1 /* 2 * wm8994-core.c -- Device access for Wolfson WM8994 3 * 4 * Copyright 2009 Wolfson Microelectronics PLC. 5 * 6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> 7 * 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms of the GNU General Public License as published by the 10 * Free Software Foundation; either version 2 of the License, or (at your 11 * option) any later version. 12 * 13 */ 14 15 #include <linux/kernel.h> 16 #include <linux/module.h> 17 #include <linux/slab.h> 18 #include <linux/i2c.h> 19 #include <linux/err.h> 20 #include <linux/delay.h> 21 #include <linux/mfd/core.h> 22 #include <linux/of.h> 23 #include <linux/of_device.h> 24 #include <linux/of_gpio.h> 25 #include <linux/pm_runtime.h> 26 #include <linux/regmap.h> 27 #include <linux/regulator/consumer.h> 28 #include <linux/regulator/machine.h> 29 30 #include <linux/mfd/wm8994/core.h> 31 #include <linux/mfd/wm8994/pdata.h> 32 #include <linux/mfd/wm8994/registers.h> 33 34 #include "wm8994.h" 35 36 static const struct mfd_cell wm8994_regulator_devs[] = { 37 { 38 .name = "wm8994-ldo", 39 .id = 0, 40 .pm_runtime_no_callbacks = true, 41 }, 42 { 43 .name = "wm8994-ldo", 44 .id = 1, 45 .pm_runtime_no_callbacks = true, 46 }, 47 }; 48 49 static struct resource wm8994_codec_resources[] = { 50 { 51 .start = WM8994_IRQ_TEMP_SHUT, 52 .end = WM8994_IRQ_TEMP_WARN, 53 .flags = IORESOURCE_IRQ, 54 }, 55 }; 56 57 static struct resource wm8994_gpio_resources[] = { 58 { 59 .start = WM8994_IRQ_GPIO(1), 60 .end = WM8994_IRQ_GPIO(11), 61 .flags = IORESOURCE_IRQ, 62 }, 63 }; 64 65 static const struct mfd_cell wm8994_devs[] = { 66 { 67 .name = "wm8994-codec", 68 .num_resources = ARRAY_SIZE(wm8994_codec_resources), 69 .resources = wm8994_codec_resources, 70 }, 71 72 { 73 .name = "wm8994-gpio", 74 .num_resources = ARRAY_SIZE(wm8994_gpio_resources), 75 .resources = wm8994_gpio_resources, 76 .pm_runtime_no_callbacks = true, 77 }, 78 }; 79 80 /* 81 * Supplies for the main bulk of CODEC; the LDO supplies are ignored 82 * and should be handled via the standard regulator API supply 83 * management. 84 */ 85 static const char *wm1811_main_supplies[] = { 86 "DBVDD1", 87 "DBVDD2", 88 "DBVDD3", 89 "DCVDD", 90 "AVDD1", 91 "AVDD2", 92 "CPVDD", 93 "SPKVDD1", 94 "SPKVDD2", 95 }; 96 97 static const char *wm8994_main_supplies[] = { 98 "DBVDD", 99 "DCVDD", 100 "AVDD1", 101 "AVDD2", 102 "CPVDD", 103 "SPKVDD1", 104 "SPKVDD2", 105 }; 106 107 static const char *wm8958_main_supplies[] = { 108 "DBVDD1", 109 "DBVDD2", 110 "DBVDD3", 111 "DCVDD", 112 "AVDD1", 113 "AVDD2", 114 "CPVDD", 115 "SPKVDD1", 116 "SPKVDD2", 117 }; 118 119 #ifdef CONFIG_PM 120 static int wm8994_suspend(struct device *dev) 121 { 122 struct wm8994 *wm8994 = dev_get_drvdata(dev); 123 int ret; 124 125 /* Don't actually go through with the suspend if the CODEC is 126 * still active for accessory detect. */ 127 switch (wm8994->type) { 128 case WM8958: 129 case WM1811: 130 ret = wm8994_reg_read(wm8994, WM8958_MIC_DETECT_1); 131 if (ret < 0) { 132 dev_err(dev, "Failed to read power status: %d\n", ret); 133 } else if (ret & WM8958_MICD_ENA) { 134 dev_dbg(dev, "CODEC still