1 /* 2 * SH RSPI driver 3 * 4 * Copyright (C) 2012 Renesas Solutions Corp. 5 * 6 * Based on spi-sh.c: 7 * Copyright (C) 2011 Renesas Solutions Corp. 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; version 2 of the License. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 21 * 22 */ 23 24 #include <linux/module.h> 25 #include <linux/kernel.h> 26 #include <linux/sched.h> 27 #include <linux/errno.h> 28 #include <linux/list.h> 29 #include <linux/workqueue.h> 30 #include <linux/interrupt.h> 31 #include <linux/platform_device.h> 32 #include <linux/io.h> 33 #include <linux/clk.h> 34 #include <linux/dmaengine.h> 35 #include <linux/dma-mapping.h> 36 #include <linux/sh_dma.h> 37 #include <linux/spi/spi.h> 38 #include <linux/spi/rspi.h> 39 40 #define RSPI_SPCR 0x00 41 #define RSPI_SSLP 0x01 42 #define RSPI_SPPCR 0x02 43 #define RSPI_SPSR 0x03 44 #define RSPI_SPDR 0x04 45 #define RSPI_SPSCR 0x08 46 #define RSPI_SPSSR 0x09 47 #define RSPI_SPBR 0x0a 48 #define RSPI_SPDCR 0x0b 49 #define RSPI_SPCKD 0x0c 50 #define RSPI_SSLND 0x0d 51 #define RSPI_SPND 0x0e 52 #define RSPI_SPCR2 0x0f 53 #define RSPI_SPCMD0 0x10 54 #define RSPI_SPCMD1 0x12 55 #define RSPI_SPCMD2 0x14 56 #define RSPI_SPCMD3 0x16 57 #define RSPI_SPCMD4 0x18 58 #define RSPI_SPCMD5 0x1a 59 #define RSPI_SPCMD6 0x1c 60 #define RSPI_SPCMD7 0x1e 61 62 /* SPCR */ 63 #define SPCR_SPRIE 0x80 64 #define SPCR_SPE 0x40 65 #define SPCR_SPTIE 0x20 66 #define SPCR_SPEIE 0x10 67 #define SPCR_MSTR 0x08 68 #define SPCR_MODFEN 0x04 69 #define SPCR_TXMD 0x02 70 #define SPCR_SPMS 0x01 71 72 /* SSLP */ 73 #define SSLP_SSL1P 0x02 74 #define SSLP_SSL0P 0x01 75 76 /* SPPCR */ 77 #define SPPCR_MOIFE 0x20 78 #define SPPCR_MOIFV 0x10 79 #define SPPCR_SPOM 0x04 80 #define SPPCR_SPLP2 0x02 81 #define SPPCR_SPLP 0x01 82 83 /* SPSR */ 84 #define SPSR_SPRF 0x80 85 #define SPSR_SPTEF 0x20 86 #define SPSR_PERF 0x08 87 #define SPSR_MODF 0x04 88 #define SPSR_IDLNF 0x02 89 #define SPSR_OVRF 0x01 90 91 /* SPSCR */ 92 #define SPSCR_SPSLN_MASK 0x07 93 94 /* SPSSR */ 95 #define SPSSR_SPECM_MASK 0x70 96 #define SPSSR_SPCP_MASK 0x07 97 98 /* SPDCR */ 99 #define SPDCR_SPLW 0x20 100 #define SPDCR_SPRDTD 0x10 101 #define SPDCR_SLSEL1 0x08 102 #define SPDCR_SLSEL0 0x04 103 #define SPDCR_SLSEL_MASK 0x0c 104 #define SPDCR_SPFC1 0x02 105 #define SPDCR_SPFC0 0x01 106 107 /* SPCKD */ 108 #define SPCKD_SCKDL_MASK 0x07 109 110 /* SSLND */ 111 #define SSLND_SLNDL_MASK 0x07 112 113 /* SPND */ 114 #define SPND_SPNDL_MASK 0x07 115 116 /* SPCR2 */ 117 #define SPCR2_PTE 0x08 118 #define SPCR2_SPIE 0x04 119 #define SPCR2_SPOE 0x02 120 #define SPCR2_SPPE 0x01 121 122 /* SPCMDn */ 123 #define SPCMD_SCKDEN 0x8000 124 #define SPCMD_SLNDEN 0x4000 125 #define SPCMD_SPNDEN 0x2000 126 #define SPCMD_LSBF 0x1000 127 #define SPCMD_SPB_MASK 0x0f00 128 #define SPCMD_SPB_8_TO_16(bit) (((bit - 1) << 8) & SPCMD_SPB_MASK) 129 #define SPCMD_SPB_20BIT 0x0000 130 #define SPCMD_SPB_24BIT 0x0100 131 #define SPCMD_SPB_32BIT 0x0200 132 #define SPCMD_SSLKP 0x0080 133 #define SPCMD_SSLA_MASK 0x0030 134 #define SPCMD_BRDV_MASK 0x000c 135 #define SPCMD_CPOL 