1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * OMAP2 McSPI controller driver 4 * 5 * Copyright (C) 2005, 2006 Nokia Corporation 6 * Author: Samuel Ortiz <samuel.ortiz@nokia.com> and 7 * Juha Yrjola <juha.yrjola@nokia.com> 8 */ 9 10 #include <linux/kernel.h> 11 #include <linux/interrupt.h> 12 #include <linux/module.h> 13 #include <linux/device.h> 14 #include <linux/delay.h> 15 #include <linux/dma-mapping.h> 16 #include <linux/dmaengine.h> 17 #include <linux/pinctrl/consumer.h> 18 #include <linux/platform_device.h> 19 #include <linux/err.h> 20 #include <linux/clk.h> 21 #include <linux/io.h> 22 #include <linux/slab.h> 23 #include <linux/pm_runtime.h> 24 #include <linux/of.h> 25 #include <linux/of_device.h> 26 #include <linux/gcd.h> 27 28 #include <linux/spi/spi.h> 29 30 #include <linux/platform_data/spi-omap2-mcspi.h> 31 32 #define OMAP2_MCSPI_MAX_FREQ 48000000 33 #define OMAP2_MCSPI_MAX_DIVIDER 4096 34 #define OMAP2_MCSPI_MAX_FIFODEPTH 64 35 #define OMAP2_MCSPI_MAX_FIFOWCNT 0xFFFF 36 #define SPI_AUTOSUSPEND_TIMEOUT 2000 37 38 #define OMAP2_MCSPI_REVISION 0x00 39 #define OMAP2_MCSPI_SYSSTATUS 0x14 40 #define OMAP2_MCSPI_IRQSTATUS 0x18 41 #define OMAP2_MCSPI_IRQENABLE 0x1c 42 #define OMAP2_MCSPI_WAKEUPENABLE 0x20 43 #define OMAP2_MCSPI_SYST 0x24 44 #define OMAP2_MCSPI_MODULCTRL 0x28 45 #define OMAP2_MCSPI_XFERLEVEL 0x7c 46 47 /* per-channel banks, 0x14 bytes each, first is: */ 48 #define OMAP2_MCSPI_CHCONF0 0x2c 49 #define OMAP2_MCSPI_CHSTAT0 0x30 50 #define OMAP2_MCSPI_CHCTRL0 0x34 51 #define OMAP2_MCSPI_TX0 0x38 52 #define OMAP2_MCSPI_RX0 0x3c 53 54 /* per-register bitmasks: */ 55 #define OMAP2_MCSPI_IRQSTATUS_EOW BIT(17) 56 57 #define OMAP2_MCSPI_MODULCTRL_SINGLE BIT(0) 58 #define OMAP2_MCSPI_MODULCTRL_MS BIT(2) 59 #define OMAP2_MCSPI_MODULCTRL_STEST BIT(3) 60 61 #define OMAP2_MCSPI_CHCONF_PHA BIT(0) 62 #define OMAP2_MCSPI_CHCONF_POL BIT(1) 63 #define OMAP2_MCSPI_CHCONF_CLKD_MASK (0x0f << 2) 64 #define OMAP2_MCSPI_CHCONF_EPOL BIT(6) 65 #define OMAP2_MCSPI_CHCONF_WL_MASK (0x1f << 7) 66 #define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY BIT(12) 67 #define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY BIT(13) 68 #define OMAP2_MCSPI_CHCONF_TRM_MASK (0x03 << 12) 69 #define OMAP2_MCSPI_CHCONF_DMAW BIT(14) 70 #define OMAP2_MCSPI_CHCONF_DMAR BIT(15) 71 #define OMAP2_MCSPI_CHCONF_DPE0 BIT(16) 72 #define OMAP2_MCSPI_CHCONF_DPE1 BIT(17) 73 #define OMAP2_MCSPI_CHCONF_IS BIT(18) 74 #define OMAP2_MCSPI_CHCONF_TURBO BIT(19) 75 #define OMAP2_MCSPI_CHCONF_FORCE BIT(20) 76 #define OMAP2_MCSPI_CHCONF_FFET BIT(27) 77 #define OMAP2_MCSPI_CHCONF_FFER BIT(28) 78 #define OMAP2_MCSPI_CHCONF_CLKG BIT(29) 79 80 #define OMAP2_MCSPI_CHSTAT_RXS BIT(0) 81 #define OMAP2_MCSPI_CHSTAT_TXS BIT(1) 82 #define OMAP2_MCSPI_CHSTAT_EOT BIT(2) 83 #define OMAP2_MCSPI_CHSTAT_TXFFE BIT(3) 84 85 #define OMAP2_MCSPI_CHCTRL_EN BIT(0) 86 #define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK (0xff << 8) 87 88 #define OMAP2_MCSPI_WAKEUPENABLE_WKEN BIT(0) 89 90 /* We have 2 DMA channels per CS, one for RX and one for TX */ 91 struct omap2_mcspi_dma { 92 struct dma_chan *dma_tx; 93 struct dma_chan *dma_rx; 94 95 struct completion dma_tx_completion; 96 struct completion dma_rx_completion; 97 98 char dma_rx_ch_name[14]; 99 char dma_tx_ch_name[14]; 100 }; 101 102 /* use PIO for small transfers, avoiding DMA setup/teardown overhead and 103 * cache operations; better heuristics consider wordsize and bitrate. 104 */ 105 #define DMA_MIN_BYTES 160 106 107 108 /* 109 * Used for context save and restore, structure members to be updated whenever 110 * corresponding registers are modified. 111 */ 112 struct omap2_mcspi_regs { 113 u32 modulctrl; 114 u32 wakeupenable; 115 struct list_head cs; 116 }; 117 118 struct omap2_mcspi { 119 struct completion txdone; 120 struct spi_master *master; 121 /* Virtual base address of the controller */ 122 void __iomem *base; 123 unsigned long phys; 124 /* SPI1 has 4 channels, while SPI2 has 2 */ 125 struct omap2_mcspi_dma *dma_channels; 126 struct device *dev; 127 struct omap2_mcspi_regs ctx; 128 int fifo_depth; 129 bool slave_aborted; 130 unsigned int pin_dir:1; 131 size_t max_xfer_len; 132 }; 133 134 struct omap2_mcspi_cs { 135 void __iomem *base; 136 unsigned long phys; 137 int word_len; 138 u16 mode; 139 struct list_head node; 140 /* Context save and restore shadow register */ 141 u32 chconf0, chctrl0; 142 }; 143 144 static inline void mcspi_write_reg(struct spi_master *master, 145 int idx, u32 val) 146 { 147 struct omap2_mcspi *mcspi = spi_master_get_devdata(master); 148 149 writel_relaxed(val, mcspi->base + idx); 150 } 151 152 static inline u32 mcspi_read_reg(struct spi_master *master, int idx) 153 { 154 struct omap2_mcspi *mcspi = spi_master_get_devdata(master); 155 156 return readl_relaxed(mcspi->base + idx); 157 } 158 159 static inline void mcspi_write_cs_reg(const struct spi_device *spi, 160 int idx, u32 val) 161 { 162 struct omap2_mcspi_cs *cs = spi->controller_state; 163 164 writel_relaxed(val, cs->base + idx); 165 } 166 167 static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx) 168 { 169 struct omap2_mcspi_cs *cs = spi->controller_state; 170 171 return readl_relaxed(cs->base + idx); 172 } 173 174 static inline u32 mcspi_cached_chconf0(const struct spi_device *spi) 175 { 176 struct omap2_mcspi_cs *cs = spi->controller_state; 177 178 return cs->chconf0; 179 } 180 181 static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val) 182 { 183 struct omap2_mcspi_cs *cs = spi->controller_state; 184 185 cs->chconf0 = val; 186 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val); 187 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0); 188 } 189 190 static inline int mcspi_bytes_per_word(int word_len) 191 { 192 if (word_len <= 8) 193 return 1; 194 else if (word_len <= 16) 