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_controller *ctlr; 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 struct clk *ref_clk; 129 int fifo_depth; 130 bool target_aborted; 131 unsigned int pin_dir:1; 132 size_t max_xfer_len; 133 u32 ref_clk_hz; 134 bool use_multi_mode; 135 }; 136 137 struct omap2_mcspi_cs { 138 void __iomem *base; 139 unsigned long phys; 140 int word_len; 141 u16 mode; 142 struct list_head node; 143 /* Context save and restore shadow register */ 144 u32 chconf0, chctrl0; 145 }; 146 147 static inline void mcspi_write_reg(struct spi_controller *ctlr, 148 int idx, u32 val) 149 { 150 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr); 151 152 writel_relaxed(val, mcspi->base + idx); 153 } 154 155 static inline u32 mcspi_read_reg(struct spi_controller *ctlr, int idx) 156 { 157 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr); 158 159 return readl_relaxed(mcspi->base + idx); 160 } 161 162 static inline void mcspi_write_cs_reg(const struct spi_device *spi, 163 int idx, u32 val) 164 { 165 struct omap2_mcspi_cs *cs = spi->controller_state; 166 167 writel_relaxed(val, cs->base + idx); 168 } 169 170 static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx) 171 { 172 struct omap2_mcspi_cs *cs = spi->controller_state; 173 174 return readl_relaxed(cs->base + idx); 175 } 176 177 static inline u32 mcspi_cached_chconf0(const struct spi_device *spi) 178 { 179 struct omap2_mcspi_cs *cs = spi->controller_state; 180 181 return cs->chconf0; 182 } 183 184 static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val) 185 { 186 struct omap2_mcspi_cs *cs = spi->controller_state; 187 188 cs->chconf0 = val; 189 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val); 190 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0); 191 } 192 193 static inline int mcspi_bytes_per_word(int word_len) 194 { 195 if (word_len <= 8) 196 return 1; 197 else if (word_len <= 16) 198 return 2; 199 else /* word_len <= 32 */ 200 return 4; 201 } 202 203 static void omap2_mcspi_set_dma_req(const struct spi_device *spi, 204 int is_read, int enable) 205 { 206 u32 l, rw; 207 208 l = mcspi_cached_chconf0(spi); 209 210 if (is_read) /* 1 is read, 0 write */ 211 rw = OMAP2_MCSPI_CHCONF_DMAR; 212 else 213 rw = OMAP2_MCSPI_CHCONF_DMAW; 214 215 if (enable) 216 l |= rw; 217 else 218 l &= ~rw; 219 220 mcspi_write_chconf0(spi, l); 221 } 222 223 static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable) 224 { 225 struct omap2_mcspi_cs *cs = spi->controller_state; 226 u32 l; 227 228 l = cs->chctrl0; 229 if (enable) 230 l |= OMAP2_MCSPI_CHCTRL_EN; 231 else 232 l &= ~OMAP2_MCSPI_CHCTRL_EN; 233 cs->chctrl0 = l; 234 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0); 235 /* Flash post-writes */ 236 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0); 237 } 238 239 static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable) 240 { 241 struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller); 242 u32 l; 243 244 /* The controller handles the inverted chip selects 245 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert 246 * the inversion from the core spi_set_cs function. 247 */ 248 if (spi->mode & SPI_CS_HIGH) 249 enable = !enable; 250 251 if (spi->controller_state) { 252 int err = pm_runtime_resume_and_get(mcspi->dev); 253 if (err < 0) { 254 dev_err(mcspi->dev, "failed to get sync: %d\n", err); 255 return; 256 } 257 258 l = mcspi_cached_chconf0(spi); 259 260 /* Only enable chip select manually if single mode is used */ 261 if (mcspi->use_multi_mode) { 262 l &= ~OMAP2_MCSPI_CHCONF_FORCE; 263 } else { 264 if (enable) 265 l &= ~OMAP2_MCSPI_CHCONF_FORCE; 266 else 267 l |= OMAP2_MCSPI_CHCONF_FORCE; 268 } 269 270 mcspi_write_chconf0(spi, l); 271 272 pm_runtime_mark_last_busy(mcspi->dev); 273 pm_runtime_put_autosuspend(mcspi->dev); 274 } 275 } 276 277 static void omap2_mcspi_set_mode(struct spi_controller *ctlr) 278 { 279 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr); 280 struct omap2_mcspi_regs *ctx = &mcspi->ctx; 281 u32 l; 282 283 /* 284 * Choose host or target mode 285 */ 286 l = mcspi_read_reg(ctlr, OMAP2_MCSPI_MODULCTRL); 287 l &= ~(OMAP2_MCSPI_MODULCTRL_STEST); 288 if (spi_controller_is_target(ctlr)) { 289 l |= (OMAP2_MCSPI_MODULCTRL_MS); 290 } else { 291 l &= ~(OMAP2_MCSPI_MODULCTRL_MS); 292 293 /* Enable single mode if needed */ 294 if (mcspi->use_multi_mode) 295 l &= ~OMAP2_MCSPI_MODULCTRL_SINGLE; 296 else 297 l |= OMAP2_MCSPI_MODULCTRL_SINGLE; 298 } 299 mcspi_write_reg(ctlr, OMAP2_MCSPI_MODULCTRL, l); 300 301 ctx->modulctrl = l; 302 } 303 304 static void omap2_mcspi_set_fifo(const struct spi_device *spi, 305 struct spi_transfer *t, int enable) 306 { 307 struct spi_controller *ctlr = spi->controller; 308 struct omap2_mcspi_cs *cs = spi->controller_state; 309 struct omap2_mcspi *mcspi; 310 unsigned int wcnt; 311 int max_fifo_depth, bytes_per_word; 312 u32 chconf, xferlevel; 313 314 mcspi = spi_controller_get_devdata(ctlr); 315 316 chconf = mcspi_cached_chconf0(spi); 317 if (enable) { 318 bytes_per_word = mcspi_bytes_per_word(cs->word_len); 319 if (t->len % bytes_per_word != 0) 320 goto disable_fifo; 321 322 if (t->rx_buf != NULL && t->tx_buf != NULL) 323 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2; 324 else 325 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH; 326 327 wcnt = t->len / bytes_per_word; 328 if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT) 329 goto disable_fifo; 330 331 xferlevel = wcnt << 16; 332 if (t->rx_buf != NULL) { 333 chconf |= OMAP2_MCSPI_CHCONF_FFER; 334 xferlevel |= (bytes_per_word - 1) << 8; 335 } 336 337 if (t->tx_buf != NULL) { 338 chconf |= OMAP2_MCSPI_CHCONF_FFET; 339 xferlevel |= bytes_per_word - 1; 340 } 341 342 mcspi_write_reg(ctlr, OMAP2_MCSPI_XFERLEVEL, xferlevel); 343 mcspi_write_chconf0(spi, chconf); 344 mcspi->fifo_depth = max_fifo_depth; 345 346 return; 347 } 348 349 disable_fifo: 350 if (t->rx_buf != NULL) 351 chconf &= ~OMAP2_MCSPI_CHCONF_FFER; 352 353 if (t->tx_buf != NULL) 354 chconf &= ~OMAP2_MCSPI_CHCONF_FFET; 355 356 mcspi_write_chconf0(spi, chconf); 357 mcspi->fifo_depth = 0; 358 } 359 360 static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit) 361 { 362 unsigned long timeout; 363 364 timeout = jiffies + msecs_to_jiffies(1000); 365 while (!