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 static const unsigned short normal_i2c[] = { /*0x60,*/ I2C_CLIENT_END}; 23 I2C_CLIENT_INSMOD_1(pca9532); 24 25 #define PCA9532_REG_PSC(i) (0x2+(i)*2) 26 #define PCA9532_REG_PWM(i) (0x3+(i)*2) 27 #define PCA9532_REG_LS0 0x6 28 #define LED_REG(led) ((led>>2)+PCA9532_REG_LS0) 29 #define LED_NUM(led) (led & 0x3) 30 31 #define ldev_to_led(c) container_of(c, struct pca9532_led, ldev) 32 33 struct pca9532_data { 34 struct i2c_client *client; 35 struct pca9532_led leds[16]; 36 struct mutex update_lock; 37 struct input_dev *idev; 38 struct work_struct work; 39 u8 pwm[2]; 40 u8 psc[2]; 41 }; 42 43 static int pca9532_probe(struct i2c_client *client, 44 const struct i2c_device_id *id); 45 static int pca9532_remove(struct i2c_client *client); 46 47 static const struct i2c_device_id pca9532_id[] = { 48 { "pca9532", 0 }, 49 { } 50 }; 51 52 MODULE_DEVICE_TABLE(i2c, pca9532_id); 53 54 static struct i2c_driver pca9532_driver = { 55 .driver = { 56 .name = "pca9532", 57 }, 58 .probe = pca9532_probe, 59 .remove = pca9532_remove, 60 .id_table = pca9532_id, 61 }; 62 63 /* We have two pwm/blinkers, but 16 possible leds to drive. Additionaly, 64 * the clever Thecus people are using one pwm to drive the beeper. So, 65 * as a compromise we average one pwm to the values requested by all 66 * leds that are not ON/OFF. 67 * */ 68 static int pca9532_calcpwm(struct i2c_client *client, int pwm, int blink, 69 enum led_brightness value) 70 { 71 int a = 0, b = 0, i = 0; 72 struct pca9532_data *data = i2c_get_clientdata(client); 73 for (i = 0; i < 16; i++) { 74 if (data->leds[i].type == PCA9532_TYPE_LED && 75 data->leds[i].state == PCA9532_PWM0+pwm) { 76 a++; 77 b += data->leds[i].ldev.brightness; 78 } 79 } 80 if (a == 0) { 81 dev_err(&client->dev, 82 "fear of division by zero %d/%d, wanted %d\n", 83 b, a, value); 84 return -EINVAL; 85 } 86 b = b/a; 87 if (b > 0xFF) 88 return -EINVAL; 89 data->pwm[pwm] = b; 90 data->psc[pwm] = blink; 91 return 0; 92 } 93 94 static int pca9532_setpwm(struct i2c_client *client, int pwm) 95 { 96 struct pca9532_data *data = i2c_get_clientdata(client); 97 mutex_lock(&data->update_lock); 98 i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(pwm), 99 data->pwm[pwm]); 100 i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(pwm), 101 data->psc[pwm]); 102 mutex_unlock(&data->update_lock); 103 return 0; 104 } 105 106 /* Set LED routing */ 107 static void pca9532_setled(struct pca9532_led *led) 108 { 109 struct i2c_client *client = led->client; 110 struct pca9532_data *data = i2c_get_clientdata(client); 111 char reg; 112 113 mutex_lock(&data->update_lock); 114 reg = i2c_smbus_read_byte_data(client, LED_REG(led->id)); 115 /* zero led bits */ 116 reg = reg & ~(0x3<<LED_NUM(led->id)*2); 117 /* set the new value */ 118 reg = reg | (led->state << LED_NUM(led->id)*2); 119 i2c_smbus_write_byte_data(client, LED_REG(led->id), reg); 120 mutex_unlock(&data->update_lock); 121 } 122 123 static void pca9532_set_brightness(struct led_classdev *led_cdev, 124 enum led_brightness value) 125 { 126 int err = 0; 127 struct pca9532_led *led = ldev_to_led(led_cdev); 128 129 if (value == LED_OFF) 130 led->state = PCA9532_OFF; 131 else if (value == LED_FULL) 132 led->state = PCA9532_ON; 133 else { 134 led->state = PCA9532_PWM0; /* Thecus: hardcode one pwm */ 135 err = pca9532_calcpwm(led->client, 0, 0, value); 136 if (err) 137 return; /* XXX: led api doesn't allow error code? */ 138 } 139 schedule_work(&led->work); 140 } 141 142 static int pca9532_set_blink(struct led_classdev *led_cdev, 143 unsigned long *delay_on, unsigned long *delay_off) 144 { 145 struct pca9532_led *led = ldev_to_led(led_cdev); 146 struct i2c_client *client = led->client; 147 int psc; 148 int err = 0; 149 150 if (*delay_on == 0 && *delay_off == 0) { 151 /* led subsystem ask us for a blink rate */ 152 *delay_on = 1000; 153 *delay_off = 1000; 154 } 155 if (*delay_on != *delay_off || *delay_on > 1690 || *delay_on < 6) 156 return -EINVAL; 157 158 /* Thecus specific: only use PSC/PWM 0 */ 159 psc = (*delay_on * 152-1)/1000; 160 err = pca9532_calcpwm(client, 0, psc, led_cdev->brightness); 161 if (err) 162 return err; 163 schedule_work(&led->work); 164 return 0; 165 } 166 167 static int pca9532_event(struct input_dev *dev, unsigned int type, 168 unsigned int code, int value) 169 { 170 struct pca9532_data *data = input_get_drvdata(dev); 171 172 if (!(type == EV_SND && (code == SND_BELL || code == SND_TONE))) 173 return -1; 174 175 /* XXX: allow different kind of beeps with psc/pwm modifications */ 176 if (value > 1 && value < 32767) 177 data->pwm[1] = 127; 178 else 179 data->pwm[1] = 0; 180 181 schedule_work(&data->work); 182 183 return 0; 184 } 185 186 static void pca9532_input_work(struct work_struct *work) 187 { 188 struct pca9532_data *data; 189 data = container_of(work, struct pca9532_data, work); 190 mutex_lock(&data->update_lock); 191 i2c_smbus_write_byte_data(data->client, PCA9532_REG_PWM(1), 192 data->pwm[1]); 193 mutex_unlock(&data->update_lock); 194 } 195 196 static void pca9532_led_work(struct work_struct *work) 197 { 198 struct pca9532_led *led; 199 led = container_of(work, struct pca9532_led, work); 200 if (led->state == PCA9532_PWM0) 201 pca9532_setpwm(led->client, 0); 202 pca9532_setled(led); 203 } 204 205 static int pca9532_configure(struct i2c_client *client, 206 struct pca9532_data *data, struct pca9532_platform_data *pdata) 207 { 208 int i, err = 0; 209 210 for (i = 0; i < 2; i++) { 211 data->pwm[i] = pdata->pwm[i]; 212 data->psc[i] = pdata->psc[i]; 213 i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(i), 214 data->pwm[i]); 215 i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(i), 216 data->psc[i]); 217 } 218 219 for (i = 0; i < 16; i++) { 220 struct pca9532_led *led = &data->leds[i]; 221 struct pca9532_led *pled = &pdata->leds[i]; 222 led->client = client; 223 led->id = i; 224 led->type = pled->type; 225 switch (led->type) { 226 case PCA9532_TYPE_NONE: 227 break; 228 case PCA9532_TYPE_LED: 229 led->state = pled->state; 230 led->name = pled->name; 231 led->ldev.name = led->name; 232 led->ldev.brightness = LED_OFF; 233 led->ldev.brightness_set = pca9532_set_brightness; 234 led->ldev.blink_set = pca9532_set_blink; 235 INIT_WORK(&led->work, pca9532_led_work); 236 err = led_classdev_register(&client->dev, &led->ldev); 237 if (err < 0) { 238 dev_err(&client->dev, 239 "couldn't register LED %s\n", 240 led->name); 241 goto exit; 242 } 243 pca9532_setled(led); 244 break; 245 case