195 return 2; 196 else /* word_len <= 32 */ 197 return 4; 198 } 199 200 static void omap2_mcspi_set_dma_req(const struct spi_device *spi, 201 int is_read, int enable) 202 { 203 u32 l, rw; 204 205 l = mcspi_cached_chconf0(spi); 206 207 if (is_read) /* 1 is read, 0 write */ 208 rw = OMAP2_MCSPI_CHCONF_DMAR; 209 else 210 rw = OMAP2_MCSPI_CHCONF_DMAW; 211 212 if (enable) 213 l |= rw; 214 else 215 l &= ~rw; 216 217 mcspi_write_chconf0(spi, l); 218 } 219 220 static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable) 221 { 222 struct omap2_mcspi_cs *cs = spi->controller_state; 223 u32 l; 224 225 l = cs->chctrl0; 226 if (enable) 227 l |= OMAP2_MCSPI_CHCTRL_EN; 228 else 229 l &= ~OMAP2_MCSPI_CHCTRL_EN; 230 cs->chctrl0 = l; 231 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0); 232 /* Flash post-writes */ 233 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0); 234 } 235 236 static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable) 237 { 238 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master); 239 u32 l; 240 241 /* The controller handles the inverted chip selects 242 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert 243 * the inversion from the core spi_set_cs function. 244 */ 245 if (spi->mode & SPI_CS_HIGH) 246 enable = !enable; 247 248 if (spi->controller_state) { 249 int err = pm_runtime_resume_and_get(mcspi->dev); 250 if (err < 0) { 251 dev_err(mcspi->dev, "failed to get sync: %d\n", err); 252 return; 253 } 254 255 l = mcspi_cached_chconf0(spi); 256 257 if (enable) 258 l &= ~OMAP2_MCSPI_CHCONF_FORCE; 259 else 260 l |= OMAP2_MCSPI_CHCONF_FORCE; 261 262 mcspi_write_chconf0(spi, l); 263 264 pm_runtime_mark_last_busy(mcspi->dev); 265 pm_runtime_put_autosuspend(mcspi->dev); 266 } 267 } 268 269 static void omap2_mcspi_set_mode(struct spi_master *master) 270 { 271 struct omap2_mcspi *mcspi = spi_master_get_devdata(master); 272 struct omap2_mcspi_regs *ctx = &mcspi->ctx; 273 u32 l; 274 275 /* 276 * Choose master or slave mode 277 */ 278 l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL); 279 l &= ~(OMAP2_MCSPI_MODULCTRL_STEST); 280 if (spi_controller_is_slave(master)) { 281 l |= (OMAP2_MCSPI_MODULCTRL_MS); 282 } else { 283 l &= ~(OMAP2_MCSPI_MODULCTRL_MS); 284 l |= OMAP2_MCSPI_MODULCTRL_SINGLE; 285 } 286 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l); 287 288 ctx->modulctrl = l; 289 } 290 291 static void omap2_mcspi_set_fifo(const struct spi_device *spi, 292 struct spi_transfer *t, int enable) 293 { 294 struct spi_master *master = spi->master; 295 struct omap2_mcspi_cs *cs = spi->controller_state; 296 struct omap2_mcspi *mcspi; 297 unsigned int wcnt; 298 int max_fifo_depth, bytes_per_word; 299 u32 chconf, xferlevel; 300 301 mcspi = spi_master_get_devdata(master); 302 303 chconf = mcspi_cached_chconf0(spi); 304 if (enable) { 305 bytes_per_word = mcspi_bytes_per_word(cs->word_len); 306 if (t->len % bytes_per_word != 0) 307 goto disable_fifo; 308 309 if (t->rx_buf != NULL && t->tx_buf != NULL) 310 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2; 311 else 312 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH; 313 314 wcnt = t->len / bytes_per_word; 315 if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT) 316 goto disable_fifo; 317 318 xferlevel = wcnt << 16; 319 if (t->rx_buf != NULL) { 320 chconf |= OMAP2_MCSPI_CHCONF_FFER; 321 xferlevel |= (bytes_per_word - 1) << 8; 322 } 323 324 if (t->tx_buf != NULL) { 325 chconf |= OMAP2_MCSPI_CHCONF_FFET; 326 xferlevel |= bytes_per_word - 1; 327 } 328 329 mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel); 330 mcspi_write_chconf0(spi, chconf); 331 mcspi->fifo_depth = max_fifo_depth; 332 333 return; 334 } 335 336 disable_fifo: 337 if (t->rx_buf != NULL) 338 chconf &= ~OMAP2_MCSPI_CHCONF_FFER; 339 340 if (t->tx_buf != NULL) 341 chconf &= ~OMAP2_MCSPI_CHCONF_FFET; 342 343 mcspi_write_chconf0(spi, chconf); 344 mcspi->fifo_depth = 0; 345 } 346 347 static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit) 348 { 349 unsigned long timeout; 350 351 timeout = jiffies + msecs_to_jiffies(1000); 352 while (!(readl_relaxed(reg) & bit)) { 353 if (time_after(jiffies, timeout)) { 354 if (!(readl_relaxed(reg) & bit)) 355 return -ETIMEDOUT; 356 else 357 return 0; 358 } 359 cpu_relax(); 360 } 361 return 0; 362 } 363 364 static int mcspi_wait_for_completion(struct omap2_mcspi *mcspi, 365 struct completion *x) 366 { 367 if (spi_controller_is_slave(mcspi->master)) { 368 if (wait_for_completion_interruptible(x) || 369 mcspi->slave_aborted) 370 return -EINTR; 371 } else { 372 wait_for_completion(x); 373 } 374 375 return 0; 376 } 377 378 static void omap2_mcspi_rx_callback(void *data) 379 { 380 struct spi_device *spi = data; 381 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master); 382 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select]; 383 384 /* We must disable the DMA RX request */ 385 omap2_mcspi_set_dma_req(spi, 1, 0); 386 387 complete(&mcspi_dma->dma_rx_completion); 388 } 389 390 static void omap2_mcspi_tx_callback(void *data) 391 { 392 struct spi_device *spi = data; 393 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master); 394 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select]; 395 396 /* We must disable the DMA TX request */ 397 omap2_mcspi_set_dma_req(spi, 0, 0); 398 399 complete(&mcspi_dma->dma_tx_completion); 400 } 401 402 static void omap2_mcspi_tx_dma(struct spi_device *spi, 403 struct spi_transfer *xfer, 404 struct dma_slave_config cfg) 405 { 406 struct omap2_mcspi *mcspi; 407 struct omap2_mcspi_dma *mcspi_dma; 408 struct dma_async_tx_descriptor *tx; 409 410 mcspi = spi_master_get_devdata(spi->master); 411 mcspi_dma = &mcspi->dma_channels[spi->chip_select]; 412 413 dmaengine_slave_config(mcspi_dma->dma_tx, &cfg); 414 415 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl, 