active, ignoring suspend\n"); 135 return 0; 136 } 137 break; 138 default: 139 break; 140 } 141 142 /* Disable LDO pulldowns while the device is suspended if we 143 * don't know that something will be driving them. */ 144 if (!wm8994->ldo_ena_always_driven) 145 wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2, 146 WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD, 147 WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD); 148 149 /* Explicitly put the device into reset in case regulators 150 * don't get disabled in order to ensure consistent restart. 151 */ 152 wm8994_reg_write(wm8994, WM8994_SOFTWARE_RESET, 153 wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET)); 154 155 regcache_mark_dirty(wm8994->regmap); 156 157 /* Restore GPIO registers to prevent problems with mismatched 158 * pin configurations. 159 */ 160 ret = regcache_sync_region(wm8994->regmap, WM8994_GPIO_1, 161 WM8994_GPIO_11); 162 if (ret != 0) 163 dev_err(dev, "Failed to restore GPIO registers: %d\n", ret); 164 165 /* In case one of the GPIOs is used as a wake input. */ 166 ret = regcache_sync_region(wm8994->regmap, 167 WM8994_INTERRUPT_STATUS_1_MASK, 168 WM8994_INTERRUPT_STATUS_1_MASK); 169 if (ret != 0) 170 dev_err(dev, "Failed to restore interrupt mask: %d\n", ret); 171 172 regcache_cache_only(wm8994->regmap, true); 173 wm8994->suspended = true; 174 175 ret = regulator_bulk_disable(wm8994->num_supplies, 176 wm8994->supplies); 177 if (ret != 0) { 178 dev_err(dev, "Failed to disable supplies: %d\n", ret); 179 return ret; 180 } 181 182 return 0; 183 } 184 185 static int wm8994_resume(struct device *dev) 186 { 187 struct wm8994 *wm8994 = dev_get_drvdata(dev); 188 int ret; 189 190 /* We may have lied to the PM core about suspending */ 191 if (!wm8994->suspended) 192 return 0; 193 194 ret = regulator_bulk_enable(wm8994->num_supplies, 195 wm8994->supplies); 196 if (ret != 0) { 197 dev_err(dev, "Failed to enable supplies: %d\n", ret); 198 return ret; 199 } 200 201 regcache_cache_only(wm8994->regmap, false); 202 ret = regcache_sync(wm8994->regmap); 203 if (ret != 0) { 204 dev_err(dev, "Failed to restore register map: %d\n", ret); 205 goto err_enable; 206 } 207 208 /* Disable LDO pulldowns while the device is active */ 209 wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2, 210 WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD, 211 0); 212 213 wm8994->suspended = false; 214 215 return 0; 216 217 err_enable: 218 regulator_bulk_disable(wm8994->num_supplies, wm8994->supplies); 219 220 return ret; 221 } 222 #endif 223 224 #ifdef CONFIG_REGULATOR 225 static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo) 226 { 227 struct wm8994_ldo_pdata *ldo_pdata; 228 229 if (!pdata) 230 return 0; 231 232 ldo_pdata = &pdata->ldo[ldo]; 233 234 if (!ldo_pdata->init_data) 235 return 0; 236 237 return ldo_pdata->init_data->num_consumer_supplies != 0; 238 } 239 #else 240 static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo) 241 { 242 return 0; 243 } 244 #endif 245 246 static const struct reg_sequence wm8994_revc_patch[] = { 247 { 0x102, 0x3 }, 248 { 0x56, 0x3 }, 249 { 0x817, 0x0 }, 250 { 0x102, 