1 /* 2 * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved. 3 * Copyright (C) 2008 Juergen Beisert 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU General Public License 7 * as published by the Free Software Foundation; either version 2 8 * of the License, or (at your option) any later version. 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the 16 * Free Software Foundation 17 * 51 Franklin Street, Fifth Floor 18 * Boston, MA 02110-1301, USA. 19 */ 20 21 #include <linux/clk.h> 22 #include <linux/completion.h> 23 #include <linux/delay.h> 24 #include <linux/err.h> 25 #include <linux/gpio.h> 26 #include <linux/init.h> 27 #include <linux/interrupt.h> 28 #include <linux/io.h> 29 #include <linux/irq.h> 30 #include <linux/kernel.h> 31 #include <linux/module.h> 32 #include <linux/platform_device.h> 33 #include <linux/slab.h> 34 #include <linux/spi/spi.h> 35 #include <linux/spi/spi_bitbang.h> 36 #include <linux/types.h> 37 #include <linux/of.h> 38 #include <linux/of_device.h> 39 #include <linux/of_gpio.h> 40 41 #include <mach/spi.h> 42 43 #define DRIVER_NAME "spi_imx" 44 45 #define MXC_CSPIRXDATA 0x00 46 #define MXC_CSPITXDATA 0x04 47 #define MXC_CSPICTRL 0x08 48 #define MXC_CSPIINT 0x0c 49 #define MXC_RESET 0x1c 50 51 /* generic defines to abstract from the different register layouts */ 52 #define MXC_INT_RR (1 << 0) /* Receive data ready interrupt */ 53 #define MXC_INT_TE (1 << 1) /* Transmit FIFO empty interrupt */ 54 55 struct spi_imx_config { 56 unsigned int speed_hz; 57 unsigned int bpw; 58 unsigned int mode; 59 u8 cs; 60 }; 61 62 enum spi_imx_devtype { 63 IMX1_CSPI, 64 IMX21_CSPI, 65 IMX27_CSPI, 66 IMX31_CSPI, 67 IMX35_CSPI, /* CSPI on all i.mx except above */ 68 IMX51_ECSPI, /* ECSPI on i.mx51 and later */ 69 }; 70 71 struct spi_imx_data; 72 73 struct spi_imx_devtype_data { 74 void (*intctrl)(struct spi_imx_data *, int); 75 int (*config)(struct spi_imx_data *, struct spi_imx_config *); 76 void (*trigger)(struct spi_imx_data *); 77 int (*rx_available)(struct spi_imx_data *); 78 void (*reset)(struct spi_imx_data *); 79 enum spi_imx_devtype devtype; 80 }; 81 82 struct spi_imx_data { 83 struct spi_bitbang bitbang; 84 85 struct completion xfer_done; 86 void __iomem *base; 87 int irq; 88 struct clk *clk; 89 unsigned long spi_clk; 90 91 unsigned int count; 92 void (*tx)(struct spi_imx_data *); 93 void (*rx)(struct spi_imx_data *); 94 void *rx_buf; 95 const void *tx_buf; 96 unsigned int txfifo; /* number of words pushed in tx FIFO */ 97 98 struct spi_imx_devtype_data *devtype_data; 99 int chipselect[0]; 100 }; 101 102 static inline int is_imx27_cspi(struct spi_imx_data *d) 103 { 104 return d->devtype_data->devtype == IMX27_CSPI; 105 } 106 107 static inline int is_imx35_cspi(struct spi_imx_data *d) 108 { 109 return d->devtype_data->devtype == IMX35_CSPI; 110 } 111 112 static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d) 113 { 114 return (d->devtype_data->devtype == IMX51_ECSPI) ? 