416 xfer->tx_sg.nents, 417 DMA_MEM_TO_DEV, 418 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 419 if (tx) { 420 tx->callback = omap2_mcspi_tx_callback; 421 tx->callback_param = spi; 422 dmaengine_submit(tx); 423 } else { 424 /* FIXME: fall back to PIO? */ 425 } 426 dma_async_issue_pending(mcspi_dma->dma_tx); 427 omap2_mcspi_set_dma_req(spi, 0, 1); 428 } 429 430 static unsigned 431 omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer, 432 struct dma_slave_config cfg, 433 unsigned es) 434 { 435 struct omap2_mcspi *mcspi; 436 struct omap2_mcspi_dma *mcspi_dma; 437 unsigned int count, transfer_reduction = 0; 438 struct scatterlist *sg_out[2]; 439 int nb_sizes = 0, out_mapped_nents[2], ret, x; 440 size_t sizes[2]; 441 u32 l; 442 int elements = 0; 443 int word_len, element_count; 444 struct omap2_mcspi_cs *cs = spi->controller_state; 445 void __iomem *chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0; 446 struct dma_async_tx_descriptor *tx; 447 448 mcspi = spi_master_get_devdata(spi->master); 449 mcspi_dma = &mcspi->dma_channels[spi->chip_select]; 450 count = xfer->len; 451 452 /* 453 * In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM 454 * it mentions reducing DMA transfer length by one element in master 455 * normal mode. 456 */ 457 if (mcspi->fifo_depth == 0) 458 transfer_reduction = es; 459 460 word_len = cs->word_len; 461 l = mcspi_cached_chconf0(spi); 462 463 if (word_len <= 8) 464 element_count = count; 465 else if (word_len <= 16) 466 element_count = count >> 1; 467 else /* word_len <= 32 */ 468 element_count = count >> 2; 469 470 471 dmaengine_slave_config(mcspi_dma->dma_rx, &cfg); 472 473 /* 474 * Reduce DMA transfer length by one more if McSPI is 475 * configured in turbo mode. 476 */ 477 if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0) 478 transfer_reduction += es; 479 480 if (transfer_reduction) { 481 /* Split sgl into two. The second sgl won't be used. */ 482 sizes[0] = count - transfer_reduction; 483 sizes[1] = transfer_reduction; 484 nb_sizes = 2; 485 } else { 486 /* 487 * Don't bother splitting the sgl. This essentially 488 * clones the original sgl. 489 */ 490 sizes[0] = count; 491 nb_sizes = 1; 492 } 493 494 ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents, 0, nb_sizes, 495 sizes, sg_out, out_mapped_nents, GFP_KERNEL); 496 497 if (ret < 0) { 498 dev_err(&spi->dev, "sg_split failed\n"); 499 return 0; 500 } 501 502 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, sg_out[0], 503 out_mapped_nents[0], DMA_DEV_TO_MEM, 504 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 505 if (tx) { 506 tx->callback = omap2_mcspi_rx_callback; 507 tx->callback_param = spi; 508 dmaengine_submit(tx); 509 } else { 510 /* FIXME: fall back to PIO? */ 511 } 512 513 dma_async_issue_pending(mcspi_dma->dma_rx); 514 omap2_mcspi_set_dma_req(spi, 1, 1); 515 516 ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion); 517 if (ret || mcspi->slave_aborted) { 518 dmaengine_terminate_sync(mcspi_dma->dma_rx); 519 omap2_mcspi_set_dma_req(spi, 1, 0); 520 return 0; 521 } 522 523 for (x = 0; x < nb_sizes; x++) 524 kfree(sg_out[x]); 525 526 if (mcspi->fifo_depth > 0) 527 return count; 528 529 /* 530 * Due to the DMA transfer length reduction the missing bytes must 531 * be read manually to receive all of the expected data. 532 */ 533 omap2_mcspi_set_enable(spi, 0); 534 535 elements = element_count - 1; 536 537 if (l & OMAP2_MCSPI_CHCONF_TURBO) { 538 elements--; 539 540 if (!mcspi_wait_for_reg_bit(chstat_reg, 541 OMAP2_MCSPI_CHSTAT_RXS)) { 542 u32 w; 543 544 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0); 545 if (word_len <= 8) 546 ((u8 *)xfer->rx_buf)[elements++] = w; 547 else if (word_len <= 16) 548 ((u16 *)xfer->rx_buf)[elements++] = w; 549 else /* word_len <= 32 */ 550 ((u32 *)xfer->rx_buf)[elements++] = w; 551 } else { 552 int bytes_per_word = mcspi_bytes_per_word(word_len); 553 dev_err(&spi->dev, "DMA RX penultimate word empty\n"); 554 count -= (bytes_per_word << 1); 555 omap2_mcspi_set_enable(spi, 1); 556 return count; 557 } 558 } 559 if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) { 560 u32 w; 561 562 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0); 563 if (word_len <= 8) 564 ((u8 *)xfer->rx_buf)[elements] = w; 565 else if (word_len <= 16) 566 ((u16 *)xfer->rx_buf)[elements] = w; 567 else /* word_len <= 32 */ 568 ((u32 *)xfer->rx_buf)[elements] = w; 569 } else { 570 dev_err(&spi->dev, "DMA RX last word empty\n"); 571 count -= mcspi_bytes_per_word(word_len); 572 } 573 omap2_mcspi_set_enable(spi, 1); 574 return count; 575 } 576 577 static unsigned 578 omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) 579 { 580 struct omap2_mcspi *mcspi; 581 struct omap2_mcspi_cs *cs = spi->controller_state; 582 struct omap2_mcspi_dma *mcspi_dma; 583 unsigned int count; 584 u8 *rx; 585 const u8 *tx; 586 struct dma_slave_config cfg; 587 enum dma_slave_buswidth width; 588 unsigned es; 589 void __iomem *chstat_reg; 590 void __iomem *irqstat_reg; 591 int wait_res; 592 593 mcspi = spi_master_get_devdata(spi->master); 594 mcspi_dma = &mcspi->dma_channels[spi->chip_select]; 595 596 if (cs->word_len <= 8) { 597 width = DMA_SLAVE_BUSWIDTH_1_BYTE; 598 es = 1; 599 } else if (cs->word_len <= 16) { 600 width = DMA_SLAVE_BUSWIDTH_2_BYTES; 601 es = 2; 602 } else { 603 width = DMA_SLAVE_BUSWIDTH_4_BYTES; 604 es = 4; 605 } 606 607 count = xfer->len; 608 609 memset(&cfg, 0, sizeof(cfg)); 610 cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0; 611 cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0; 612 cfg.src_addr_width = width; 613 cfg.dst_addr_width = width; 614 cfg.src_maxburst = 1; 615 cfg.dst_maxburst = 1; 616 617 rx = xfer->rx_buf; 618 tx = xfer->tx_buf; 619 620 mcspi->slave_aborted = false; 621 reinit_completion(&mcspi_dma->dma_tx_completion); 