1 /* 2 * SPI driver for NVIDIA's Tegra114 SPI Controller. 3 * 4 * Copyright (c) 2013, NVIDIA CORPORATION. All rights reserved. 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms and conditions of the GNU General Public License, 8 * version 2, as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 13 * more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program. If not, see <http://www.gnu.org/licenses/>. 17 */ 18 19 #include <linux/clk.h> 20 #include <linux/clk/tegra.h> 21 #include <linux/completion.h> 22 #include <linux/delay.h> 23 #include <linux/dmaengine.h> 24 #include <linux/dma-mapping.h> 25 #include <linux/dmapool.h> 26 #include <linux/err.h> 27 #include <linux/init.h> 28 #include <linux/interrupt.h> 29 #include <linux/io.h> 30 #include <linux/kernel.h> 31 #include <linux/kthread.h> 32 #include <linux/module.h> 33 #include <linux/platform_device.h> 34 #include <linux/pm_runtime.h> 35 #include <linux/of.h> 36 #include <linux/of_device.h> 37 #include <linux/spi/spi.h> 38 39 #define SPI_COMMAND1 0x000 40 #define SPI_BIT_LENGTH(x) (((x) & 0x1f) << 0) 41 #define SPI_PACKED (1 << 5) 42 #define SPI_TX_EN (1 << 11) 43 #define SPI_RX_EN (1 << 12) 44 #define SPI_BOTH_EN_BYTE (1 << 13) 45 #define SPI_BOTH_EN_BIT (1 << 14) 46 #define SPI_LSBYTE_FE (1 << 15) 47 #define SPI_LSBIT_FE (1 << 16) 48 #define SPI_BIDIROE (1 << 17) 49 #define SPI_IDLE_SDA_DRIVE_LOW (0 << 18) 50 #define SPI_IDLE_SDA_DRIVE_HIGH (1 << 18) 51 #define SPI_IDLE_SDA_PULL_LOW (2 << 18) 52 #define SPI_IDLE_SDA_PULL_HIGH (3 << 18) 53 #define SPI_IDLE_SDA_MASK (3 << 18) 54 #define SPI_CS_SS_VAL (1 << 20) 55 #define SPI_CS_SW_HW (1 << 21) 56 /* SPI_CS_POL_INACTIVE bits are default high */ 57 #define SPI_CS_POL_INACTIVE 22 58 #define SPI_CS_POL_INACTIVE_0 (1 << 22) 59 #define SPI_CS_POL_INACTIVE_1 (1 << 23) 60 #define SPI_CS_POL_INACTIVE_2 (1 << 24) 61 #define SPI_CS_POL_INACTIVE_3 (1 << 25) 62 #define SPI_CS_POL_INACTIVE_MASK (0xF << 22) 63 64 #define SPI_CS_SEL_0 (0 << 26) 65 #define SPI_CS_SEL_1 (1 << 26) 66 #define SPI_CS_SEL_2 (2 << 26) 67 #define SPI_CS_SEL_3 (3 << 26) 68 #define SPI_CS_SEL_MASK (3 << 26) 69 #define SPI_CS_SEL(x) (((x) & 0x3) << 26) 70 #define SPI_CONTROL_MODE_0 (0 << 28) 71 #define SPI_CONTROL_MODE_1 (1 << 28) 72 #define SPI_CONTROL_MODE_2 (2 << 28) 73 #define SPI_CONTROL_MODE_3 (3 << 28) 74 #define SPI_CONTROL_MODE_MASK (3 << 28) 75 #define SPI_MODE_SEL(x) (((x) & 0x3) << 28) 76 #define SPI_M_S (1 << 30) 77 #define SPI_PIO (1 << 31) 78 79 #define SPI_COMMAND2 0x004 80 #define SPI_TX_TAP_DELAY(x) (((x) & 0x3F) << 6) 81 #define SPI_RX_TAP_DELAY(x) (((x) & 0x3F) << 0) 82 83 #define SPI_CS_TIMING1 0x008 84 #define SPI_SETUP_HOLD(setup, hold) (((setup) << 4) | (hold)) 85 #define SPI_CS_SETUP_HOLD(reg, cs, val) \ 86 ((((val) & 0xFFu) << ((cs) * 8)) | \ 87 ((reg) & ~(0xFFu << ((cs) * 8)))) 88 89 #define SPI_CS_TIMING2 0x00C 90 #define CYCLES_BETWEEN_PACKETS_0(x) (((x) & 0x1F) << 0) 91 #define CS_ACTIVE_BETWEEN_PACKETS_0 (1 << 5) 92 #define CYCLES_BETWEEN_PACKETS_1(x) (((x) & 0x1F) << 8) 93 #define CS_ACTIVE_BETWEEN_PACKETS_1 (1 << 13) 94 #define CYCLES_BETWEEN_PACKETS_2(x) (((x) & 0x1F) << 16) 95 #define CS_ACTIVE_BETWEEN_PACKETS_2 (1 << 21) 96 #define CYCLES_BETWEEN_PACKETS_3(x) (((x) & 0x1F) << 24) 97 #define CS_ACTIVE_BETWEEN_PACKETS_3 (1 << 29) 98 #define SPI_SET_CS_ACTIVE_BETWEEN_PACKETS(reg, cs, val) \ 99 (reg = (((val) & 0x1) << ((cs) * 8 + 5)) | \ 100 ((reg) & ~(1 << ((cs) * 8 + 5)))) 101 #define SPI_SET_CYCLES_BETWEEN_PACKETS(reg, cs, val) \ 102 (reg = (((val) & 0xF) << ((cs) * 8)) | \ 103 ((reg) & ~(0xF << ((cs) * 8)))) 104 105 #define SPI_TRANS_STATUS 0x010 106 #define SPI_BLK_CNT(val) (((val) >> 0) & 0xFFFF) 107 #define SPI_SLV_IDLE_COUNT(val) (((val) >> 16) & 0xFF) 108 #define SPI_RDY (1 << 30) 109 110 #define SPI_FIFO_STATUS 0x014 111 #define SPI_RX_FIFO_EMPTY (1 << 0) 112 #define SPI_RX_FIFO_FULL (1 << 1) 113 #define SPI_TX_FIFO_EMPTY (1 << 2) 114 #define SPI_TX_FIFO_FULL (1 << 3) 115 #define SPI_RX_FIFO_UNF (1 << 4) 116 #define SPI_RX_FIFO_OVF (1 << 5) 117 #define SPI_TX_FIFO_UNF (1 << 6) 118 #define SPI_TX_FIFO_OVF (1 << 7) 119 #define SPI_ERR (1 << 8) 120 #define SPI_TX_FIFO_FLUSH (1 << 14) 121 #define SPI_RX_FIFO_FLUSH (1 << 15) 122 #define SPI_TX_FIFO_EMPTY_COUNT(val) (((val) >> 16) & 0x7F) 123 #define SPI_RX_FIFO_FULL_COUNT(val) (((val) >> 23) & 0x7F) 124 #define SPI_FRAME_END (1 << 30) 125 #define SPI_CS_INACTIVE (1 << 31) 126 127 #define SPI_FIFO_ERROR (SPI_RX_FIFO_UNF | \ 128 SPI_RX_FIFO_OVF | SPI_TX_FIFO_UNF | SPI_TX_FIFO_OVF) 129 #define SPI_FIFO_EMPTY (SPI_RX_FIFO_EMPTY | SPI_TX_FIFO_EMPTY) 130 131 #define SPI_TX_DATA 0x018 