64 : 8; 115 } 116 117 #define MXC_SPI_BUF_RX(type) \ 118 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx) \ 119 { \ 120 unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA); \ 121 \ 122 if (spi_imx->rx_buf) { \ 123 *(type *)spi_imx->rx_buf = val; \ 124 spi_imx->rx_buf += sizeof(type); \ 125 } \ 126 } 127 128 #define MXC_SPI_BUF_TX(type) \ 129 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx) \ 130 { \ 131 type val = 0; \ 132 \ 133 if (spi_imx->tx_buf) { \ 134 val = *(type *)spi_imx->tx_buf; \ 135 spi_imx->tx_buf += sizeof(type); \ 136 } \ 137 \ 138 spi_imx->count -= sizeof(type); \ 139 \ 140 writel(val, spi_imx->base + MXC_CSPITXDATA); \ 141 } 142 143 MXC_SPI_BUF_RX(u8) 144 MXC_SPI_BUF_TX(u8) 145 MXC_SPI_BUF_RX(u16) 146 MXC_SPI_BUF_TX(u16) 147 MXC_SPI_BUF_RX(u32) 148 MXC_SPI_BUF_TX(u32) 149 150 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set 151 * (which is currently not the case in this driver) 152 */ 153 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192, 154 256, 384, 512, 768, 1024}; 155 156 /* MX21, MX27 */ 157 static unsigned int spi_imx_clkdiv_1(unsigned int fin, 158 unsigned int fspi, unsigned int max) 159 { 160 int i; 161 162 for (i = 2; i < max; i++) 163 if (fspi * mxc_clkdivs[i] >= fin) 164 return i; 165 166 return max; 167 } 168 169 /* MX1, MX31, MX35, MX51 CSPI */ 170 static unsigned int spi_imx_clkdiv_2(unsigned int fin, 171 unsigned int fspi) 172 { 173 int i, div = 4; 174 175 for (i = 0; i < 7; i++) { 176 if (fspi * div >= fin) 177 return i; 178 div <<= 1; 179 } 180 181 return 7; 182 } 183 184 #define MX51_ECSPI_CTRL 0x08 185 #define MX51_ECSPI_CTRL_ENABLE (1 << 0) 186 #define MX51_ECSPI_CTRL_XCH (1 << 2) 187 #define MX51_ECSPI_CTRL_MODE_MASK (0xf << 4) 188 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET 8 189 #define MX51_ECSPI_CTRL_PREDIV_OFFSET 12 190 #define MX51_ECSPI_CTRL_CS(cs) ((cs) << 18) 191 #define MX51_ECSPI_CTRL_BL_OFFSET 20 192 193 #define MX51_ECSPI_CONFIG 0x0c 194 #define MX51_ECSPI_CONFIG_SCLKPHA(cs) (1 << ((cs) + 0)) 195 #define MX51_ECSPI_CONFIG_SCLKPOL(cs) (1 << ((cs) + 4)) 196 #define MX51_ECSPI_CONFIG_SBBCTRL(cs) (1 << ((cs) + 8)) 197 #define MX51_ECSPI_CONFIG_SSBPOL(cs) (1 << ((cs) + 12)) 198 199 #define MX51_ECSPI_INT 0x10 200 #define MX51_ECSPI_INT_TEEN (1 << 0) 201 #define MX51_ECSPI_INT_RREN (1 << 3) 202 203 #define MX51_ECSPI_STAT 0x18 204 #define MX51_ECSPI_STAT_RR (1 << 3) 205 206 /* MX51 eCSPI */ 207 static unsigned int mx51_ecspi_clkdiv(unsigned int fin, unsigned int fspi) 208 { 209 /* 210 * there are two 4-bit dividers, the pre-divider divides by 211 * $pre, the post-divider by 2^$post 212 */ 213 unsigned int pre, post; 214 215 if (unlikely(fspi > fin)) 216 return 0; 217 218 post = fls(fin) - fls(fspi); 219 if (fin > fspi << post) 220 post++; 221 222 /* now we have: (fin <= fspi << post) with post being minimal */ 223 224 post = max(4U, post) - 4; 225 if (unlikely(post > 0xf)) { 226 pr_err("%s: cannot set clock freq: %u (base freq: %u)\n", 227 __func__, fspi, fin); 228 return 0xff; 229 } 230 231 pre = DIV_ROUND_UP(fin, fspi << post) - 1; 232 233 pr_debug("%s: fin: %u, fspi: %u, post: %u, pre: %u\n", 234 __func__, fin, fspi, post, pre); 235 return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) | 236 (post << MX51_ECSPI_CTRL_POSTDIV_OFFSET); 237 } 238 239 static void __maybe_unused mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable) 240 { 241 unsigned val = 0; 242 243 if (enable & MXC_INT_TE) 244 val |= MX51_ECSPI_INT_TEEN; 245 246 if (enable & MXC_INT_RR) 247 val |= MX51_ECSPI_INT_RREN; 248 249 writel(val, spi_imx->base + MX51_ECSPI_INT); 250 } 251 252 static void __maybe_unused mx51_ecspi_trigger(struct spi_imx_data *spi_imx) 253 { 254 u32 reg; 255 256 reg = readl(spi_imx->base + MX51_ECSPI_CTRL); 257 reg |= MX51_ECSPI_CTRL_XCH; 258 writel(reg, spi_imx->base + MX51_ECSPI_CTRL); 259 } 260 261 static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx, 262 struct spi_imx_config *config) 263 { 264 u32 ctrl = MX51_ECSPI_CTRL_ENABLE, cfg = 0; 265 266 /* 267 * The hardware seems to have a race condition when changing modes. The 268 * current assumption is that the selection of the channel arrives 269 * earlier in the hardware than the mode bits when they are written at 270 * the same time. 271 * So set master mode for all channels as we do not support slave mode. 272 */ 273 ctrl |= MX51_ECSPI_CTRL_MODE_MASK; 274 275 /* set clock speed */ 276 ctrl |= mx51_ecspi_clkdiv(spi_imx->spi_clk, config->speed_hz); 277 278 /* set chip select to use */ 279 ctrl |= MX51_ECSPI_CTRL_CS(config->cs); 280 281 ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET; 282 283 cfg |= MX51_ECSPI_CONFIG_SBBCTRL(config->cs); 284 285 if (config->mode & SPI_CPHA) 286 cfg |= MX51_ECSPI_CONFIG_SCLKPHA(config->cs); 287 288 if (config->mode & SPI_CPOL) 289 cfg |= MX51_ECSPI_CONFIG_SCLKPOL(config->cs); 290 291 if (config->mode & SPI_CS_HIGH) 292 cfg |= MX51_ECSPI_CONFIG_SSBPOL(config->cs); 293 294 writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL); 295 writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG); 296 297 return 0; 298 } 299 300 static int __maybe_unused mx51_ecspi_rx_available(struct spi_imx_data *spi_imx) 301 { 302 return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR; 303 } 304 305 static void __maybe_unused mx51_ecspi_reset(struct spi_imx_data *spi_imx) 306 { 307 /* drain receive buffer */ 308 while (mx51_ecspi_rx_available(spi_imx)) 309 readl(spi_imx->base + MXC_CSPIRXDATA); 310 } 311 312 #define MX31_INTREG_TEEN (1 << 0) 313 #define MX31_INTREG_RREN (1 << 3) 314 315 #define MX31_CSPICTRL_ENABLE (1 << 0) 316 #define MX31_CSPICTRL_MASTER (1 << 1) 317 #define MX31_CSPICTRL_XCH (1 << 2) 318 #define MX31_CSPICTRL_POL (1 << 4) 319 #define MX31_CSPICTRL_PHA (1 << 5) 320 #define MX31_CSPICTRL_SSCTL (1 << 6) 321 #define MX31_CSPICTRL_SSPOL (1 << 7) 322 #define MX31_CSPICTRL_BC_SHIFT 8 323 #define MX35_CSPICTRL_BL_SHIFT 20 324 #define MX31_CSPICTRL_CS_SHIFT 24 325 #define MX35_CSPICTRL_CS_SHIFT 12 326 #define MX31_CSPICTRL_DR_SHIFT 16 327 328 #define MX31_CSPISTATUS 0x14 329 #define MX31_STATUS_RR (1 << 3) 330 331 /* These functions also work for the i.MX35, but be aware that 332 * the i.MX35 has a slightly different register layout for bits 333 * we do not use here. 334 */ 335 static void __maybe_unused mx31_intctrl(struct spi_imx_data *spi_imx, int enable) 336 { 337 unsigned int val = 0; 338 339 if (enable & MXC_INT_TE) 340 val |= MX31_INTREG_TEEN; 341 if (enable & MXC_INT_RR) 342 val |= MX31_INTREG_RREN; 343 344 writel(val, spi_imx->base + MXC_CSPIINT); 345 } 346 347 static void __maybe_unused mx31_trigger(struct spi_imx_data *spi_imx) 348 { 349 unsigned int reg; 350 351 reg = readl(spi_imx->base + MXC_CSPICTRL); 352 reg |= MX31_CSPICTRL_XCH; 353 writel(reg, spi_imx->base + MXC_CSPICTRL); 354 } 355 356 static int __maybe_unused mx31_config(struct spi_imx_data *spi_imx, 357 struct spi_imx_config *config) 358 { 359 unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER; 360 int cs = spi_imx->chipselect[config->cs]; 361 362 reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) << 363 MX31_CSPICTRL_DR_SHIFT; 364 365 if (is_imx35_cspi(spi_imx)) { 366 reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT; 367 reg |= MX31_CSPICTRL_SSCTL; 368 } else { 369 reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT; 370 } 371 372 if (config->mode & SPI_CPHA) 373 reg |= MX31_CSPICTRL_PHA; 374 if (config->mode & SPI_CPOL) 375 reg |= MX31_CSPICTRL_POL; 376 if (config->mode & SPI_CS_HIGH) 377 reg |= MX31_CSPICTRL_SSPOL; 378 if (cs < 0) 379 reg |= (cs + 32) << 380 (is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT : 381 MX31_CSPICTRL_CS_SHIFT); 382 383 writel(reg, spi_imx->base + MXC_CSPICTRL); 384 385 return 0; 386 } 387 388 static int __maybe_unused mx31_rx_available(struct spi_imx_data *spi_imx) 389 { 390 return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR; 391 } 392 393 static void __maybe_unused mx31_reset(struct spi_imx_data *spi_imx) 394 { 395 /* drain receive buffer */ 396 while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR) 397 readl(spi_imx->base + MXC_CSPIRXDATA); 398 } 399 400 #define MX21_INTREG_RR (1 << 4) 401 #define MX21_INTREG_TEEN (1 << 9) 402 #define MX21_INTREG_RREN (1 << 13) 403 404 #define MX21_CSPICTRL_POL (1 << 5) 405 #define MX21_CSPICTRL_PHA (1 << 6) 406 #define MX21_CSPICTRL_SSPOL (1 << 8) 407 #define MX21_CSPICTRL_XCH (1 << 9) 408 #define MX21_CSPICTRL_ENABLE (1 << 10) 409 #define MX21_CSPICTRL_MASTER (1 << 11) 410 #define MX21_CSPICTRL_DR_SHIFT 14 411 #define MX21_CSPICTRL_CS_SHIFT 19 412 413 static void __maybe_unused mx21_intctrl(struct spi_imx_data *spi_imx, int enable) 414 { 415 unsigned int val = 0; 416 417 if (enable & MXC_INT_TE) 418 val |= MX21_INTREG_TEEN; 419 if (enable & MXC_INT_RR) 420 val |= MX21_INTREG_RREN; 421 422 writel(val, spi_imx->base + MXC_CSPIINT); 423 } 424 425 static void __maybe_unused mx21_trigger(struct spi_imx_data *spi_imx) 426 { 427 unsigned int reg; 428 429 reg = readl(spi_imx->base + MXC_CSPICTRL); 430 reg |= MX21_CSPICTRL_XCH; 431 writel(reg, spi_imx->base + MXC_CSPICTRL); 432 } 433 434 static int __maybe_unused mx21_config(struct spi_imx_data *spi_imx, 435 struct spi_imx_config *config) 436 { 437 unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER; 438 int cs = spi_imx->chipselect[config->cs]; 439 unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18; 440 441 reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max) << 442 MX21_CSPICTRL_DR_SHIFT; 443 reg |= config->bpw - 1; 444 445 if (config->mode & SPI_CPHA) 446 reg |= MX21_CSPICTRL_PHA; 447 if (config->mode & SPI_CPOL) 448 reg |= MX21_CSPICTRL_POL; 449 if (config->mode & SPI_CS_HIGH) 450 reg |= MX21_CSPICTRL_SSPOL; 451 if (cs < 0) 452 reg |= (cs + 32) << MX21_CSPICTRL_CS_SHIFT; 453 454 writel(reg, spi_imx->base + MXC_CSPICTRL); 455 456 return 0; 457 } 458 459 static int __maybe_unused mx21_rx_available(struct spi_imx_data *spi_imx) 460 { 461 return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR; 462 } 463 464 static void __maybe_unused mx21_reset(struct spi_imx_data *spi_imx) 465 { 466 writel(1, spi_imx->base + MXC_RESET); 467 } 468 469 #define MX1_INTREG_RR (1 << 3) 470 #define MX1_INTREG_TEEN (1 << 8) 471 #define MX1_INTREG_RREN (1 << 11) 472 473 #define MX1_CSPICTRL_POL (1 << 4) 474 #define MX1_CSPICTRL_PHA (1 << 5) 475 #define MX1_CSPICTRL_XCH (1 << 8) 476 #define MX1_CSPICTRL_ENABLE (1 << 9) 477 #define MX1_CSPICTRL_MASTER (1 << 10) 478 #define MX1_CSPICTRL_DR_SHIFT 13 479 480 static void __maybe_unused mx1_intctrl(struct spi_imx_data *spi_imx, int enable) 481 { 482 unsigned int val = 0; 483 484 if (enable & MXC_INT_TE) 485 val |= MX1_INTREG_TEEN; 486 if (enable & MXC_INT_RR) 487 val |= MX1_INTREG_RREN; 488 489 writel(val, spi_imx->base + MXC_CSPIINT); 490 } 491 492 static void __maybe_unused mx1_trigger(struct spi_imx_data *spi_imx) 493 { 494 unsigned int reg; 495 496 reg = readl(spi_imx->base + MXC_CSPICTRL); 497 reg |= MX1_CSPICTRL_XCH; 498 writel(reg, spi_imx->base + MXC_CSPICTRL); 499 } 500 501 static int __maybe_unused mx1_config(struct spi_imx_data *spi_imx, 502 struct spi_imx_config *config) 503 { 504 unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER; 505 506 reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) << 507 MX1_CSPICTRL_DR_SHIFT; 508 reg |= config->bpw - 1; 509 510 if (config->mode & SPI_CPHA) 511 reg |= MX1_CSPICTRL_PHA; 512 if (config->mode & SPI_CPOL) 513 reg |= MX1_CSPICTRL_POL; 514 515 writel(reg, spi_imx->base + MXC_CSPICTRL); 516 517 return 0; 518 } 519 520 static int __maybe_unused mx1_rx_available(struct spi_imx_data *spi_imx) 521 { 522 return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR; 523 } 524 525 static void __maybe_unused mx1_reset(struct spi_imx_data *spi_imx) 526 { 527 writel(1, spi_imx->base + MXC_RESET); 528 } 529 530 static struct spi_imx_devtype_data imx1_cspi_devtype_data = { 531 .intctrl = mx1_intctrl, 532 .config = mx1_config, 533 .trigger = mx1_trigger, 534 .rx_available = mx1_rx_available, 535 .reset = mx1_reset, 536 .devtype = IMX1_CSPI, 537 }; 538 539 static struct spi_imx_devtype_data imx21_cspi_devtype_data = { 540 .intctrl = mx21_intctrl, 541 .config = mx21_config, 542 .trigger = mx21_trigger, 543 .rx_available = mx21_rx_available, 544 .reset = mx21_reset, 545 .devtype = IMX21_CSPI, 546 }; 547 548 static struct spi_imx_devtype_data imx27_cspi_devtype_data = { 549 /* i.mx27 cspi shares the functions with i.mx21 one */ 550 .intctrl = mx21_intctrl, 551 .config = mx21_config, 552 .trigger = mx21_trigger, 553 .rx_available = mx21_rx_available, 554 .reset = mx21_reset, 555 .devtype = IMX27_CSPI, 556 }; 557 558 static struct spi_imx_devtype_data imx31_cspi_devtype_data = { 559 .intctrl = mx31_intctrl, 560 .config = mx31_config, 561 .trigger = mx31_trigger, 562 .rx_available = mx31_rx_available, 563 .reset = mx31_reset, 564 .devtype = IMX31_CSPI, 565 }; 566 567 static struct spi_imx_devtype_data imx35_cspi_devtype_data = { 568 /* i.mx35 and later cspi shares the functions with i.mx31 one */ 569 .intctrl = mx31_intctrl, 570 .config = mx31_config, 571 .trigger = mx31_trigger, 572 .rx_available = mx31_rx_available, 573 .reset = mx31_reset, 574 .devtype = IMX35_CSPI, 575 }; 576 577 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = { 578 .intctrl = mx51_ecspi_intctrl, 579 .config = mx51_ecspi_config, 580 .trigger = mx51_ecspi_trigger, 581 .rx_available = mx51_ecspi_rx_available, 582 .reset = mx51_ecspi_reset, 583 .devtype = IMX51_ECSPI, 584 }; 585 586 static struct platform_device_id spi_imx_devtype[] = { 587 { 588 .name = "imx1-cspi", 589 .driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data, 590 }, { 591 .name = "imx21-cspi", 592 .driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data, 593 }, { 594 .name = "imx27-cspi", 595 .driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data, 596 }, { 597 .name = "imx31-cspi", 598 .driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data, 599 }, { 600 .name = "imx35-cspi", 601 .driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data, 602 }, { 603 .name = "imx51-ecspi", 604 .driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data, 605 }, { 606 /* sentinel */ 607 } 608 }; 609 610 static const struct of_device_id spi_imx_dt_ids[] = { 611 { .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, }, 612 { .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, }, 613 { .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, }, 614 { .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, }, 615 { .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, }, 616 { .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, }, 617 { /* sentinel */ } 618 }; 619 620 static void spi_imx_chipselect(struct spi_device *spi, int is_active) 621 { 622 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); 623 int gpio = spi_imx->chipselect[spi->chip_select]; 624 int active = is_active != BITBANG_CS_INACTIVE; 625 int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH); 626 627 if (gpio < 0) 628 return; 629 630 gpio_set_value(gpio, dev_is_lowactive ^ active); 631 } 632 633 static void spi_imx_push(struct spi_imx_data *spi_imx) 634 { 635 while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) { 636 if (!spi_imx->count) 637 break; 638 spi_imx->tx(spi_imx); 639 spi_imx->txfifo++; 640 } 641 642 spi_imx->devtype_data->trigger(spi_imx); 643 } 644 645 static irqreturn_t spi_imx_isr(int irq, void *dev_id) 646 { 647 struct spi_imx_data *spi_imx = dev_id; 648 649 while (spi_imx->devtype_data->rx_available(spi_imx)) { 650 spi_imx->rx(spi_imx); 651 spi_imx->txfifo--; 652 } 653 654 if (spi_imx->count) { 655 spi_imx_push(spi_imx); 656 return IRQ_HANDLED; 657 } 658 659 if (spi_imx->txfifo) { 660 /* No data left to push, but still waiting for rx data, 661 * enable receive data available interrupt. 