1// SPDX-License-Identifier: GPL-2.0+ 2/* 3 * Copyright (C) 2018 Exceet Electronics GmbH 4 * Copyright (C) 2018 Bootlin 5 * 6 * Author: Boris Brezillon <boris.brezillon@bootlin.com> 7 */ 8#include <linux/dmaengine.h> 9#include <linux/iopoll.h> 10#include <linux/pm_runtime.h> 11#include <linux/spi/spi.h> 12#include <linux/spi/spi-mem.h> 13#include <linux/sched/task_stack.h> 14 15#include "internals.h" 16 17#define SPI_MEM_MAX_BUSWIDTH 8 18 19/** 20 * spi_controller_dma_map_mem_op_data() - DMA-map the buffer attached to a 21 * memory operation 22 * @ctlr: the SPI controller requesting this dma_map() 23 * @op: the memory operation containing the buffer to map 24 * @sgt: a pointer to a non-initialized sg_table that will be filled by this 25 * function 26 * 27 * Some controllers might want to do DMA on the data buffer embedded in @op. 28 * This helper prepares everything for you and provides a ready-to-use 29 * sg_table. This function is not intended to be called from spi drivers. 30 * Only SPI controller drivers should use it. 31 * Note that the caller must ensure the memory region pointed by 32 * op->data.buf.{in,out} is DMA-able before calling this function. 33 * 34 * Return: 0 in case of success, a negative error code otherwise. 35 */ 36int spi_controller_dma_map_mem_op_data(struct spi_controller *ctlr, 37 const struct spi_mem_op *op, 38 struct sg_table *sgt) 39{ 40 struct device *dmadev; 41 42 if (!op->data.nbytes) 43 return -EINVAL; 44 45 if (op->data.dir == SPI_MEM_DATA_OUT && ctlr->dma_tx) 46 dmadev = ctlr->dma_tx->device->dev; 47 else if (op->data.dir == SPI_MEM_DATA_IN && ctlr->dma_rx) 48 dmadev = ctlr->dma_rx->device->dev; 49 else 50 dmadev = ctlr->dev.parent; 51 52 if (!dmadev) 53 return -EINVAL; 54 55 return spi_map_buf(ctlr, dmadev, sgt, op->data.buf.in, op->data.nbytes, 56 op->data.dir == SPI_MEM_DATA_IN ? 57 DMA_FROM_DEVICE : DMA_TO_DEVICE); 58} 59EXPORT_SYMBOL_GPL(spi_controller_dma_map_mem_op_data); 60 61/** 62 * spi_controller_dma_unmap_mem_op_data() - DMA-unmap the buffer attached to a 63 * memory operation 64 * @ctlr: the SPI controller requesting this dma_unmap() 65 * @op: the memory operation containing the buffer to unmap 66 * @sgt: a pointer to an sg_table previously initialized by 67 * spi_controller_dma_map_mem_op_data() 68 * 69 * Some controllers might want to do DMA on the data buffer embedded in @op. 70 * This helper prepares things so that the CPU can access the 71 * op->data.buf.{in,out} buffer again. 72 * 73 * This function is not intended to be called from SPI drivers. Only SPI 74 * controller drivers should use it. 75 * 76 * This function should be called after the DMA operation has finished and is 77 * only valid if the previous spi_controller_dma_map_mem_op_data() call 78 * returned 0. 79 * 80 * Return: 0 in case of success, a negative error code otherwise. 81 */ 82void spi_controller_dma_unmap_mem_op_data(struct spi_controller *ctlr, 83 const struct spi_mem_op *op, 84 struct sg_table *sgt) 85{ 86 struct device *dmadev; 87 88 if (!op->data.nbytes) 89 return; 90 91 if (op->data.dir == SPI_MEM_DATA_OUT && ctlr->dma_tx) 92 dmadev = ctlr->dma_tx->device->dev; 93 else if (op->data.dir == SPI_MEM_DATA_IN && ctlr->dma_rx) 94 dmadev = ctlr->dma_rx->device->dev; 95 else 96 dmadev = ctlr->dev.parent; 97 98 spi_unmap_buf(ctlr, dmadev, sgt, 99 op->data.dir == SPI_MEM_DATA_IN ? 