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/leds.h> 17 #include <linux/input.h> 18 #include <linux/mutex.h> 19 #include <linux/workqueue.h> 20 #include <linux/leds-pca9532.h> 21 22 #define PCA9532_REG_PSC(i) (0x2+(i)*2) 23 #define PCA9532_REG_PWM(i) (0x3+(i)*2) 24 #define PCA9532_REG_LS0 0x6 25 #define LED_REG(led) ((led>>2)+PCA9532_REG_LS0) 26 #define LED_NUM(led) (led & 0x3) 27 28 #define ldev_to_led(c) container_of(c, struct pca9532_led, ldev) 29 30 struct pca9532_data { 31 struct i2c_client *client; 32 struct pca9532_led leds[16]; 33 struct mutex update_lock; 34 struct input_dev *idev; 35 struct work_struct work; 36 u8 pwm[2]; 37 u8 psc[2]; 38 }; 39 40 static int pca9532_probe(struct i2c_client *client, 41 const struct i2c_device_id *id); 42 static int pca9532_remove(struct i2c_client *client); 43 44 static const struct i2c_device_id pca9532_id[] = { 45 { "pca9532", 0 }, 46 { } 47 }; 48 49 MODULE_DEVICE_TABLE(i2c, pca9532_id); 50 51 static struct i2c_driver pca9532_driver = { 52 .driver = { 53 .name = "pca9532", 54 }, 55 .probe = pca9532_probe, 56 .remove = pca9532_remove, 57 .id_table = pca9532_id, 58 }; 59 60 /* We have two pwm/blinkers, but 16 possible leds to drive. Additionaly, 61 * the clever Thecus people are using one pwm to drive the beeper. So, 62 * as a compromise we average one pwm to the values requested by all 63 * leds that are not ON/OFF. 64 * */ 65 static int pca9532_calcpwm(struct i2c_client *client, int pwm, int blink, 66 enum led_brightness value) 67 { 68 int a = 0, b = 0, i = 0; 69 struct pca9532_data *data = i2c_get_clientdata(client); 70 for (i = 0; i < 16; i++) { 71 if (data->leds[i].type == PCA9532_TYPE_LED && 72 data->leds[i].state == PCA9532_PWM0+pwm) { 73 a++; 74 b += data->leds[i].ldev.brightness; 75 } 76 } 77 if (a == 0) { 78 dev_err(&client->dev, 79 "fear of division by zero %d/%d, wanted %d\n", 80 b, a, value); 81 return -EINVAL; 82 } 83 b = b/a; 84 if (b > 0xFF) 85 return -EINVAL; 86 data->pwm[pwm] = b; 87 data->psc[pwm] = blink; 88 return 0; 89 } 90 91 static int pca9532_setpwm(struct i2c_client *client, int pwm) 92 { 93 struct pca9532_data *data = i2c_get_clientdata(client); 94 mutex_lock(&data->update_lock); 95 i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(pwm), 96 data->pwm[pwm]); 97 i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(pwm), 98 data->psc[pwm]); 99 mutex_unlock(&data->update_lock); 100 return 0; 101 } 102 103 /* Set LED routing */ 104 static void pca9532_setled(struct pca9532_led *led) 105 { 106 struct i2c_client *client = led->client; 107 struct pca9532_data *data = i2c_get_clientdata(client); 108 char reg; 109 110 mutex_lock(&data->update_lock); 111 reg = i2c_smbus_read_byte_data(client, LED_REG(led->id)); 112 /* zero led bits */ 113 reg = reg & ~(0x3<<LED_NUM(led->id)*2); 114 /* set the new value */ 115 reg = reg | (led->state << LED_NUM(led->id)*2); 116 i2c_smbus_write_byte_data(client, LED_REG(led->id), reg); 117 mutex_unlock(&data->update_lock); 118 } 119 120 static void pca9532_set_brightness(struct led_classdev *led_cdev, 121 enum led_brightness value) 122 { 123 int err = 0; 124 struct pca9532_led *led = ldev_to_led(led_cdev); 125 126 if (value == LED_OFF) 127 led->state = PCA9532_OFF; 128 else if (value == LED_FULL) 129 