PCA9532_TYPE_N2100_BEEP: 246 BUG_ON(data->idev); 247 led->state = PCA9532_PWM1; 248 pca9532_setled(led); 249 data->idev = input_allocate_device(); 250 if (data->idev == NULL) { 251 err = -ENOMEM; 252 goto exit; 253 } 254 data->idev->name = pled->name; 255 data->idev->phys = "i2c/pca9532"; 256 data->idev->id.bustype = BUS_HOST; 257 data->idev->id.vendor = 0x001f; 258 data->idev->id.product = 0x0001; 259 data->idev->id.version = 0x0100; 260 data->idev->evbit[0] = BIT_MASK(EV_SND); 261 data->idev->sndbit[0] = BIT_MASK(SND_BELL) | 262 BIT_MASK(SND_TONE); 263 data->idev->event = pca9532_event; 264 input_set_drvdata(data->idev, data); 265 INIT_WORK(&data->work, pca9532_input_work); 266 err = input_register_device(data->idev); 267 if (err) { 268 input_free_device(data->idev); 269 cancel_work_sync(&data->work); 270 data->idev = NULL; 271 goto exit; 272 } 273 break; 274 } 275 } 276 return 0; 277 278 exit: 279 if (i > 0) 280 for (i = i - 1; i >= 0; i--) 281 switch (data->leds[i].type) { 282 case PCA9532_TYPE_NONE: 283 break; 284 case PCA9532_TYPE_LED: 285 led_classdev_unregister(&data->leds[i].ldev); 286 cancel_work_sync(&data->leds[i].work); 287 break; 288 case PCA9532_TYPE_N2100_BEEP: 289 if (data->idev != NULL) { 290 input_unregister_device(data->idev); 291 input_free_device(data->idev); 292 cancel_work_sync(&data->work); 293 data->idev = NULL; 294 } 295 break; 296 } 297 298 return err; 299 } 300 301 static int pca9532_probe(struct i2c_client *client, 302 const struct i2c_device_id *id) 303 { 304 struct pca9532_data *data = i2c_get_clientdata(client); 305 struct pca9532_platform_data *pca9532_pdata = client->dev.platform_data; 306 int err; 307 308 if (!pca9532_pdata) 309 return -EIO; 310 311 if (!i2c_check_functionality(client->adapter, 312 I2C_FUNC_SMBUS_BYTE_DATA)) 313 return -EIO; 314 315 data = kzalloc(sizeof(*data), GFP_KERNEL); 316 if (!data) 317 return -ENOMEM; 318 319 dev_info(&client->dev, "setting platform data\n"); 320 i2c_set_clientdata(client, data); 321 data->client = client; 322 mutex_init(&data->update_lock); 323 324 err = pca9532_configure(client, data, pca9532_pdata); 325 if (err) { 326 kfree(data); 327 i2c_set_clientdata(client, NULL); 328 } 329 330 return err; 331 } 332 333 static int pca9532_remove(struct i2c_client *client) 334 { 335 struct pca9532_data *data = i2c_get_clientdata(client); 336 int i; 337 for (i = 0; i < 16; i++) 338 switch (data->leds[i].type) { 339 case PCA9532_TYPE_NONE: 340 break; 341 case PCA9532_TYPE_LED: 342 led_classdev_unregister(&data->leds[i].ldev); 343 cancel_work_sync(&data->leds[i].work); 344 break; 345 case PCA9532_TYPE_N2100_BEEP: 346 if (data->idev != NULL) { 347 input_unregister_device(data->idev); 348 input_free_device(data->idev); 349 cancel_work_sync(&data->work); 350 data->idev = NULL; 351 } 352 break; 353 } 354 355 kfree(data); 356 i2c_set_clientdata(client, NULL); 357 return 0; 358 } 359 360 static int __init pca9532_init(void) 361 { 362 return i2c_add_driver(&pca9532_driver); 363 } 364 365 static void __exit pca9532_exit(void) 366 { 367 i2c_del_driver(&pca9532_driver); 368 } 369 370 MODULE_AUTHOR("Riku Voipio"); 371 MODULE_LICENSE("GPL"); 372 MODULE_DESCRIPTION("PCA 9532 LED dimmer"); 373 374 module_init(pca9532_init); 375 module_exit(pca9532_exit); 376 377