132 #define SPI_RX_DATA 0x01C 133 134 #define SPI_DMA_CTL 0x020 135 #define SPI_TX_TRIG_1 (0 << 15) 136 #define SPI_TX_TRIG_4 (1 << 15) 137 #define SPI_TX_TRIG_8 (2 << 15) 138 #define SPI_TX_TRIG_16 (3 << 15) 139 #define SPI_TX_TRIG_MASK (3 << 15) 140 #define SPI_RX_TRIG_1 (0 << 19) 141 #define SPI_RX_TRIG_4 (1 << 19) 142 #define SPI_RX_TRIG_8 (2 << 19) 143 #define SPI_RX_TRIG_16 (3 << 19) 144 #define SPI_RX_TRIG_MASK (3 << 19) 145 #define SPI_IE_TX (1 << 28) 146 #define SPI_IE_RX (1 << 29) 147 #define SPI_CONT (1 << 30) 148 #define SPI_DMA (1 << 31) 149 #define SPI_DMA_EN SPI_DMA 150 151 #define SPI_DMA_BLK 0x024 152 #define SPI_DMA_BLK_SET(x) (((x) & 0xFFFF) << 0) 153 154 #define SPI_TX_FIFO 0x108 155 #define SPI_RX_FIFO 0x188 156 #define MAX_CHIP_SELECT 4 157 #define SPI_FIFO_DEPTH 64 158 #define DATA_DIR_TX (1 << 0) 159 #define DATA_DIR_RX (1 << 1) 160 161 #define SPI_DMA_TIMEOUT (msecs_to_jiffies(1000)) 162 #define DEFAULT_SPI_DMA_BUF_LEN (16*1024) 163 #define TX_FIFO_EMPTY_COUNT_MAX SPI_TX_FIFO_EMPTY_COUNT(0x40) 164 #define RX_FIFO_FULL_COUNT_ZERO SPI_RX_FIFO_FULL_COUNT(0) 165 #define MAX_HOLD_CYCLES 16 166 #define SPI_DEFAULT_SPEED 25000000 167 168 #define MAX_CHIP_SELECT 4 169 #define SPI_FIFO_DEPTH 64 170 171 struct tegra_spi_data { 172 struct device *dev; 173 struct spi_master *master; 174 spinlock_t lock; 175 176 struct clk *clk; 177 void __iomem *base; 178 phys_addr_t phys; 179 unsigned irq; 180 int dma_req_sel; 181 u32 spi_max_frequency; 182 u32 cur_speed; 183 184 struct spi_device *cur_spi; 185 unsigned cur_pos; 186 unsigned cur_len; 187 unsigned words_per_32bit; 188 unsigned bytes_per_word; 189 unsigned curr_dma_words; 190 unsigned cur_direction; 191 192 unsigned cur_rx_pos; 193 unsigned cur_tx_pos; 194 195 unsigned dma_buf_size; 196 unsigned max_buf_size; 197 bool is_curr_dma_xfer; 198 199 struct completion rx_dma_complete; 200 struct completion tx_dma_complete; 201 202 u32 tx_status; 203 u32 rx_status; 204 u32 status_reg; 205 bool is_packed; 206 unsigned long packed_size; 207 208 u32 command1_reg; 209 u32 dma_control_reg; 210 u32 def_command1_reg; 211 u32 spi_cs_timing; 212 213 struct completion xfer_completion; 214 struct spi_transfer *curr_xfer; 215 struct dma_chan *rx_dma_chan; 216 u32 *rx_dma_buf; 217 dma_addr_t rx_dma_phys; 218 struct dma_async_tx_descriptor *rx_dma_desc; 219 220 struct dma_chan *tx_dma_chan; 221 u32 *tx_dma_buf; 222 dma_addr_t tx_dma_phys; 223 struct dma_async_tx_descriptor *tx_dma_desc; 224 }; 225 226 static int tegra_spi_runtime_suspend(struct device *dev); 227 static int tegra_spi_runtime_resume(struct device *dev); 228 229 static inline unsigned long tegra_spi_readl(struct tegra_spi_data *tspi, 230 unsigned long reg) 231 { 232 return readl(tspi->base + reg); 233 } 234 235 static inline void tegra_spi_writel(struct tegra_spi_data *tspi, 236 unsigned long val, unsigned long reg) 237 { 238 writel(val, tspi->base + reg); 239 240 /* Read back register to make sure that register writes completed */ 241 if (reg != SPI_TX_FIFO) 242 readl(tspi->base + SPI_COMMAND1); 243 } 244 245 static void tegra_spi_clear_status(struct tegra_spi_data *tspi) 246 { 247 unsigned long val; 248 249 /* Write 1 to clear status register */ 250 val = tegra_spi_readl(tspi, SPI_TRANS_STATUS); 251 tegra_spi_writel(tspi, val, SPI_TRANS_STATUS); 252 253 /* Clear fifo status error if any */ 254 val = tegra_spi_readl(tspi, SPI_FIFO_STATUS); 255 if (val & SPI_ERR) 256 tegra_spi_writel(tspi, SPI_ERR | SPI_FIFO_ERROR, 257 SPI_FIFO_STATUS); 258 } 259 260 static unsigned tegra_spi_calculate_curr_xfer_param( 261 struct spi_device *spi, struct tegra_spi_data *tspi, 262 struct spi_transfer *t) 263 { 264 unsigned remain_len = t->len - tspi->cur_pos; 265 unsigned max_word; 266 unsigned bits_per_word = t->bits_per_word; 267 unsigned max_len; 268 unsigned total_fifo_words; 269 270 tspi->bytes_per_word = (bits_per_word - 1) / 8 + 1; 271 272 if (bits_per_word == 8 || bits_per_word == 16) { 273 tspi->is_packed = 1; 274 tspi->words_per_32bit = 32/bits_per_word; 275 } else { 276 tspi->is_packed = 0; 277 tspi->words_per_32bit = 1; 278 } 279 280 if (tspi->is_packed) { 281 max_len = min(remain_len, tspi->max_buf_size); 282 tspi->curr_dma_words = max_len/tspi->bytes_per_word; 283 total_fifo_words = (max_len + 3) / 4; 284 } else { 285 max_word = (remain_len - 1) / tspi->bytes_per_word + 1; 286 max_word = min(max_word, tspi->max_buf_size/4); 287 tspi->curr_dma_words = max_word; 288 total_fifo_words = max_word; 289 } 290 return total_fifo_words; 291 } 292 293 static unsigned tegra_spi_fill_tx_fifo_from_client_txbuf( 294 struct tegra_spi_data *tspi, struct