led->state = PCA9532_ON; 130 else { 131 led->state = PCA9532_PWM0; /* Thecus: hardcode one pwm */ 132 err = pca9532_calcpwm(led->client, 0, 0, value); 133 if (err) 134 return; /* XXX: led api doesn't allow error code? */ 135 } 136 schedule_work(&led->work); 137 } 138 139 static int pca9532_set_blink(struct led_classdev *led_cdev, 140 unsigned long *delay_on, unsigned long *delay_off) 141 { 142 struct pca9532_led *led = ldev_to_led(led_cdev); 143 struct i2c_client *client = led->client; 144 int psc; 145 int err = 0; 146 147 if (*delay_on == 0 && *delay_off == 0) { 148 /* led subsystem ask us for a blink rate */ 149 *delay_on = 1000; 150 *delay_off = 1000; 151 } 152 if (*delay_on != *delay_off || *delay_on > 1690 || *delay_on < 6) 153 return -EINVAL; 154 155 /* Thecus specific: only use PSC/PWM 0 */ 156 psc = (*delay_on * 152-1)/1000; 157 err = pca9532_calcpwm(client, 0, psc, led_cdev->brightness); 158 if (err) 159 return err; 160 schedule_work(&led->work); 161 return 0; 162 } 163 164 static int pca9532_event(struct input_dev *dev, unsigned int type, 165 unsigned int code, int value) 166 { 167 struct pca9532_data *data = input_get_drvdata(dev); 168 169 if (!(type == EV_SND && (code == SND_BELL || code == SND_TONE))) 170 return -1; 171 172 /* XXX: allow different kind of beeps with psc/pwm modifications */ 173 if (value > 1 && value < 32767) 174 data->pwm[1] = 127; 175 else 176 data->pwm[1] = 0; 177 178 schedule_work(&data->work); 179 180 return 0; 181 } 182 183 static void pca9532_input_work(struct work_struct *work) 184 { 185 struct pca9532_data *data; 186 data = container_of(work, struct pca9532_data, work); 187 mutex_lock(&data->update_lock); 188 i2c_smbus_write_byte_data(data->client, PCA9532_REG_PWM(1), 189 data->pwm[1]); 190 mutex_unlock(&data->update_lock); 191 } 192 193 static void pca9532_led_work(struct work_struct *work) 194 { 195 struct pca9532_led *led; 196 led = container_of(work, struct pca9532_led, work); 197 if (led->state == PCA9532_PWM0) 198 pca9532_setpwm(led->client, 0); 199 pca9532_setled(led); 200 } 201 202 static int pca9532_configure(struct i2c_client *client, 203 struct pca9532_data *data, struct pca9532_platform_data *pdata) 204 { 205 int i, err = 0; 206 207 for (i = 0; i < 2; i++) { 208 data->pwm[i] = pdata->pwm[i]; 209 data->psc[i] = pdata->psc[i]; 210 i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(i), 211 data->pwm[i]); 212 i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(i), 213 data->psc[i]); 214 } 215 216 for (i = 0; i < 16; i++) { 217 struct pca9532_led *led = &data->leds[i]; 218 struct pca9532_led *pled = &pdata->leds[i]; 219 led->client = client; 220 led->id = i; 221 led->type = pled->type; 222 switch (led->type) { 223 case PCA9532_TYPE_NONE: 224 break; 225 case PCA9532_TYPE_LED: 226 led->state = pled->state; 227 led->name = pled->name; 228 led->ldev.name = led->name; 229 led->ldev.brightness = LED_OFF; 230 led->ldev.brightness_set = pca9532_set_brightness; 231 led->ldev.blink_set = pca9532_set_blink; 232 INIT_WORK(&led->work, pca9532_led_work); 233 err = led_classdev_register(&client->dev, &led->ldev); 234 if (err < 0) { 235 dev_err(&client->dev, 236 "couldn't register LED %s\n", 237 led->name); 238 goto exit; 239 } 240 pca9532_setled(led); 241 break; 242 case