lock); 112 reg = i2c_smbus_read_byte_data(client, LED_REG(led->id)); 113 /* zero led bits */ 114 reg = reg & ~(0x3<<LED_NUM(led->id)*2); 115 /* set the new value */ 116 reg = reg | (led->state << LED_NUM(led->id)*2); 117 i2c_smbus_write_byte_data(client, LED_REG(led->id), reg); 118 mutex_unlock(&data->update_lock); 119 } 120 121 static void pca9532_set_brightness(struct led_classdev *led_cdev, 122 enum led_brightness value) 123 { 124 int err = 0; 125 struct pca9532_led *led = ldev_to_led(led_cdev); 126 127 if (value == LED_OFF) 128 led->state = PCA9532_OFF; 129 else if (value == LED_FULL) 130 led->state = PCA9532_ON; 131 else { 132 led->state = PCA9532_PWM0; /* Thecus: hardcode one pwm */ 133 err = pca9532_calcpwm(led->client, 0, 0, value); 134 if (err) 135 return; /* XXX: led api doesn't allow error code? */ 136 } 137 schedule_work(&led->work); 138 } 139 140 static int pca9532_set_blink(struct led_classdev *led_cdev, 141 unsigned long *delay_on, unsigned long *delay_off) 142 { 143 struct pca9532_led *led = ldev_to_led(led_cdev); 144 struct i2c_client *client = led->client; 145 int psc; 146 int err = 0; 147 148 if (*delay_on == 0 && *delay_off == 0) { 149 /* led subsystem ask us for a blink rate */ 150 *delay_on = 1000; 151 *delay_off = 1000; 152 } 153 if (*delay_on != *delay_off || *delay_on > 1690 || *delay_on < 6) 154 return -EINVAL; 155 156 /* Thecus specific: only use PSC/PWM 0 */ 157 psc = (*delay_on * 152-1)/1000; 158 err = pca9532_calcpwm(client, 0, psc, led_cdev->brightness); 159 if (err) 160 return err; 161 schedule_work(&led->work); 162 return 0; 163 } 164 165 static int pca9532_event(struct input_dev *dev, unsigned int type, 166 unsigned int code, int value) 167 { 168 struct pca9532_data *data = input_get_drvdata(dev); 169 170 if (!(type == EV_SND && (code == SND_BELL || code == SND_TONE))) 171 return -1; 172 173 /* XXX: allow different kind of beeps with psc/pwm modifications */ 174 if (value > 1 && value < 32767) 175 data->pwm[1] = 127; 176 else 177 data->pwm[1] = 0; 178 179 schedule_work(&data->work); 180 181 return 0; 182 } 183 184 static void pca9532_input_work(struct work_struct *work) 185 { 186 struct pca9532_data *data; 187 data = container_of(work, struct pca9532_data, work); 188 mutex_lock(&data->update_lock); 189 i2c_smbus_write_byte_data(data->client, PCA9532_REG_PWM(1), 190 data->pwm[1]); 191 mutex_unlock(&data->update_lock); 192 } 193 194 static void pca9532_led_work(struct work_struct *work) 195 { 196 struct pca9532_led *led; 197 led = container_of(work, struct pca9532_led, work); 198 if (led->state == PCA9532_PWM0) 199 pca9532_setpwm(led->client, 0); 200 pca9532_setled(led); 201 } 202 203 static void pca9532_destroy_devices(struct pca9532_data *data, int n_devs) 204 { 205 int i = n_devs; 206 207 if (!data) 208 return; 209 210 while (--i >= 0) { 211 switch (data->leds[i].type) { 212 case PCA9532_TYPE_NONE: 213 break; 214 case PCA9532_TYPE_LED: 215 led_classdev_unregister(&data->leds[i].ldev); 216 cancel_work_sync(&data->leds[i].work); 217 break; 218 case PCA9532_TYPE_N2100_BEEP: 219 if (data->idev != NULL) { 220 input_unregister_device(data->idev); 221 cancel_work_sync(&data->work); 222 data->idev = NULL; 223 } 224 break; 225 } 226 } 227 } 228 229 static int pca9532_configure(struct i2c_client *client, 230 struct pca9532_data *data, struct pca9532_platform_data *pdata) 231 { 232 int i, err = 0; 233 234 for (i = 0; i < 2; i++) { 235 data->pwm[i] = pdata->pwm[i]; 236 data->psc[i] = pdata->psc[i]; 237 i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(i), 238 data->pwm[i]); 239 i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(i), 240 data->psc[i]); 241 } 242 243 for (i = 0; i < 16; i++) { 244 struct pca9532_led *led = &data->leds[i]; 245 struct pca9532_led *pled = &pdata->leds[i]; 246 led->client = client; 247 led->id = i; 248 led->type = pled->type; 249 switch (led->type) { 250 case PCA9532_TYPE_NONE: 251 break; 252 case PCA9532_TYPE_LED: 253 led->state = pled->state; 254 led->name = pled->name; 255 led->ldev.name = led->name; 256 led->ldev.brightness = LED_OFF; 257 led->ldev.brightness_set = pca9532_set_brightness; 258 led->ldev.blink_set = pca9532_set_blink; 259 INIT_WORK(&led->work, pca9532_led_work); 260 err = led_classdev_register(&client->dev, &led->ldev); 261 if (err < 0) { 262 dev_err(&client->dev, 263 "couldn't register LED %s\n", 264 led->name); 265 goto exit; 266 } 267 pca9532_setled(led); 268 break; 269 case PCA9532_TYPE_N2100_BEEP: 270 BUG_ON(data->idev); 271 led->state = PCA9532_PWM1; 272 pca9532_setled(led); 273 data->idev = input_allocate_device(); 274 if (data->idev == NULL) { 275 err = -ENOMEM; 276 goto exit; 277 } 278 data->idev->name = pled->name; 279 data->idev->phys = "i2c/pca9532"; 280 data->idev->id.bustype = BUS_HOST; 281 data->idev->id.vendor = 0x001f; 282 data->idev->id.product = 0x0001; 283 data->idev->id.version = 0x0100; 284 data->idev->evbit[0] = BIT_MASK(EV_SND); 285 data->idev->sndbit[0] = BIT_MASK(SND_BELL) | 286 BIT_MASK(SND_TONE); 287 data->idev->event = pca9532_event; 288 input_set_drvdata(data->idev, data); 289 INIT_WORK(&data->work, pca9532_input_work); 290 err = input_register_device(data->idev); 291 if (err) { 292 input_free_device(data->idev); 293 cancel_work_sync(&data->work); 294 data->idev = NULL; 295 goto exit; 296 } 297 break; 298 } 299 } 300 return 0; 301 302 exit: 303 pca9532_destroy_devices(data, i); 304 return err; 305 } 306 307 static int pca9532_probe(struct i2c_client *client, 308 const struct i2c_device_id *id) 309 { 310 struct pca9532_data *data = i2c_get_clientdata(client); 311 struct pca9532_platform_data *pca9532_pdata = client->dev.platform_data; 312 int err; 313 314 if (!pca9532_pdata) 315 return -EIO; 316 317 if (!i2c_check_functionality(client->adapter, 318 I2C_FUNC_SMBUS_BYTE_DATA)) 319 return -EIO; 320 321 data = kzalloc(sizeof(*data), GFP_KERNEL); 322 if (!data) 323 return -ENOMEM; 324 325 dev_info(&client->dev, "setting platform data\n"); 326 i2c_set_clientdata(client, data); 327 data->client = client; 328 mutex_init(&data->update_lock); 329 330 err = pca9532_configure(client, data, pca9532_pdata); 331 if (err) 332 kfree(data); 333 334 return err; 335 } 336 337 static int pca9532_remove(struct i2c_client *client) 338 { 339 struct pca9532_data *data = i2c_get_clientdata(client); 340 pca9532_destroy_devices(data, 16); 341 kfree(data); 342 return 0; 343 } 344 345 static int __init pca9532_init(void) 346 { 347 return i2c_add_driver(&pca9532_driver); 348 } 349 350 static void __exit pca9532_exit(void) 351 { 352 i2c_del_driver(&pca9532_driver); 353 } 354 355 MODULE_AUTHOR("Riku Voipio"); 356 MODULE_LICENSE("GPL"); 357 MODULE_DESCRIPTION("PCA 9532 LED dimmer"); 358 359 module_init(pca9532_init); 360 module_exit(pca9532_exit); 361 362