spi_transfer *t) 295 { 296 unsigned nbytes; 297 unsigned tx_empty_count; 298 unsigned long fifo_status; 299 unsigned max_n_32bit; 300 unsigned i, count; 301 unsigned long x; 302 unsigned int written_words; 303 unsigned fifo_words_left; 304 u8 *tx_buf = (u8 *)t->tx_buf + tspi->cur_tx_pos; 305 306 fifo_status = tegra_spi_readl(tspi, SPI_FIFO_STATUS); 307 tx_empty_count = SPI_TX_FIFO_EMPTY_COUNT(fifo_status); 308 309 if (tspi->is_packed) { 310 fifo_words_left = tx_empty_count * tspi->words_per_32bit; 311 written_words = min(fifo_words_left, tspi->curr_dma_words); 312 nbytes = written_words * tspi->bytes_per_word; 313 max_n_32bit = DIV_ROUND_UP(nbytes, 4); 314 for (count = 0; count < max_n_32bit; count++) { 315 x = 0; 316 for (i = 0; (i < 4) && nbytes; i++, nbytes--) 317 x |= (*tx_buf++) << (i*8); 318 tegra_spi_writel(tspi, x, SPI_TX_FIFO); 319 } 320 } else { 321 max_n_32bit = min(tspi->curr_dma_words, tx_empty_count); 322 written_words = max_n_32bit; 323 nbytes = written_words * tspi->bytes_per_word; 324 for (count = 0; count < max_n_32bit; count++) { 325 x = 0; 326 for (i = 0; nbytes && (i < tspi->bytes_per_word); 327 i++, nbytes--) 328 x |= ((*tx_buf++) << i*8); 329 tegra_spi_writel(tspi, x, SPI_TX_FIFO); 330 } 331 } 332 tspi->cur_tx_pos += written_words * tspi->bytes_per_word; 333 return written_words; 334 } 335 336 static unsigned int tegra_spi_read_rx_fifo_to_client_rxbuf( 337 struct tegra_spi_data *tspi, struct spi_transfer *t) 338 { 339 unsigned rx_full_count; 340 unsigned long fifo_status; 341 unsigned i, count; 342 unsigned long x; 343 unsigned int read_words = 0; 344 unsigned len; 345 u8 *rx_buf = (u8 *)t->rx_buf + tspi->cur_rx_pos; 346 347 fifo_status = tegra_spi_readl(tspi, SPI_FIFO_STATUS); 348 rx_full_count = SPI_RX_FIFO_FULL_COUNT(fifo_status); 349 if (tspi->is_packed) { 350 len = tspi->curr_dma_words * tspi->bytes_per_word; 351 for (count = 0; count < rx_full_count; count++) { 352 x = tegra_spi_readl(tspi, SPI_RX_FIFO); 353 for (i = 0; len && (i < 4); i++, len--) 354 *rx_buf++ = (x >> i*8) & 0xFF; 355 } 356 tspi->cur_rx_pos += tspi->curr_dma_words * tspi->bytes_per_word; 357 read_words += tspi->curr_dma_words; 358 } else { 359 unsigned int rx_mask; 360 unsigned int bits_per_word = t->bits_per_word; 361 362 rx_mask = (1 << bits_per_word) - 1; 363 for (count = 0; count < rx_full_count; count++) { 364 x = tegra_spi_readl(tspi, SPI_RX_FIFO); 365 x &= rx_mask; 366 for (i = 0; (i < tspi->bytes_per_word); i++) 367 *rx_buf++ = (x >> (i*8)) & 0xFF; 368 } 369 tspi->cur_rx_pos += rx_full_count * tspi->bytes_per_word; 370 read_words += rx_full_count; 371 } 372 return read_words; 373 } 374 375 static void tegra_spi_copy_client_txbuf_to_spi_txbuf( 376 struct tegra_spi_data *tspi, struct spi_transfer *t) 377 { 378 unsigned len; 379 380 /* Make the dma buffer to read by cpu */ 381 dma_sync_single_for_cpu(tspi->dev, tspi->tx_dma_phys, 382 tspi->dma_buf_size, DMA_TO_DEVICE); 383 384 if (tspi->is_packed) { 385 len = tspi->curr_dma_words * tspi->bytes_per_word; 386 memcpy(tspi->tx_dma_buf, t->tx_buf + tspi->cur_pos, len); 387 } else { 388 unsigned int i; 389 unsigned int count; 390 u8 *tx_buf = (u8 *)t->tx_buf + tspi->cur_tx_pos; 391 unsigned consume = tspi->curr_dma_words * tspi->bytes_per_word; 392 unsigned int x; 393 394 for (count = 0; count < tspi->curr_dma_words; count++) { 395 x = 0; 396 for (i = 0; consume && (i < tspi->bytes_per_word); 397 i++, consume--) 398 x |= ((*tx_buf++) << i * 8); 399 tspi->tx_dma_buf[count] = x; 400 } 401 } 402 tspi->cur_tx_pos += tspi->curr_dma_words * tspi->bytes_per_word; 403 404 /* Make the dma buffer to read by dma */ 405 dma_sync_single_for_device(tspi->dev, tspi->tx_dma_phys, 406 tspi->dma_buf_size, DMA_TO_DEVICE); 407 } 408 409 static void tegra_spi_copy_spi_rxbuf_to_client_rxbuf( 410 struct tegra_spi_data *tspi, struct spi_transfer *t) 411 { 412 unsigned len; 413 414 /* Make the dma buffer to read by cpu */ 415 dma_sync_single_for_cpu(tspi->dev, tspi->rx_dma_phys, 416 tspi->dma_buf_size, DMA_FROM_DEVICE); 417 418 if (tspi->is_packed) { 419 len = tspi->curr_dma_words * tspi->bytes_per_word; 420 memcpy(t->rx_buf + tspi->cur_rx_pos, tspi->rx_dma_buf, len); 421 } else { 422 unsigned int i; 423 unsigned int count; 424 unsigned char *rx_buf = t->rx_buf + tspi->cur_rx_pos; 425 unsigned int x; 426 unsigned int rx_mask; 427 unsigned int bits_per_word = t->bits_per_word; 428 429 rx_mask = (1 << bits_per_word) - 1; 430 for (count = 0; count < tspi->curr_dma_words; count++) { 431 x = tspi->rx_dma_buf[count]; 432 x &= rx_mask; 433 for (i = 0; (i < tspi->bytes_per_word); i++) 434 *rx_buf++ = (x >> (i*8)) & 0xFF; 435 } 436 } 437 tspi->cur_rx_pos += tspi->curr_dma_words * tspi->bytes_per_word; 438 439 /* Make the dma buffer to read by dma */ 440 dma_sync_single_for_device(tspi->dev, tspi->rx_dma_phys, 441 tspi->dma_buf_size, DMA_FROM_DEVICE); 442 } 443 444 static void tegra_spi_dma_complete(void *args) 445 { 446 struct completion *dma_complete = args; 447 448 complete(dma_complete); 449 } 450 451 static int tegra_spi_start_tx_dma(struct tegra_spi_data *tspi, int len) 452 { 453 INIT_COMPLETION(tspi->tx_dma_complete); 454 tspi->tx_dma_desc = dmaengine_prep_slave_single(tspi->tx_dma_chan, 455 tspi->tx_dma_phys, len, DMA_MEM_TO_DEV, 456 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 457 if (!tspi->tx_dma_desc) { 458 dev_err(tspi->dev, "Not able to get desc for Tx\n"); 459 return -EIO; 460 } 461 462 tspi->tx_dma_desc->callback = tegra_spi_dma_complete; 463 tspi->tx_dma_desc->callback_param = &tspi->tx_dma_complete; 464 465 dmaengine_submit(tspi->tx_dma_desc); 466 dma_async_issue_pending(tspi->tx_dma_chan); 467 return 0; 468 } 469 470 static int tegra_spi_start_rx_dma(struct tegra_spi_data *tspi, int len) 471 { 472 INIT_COMPLETION(tspi->rx_dma_complete); 473 tspi->rx_dma_desc = dmaengine_prep_slave_single(tspi->rx_dma_chan, 474 tspi->rx_dma_phys, len, DMA_DEV_TO_MEM, 475 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 476 if (!tspi->rx_dma_desc) { 477 dev_err(tspi->dev, "Not able to get desc for Rx\n"); 478 return -EIO; 479 } 480 481 tspi->rx_dma_desc->callback = tegra_spi_dma_complete; 482 tspi->rx_dma_desc->callback_param = &tspi->rx_dma_complete; 483 484 dmaengine_submit(tspi->rx_dma_desc); 485 dma_async_issue_pending(tspi->rx_dma_chan); 486 return 0; 487 } 488 489 static int tegra_spi_start_dma_based_transfer( 490 struct tegra_spi_data *tspi, struct spi_transfer *t) 491 { 492 unsigned long val; 493 unsigned int len; 494 int ret = 0; 495 unsigned long status; 496 497 /* Make sure that Rx and Tx fifo are empty */ 498 status = tegra_spi_readl(tspi, SPI_FIFO_STATUS); 499 if ((status & SPI_FIFO_EMPTY) != SPI_FIFO_EMPTY) { 500 dev_err(tspi->dev, 501 "Rx/Tx fifo are not empty status 0x%08lx\n", status); 502 return -EIO; 503 } 504 505 val = SPI_DMA_BLK_SET(tspi->curr_dma_words - 1); 506 tegra_spi_writel(tspi, val, SPI_DMA_BLK); 507 508 if (tspi->is_packed) 509 len = DIV_ROUND_UP(tspi->curr_dma_words * tspi->bytes_per_word, 510 4) * 4; 511 else 512 len = tspi->curr_dma_words * 4; 513 514 /* Set attention level based on length of transfer */ 515 if (len & 0xF) 516 val |= SPI_TX_TRIG_1 | SPI_RX_TRIG_1; 517 else if (((len) >> 4) & 0x1) 518 val |= SPI_TX_TRIG_4 | SPI_RX_TRIG_4; 519 else 520 val |= SPI_TX_TRIG_8 | SPI_RX_TRIG_8; 521 522 if (tspi->cur_direction & DATA_DIR_TX) 523 val |= SPI_IE_TX; 524 525 if (tspi->cur_direction & DATA_DIR_RX) 526 val |= SPI_IE_RX; 527 528 tegra_spi_writel(tspi, val, SPI_DMA_CTL); 529 tspi->dma_control_reg = val; 530 531 if (tspi->cur_direction & DATA_DIR_TX) { 532 tegra_spi_copy_client_txbuf_to_spi_txbuf(tspi, t); 533 ret = tegra_spi_start_tx_dma(tspi, len); 534 if (ret < 0) { 535 dev_err(tspi->dev, 536 "Starting tx dma failed, err %d\n", ret); 537 return ret; 538 } 539 } 540 541 if (tspi->cur_direction & DATA_DIR_RX) { 542 /* Make the dma buffer to read by dma */ 543 dma_sync_single_for_device(tspi->dev, tspi->rx_dma_phys, 544 tspi->dma_buf_size, DMA_FROM_DEVICE); 545 546 ret = tegra_spi_start_rx_dma(tspi, len); 547 if (ret < 0) { 548 dev_err(tspi->dev, 549 "Starting rx dma failed, err %d\n", ret); 550 if (tspi->cur_direction & DATA_DIR_TX) 551 dmaengine_terminate_all(tspi->tx_dma_chan); 552 return ret; 553 } 554 } 555 tspi->is_curr_dma_xfer = true; 556 tspi->dma_control_reg = val; 557 558 val |= SPI_DMA_EN; 559 tegra_spi_writel(tspi, val, SPI_DMA_CTL); 560 return ret; 561 } 562 563 static int tegra_spi_start_cpu_based_transfer( 564 struct tegra_spi_data *tspi, struct spi_transfer *t) 565 { 566 unsigned long val; 567 unsigned cur_words; 568 569 if (tspi->cur_direction & DATA_DIR_TX) 570 cur_words = tegra_spi_fill_tx_fifo_from_client_txbuf(tspi, t); 571 else 572 cur_words = tspi->curr_dma_words; 573 574 val = SPI_DMA_BLK_SET(cur_words - 1); 575 tegra_spi_writel(tspi, val, SPI_DMA_BLK); 576 577 val = 0; 578 if (tspi->cur_direction & DATA_DIR_TX) 579 val |= SPI_IE_TX; 580 581 if (tspi->cur_direction & DATA_DIR_RX) 582 val |= SPI_IE_RX; 583 584 tegra_spi_writel(tspi, val, SPI_DMA_CTL); 585 tspi->dma_control_reg = val; 586 587 tspi->is_curr_dma_xfer = false; 588 589 val |= SPI_DMA_EN; 590 tegra_spi_writel(tspi, val, SPI_DMA_CTL); 591 return 0; 592 } 593 594 static int tegra_spi_init_dma_param(struct tegra_spi_data *tspi, 595 