0x0 }, 251 }; 252 253 static const struct reg_sequence wm8958_reva_patch[] = { 254 { 0x102, 0x3 }, 255 { 0xcb, 0x81 }, 256 { 0x817, 0x0 }, 257 { 0x102, 0x0 }, 258 }; 259 260 static const struct reg_sequence wm1811_reva_patch[] = { 261 { 0x102, 0x3 }, 262 { 0x56, 0xc07 }, 263 { 0x5d, 0x7e }, 264 { 0x5e, 0x0 }, 265 { 0x102, 0x0 }, 266 }; 267 268 #ifdef CONFIG_OF 269 static int wm8994_set_pdata_from_of(struct wm8994 *wm8994) 270 { 271 struct device_node *np = wm8994->dev->of_node; 272 struct wm8994_pdata *pdata = &wm8994->pdata; 273 int i; 274 275 if (!np) 276 return 0; 277 278 if (of_property_read_u32_array(np, "wlf,gpio-cfg", pdata->gpio_defaults, 279 ARRAY_SIZE(pdata->gpio_defaults)) >= 0) { 280 for (i = 0; i < ARRAY_SIZE(pdata->gpio_defaults); i++) { 281 if (wm8994->pdata.gpio_defaults[i] == 0) 282 pdata->gpio_defaults[i] 283 = WM8994_CONFIGURE_GPIO; 284 } 285 } 286 287 of_property_read_u32_array(np, "wlf,micbias-cfg", pdata->micbias, 288 ARRAY_SIZE(pdata->micbias)); 289 290 pdata->lineout1_diff = true; 291 pdata->lineout2_diff = true; 292 if (of_find_property(np, "wlf,lineout1-se", NULL)) 293 pdata->lineout1_diff = false; 294 if (of_find_property(np, "wlf,lineout2-se", NULL)) 295 pdata->lineout2_diff = false; 296 297 if (of_find_property(np, "wlf,lineout1-feedback", NULL)) 298 pdata->lineout1fb = true; 299 if (of_find_property(np, "wlf,lineout2-feedback", NULL)) 300 pdata->lineout2fb = true; 301 302 if (of_find_property(np, "wlf,ldoena-always-driven", NULL)) 303 pdata->lineout2fb = true; 304 305 pdata->spkmode_pu = of_property_read_bool(np, "wlf,spkmode-pu"); 306 307 pdata->csnaddr_pd = of_property_read_bool(np, "wlf,csnaddr-pd"); 308 309 pdata->ldo[0].enable = of_get_named_gpio(np, "wlf,ldo1ena", 0); 310 if (pdata->ldo[0].enable < 0) 311 pdata->ldo[0].enable = 0; 312 313 pdata->ldo[1].enable = of_get_named_gpio(np, "wlf,ldo2ena", 0); 314 if (pdata->ldo[1].enable < 0) 315 pdata->ldo[1].enable = 0; 316 317 return 0; 318 } 319 #else 320 static int wm8994_set_pdata_from_of(struct wm8994 *wm8994) 321 { 322 return 0; 323 } 324 #endif 325 326 /* 327 * Instantiate the generic non-control parts of the device. 328 */ 329 static int wm8994_device_init(struct wm8994 *wm8994, int irq) 330 { 331 struct wm8994_pdata *pdata; 332 struct regmap_config *regmap_config; 333 const struct reg_sequence *regmap_patch = NULL; 334 const char *devname; 335 int ret, i, patch_regs = 0; 336 int pulls = 0; 337 338 if (dev_get_platdata(wm8994->dev)) { 339 pdata = dev_get_platdata(wm8994->dev); 340 wm8994->pdata = *pdata; 341 } 342 pdata = &wm8994->pdata; 343 344 ret = wm8994_set_pdata_from_of(wm8994); 345 if (ret != 0) 346 return ret; 347 348 dev_set_drvdata(wm8994->dev, wm8994); 349 350 /* Add the on-chip regulators first for bootstrapping */ 351 ret = mfd_add_devices(wm8994->dev, 0, 352 wm8994_regulator_devs, 353 ARRAY_SIZE(wm8994_regulator_devs), 354 NULL, 0, NULL); 355 if (ret != 0) { 356 dev_err(wm8994->dev, "Failed to add children: %d\n", ret); 357 goto err; 358 } 359 360 switch (wm8994->type) { 361 case WM1811: 362 wm8994->num_supplies = ARRAY_SIZE(wm1811_main_supplies); 363 break; 364 case