(readl_relaxed(reg) & bit)) { 366 if (time_after(jiffies, timeout)) { 367 if (!(readl_relaxed(reg) & bit)) 368 return -ETIMEDOUT; 369 else 370 return 0; 371 } 372 cpu_relax(); 373 } 374 return 0; 375 } 376 377 static int mcspi_wait_for_completion(struct omap2_mcspi *mcspi, 378 struct completion *x) 379 { 380 if (spi_controller_is_target(mcspi->ctlr)) { 381 if (wait_for_completion_interruptible(x) || 382 mcspi->target_aborted) 383 return -EINTR; 384 } else { 385 wait_for_completion(x); 386 } 387 388 return 0; 389 } 390 391 static void omap2_mcspi_rx_callback(void *data) 392 { 393 struct spi_device *spi = data; 394 struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller); 395 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)]; 396 397 /* We must disable the DMA RX request */ 398 omap2_mcspi_set_dma_req(spi, 1, 0); 399 400 complete(&mcspi_dma->dma_rx_completion); 401 } 402 403 static void omap2_mcspi_tx_callback(void *data) 404 { 405 struct spi_device *spi = data; 406 struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller); 407 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)]; 408 409 /* We must disable the DMA TX request */ 410 omap2_mcspi_set_dma_req(spi, 0, 0); 411 412 complete(&mcspi_dma->dma_tx_completion); 413 } 414 415 static void omap2_mcspi_tx_dma(struct spi_device *spi, 416 struct spi_transfer *xfer, 417 struct dma_slave_config cfg) 418 { 419 struct omap2_mcspi *mcspi; 420 struct omap2_mcspi_dma *mcspi_dma; 421 struct dma_async_tx_descriptor *tx; 422 423 mcspi = spi_controller_get_devdata(spi->controller); 424 mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)]; 425 426 dmaengine_slave_config(mcspi_dma->dma_tx, &cfg); 427 428 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl, 429 xfer->tx_sg.nents, 430 DMA_MEM_TO_DEV, 431 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 432 if (tx) { 433 tx->callback = omap2_mcspi_tx_callback; 434 tx->callback_param = spi; 435 dmaengine_submit(tx); 436 } else { 437 /* FIXME: fall back to PIO? */ 438 } 439 dma_async_issue_pending(mcspi_dma->dma_tx); 440 omap2_mcspi_set_dma_req(spi, 0, 1); 441 } 442 443 static unsigned 444 omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer, 445 struct dma_slave_config cfg, 446 unsigned es) 447 { 448 struct omap2_mcspi *mcspi; 449 struct omap2_mcspi_dma *mcspi_dma; 450 unsigned int count, transfer_reduction = 0; 451 struct scatterlist *sg_out[2]; 452 int nb_sizes = 0, out_mapped_nents[2], ret, x; 453 size_t sizes[2]; 454 u32 l; 455 int elements = 0; 456 int word_len, element_count; 457 struct omap2_mcspi_cs *cs = spi->controller_state; 458 void __iomem *chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0; 459 struct dma_async_tx_descriptor *tx; 460 461 mcspi = spi_controller_get_devdata(spi->controller); 462 mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)]; 463 count = xfer->len; 464 465 /* 466 * In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM 467 * it mentions reducing DMA transfer length by one element in host 468 * normal mode. 469 */ 470 if (mcspi->fifo_depth == 0) 471 transfer_reduction = es; 472 473 word_len = cs->word_len; 474 l = mcspi_cached_chconf0(spi); 475 476 if (word_len <= 8) 477 element_count = count; 478 else if (word_len <= 16) 479 element_count = count >> 1; 480 else /* word_len <= 32 */ 481 element_count = count >> 2; 482 483 484 dmaengine_slave_config(mcspi_dma->dma_rx, &cfg); 485 486 /* 487 * Reduce DMA transfer length by one more if McSPI is 488 * configured in turbo mode. 489 */ 490 if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0) 491 transfer_reduction += es; 492 493 if (transfer_reduction) { 494 /* Split sgl into two. The second sgl won't be used. */ 495 sizes[0] = count - transfer_reduction; 496 sizes[1] = transfer_reduction; 497 nb_sizes = 2; 498 } else { 499 /* 500 * Don't bother splitting the sgl. This essentially 501 * clones the original sgl. 502 */ 503 sizes[0] = count; 504 nb_sizes = 1; 505 } 506 507 ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents, 0, nb_sizes, 508 sizes, sg_out, out_mapped_nents, GFP_KERNEL); 509 510 if (ret < 0) { 511 dev_err(&spi->dev, "sg_split failed\n"); 512 return 0; 513 } 514 515 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, sg_out[0], 516 out_mapped_nents[0], DMA_DEV_TO_MEM, 517 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 518 if (tx) { 519 tx->callback = omap2_mcspi_rx_callback; 520 tx->callback_param = spi; 521 dmaengine_submit(tx); 522 } else { 523 /* FIXME: fall back to PIO? */ 524 } 525 526 dma_async_issue_pending(mcspi_dma->dma_rx); 527 omap2_mcspi_set_dma_req(spi, 1, 1); 528 529 ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion); 530 if (ret || mcspi->target_aborted) { 531 dmaengine_terminate_sync(mcspi_dma->dma_rx); 532 omap2_mcspi_set_dma_req(spi, 1, 0); 533 return 0; 534 } 535 536 for (x = 0; x < nb_sizes; x++) 537 kfree(sg_out[x]); 538 539 if (mcspi->fifo_depth > 0) 540 return count; 541 542 /* 543 * Due to the DMA transfer length reduction the missing bytes must 544 * be read manually to receive all of the expected data. 545 */ 546 omap2_mcspi_set_enable(spi, 0); 547 548 elements = element_count - 1; 549 550 if (l & OMAP2_MCSPI_CHCONF_TURBO) { 551 elements--; 552 553 if (!mcspi_wait_for_reg_bit(chstat_reg, 554 OMAP2_MCSPI_CHSTAT_RXS)) { 555 u32 w; 556 557 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0); 558 if (word_len <= 8) 559 ((u8 *)xfer->rx_buf)[elements++] = w; 560 else if (word_len <= 16) 561 ((u16 *)xfer->rx_buf)[elements++] = w; 562 else /* word_len <= 32 */ 563 ((u32 *)xfer->rx_buf)[elements++] = w; 564 } else { 565 int bytes_per_word = mcspi_bytes_per_word(word_len); 566 dev_err(&spi->dev, "DMA RX penultimate word empty\n"); 567 count -= (bytes_per_word << 1); 568 omap2_mcspi_set_enable(spi, 1); 569 return count; 570 } 571 } 572 if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) { 573 u32 w; 574 575 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0); 576 if (word_len <= 8) 577 ((u8 *)xfer->rx_buf)[elements] = w; 578 else if (word_len <= 16) 579 ((u16 *)xfer->rx_buf)[elements] = w; 580 else /* word_len <= 32 */ 581 ((u32 *)xfer->rx_buf)[elements] = w; 582 } else { 583 dev_err(&spi->dev, "DMA RX last word empty\n"); 584 count -= mcspi_bytes_per_word(word_len); 585 } 586 omap2_mcspi_set_enable(spi, 1); 587 return count; 588 } 589 590 static unsigned 591 omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) 592 { 593 struct omap2_mcspi *mcspi; 594 struct omap2_mcspi_cs *cs = spi->controller_state; 595 struct omap2_mcspi_dma *mcspi_dma; 596 unsigned int count; 597 u8 *rx; 598 const u8 *tx; 599 struct dma_slave_config cfg; 600 enum dma_slave_buswidth width; 601 unsigned es; 602 void __iomem *chstat_reg; 603 void __iomem *irqstat_reg; 604 int wait_res; 605 606 mcspi = spi_controller_get_devdata(spi->controller); 607 mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)]; 608 609 if (cs->word_len <= 8) { 610 width = DMA_SLAVE_BUSWIDTH_1_BYTE; 611 es = 1; 612 } else if (cs->word_len <= 16) { 613 width = DMA_SLAVE_BUSWIDTH_2_BYTES; 614 es = 2; 615 } else { 616 width = DMA_SLAVE_BUSWIDTH_4_BYTES; 617 es = 4; 618 } 619 620 count = xfer->len; 621 622 memset(&cfg, 0, sizeof(cfg)); 623 cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0; 624 cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0; 625 cfg.src_addr_width = width; 626 cfg.dst_addr_width = width; 627 cfg.src_maxburst = 1; 628 cfg.dst_maxburst = 1; 629 630 rx = xfer->rx_buf; 631 tx = xfer->tx_buf; 632 633 mcspi->target_aborted = false; 634 reinit_completion(&mcspi_dma->dma_tx_completion); 635 reinit_completion(&mcspi_dma->dma_rx_completion); 636 reinit_completion(&mcspi->txdone); 637 if (tx) { 638 /* Enable EOW IRQ to know end of tx in target mode */ 639 if (spi_controller_is_target(spi->controller)) 640 mcspi_write_reg(spi->controller, 641 OMAP2_MCSPI_IRQENABLE, 642 OMAP2_MCSPI_IRQSTATUS_EOW); 643 omap2_mcspi_tx_dma(spi, xfer, cfg); 644 } 645 646 if (rx != NULL) 647 count = omap2_mcspi_rx_dma(spi, xfer, cfg, es); 648 649 if (tx != NULL) { 650 int ret; 651 652 ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion); 653 if (ret || mcspi->target_aborted) { 654 dmaengine_terminate_sync(mcspi_dma->dma_tx); 655 omap2_mcspi_set_dma_req(spi, 0, 0); 656 return 0; 657 } 658 659 if (spi_controller_is_target(mcspi->ctlr)) { 660 ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone); 661 if (ret || mcspi->target_aborted) 662 return 0; 663 } 664 665 if (mcspi->fifo_depth > 0) { 666 irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS; 667 668 if (mcspi_wait_for_reg_bit(irqstat_reg, 669 OMAP2_MCSPI_IRQSTATUS_EOW) < 0) 670 dev_err(&spi->dev, "EOW timed out\n"); 671 672 mcspi_write_reg(mcspi->ctlr, OMAP2_MCSPI_IRQSTATUS, 673 OMAP2_MCSPI_IRQSTATUS_EOW); 674 } 675 676 /* for TX_ONLY mode, be sure all words have shifted out */ 677 if (rx == NULL) { 678 chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0; 679 if (mcspi->fifo_depth > 0) { 680 wait_res = mcspi_wait_for_reg_bit(chstat_reg, 681 OMAP2_MCSPI_CHSTAT_TXFFE); 682 if (wait_res < 0) 683 dev_err(&spi->dev, "TXFFE timed out\n"); 684 } else { 685 wait_res = mcspi_wait_for_reg_bit(chstat_reg, 686 OMAP2_MCSPI_CHSTAT_TXS); 687 if (wait_res < 0) 688 dev_err(&spi->dev, "TXS timed out\n"); 689 } 690 if (wait_res >= 0 && 691 (mcspi_wait_for_reg_bit(chstat_reg, 692 OMAP2_MCSPI_CHSTAT_EOT) < 0)) 693 dev_err(&spi->dev, "EOT timed out\n"); 694 } 695 } 696 return count; 697 } 698 699 static unsigned 700 omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) 701 { 702 struct omap2_mcspi_cs *cs = spi->controller_state; 703 unsigned int count, c; 704 u32 l; 705 void __iomem *base = cs->base; 706 void __iomem *tx_reg; 707 void __iomem *rx_reg; 708 void __iomem *chstat_reg; 709 int word_len; 710 711 count = xfer->len; 712 c = count; 713 word_len = cs->word_len; 714 715 l = mcspi_cached_chconf0(spi); 716 717 /* We store the pre-calculated register addresses on stack to speed 718 * up the transfer loop. */ 719 tx_reg = base + OMAP2_MCSPI_TX0; 720 rx_reg = base + OMAP2_MCSPI_RX0; 721 chstat_reg = base + OMAP2_MCSPI_CHSTAT0; 722 723 if (c < (word_len>>3)) 724 return 0; 725 726 if (word_len <= 8) { 727 u8 *rx; 728 const u8 *tx; 729 730 rx = xfer->rx_buf; 731 tx = xfer->tx_buf; 732 733 do { 734 c -= 1; 735 if (tx != NULL) { 736 if (mcspi_wait_for_reg_bit(chstat_reg, 737 OMAP2_MCSPI_CHSTAT_TXS) < 0) { 738 dev_err(&spi->dev, "TXS timed out\n"); 739 goto out; 740 } 741 dev_vdbg(&spi->dev, "write-%d %02x\n", 742 word_len, *tx); 743 writel_relaxed(*tx++, tx_reg); 744 } 745 if (rx != NULL) { 746 if (mcspi_wait_for_reg_bit(chstat_reg, 747 OMAP2_MCSPI_CHSTAT_RXS) < 0) { 748 dev_err(&spi->dev, "RXS timed out\n"); 749 goto out; 750 } 751 752 if (c == 1 && tx == NULL && 753 (l & OMAP2_MCSPI_CHCONF_TURBO)) { 754 omap2_mcspi_set_enable(spi, 0); 755 *rx++ = readl_relaxed(rx_reg); 756 dev_vdbg(&spi->dev, "read-%d %02x\n", 757 word_len, *(rx - 1)); 758 if (mcspi_wait_for_reg_bit(chstat_reg, 759 OMAP2_MCSPI_CHSTAT_RXS) < 0) { 760 dev_err(&spi->dev, 761 "RXS timed out\n"); 762 goto out; 763 } 764 c = 0; 765 } else if (c == 0 && tx == NULL) { 766 omap2_mcspi_set_enable(spi, 0); 767 } 768 769 *rx++ = readl_relaxed(rx_reg); 770 dev_vdbg(&spi->dev, "read-%d %02x\n", 771 word_len, *(rx - 1)); 772 } 773 /* Add word delay between each word */ 774 spi_delay_exec(&xfer->word_delay, xfer); 775 } while (c); 776 } else if (word_len <= 16) { 777 u16 *rx; 778 const u16 *tx; 779 780 rx = xfer->rx_buf; 781 tx = xfer->tx_buf; 782 do { 783 c -= 2; 784 if (tx != NULL) { 785 if (mcspi_wait_for_reg_bit(chstat_reg, 786 OMAP2_MCSPI_CHSTAT_TXS) < 0) { 787 dev_err(&spi->dev, "TXS timed out\n"); 788 goto out; 789 } 790 dev_vdbg(&spi->dev, "write-%d %04x\n", 791 word_len, *tx); 792 writel_relaxed(*tx++, tx_reg); 793 } 794 if (rx != NULL) { 795 if (mcspi_wait_for_reg_bit(chstat_reg, 796 OMAP2_MCSPI_CHSTAT_RXS) < 0) { 797 dev_err(&spi->dev, "RXS timed out\n"); 798 goto out; 799 } 800 801 if (c == 2 && tx == NULL && 802 (l & OMAP2_MCSPI_CHCONF_TURBO)) { 803 omap2_mcspi_set_enable(spi, 0); 804 *rx++ = readl_relaxed(rx_reg); 805 dev_vdbg(&spi->dev, "read-%d %04x\n", 806 word_len, *(rx - 1)); 807 if (mcspi_wait_for_reg_bit(chstat_reg, 808 OMAP2_MCSPI_CHSTAT_RXS) < 0) { 809 dev_err(&spi->dev, 810 "RXS timed out\n"); 811 goto out; 812 } 813 c = 0; 814 } else if (c == 0 && tx == NULL) { 815 omap2_mcspi_set_enable(spi, 0); 816 } 817 818 *rx++ = readl_relaxed(rx_reg); 819 dev_vdbg(&spi->dev, "read-%d %04x\n", 820 word_len, *(rx - 1)); 821 } 822 /* Add word delay between each word */ 823 spi_delay_exec(&xfer->word_delay, xfer); 824 } while (c >= 2); 825 } else if (word_len <= 32) { 826 u32 *rx; 827 const u32 *tx; 828 829 rx = xfer->rx_buf; 830 tx = xfer->tx_buf; 831 do { 832 c -= 4; 833 if (tx != NULL) { 834 if (mcspi_wait_for_reg_bit(chstat_reg, 835 OMAP2_MCSPI_CHSTAT_TXS) < 0) { 836 dev_err(&spi->dev, "TXS timed out\n"); 837 goto out; 838 } 839 dev_vdbg(&spi->dev, "write-%d %08x\n", 840 word_len, *tx); 841 writel_relaxed(*tx++, tx_reg); 842 } 843 if (rx != NULL) { 844 if (mcspi_wait_for_reg_bit(chstat_reg, 845 OMAP2_MCSPI_CHSTAT_RXS) < 0) { 846 dev_err(&spi->dev, "RXS timed out\n"); 847 goto out; 848 } 849 850 if (c == 4 && tx == NULL && 851 (l & OMAP2_MCSPI_CHCONF_TURBO)) { 852 omap2_mcspi_set_enable(spi, 0); 853 *rx++ = readl_relaxed(rx_reg); 854 dev_vdbg(&spi->dev, "read-%d %08x\n", 855 word_len, *(rx - 1)); 856 if (mcspi_wait_for_reg_bit(chstat_reg, 857 OMAP2_MCSPI_CHSTAT_RXS) < 0) { 858 dev_err(&spi->dev, 859 "RXS timed out\n"); 860 goto out; 861 } 862 c = 0; 863 } else if (c == 0 && tx == NULL) { 864 omap2_mcspi_set_enable(spi, 0); 865 } 866 867 *rx++ = readl_relaxed(rx_reg); 868 dev_vdbg(&spi->dev, "read-%d %08x\n", 869 word_len, *(rx - 1)); 870 } 871 /* Add word delay between each word */ 872 spi_delay_exec(&xfer->word_delay, xfer); 873 } while (c >= 4); 874 } 875 876 /* for TX_ONLY mode, be sure all words have shifted out */ 877 if (xfer->rx_buf == NULL) { 878 if (mcspi_wait_for_reg_bit(chstat_reg, 879 OMAP2_MCSPI_CHSTAT_TXS) < 0) { 880 dev_err(&spi->dev, "TXS timed out\n"); 881 } else if (mcspi_wait_for_reg_bit(chstat_reg, 882 OMAP2_MCSPI_CHSTAT_EOT) < 0) 883 dev_err(&spi->dev, "EOT timed out\n"); 884 885 /* disable chan to purge rx datas received in TX_ONLY transfer, 886 * otherwise these rx datas will affect the direct following 887 * RX_ONLY transfer. 888 */ 889 omap2_mcspi_set_enable(spi, 0); 890 } 891 out: 892 omap2_mcspi_set_enable(spi, 1); 893 return count - c; 894 } 895 896 static u32 omap2_mcspi_calc_divisor(u32 speed_hz, u32 ref_clk_hz) 897 { 898 u32 div; 899 900 for (div = 0; div < 15; div++) 901 if (speed_hz >= (ref_clk_hz >> div)) 902 return div; 903 904 return 15; 905 } 906 907 /* called only when no transfer is active to this device */ 908 static int omap2_mcspi_setup_transfer(struct spi_device *spi, 909 struct spi_transfer *t) 910 { 911 struct omap2_mcspi_cs *cs = spi->controller_state; 912 struct omap2_mcspi *mcspi; 913 u32 ref_clk_hz, l = 0, clkd = 0, div, extclk = 0, clkg = 0; 914 u8 word_len = spi->bits_per_word; 915 u32 speed_hz = spi->max_speed_hz; 916 917 mcspi = spi_controller_get_devdata(spi->controller); 918 919 if (t != NULL && t->bits_per_word) 920 word_len = t->bits_per_word; 921 922 cs->word_len = word_len; 923 924 if (t && t->speed_hz) 925 speed_hz = t->speed_hz; 926 927 ref_clk_hz = mcspi->ref_clk_hz; 928 speed_hz = min_t(u32, speed_hz, ref_clk_hz); 929 if (speed_hz < (ref_clk_hz / OMAP2_MCSPI_MAX_DIVIDER)) { 930 clkd = omap2_mcspi_calc_divisor(speed_hz, ref_clk_hz); 931 speed_hz = ref_clk_hz >> clkd; 932 clkg = 0; 933 } else { 934 div = (ref_clk_hz + speed_hz - 1) / speed_hz; 935 speed_hz = ref_clk_hz / div; 936 clkd = (div - 1) & 0xf; 937 extclk = (div - 1) >> 4; 938 clkg = OMAP2_MCSPI_CHCONF_CLKG; 939 } 940 941 l = mcspi_cached_chconf0(spi); 942 943 /* standard 4-wire host mode: SCK, MOSI/out, MISO/in, nCS 944 * REVISIT: this controller could support SPI_3WIRE mode. 945 */ 946 if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) { 947 l &= ~OMAP2_MCSPI_CHCONF_IS; 948 l &= ~OMAP2_MCSPI_CHCONF_DPE1; 949 l |= OMAP2_MCSPI_CHCONF_DPE0; 950 } else { 951 l |= OMAP2_MCSPI_CHCONF_IS; 952 l |= OMAP2_MCSPI_CHCONF_DPE1; 953 l &= ~OMAP2_MCSPI_CHCONF_DPE0; 954 } 955 956 /* wordlength */ 957 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK; 958 l |= (word_len - 1) << 7; 959 960 /* set chipselect polarity; manage with FORCE */ 961 if (!