100 DMA_FROM_DEVICE : DMA_TO_DEVICE); 101} 102EXPORT_SYMBOL_GPL(spi_controller_dma_unmap_mem_op_data); 103 104static int spi_check_buswidth_req(struct spi_mem *mem, u8 buswidth, bool tx) 105{ 106 u32 mode = mem->spi->mode; 107 108 switch (buswidth) { 109 case 1: 110 return 0; 111 112 case 2: 113 if ((tx && 114 (mode & (SPI_TX_DUAL | SPI_TX_QUAD | SPI_TX_OCTAL))) || 115 (!tx && 116 (mode & (SPI_RX_DUAL | SPI_RX_QUAD | SPI_RX_OCTAL)))) 117 return 0; 118 119 break; 120 121 case 4: 122 if ((tx && (mode & (SPI_TX_QUAD | SPI_TX_OCTAL))) || 123 (!tx && (mode & (SPI_RX_QUAD | SPI_RX_OCTAL)))) 124 return 0; 125 126 break; 127 128 case 8: 129 if ((tx && (mode & SPI_TX_OCTAL)) || 130 (!tx && (mode & SPI_RX_OCTAL))) 131 return 0; 132 133 break; 134 135 default: 136 break; 137 } 138 139 return -ENOTSUPP; 140} 141 142static bool spi_mem_check_buswidth(struct spi_mem *mem, 143 const struct spi_mem_op *op) 144{ 145 if (spi_check_buswidth_req(mem, op->cmd.buswidth, true)) 146 return false; 147 148 if (op->addr.nbytes && 149 spi_check_buswidth_req(mem, op->addr.buswidth, true)) 150 return false; 151 152 if (op->dummy.nbytes && 153 spi_check_buswidth_req(mem, op->dummy.buswidth, true)) 154 return false; 155 156 if (op->data.dir != SPI_MEM_NO_DATA && 157 spi_check_buswidth_req(mem, op->data.buswidth, 158 op->data.dir == SPI_MEM_DATA_OUT)) 159 return false; 160 161 return true; 162} 163 164bool spi_mem_default_supports_op(struct spi_mem *mem, 165 const struct spi_mem_op *op) 166{ 167 struct spi_controller *ctlr = mem->spi->controller; 168 bool op_is_dtr = 169 op->cmd.dtr || op->addr.dtr || op->dummy.dtr || op->data.dtr; 170 171 if (op_is_dtr) { 172 if (!spi_mem_controller_is_capable(ctlr, dtr)) 173 return false; 174 175 if (op->cmd.nbytes != 2) 176 return false; 177 } else { 178 if (op->cmd.nbytes != 1) 179 return false; 180 } 181 182 if (op->data.ecc) { 183 if (!spi_mem_controller_is_capable(ctlr, ecc)) 184 return false; 185 } 186 187 return spi_mem_check_buswidth(mem, op); 188} 189EXPORT_SYMBOL_GPL(spi_mem_default_supports_op); 190 191static bool spi_mem_buswidth_is_valid(u8 buswidth) 192{ 193 if (hweight8(buswidth) > 1 || buswidth > SPI_MEM_MAX_BUSWIDTH) 194 return false; 195 196 return true; 197} 198 199static int spi_mem_check_op(const struct spi_mem_op *op) 200{ 201 if (!op->cmd.buswidth || !op->cmd.nbytes) 202 return -EINVAL; 203 204 if ((op->addr.nbytes && !op->addr.buswidth) || 205 (op->dummy.nbytes && !op->dummy.buswidth) || 206 (op->data.nbytes && !op->data.buswidth)) 207 return -EINVAL; 208 209 if (!spi_mem_buswidth_is_valid(op->cmd.buswidth) || 210 !spi_mem_buswidth_is_valid(op->addr.buswidth) || 211 !spi_mem_buswidth_is_valid(op->dummy.buswidth) || 212 !spi_mem_buswidth_is_valid(op->data.buswidth)) 213 return -EINVAL; 214 215 /* Buffers must be DMA-able. */ 216 if (WARN_ON_ONCE(op->data.dir == SPI_MEM_DATA_IN && 217 object_is_on_stack(op->data.buf.in))) 218 return -EINVAL; 219 220 if (WARN_ON_ONCE(op->data.dir == SPI_MEM_DATA_OUT && 221 object_is_on_stack(op->data.buf.out))) 222 return -EINVAL; 223 224 return 0; 225} 226 227static bool spi_mem_internal_supports_op(struct spi_mem *mem, 228 const struct spi_mem_op *op) 229{ 230 struct spi_controller *ctlr = mem->spi->controller; 231 232 if (ctlr->mem_ops && ctlr->mem_ops->supports_op) 233 return ctlr->mem_ops->supports_op(mem, op); 234 235 return spi_mem_default_supports_op(mem, op); 236} 237 238/** 239 * spi_mem_supports_op() - Check if a memory device and the controller it is 240 * connected to support a specific memory operation 241 * @mem: the SPI memory 242 * @op: the memory operation to check 243 * 244 * Some controllers are only supporting Single or Dual IOs, others might only 245 * support specific opcodes, or it can even be that the controller and device 246 * both support Quad IOs but the hardware prevents you from using it because 247 * only 2 IO lines are connected. 