bool dma_to_memory) 596 { 597 struct dma_chan *dma_chan; 598 u32 *dma_buf; 599 dma_addr_t dma_phys; 600 int ret; 601 struct dma_slave_config dma_sconfig; 602 dma_cap_mask_t mask; 603 604 dma_cap_zero(mask); 605 dma_cap_set(DMA_SLAVE, mask); 606 dma_chan = dma_request_channel(mask, NULL, NULL); 607 if (!dma_chan) { 608 dev_err(tspi->dev, 609 "Dma channel is not available, will try later\n"); 610 return -EPROBE_DEFER; 611 } 612 613 dma_buf = dma_alloc_coherent(tspi->dev, tspi->dma_buf_size, 614 &dma_phys, GFP_KERNEL); 615 if (!dma_buf) { 616 dev_err(tspi->dev, " Not able to allocate the dma buffer\n"); 617 dma_release_channel(dma_chan); 618 return -ENOMEM; 619 } 620 621 dma_sconfig.slave_id = tspi->dma_req_sel; 622 if (dma_to_memory) { 623 dma_sconfig.src_addr = tspi->phys + SPI_RX_FIFO; 624 dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; 625 dma_sconfig.src_maxburst = 0; 626 } else { 627 dma_sconfig.dst_addr = tspi->phys + SPI_TX_FIFO; 628 dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; 629 dma_sconfig.dst_maxburst = 0; 630 } 631 632 ret = dmaengine_slave_config(dma_chan, &dma_sconfig); 633 if (ret) 634 goto scrub; 635 if (dma_to_memory) { 636 tspi->rx_dma_chan = dma_chan; 637 tspi->rx_dma_buf = dma_buf; 638 tspi->rx_dma_phys = dma_phys; 639 } else { 640 tspi->tx_dma_chan = dma_chan; 641 tspi->tx_dma_buf = dma_buf; 642 tspi->tx_dma_phys = dma_phys; 643 } 644 return 0; 645 646 scrub: 647 dma_free_coherent(tspi->dev, tspi->dma_buf_size, dma_buf, dma_phys); 648 dma_release_channel(dma_chan); 649 return ret; 650 } 651 652 static void tegra_spi_deinit_dma_param(struct tegra_spi_data *tspi, 653 bool dma_to_memory) 654 { 655 u32 *dma_buf; 656 dma_addr_t dma_phys; 657 struct dma_chan *dma_chan; 658 659 if (dma_to_memory) { 660 dma_buf = tspi->rx_dma_buf; 661 dma_chan = tspi->rx_dma_chan; 662 dma_phys = tspi->rx_dma_phys; 663 tspi->rx_dma_chan = NULL; 664 tspi->rx_dma_buf = NULL; 665 } else { 666 dma_buf = tspi->tx_dma_buf; 667 dma_chan = tspi->tx_dma_chan; 668 dma_phys = tspi->tx_dma_phys; 669 tspi->tx_dma_buf = NULL; 670 tspi->tx_dma_chan = NULL; 671 } 672 if (!dma_chan) 673 return; 674 675 dma_free_coherent(tspi->dev, tspi->dma_buf_size, dma_buf, dma_phys); 676 dma_release_channel(dma_chan); 677 } 678 679 static int tegra_spi_start_transfer_one(struct spi_device *spi, 680 struct spi_transfer *t, bool is_first_of_msg, 681 bool is_single_xfer) 682 { 683 struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); 684 u32 speed = t->speed_hz; 685 u8 bits_per_word = t->bits_per_word; 686 unsigned total_fifo_words; 687 int ret; 688 unsigned long command1; 689 int req_mode; 690 691 if (speed != tspi->cur_speed) { 692 clk_set_rate(tspi->clk, speed); 693 tspi->cur_speed = speed; 694 } 695 696 tspi->cur_spi = spi; 697 tspi->cur_pos = 0; 698 tspi->cur_rx_pos = 0; 699 tspi->cur_tx_pos = 0; 700 tspi->curr_xfer = t; 701 total_fifo_words = tegra_spi_calculate_curr_xfer_param(spi, tspi, t); 702 703 if (is_first_of_msg) { 704 tegra_spi_clear_status(tspi); 705 706 command1 = tspi->def_command1_reg; 707 command1 |= SPI_BIT_LENGTH(bits_per_word - 1); 708 709 command1 &= ~SPI_CONTROL_MODE_MASK; 710 req_mode = spi->mode & 0x3; 711 if (req_mode == SPI_MODE_0) 712 command1 |= SPI_CONTROL_MODE_0; 713 else if (req_mode == SPI_MODE_1) 714 command1 |= SPI_CONTROL_MODE_1; 715 else if (req_mode == SPI_MODE_2) 716 command1 |= SPI_CONTROL_MODE_2; 717 else if (req_mode == SPI_MODE_3) 718 command1 |= SPI_CONTROL_MODE_3; 719 720 tegra_spi_writel(tspi, command1, SPI_COMMAND1); 721 722 command1 |= SPI_CS_SW_HW; 723 if (spi->mode & SPI_CS_HIGH) 724 command1 |= SPI_CS_SS_VAL; 725 else 726 command1 &= ~SPI_CS_SS_VAL; 727 728 tegra_spi_writel(tspi, 0, SPI_COMMAND2); 729 } else { 730 command1 = tspi->command1_reg; 731 command1 &= ~SPI_BIT_LENGTH(~0); 732 command1 |= SPI_BIT_LENGTH(bits_per_word - 1); 733 } 734 735 if (tspi->is_packed) 736 command1 |= SPI_PACKED; 737 738 command1 &= ~(SPI_CS_SEL_MASK | SPI_TX_EN | SPI_RX_EN); 739 tspi->cur_direction = 0; 740 if (t->rx_buf) { 741 command1 |= SPI_RX_EN; 742 tspi->cur_direction |= DATA_DIR_RX; 743 } 744 if (t->tx_buf) { 745 command1 |= SPI_TX_EN; 746 tspi->cur_direction |= DATA_DIR_TX; 747 } 748 command1 |= SPI_CS_SEL(spi->chip_select); 749 tegra_spi_writel(tspi, command1, SPI_COMMAND1); 750 tspi->command1_reg = command1; 751 752 dev_dbg(tspi->dev, "The def 0x%x and written 0x%lx\n", 753 tspi->def_command1_reg, command1); 754 755 if (total_fifo_words > SPI_FIFO_DEPTH) 756 ret = tegra_spi_start_dma_based_transfer(tspi, t); 757 else 758 ret = tegra_spi_start_cpu_based_transfer(tspi, t); 759 return ret; 760 } 761 762 static