WM8994: 365 wm8994->num_supplies = ARRAY_SIZE(wm8994_main_supplies); 366 break; 367 case WM8958: 368 wm8994->num_supplies = ARRAY_SIZE(wm8958_main_supplies); 369 break; 370 default: 371 BUG(); 372 goto err; 373 } 374 375 wm8994->supplies = devm_kcalloc(wm8994->dev, 376 wm8994->num_supplies, 377 sizeof(struct regulator_bulk_data), 378 GFP_KERNEL); 379 if (!wm8994->supplies) { 380 ret = -ENOMEM; 381 goto err; 382 } 383 384 switch (wm8994->type) { 385 case WM1811: 386 for (i = 0; i < ARRAY_SIZE(wm1811_main_supplies); i++) 387 wm8994->supplies[i].supply = wm1811_main_supplies[i]; 388 break; 389 case WM8994: 390 for (i = 0; i < ARRAY_SIZE(wm8994_main_supplies); i++) 391 wm8994->supplies[i].supply = wm8994_main_supplies[i]; 392 break; 393 case WM8958: 394 for (i = 0; i < ARRAY_SIZE(wm8958_main_supplies); i++) 395 wm8994->supplies[i].supply = wm8958_main_supplies[i]; 396 break; 397 default: 398 BUG(); 399 goto err; 400 } 401 402 /* 403 * Can't use devres helper here as some of the supplies are provided by 404 * wm8994->dev's children (regulators) and those regulators are 405 * unregistered by the devres core before the supplies are freed. 406 */ 407 ret = regulator_bulk_get(wm8994->dev, wm8994->num_supplies, 408 wm8994->supplies); 409 if (ret != 0) { 410 dev_err(wm8994->dev, "Failed to get supplies: %d\n", ret); 411 goto err; 412 } 413 414 ret = regulator_bulk_enable(wm8994->num_supplies, wm8994->supplies); 415 if (ret != 0) { 416 dev_err(wm8994->dev, "Failed to enable supplies: %d\n", ret); 417 goto err_regulator_free; 418 } 419 420 ret = wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET); 421 if (ret < 0) { 422 dev_err(wm8994->dev, "Failed to read ID register\n"); 423 goto err_enable; 424 } 425 switch (ret) { 426 case 0x1811: 427 devname = "WM1811"; 428 if (wm8994->type != WM1811) 429 dev_warn(wm8994->dev, "Device registered as type %d\n", 430 wm8994->type); 431 wm8994->type = WM1811; 432 break; 433 case 0x8994: 434 devname = "WM8994"; 435 if (wm8994->type != WM8994) 436 dev_warn(wm8994->dev, "Device registered as type %d\n", 437 wm8994->type); 438 wm8994->type = WM8994; 439 break; 440 case 0x8958: 441 devname = "WM8958"; 442 if (wm8994->type != WM8958) 443 dev_warn(wm8994->dev, "Device registered as type %d\n", 444 wm8994->type); 445 wm8994->type = WM8958; 446 break; 447 default: 448 dev_err(wm8994->dev, "Device is not a WM8994, ID is %x\n", 449 ret); 450 ret = -EINVAL; 451 goto err_enable; 452 } 453 454 ret = wm8994_reg_read(wm8994, WM8994_CHIP_REVISION); 455 if (ret < 0) { 456 dev_err(wm8994->dev, "Failed to read revision register: %d\n", 457 ret); 458 goto err_enable; 459 } 460 wm8994->revision = ret & WM8994_CHIP_REV_MASK; 461 wm8994->cust_id = (ret & WM8994_CUST_ID_MASK) >> WM8994_CUST_ID_SHIFT; 462 463 switch (wm8994->type) { 464 case WM8994: 465 switch (wm8994->revision) { 466 case 0: 467 case 1: 468 dev_warn(wm8994->dev, 469 "revision %c not fully supported\n", 470 'A' + wm8994->revision); 471 break; 472 case 2: 473 case 3: 474 default: 475 regmap_patch = wm8994_revc_patch; 476 patch_regs = ARRAY_SIZE(wm8994_revc_patch); 477 break; 478 } 479 break; 480 481 case