0x0002 136 #define SPCMD_CPHA 0x0001 137 138 struct rspi_data { 139 void __iomem *addr; 140 u32 max_speed_hz; 141 struct spi_master *master; 142 struct list_head queue; 143 struct work_struct ws; 144 wait_queue_head_t wait; 145 spinlock_t lock; 146 struct clk *clk; 147 unsigned char spsr; 148 149 /* for dmaengine */ 150 struct dma_chan *chan_tx; 151 struct dma_chan *chan_rx; 152 int irq; 153 154 unsigned dma_width_16bit:1; 155 unsigned dma_callbacked:1; 156 }; 157 158 static void rspi_write8(struct rspi_data *rspi, u8 data, u16 offset) 159 { 160 iowrite8(data, rspi->addr + offset); 161 } 162 163 static void rspi_write16(struct rspi_data *rspi, u16 data, u16 offset) 164 { 165 iowrite16(data, rspi->addr + offset); 166 } 167 168 static u8 rspi_read8(struct rspi_data *rspi, u16 offset) 169 { 170 return ioread8(rspi->addr + offset); 171 } 172 173 static u16 rspi_read16(struct rspi_data *rspi, u16 offset) 174 { 175 return ioread16(rspi->addr + offset); 176 } 177 178 static unsigned char rspi_calc_spbr(struct rspi_data *rspi) 179 { 180 int tmp; 181 unsigned char spbr; 182 183 tmp = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz) - 1; 184 spbr = clamp(tmp, 0, 255); 185 186 return spbr; 187 } 188 189 static void rspi_enable_irq(struct rspi_data *rspi, u8 enable) 190 { 191 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR); 192 } 193 194 static void rspi_disable_irq(struct rspi_data *rspi, u8 disable) 195 { 196 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR); 197 } 198 199 static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask, 200 u8 enable_bit) 201 { 202 int ret; 203 204 rspi->spsr = rspi_read8(rspi, RSPI_SPSR); 205 rspi_enable_irq(rspi, enable_bit); 206 ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ); 207 if (ret == 0 && !(rspi->spsr & wait_mask)) 208 return -ETIMEDOUT; 209 210 return 0; 211 } 212 213 static void rspi_assert_ssl(struct rspi_data *rspi) 214 { 215 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR); 216 } 217 218 static void rspi_negate_ssl(struct rspi_data *rspi) 219 { 220 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR); 221 } 222 223 static int rspi_set_config_register(struct rspi_data *rspi, int access_size) 224 { 225 /* Sets output mode(CMOS) and MOSI signal(from previous transfer) */ 226 rspi_write8(rspi, 0x00, RSPI_SPPCR); 227 228 /* Sets transfer bit rate */ 229 rspi_write8(rspi, rspi_calc_spbr(rspi), RSPI_SPBR); 230 231 /* Sets number of frames to be used: 1 frame */ 232 rspi_write8(rspi, 0x00, RSPI_SPDCR); 233 234 /* Sets RSPCK, SSL, next-access delay value */ 235 rspi_write8(rspi, 0x00, RSPI_SPCKD); 236 rspi_write8(rspi, 0x00, RSPI_SSLND); 237 rspi_write8(rspi, 0x00, RSPI_SPND); 238 239 /* Sets parity, interrupt mask */ 240 rspi_write8(rspi, 0x00, RSPI_SPCR2); 241 242 /* Sets SPCMD */ 243 rspi_write16(rspi, SPCMD_SPB_8_TO_16(access_size) | SPCMD_SSLKP, 244 RSPI_SPCMD0); 245 246 /* Sets RSPI mode */ 247 rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR); 248 249 return 0; 250 } 251 252 static int rspi_send_pio(struct rspi_data *rspi, struct spi_message *mesg, 253 struct spi_transfer *t) 254 { 255 int remain = t->len; 256 u8 *data; 257 258 data = (u8 *)t->tx_buf; 259 while (remain > 0) { 260 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_TXMD, 261 RSPI_SPCR); 262 263 if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) { 264 dev_err(&rspi->master->dev, 265 "%s: tx empty timeout\n", __func__); 266 return -ETIMEDOUT; 267 } 268 269 rspi_write16(rspi, *data, RSPI_SPDR); 270 data++; 271 remain--; 272 } 273 274 /* Waiting for the last transmition */ 275 rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE); 276 277 return 0; 278 } 279 280 static void rspi_dma_complete(void *arg) 281 { 282 struct rspi_data *rspi = arg; 283 284 rspi->dma_callbacked = 1; 285 wake_up_interruptible(&rspi->wait); 286 } 287 288 static int rspi_dma_map_sg(struct scatterlist *sg, void *buf, unsigned len, 289 struct dma_chan *chan, 290 enum dma_transfer_direction dir) 291 { 292 sg_init_table(sg, 1); 293 sg_set_buf(sg, buf, len); 294 sg_dma_len(sg) = len; 295 return dma_map_sg(chan->device->dev, sg, 1, dir); 296 } 297 298 static void rspi_dma_unmap_sg(struct scatterlist *sg, struct dma_chan *chan, 299 enum dma_transfer_direction dir) 300 { 301 dma_unmap_sg(chan->device->dev, sg, 1, dir); 302 } 303 304 static void rspi_memory_to_8bit(void *buf, const void *data, unsigned len) 305 { 306 u16 *dst = buf; 307 const u8 *src = data; 308 309 while (len) { 310 *dst++ = (u16)(*src++); 311 len--; 312 } 313 } 314 315 static void rspi_memory_from_8bit(void *buf, const void *data, unsigned len) 316 { 317 u8 *dst = buf; 318 const u16 *src = data; 319 320 while (len) { 321 *dst++ = (u8)*src++; 322 len--; 323 } 324 } 325 326 static int rspi_send_dma(struct rspi_data *rspi, struct spi_transfer *t) 327 { 328 struct scatterlist sg; 329 void *buf = NULL; 330 struct dma_async_tx_descriptor *desc; 331 unsigned len; 332 int ret = 0; 333 334 if (rspi->dma_width_16bit) { 335 /* 336 * If DMAC bus width is 16-bit, the driver allocates a dummy 337 * buffer. And, the driver converts original data into the 338 * DMAC data as the following format: 339 * original data: 1st byte, 2nd byte ... 340 * DMAC data: 1st byte, dummy, 2nd byte, dummy ... 341 */ 342 len = t->len * 2; 343 buf = kmalloc(len, GFP_KERNEL); 344 if (!buf) 345 return -ENOMEM; 346 rspi_memory_to_8bit(buf, t->tx_buf, t->len); 347 } else { 348 len = t->len; 349 buf = (void *)t->tx_buf; 350 } 351 352 if (!rspi_dma_map_sg(&sg, buf, len, rspi->chan_tx, DMA_TO_DEVICE)) { 353 ret = -EFAULT; 354 goto end_nomap; 355 } 356 desc = dmaengine_prep_slave_sg(rspi->chan_tx, &sg, 1, DMA_TO_DEVICE, 357 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 358 if (!desc) { 359 ret = -EIO; 360 goto end; 361 } 362 363 /* 364 * DMAC needs SPTIE, but if SPTIE is set, this IRQ routine will be 365 * called. So, this driver disables the IRQ while DMA transfer. 