(spi->mode & SPI_CS_HIGH)) 962 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */ 963 else 964 l &= ~OMAP2_MCSPI_CHCONF_EPOL; 965 966 /* set clock divisor */ 967 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK; 968 l |= clkd << 2; 969 970 /* set clock granularity */ 971 l &= ~OMAP2_MCSPI_CHCONF_CLKG; 972 l |= clkg; 973 if (clkg) { 974 cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK; 975 cs->chctrl0 |= extclk << 8; 976 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0); 977 } 978 979 /* set SPI mode 0..3 */ 980 if (spi->mode & SPI_CPOL) 981 l |= OMAP2_MCSPI_CHCONF_POL; 982 else 983 l &= ~OMAP2_MCSPI_CHCONF_POL; 984 if (spi->mode & SPI_CPHA) 985 l |= OMAP2_MCSPI_CHCONF_PHA; 986 else 987 l &= ~OMAP2_MCSPI_CHCONF_PHA; 988 989 mcspi_write_chconf0(spi, l); 990 991 cs->mode = spi->mode; 992 993 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n", 994 speed_hz, 995 (spi->mode & SPI_CPHA) ? "trailing" : "leading", 996 (spi->mode & SPI_CPOL) ? "inverted" : "normal"); 997 998 return 0; 999 } 1000 1001 /* 1002 * Note that we currently allow DMA only if we get a channel 1003 * for both rx and tx. Otherwise we'll do PIO for both rx and tx. 1004 */ 1005 static int omap2_mcspi_request_dma(struct omap2_mcspi *mcspi, 1006 struct omap2_mcspi_dma *mcspi_dma) 1007 { 1008 int ret = 0; 1009 1010 mcspi_dma->dma_rx = dma_request_chan(mcspi->dev, 1011 mcspi_dma->dma_rx_ch_name); 1012 if (IS_ERR(mcspi_dma->dma_rx)) { 1013 ret = PTR_ERR(mcspi_dma->dma_rx); 1014 mcspi_dma->dma_rx = NULL; 1015 goto no_dma; 1016 } 1017 1018 mcspi_dma->dma_tx = dma_request_chan(mcspi->dev, 1019 mcspi_dma->dma_tx_ch_name); 1020 if (IS_ERR(mcspi_dma->dma_tx)) { 1021 ret = PTR_ERR(mcspi_dma->dma_tx); 1022 mcspi_dma->dma_tx = NULL; 1023 dma_release_channel(mcspi_dma->dma_rx); 1024 mcspi_dma->dma_rx = NULL; 1025 } 1026 1027 init_completion(&mcspi_dma->dma_rx_completion); 1028 init_completion(&mcspi_dma->dma_tx_completion); 1029 1030 no_dma: 1031 return ret; 1032 } 1033 1034 static void omap2_mcspi_release_dma(struct spi_controller *ctlr) 1035 { 1036 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr); 1037 struct omap2_mcspi_dma *mcspi_dma; 1038 int i; 1039 1040 for (i = 0; i < ctlr->num_chipselect; i++) { 1041 mcspi_dma = &mcspi->dma_channels[i]; 1042 1043 if (mcspi_dma->dma_rx) { 1044 dma_release_channel(mcspi_dma->dma_rx); 1045 mcspi_dma->dma_rx = NULL; 1046 } 1047 if (mcspi_dma->dma_tx) { 1048 dma_release_channel(mcspi_dma->dma_tx); 1049 mcspi_dma->dma_tx = NULL; 1050 } 1051 } 1052 } 1053 1054 static void omap2_mcspi_cleanup(struct spi_device *spi) 1055 { 1056 struct omap2_mcspi_cs *cs; 1057 1058 if (spi->controller_state) { 1059 /* Unlink controller state from context save list */ 1060 cs = spi->controller_state; 1061 list_del(&cs->node); 1062 1063 kfree(cs); 1064 } 1065 } 1066 1067 static int omap2_mcspi_setup(struct spi_device *spi) 1068 { 1069 bool initial_setup = false; 1070 int ret; 1071 struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller); 1072 struct omap2_mcspi_regs *ctx = &mcspi->ctx; 1073 struct omap2_mcspi_cs *cs = spi->controller_state; 1074 1075 if (!cs) { 1076 cs = kzalloc(sizeof(*cs), GFP_KERNEL); 1077 if (!cs) 1078 return -ENOMEM; 1079 cs->base = mcspi->base + spi_get_chipselect(spi, 0) * 0x14; 1080 cs->phys = mcspi->phys + spi_get_chipselect(spi, 0) * 0x14; 1081 cs->mode = 0; 1082 cs->chconf0 = 0; 1083 cs->chctrl0 = 0; 1084 spi->controller_state = cs; 1085 /* Link this to context save list */ 1086 list_add_tail(&cs->node, &ctx->cs); 1087 initial_setup = true; 1088 } 1089 1090 ret = pm_runtime_resume_and_get(mcspi->dev); 1091 if (ret < 0) { 1092 if (initial_setup) 1093 omap2_mcspi_cleanup(spi); 1094 1095 return ret; 1096 } 1097 1098 ret = omap2_mcspi_setup_transfer(spi, NULL); 1099 if (ret && initial_setup) 1100 omap2_mcspi_cleanup(spi); 1101 1102 pm_runtime_mark_last_busy(mcspi->dev); 1103 pm_runtime_put_autosuspend(mcspi->dev); 1104 1105 return ret; 1106 } 1107 1108 static irqreturn_t omap2_mcspi_irq_handler(int irq, void *data) 1109 { 1110 struct omap2_mcspi *mcspi = data; 1111 u32 irqstat; 1112 1113 irqstat = mcspi_read_reg(mcspi->ctlr, OMAP2_MCSPI_IRQSTATUS); 1114 if (!irqstat) 1115 return IRQ_NONE; 1116 1117 /* Disable IRQ and wakeup target xfer task */ 1118 mcspi_write_reg(mcspi->ctlr, OMAP2_MCSPI_IRQENABLE, 0); 1119 if (irqstat & OMAP2_MCSPI_IRQSTATUS_EOW) 1120 complete(&mcspi->txdone); 1121 1122 return IRQ_HANDLED; 1123 } 1124 1125 static int omap2_mcspi_target_abort(struct spi_controller *ctlr) 1126 { 1127 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr); 1128 struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels; 1129 1130 mcspi->target_aborted = true; 1131 complete(&mcspi_dma->dma_rx_completion); 1132 complete(&mcspi_dma->dma_tx_completion); 1133 complete(&mcspi->txdone); 1134 1135 return 0; 1136 } 1137 1138 static int omap2_mcspi_transfer_one(struct spi_controller *ctlr, 1139 struct spi_device *spi, 1140 struct spi_transfer *t) 1141 { 1142 1143 /* We only enable one channel at a time -- the one whose message is 1144 * -- although this controller would gladly 1145 * arbitrate among multiple channels. This corresponds to "single 1146 * channel" host mode. As a side effect, we need to manage the 1147 * chipselect with the FORCE bit ... CS != channel enable. 