WM8958: 482 switch (wm8994->revision) { 483 case 0: 484 regmap_patch = wm8958_reva_patch; 485 patch_regs = ARRAY_SIZE(wm8958_reva_patch); 486 break; 487 default: 488 break; 489 } 490 break; 491 492 case WM1811: 493 /* Revision C did not change the relevant layer */ 494 if (wm8994->revision > 1) 495 wm8994->revision++; 496 497 regmap_patch = wm1811_reva_patch; 498 patch_regs = ARRAY_SIZE(wm1811_reva_patch); 499 break; 500 501 default: 502 break; 503 } 504 505 dev_info(wm8994->dev, "%s revision %c CUST_ID %02x\n", devname, 506 'A' + wm8994->revision, wm8994->cust_id); 507 508 switch (wm8994->type) { 509 case WM1811: 510 regmap_config = &wm1811_regmap_config; 511 break; 512 case WM8994: 513 regmap_config = &wm8994_regmap_config; 514 break; 515 case WM8958: 516 regmap_config = &wm8958_regmap_config; 517 break; 518 default: 519 dev_err(wm8994->dev, "Unknown device type %d\n", wm8994->type); 520 ret = -EINVAL; 521 goto err_enable; 522 } 523 524 ret = regmap_reinit_cache(wm8994->regmap, regmap_config); 525 if (ret != 0) { 526 dev_err(wm8994->dev, "Failed to reinit register cache: %d\n", 527 ret); 528 goto err_enable; 529 } 530 531 /* Explicitly put the device into reset in case regulators 532 * don't get disabled in order to ensure we know the device 533 * state. 534 */ 535 ret = wm8994_reg_write(wm8994, WM8994_SOFTWARE_RESET, 536 wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET)); 537 if (ret != 0) { 538 dev_err(wm8994->dev, "Failed to reset device: %d\n", ret); 539 goto err_enable; 540 } 541 542 if (regmap_patch) { 543 ret = regmap_register_patch(wm8994->regmap, regmap_patch, 544 patch_regs); 545 if (ret != 0) { 546 dev_err(wm8994->dev, "Failed to register patch: %d\n", 547 ret); 548 goto err_enable; 549 } 550 } 551 552 wm8994->irq_base = pdata->irq_base; 553 wm8994->gpio_base = pdata->gpio_base; 554 555 /* GPIO configuration is only applied if it's non-zero */ 556 for (i = 0; i < ARRAY_SIZE(pdata->gpio_defaults); i++) { 557 if (pdata->gpio_defaults[i]) { 558 wm8994_set_bits(wm8994, WM8994_GPIO_1 + i, 559 0xffff, pdata->gpio_defaults[i]); 560 } 561 } 562 563 wm8994->ldo_ena_always_driven = pdata->ldo_ena_always_driven; 564 565 if (pdata->spkmode_pu) 566 pulls |= WM8994_SPKMODE_PU; 567 if (pdata->csnaddr_pd) 568 pulls |= WM8994_CSNADDR_PD; 569 570 /* Disable unneeded pulls */ 571 wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2, 572 WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD | 573 WM8994_SPKMODE_PU | WM8994_CSNADDR_PD, 574 pulls); 575 576 /* In some system designs where the regulators are not in use, 577 * we can achieve a small reduction in leakage currents by 578 * floating LDO outputs. This bit makes no difference if the 579 * LDOs are enabled, it only affects cases where the LDOs were 580 * in operation and are then disabled. 