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 int pca9532_configure(struct i2c_client *client, 204 struct pca9532_data *data, struct pca9532_platform_data *pdata) 205 { 206 int i, err = 0; 207 208 for (i = 0; i < 2; i++) { 209 data->pwm[i] = pdata->pwm[i]; 210 data->psc[i] = pdata->psc[i]; 211 i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(i), 212 data->pwm[i]); 213 i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(i), 214 data->psc[i]); 215 } 216 217 for (i = 0; i < 16; i++) { 218 struct pca9532_led *led = &data->leds[i]; 219 struct pca9532_led *pled = &pdata->leds[i]; 220 led->client = client; 221 led->id = i; 222 led->type = pled->type; 223 switch (led->type) { 224 case PCA9532_TYPE_NONE: 225 break; 226 case PCA9532_TYPE_LED: 227 led->state = pled->state; 228 led->name = pled->name; 229 led->ldev.name = led->name; 230 led->ldev.brightness = LED_OFF; 231 led->ldev.brightness_set = pca9532_set_brightness; 232 led->ldev.blink_set = pca9532_set_blink; 233 INIT_WORK(&led->work, pca9532_led_work); 234 err = led_classdev_register(&client->dev, &led->ldev); 235 if (err < 0) { 236 dev_err(&client->dev, 237 "couldn't register LED %s\n", 238 led->name); 239 goto exit; 240 } 241 pca9532_setled(led); 242 break; 243 case PCA9532_TYPE_N2100_BEEP: 244 BUG_ON(data->idev); 245 led->state = PCA9532_PWM1; 246 pca9532_setled(led); 247 data->idev = input_allocate_device(); 248 if (data->idev == NULL) { 249 err = -ENOMEM; 250 goto exit; 251 } 252 data->idev->name = pled->name; 253 data->idev->phys = "i2c/pca9532"; 254 data->idev->id.bustype = BUS_HOST; 255 data->idev->id.vendor = 0x001f; 256 data->idev->id.product = 0x0001; 257 data->idev->id.version = 0x0100; 258 data->idev->evbit[0] = BIT_MASK(EV_SND); 259 data->idev->sndbit[0] = BIT_MASK(SND_BELL) | 260 BIT_MASK(SND_TONE); 261 data->idev->event = pca9532_event; 262 input_set_drvdata(data->idev, data); 263 INIT_WORK(&data->work, pca9532_input_work); 264 err = input_register_device(data->idev); 265 if (err) { 266 input_free_device(data->idev); 267 cancel_work_sync(&data->work); 268 data->idev = NULL; 269 goto exit; 270 } 271 break; 272 } 273 } 274 return 0; 275 276 exit: 277 if (i > 0) 278 for (i = i - 1; i >= 0; i--) 279 switch (data->leds[i].type) { 280 case PCA9532_TYPE_NONE: 281 break; 282 case PCA9532_TYPE_LED: 283 led_classdev_unregister(&data->leds[i].ldev); 284 cancel_work_sync(&data->leds[i].work); 285 break; 286 case PCA9532_TYPE_N2100_BEEP: 287 if (data->idev != NULL) { 288 input_unregister_device(data->idev); 289 input_free_device(data->idev); 290 cancel_work_sync(&data->work); 291 data->idev = NULL; 292 } 293 break; 294 } 295 296 return err; 297 } 298 299 static int pca9532_probe(struct i2c_client *client, 300 const struct i2c_device_id *id) 301 { 302 struct pca9532_data *data = i2c_get_clientdata(client); 303 struct pca9532_platform_data *pca9532_pdata = client->dev.platform_data; 304 int err; 305 306 if (!pca9532_pdata) 307 return -EIO; 308 309 if (!i2c_check_functionality(client->adapter, 310 I2C_FUNC_SMBUS_BYTE_DATA)) 311 return -EIO; 312 313 data = kzalloc(sizeof(*data), GFP_KERNEL); 314 if (!data) 315 return -ENOMEM; 316 317 dev_info(&client->dev, "setting platform data\n"); 318 i2c_set_clientdata(client, data); 319 data->client = client; 320 mutex_init(&data->update_lock); 321 322 err = pca9532_configure(client, data, pca9532_pdata); 323 if (err) 324 kfree(data); 325 326 return err; 327 } 328 329 static int pca9532_remove(struct i2c_client *client) 330 { 331 struct pca9532_data *data = i2c_get_clientdata(client); 332 int i; 333 for (i = 0; i < 16; i++) 334 switch (data->leds[i].type) { 335 case PCA9532_TYPE_NONE: 336 break; 337 case PCA9532_TYPE_LED: 338 led_classdev_unregister(&data->leds[i].ldev); 339 cancel_work_sync(&data->leds[i].work); 340 break; 341 case PCA9532_TYPE_N2100_BEEP: 342 if (data->idev != NULL) { 343 input_unregister_device(data->idev); 344 input_free_device(data->idev); 345 cancel_work_sync(&data->work); 346 data->idev = NULL; 347 } 348 break; 349 } 350 351 kfree(data); 352 return 0; 353 } 354 355 static int __init pca9532_init(void) 356 { 357 return i2c_add_driver(&pca9532_driver); 358 } 359 360 static void __exit pca9532_exit(void) 361 { 362 i2c_del_driver(&pca9532_driver); 363 } 364 365 MODULE_AUTHOR("Riku Voipio"); 366 MODULE_LICENSE("GPL"); 367 MODULE_DESCRIPTION("PCA 9532 LED dimmer"); 368 369 module_init(pca9532_init); 370 module_exit(pca9532_exit); 371 372