1148 */ 1149 1150 struct omap2_mcspi *mcspi; 1151 struct omap2_mcspi_dma *mcspi_dma; 1152 struct omap2_mcspi_cs *cs; 1153 struct omap2_mcspi_device_config *cd; 1154 int par_override = 0; 1155 int status = 0; 1156 u32 chconf; 1157 1158 mcspi = spi_controller_get_devdata(ctlr); 1159 mcspi_dma = mcspi->dma_channels + spi_get_chipselect(spi, 0); 1160 cs = spi->controller_state; 1161 cd = spi->controller_data; 1162 1163 /* 1164 * The target driver could have changed spi->mode in which case 1165 * it will be different from cs->mode (the current hardware setup). 1166 * If so, set par_override (even though its not a parity issue) so 1167 * omap2_mcspi_setup_transfer will be called to configure the hardware 1168 * with the correct mode on the first iteration of the loop below. 1169 */ 1170 if (spi->mode != cs->mode) 1171 par_override = 1; 1172 1173 omap2_mcspi_set_enable(spi, 0); 1174 1175 if (spi_get_csgpiod(spi, 0)) 1176 omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH); 1177 1178 if (par_override || 1179 (t->speed_hz != spi->max_speed_hz) || 1180 (t->bits_per_word != spi->bits_per_word)) { 1181 par_override = 1; 1182 status = omap2_mcspi_setup_transfer(spi, t); 1183 if (status < 0) 1184 goto out; 1185 if (t->speed_hz == spi->max_speed_hz && 1186 t->bits_per_word == spi->bits_per_word) 1187 par_override = 0; 1188 } 1189 1190 chconf = mcspi_cached_chconf0(spi); 1191 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK; 1192 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO; 1193 1194 if (t->tx_buf == NULL) 1195 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY; 1196 else if (t->rx_buf == NULL) 1197 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY; 1198 1199 if (cd && cd->turbo_mode && t->tx_buf == NULL) { 1200 /* Turbo mode is for more than one word */ 1201 if (t->len > ((cs->word_len + 7) >> 3)) 1202 chconf |= OMAP2_MCSPI_CHCONF_TURBO; 1203 } 1204 1205 mcspi_write_chconf0(spi, chconf); 1206 1207 if (t->len) { 1208 unsigned count; 1209 1210 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) && 1211 ctlr->cur_msg_mapped && 1212 ctlr->can_dma(ctlr, spi, t)) 1213 omap2_mcspi_set_fifo(spi, t, 1); 1214 1215 omap2_mcspi_set_enable(spi, 1); 1216 1217 /* RX_ONLY mode needs dummy data in TX reg */ 1218 if (t->tx_buf == NULL) 1219 writel_relaxed(0, cs->base 1220 + OMAP2_MCSPI_TX0); 1221 1222 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) && 1223 ctlr->cur_msg_mapped && 1224 ctlr->can_dma(ctlr, spi, t)) 1225 count = omap2_mcspi_txrx_dma(spi, t); 1226 else 1227 count = omap2_mcspi_txrx_pio(spi, t); 1228 1229 if (count != t->len) { 1230 status = -EIO; 1231 goto out; 1232 } 1233 } 1234 1235 omap2_mcspi_set_enable(spi, 0); 1236 1237 if (mcspi->fifo_depth > 0) 1238 omap2_mcspi_set_fifo(spi, t, 0); 1239 1240 out: 1241 /* Restore defaults if they were overriden */ 1242 if (par_override) { 1243 par_override = 0; 1244 status = omap2_mcspi_setup_transfer(spi, NULL); 1245 } 1246 1247 omap2_mcspi_set_enable(spi, 0); 1248 1249 if (spi_get_csgpiod(spi, 0)) 1250 omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH)); 1251 1252 if (mcspi->fifo_depth > 0 && t) 1253 omap2_mcspi_set_fifo(spi, t, 0); 1254 1255 return status; 1256 } 1257 1258 static int omap2_mcspi_prepare_message(struct spi_controller *ctlr, 1259 struct spi_message *msg) 1260 { 1261 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr); 1262 struct omap2_mcspi_regs *ctx = &mcspi->ctx; 1263 struct omap2_mcspi_cs *cs; 1264 struct spi_transfer *tr; 1265 u8 bits_per_word; 1266 1267 /* 1268 * The conditions are strict, it is mandatory to check each transfer of the list to see if 1269 * multi-mode is applicable. 1270 */ 1271 mcspi->use_multi_mode = true; 1272 list_for_each_entry(tr, &msg->transfers, transfer_list) { 1273 if (!tr->bits_per_word) 1274 bits_per_word = msg->spi->bits_per_word; 1275 else 1276 bits_per_word = tr->bits_per_word; 1277 1278 /* 1279 * Check if this transfer contains only one word; 1280 */ 1281 if (bits_per_word < 8 && tr->len == 1) { 1282 /* multi-mode is applicable, only one word (1..7 bits) */ 1283 } else if (bits_per_word >= 8 && tr->len == bits_per_word / 8) { 1284 /* multi-mode is applicable, only one word (8..32 bits) */ 1285 } else { 1286 /* multi-mode is not applicable: more than one word in the transfer */ 1287 mcspi->use_multi_mode = false; 1288 } 1289 1290 /* Check if transfer asks to change the CS status after the transfer */ 1291 if (!tr->cs_change) 1292 mcspi->use_multi_mode = false; 1293 1294 /* 1295 * If at least one message is not compatible, switch back to single mode 1296 * 1297 * The bits_per_word of certain transfer can be different, but it will have no 1298 * impact on the signal itself. 1299 */ 1300 if (!mcspi->use_multi_mode) 1301 break; 1302 } 1303 1304 omap2_mcspi_set_mode(ctlr); 1305 1306 /* In single mode only a single channel can have the FORCE bit enabled 1307 * in its chconf0 register. 