366 */ 367 disable_irq(rspi->irq); 368 369 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_TXMD, RSPI_SPCR); 370 rspi_enable_irq(rspi, SPCR_SPTIE); 371 rspi->dma_callbacked = 0; 372 373 desc->callback = rspi_dma_complete; 374 desc->callback_param = rspi; 375 dmaengine_submit(desc); 376 dma_async_issue_pending(rspi->chan_tx); 377 378 ret = wait_event_interruptible_timeout(rspi->wait, 379 rspi->dma_callbacked, HZ); 380 if (ret > 0 && rspi->dma_callbacked) 381 ret = 0; 382 else if (!ret) 383 ret = -ETIMEDOUT; 384 rspi_disable_irq(rspi, SPCR_SPTIE); 385 386 enable_irq(rspi->irq); 387 388 end: 389 rspi_dma_unmap_sg(&sg, rspi->chan_tx, DMA_TO_DEVICE); 390 end_nomap: 391 if (rspi->dma_width_16bit) 392 kfree(buf); 393 394 return ret; 395 } 396 397 static void rspi_receive_init(struct rspi_data *rspi) 398 { 399 unsigned char spsr; 400 401 spsr = rspi_read8(rspi, RSPI_SPSR); 402 if (spsr & SPSR_SPRF) 403 rspi_read16(rspi, RSPI_SPDR); /* dummy read */ 404 if (spsr & SPSR_OVRF) 405 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF, 406 RSPI_SPCR); 407 } 408 409 static int rspi_receive_pio(struct rspi_data *rspi, struct spi_message *mesg, 410 struct spi_transfer *t) 411 { 412 int remain = t->len; 413 u8 *data; 414 415 rspi_receive_init(rspi); 416 417 data = (u8 *)t->rx_buf; 418 while (remain > 0) { 419 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_TXMD, 420 RSPI_SPCR); 421 422 if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) { 423 dev_err(&rspi->master->dev, 424 "%s: tx empty timeout\n", __func__); 425 return -ETIMEDOUT; 426 } 427 /* dummy write for generate clock */ 428 rspi_write16(rspi, 0x00, RSPI_SPDR); 429 430 if (rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE) < 0) { 431 dev_err(&rspi->master->dev, 432 "%s: receive timeout\n", __func__); 433 return -ETIMEDOUT; 434 } 435 /* SPDR allows 16 or 32-bit access only */ 436 *data = (u8)rspi_read16(rspi, RSPI_SPDR); 437 438 data++; 439 remain--; 440 } 441 442 return 0; 443 } 444 445 static int rspi_receive_dma(struct rspi_data *rspi, struct spi_transfer *t) 446 { 447 struct scatterlist sg, sg_dummy; 448 void *dummy = NULL, *rx_buf = NULL; 449 struct dma_async_tx_descriptor *desc, *desc_dummy; 450 unsigned len; 451 int ret = 0; 452 453 if (rspi->dma_width_16bit) { 454 /* 455 * If DMAC bus width is 16-bit, the driver allocates a dummy 456 * buffer. And, finally the driver converts the DMAC data into 457 * actual data as the following format: 458 * DMAC data: 1st byte, dummy, 2nd byte, dummy ... 459 * actual data: 1st byte, 2nd byte ... 460 */ 461 len = t->len * 2; 462 rx_buf = kmalloc(len, GFP_KERNEL); 463 if (!rx_buf) 464 return -ENOMEM; 465 } else { 466 len = t->len; 467 rx_buf = t->rx_buf; 468 } 469 470 /* prepare dummy transfer to generate SPI clocks */ 471 dummy = kzalloc(len, GFP_KERNEL); 472 if (!dummy) { 473 ret = -ENOMEM; 474 goto end_nomap; 475 } 476 if (!rspi_dma_map_sg(&sg_dummy, dummy, len, rspi->chan_tx, 477 DMA_TO_DEVICE)) { 478 ret = -EFAULT; 479 goto end_nomap; 480 } 481 desc_dummy = dmaengine_prep_slave_sg(rspi->chan_tx, &sg_dummy, 1, 482 DMA_TO_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 483 if (!desc_dummy) { 484 ret = -EIO; 485 goto end_dummy_mapped; 486 } 487 488 /* prepare receive transfer */ 489 if (!rspi_dma_map_sg(&sg, rx_buf, len, rspi->chan_rx, 490 DMA_FROM_DEVICE)) { 491 ret = -EFAULT; 492 goto end_dummy_mapped; 493 494 } 495 desc = dmaengine_prep_slave_sg(rspi->chan_rx, &sg, 1, DMA_FROM_DEVICE, 496 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 497 if (!desc) { 498 ret = -EIO; 499 goto end; 500 } 501 502 rspi_receive_init(rspi); 503 504 /* 505 * DMAC needs SPTIE, but if SPTIE is set, this IRQ routine will be 506 * called. So, this driver disables the IRQ while DMA transfer. 