622 reinit_completion(&mcspi_dma->dma_rx_completion); 623 reinit_completion(&mcspi->txdone); 624 if (tx) { 625 /* Enable EOW IRQ to know end of tx in slave mode */ 626 if (spi_controller_is_slave(spi->master)) 627 mcspi_write_reg(spi->master, 628 OMAP2_MCSPI_IRQENABLE, 629 OMAP2_MCSPI_IRQSTATUS_EOW); 630 omap2_mcspi_tx_dma(spi, xfer, cfg); 631 } 632 633 if (rx != NULL) 634 count = omap2_mcspi_rx_dma(spi, xfer, cfg, es); 635 636 if (tx != NULL) { 637 int ret; 638 639 ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion); 640 if (ret || mcspi->slave_aborted) { 641 dmaengine_terminate_sync(mcspi_dma->dma_tx); 642 omap2_mcspi_set_dma_req(spi, 0, 0); 643 return 0; 644 } 645 646 if (spi_controller_is_slave(mcspi->master)) { 647 ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone); 648 if (ret || mcspi->slave_aborted) 649 return 0; 650 } 651 652 if (mcspi->fifo_depth > 0) { 653 irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS; 654 655 if (mcspi_wait_for_reg_bit(irqstat_reg, 656 OMAP2_MCSPI_IRQSTATUS_EOW) < 0) 657 dev_err(&spi->dev, "EOW timed out\n"); 658 659 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS, 660 OMAP2_MCSPI_IRQSTATUS_EOW); 661 } 662 663 /* for TX_ONLY mode, be sure all words have shifted out */ 664 if (rx == NULL) { 665 chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0; 666 if (mcspi->fifo_depth > 0) { 667 wait_res = mcspi_wait_for_reg_bit(chstat_reg, 668 OMAP2_MCSPI_CHSTAT_TXFFE); 669 if (wait_res < 0) 670 dev_err(&spi->dev, "TXFFE timed out\n"); 671 } else { 672 wait_res = mcspi_wait_for_reg_bit(chstat_reg, 673 OMAP2_MCSPI_CHSTAT_TXS); 674 if (wait_res < 0) 675 dev_err(&spi->dev, "TXS timed out\n"); 676 } 677 if (wait_res >= 0 && 678 (mcspi_wait_for_reg_bit(chstat_reg, 679 OMAP2_MCSPI_CHSTAT_EOT) < 0)) 680 dev_err(&spi->dev, "EOT timed out\n"); 681 } 682 } 683 return count; 684 } 685 686 static unsigned 687 omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) 688 { 689 struct omap2_mcspi_cs *cs = spi->controller_state; 690 unsigned int count, c; 691 u32 l; 692 void __iomem *base = cs->base; 693 void __iomem *tx_reg; 694 void __iomem *rx_reg; 695 void __iomem *chstat_reg; 696 int word_len; 697 698 count = xfer->len; 699 c = count; 700 word_len = cs->word_len; 701 702 l = mcspi_cached_chconf0(spi); 703 704 /* We store the pre-calculated register addresses on stack to speed 705 * up the transfer loop. */ 706 tx_reg = base + OMAP2_MCSPI_TX0; 707 rx_reg = base + OMAP2_MCSPI_RX0; 708 chstat_reg = base + OMAP2_MCSPI_CHSTAT0; 709 710 if (c < (word_len>>3)) 711 return 0; 712 713 if (word_len <= 8) { 714 u8 *rx; 715 const u8 *tx; 716 717 rx = xfer->rx_buf; 718 tx = xfer->tx_buf; 719 720 do { 721 c -= 1; 722 if (tx != NULL) { 723 if (mcspi_wait_for_reg_bit(chstat_reg, 724 OMAP2_MCSPI_CHSTAT_TXS) < 0) { 725 dev_err(&spi->dev, "TXS timed out\n"); 726 goto out; 727 } 728 dev_vdbg(&spi->dev, "write-%d %02x\n", 729 word_len, *tx); 730 writel_relaxed(*tx++, tx_reg); 731 } 732 if (rx != NULL) { 733 if (mcspi_wait_for_reg_bit(chstat_reg, 734 OMAP2_MCSPI_CHSTAT_RXS) < 0) { 735 dev_err(&spi->dev, "RXS timed out\n"); 736 goto out; 737 } 738 739 if (c == 1 && tx == NULL && 740 (l & OMAP2_MCSPI_CHCONF_TURBO)) { 741 omap2_mcspi_set_enable(spi, 0); 742 *rx++ = readl_relaxed(rx_reg); 743 dev_vdbg(&spi->dev, "read-%d %02x\n", 744 word_len, *(rx - 1)); 745 if (mcspi_wait_for_reg_bit(chstat_reg, 746 OMAP2_MCSPI_CHSTAT_RXS) < 0) { 747 dev_err(&spi->dev, 748 "RXS timed out\n"); 749 goto out; 750 } 751 c = 0; 752 } else if (c == 0 && tx == NULL) { 753 omap2_mcspi_set_enable(spi, 0); 754 } 755 756 *rx++ = readl_relaxed(rx_reg); 757 dev_vdbg(&spi->dev, "read-%d %02x\n", 758 word_len, *(rx - 1)); 759 } 760 /* Add word delay between each word */ 761 spi_delay_exec(&xfer->word_delay, xfer); 762 } while (c); 763 } else if (word_len <= 16) { 764 u16 *rx; 765 const u16 *tx; 766 767 rx = xfer->rx_buf; 768 tx = xfer->tx_buf; 769 do { 770 c -= 2; 771 if (tx != NULL) { 772 if (mcspi_wait_for_reg_bit(chstat_reg, 773 OMAP2_MCSPI_CHSTAT_TXS) < 0) { 774 dev_err(&spi->dev, "TXS timed out\n"); 775 goto out; 776 } 777 dev_vdbg(&spi->dev, "write-%d %04x\n", 778 word_len, *tx); 779 writel_relaxed(*tx++, tx_reg); 780 } 781 if (rx != NULL) { 782 if (mcspi_wait_for_reg_bit(chstat_reg, 783 OMAP2_MCSPI_CHSTAT_RXS) < 0) { 784 dev_err(&spi->dev, "RXS timed out\n"); 785 goto out; 786 } 787 788 if (c == 2 && tx == NULL && 789 (l & OMAP2_MCSPI_CHCONF_TURBO)) { 790 omap2_mcspi_set_enable(spi, 0); 791 *rx++ = readl_relaxed(rx_reg); 792 dev_vdbg(&spi->dev, "read-%d %04x\n", 793 word_len, *(rx - 1)); 794 if (mcspi_wait_for_reg_bit(chstat_reg, 795 OMAP2_MCSPI_CHSTAT_RXS) < 0) { 796 dev_err(&spi->dev, 797 "RXS timed out\n"); 798 goto out; 799 } 800 c = 0; 801 } else if (c == 0 && tx == NULL) { 802 omap2_mcspi_set_enable(spi, 0); 803 } 804 805 *rx++ = readl_relaxed(rx_reg); 806 dev_vdbg(&spi->dev, "read-%d %04x\n", 807 word_len, *(rx - 1)); 808 } 809 /* Add word delay between each word */ 810 spi_delay_exec(&xfer->word_delay, xfer); 811 } while (c >= 2); 812 } else if (word_len <= 32) { 813 u32 *rx; 814 const u32 *tx; 815 816 rx = xfer->rx_buf; 817 tx = xfer->tx_buf; 818 do { 819 c -= 4; 820 if (tx != NULL) { 821 if (mcspi_wait_for_reg_bit(chstat_reg, 822 OMAP2_MCSPI_CHSTAT_TXS) < 0) { 823 dev_err(&spi->dev, "TXS timed out\n"); 824 goto out; 825 } 826 dev_vdbg(&spi->dev, "write-%d %08x\n", 827 word_len, *tx); 828 writel_relaxed(*tx++, tx_reg); 829 } 830 if (rx != NULL) { 831 if (mcspi_wait_for_reg_bit(chstat_reg, 832 OMAP2_MCSPI_CHSTAT_RXS) < 0) { 833 dev_err(&spi->dev, "RXS timed out\n"); 834 goto out; 835 } 836 837 if (c == 4 && tx == NULL && 838 (l & OMAP2_MCSPI_CHCONF_TURBO)) { 839 omap2_mcspi_set_enable(spi, 0); 840 *rx++ = readl_relaxed(rx_reg); 841 dev_vdbg(&spi->dev, "read-%d %08x\n", 842 word_len, *(rx - 1)); 