1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2016 Robert Jarzmik <robert.jarzmik@free.fr> 4 */ 5 6 #include <linux/module.h> 7 #include <linux/bitops.h> 8 #include <linux/clk.h> 9 #include <linux/device.h> 10 #include <linux/idr.h> 11 #include <linux/list.h> 12 #include <linux/mutex.h> 13 #include <linux/of.h> 14 #include <linux/pm.h> 15 #include <linux/pm_runtime.h> 16 #include <linux/slab.h> 17 #include <linux/sysfs.h> 18 #include <sound/ac97_codec.h> 19 #include <sound/ac97/codec.h> 20 #include <sound/ac97/controller.h> 21 #include <sound/ac97/regs.h> 22 23 #include "ac97_core.h" 24 25 /* 26 * Protects ac97_controllers and each ac97_controller structure. 27 */ 28 static DEFINE_MUTEX(ac97_controllers_mutex); 29 static DEFINE_IDR(ac97_adapter_idr); 30 static LIST_HEAD(ac97_controllers); 31 32 static inline struct ac97_controller* 33 to_ac97_controller(struct device *ac97_adapter) 34 { 35 return container_of(ac97_adapter, struct ac97_controller, adap); 36 } 37 38 static int ac97_unbound_ctrl_write(struct ac97_controller *adrv, int slot, 39 unsigned short reg, unsigned short val) 40 { 41 return -ENODEV; 42 } 43 44 static int ac97_unbound_ctrl_read(struct ac97_controller *adrv, int slot, 45 unsigned short reg) 46 { 47 return -ENODEV; 48 } 49 50 static const struct ac97_controller_ops ac97_unbound_ctrl_ops = { 51 .write = ac97_unbound_ctrl_write, 52 .read = ac97_unbound_ctrl_read, 53 }; 54 55 static struct ac97_controller ac97_unbound_ctrl = { 56 .ops = &ac97_unbound_ctrl_ops, 57 }; 58 59 static struct ac97_codec_device * 60 ac97_codec_find(struct ac97_controller *ac97_ctrl, unsigned int codec_num) 61 { 62 if (codec_num >= AC97_BUS_MAX_CODECS) 63 return ERR_PTR(-EINVAL); 64 65 return ac97_ctrl->codecs[codec_num]; 66 } 67 68 static struct device_node * 69 ac97_of_get_child_device(struct ac97_controller *ac97_ctrl, int idx, 70 unsigned int vendor_id) 71 { 72 struct device_node *node; 73 u32 reg; 74 char compat[] = "ac97,0000,0000"; 75 76 snprintf(compat, sizeof(compat), "ac97,%04x,%04x", 77 vendor_id >> 16, vendor_id & 0xffff); 78 79 for_each_child_of_node(ac97_ctrl->parent->of_node, node) { 80 if ((idx != of_property_read_u32(node, "reg", ®)) || 81 !of_device_is_compatible(node, compat)) 82 continue; 83 return node; 84 } 85 86 return NULL; 87 } 88 89 static void ac97_codec_release(struct device *dev) 90 { 91 struct ac97_codec_device *adev; 92 struct ac97_controller *ac97_ctrl; 93 94 adev = to_ac97_device(dev); 95 ac97_ctrl = adev->ac97_ctrl; 96 ac97_ctrl->codecs[adev->num] = NULL; 97 of_node_put(dev->of_node); 98 kfree(adev); 99 } 100 101 static int ac97_codec_add(struct ac97_controller *ac97_ctrl, int idx, 102 unsigned int vendor_id) 103 { 104 struct ac97_codec_device *codec; 105 int ret; 106 107 codec = kzalloc(sizeof(*codec), GFP_KERNEL); 108 if (!codec) 109 return -ENOMEM; 110 ac97_ctrl->codecs[idx] = codec; 111 codec->vendor_id = vendor_id; 112 codec->dev.release = ac97_codec_release; 113 codec->dev.bus = &ac97_bus_type; 114 codec->dev.parent = &ac97_ctrl->adap; 115 codec->num = idx; 116 codec->ac97_ctrl = ac97_ctrl; 117 118 device_initialize(&codec->dev); 119 dev_set_name(&codec->dev, "%s:%u", dev_name(ac97_ctrl->parent), idx); 120 codec->dev.of_node = ac97_of_get_child_device(ac97_ctrl, idx, 121 vendor_id); 122 123 ret = device_add(&codec->dev); 124 if (ret) { 125 put_device(&codec->dev); 126 return ret; 127 } 128 129 return 0; 130 } 131 132 unsigned int snd_ac97_bus_scan_one(struct ac97_controller *adrv, 133 unsigned int codec_num) 134 { 135 unsigned short vid1, vid2; 136 int ret; 137 138 ret = adrv->ops->read(adrv, codec_num, AC97_VENDOR_ID1); 139 vid1 = (ret & 0xffff); 140 if (ret < 0) 141 return 0; 142 143 ret = adrv->ops->read(adrv, codec_num, AC97_VENDOR_ID2); 144 vid2 = (ret & 0xffff); 145 if (ret < 0) 146 return 0; 147 148 dev_dbg(&adrv->adap, "%s(codec_num=%u): vendor_id=0x%08x\n", 149 __func__, codec_num, AC97_ID(vid1, vid2)); 150 return AC97_ID(vid1, vid2); 151 } 152 153 static int ac97_bus_scan(struct ac97_controller *ac97_ctrl) 154 { 155 int ret, i; 156 unsigned int vendor_id; 157 158 for (i = 0; i < AC97_BUS_MAX_CODECS; i++) { 159 if (ac97_codec_find(ac97_ctrl, i)) 160 continue; 161 if (!(ac97_ctrl->slots_available & BIT(i))) 162 continue; 163 vendor_id = snd_ac97_bus_scan_one(ac97_ctrl, i); 164 if (!vendor_id) 165 continue; 166 167 ret = ac97_codec_add(ac97_ctrl, i, vendor_id); 168 if (ret < 0) 169 return ret; 170 } 171 return 0; 172 } 173 174 static int ac97_bus_reset(struct ac97_controller *ac97_ctrl) 175 { 176 ac97_ctrl->ops->reset(ac97_ctrl); 177 178 return 0; 179 } 180 181 /** 182 * snd_ac97_codec_driver_register - register an AC97 codec driver 183 * @dev: AC97 driver codec to register 184 * 185 * Register an AC97 codec driver to the ac97 bus driver, aka. the AC97 digital 186 * controller. 187 * 188 * Returns 0 on success or error code 189 */ 190 int snd_ac97_codec_driver_register(struct ac97_codec_driver *drv) 191 { 192 drv->driver.bus = &ac97_bus_type; 193 return driver_register(&drv->driver); 194 } 195 EXPORT_SYMBOL_GPL(snd_ac97_codec_driver_register); 196 197 /** 198 * snd_ac97_codec_driver_unregister - unregister an AC97 codec driver 199 * @dev: AC97 codec driver to unregister 200 * 201 * Unregister a previously registered ac97 codec driver. 202 */ 203 void snd_ac97_codec_driver_unregister(struct ac97_codec_driver *drv) 204 { 205 driver_unregister(&drv->driver); 206 } 207 EXPORT_SYMBOL_GPL(snd_ac97_codec_driver_unregister); 208 209 /** 210 * snd_ac97_codec_get_platdata - get platform_data 211 * @adev: the ac97 codec device 212 * 213 * For legacy platforms, in order to have platform_data in codec drivers 214 * available, while ac97 device are auto-created upon probe, this retrieves the 215 * platdata which was setup on ac97 controller registration. 