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