PCA9532_TYPE_N2100_BEEP: 243 BUG_ON(data->idev); 244 led->state = PCA9532_PWM1; 245 pca9532_setled(led); 246 data->idev = input_allocate_device(); 247 if (data->idev == NULL) { 248 err = -ENOMEM; 249 goto exit; 250 } 251 data->idev->name = pled->name; 252 data->idev->phys = "i2c/pca9532"; 253 data->idev->id.bustype = BUS_HOST; 254 data->idev->id.vendor = 0x001f; 255 data->idev->id.product = 0x0001; 256 data->idev->id.version = 0x0100; 257 data->idev->evbit[0] = BIT_MASK(EV_SND); 258 data->idev->sndbit[0] = BIT_MASK(SND_BELL) | 259 BIT_MASK(SND_TONE); 260 data->idev->event = pca9532_event; 261 input_set_drvdata(data->idev, data); 262 INIT_WORK(&data->work, pca9532_input_work); 263 err = input_register_device(data->idev); 264 if (err) { 265 input_free_device(data->idev); 266 cancel_work_sync(&data->work); 267 data->idev = NULL; 268 goto exit; 269 } 270 break; 271 } 272 } 273 return 0; 274 275 exit: 276 if (i > 0) 277 for (i = i - 1; i >= 0; i--) 278 switch (data->leds[i].type) { 279 case PCA9532_TYPE_NONE: 280 break; 281 case PCA9532_TYPE_LED: 282 led_classdev_unregister(&data->leds[i].ldev); 283 cancel_work_sync(&data->leds[i].work); 284 break; 285 case PCA9532_TYPE_N2100_BEEP: 286 if (data->idev != NULL) { 287 input_unregister_device(data->idev); 288 input_free_device(data->idev); 289 cancel_work_sync(&data->work); 290 data->idev = NULL; 291 } 292 break; 293 } 294 295 return err; 296 } 297 298 static int pca9532_probe(struct i2c_client *client, 299 const struct i2c_device_id *id) 300 { 301 struct pca9532_data *data = i2c_get_clientdata(client); 302 struct pca9532_platform_data *pca9532_pdata = client->dev.platform_data; 303 int err; 304 305 if (!pca9532_pdata) 306 return -EIO; 307 308 if (!i2c_check_functionality(client->adapter, 309 I2C_FUNC_SMBUS_BYTE_DATA)) 310 return -EIO; 311 312 data = kzalloc(sizeof(*data), GFP_KERNEL); 313 if (!data) 314 return -ENOMEM; 315 316 dev_info(&client->dev, "setting platform data\n"); 317 i2c_set_clientdata(client, data); 318 data->client = client; 319 mutex_init(&data->update_lock); 320 321 err = pca9532_configure(client, data, pca9532_pdata); 322 if (err) { 323 kfree(data); 324 i2c_set_clientdata(client, NULL); 325 } 326 327 return err; 328 } 329 330 static int pca9532_remove(struct i2c_client *client) 331 { 332 struct pca9532_data *data = i2c_get_clientdata(client); 333 int i; 334 for (i = 0; i < 16; i++) 335 switch (data->leds[i].type) { 336 case PCA9532_TYPE_NONE: 337 break; 338 case PCA9532_TYPE_LED: 339 led_classdev_unregister(&data->leds[i].ldev); 340 cancel_work_sync(&data->leds[i].work); 341 break; 342 case PCA9532_TYPE_N2100_BEEP: 343 if (data->idev != NULL) { 344 input_unregister_device(data->idev); 345 input_free_device(data->idev); 346 cancel_work_sync(&data->work); 347 data->idev = NULL; 348 } 349 break; 350 } 351 352 kfree(data); 353 i2c_set_clientdata(client, NULL); 354 return 0; 355 } 356 357 static int __init pca9532_init(void) 358 { 359 return i2c_add_driver(&pca9532_driver); 360 } 361 362 static void __exit pca9532_exit(void) 363 { 364 i2c_del_driver(&pca9532_driver); 365 } 366 367 MODULE_AUTHOR("Riku Voipio"); 368 MODULE_LICENSE("GPL"); 369 MODULE_DESCRIPTION("PCA 9532 LED dimmer"); 370 371 module_init(pca9532_init); 372 module_exit(pca9532_exit); 373 374