216 * 217 * Returns the platform data pointer 218 */ 219 void *snd_ac97_codec_get_platdata(const struct ac97_codec_device *adev) 220 { 221 struct ac97_controller *ac97_ctrl = adev->ac97_ctrl; 222 223 return ac97_ctrl->codecs_pdata[adev->num]; 224 } 225 EXPORT_SYMBOL_GPL(snd_ac97_codec_get_platdata); 226 227 static void ac97_ctrl_codecs_unregister(struct ac97_controller *ac97_ctrl) 228 { 229 int i; 230 231 for (i = 0; i < AC97_BUS_MAX_CODECS; i++) 232 if (ac97_ctrl->codecs[i]) { 233 ac97_ctrl->codecs[i]->ac97_ctrl = &ac97_unbound_ctrl; 234 device_unregister(&ac97_ctrl->codecs[i]->dev); 235 } 236 } 237 238 static ssize_t cold_reset_store(struct device *dev, 239 struct device_attribute *attr, const char *buf, 240 size_t len) 241 { 242 struct ac97_controller *ac97_ctrl; 243 244 mutex_lock(&ac97_controllers_mutex); 245 ac97_ctrl = to_ac97_controller(dev); 246 ac97_ctrl->ops->reset(ac97_ctrl); 247 mutex_unlock(&ac97_controllers_mutex); 248 return len; 249 } 250 static DEVICE_ATTR_WO(cold_reset); 251 252 static ssize_t warm_reset_store(struct device *dev, 253 struct device_attribute *attr, const char *buf, 254 size_t len) 255 { 256 struct ac97_controller *ac97_ctrl; 257 258 if (!dev) 259 return -ENODEV; 260 261 mutex_lock(&ac97_controllers_mutex); 262 ac97_ctrl = to_ac97_controller(dev); 263 ac97_ctrl->ops->warm_reset(ac97_ctrl); 264 mutex_unlock(&ac97_controllers_mutex); 265 return len; 266 } 267 static DEVICE_ATTR_WO(warm_reset); 268 269 static struct attribute *ac97_controller_device_attrs[] = { 270 &dev_attr_cold_reset.attr, 271 &dev_attr_warm_reset.attr, 272 NULL 273 }; 274 275 static const struct attribute_group ac97_adapter_attr_group = { 276 .name = "ac97_operations", 277 .attrs = ac97_controller_device_attrs, 278 }; 279 280 static const struct attribute_group *ac97_adapter_groups[] = { 281 &ac97_adapter_attr_group, 282 NULL, 283 }; 284 285 static void ac97_del_adapter(struct ac97_controller *ac97_ctrl) 286 { 287 mutex_lock(&ac97_controllers_mutex); 288 ac97_ctrl_codecs_unregister(ac97_ctrl); 289 list_del(&ac97_ctrl->controllers); 290 mutex_unlock(&ac97_controllers_mutex); 291 292 device_unregister(&ac97_ctrl->adap); 293 } 294 295 static void ac97_adapter_release(struct device *dev) 296 { 297 struct ac97_controller *ac97_ctrl; 298 299 ac97_ctrl = to_ac97_controller(dev); 300 idr_remove(&ac97_adapter_idr, ac97_ctrl->nr); 301 dev_dbg(&ac97_ctrl->adap, "adapter unregistered by %s\n", 302 dev_name(ac97_ctrl->parent)); 303 } 304 305 static const struct device_type ac97_adapter_type = { 306 .groups = ac97_adapter_groups, 307 .release = ac97_adapter_release, 308 }; 309 310 static int ac97_add_adapter(struct ac97_controller *ac97_ctrl) 311 { 312 int ret; 313 314 mutex_lock(&ac97_controllers_mutex); 315 ret = idr_alloc(&ac97_adapter_idr, ac97_ctrl, 0, 0, GFP_KERNEL); 316 ac97_ctrl->nr = ret; 317 if (ret >= 0) { 318 dev_set_name(&ac97_ctrl->adap, "ac97-%d", ret); 319 ac97_ctrl->adap.type = &ac97_adapter_type; 320 ac97_ctrl->adap.parent = ac97_ctrl->parent; 321 ret = device_register(&ac97_ctrl->adap); 322 if (ret) 323 put_device(&ac97_ctrl->adap); 324 } 325 if (!ret) 326 list_add(&ac97_ctrl->controllers, &ac97_controllers); 327 mutex_unlock(&ac97_controllers_mutex); 328 329 if (!ret) 330 dev_dbg(&ac97_ctrl->adap, "adapter registered by %s\n", 331 dev_name(ac97_ctrl->parent)); 332 return ret; 333 } 334 335 /** 336 * snd_ac97_controller_register - register an ac97 controller 337 * @ops: the ac97 bus operations 338 * @dev: the device providing the ac97 DC function 339 * @slots_available: mask of the ac97 codecs that can be scanned and probed 340 * bit0 => codec 0, bit1 => codec 1 ... bit 3 => codec 3 341 * 342 * Register a digital controller which can control up to 4 ac97 codecs. This is 343 * the controller side of the AC97 AC-link, while the slave side are the codecs. 344 * 345 * Returns a valid controller upon success, negative pointer value upon error 346 */ 347 struct ac97_controller *snd_ac97_controller_register( 348 const struct ac97_controller_ops *ops, struct device *dev, 349 unsigned short slots_available, void **codecs_pdata) 350 { 351 struct ac97_controller *ac97_ctrl; 352 int ret, i; 353 354 ac97_ctrl = kzalloc(sizeof(*ac97_ctrl), GFP_KERNEL); 355 if (!ac97_ctrl) 356 return ERR_PTR(-ENOMEM); 357 358 for (i = 0; i < AC97_BUS_MAX_CODECS && codecs_pdata; i++) 359 ac97_ctrl->codecs_pdata[i] = codecs_pdata[i]; 360 361 ac97_ctrl->ops = ops; 362 ac97_ctrl->slots_available = slots_available; 363 ac97_ctrl->parent = dev; 364 ret = ac97_add_adapter(ac97_ctrl); 365 366 if (ret) 367 goto err; 368 ac97_bus_reset(ac97_ctrl); 369 ac97_bus_scan(ac97_ctrl); 370 371 return ac97_ctrl; 372 err: 373 kfree(ac97_ctrl); 374 return ERR_PTR(ret); 375 } 376 EXPORT_SYMBOL_GPL(snd_ac97_controller_register); 377 378 /** 379 * snd_ac97_controller_unregister - unregister an ac97 controller 380 * @ac97_ctrl: the device previously provided to ac97_controller_register() 381 * 382 */ 383 void snd_ac97_controller_unregister(struct ac97_controller *ac97_ctrl) 384 { 385 ac97_del_adapter(ac97_ctrl); 386 } 387 EXPORT_SYMBOL_GPL(snd_ac97_controller_unregister); 388 389 #ifdef CONFIG_PM 390 static int ac97_pm_runtime_suspend(struct device *dev) 391 { 392 struct ac97_codec_device *codec = to_ac97_device(dev); 393 int ret = pm_generic_runtime_suspend(dev); 394 395 if (ret == 0 && dev->driver) { 396 if (pm_runtime_is_irq_safe(dev)) 397 clk_disable(codec->clk); 398 else 399 clk_disable_unprepare(codec->clk); 400 } 401 402 return ret; 403 } 404 405 static int ac97_pm_runtime_resume(struct device *dev) 406 { 407 struct ac97_codec_device *codec = to_ac97_device(dev); 408 int ret; 409 410 if (dev->driver) { 411 if (pm_runtime_is_irq_safe(dev)) 412 ret = clk_enable(codec->clk); 413 else 414 ret = clk_prepare_enable(codec->clk); 415 if (ret) 416 return ret; 417 } 418 419 return pm_generic_runtime_resume(dev); 420 } 421 #endif /* CONFIG_PM */ 422 423 static const struct dev_pm_ops ac97_pm = { 424 .suspend = pm_generic_suspend, 425 .resume = pm_generic_resume, 426 .freeze = pm_generic_freeze, 427 .thaw = pm_generic_thaw, 428 .poweroff = pm_generic_poweroff, 429 .restore = pm_generic_restore, 430 SET_RUNTIME_PM_OPS( 431 ac97_pm_runtime_suspend, 432 ac97_pm_runtime_resume, 