248 * 249 * This function checks whether a specific operation is supported. 250 * 251 * Return: true if @op is supported, false otherwise. 252 */ 253bool spi_mem_supports_op(struct spi_mem *mem, const struct spi_mem_op *op) 254{ 255 if (spi_mem_check_op(op)) 256 return false; 257 258 return spi_mem_internal_supports_op(mem, op); 259} 260EXPORT_SYMBOL_GPL(spi_mem_supports_op); 261 262static int spi_mem_access_start(struct spi_mem *mem) 263{ 264 struct spi_controller *ctlr = mem->spi->controller; 265 266 /* 267 * Flush the message queue before executing our SPI memory 268 * operation to prevent preemption of regular SPI transfers. 269 */ 270 spi_flush_queue(ctlr); 271 272 if (ctlr->auto_runtime_pm) { 273 int ret; 274 275 ret = pm_runtime_resume_and_get(ctlr->dev.parent); 276 if (ret < 0) { 277 dev_err(&ctlr->dev, "Failed to power device: %d\n", 278 ret); 279 return ret; 280 } 281 } 282 283 mutex_lock(&ctlr->bus_lock_mutex); 284 mutex_lock(&ctlr->io_mutex); 285 286 return 0; 287} 288 289static void spi_mem_access_end(struct spi_mem *mem) 290{ 291 struct spi_controller *ctlr = mem->spi->controller; 292 293 mutex_unlock(&ctlr->io_mutex); 294 mutex_unlock(&ctlr->bus_lock_mutex); 295 296 if (ctlr->auto_runtime_pm) 297 pm_runtime_put(ctlr->dev.parent); 298} 299 300static void spi_mem_add_op_stats(struct spi_statistics __percpu *pcpu_stats, 301 const struct spi_mem_op *op, int exec_op_ret) 302{ 303 struct spi_statistics *stats; 304 u64 len, l2len; 305 306 get_cpu(); 307 stats = this_cpu_ptr(pcpu_stats); 308 u64_stats_update_begin(&stats->syncp); 309 310 /* 311 * We do not have the concept of messages or transfers. Let's consider 312 * that one operation is equivalent to one message and one transfer. 313 */ 314 u64_stats_inc(&stats->messages); 315 u64_stats_inc(&stats->transfers); 316 317 /* Use the sum of all lengths as bytes count and histogram value. */ 318 len = op->cmd.nbytes + op->addr.nbytes; 319 len += op->dummy.nbytes + op->data.nbytes; 320 u64_stats_add(&stats->bytes, len); 321 l2len = min(fls(len), SPI_STATISTICS_HISTO_SIZE) - 1; 322 u64_stats_inc(&stats->transfer_bytes_histo[l2len]); 323 324 /* Only account for data bytes as transferred bytes. */ 325 if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_OUT) 326 u64_stats_add(&stats->bytes_tx, op->data.nbytes); 327 if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_IN) 328 u64_stats_add(&stats->bytes_rx, op->data.nbytes); 329 330 /* 331 * A timeout is not an error, following the same behavior as 332 * spi_transfer_one_message(). 333 */ 334 if (exec_op_ret == -ETIMEDOUT) 335 u64_stats_inc(&stats->timedout); 336 else if (exec_op_ret) 337 u64_stats_inc(&stats->errors); 338 339 u64_stats_update_end(&stats->syncp); 340 put_cpu(); 341} 342 343/** 344 * spi_mem_exec_op() - Execute a memory operation 345 * @mem: the SPI memory 346 * @op: the memory operation to execute 347 * 348 * Executes a memory operation. 349 * 350 * This function first checks that @op is supported and then tries to execute 351 * it. 352 * 353 * Return: 0 in case of success, a negative error code otherwise. 