1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Driver for the Intel SCU IPC mechanism 4 * 5 * (C) Copyright 2008-2010,2015 Intel Corporation 6 * Author: Sreedhara DS (sreedhara.ds@intel.com) 7 * 8 * SCU running in ARC processor communicates with other entity running in IA 9 * core through IPC mechanism which in turn messaging between IA core ad SCU. 10 * SCU has two IPC mechanism IPC-1 and IPC-2. IPC-1 is used between IA32 and 11 * SCU where IPC-2 is used between P-Unit and SCU. This driver delas with 12 * IPC-1 Driver provides an API for power control unit registers (e.g. MSIC) 13 * along with other APIs. 14 */ 15 16 #include <linux/delay.h> 17 #include <linux/device.h> 18 #include <linux/errno.h> 19 #include <linux/init.h> 20 #include <linux/interrupt.h> 21 #include <linux/io.h> 22 #include <linux/module.h> 23 #include <linux/slab.h> 24 25 #include <asm/intel_scu_ipc.h> 26 27 /* IPC defines the following message types */ 28 #define IPCMSG_PCNTRL 0xff /* Power controller unit read/write */ 29 30 /* Command id associated with message IPCMSG_PCNTRL */ 31 #define IPC_CMD_PCNTRL_W 0 /* Register write */ 32 #define IPC_CMD_PCNTRL_R 1 /* Register read */ 33 #define IPC_CMD_PCNTRL_M 2 /* Register read-modify-write */ 34 35 /* 36 * IPC register summary 37 * 38 * IPC register blocks are memory mapped at fixed address of PCI BAR 0. 39 * To read or write information to the SCU, driver writes to IPC-1 memory 40 * mapped registers. The following is the IPC mechanism 41 * 42 * 1. IA core cDMI interface claims this transaction and converts it to a 43 * Transaction Layer Packet (TLP) message which is sent across the cDMI. 44 * 45 * 2. South Complex cDMI block receives this message and writes it to 46 * the IPC-1 register block, causing an interrupt to the SCU 47 * 48 * 3. SCU firmware decodes this interrupt and IPC message and the appropriate 49 * message handler is called within firmware. 50 */ 51 52 #define IPC_WWBUF_SIZE 20 /* IPC Write buffer Size */ 53 #define IPC_RWBUF_SIZE 20 /* IPC Read buffer Size */ 54 #define IPC_IOC 0x100 /* IPC command register IOC bit */ 55 56 struct intel_scu_ipc_dev { 57 struct device dev; 58 struct resource mem; 59 struct module *owner; 60 int irq; 61 void __iomem *ipc_base; 62 struct completion cmd_complete; 63 }; 64 65 #define IPC_STATUS 0x04 66 #define IPC_STATUS_IRQ BIT(2) 67 #define IPC_STATUS_ERR BIT(1) 68 #define IPC_STATUS_BUSY BIT(0) 69 70 /* 71 * IPC Write/Read Buffers: 72 * 16 byte buffer for sending and receiving data to and from SCU. 73 */ 74 #define IPC_WRITE_BUFFER 0x80 75 #define IPC_READ_BUFFER 0x90 76 77 /* Timeout in jiffies */ 78 #define IPC_TIMEOUT (5 * HZ) 79 80 static struct intel_scu_ipc_dev *ipcdev; /* Only one for now */ 81 static DEFINE_MUTEX(ipclock); /* lock used to prevent multiple call to SCU */ 82 83 static struct class intel_scu_ipc_class = { 84 .name = "intel_scu_ipc", 85 .owner = THIS_MODULE, 86 }; 87 88 /** 89 * intel_scu_ipc_dev_get() - Get SCU IPC instance 90 * 91 * The recommended new API takes SCU IPC instance as parameter and this 92 * function can be called by driver to get the instance. This also makes 93 * sure the driver providing the IPC functionality cannot be unloaded 94 * while the caller has the instance. 