507 */ 508 disable_irq(rspi->irq); 509 510 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_TXMD, RSPI_SPCR); 511 rspi_enable_irq(rspi, SPCR_SPTIE | SPCR_SPRIE); 512 rspi->dma_callbacked = 0; 513 514 desc->callback = rspi_dma_complete; 515 desc->callback_param = rspi; 516 dmaengine_submit(desc); 517 dma_async_issue_pending(rspi->chan_rx); 518 519 desc_dummy->callback = NULL; /* No callback */ 520 dmaengine_submit(desc_dummy); 521 dma_async_issue_pending(rspi->chan_tx); 522 523 ret = wait_event_interruptible_timeout(rspi->wait, 524 rspi->dma_callbacked, HZ); 525 if (ret > 0 && rspi->dma_callbacked) 526 ret = 0; 527 else if (!ret) 528 ret = -ETIMEDOUT; 529 rspi_disable_irq(rspi, SPCR_SPTIE | SPCR_SPRIE); 530 531 enable_irq(rspi->irq); 532 533 end: 534 rspi_dma_unmap_sg(&sg, rspi->chan_rx, DMA_FROM_DEVICE); 535 end_dummy_mapped: 536 rspi_dma_unmap_sg(&sg_dummy, rspi->chan_tx, DMA_TO_DEVICE); 537 end_nomap: 538 if (rspi->dma_width_16bit) { 539 if (!ret) 540 rspi_memory_from_8bit(t->rx_buf, rx_buf, t->len); 541 kfree(rx_buf); 542 } 543 kfree(dummy); 544 545 return ret; 546 } 547 548 static int rspi_is_dma(struct rspi_data *rspi, struct spi_transfer *t) 549 { 550 if (t->tx_buf && rspi->chan_tx) 551 return 1; 552 /* If the module receives data by DMAC, it also needs TX DMAC */ 553 if (t->rx_buf && rspi->chan_tx && rspi->chan_rx) 554 return 1; 555 556 return 0; 557 } 558 559 static void rspi_work(struct work_struct *work) 560 { 561 struct rspi_data *rspi = container_of(work, struct rspi_data, ws); 562 struct spi_message *mesg; 563 struct spi_transfer *t; 564 unsigned long flags; 565 int ret; 566 567 while (1) { 568 spin_lock_irqsave(&rspi->lock, flags); 569 if (list_empty(&rspi->queue)) { 570 spin_unlock_irqrestore(&rspi->lock, flags); 571 break; 572 } 573 mesg = list_entry(rspi->queue.next, struct spi_message, queue); 574 list_del_init(&mesg->queue); 575 spin_unlock_irqrestore(&rspi->lock, flags); 576 577 rspi_assert_ssl(rspi); 578 579 list_for_each_entry(t, &mesg->transfers, transfer_list) { 580 if (t->tx_buf) { 581 if (rspi_is_dma(rspi, t)) 582 ret = rspi_send_dma(rspi, t); 583 else 584 ret = rspi_send_pio(rspi, mesg, t); 585 if (ret < 0) 586 goto error; 587 } 588 if (t->rx_buf) { 589 if (rspi_is_dma(rspi, t)) 590 ret = rspi_receive_dma(rspi, t); 591 else 592 ret = rspi_receive_pio(rspi, mesg, t); 593 if (ret < 0) 594 goto error; 595 } 596 mesg->actual_length += t->len; 597 } 598 rspi_negate_ssl(rspi); 599 600 mesg->status = 0; 601 mesg->complete(mesg->context); 602 } 603 604 return; 605 606 error: 607 mesg->status = ret; 608 mesg->complete(mesg->context); 609 } 610 611 static int