int tegra_spi_setup(struct spi_device *spi) 763 { 764 struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); 765 unsigned long val; 766 unsigned long flags; 767 int ret; 768 unsigned int cs_pol_bit[MAX_CHIP_SELECT] = { 769 SPI_CS_POL_INACTIVE_0, 770 SPI_CS_POL_INACTIVE_1, 771 SPI_CS_POL_INACTIVE_2, 772 SPI_CS_POL_INACTIVE_3, 773 }; 774 775 dev_dbg(&spi->dev, "setup %d bpw, %scpol, %scpha, %dHz\n", 776 spi->bits_per_word, 777 spi->mode & SPI_CPOL ? "" : "~", 778 spi->mode & SPI_CPHA ? "" : "~", 779 spi->max_speed_hz); 780 781 BUG_ON(spi->chip_select >= MAX_CHIP_SELECT); 782 783 /* Set speed to the spi max fequency if spi device has not set */ 784 spi->max_speed_hz = spi->max_speed_hz ? : tspi->spi_max_frequency; 785 786 ret = pm_runtime_get_sync(tspi->dev); 787 if (ret < 0) { 788 dev_err(tspi->dev, "pm runtime failed, e = %d\n", ret); 789 return ret; 790 } 791 792 spin_lock_irqsave(&tspi->lock, flags); 793 val = tspi->def_command1_reg; 794 if (spi->mode & SPI_CS_HIGH) 795 val &= ~cs_pol_bit[spi->chip_select]; 796 else 797 val |= cs_pol_bit[spi->chip_select]; 798 tspi->def_command1_reg = val; 799 tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1); 800 spin_unlock_irqrestore(&tspi->lock, flags); 801 802 pm_runtime_put(tspi->dev); 803 return 0; 804 } 805 806 static int tegra_spi_transfer_one_message(struct spi_master *master, 807 struct spi_message *msg) 808 { 809 bool is_first_msg = true; 810 int single_xfer; 811 struct tegra_spi_data *tspi = spi_master_get_devdata(master); 812 struct spi_transfer *xfer; 813 struct spi_device *spi = msg->spi; 814 int ret; 815 816 msg->status = 0; 817 msg->actual_length = 0; 818 819 single_xfer = list_is_singular(&msg->transfers); 820 list_for_each_entry(xfer, &msg->transfers, transfer_list) { 821 INIT_COMPLETION(tspi->xfer_completion); 822 ret = tegra_spi_start_transfer_one(spi, xfer, 823 is_first_msg, single_xfer); 824 if (ret < 0) { 825 dev_err(tspi->dev, 826 "spi can not start transfer, err %d\n", ret); 827 goto exit; 828 } 829 is_first_msg = false; 830 ret = wait_for_completion_timeout(&tspi->xfer_completion, 831 SPI_DMA_TIMEOUT); 832 if (WARN_ON(ret == 0)) { 833 dev_err(tspi->dev, 834 "spi trasfer timeout, err %d\n", ret); 835 ret = -EIO; 836 goto exit; 837 } 838 839 if (tspi->tx_status || tspi->rx_status) { 840 dev_err(tspi->dev, "Error in Transfer\n"); 841 ret = -EIO; 842 goto exit; 843 } 844 msg->actual_length += xfer->len; 845 if (xfer->cs_change && xfer->delay_usecs) { 846 tegra_spi_writel(tspi, tspi->def_command1_reg, 847 SPI_COMMAND1); 848 udelay(xfer->delay_usecs); 849 } 850 } 851 ret = 0; 852 exit: 853 tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1); 854 msg->status = ret; 855 spi_finalize_current_message(master); 856 return ret; 857 } 858 859 static irqreturn_t handle_cpu_based_xfer(struct tegra_spi_data *tspi) 860 { 861 struct spi_transfer *t = tspi->curr_xfer; 862 unsigned long flags; 863 864 spin_lock_irqsave(&tspi->lock, flags); 865 if (tspi->tx_status || tspi->rx_status) { 866 dev_err(tspi->dev, "CpuXfer ERROR bit set 0x%x\n", 867 tspi->status_reg); 868 dev_err(tspi->dev, "CpuXfer 0x%08x:0x%08x\n", 869 tspi->command1_reg, tspi->dma_control_reg); 870 tegra_periph_reset_assert(tspi->clk); 871 udelay(2); 872 tegra_periph_reset_deassert(tspi->clk); 873 complete(&tspi->xfer_completion); 874 goto exit; 875 } 876 877 if (tspi->cur_direction & DATA_DIR_RX) 878 tegra_spi_read_rx_fifo_to_client_rxbuf(tspi, t); 879 880 if (tspi->cur_direction & DATA_DIR_TX) 881 tspi->cur_pos = tspi->cur_tx_pos; 882 else 883 tspi->cur_pos = tspi->cur_rx_pos; 884 885 if (tspi->cur_pos == t->len) { 886 complete(&tspi->xfer_completion); 887 goto exit; 888 } 889 890 tegra_spi_calculate_curr_xfer_param(tspi->cur_spi, tspi, t); 891 tegra_spi_start_cpu_based_transfer(tspi, t); 892 exit: 893 spin_unlock_irqrestore(&tspi->lock, flags); 894 return IRQ_HANDLED; 895 } 896 897 static irqreturn_t handle_dma_based_xfer(struct tegra_spi_data *tspi) 898 { 899 struct spi_transfer *t = tspi->curr_xfer; 900 long wait_status; 901 int err = 0; 902 unsigned total_fifo_words; 903 unsigned long flags; 904 905 /* Abort dmas if any error */ 906 if (tspi->cur_direction & DATA_DIR_TX) { 907 if (tspi->tx_status) { 908 dmaengine_terminate_all(tspi->tx_dma_chan); 909 err += 1; 910 } else { 911 wait_status = wait_for_completion_interruptible_timeout( 912 &tspi->tx_dma_complete, SPI_DMA_TIMEOUT); 913 if (wait_status <= 0) { 914 dmaengine_terminate_all(tspi->tx_dma_chan); 915 dev_err(tspi->dev, "TxDma Xfer failed\n"); 916 err += 1; 917 } 918 } 919 } 920 921 if (tspi->cur_direction & DATA_DIR_RX) { 922 if (tspi->rx_status) { 923 