95 * 96 * Call intel_scu_ipc_dev_put() to release the instance. 97 * 98 * Returns %NULL if SCU IPC is not currently available. 99 */ 100 struct intel_scu_ipc_dev *intel_scu_ipc_dev_get(void) 101 { 102 struct intel_scu_ipc_dev *scu = NULL; 103 104 mutex_lock(&ipclock); 105 if (ipcdev) { 106 get_device(&ipcdev->dev); 107 /* 108 * Prevent the IPC provider from being unloaded while it 109 * is being used. 110 */ 111 if (!try_module_get(ipcdev->owner)) 112 put_device(&ipcdev->dev); 113 else 114 scu = ipcdev; 115 } 116 117 mutex_unlock(&ipclock); 118 return scu; 119 } 120 EXPORT_SYMBOL_GPL(intel_scu_ipc_dev_get); 121 122 /** 123 * intel_scu_ipc_dev_put() - Put SCU IPC instance 124 * @scu: SCU IPC instance 125 * 126 * This function releases the SCU IPC instance retrieved from 127 * intel_scu_ipc_dev_get() and allows the driver providing IPC to be 128 * unloaded. 129 */ 130 void intel_scu_ipc_dev_put(struct intel_scu_ipc_dev *scu) 131 { 132 if (scu) { 133 module_put(scu->owner); 134 put_device(&scu->dev); 135 } 136 } 137 EXPORT_SYMBOL_GPL(intel_scu_ipc_dev_put); 138 139 struct intel_scu_ipc_devres { 140 struct intel_scu_ipc_dev *scu; 141 }; 142 143 static void devm_intel_scu_ipc_dev_release(struct device *dev, void *res) 144 { 145 struct intel_scu_ipc_devres *dr = res; 146 struct intel_scu_ipc_dev *scu = dr->scu; 147 148 intel_scu_ipc_dev_put(scu); 149 } 150 151 /** 152 * devm_intel_scu_ipc_dev_get() - Allocate managed SCU IPC device 153 * @dev: Device requesting the SCU IPC device 154 * 155 * The recommended new API takes SCU IPC instance as parameter and this 156 * function can be called by driver to get the instance. This also makes 157 * sure the driver providing the IPC functionality cannot be unloaded 158 * while the caller has the instance. 159 * 160 * Returns %NULL if SCU IPC is not currently available. 161 */ 162 struct intel_scu_ipc_dev *devm_intel_scu_ipc_dev_get(struct device *dev) 163 { 164 struct intel_scu_ipc_devres *dr; 165 struct intel_scu_ipc_dev *scu; 166 167 dr = devres_alloc(devm_intel_scu_ipc_dev_release, sizeof(*dr), GFP_KERNEL); 168 if (!dr) 169 return NULL; 170 171 scu = intel_scu_ipc_dev_get(); 172 if (!scu) { 173 devres_free(dr); 174 return NULL; 175 } 176 177 dr->scu = scu; 178 devres_add(dev, dr); 179 180 return scu; 181 } 182 EXPORT_SYMBOL_GPL(devm_intel_scu_ipc_dev_get); 183 184 /* 185 * Send ipc command 186 * Command Register (Write Only): 187 * A write to this register results in an interrupt to the SCU core processor 188 * Format: 189 * |rfu2(8) | size(8) | command id(4) | rfu1(3) | ioc(1) | command(8)| 190 */ 191 static inline void ipc_command(struct intel_scu_ipc_dev *scu, u32 cmd) 192 { 193 reinit_completion(&scu->cmd_complete); 194 writel(cmd | IPC_IOC, scu->ipc_base); 195 } 196 197 /* 198 * Write ipc data 199 * IPC Write Buffer (Write Only): 200 * 16-byte buffer for sending data associated with IPC command to 