1308 * Scan all channels and disable them except the current one. 1309 * A FORCE can remain from a last transfer having cs_change enabled 1310 * 1311 * In multi mode all FORCE bits must be disabled. 1312 */ 1313 list_for_each_entry(cs, &ctx->cs, node) { 1314 if (msg->spi->controller_state == cs && !mcspi->use_multi_mode) { 1315 continue; 1316 } 1317 1318 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) { 1319 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE; 1320 writel_relaxed(cs->chconf0, 1321 cs->base + OMAP2_MCSPI_CHCONF0); 1322 readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0); 1323 } 1324 } 1325 1326 return 0; 1327 } 1328 1329 static bool omap2_mcspi_can_dma(struct spi_controller *ctlr, 1330 struct spi_device *spi, 1331 struct spi_transfer *xfer) 1332 { 1333 struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller); 1334 struct omap2_mcspi_dma *mcspi_dma = 1335 &mcspi->dma_channels[spi_get_chipselect(spi, 0)]; 1336 1337 if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) 1338 return false; 1339 1340 if (spi_controller_is_target(ctlr)) 1341 return true; 1342 1343 ctlr->dma_rx = mcspi_dma->dma_rx; 1344 ctlr->dma_tx = mcspi_dma->dma_tx; 1345 1346 return (xfer->len >= DMA_MIN_BYTES); 1347 } 1348 1349 static size_t omap2_mcspi_max_xfer_size(struct spi_device *spi) 1350 { 1351 struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller); 1352 struct omap2_mcspi_dma *mcspi_dma = 1353 &mcspi->dma_channels[spi_get_chipselect(spi, 0)]; 1354 1355 if (mcspi->max_xfer_len && mcspi_dma->dma_rx) 1356 return mcspi->max_xfer_len; 1357 1358 return SIZE_MAX; 1359 } 1360 1361 static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi) 1362 { 1363 struct spi_controller *ctlr = mcspi->ctlr; 1364 struct omap2_mcspi_regs *ctx = &mcspi->ctx; 1365 int ret = 0; 1366 1367 ret = pm_runtime_resume_and_get(mcspi->dev); 1368 if (ret < 0) 1369 return ret; 1370 1371 mcspi_write_reg(ctlr, OMAP2_MCSPI_WAKEUPENABLE, 1372 OMAP2_MCSPI_WAKEUPENABLE_WKEN); 1373 ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN; 1374 1375 omap2_mcspi_set_mode(ctlr); 1376 pm_runtime_mark_last_busy(mcspi->dev); 1377 pm_runtime_put_autosuspend(mcspi->dev); 1378 return 0; 1379 } 1380 1381 static int omap_mcspi_runtime_suspend(struct device *dev) 1382 { 1383 int error; 1384 1385 error = pinctrl_pm_select_idle_state(dev); 1386 if (error) 1387 dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error); 1388 1389 return 0; 1390 } 1391 1392 /* 1393 * When SPI wake up from off-mode, CS is in activate state. If it was in 1394 * inactive state when driver was suspend, then force it to inactive state at 1395 * wake up. 1396 */ 1397 static int omap_mcspi_runtime_resume(struct device *dev) 1398 { 1399 struct spi_controller *ctlr = dev_get_drvdata(dev); 1400 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr); 1401 struct omap2_mcspi_regs *ctx = &mcspi->ctx; 1402 struct omap2_mcspi_cs *cs; 1403 int error; 1404 1405 error = pinctrl_pm_select_default_state(dev); 1406 if (error) 1407 dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error); 1408 1409 /* McSPI: context restore */ 1410 mcspi_write_reg(ctlr, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl); 1411 mcspi_write_reg(ctlr, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable); 1412 1413 list_for_each_entry(cs, &ctx->cs, node) { 1414 /* 1415 * We need to toggle CS state for OMAP take this 1416 * change in account. 1417 */ 1418 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) { 1419 cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE; 1420 writel_relaxed(cs->chconf0, 1421 cs->base + OMAP2_MCSPI_CHCONF0); 1422 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE; 1423 writel_relaxed(cs->chconf0, 1424 cs->base + OMAP2_MCSPI_CHCONF0); 1425 } else { 1426 writel_relaxed(cs->chconf0, 1427 cs->base + OMAP2_MCSPI_CHCONF0); 1428 } 1429 } 1430 1431 return 0; 1432 } 1433 1434 static struct omap2_mcspi_platform_config omap2_pdata = { 1435 .regs_offset = 0, 1436 }; 1437 1438 static struct omap2_mcspi_platform_config omap4_pdata = { 1439 .regs_offset = OMAP4_MCSPI_REG_OFFSET, 1440 }; 1441 1442 static struct omap2_mcspi_platform_config am654_pdata = { 1443 .regs_offset = OMAP4_MCSPI_REG_OFFSET, 1444 .max_xfer_len = SZ_4K - 1, 1445 }; 1446 1447 static const struct of_device_id omap_mcspi_of_match[] = { 1448 { 1449 .compatible = "ti,omap2-mcspi", 1450 .data = &omap2_pdata, 1451 }, 1452 { 1453 .compatible = "ti,omap4-mcspi", 1454 .data = &omap4_pdata, 1455 }, 1456 { 1457 .compatible = "ti,am654-mcspi", 1458 .data = &am654_pdata, 1459 }, 1460 { }, 1461 }; 1462 MODULE_DEVICE_TABLE(of, omap_mcspi_of_match); 1463 1464 static int omap2_mcspi_probe(struct platform_device *pdev) 1465 { 1466 struct spi_controller *ctlr; 1467 const struct omap2_mcspi_platform_config *pdata; 1468 struct omap2_mcspi *mcspi; 1469 struct resource *r; 1470 int status = 0, i; 1471 u32 regs_offset = 0; 1472 struct device_node *node = pdev->dev.of_node; 1473 const struct of_device_id *match; 1474 1475 if (of_property_read_bool(node, "spi-slave")) 1476 ctlr = spi_alloc_target(&pdev->dev, sizeof(*mcspi)); 1477 else 1478 ctlr = spi_alloc_host(&pdev->dev, sizeof(*mcspi)); 1479 if (!ctlr) 1480 return -ENOMEM; 1481 1482 /* the spi->mode bits understood by this driver: */ 1483 ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; 1484 ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); 1485 ctlr->setup = omap2_mcspi_setup; 