843 if (mcspi_wait_for_reg_bit(chstat_reg, 844 OMAP2_MCSPI_CHSTAT_RXS) < 0) { 845 dev_err(&spi->dev, 846 "RXS timed out\n"); 847 goto out; 848 } 849 c = 0; 850 } else if (c == 0 && tx == NULL) { 851 omap2_mcspi_set_enable(spi, 0); 852 } 853 854 *rx++ = readl_relaxed(rx_reg); 855 dev_vdbg(&spi->dev, "read-%d %08x\n", 856 word_len, *(rx - 1)); 857 } 858 /* Add word delay between each word */ 859 spi_delay_exec(&xfer->word_delay, xfer); 860 } while (c >= 4); 861 } 862 863 /* for TX_ONLY mode, be sure all words have shifted out */ 864 if (xfer->rx_buf == NULL) { 865 if (mcspi_wait_for_reg_bit(chstat_reg, 866 OMAP2_MCSPI_CHSTAT_TXS) < 0) { 867 dev_err(&spi->dev, "TXS timed out\n"); 868 } else if (mcspi_wait_for_reg_bit(chstat_reg, 869 OMAP2_MCSPI_CHSTAT_EOT) < 0) 870 dev_err(&spi->dev, "EOT timed out\n"); 871 872 /* disable chan to purge rx datas received in TX_ONLY transfer, 873 * otherwise these rx datas will affect the direct following 874 * RX_ONLY transfer. 875 */ 876 omap2_mcspi_set_enable(spi, 0); 877 } 878 out: 879 omap2_mcspi_set_enable(spi, 1); 880 return count - c; 881 } 882 883 static u32 omap2_mcspi_calc_divisor(u32 speed_hz) 884 { 885 u32 div; 886 887 for (div = 0; div < 15; div++) 888 if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div)) 889 return div; 890 891 return 15; 892 } 893 894 /* called only when no transfer is active to this device */ 895 static int omap2_mcspi_setup_transfer(struct spi_device *spi, 896 struct spi_transfer *t) 897 { 898 struct omap2_mcspi_cs *cs = spi->controller_state; 899 struct omap2_mcspi *mcspi; 900 u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0; 901 u8 word_len = spi->bits_per_word; 902 u32 speed_hz = spi->max_speed_hz; 903 904 mcspi = spi_master_get_devdata(spi->master); 905 906 if (t != NULL && t->bits_per_word) 907 word_len = t->bits_per_word; 908 909 cs->word_len = word_len; 910 911 if (t && t->speed_hz) 912 speed_hz = t->speed_hz; 913 914 speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ); 915 if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) { 916 clkd = omap2_mcspi_calc_divisor(speed_hz); 917 speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd; 918 clkg = 0; 919 } else { 920 div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz; 921 speed_hz = OMAP2_MCSPI_MAX_FREQ / div; 922 clkd = (div - 1) & 0xf; 923 extclk = (div - 1) >> 4; 924 clkg = OMAP2_MCSPI_CHCONF_CLKG; 925 } 926 927 l = mcspi_cached_chconf0(spi); 928 929 /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS 930 * REVISIT: this controller could support SPI_3WIRE mode. 931 */ 932 if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) { 933 l &= ~OMAP2_MCSPI_CHCONF_IS; 934 l &= ~OMAP2_MCSPI_CHCONF_DPE1; 935 l |= OMAP2_MCSPI_CHCONF_DPE0; 936 } else { 937 l |= OMAP2_MCSPI_CHCONF_IS; 938 l |= OMAP2_MCSPI_CHCONF_DPE1; 939 l &= ~OMAP2_MCSPI_CHCONF_DPE0; 940 } 941 942 /* wordlength */ 943 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK; 944 l |= (word_len - 1) << 7; 945 946 /* set chipselect polarity; manage with FORCE */ 947 if (!(spi->mode & SPI_CS_HIGH)) 948 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */ 949 else 950 l &= ~OMAP2_MCSPI_CHCONF_EPOL; 951 952 /* set clock divisor */ 953 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK; 954 l |= clkd << 2; 955 956 /* set clock granularity */ 957 l &= ~OMAP2_MCSPI_CHCONF_CLKG; 958 l |= clkg; 959 if (clkg) { 960 cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK; 961 cs->chctrl0 |= extclk << 8; 962 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0); 963 } 964 965 /* set SPI mode 0..3 */ 966 if (spi->mode & SPI_CPOL) 967 l |= OMAP2_MCSPI_CHCONF_POL; 968 else 969 l &= ~OMAP2_MCSPI_CHCONF_POL; 970 if (spi->mode & SPI_CPHA) 971 l |= OMAP2_MCSPI_CHCONF_PHA; 972 else 973 l &= ~OMAP2_MCSPI_CHCONF_PHA; 974 975 mcspi_write_chconf0(spi, l); 976 977 cs->mode = spi->mode; 978 979 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n", 980 speed_hz, 981 (spi->mode & SPI_CPHA) ? "trailing" : "leading", 982 (spi->mode & SPI_CPOL) ? "inverted" : "normal"); 983 984 return 0; 985 } 986 987 /* 988 * Note that we currently allow DMA only if we get a channel 989 * for both rx and tx. Otherwise we'll do PIO for both rx and tx. 990 */ 991 static int omap2_mcspi_request_dma(struct omap2_mcspi *mcspi, 992 struct omap2_mcspi_dma *mcspi_dma) 993 { 994 int ret = 0; 995 996 mcspi_dma->dma_rx = dma_request_chan(mcspi->dev, 997 mcspi_dma->dma_rx_ch_name); 998 if (IS_ERR(mcspi_dma->dma_rx)) { 999 ret = PTR_ERR(mcspi_dma->dma_rx); 1000 mcspi_dma->dma_rx = NULL; 1001 goto no_dma; 1002 } 1003 1004 mcspi_dma->dma_tx = dma_request_chan(mcspi->dev, 1005 mcspi_dma->dma_tx_ch_name); 1006 if (IS_ERR(mcspi_dma->dma_tx)) { 1007 ret = PTR_ERR(mcspi_dma->dma_tx); 1008 mcspi_dma->dma_tx = NULL; 1009 dma_release_channel(mcspi_dma->dma_rx); 1010 mcspi_dma->dma_rx = NULL; 1011 } 1012 1013 init_completion(&mcspi_dma->dma_rx_completion); 1014 init_completion(&mcspi_dma->dma_tx_completion); 1015 1016 no_dma: 1017 return ret; 1018 } 1019 1020 static void omap2_mcspi_release_dma(struct spi_master *master) 1021 { 1022 struct omap2_mcspi *mcspi = spi_master_get_devdata(master); 1023 struct omap2_mcspi_dma *mcspi_dma; 1024 int i; 1025 1026 for (i = 0; i < master->num_chipselect; i++) { 1027 mcspi_dma = &mcspi->dma_channels[i]; 1028 1029 if (mcspi_dma->dma_rx) { 1030 dma_release_channel(mcspi_dma->dma_rx); 1031 mcspi_dma->dma_rx = NULL; 1032 } 1033 if (mcspi_dma->dma_tx) { 1034 dma_release_channel(mcspi_dma->dma_tx); 1035 mcspi_dma->dma_tx = NULL; 1036 } 1037 } 1038 } 1039 1040 static void omap2_mcspi_cleanup(struct spi_device *spi) 1041 { 1042 struct omap2_mcspi_cs *cs; 1043 1044 if (spi->controller_state) { 1045 /* Unlink controller state from context save list */ 1046 cs = spi->controller_state; 1047 list_del(&cs->node); 1048 