201 * SCU. Size of the data is specified in the IPC_COMMAND_REG register 202 */ 203 static inline void ipc_data_writel(struct intel_scu_ipc_dev *scu, u32 data, u32 offset) 204 { 205 writel(data, scu->ipc_base + IPC_WRITE_BUFFER + offset); 206 } 207 208 /* 209 * Status Register (Read Only): 210 * Driver will read this register to get the ready/busy status of the IPC 211 * block and error status of the IPC command that was just processed by SCU 212 * Format: 213 * |rfu3(8)|error code(8)|initiator id(8)|cmd id(4)|rfu1(2)|error(1)|busy(1)| 214 */ 215 static inline u8 ipc_read_status(struct intel_scu_ipc_dev *scu) 216 { 217 return __raw_readl(scu->ipc_base + IPC_STATUS); 218 } 219 220 /* Read ipc byte data */ 221 static inline u8 ipc_data_readb(struct intel_scu_ipc_dev *scu, u32 offset) 222 { 223 return readb(scu->ipc_base + IPC_READ_BUFFER + offset); 224 } 225 226 /* Read ipc u32 data */ 227 static inline u32 ipc_data_readl(struct intel_scu_ipc_dev *scu, u32 offset) 228 { 229 return readl(scu->ipc_base + IPC_READ_BUFFER + offset); 230 } 231 232 /* Wait till scu status is busy */ 233 static inline int busy_loop(struct intel_scu_ipc_dev *scu) 234 { 235 unsigned long end = jiffies + msecs_to_jiffies(IPC_TIMEOUT); 236 237 do { 238 u32 status; 239 240 status = ipc_read_status(scu); 241 if (!(status & IPC_STATUS_BUSY)) 242 return (status & IPC_STATUS_ERR) ? -EIO : 0; 243 244 usleep_range(50, 100); 245 } while (time_before(jiffies, end)); 246 247 return -ETIMEDOUT; 248 } 249 250 /* Wait till ipc ioc interrupt is received or timeout in 3 HZ */ 251 static inline int ipc_wait_for_interrupt(struct intel_scu_ipc_dev *scu) 252 { 253 int status; 254 255 if (!wait_for_completion_timeout(&scu->cmd_complete, IPC_TIMEOUT)) 256 return -ETIMEDOUT; 257 258 status = ipc_read_status(scu); 259 if (status & IPC_STATUS_ERR) 260 return -EIO; 261 262 return 0; 263 } 264 265 static int intel_scu_ipc_check_status(struct intel_scu_ipc_dev *scu) 266 { 267 return scu->irq > 0 ? ipc_wait_for_interrupt(scu) : busy_loop(scu); 268 } 269 270 /* Read/Write power control(PMIC in Langwell, MSIC in PenWell) registers */ 271 static int pwr_reg_rdwr(struct intel_scu_ipc_dev *scu, u16 *addr, u8 *data, 272 u32 count, u32 op, u32 id) 273 { 274 int nc; 275 u32 offset = 0; 276 int err; 277 u8 cbuf[IPC_WWBUF_SIZE]; 278 u32 *wbuf = (u32 *)&cbuf; 279 280 memset(cbuf, 0, sizeof(cbuf)); 281 282 mutex_lock(&ipclock); 283 if (!scu) 284 scu = ipcdev; 285 if (!scu) { 286 mutex_unlock(&ipclock); 287 return -ENODEV; 288 } 289 290 for (nc = 0; nc < count; nc++, offset += 2) { 291 cbuf[offset] = addr[nc]; 292 cbuf[offset + 1] = addr[nc] >> 8; 293 } 294 295 if (id == IPC_CMD_PCNTRL_R) { 296 for (nc = 0, offset = 0; nc < count; nc++, offset += 4) 297 ipc_data_writel(scu, wbuf[nc], offset); 298 ipc_command(scu, (count * 2) << 16 | id << 12 | 0 << 8 | op); 299 } else if (id == IPC_CMD_PCNTRL_W) { 300 for (nc = 0; nc < count; nc++, offset += 1) 301 cbuf[offset] = data[nc]; 302 for (nc = 0, offset = 0; nc < count; nc++, offset += 4) 303 ipc_data_writel(scu, wbuf[nc], offset); 304 