1486 ctlr->auto_runtime_pm = true; 1487 ctlr->prepare_message = omap2_mcspi_prepare_message; 1488 ctlr->can_dma = omap2_mcspi_can_dma; 1489 ctlr->transfer_one = omap2_mcspi_transfer_one; 1490 ctlr->set_cs = omap2_mcspi_set_cs; 1491 ctlr->cleanup = omap2_mcspi_cleanup; 1492 ctlr->target_abort = omap2_mcspi_target_abort; 1493 ctlr->dev.of_node = node; 1494 ctlr->use_gpio_descriptors = true; 1495 1496 platform_set_drvdata(pdev, ctlr); 1497 1498 mcspi = spi_controller_get_devdata(ctlr); 1499 mcspi->ctlr = ctlr; 1500 1501 match = of_match_device(omap_mcspi_of_match, &pdev->dev); 1502 if (match) { 1503 u32 num_cs = 1; /* default number of chipselect */ 1504 pdata = match->data; 1505 1506 of_property_read_u32(node, "ti,spi-num-cs", &num_cs); 1507 ctlr->num_chipselect = num_cs; 1508 if (of_property_read_bool(node, "ti,pindir-d0-out-d1-in")) 1509 mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN; 1510 } else { 1511 pdata = dev_get_platdata(&pdev->dev); 1512 ctlr->num_chipselect = pdata->num_cs; 1513 mcspi->pin_dir = pdata->pin_dir; 1514 } 1515 regs_offset = pdata->regs_offset; 1516 if (pdata->max_xfer_len) { 1517 mcspi->max_xfer_len = pdata->max_xfer_len; 1518 ctlr->max_transfer_size = omap2_mcspi_max_xfer_size; 1519 } 1520 1521 mcspi->base = devm_platform_get_and_ioremap_resource(pdev, 0, &r); 1522 if (IS_ERR(mcspi->base)) { 1523 status = PTR_ERR(mcspi->base); 1524 goto free_ctlr; 1525 } 1526 mcspi->phys = r->start + regs_offset; 1527 mcspi->base += regs_offset; 1528 1529 mcspi->dev = &pdev->dev; 1530 1531 INIT_LIST_HEAD(&mcspi->ctx.cs); 1532 1533 mcspi->dma_channels = devm_kcalloc(&pdev->dev, ctlr->num_chipselect, 1534 sizeof(struct omap2_mcspi_dma), 1535 GFP_KERNEL); 1536 if (mcspi->dma_channels == NULL) { 1537 status = -ENOMEM; 1538 goto free_ctlr; 1539 } 1540 1541 for (i = 0; i < ctlr->num_chipselect; i++) { 1542 sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i); 1543 sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i); 1544 1545 status = omap2_mcspi_request_dma(mcspi, 1546 &mcspi->dma_channels[i]); 1547 if (status == -EPROBE_DEFER) 1548 goto free_ctlr; 1549 } 1550 1551 status = platform_get_irq(pdev, 0); 1552 if (status < 0) 1553 goto free_ctlr; 1554 init_completion(&mcspi->txdone); 1555 status = devm_request_irq(&pdev->dev, status, 1556 omap2_mcspi_irq_handler, 0, pdev->name, 1557 mcspi); 1558 if (status) { 1559 dev_err(&pdev->dev, "Cannot request IRQ"); 1560 goto free_ctlr; 1561 } 1562 1563 mcspi->ref_clk = devm_clk_get_optional_enabled(&pdev->dev, NULL); 1564 if (mcspi->ref_clk) 1565 mcspi->ref_clk_hz = clk_get_rate(mcspi->ref_clk); 1566 else 1567 mcspi->ref_clk_hz = OMAP2_MCSPI_MAX_FREQ; 1568 ctlr->max_speed_hz = mcspi->ref_clk_hz; 1569 ctlr->min_speed_hz = mcspi->ref_clk_hz >> 15; 1570 1571 pm_runtime_use_autosuspend(&pdev->dev); 1572 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT); 1573 pm_runtime_enable(&pdev->dev); 1574 1575 status = omap2_mcspi_controller_setup(mcspi); 1576 if (status < 0) 1577 goto disable_pm; 1578 1579 status = devm_spi_register_controller(&pdev->dev, ctlr); 1580 if (status < 0) 1581 goto disable_pm; 1582 1583 return status; 1584 1585 disable_pm: 1586 pm_runtime_dont_use_autosuspend(&pdev->dev); 1587 pm_runtime_put_sync(&pdev->dev); 1588 pm_runtime_disable(&pdev->dev); 1589 free_ctlr: 1590 omap2_mcspi_release_dma(ctlr); 1591 spi_controller_put(ctlr); 1592 return status; 1593 } 1594 1595 static void omap2_mcspi_remove(struct platform_device *pdev) 1596 { 1597 struct spi_controller *ctlr = platform_get_drvdata(pdev); 1598 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr); 1599 1600 omap2_mcspi_release_dma(ctlr); 1601 1602 pm_runtime_dont_use_autosuspend(mcspi->dev); 1603 pm_runtime_put_sync(mcspi->dev); 1604 pm_runtime_disable(&pdev->dev); 1605 } 1606 1607 /* work with hotplug and coldplug */ 1608 MODULE_ALIAS("platform:omap2_mcspi"); 1609 1610 static int __maybe_unused omap2_mcspi_suspend(struct device *dev) 1611 { 1612 struct spi_controller *ctlr = dev_get_drvdata(dev); 1613 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr); 1614 int error; 1615 1616 error = pinctrl_pm_select_sleep_state(dev); 1617 if (error) 1618 dev_warn(mcspi->dev, "%s: failed to set pins: %i\n", 1619 __func__, error); 1620 1621 error = spi_controller_suspend(ctlr); 1622 if (error) 1623 dev_warn(mcspi->dev, "%s: controller suspend failed: %i\n", 1624 __func__, error); 1625 1626 return pm_runtime_force_suspend(dev); 1627 } 1628 1629 static int __maybe_unused omap2_mcspi_resume(struct device *dev) 1630 { 1631 struct spi_controller *ctlr = dev_get_drvdata(dev); 1632 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr); 1633 int error; 1634 1635 error = spi_controller_resume(ctlr); 1636 if (error) 1637 dev_warn(mcspi->dev, "%s: controller resume failed: %i\n", 1638 __func__, error); 1639 1640 return pm_runtime_force_resume(dev); 1641 } 1642 1643 static const struct dev_pm_ops omap2_mcspi_pm_ops = { 1644 SET_SYSTEM_SLEEP_PM_OPS(omap2_mcspi_suspend, 1645 omap2_mcspi_resume) 1646 .runtime_suspend = omap_mcspi_runtime_suspend, 1647 .runtime_resume = omap_mcspi_runtime_resume, 1648 }; 1649 1650 static struct platform_driver omap2_mcspi_driver = { 1651 .driver = { 1652 .name = "omap2_mcspi", 1653 .pm = &omap2_mcspi_pm_ops, 1654 .of_match_table = omap_mcspi_of_match, 1655 }, 1656 .probe = omap2_mcspi_probe, 1657 .remove_new = omap2_mcspi_remove, 1658 }; 1659 1660 module_platform_driver(omap2_mcspi_driver); 1661 MODULE_LICENSE("GPL"); 1662