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