ipc_command(scu, (count * 3) << 16 | id << 12 | 0 << 8 | op); 305 } else if (id == IPC_CMD_PCNTRL_M) { 306 cbuf[offset] = data[0]; 307 cbuf[offset + 1] = data[1]; 308 ipc_data_writel(scu, wbuf[0], 0); /* Write wbuff */ 309 ipc_command(scu, 4 << 16 | id << 12 | 0 << 8 | op); 310 } 311 312 err = intel_scu_ipc_check_status(scu); 313 if (!err && id == IPC_CMD_PCNTRL_R) { /* Read rbuf */ 314 /* Workaround: values are read as 0 without memcpy_fromio */ 315 memcpy_fromio(cbuf, scu->ipc_base + 0x90, 16); 316 for (nc = 0; nc < count; nc++) 317 data[nc] = ipc_data_readb(scu, nc); 318 } 319 mutex_unlock(&ipclock); 320 return err; 321 } 322 323 /** 324 * intel_scu_ipc_dev_ioread8() - Read a byte via the SCU 325 * @scu: Optional SCU IPC instance 326 * @addr: Register on SCU 327 * @data: Return pointer for read byte 328 * 329 * Read a single register. Returns %0 on success or an error code. All 330 * locking between SCU accesses is handled for the caller. 331 * 332 * This function may sleep. 333 */ 334 int intel_scu_ipc_dev_ioread8(struct intel_scu_ipc_dev *scu, u16 addr, u8 *data) 335 { 336 return pwr_reg_rdwr(scu, &addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R); 337 } 338 EXPORT_SYMBOL(intel_scu_ipc_dev_ioread8); 339 340 /** 341 * intel_scu_ipc_dev_iowrite8() - Write a byte via the SCU 342 * @scu: Optional SCU IPC instance 343 * @addr: Register on SCU 344 * @data: Byte to write 345 * 346 * Write a single register. Returns %0 on success or an error code. All 347 * locking between SCU accesses is handled for the caller. 348 * 349 * This function may sleep. 350 */ 351 int intel_scu_ipc_dev_iowrite8(struct intel_scu_ipc_dev *scu, u16 addr, u8 data) 352 { 353 return pwr_reg_rdwr(scu, &addr, &data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W); 354 } 355 EXPORT_SYMBOL(intel_scu_ipc_dev_iowrite8); 356 357 /** 358 * intel_scu_ipc_dev_readv() - Read a set of registers 359 * @scu: Optional SCU IPC instance 360 * @addr: Register list 361 * @data: Bytes to return 362 * @len: Length of array 363 * 364 * Read registers. Returns %0 on success or an error code. All locking 365 * between SCU accesses is handled for the caller. 366 * 367 * The largest array length permitted by the hardware is 5 items. 368 * 369 * This function may sleep. 370 */ 371 int intel_scu_ipc_dev_readv(struct intel_scu_ipc_dev *scu, u16 *addr, u8 *data, 372 size_t len) 373 { 374 return pwr_reg_rdwr(scu, addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R); 375 } 376 EXPORT_SYMBOL(intel_scu_ipc_dev_readv); 377 378 /** 379 * intel_scu_ipc_dev_writev() - Write a set of registers 380 * @scu: Optional SCU IPC instance 381 * @addr: Register list 382 * @data: Bytes to write 383 * @len: Length of array 384 * 385 * Write registers. Returns %0 on success or an error code. All locking 386 * between SCU accesses is handled for the caller. 387 * 388 * The largest array length permitted by the hardware is 5 items. 389 * 390 * This function may sleep. 