433 NULL) 434 }; 435 436 static int ac97_get_enable_clk(struct ac97_codec_device *adev) 437 { 438 int ret; 439 440 adev->clk = clk_get(&adev->dev, "ac97_clk"); 441 if (IS_ERR(adev->clk)) 442 return PTR_ERR(adev->clk); 443 444 ret = clk_prepare_enable(adev->clk); 445 if (ret) 446 clk_put(adev->clk); 447 448 return ret; 449 } 450 451 static void ac97_put_disable_clk(struct ac97_codec_device *adev) 452 { 453 clk_disable_unprepare(adev->clk); 454 clk_put(adev->clk); 455 } 456 457 static ssize_t vendor_id_show(struct device *dev, 458 struct device_attribute *attr, char *buf) 459 { 460 struct ac97_codec_device *codec = to_ac97_device(dev); 461 462 return sysfs_emit(buf, "%08x", codec->vendor_id); 463 } 464 static DEVICE_ATTR_RO(vendor_id); 465 466 static struct attribute *ac97_dev_attrs[] = { 467 &dev_attr_vendor_id.attr, 468 NULL, 469 }; 470 ATTRIBUTE_GROUPS(ac97_dev); 471 472 static int ac97_bus_match(struct device *dev, const struct device_driver *drv) 473 { 474 struct ac97_codec_device *adev = to_ac97_device(dev); 475 const struct ac97_codec_driver *adrv = to_ac97_driver(drv); 476 const struct ac97_id *id = adrv->id_table; 477 int i = 0; 478 479 if (adev->vendor_id == 0x0 || adev->vendor_id == 0xffffffff) 480 return false; 481 482 do { 483 if (ac97_ids_match(id[i].id, adev->vendor_id, id[i].mask)) 484 return true; 485 } while (id[i++].id); 486 487 return false; 488 } 489 490 static int ac97_bus_probe(struct device *dev) 491 { 492 struct ac97_codec_device *adev = to_ac97_device(dev); 493 struct ac97_codec_driver *adrv = to_ac97_driver(dev->driver); 494 int ret; 495 496 ret = ac97_get_enable_clk(adev); 497 if (ret) 498 return ret; 499 500 pm_runtime_get_noresume(dev); 501 pm_runtime_set_active(dev); 502 pm_runtime_enable(dev); 503 504 ret = adrv->probe(adev); 505 if (ret == 0) 506 return 0; 507 508 pm_runtime_disable(dev); 509 pm_runtime_set_suspended(dev); 510 pm_runtime_put_noidle(dev); 511 ac97_put_disable_clk(adev); 512 513 return ret; 514 } 515 516 static void ac97_bus_remove(struct device *dev) 517 { 518 struct ac97_codec_device *adev = to_ac97_device(dev); 519 struct ac97_codec_driver *adrv = to_ac97_driver(dev->driver); 520 int ret; 521 522 ret = pm_runtime_resume_and_get(dev); 523 if (ret < 0) 524 return; 525 526 adrv->remove(adev); 527 pm_runtime_put_noidle(dev); 528 ac97_put_disable_clk(adev); 529 530 pm_runtime_disable(dev); 531 } 532 533 const struct bus_type ac97_bus_type = { 534 .name = "ac97bus", 535 .dev_groups = ac97_dev_groups, 536 .match = ac97_bus_match, 537 .pm = &ac97_pm, 538 .probe = ac97_bus_probe, 539 .remove = ac97_bus_remove, 540 }; 541 542 static int __init ac97_bus_init(void) 543 { 544 return bus_register(&ac97_bus_type); 545 } 546 subsys_initcall(ac97_bus_init); 547 548 static void __exit ac97_bus_exit(void) 549 { 550 bus_unregister(&ac97_bus_type); 551 } 552 module_exit(ac97_bus_exit); 553 554 MODULE_DESCRIPTION("AC97 bus interface"); 555 MODULE_LICENSE("GPL"); 556 MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>"); 557