354 */ 355int spi_mem_exec_op(struct spi_mem *mem, const struct spi_mem_op *op) 356{ 357 unsigned int tmpbufsize, xferpos = 0, totalxferlen = 0; 358 struct spi_controller *ctlr = mem->spi->controller; 359 struct spi_transfer xfers[4] = { }; 360 struct spi_message msg; 361 u8 *tmpbuf; 362 int ret; 363 364 ret = spi_mem_check_op(op); 365 if (ret) 366 return ret; 367 368 if (!spi_mem_internal_supports_op(mem, op)) 369 return -EOPNOTSUPP; 370 371 if (ctlr->mem_ops && ctlr->mem_ops->exec_op && !spi_get_csgpiod(mem->spi, 0)) { 372 ret = spi_mem_access_start(mem); 373 if (ret) 374 return ret; 375 376 ret = ctlr->mem_ops->exec_op(mem, op); 377 378 spi_mem_access_end(mem); 379 380 /* 381 * Some controllers only optimize specific paths (typically the 382 * read path) and expect the core to use the regular SPI 383 * interface in other cases. 384 */ 385 if (!ret || (ret != -ENOTSUPP && ret != -EOPNOTSUPP)) { 386 spi_mem_add_op_stats(ctlr->pcpu_statistics, op, ret); 387 spi_mem_add_op_stats(mem->spi->pcpu_statistics, op, ret); 388 389 return ret; 390 } 391 } 392 393 tmpbufsize = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes; 394 395 /* 396 * Allocate a buffer to transmit the CMD, ADDR cycles with kmalloc() so 397 * we're guaranteed that this buffer is DMA-able, as required by the 398 * SPI layer. 399 */ 400 tmpbuf = kzalloc(tmpbufsize, GFP_KERNEL | GFP_DMA); 401 if (!tmpbuf) 402 return -ENOMEM; 403 404 spi_message_init(&msg); 405 406 tmpbuf[0] = op->cmd.opcode; 407 xfers[xferpos].tx_buf = tmpbuf; 408 xfers[xferpos].len = op->cmd.nbytes; 409 xfers[xferpos].tx_nbits = op->cmd.buswidth; 410 spi_message_add_tail(&xfers[xferpos], &msg); 411 xferpos++; 412 totalxferlen++; 413 414 if (op->addr.nbytes) { 415 int i; 416 417 for (i = 0; i < op->addr.nbytes; i++) 418 tmpbuf[i + 1] = op->addr.val >> 419 (8 * (op->addr.nbytes - i - 1)); 420 421 xfers[xferpos].tx_buf = tmpbuf + 1; 422 xfers[xferpos].len = op->addr.nbytes; 423 xfers[xferpos].tx_nbits = op->addr.buswidth; 424 spi_message_add_tail(&xfers[xferpos], &msg); 425 xferpos++; 426 totalxferlen += op->addr.nbytes; 427 } 428 429 if (op->dummy.nbytes) { 430 memset(tmpbuf + op->addr.nbytes + 1, 0xff, op->dummy.nbytes); 431 xfers[xferpos].tx_buf = tmpbuf + op->addr.nbytes + 1; 432 xfers[xferpos].len = op->dummy.nbytes; 433 xfers[xferpos].tx_nbits = op->dummy.buswidth; 434 xfers[xferpos].dummy_data = 1; 435 spi_message_add_tail(&xfers[xferpos], &msg); 436 xferpos++; 437 totalxferlen += op->dummy.nbytes; 438 } 439 440 if (op->data.nbytes) { 441 if (op->data.dir == SPI_MEM_DATA_IN) { 442 xfers[xferpos].rx_buf = op->data.buf.in; 443 xfers[xferpos].rx_nbits = op->data.buswidth; 444 } else { 445 xfers[xferpos].tx_buf = op->data.buf.out; 446 xfers[xferpos].tx_nbits = op->data.buswidth; 447 } 448 449 xfers[xferpos].len = op->data.nbytes; 450 spi_message_add_tail(&xfers[xferpos], &msg); 451 xferpos++; 452 totalxferlen += op->data.nbytes; 453 } 454 455 ret = spi_sync(mem->spi, &msg); 456 457 kfree(tmpbuf); 458 459 if (ret) 460 return ret; 461 462 if (msg.actual_length != totalxferlen) 463 return -EIO; 464 465 return 0; 466} 467EXPORT_SYMBOL_GPL(spi_mem_exec_op); 468 469/** 470 * spi_mem_get_name() - Return the SPI mem device name to be used by the 471 * upper layer if necessary 472 * @mem: the SPI memory 473 * 474 * This function allows SPI mem users to retrieve the SPI mem device name. 475 * It is useful if the upper layer needs to expose a custom name for 476 * compatibility reasons. 477 * 478 * Return: a string containing the name of the memory device to be used 479 * by the SPI mem user 480 */ 481const char *spi_mem_get_name(struct spi_mem *mem) 482{ 483 return mem->name; 484} 485EXPORT_SYMBOL_GPL(spi_mem_get_name); 486 487/** 488 * spi_mem_adjust_op_size() - Adjust the data size of a SPI mem operation to 489 * match controller limitations 490 * @mem: the SPI memory 491 * @op: the operation to adjust 492 * 493 * Some controllers have FIFO limitations and must split a data transfer 494 * operation into multiple ones, others require a specific alignment for 495 * optimized accesses. This function allows SPI mem drivers to split a single 496 * operation into multiple sub-operations when required. 