391 */ 392 int intel_scu_ipc_dev_writev(struct intel_scu_ipc_dev *scu, u16 *addr, u8 *data, 393 size_t len) 394 { 395 return pwr_reg_rdwr(scu, addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W); 396 } 397 EXPORT_SYMBOL(intel_scu_ipc_dev_writev); 398 399 /** 400 * intel_scu_ipc_dev_update() - Update a register 401 * @scu: Optional SCU IPC instance 402 * @addr: Register address 403 * @data: Bits to update 404 * @mask: Mask of bits to update 405 * 406 * Read-modify-write power control unit register. The first data argument 407 * must be register value and second is mask value mask is a bitmap that 408 * indicates which bits to update. %0 = masked. Don't modify this bit, %1 = 409 * modify this bit. returns %0 on success or an error code. 410 * 411 * This function may sleep. Locking between SCU accesses is handled 412 * for the caller. 413 */ 414 int intel_scu_ipc_dev_update(struct intel_scu_ipc_dev *scu, u16 addr, u8 data, 415 u8 mask) 416 { 417 u8 tmp[2] = { data, mask }; 418 return pwr_reg_rdwr(scu, &addr, tmp, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_M); 419 } 420 EXPORT_SYMBOL(intel_scu_ipc_dev_update); 421 422 /** 423 * intel_scu_ipc_dev_simple_command() - Send a simple command 424 * @scu: Optional SCU IPC instance 425 * @cmd: Command 426 * @sub: Sub type 427 * 428 * Issue a simple command to the SCU. Do not use this interface if you must 429 * then access data as any data values may be overwritten by another SCU 430 * access by the time this function returns. 431 * 432 * This function may sleep. Locking for SCU accesses is handled for the 433 * caller. 434 */ 435 int intel_scu_ipc_dev_simple_command(struct intel_scu_ipc_dev *scu, int cmd, 436 int sub) 437 { 438 u32 cmdval; 439 int err; 440 441 mutex_lock(&ipclock); 442 if (!scu) 443 scu = ipcdev; 444 if (!scu) { 445 mutex_unlock(&ipclock); 446 return -ENODEV; 447 } 448 scu = ipcdev; 449 cmdval = sub << 12 | cmd; 450 ipc_command(scu, cmdval); 451 err = intel_scu_ipc_check_status(scu); 452 mutex_unlock(&ipclock); 453 if (err) 454 dev_err(&scu->dev, "IPC command %#x failed with %d\n", cmdval, err); 455 return err; 456 } 457 EXPORT_SYMBOL(intel_scu_ipc_dev_simple_command); 458 459 /** 460 * intel_scu_ipc_dev_command_with_size() - Command with data 461 * @scu: Optional SCU IPC instance 462 * @cmd: Command 463 * @sub: Sub type 464 * @in: Input data 465 * @inlen: Input length in bytes 466 * @size: Input size written to the IPC command register in whatever 467 * units (dword, byte) the particular firmware requires. Normally 468 * should be the same as @inlen. 469 * @out: Output data 470 * @outlen: Output length in bytes 471 * 472 * Issue a command to the SCU which involves data transfers. Do the 473 * data copies under the lock but leave it for the caller to interpret. 