1049 kfree(cs); 1050 } 1051 } 1052 1053 static int omap2_mcspi_setup(struct spi_device *spi) 1054 { 1055 bool initial_setup = false; 1056 int ret; 1057 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master); 1058 struct omap2_mcspi_regs *ctx = &mcspi->ctx; 1059 struct omap2_mcspi_cs *cs = spi->controller_state; 1060 1061 if (!cs) { 1062 cs = kzalloc(sizeof(*cs), GFP_KERNEL); 1063 if (!cs) 1064 return -ENOMEM; 1065 cs->base = mcspi->base + spi->chip_select * 0x14; 1066 cs->phys = mcspi->phys + spi->chip_select * 0x14; 1067 cs->mode = 0; 1068 cs->chconf0 = 0; 1069 cs->chctrl0 = 0; 1070 spi->controller_state = cs; 1071 /* Link this to context save list */ 1072 list_add_tail(&cs->node, &ctx->cs); 1073 initial_setup = true; 1074 } 1075 1076 ret = pm_runtime_resume_and_get(mcspi->dev); 1077 if (ret < 0) { 1078 if (initial_setup) 1079 omap2_mcspi_cleanup(spi); 1080 1081 return ret; 1082 } 1083 1084 ret = omap2_mcspi_setup_transfer(spi, NULL); 1085 if (ret && initial_setup) 1086 omap2_mcspi_cleanup(spi); 1087 1088 pm_runtime_mark_last_busy(mcspi->dev); 1089 pm_runtime_put_autosuspend(mcspi->dev); 1090 1091 return ret; 1092 } 1093 1094 static irqreturn_t omap2_mcspi_irq_handler(int irq, void *data) 1095 { 1096 struct omap2_mcspi *mcspi = data; 1097 u32 irqstat; 1098 1099 irqstat = mcspi_read_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS); 1100 if (!irqstat) 1101 return IRQ_NONE; 1102 1103 /* Disable IRQ and wakeup slave xfer task */ 1104 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQENABLE, 0); 1105 if (irqstat & OMAP2_MCSPI_IRQSTATUS_EOW) 1106 complete(&mcspi->txdone); 1107 1108 return IRQ_HANDLED; 1109 } 1110 1111 static int omap2_mcspi_slave_abort(struct spi_master *master) 1112 { 1113 struct omap2_mcspi *mcspi = spi_master_get_devdata(master); 1114 struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels; 1115 1116 mcspi->slave_aborted = true; 1117 complete(&mcspi_dma->dma_rx_completion); 1118 complete(&mcspi_dma->dma_tx_completion); 1119 complete(&mcspi->txdone); 1120 1121 return 0; 1122 } 1123 1124 static int omap2_mcspi_transfer_one(struct spi_master *master, 1125 struct spi_device *spi, 1126 struct spi_transfer *t) 1127 { 1128 1129 /* We only enable one channel at a time -- the one whose message is 1130 * -- although this controller would gladly 1131 * arbitrate among multiple channels. This corresponds to "single 1132 * channel" master mode. As a side effect, we need to manage the 1133 * chipselect with the FORCE bit ... CS != channel enable. 1134 */ 1135 1136 struct omap2_mcspi *mcspi; 1137 struct omap2_mcspi_dma *mcspi_dma; 1138 struct omap2_mcspi_cs *cs; 1139 struct omap2_mcspi_device_config *cd; 1140 int par_override = 0; 1141 int status = 0; 1142 u32 chconf; 1143 1144 mcspi = spi_master_get_devdata(master); 1145 mcspi_dma = mcspi->dma_channels + spi->chip_select; 1146 cs = spi->controller_state; 1147 cd = spi->controller_data; 1148 1149 /* 1150 * The slave driver could have changed spi->mode in which case 1151 * it will be different from cs->mode (the current hardware setup). 1152 * If so, set par_override (even though its not a parity issue) so 1153 * omap2_mcspi_setup_transfer will be called to configure the hardware 1154 * with the correct mode on the first iteration of the loop below. 1155 */ 1156 if (spi->mode != cs->mode) 1157 par_override = 1; 1158 1159 omap2_mcspi_set_enable(spi, 0); 1160 1161 if (spi->cs_gpiod) 1162 omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH); 1163 1164 if (par_override || 1165 (t->speed_hz != spi->max_speed_hz) || 1166 (t->bits_per_word != spi->bits_per_word)) { 1167 par_override = 1; 1168 status = omap2_mcspi_setup_transfer(spi, t); 1169 if (status < 0) 1170 goto out; 1171 if (t->speed_hz == spi->max_speed_hz && 1172 t->bits_per_word == spi->bits_per_word) 1173 par_override = 0; 1174 } 1175 if (cd && cd->cs_per_word) { 1176 chconf = mcspi->ctx.modulctrl; 1177 chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE; 1178 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf); 1179 mcspi->ctx.modulctrl = 1180 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL); 1181 } 1182 1183 chconf = mcspi_cached_chconf0(spi); 1184 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK; 1185 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO; 1186 1187 if (t->tx_buf == NULL) 1188 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY; 1189 else if (t->rx_buf == NULL) 1190 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY; 1191 1192 if (cd && cd->turbo_mode && t->tx_buf == NULL) { 1193 /* Turbo mode is for more than one word */ 1194 if (t->len > ((cs->word_len + 7) >> 3)) 1195 chconf |= OMAP2_MCSPI_CHCONF_TURBO; 1196 } 1197 1198 mcspi_write_chconf0(spi, chconf); 1199 1200 if (t->len) { 1201 unsigned count; 1202 1203 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) && 1204 master->cur_msg_mapped && 1205 master->can_dma(master, spi, t)) 1206 omap2_mcspi_set_fifo(spi, t, 1); 1207 1208 omap2_mcspi_set_enable(spi, 1); 1209 1210 /* RX_ONLY mode needs dummy data in TX reg */ 1211 if (t->tx_buf == NULL) 1212 writel_relaxed(0, cs->base 1213 + OMAP2_MCSPI_TX0); 1214 1215 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) && 1216 master->cur_msg_mapped && 1217 master->can_dma(master, spi, t)) 1218 count = omap2_mcspi_txrx_dma(spi, t); 1219 else 1220 count = omap2_mcspi_txrx_pio(spi, t); 1221 1222 if (count != t->len) { 1223 status = -EIO; 1224 goto out; 1225 } 1226 } 1227 1228 omap2_mcspi_set_enable(spi, 0); 1229 1230 if (mcspi->fifo_depth > 0) 1231 omap2_mcspi_set_fifo(spi, t, 0); 1232 1233 out: 1234 /* Restore defaults if they were overriden */ 1235 if (par_override) { 1236 par_override = 0; 1237 status = omap2_mcspi_setup_transfer(spi, NULL); 1238 } 1239 1240 if (cd && cd->cs_per_word) { 1241 chconf = mcspi->ctx.modulctrl; 1242 chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE; 1243 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf); 1244 mcspi->ctx.modulctrl = 1245 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL); 1246 } 1247 1248 omap2_mcspi_set_enable(spi, 0); 1249 1250 if (spi->cs_gpiod) 1251 omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH)); 1252 1253 if (mcspi->fifo_depth > 0 && t) 1254 omap2_mcspi_set_fifo(spi, t, 0); 1255 1256 return status; 1257 } 1258 1259 static int omap2_mcspi_prepare_message(struct spi_master *master, 1260 struct spi_message *msg) 1261 { 1262 struct omap2_mcspi *mcspi = spi_master_get_devdata(master); 1263 struct omap2_mcspi_regs *ctx = &mcspi->ctx; 1264 struct omap2_mcspi_cs *cs; 1265 1266 /* Only a single channel can have the FORCE bit enabled 1267 * in its chconf0 register. 