662 */ 663 spi_imx->devtype_data->intctrl( 664 spi_imx, MXC_INT_RR); 665 return IRQ_HANDLED; 666 } 667 668 spi_imx->devtype_data->intctrl(spi_imx, 0); 669 complete(&spi_imx->xfer_done); 670 671 return IRQ_HANDLED; 672 } 673 674 static int spi_imx_setupxfer(struct spi_device *spi, 675 struct spi_transfer *t) 676 { 677 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); 678 struct spi_imx_config config; 679 680 config.bpw = t ? t->bits_per_word : spi->bits_per_word; 681 config.speed_hz = t ? t->speed_hz : spi->max_speed_hz; 682 config.mode = spi->mode; 683 config.cs = spi->chip_select; 684 685 if (!config.speed_hz) 686 config.speed_hz = spi->max_speed_hz; 687 if (!config.bpw) 688 config.bpw = spi->bits_per_word; 689 if (!config.speed_hz) 690 config.speed_hz = spi->max_speed_hz; 691 692 /* Initialize the functions for transfer */ 693 if (config.bpw <= 8) { 694 spi_imx->rx = spi_imx_buf_rx_u8; 695 spi_imx->tx = spi_imx_buf_tx_u8; 696 } else if (config.bpw <= 16) { 697 spi_imx->rx = spi_imx_buf_rx_u16; 698 spi_imx->tx = spi_imx_buf_tx_u16; 699 } else if (config.bpw <= 32) { 700 spi_imx->rx = spi_imx_buf_rx_u32; 701 spi_imx->tx = spi_imx_buf_tx_u32; 702 } else 703 BUG(); 704 705 spi_imx->devtype_data->config(spi_imx, &config); 706 707 return 0; 708 } 709 710 static int spi_imx_transfer(struct spi_device *spi, 711 struct spi_transfer *transfer) 712 { 713 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); 714 715 spi_imx->tx_buf = transfer->tx_buf; 716 spi_imx->rx_buf = transfer->rx_buf; 717 spi_imx->count = transfer->len; 718 spi_imx->txfifo = 0; 719 720 init_completion(&spi_imx->xfer_done); 721 722 spi_imx_push(spi_imx); 723 724 spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE); 725 726 wait_for_completion(&spi_imx->xfer_done); 727 728 return transfer->len; 729 } 730 731 static int spi_imx_setup(struct spi_device *spi) 732 { 733 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); 734 int gpio = spi_imx->chipselect[spi->chip_select]; 735 736 dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__, 737 spi->mode, spi->bits_per_word, spi->max_speed_hz); 738 739 if (gpio >= 0) 740 gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1); 741 742 spi_imx_chipselect(spi, BITBANG_CS_INACTIVE); 743 744 return 0; 745 } 746 747 static void spi_imx_cleanup(struct spi_device *spi) 748 { 749 } 750 751 static int __devinit spi_imx_probe(struct platform_device *pdev) 752 { 753 struct device_node *np = pdev->dev.of_node; 754 const struct of_device_id *of_id = 755 of_match_device(spi_imx_dt_ids, &pdev->dev); 756 struct spi_imx_master *mxc_platform_info = 757 dev_get_platdata(&pdev->dev); 758 struct spi_master *master; 759 struct spi_imx_data *spi_imx; 760 struct resource *res; 761 int i, ret, num_cs; 762 763 if (!np && !mxc_platform_info) { 764 dev_err(&pdev->dev, "can't get the platform data\n"); 765 return -EINVAL; 766 } 767 768 ret = of_property_read_u32(np, "fsl,spi-num-chipselects", &num_cs); 769 if (ret < 0) { 770 if (mxc_platform_info) 771 num_cs = mxc_platform_info->num_chipselect; 772 else 773 return ret; 774 } 775 776 master = spi_alloc_master(&pdev->dev, 777 sizeof(struct spi_imx_data) + sizeof(int) * num_cs); 778 if (!master) 