474 */ 475 int intel_scu_ipc_dev_command_with_size(struct intel_scu_ipc_dev *scu, int cmd, 476 int sub, const void *in, size_t inlen, 477 size_t size, void *out, size_t outlen) 478 { 479 size_t outbuflen = DIV_ROUND_UP(outlen, sizeof(u32)); 480 size_t inbuflen = DIV_ROUND_UP(inlen, sizeof(u32)); 481 u32 cmdval, inbuf[4] = {}; 482 int i, err; 483 484 if (inbuflen > 4 || outbuflen > 4) 485 return -EINVAL; 486 487 mutex_lock(&ipclock); 488 if (!scu) 489 scu = ipcdev; 490 if (!scu) { 491 mutex_unlock(&ipclock); 492 return -ENODEV; 493 } 494 495 memcpy(inbuf, in, inlen); 496 for (i = 0; i < inbuflen; i++) 497 ipc_data_writel(scu, inbuf[i], 4 * i); 498 499 cmdval = (size << 16) | (sub << 12) | cmd; 500 ipc_command(scu, cmdval); 501 err = intel_scu_ipc_check_status(scu); 502 503 if (!err) { 504 u32 outbuf[4] = {}; 505 506 for (i = 0; i < outbuflen; i++) 507 outbuf[i] = ipc_data_readl(scu, 4 * i); 508 509 memcpy(out, outbuf, outlen); 510 } 511 512 mutex_unlock(&ipclock); 513 if (err) 514 dev_err(&scu->dev, "IPC command %#x failed with %d\n", cmdval, err); 515 return err; 516 } 517 EXPORT_SYMBOL(intel_scu_ipc_dev_command_with_size); 518 519 /* 520 * Interrupt handler gets called when ioc bit of IPC_COMMAND_REG set to 1 521 * When ioc bit is set to 1, caller api must wait for interrupt handler called 522 * which in turn unlocks the caller api. Currently this is not used 523 * 524 * This is edge triggered so we need take no action to clear anything 525 */ 526 static irqreturn_t ioc(int irq, void *dev_id) 527 { 528 struct intel_scu_ipc_dev *scu = dev_id; 529 int status = ipc_read_status(scu); 530 531 writel(status | IPC_STATUS_IRQ, scu->ipc_base + IPC_STATUS); 532 complete(&scu->cmd_complete); 533 534 return IRQ_HANDLED; 535 } 536 537 static void intel_scu_ipc_release(struct device *dev) 538 { 539 struct intel_scu_ipc_dev *scu; 540 541 scu = container_of(dev, struct intel_scu_ipc_dev, dev); 542 if (scu->irq > 0) 543 free_irq(scu->irq, scu); 544 iounmap(scu->ipc_base); 545 release_mem_region(scu->mem.start, resource_size(&scu->mem)); 546 kfree(scu); 547 } 548 549 /** 550 * __intel_scu_ipc_register() - Register SCU IPC device 551 * @parent: Parent device 552 * @scu_data: Data used to configure SCU IPC 553 * @owner: Module registering the SCU IPC device 554 * 555 * Call this function to register SCU IPC mechanism under @parent. 556 * Returns pointer to the new SCU IPC device or ERR_PTR() in case of 557 * failure. The caller may use the returned instance if it needs to do 558 * SCU IPC calls itself. 559 */ 560 struct intel_scu_ipc_dev * 561 __intel_scu_ipc_register(struct device *parent, 562 const struct intel_scu_ipc_data *scu_data, 563 struct module *owner) 564 { 565 int err; 566 struct intel_scu_ipc_dev *scu; 567 void __iomem *ipc_base; 568 569 mutex_lock(&ipclock); 570 /* We support only one IPC */ 571 if (ipcdev) { 572 err = -EBUSY; 573 goto err_unlock; 574 } 575 576 scu = kzalloc(sizeof(*scu), GFP_KERNEL); 577 if (!scu) { 578 err = -ENOMEM; 579 goto err_unlock; 580 } 581 582 scu->owner = owner; 583 scu->dev.parent = parent; 584 scu->dev.class = &intel_scu_ipc_class; 585 scu->dev.release = intel_scu_ipc_release; 586 dev_set_name(&scu->dev, "intel_scu_ipc"); 587 588 if (!request_mem_region(scu_data->mem.start, resource_size(&scu_data->mem), 589 "intel_scu_ipc")) { 590 err = -EBUSY; 591 goto err_free; 592 } 593 594 ipc_base = ioremap(scu_data->mem.start, resource_size(&scu_data->mem)); 595 if (!ipc_base) { 