1268 * Scan all channels and disable them except the current one. 1269 * A FORCE can remain from a last transfer having cs_change enabled 1270 */ 1271 list_for_each_entry(cs, &ctx->cs, node) { 1272 if (msg->spi->controller_state == cs) 1273 continue; 1274 1275 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) { 1276 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE; 1277 writel_relaxed(cs->chconf0, 1278 cs->base + OMAP2_MCSPI_CHCONF0); 1279 readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0); 1280 } 1281 } 1282 1283 return 0; 1284 } 1285 1286 static bool omap2_mcspi_can_dma(struct spi_master *master, 1287 struct spi_device *spi, 1288 struct spi_transfer *xfer) 1289 { 1290 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master); 1291 struct omap2_mcspi_dma *mcspi_dma = 1292 &mcspi->dma_channels[spi->chip_select]; 1293 1294 if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) 1295 return false; 1296 1297 if (spi_controller_is_slave(master)) 1298 return true; 1299 1300 master->dma_rx = mcspi_dma->dma_rx; 1301 master->dma_tx = mcspi_dma->dma_tx; 1302 1303 return (xfer->len >= DMA_MIN_BYTES); 1304 } 1305 1306 static size_t omap2_mcspi_max_xfer_size(struct spi_device *spi) 1307 { 1308 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master); 1309 struct omap2_mcspi_dma *mcspi_dma = 1310 &mcspi->dma_channels[spi->chip_select]; 1311 1312 if (mcspi->max_xfer_len && mcspi_dma->dma_rx) 1313 return mcspi->max_xfer_len; 1314 1315 return SIZE_MAX; 1316 } 1317 1318 static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi) 1319 { 1320 struct spi_master *master = mcspi->master; 1321 struct omap2_mcspi_regs *ctx = &mcspi->ctx; 1322 int ret = 0; 1323 1324 ret = pm_runtime_resume_and_get(mcspi->dev); 1325 if (ret < 0) 1326 return ret; 1327 1328 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, 1329 OMAP2_MCSPI_WAKEUPENABLE_WKEN); 1330 ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN; 1331 1332 omap2_mcspi_set_mode(master); 1333 pm_runtime_mark_last_busy(mcspi->dev); 1334 pm_runtime_put_autosuspend(mcspi->dev); 1335 return 0; 1336 } 1337 1338 static int omap_mcspi_runtime_suspend(struct device *dev) 1339 { 1340 int error; 1341 1342 error = pinctrl_pm_select_idle_state(dev); 1343 if (error) 1344 dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error); 1345 1346 return 0; 1347 } 1348 1349 /* 1350 * When SPI wake up from off-mode, CS is in activate state. If it was in 1351 * inactive state when driver was suspend, then force it to inactive state at 1352 * wake up. 1353 */ 1354 static int omap_mcspi_runtime_resume(struct device *dev) 1355 { 1356 struct spi_master *master = dev_get_drvdata(dev); 1357 struct omap2_mcspi *mcspi = spi_master_get_devdata(master); 1358 struct omap2_mcspi_regs *ctx = &mcspi->ctx; 1359 struct omap2_mcspi_cs *cs; 1360 int error; 1361 1362 error = pinctrl_pm_select_default_state(dev); 1363 if (error) 1364 dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error); 1365 1366 /* McSPI: context restore */ 1367 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl); 1368 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable); 1369 1370 list_for_each_entry(cs, &ctx->cs, node) { 1371 /* 1372 * We need to toggle CS state for OMAP take this 1373 * change in account. 1374 */ 1375 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) { 1376 cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE; 1377 writel_relaxed(cs->chconf0, 1378 cs->base + OMAP2_MCSPI_CHCONF0); 1379 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE; 1380 writel_relaxed(cs->chconf0, 1381 cs->base + OMAP2_MCSPI_CHCONF0); 1382 } else { 1383 writel_relaxed(cs->chconf0, 1384 cs->base + OMAP2_MCSPI_CHCONF0); 1385 } 1386 } 1387 1388 return 0; 1389 } 1390 1391 static struct omap2_mcspi_platform_config omap2_pdata = { 1392 .regs_offset = 0, 1393 }; 1394 1395 static struct omap2_mcspi_platform_config omap4_pdata = { 1396 .regs_offset = OMAP4_MCSPI_REG_OFFSET, 1397 }; 1398 1399 static struct omap2_mcspi_platform_config am654_pdata = { 1400 .regs_offset = OMAP4_MCSPI_REG_OFFSET, 1401 .max_xfer_len = SZ_4K - 1, 1402 }; 1403 1404 static const struct of_device_id omap_mcspi_of_match[] = { 1405 { 1406 .compatible = "ti,omap2-mcspi", 1407 .data = &omap2_pdata, 1408 }, 1409 { 1410 .compatible = "ti,omap4-mcspi", 1411 .data = &omap4_pdata, 1412 }, 1413 { 1414 .compatible = "ti,am654-mcspi", 1415 .data = &am654_pdata, 1416 }, 1417 { }, 1418 }; 1419 MODULE_DEVICE_TABLE(of, omap_mcspi_of_match); 1420 1421 static int omap2_mcspi_probe(struct platform_device *pdev) 1422 { 1423 struct spi_master *master; 1424 const struct omap2_mcspi_platform_config *pdata; 1425 struct omap2_mcspi *mcspi; 1426 struct resource *r; 1427 int status = 0, i; 1428 u32 regs_offset = 0; 1429 struct device_node *node = pdev->dev.of_node; 1430 const struct of_device_id *match; 1431 1432 if (of_property_read_bool(node, "spi-slave")) 1433 master = spi_alloc_slave(&pdev->dev, sizeof(*mcspi)); 1434 else 1435 