581 */ 582 for (i = 0; i < WM8994_NUM_LDO_REGS; i++) { 583 if (wm8994_ldo_in_use(pdata, i)) 584 wm8994_set_bits(wm8994, WM8994_LDO_1 + i, 585 WM8994_LDO1_DISCH, WM8994_LDO1_DISCH); 586 else 587 wm8994_set_bits(wm8994, WM8994_LDO_1 + i, 588 WM8994_LDO1_DISCH, 0); 589 } 590 591 wm8994_irq_init(wm8994); 592 593 ret = mfd_add_devices(wm8994->dev, -1, 594 wm8994_devs, ARRAY_SIZE(wm8994_devs), 595 NULL, 0, NULL); 596 if (ret != 0) { 597 dev_err(wm8994->dev, "Failed to add children: %d\n", ret); 598 goto err_irq; 599 } 600 601 pm_runtime_enable(wm8994->dev); 602 pm_runtime_idle(wm8994->dev); 603 604 return 0; 605 606 err_irq: 607 wm8994_irq_exit(wm8994); 608 err_enable: 609 regulator_bulk_disable(wm8994->num_supplies, 610 wm8994->supplies); 611 err_regulator_free: 612 regulator_bulk_free(wm8994->num_supplies, wm8994->supplies); 613 err: 614 mfd_remove_devices(wm8994->dev); 615 return ret; 616 } 617 618 static void wm8994_device_exit(struct wm8994 *wm8994) 619 { 620 pm_runtime_disable(wm8994->dev); 621 wm8994_irq_exit(wm8994); 622 regulator_bulk_disable(wm8994->num_supplies, wm8994->supplies); 623 regulator_bulk_free(wm8994->num_supplies, wm8994->supplies); 624 mfd_remove_devices(wm8994->dev); 625 } 626 627 static const struct of_device_id wm8994_of_match[] = { 628 { .compatible = "wlf,wm1811", .data = (void *)WM1811 }, 629 { .compatible = "wlf,wm8994", .data = (void *)WM8994 }, 630 { .compatible = "wlf,wm8958", .data = (void *)WM8958 }, 631 { } 632 }; 633 MODULE_DEVICE_TABLE(of, wm8994_of_match); 634 635 static int wm8994_i2c_probe(struct i2c_client *i2c, 636 const struct i2c_device_id *id) 637 { 638 const struct of_device_id *of_id; 639 struct wm8994 *wm8994; 640 int ret; 641 642 wm8994 = devm_kzalloc(&i2c->dev, sizeof(struct wm8994), GFP_KERNEL); 643 if (wm8994 == NULL) 644 return -ENOMEM; 645 646 i2c_set_clientdata(i2c, wm8994); 647 wm8994->dev = &i2c->dev; 648 wm8994->irq = i2c->irq; 649 650 if (i2c->dev.of_node) { 651 of_id = of_match_device(wm8994_of_match, &i2c->dev); 652 if (of_id) 653 wm8994->type = (enum wm8994_type)of_id->data; 654 } else { 655 wm8994->type = id->driver_data; 656 } 657 658 wm8994->regmap = devm_regmap_init_i2c(i2c, &wm8994_base_regmap_config); 659 if (IS_ERR(wm8994->regmap)) { 660 ret = PTR_ERR(wm8994->regmap); 661 dev_err(wm8994->dev, "Failed to allocate register map: %d\n", 662 ret); 663 return ret; 664 } 665 666 return wm8994_device_init(wm8994, i2c->irq); 667 } 668 669 static int wm8994_i2c_remove(struct i2c_client *i2c) 670 { 671 struct wm8994 *wm8994 = i2c_get_clientdata(i2c); 672 673 wm8994_device_exit(wm8994); 674 675 return 0; 676 } 677 678 static const struct i2c_device_id wm8994_i2c_id[] = { 679 { "wm1811", WM1811 }, 680 { "wm1811a", WM1811 }, 681 { "wm8994", WM8994 }, 682 { "wm8958", WM8958 }, 683 { } 684 }; 685 MODULE_DEVICE_TABLE(i2c, wm8994_i2c_id); 686 687 static const struct dev_pm_ops wm8994_pm_ops = { 688 SET_RUNTIME_PM_OPS(wm8994_suspend, wm8994_resume, NULL) 689 }; 690 691 static struct i2c_driver wm8994_i2c_driver = { 692 .driver = { 693 .name = "wm8994", 694 .pm = &wm8994_pm_ops, 695 .of_match_table = of_match_ptr(wm8994_of_match), 696 }, 697 .probe = wm8994_i2c_probe, 698 .remove = wm8994_i2c_remove, 699 .id_table = wm8994_i2c_id, 700 }; 701 702 module_i2c_driver(wm8994_i2c_driver); 703 704 MODULE_DESCRIPTION("Core support for the WM8994 audio CODEC"); 705 MODULE_LICENSE("GPL"); 706 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); 707