596 err = -ENOMEM; 597 goto err_release; 598 } 599 600 scu->ipc_base = ipc_base; 601 scu->mem = scu_data->mem; 602 scu->irq = scu_data->irq; 603 init_completion(&scu->cmd_complete); 604 605 if (scu->irq > 0) { 606 err = request_irq(scu->irq, ioc, 0, "intel_scu_ipc", scu); 607 if (err) 608 goto err_unmap; 609 } 610 611 /* 612 * After this point intel_scu_ipc_release() takes care of 613 * releasing the SCU IPC resources once refcount drops to zero. 614 */ 615 err = device_register(&scu->dev); 616 if (err) { 617 put_device(&scu->dev); 618 goto err_unlock; 619 } 620 621 /* Assign device at last */ 622 ipcdev = scu; 623 mutex_unlock(&ipclock); 624 625 return scu; 626 627 err_unmap: 628 iounmap(ipc_base); 629 err_release: 630 release_mem_region(scu_data->mem.start, resource_size(&scu_data->mem)); 631 err_free: 632 kfree(scu); 633 err_unlock: 634 mutex_unlock(&ipclock); 635 636 return ERR_PTR(err); 637 } 638 EXPORT_SYMBOL_GPL(__intel_scu_ipc_register); 639 640 /** 641 * intel_scu_ipc_unregister() - Unregister SCU IPC 642 * @scu: SCU IPC handle 643 * 644 * This unregisters the SCU IPC device and releases the acquired 645 * resources once the refcount goes to zero. 646 */ 647 void intel_scu_ipc_unregister(struct intel_scu_ipc_dev *scu) 648 { 649 mutex_lock(&ipclock); 650 if (!WARN_ON(!ipcdev)) { 651 ipcdev = NULL; 652 device_unregister(&scu->dev); 653 } 654 mutex_unlock(&ipclock); 655 } 656 EXPORT_SYMBOL_GPL(intel_scu_ipc_unregister); 657 658 static void devm_intel_scu_ipc_unregister(struct device *dev, void *res) 659 { 660 struct intel_scu_ipc_devres *dr = res; 661 struct intel_scu_ipc_dev *scu = dr->scu; 662 663 intel_scu_ipc_unregister(scu); 664 } 665 666 /** 667 * __devm_intel_scu_ipc_register() - Register managed SCU IPC device 668 * @parent: Parent device 669 * @scu_data: Data used to configure SCU IPC 670 * @owner: Module registering the SCU IPC device 671 * 672 * Call this function to register managed SCU IPC mechanism under 673 * @parent. Returns pointer to the new SCU IPC device or ERR_PTR() in 674 * case of failure. The caller may use the returned instance if it needs 675 * to do SCU IPC calls itself. 676 */ 677 struct intel_scu_ipc_dev * 678 __devm_intel_scu_ipc_register(struct device *parent, 679 const struct intel_scu_ipc_data *scu_data, 680 struct module *owner) 681 { 682 struct intel_scu_ipc_devres *dr; 683 struct intel_scu_ipc_dev *scu; 684 685 dr = devres_alloc(devm_intel_scu_ipc_unregister, sizeof(*dr), GFP_KERNEL); 686 if (!dr) 687 return NULL; 688 689 scu = __intel_scu_ipc_register(parent, scu_data, owner); 690 if (IS_ERR(scu)) { 691 devres_free(dr); 692 return scu; 693 } 694 695 dr->scu = scu; 696 devres_add(parent, dr); 697 698 return scu; 699 } 700 EXPORT_SYMBOL_GPL(__devm_intel_scu_ipc_register); 701 702 static int __init intel_scu_ipc_init(void) 703 { 704 return class_register(&intel_scu_ipc_class); 705 } 706 subsys_initcall(intel_scu_ipc_init); 707 708 static void __exit intel_scu_ipc_exit(void) 709 { 710 class_unregister(&intel_scu_ipc_class); 711 } 712 module_exit(intel_scu_ipc_exit); 713