497 * 498 * Return: a negative error code if the controller can't properly adjust @op, 499 * 0 otherwise. Note that @op->data.nbytes will be updated if @op 500 * can't be handled in a single step. 501 */ 502int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op) 503{ 504 struct spi_controller *ctlr = mem->spi->controller; 505 size_t len; 506 507 if (ctlr->mem_ops && ctlr->mem_ops->adjust_op_size) 508 return ctlr->mem_ops->adjust_op_size(mem, op); 509 510 if (!ctlr->mem_ops || !ctlr->mem_ops->exec_op) { 511 len = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes; 512 513 if (len > spi_max_transfer_size(mem->spi)) 514 return -EINVAL; 515 516 op->data.nbytes = min3((size_t)op->data.nbytes, 517 spi_max_transfer_size(mem->spi), 518 spi_max_message_size(mem->spi) - 519 len); 520 if (!op->data.nbytes) 521 return -EINVAL; 522 } 523 524 return 0; 525} 526EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size); 527 528static ssize_t spi_mem_no_dirmap_read(struct spi_mem_dirmap_desc *desc, 529 u64 offs, size_t len, void *buf) 530{ 531 struct spi_mem_op op = desc->info.op_tmpl; 532 int ret; 533 534 op.addr.val = desc->info.offset + offs; 535 op.data.buf.in = buf; 536 op.data.nbytes = len; 537 ret = spi_mem_adjust_op_size(desc->mem, &op); 538 if (ret) 539 return ret; 540 541 ret = spi_mem_exec_op(desc->mem, &op); 542 if (ret) 543 return ret; 544 545 return op.data.nbytes; 546} 547 548static ssize_t spi_mem_no_dirmap_write(struct spi_mem_dirmap_desc *desc, 549 u64 offs, size_t len, const void *buf) 550{ 551 struct spi_mem_op op = desc->info.op_tmpl; 552 int ret; 553 554 op.addr.val = desc->info.offset + offs; 555 op.data.buf.out = buf; 556 op.data.nbytes = len; 557 ret = spi_mem_adjust_op_size(desc->mem, &op); 558 if (ret) 559 return ret; 560 561 ret = spi_mem_exec_op(desc->mem, &op); 562 if (ret) 563 return ret; 564 565 return op.data.nbytes; 566} 567 568/** 569 * spi_mem_dirmap_create() - Create a direct mapping descriptor 570 * @mem: SPI mem device this direct mapping should be created for 571 * @info: direct mapping information 572 * 573 * This function is creating a direct mapping descriptor which can then be used 574 * to access the memory using spi_mem_dirmap_read() or spi_mem_dirmap_write(). 575 * If the SPI controller driver does not support direct mapping, this function 576 * falls back to an implementation using spi_mem_exec_op(), so that the caller 577 * doesn't have to bother implementing a fallback on his own. 578 * 579 * Return: a valid pointer in case of success, and ERR_PTR() otherwise. 580 */ 581struct spi_mem_dirmap_desc * 582spi_mem_dirmap_create(struct spi_mem *mem, 583 const struct spi_mem_dirmap_info *info) 584{ 585 struct spi_controller *ctlr = mem->spi->controller; 586 struct spi_mem_dirmap_desc *desc; 587 int ret = -ENOTSUPP; 588 589 /* Make sure the number of address cycles is between 1 and 8 bytes. */ 590 if (!info->op_tmpl.addr.nbytes || info->op_tmpl.addr.nbytes > 8) 591 return ERR_PTR(-EINVAL); 592 593 /* data.dir should either be SPI_MEM_DATA_IN or SPI_MEM_DATA_OUT. */ 594 if (info->op_tmpl.data.dir == SPI_MEM_NO_DATA) 595 return ERR_PTR(-EINVAL); 596 597 desc = kzalloc(sizeof(*desc), GFP_KERNEL); 598 if (!desc) 599 return ERR_PTR(-ENOMEM); 600 601 desc->mem = mem; 602 