dmaengine_terminate_all(tspi->rx_dma_chan); 924 err += 2; 925 } else { 926 wait_status = wait_for_completion_interruptible_timeout( 927 &tspi->rx_dma_complete, SPI_DMA_TIMEOUT); 928 if (wait_status <= 0) { 929 dmaengine_terminate_all(tspi->rx_dma_chan); 930 dev_err(tspi->dev, "RxDma Xfer failed\n"); 931 err += 2; 932 } 933 } 934 } 935 936 spin_lock_irqsave(&tspi->lock, flags); 937 if (err) { 938 dev_err(tspi->dev, "DmaXfer: ERROR bit set 0x%x\n", 939 tspi->status_reg); 940 dev_err(tspi->dev, "DmaXfer 0x%08x:0x%08x\n", 941 tspi->command1_reg, tspi->dma_control_reg); 942 tegra_periph_reset_assert(tspi->clk); 943 udelay(2); 944 tegra_periph_reset_deassert(tspi->clk); 945 complete(&tspi->xfer_completion); 946 spin_unlock_irqrestore(&tspi->lock, flags); 947 return IRQ_HANDLED; 948 } 949 950 if (tspi->cur_direction & DATA_DIR_RX) 951 tegra_spi_copy_spi_rxbuf_to_client_rxbuf(tspi, t); 952 953 if (tspi->cur_direction & DATA_DIR_TX) 954 tspi->cur_pos = tspi->cur_tx_pos; 955 else 956 tspi->cur_pos = tspi->cur_rx_pos; 957 958 if (tspi->cur_pos == t->len) { 959 complete(&tspi->xfer_completion); 960 goto exit; 961 } 962 963 /* Continue transfer in current message */ 964 total_fifo_words = tegra_spi_calculate_curr_xfer_param(tspi->cur_spi, 965 tspi, t); 966 if (total_fifo_words > SPI_FIFO_DEPTH) 967 err = tegra_spi_start_dma_based_transfer(tspi, t); 968 else 969 err = tegra_spi_start_cpu_based_transfer(tspi, t); 970 971 exit: 972 spin_unlock_irqrestore(&tspi->lock, flags); 973 return IRQ_HANDLED; 974 } 975 976 static irqreturn_t tegra_spi_isr_thread(int irq, void *context_data) 977 { 978 struct tegra_spi_data *tspi = context_data; 979 980 if (!tspi->is_curr_dma_xfer) 981 return handle_cpu_based_xfer(tspi); 982 return handle_dma_based_xfer(tspi); 983 } 984 985 static irqreturn_t tegra_spi_isr(int irq, void *context_data) 986 { 987 struct tegra_spi_data *tspi = context_data; 988 989 tspi->status_reg = tegra_spi_readl(tspi, SPI_FIFO_STATUS); 990 if (tspi->cur_direction & DATA_DIR_TX) 991 tspi->tx_status = tspi->status_reg & 992 (SPI_TX_FIFO_UNF | SPI_TX_FIFO_OVF); 993 994 if (tspi->cur_direction & DATA_DIR_RX) 995 tspi->rx_status = tspi->status_reg & 996 (SPI_RX_FIFO_OVF | SPI_RX_FIFO_UNF); 997 tegra_spi_clear_status(tspi); 998 999 return IRQ_WAKE_THREAD; 1000 } 1001 1002 static void tegra_spi_parse_dt(struct platform_device *pdev, 1003 struct tegra_spi_data *tspi) 1004 { 1005 struct device_node *np = pdev->dev.of_node; 1006 u32 of_dma[2]; 1007 1008 if (of_property_read_u32_array(np, "nvidia,dma-request-selector", 1009 of_dma, 2) >= 0) 1010 tspi->dma_req_sel = of_dma[1]; 1011 1012 if (of_property_read_u32(np, "spi-max-frequency", 1013 &tspi->spi_max_frequency)) 1014 tspi->spi_max_frequency = 25000000; /* 25MHz */ 1015 } 1016 1017 static struct of_device_id tegra_spi_of_match[] = { 1018 { .compatible = "nvidia,tegra114-spi", }, 1019 {} 1020 }; 1021 MODULE_DEVICE_TABLE(of, tegra_spi_of_match); 1022 1023 static int tegra_spi_probe(struct platform_device *pdev) 1024 { 1025 struct spi_master *master; 1026 struct tegra_spi_data *tspi; 1027 struct resource *r; 1028 int ret, spi_irq; 1029 1030 master = spi_alloc_master(&pdev->dev, sizeof(*tspi)); 1031 if (!master) { 1032 dev_err(&pdev->dev, "master allocation failed\n"); 1033 return -ENOMEM; 1034 } 1035 platform_set_drvdata(pdev, master); 1036 tspi = spi_master_get_devdata(master); 1037 1038 /* Parse DT */ 1039 tegra_spi_parse_dt(pdev, tspi); 1040 1041 /* the spi->mode bits understood by this driver: */ 1042 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; 1043 master->setup = tegra_spi_setup; 1044 master->transfer_one_message = tegra_spi_transfer_one_message; 1045 master->num_chipselect = MAX_CHIP_SELECT; 1046 master->bus_num = -1; 1047 master->auto_runtime_pm = true; 1048 1049 tspi->master = master; 1050 tspi->dev = &pdev->dev; 1051 spin_lock_init(&tspi->lock); 1052 1053 r = platform_get_resource(pdev, IORESOURCE_MEM, 0); 1054 tspi->base = devm_ioremap_resource(&pdev->dev, r); 1055 if (IS_ERR(tspi->base)) { 1056 ret = PTR_ERR(tspi->base); 1057 goto exit_free_master; 1058 } 1059 tspi->phys = r->start; 1060 1061 spi_irq = platform_get_irq(pdev, 0); 1062 tspi->irq = spi_irq; 1063 ret = request_threaded_irq(tspi->irq, tegra_spi_isr, 1064 tegra_spi_isr_thread, IRQF_ONESHOT, 1065 dev_name(&pdev->dev), tspi); 1066 if (ret < 0) { 1067 dev_err(&pdev->dev, "Failed to register ISR for IRQ %d\n", 1068 tspi->irq); 1069 goto exit_free_master; 1070 } 1071 1072 tspi->clk = devm_clk_get(&pdev->dev, "spi"); 1073 if (IS_ERR(tspi->clk)) { 1074 dev_err(&pdev->dev, "can not get clock\n"); 1075 ret = PTR_ERR(tspi->clk); 1076 