rspi_setup(struct spi_device *spi) 612 { 613 struct rspi_data *rspi = spi_master_get_devdata(spi->master); 614 615 if (!spi->bits_per_word) 616 spi->bits_per_word = 8; 617 rspi->max_speed_hz = spi->max_speed_hz; 618 619 rspi_set_config_register(rspi, 8); 620 621 return 0; 622 } 623 624 static int rspi_transfer(struct spi_device *spi, struct spi_message *mesg) 625 { 626 struct rspi_data *rspi = spi_master_get_devdata(spi->master); 627 unsigned long flags; 628 629 mesg->actual_length = 0; 630 mesg->status = -EINPROGRESS; 631 632 spin_lock_irqsave(&rspi->lock, flags); 633 list_add_tail(&mesg->queue, &rspi->queue); 634 schedule_work(&rspi->ws); 635 spin_unlock_irqrestore(&rspi->lock, flags); 636 637 return 0; 638 } 639 640 static void rspi_cleanup(struct spi_device *spi) 641 { 642 } 643 644 static irqreturn_t rspi_irq(int irq, void *_sr) 645 { 646 struct rspi_data *rspi = (struct rspi_data *)_sr; 647 unsigned long spsr; 648 irqreturn_t ret = IRQ_NONE; 649 unsigned char disable_irq = 0; 650 651 rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR); 652 if (spsr & SPSR_SPRF) 653 disable_irq |= SPCR_SPRIE; 654 if (spsr & SPSR_SPTEF) 655 disable_irq |= SPCR_SPTIE; 656 657 if (disable_irq) { 658 ret = IRQ_HANDLED; 659 rspi_disable_irq(rspi, disable_irq); 660 wake_up(&rspi->wait); 661 } 662 663 return ret; 664 } 665 666 static int rspi_request_dma(struct rspi_data *rspi, 667 struct platform_device *pdev) 668 { 669 struct rspi_plat_data *rspi_pd = dev_get_platdata(&pdev->dev); 670 struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 671 dma_cap_mask_t mask; 672 struct dma_slave_config cfg; 673 int ret; 674 675 if (!res || !rspi_pd) 676 return 0; /* The driver assumes no error. */ 677 678 rspi->dma_width_16bit = rspi_pd->dma_width_16bit; 679 680 /* If the module receives data by DMAC, it also needs TX DMAC */ 681 if (rspi_pd->dma_rx_id && rspi_pd->dma_tx_id) { 682 dma_cap_zero(mask); 683 dma_cap_set(DMA_SLAVE, mask); 684 rspi->chan_rx = dma_request_channel(mask, shdma_chan_filter, 685 (void *)rspi_pd->dma_rx_id); 686 if (rspi->chan_rx) { 687 cfg.slave_id = rspi_pd->dma_rx_id; 688 cfg.direction = DMA_DEV_TO_MEM; 689 cfg.dst_addr = 0; 690 cfg.src_addr = res->start + RSPI_SPDR; 691 ret = dmaengine_slave_config(rspi->chan_rx, &cfg); 692 if (!ret) 693 dev_info(&pdev->dev, "Use DMA when rx.\n"); 694 else 695 return ret; 696 } 697 } 698 if (rspi_pd->dma_tx_id) { 699 dma_cap_zero(mask); 700 dma_cap_set(DMA_SLAVE, mask); 701 rspi->chan_tx = dma_request_channel(mask, shdma_chan_filter, 702 (void *)rspi_pd->dma_tx_id); 703 if (rspi->chan_tx) { 704 cfg.slave_id = rspi_pd->dma_tx_id; 705 cfg.direction = DMA_MEM_TO_DEV; 706 cfg.dst_addr = res->start + RSPI_SPDR; 707 cfg.src_addr = 0; 708 ret = dmaengine_slave_config(rspi->chan_tx, &cfg); 709 if (!ret) 710 dev_info(&pdev->dev, "Use DMA when tx\n"); 711 else 712 return ret; 713 } 714 } 715 716 return 0; 717 } 718 719 static void rspi_release_dma(struct rspi_data *rspi) 720 { 721 if (rspi->chan_tx) 722 dma_release_channel(rspi->chan_tx); 723 if (rspi->chan_rx) 724 dma_release_channel(rspi->chan_rx); 