desc->info = *info; 603 if (ctlr->mem_ops && ctlr->mem_ops->dirmap_create) 604 ret = ctlr->mem_ops->dirmap_create(desc); 605 606 if (ret) { 607 desc->nodirmap = true; 608 if (!spi_mem_supports_op(desc->mem, &desc->info.op_tmpl)) 609 ret = -EOPNOTSUPP; 610 else 611 ret = 0; 612 } 613 614 if (ret) { 615 kfree(desc); 616 return ERR_PTR(ret); 617 } 618 619 return desc; 620} 621EXPORT_SYMBOL_GPL(spi_mem_dirmap_create); 622 623/** 624 * spi_mem_dirmap_destroy() - Destroy a direct mapping descriptor 625 * @desc: the direct mapping descriptor to destroy 626 * 627 * This function destroys a direct mapping descriptor previously created by 628 * spi_mem_dirmap_create(). 629 */ 630void spi_mem_dirmap_destroy(struct spi_mem_dirmap_desc *desc) 631{ 632 struct spi_controller *ctlr = desc->mem->spi->controller; 633 634 if (!desc->nodirmap && ctlr->mem_ops && ctlr->mem_ops->dirmap_destroy) 635 ctlr->mem_ops->dirmap_destroy(desc); 636 637 kfree(desc); 638} 639EXPORT_SYMBOL_GPL(spi_mem_dirmap_destroy); 640 641static void devm_spi_mem_dirmap_release(struct device *dev, void *res) 642{ 643 struct spi_mem_dirmap_desc *desc = *(struct spi_mem_dirmap_desc **)res; 644 645 spi_mem_dirmap_destroy(desc); 646} 647 648/** 649 * devm_spi_mem_dirmap_create() - Create a direct mapping descriptor and attach 650 * it to a device 651 * @dev: device the dirmap desc will be attached to 652 * @mem: SPI mem device this direct mapping should be created for 653 * @info: direct mapping information 654 * 655 * devm_ variant of the spi_mem_dirmap_create() function. See 656 * spi_mem_dirmap_create() for more details. 657 * 658 * Return: a valid pointer in case of success, and ERR_PTR() otherwise. 659 */ 660struct spi_mem_dirmap_desc * 661devm_spi_mem_dirmap_create(struct device *dev, struct spi_mem *mem, 662 const struct spi_mem_dirmap_info *info) 663{ 664 struct spi_mem_dirmap_desc **ptr, *desc; 665 666 ptr = devres_alloc(devm_spi_mem_dirmap_release, sizeof(*ptr), 667 GFP_KERNEL); 668 if (!ptr) 669 return ERR_PTR(-ENOMEM); 670 671 desc = spi_mem_dirmap_create(mem, info); 672 if (IS_ERR(desc)) { 673 devres_free(ptr); 674 } else { 675 *ptr = desc; 676 devres_add(dev, ptr); 677 } 678 679 return desc; 680} 681EXPORT_SYMBOL_GPL(devm_spi_mem_dirmap_create); 682 683static int devm_spi_mem_dirmap_match(struct device *dev, void *res, void *data) 684{ 685 struct spi_mem_dirmap_desc **ptr = res; 686 687 if (WARN_ON(!ptr || !*ptr)) 688 return 0; 689 690 return *ptr == data; 691} 692 693/** 694 * devm_spi_mem_dirmap_destroy() - Destroy a direct mapping descriptor attached 695 * to a device 696 * @dev: device the dirmap desc is attached to 697 * @desc: the direct mapping descriptor to destroy 698 * 699 * devm_ variant of the spi_mem_dirmap_destroy() function. See 700 * spi_mem_dirmap_destroy() for more details. 701 */ 702void devm_spi_mem_dirmap_destroy(struct device *dev, 703 struct spi_mem_dirmap_desc *desc) 704{ 705 devres_release(dev, devm_spi_mem_dirmap_release, 706 devm_spi_mem_dirmap_match, desc); 707} 708EXPORT_SYMBOL_GPL(devm_spi_mem_dirmap_destroy); 709 710/** 711 * spi_mem_dirmap_read() - Read data through a direct mapping 712 * @desc: direct mapping descriptor 713 * @offs: offset to start reading from. Note that this is not an absolute 714 * offset, but the offset within the direct mapping which already has 715 * its own offset 716 * @len: length in bytes 717 * @buf: destination buffer. This buffer must be DMA-able 718 * 719 * This function reads data from a memory device using a direct mapping 720 * previously instantiated with spi_mem_dirmap_create(). 