goto exit_free_irq; 1077 } 1078 1079 tspi->max_buf_size = SPI_FIFO_DEPTH << 2; 1080 tspi->dma_buf_size = DEFAULT_SPI_DMA_BUF_LEN; 1081 1082 if (tspi->dma_req_sel) { 1083 ret = tegra_spi_init_dma_param(tspi, true); 1084 if (ret < 0) { 1085 dev_err(&pdev->dev, "RxDma Init failed, err %d\n", ret); 1086 goto exit_free_irq; 1087 } 1088 1089 ret = tegra_spi_init_dma_param(tspi, false); 1090 if (ret < 0) { 1091 dev_err(&pdev->dev, "TxDma Init failed, err %d\n", ret); 1092 goto exit_rx_dma_free; 1093 } 1094 tspi->max_buf_size = tspi->dma_buf_size; 1095 init_completion(&tspi->tx_dma_complete); 1096 init_completion(&tspi->rx_dma_complete); 1097 } 1098 1099 init_completion(&tspi->xfer_completion); 1100 1101 pm_runtime_enable(&pdev->dev); 1102 if (!pm_runtime_enabled(&pdev->dev)) { 1103 ret = tegra_spi_runtime_resume(&pdev->dev); 1104 if (ret) 1105 goto exit_pm_disable; 1106 } 1107 1108 ret = pm_runtime_get_sync(&pdev->dev); 1109 if (ret < 0) { 1110 dev_err(&pdev->dev, "pm runtime get failed, e = %d\n", ret); 1111 goto exit_pm_disable; 1112 } 1113 tspi->def_command1_reg = SPI_M_S; 1114 tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1); 1115 pm_runtime_put(&pdev->dev); 1116 1117 master->dev.of_node = pdev->dev.of_node; 1118 ret = spi_register_master(master); 1119 if (ret < 0) { 1120 dev_err(&pdev->dev, "can not register to master err %d\n", ret); 1121 goto exit_pm_disable; 1122 } 1123 return ret; 1124 1125 exit_pm_disable: 1126 pm_runtime_disable(&pdev->dev); 1127 if (!pm_runtime_status_suspended(&pdev->dev)) 1128 tegra_spi_runtime_suspend(&pdev->dev); 1129 tegra_spi_deinit_dma_param(tspi, false); 1130 exit_rx_dma_free: 1131 tegra_spi_deinit_dma_param(tspi, true); 1132 exit_free_irq: 1133 free_irq(spi_irq, tspi); 1134 exit_free_master: 1135 spi_master_put(master); 1136 return ret; 1137 } 1138 1139 static int tegra_spi_remove(struct platform_device *pdev) 1140 { 1141 struct spi_master *master = platform_get_drvdata(pdev); 1142 struct tegra_spi_data *tspi = spi_master_get_devdata(master); 1143 1144 free_irq(tspi->irq, tspi); 1145 spi_unregister_master(master); 1146 1147 if (tspi->tx_dma_chan) 1148 tegra_spi_deinit_dma_param(tspi, false); 1149 1150 if (tspi->rx_dma_chan) 1151 tegra_spi_deinit_dma_param(tspi, true); 1152 1153 pm_runtime_disable(&pdev->dev); 1154 if (!pm_runtime_status_suspended(&pdev->dev)) 1155 tegra_spi_runtime_suspend(&pdev->dev); 1156 1157 return 0; 1158 } 1159 1160 #ifdef CONFIG_PM_SLEEP 1161 static int tegra_spi_suspend(struct device *dev) 1162 { 1163 struct spi_master *master = dev_get_drvdata(dev); 1164 1165 return spi_master_suspend(master); 1166 } 1167 1168 static int tegra_spi_resume(struct device *dev) 1169 { 1170 struct spi_master *master = dev_get_drvdata(dev); 1171 struct tegra_spi_data *tspi = spi_master_get_devdata(master); 1172 int ret; 1173 1174 ret = pm_runtime_get_sync(dev); 1175 if (ret < 0) { 1176 dev_err(dev, "pm runtime failed, e = %d\n", ret); 1177 return ret; 1178 } 1179 tegra_spi_writel(tspi, tspi->command1_reg, SPI_COMMAND1); 1180 pm_runtime_put(dev); 1181 1182 return spi_master_resume(master); 1183 } 1184 #endif 1185 1186 static int tegra_spi_runtime_suspend(struct device *dev) 1187 { 1188 struct spi_master *master = dev_get_drvdata(dev); 1189 struct tegra_spi_data *tspi = spi_master_get_devdata(master); 1190 1191 /* Flush all write which are in PPSB queue by reading back */ 1192 tegra_spi_readl(tspi, SPI_COMMAND1); 1193 1194 clk_disable_unprepare(tspi->clk); 1195 return 0; 1196 } 1197 1198 static int tegra_spi_runtime_resume(struct device *dev) 1199 { 1200 struct spi_master *master = dev_get_drvdata(dev); 1201 struct tegra_spi_data *tspi = spi_master_get_devdata(master); 1202 int ret; 1203 1204 ret = clk_prepare_enable(tspi->clk); 1205 if (ret < 0) { 1206 dev_err(tspi->dev, "clk_prepare failed: %d\n", ret); 1207 return ret; 1208 } 1209 return 0; 1210 } 1211 1212 static const struct dev_pm_ops tegra_spi_pm_ops = { 1213 SET_RUNTIME_PM_OPS(tegra_spi_runtime_suspend, 1214 tegra_spi_runtime_resume, NULL) 1215 SET_SYSTEM_SLEEP_PM_OPS(tegra_spi_suspend, tegra_spi_resume) 1216 }; 1217 static struct platform_driver tegra_spi_driver = { 1218 .driver = { 1219 .name = "spi-tegra114", 1220 .owner = THIS_MODULE, 1221 .pm = &tegra_spi_pm_ops, 1222 .of_match_table = tegra_spi_of_match, 1223 }, 1224 .probe = tegra_spi_probe, 1225 .remove = tegra_spi_remove, 1226 }; 1227 module_platform_driver(tegra_spi_driver); 1228 1229 MODULE_ALIAS("platform:spi-tegra114"); 1230 MODULE_DESCRIPTION("NVIDIA Tegra114 SPI Controller Driver"); 1231 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); 1232 MODULE_LICENSE("GPL v2"); 1233