master = spi_alloc_master(&pdev->dev, sizeof(*mcspi)); 1436 if (!master) 1437 return -ENOMEM; 1438 1439 /* the spi->mode bits understood by this driver: */ 1440 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; 1441 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); 1442 master->setup = omap2_mcspi_setup; 1443 master->auto_runtime_pm = true; 1444 master->prepare_message = omap2_mcspi_prepare_message; 1445 master->can_dma = omap2_mcspi_can_dma; 1446 master->transfer_one = omap2_mcspi_transfer_one; 1447 master->set_cs = omap2_mcspi_set_cs; 1448 master->cleanup = omap2_mcspi_cleanup; 1449 master->slave_abort = omap2_mcspi_slave_abort; 1450 master->dev.of_node = node; 1451 master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ; 1452 master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15; 1453 master->use_gpio_descriptors = true; 1454 1455 platform_set_drvdata(pdev, master); 1456 1457 mcspi = spi_master_get_devdata(master); 1458 mcspi->master = master; 1459 1460 match = of_match_device(omap_mcspi_of_match, &pdev->dev); 1461 if (match) { 1462 u32 num_cs = 1; /* default number of chipselect */ 1463 pdata = match->data; 1464 1465 of_property_read_u32(node, "ti,spi-num-cs", &num_cs); 1466 master->num_chipselect = num_cs; 1467 if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL)) 1468 mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN; 1469 } else { 1470 pdata = dev_get_platdata(&pdev->dev); 1471 master->num_chipselect = pdata->num_cs; 1472 mcspi->pin_dir = pdata->pin_dir; 1473 } 1474 regs_offset = pdata->regs_offset; 1475 if (pdata->max_xfer_len) { 1476 mcspi->max_xfer_len = pdata->max_xfer_len; 1477 master->max_transfer_size = omap2_mcspi_max_xfer_size; 1478 } 1479 1480 r = platform_get_resource(pdev, IORESOURCE_MEM, 0); 1481 mcspi->base = devm_ioremap_resource(&pdev->dev, r); 1482 if (IS_ERR(mcspi->base)) { 1483 status = PTR_ERR(mcspi->base); 1484 goto free_master; 1485 } 1486 mcspi->phys = r->start + regs_offset; 1487 mcspi->base += regs_offset; 1488 1489 mcspi->dev = &pdev->dev; 1490 1491 INIT_LIST_HEAD(&mcspi->ctx.cs); 1492 1493 mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect, 1494 sizeof(struct omap2_mcspi_dma), 1495 GFP_KERNEL); 1496 if (mcspi->dma_channels == NULL) { 1497 status = -ENOMEM; 1498 goto free_master; 1499 } 1500 1501 for (i = 0; i < master->num_chipselect; i++) { 1502 sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i); 1503 sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i); 1504 1505 status = omap2_mcspi_request_dma(mcspi, 1506 &mcspi->dma_channels[i]); 1507 if (status == -EPROBE_DEFER) 1508 goto free_master; 1509 } 1510 1511 status = platform_get_irq(pdev, 0); 1512 if (status == -EPROBE_DEFER) 1513 goto free_master; 1514 if (status < 0) { 1515 dev_err(&pdev->dev, "no irq resource found\n"); 1516 goto free_master; 1517 } 1518 init_completion(&mcspi->txdone); 1519 status = devm_request_irq(&pdev->dev, status, 1520 omap2_mcspi_irq_handler, 0, pdev->name, 1521 mcspi); 1522 if (status) { 1523 dev_err(&pdev->dev, "Cannot request IRQ"); 1524 goto free_master; 1525 } 1526 1527 pm_runtime_use_autosuspend(&pdev->dev); 1528 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT); 1529 pm_runtime_enable(&pdev->dev); 1530 1531 status = omap2_mcspi_controller_setup(mcspi); 1532 if (status < 0) 1533 goto disable_pm; 1534 1535 status = devm_spi_register_controller(&pdev->dev, master); 1536 if (status < 0) 1537 goto disable_pm; 1538 1539 return status; 1540 1541 disable_pm: 1542 pm_runtime_dont_use_autosuspend(&pdev->dev); 1543 pm_runtime_put_sync(&pdev->dev); 1544 pm_runtime_disable(&pdev->dev); 1545 free_master: 1546 omap2_mcspi_release_dma(master); 1547 spi_master_put(master); 1548 return status; 1549 } 1550 1551 static int omap2_mcspi_remove(struct platform_device *pdev) 1552 { 1553 struct spi_master *master = platform_get_drvdata(pdev); 1554 struct omap2_mcspi *mcspi = spi_master_get_devdata(master); 1555 1556 omap2_mcspi_release_dma(master); 1557 1558 pm_runtime_dont_use_autosuspend(mcspi->dev); 1559 pm_runtime_put_sync(mcspi->dev); 1560 pm_runtime_disable(&pdev->dev); 1561 1562 return 0; 1563 } 1564 1565 /* work with hotplug and coldplug */ 1566 MODULE_ALIAS("platform:omap2_mcspi"); 1567 1568 static int __maybe_unused omap2_mcspi_suspend(struct device *dev) 1569 { 1570 struct spi_master *master = dev_get_drvdata(dev); 1571 struct omap2_mcspi *mcspi = spi_master_get_devdata(master); 1572 int error; 1573 1574 error = pinctrl_pm_select_sleep_state(dev); 1575 if (error) 1576 dev_warn(mcspi->dev, "%s: failed to set pins: %i\n", 1577 __func__, error); 1578 1579 error = spi_master_suspend(master); 1580 if (error) 1581 dev_warn(mcspi->dev, "%s: master suspend failed: %i\n", 1582 __func__, error); 1583 1584 return pm_runtime_force_suspend(dev); 1585 } 1586 1587 static int __maybe_unused omap2_mcspi_resume(struct device *dev) 1588 { 1589 struct spi_master *master = dev_get_drvdata(dev); 1590 struct omap2_mcspi *mcspi = spi_master_get_devdata(master); 1591 int error; 1592 1593 error = spi_master_resume(master); 1594 if (error) 1595 dev_warn(mcspi->dev, "%s: master resume failed: %i\n", 1596 __func__, error); 1597 1598 return pm_runtime_force_resume(dev); 1599 } 1600 1601 static const struct dev_pm_ops omap2_mcspi_pm_ops = { 1602 SET_SYSTEM_SLEEP_PM_OPS(omap2_mcspi_suspend, 1603 omap2_mcspi_resume) 1604 .runtime_suspend = omap_mcspi_runtime_suspend, 1605 .runtime_resume = omap_mcspi_runtime_resume, 1606 }; 1607 1608 static struct platform_driver omap2_mcspi_driver = { 1609 .driver = { 1610 .name = "omap2_mcspi", 1611 .pm = &omap2_mcspi_pm_ops, 1612 .of_match_table = omap_mcspi_of_match, 1613 }, 1614 .probe = omap2_mcspi_probe, 1615 .remove = omap2_mcspi_remove, 1616 }; 1617 1618 module_platform_driver(omap2_mcspi_driver); 1619 MODULE_LICENSE("GPL"); 1620