721 * 722 * Return: the amount of data read from the memory device or a negative error 723 * code. Note that the returned size might be smaller than @len, and the caller 724 * is responsible for calling spi_mem_dirmap_read() again when that happens. 725 */ 726ssize_t spi_mem_dirmap_read(struct spi_mem_dirmap_desc *desc, 727 u64 offs, size_t len, void *buf) 728{ 729 struct spi_controller *ctlr = desc->mem->spi->controller; 730 ssize_t ret; 731 732 if (desc->info.op_tmpl.data.dir != SPI_MEM_DATA_IN) 733 return -EINVAL; 734 735 if (!len) 736 return 0; 737 738 if (desc->nodirmap) { 739 ret = spi_mem_no_dirmap_read(desc, offs, len, buf); 740 } else if (ctlr->mem_ops && ctlr->mem_ops->dirmap_read) { 741 ret = spi_mem_access_start(desc->mem); 742 if (ret) 743 return ret; 744 745 ret = ctlr->mem_ops->dirmap_read(desc, offs, len, buf); 746 747 spi_mem_access_end(desc->mem); 748 } else { 749 ret = -ENOTSUPP; 750 } 751 752 return ret; 753} 754EXPORT_SYMBOL_GPL(spi_mem_dirmap_read); 755 756/** 757 * spi_mem_dirmap_write() - Write data through a direct mapping 758 * @desc: direct mapping descriptor 759 * @offs: offset to start writing from. Note that this is not an absolute 760 * offset, but the offset within the direct mapping which already has 761 * its own offset 762 * @len: length in bytes 763 * @buf: source buffer. This buffer must be DMA-able 764 * 765 * This function writes data to a memory device using a direct mapping 766 * previously instantiated with spi_mem_dirmap_create(). 767 * 768 * Return: the amount of data written to the memory device or a negative error 769 * code. Note that the returned size might be smaller than @len, and the caller 770 * is responsible for calling spi_mem_dirmap_write() again when that happens. 771 */ 772ssize_t spi_mem_dirmap_write(struct spi_mem_dirmap_desc *desc, 773 u64 offs, size_t len, const void *buf) 774{ 775 struct spi_controller *ctlr = desc->mem->spi->controller; 776 ssize_t ret; 777 778 if (desc->info.op_tmpl.data.dir != SPI_MEM_DATA_OUT) 779 return -EINVAL; 780 781 if (!len) 782 return 0; 783 784 if (desc->nodirmap) { 785 ret = spi_mem_no_dirmap_write(desc, offs, len, buf); 786 } else if (ctlr->mem_ops && ctlr->mem_ops->dirmap_write) { 787 ret = spi_mem_access_start(desc->mem); 788 if (ret) 789 return ret; 790 791 ret = ctlr->mem_ops->dirmap_write(desc, offs, len, buf); 792 793 spi_mem_access_end(desc->mem); 794 } else { 795 ret = -ENOTSUPP; 796 } 797 798 return ret; 799} 800EXPORT_SYMBOL_GPL(spi_mem_dirmap_write); 801 802static inline struct spi_mem_driver *to_spi_mem_drv(struct device_driver *drv) 803{ 804 return container_of(drv, struct spi_mem_driver, spidrv.driver); 805} 806 807static int spi_mem_read_status(struct spi_mem *mem, 808 const struct spi_mem_op *op, 809 u16 *status) 810{ 811 const u8 *bytes = (u8 *)op->data.buf.in; 812 int ret; 813 814 ret = spi_mem_exec_op(mem, op); 815 if (ret) 816 return ret; 817 818 if (op->data.nbytes > 1) 819 *status = ((u16)bytes[0] << 8) | bytes[1]; 820 else 821 *status = bytes[0]; 822 823 return 0; 824} 825 826/** 827 * spi_mem_poll_status() - Poll memory device status 828 * @mem: SPI memory device 829 * @op: the memory operation to execute 830 * @mask: status bitmask to ckeck 831 * @match: (status & mask) expected value 832 * @initial_delay_us: delay in us before starting to poll 833 * @polling_delay_us: time to sleep between reads in us 834 * @timeout_ms: timeout in milliseconds 835 * 836 * This function polls a status register and returns when 837 * (status & mask) == match or when the timeout has expired. 