725 } 726 727 static int rspi_remove(struct platform_device *pdev) 728 { 729 struct rspi_data *rspi = spi_master_get(platform_get_drvdata(pdev)); 730 731 spi_unregister_master(rspi->master); 732 rspi_release_dma(rspi); 733 free_irq(platform_get_irq(pdev, 0), rspi); 734 clk_put(rspi->clk); 735 iounmap(rspi->addr); 736 spi_master_put(rspi->master); 737 738 return 0; 739 } 740 741 static int rspi_probe(struct platform_device *pdev) 742 { 743 struct resource *res; 744 struct spi_master *master; 745 struct rspi_data *rspi; 746 int ret, irq; 747 char clk_name[16]; 748 749 /* get base addr */ 750 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 751 if (unlikely(res == NULL)) { 752 dev_err(&pdev->dev, "invalid resource\n"); 753 return -EINVAL; 754 } 755 756 irq = platform_get_irq(pdev, 0); 757 if (irq < 0) { 758 dev_err(&pdev->dev, "platform_get_irq error\n"); 759 return -ENODEV; 760 } 761 762 master = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data)); 763 if (master == NULL) { 764 dev_err(&pdev->dev, "spi_alloc_master error.\n"); 765 return -ENOMEM; 766 } 767 768 rspi = spi_master_get_devdata(master); 769 platform_set_drvdata(pdev, rspi); 770 771 rspi->master = master; 772 rspi->addr = ioremap(res->start, resource_size(res)); 773 if (rspi->addr == NULL) { 774 dev_err(&pdev->dev, "ioremap error.\n"); 775 ret = -ENOMEM; 776 goto error1; 777 } 778 779 snprintf(clk_name, sizeof(clk_name), "rspi%d", pdev->id); 780 rspi->clk = clk_get(&pdev->dev, clk_name); 781 if (IS_ERR(rspi->clk)) { 782 dev_err(&pdev->dev, "cannot get clock\n"); 783 ret = PTR_ERR(rspi->clk); 784 goto error2; 785 } 786 clk_enable(rspi->clk); 787 788 INIT_LIST_HEAD(&rspi->queue); 789 spin_lock_init(&rspi->lock); 790 INIT_WORK(&rspi->ws, rspi_work); 791 init_waitqueue_head(&rspi->wait); 792 793 master->num_chipselect = 2; 794 master->bus_num = pdev->id; 795 master->setup = rspi_setup; 796 master->transfer = rspi_transfer; 797 master->cleanup = rspi_cleanup; 798 799 ret = request_irq(irq, rspi_irq, 0, dev_name(&pdev->dev), rspi); 800 if (ret < 0) { 801 dev_err(&pdev->dev, "request_irq error\n"); 802 goto error3; 803 } 804 805 rspi->irq = irq; 806 ret = rspi_request_dma(rspi, pdev); 807 if (ret < 0) { 808 dev_err(&pdev->dev, "rspi_request_dma failed.\n"); 809 goto error4; 810 } 811 812 ret = spi_register_master(master); 813 if (ret < 0) { 814 dev_err(&pdev->dev, "spi_register_master error.\n"); 815 goto error4; 816 } 817 818 dev_info(&pdev->dev, "probed\n"); 819 820 return 0; 821 822 error4: 823 rspi_release_dma(rspi); 824 free_irq(irq, rspi); 825 error3: 826 clk_put(rspi->clk); 827 error2: 828 iounmap(rspi->addr); 829 error1: 830 spi_master_put(master); 831 832 return ret; 833 } 834 835 static struct platform_driver rspi_driver = { 836 .probe = rspi_probe, 837 .remove = rspi_remove, 838 .driver = { 839 .name = "rspi", 840 .owner = THIS_MODULE, 841 }, 842 }; 843 module_platform_driver(rspi_driver); 844 845 MODULE_DESCRIPTION("Renesas RSPI bus driver"); 846 MODULE_LICENSE("GPL v2"); 847 MODULE_AUTHOR("Yoshihiro Shimoda"); 848 MODULE_ALIAS("platform:rspi"); 849