838 * 839 * Return: 0 in case of success, -ETIMEDOUT in case of error, 840 * -EOPNOTSUPP if not supported. 841 */ 842int spi_mem_poll_status(struct spi_mem *mem, 843 const struct spi_mem_op *op, 844 u16 mask, u16 match, 845 unsigned long initial_delay_us, 846 unsigned long polling_delay_us, 847 u16 timeout_ms) 848{ 849 struct spi_controller *ctlr = mem->spi->controller; 850 int ret = -EOPNOTSUPP; 851 int read_status_ret; 852 u16 status; 853 854 if (op->data.nbytes < 1 || op->data.nbytes > 2 || 855 op->data.dir != SPI_MEM_DATA_IN) 856 return -EINVAL; 857 858 if (ctlr->mem_ops && ctlr->mem_ops->poll_status && !spi_get_csgpiod(mem->spi, 0)) { 859 ret = spi_mem_access_start(mem); 860 if (ret) 861 return ret; 862 863 ret = ctlr->mem_ops->poll_status(mem, op, mask, match, 864 initial_delay_us, polling_delay_us, 865 timeout_ms); 866 867 spi_mem_access_end(mem); 868 } 869 870 if (ret == -EOPNOTSUPP) { 871 if (!spi_mem_supports_op(mem, op)) 872 return ret; 873 874 if (initial_delay_us < 10) 875 udelay(initial_delay_us); 876 else 877 usleep_range((initial_delay_us >> 2) + 1, 878 initial_delay_us); 879 880 ret = read_poll_timeout(spi_mem_read_status, read_status_ret, 881 (read_status_ret || ((status) & mask) == match), 882 polling_delay_us, timeout_ms * 1000, false, mem, 883 op, &status); 884 if (read_status_ret) 885 return read_status_ret; 886 } 887 888 return ret; 889} 890EXPORT_SYMBOL_GPL(spi_mem_poll_status); 891 892static int spi_mem_probe(struct spi_device *spi) 893{ 894 struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver); 895 struct spi_controller *ctlr = spi->controller; 896 struct spi_mem *mem; 897 898 mem = devm_kzalloc(&spi->dev, sizeof(*mem), GFP_KERNEL); 899 if (!mem) 900 return -ENOMEM; 901 902 mem->spi = spi; 903 904 if (ctlr->mem_ops && ctlr->mem_ops->get_name) 905 mem->name = ctlr->mem_ops->get_name(mem); 906 else 907 mem->name = dev_name(&spi->dev); 908 909 if (IS_ERR_OR_NULL(mem->name)) 910 return PTR_ERR_OR_ZERO(mem->name); 911 912 spi_set_drvdata(spi, mem); 913 914 return memdrv->probe(mem); 915} 916 917static void spi_mem_remove(struct spi_device *spi) 918{ 919 struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver); 920 struct spi_mem *mem = spi_get_drvdata(spi); 921 922 if (memdrv->remove) 923 memdrv->remove(mem); 924} 925 926static void spi_mem_shutdown(struct spi_device *spi) 927{ 928 struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver); 929 struct spi_mem *mem = spi_get_drvdata(spi); 930 931 if (memdrv->shutdown) 932 memdrv->shutdown(mem); 933} 934 935/** 936 * spi_mem_driver_register_with_owner() - Register a SPI memory driver 937 * @memdrv: the SPI memory driver to register 938 * @owner: the owner of this driver 939 * 940 * Registers a SPI memory driver. 941 * 942 * Return: 0 in case of success, a negative error core otherwise. 943 */ 944 945int spi_mem_driver_register_with_owner(struct spi_mem_driver *memdrv, 946 struct module *owner) 947{ 948 memdrv->spidrv.probe = spi_mem_probe; 949 memdrv->spidrv.remove = spi_mem_remove; 950 memdrv->spidrv.shutdown = spi_mem_shutdown; 951 952 return __spi_register_driver(owner, &memdrv->spidrv); 953} 954EXPORT_SYMBOL_GPL(spi_mem_driver_register_with_owner); 955 956/** 957 * spi_mem_driver_unregister() - Unregister a SPI memory driver 958 * @memdrv: the SPI memory driver to unregister 959 * 960 * Unregisters a SPI memory driver. 961 */ 962void spi_mem_driver_unregister(struct spi_mem_driver *memdrv) 963{ 964 spi_unregister_driver(&memdrv->spidrv); 965} 966EXPORT_SYMBOL_GPL(spi_mem_driver_unregister); 967