779 return -ENOMEM; 780 781 platform_set_drvdata(pdev, master); 782 783 master->bus_num = pdev->id; 784 master->num_chipselect = num_cs; 785 786 spi_imx = spi_master_get_devdata(master); 787 spi_imx->bitbang.master = spi_master_get(master); 788 789 for (i = 0; i < master->num_chipselect; i++) { 790 int cs_gpio = of_get_named_gpio(np, "cs-gpios", i); 791 if (cs_gpio < 0 && mxc_platform_info) 792 cs_gpio = mxc_platform_info->chipselect[i]; 793 794 spi_imx->chipselect[i] = cs_gpio; 795 if (cs_gpio < 0) 796 continue; 797 798 ret = gpio_request(spi_imx->chipselect[i], DRIVER_NAME); 799 if (ret) { 800 dev_err(&pdev->dev, "can't get cs gpios\n"); 801 goto out_gpio_free; 802 } 803 } 804 805 spi_imx->bitbang.chipselect = spi_imx_chipselect; 806 spi_imx->bitbang.setup_transfer = spi_imx_setupxfer; 807 spi_imx->bitbang.txrx_bufs = spi_imx_transfer; 808 spi_imx->bitbang.master->setup = spi_imx_setup; 809 spi_imx->bitbang.master->cleanup = spi_imx_cleanup; 810 spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; 811 812 init_completion(&spi_imx->xfer_done); 813 814 spi_imx->devtype_data = of_id ? of_id->data : 815 (struct spi_imx_devtype_data *) pdev->id_entry->driver_data; 816 817 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 818 if (!res) { 819 dev_err(&pdev->dev, "can't get platform resource\n"); 820 ret = -ENOMEM; 821 goto out_gpio_free; 822 } 823 824 if (!request_mem_region(res->start, resource_size(res), pdev->name)) { 825 dev_err(&pdev->dev, "request_mem_region failed\n"); 826 ret = -EBUSY; 827 goto out_gpio_free; 828 } 829 830 spi_imx->base = ioremap(res->start, resource_size(res)); 831 if (!spi_imx->base) { 832 ret = -EINVAL; 833 goto out_release_mem; 834 } 835 836 spi_imx->irq = platform_get_irq(pdev, 0); 837 if (spi_imx->irq < 0) { 838 ret = -EINVAL; 839 goto out_iounmap; 840 } 841 842 ret = request_irq(spi_imx->irq, spi_imx_isr, 0, DRIVER_NAME, spi_imx); 843 if (ret) { 844 dev_err(&pdev->dev, "can't get irq%d: %d\n", spi_imx->irq, ret); 845 goto out_iounmap; 846 } 847 848 spi_imx->clk = clk_get(&pdev->dev, NULL); 849 if (IS_ERR(spi_imx->clk)) { 850 dev_err(&pdev->dev, "unable to get clock\n"); 851 ret = PTR_ERR(spi_imx->clk); 852 goto out_free_irq; 853 } 854 855 clk_enable(spi_imx->clk); 856 spi_imx->spi_clk = clk_get_rate(spi_imx->clk); 857 858 spi_imx->devtype_data->reset(spi_imx); 859 860 spi_imx->devtype_data->intctrl(spi_imx, 0); 861 862 master->dev.of_node = pdev->dev.of_node; 863 ret = spi_bitbang_start(&spi_imx->bitbang); 864 if (ret) { 865 dev_err(&pdev->dev, "bitbang start failed with %d\n", ret); 866 goto out_clk_put; 867 } 868 869 dev_info(&pdev->dev, "probed\n"); 870 871 return ret; 872 873 out_clk_put: 874 clk_disable(spi_imx->clk); 875 clk_put(spi_imx->clk); 876 out_free_irq: 877 free_irq(spi_imx->irq, spi_imx); 878 out_iounmap: 879 iounmap(spi_imx->base); 880 out_release_mem: 881 release_mem_region(res->start, resource_size(res)); 882 out_gpio_free: 883 while (--i >= 0) { 884 if (spi_imx->chipselect[i] >= 0) 885 gpio_free(spi_imx->chipselect[i]); 886 } 887 spi_master_put(master); 888 kfree(master); 889 platform_set_drvdata(pdev, NULL); 890 return ret; 891 } 892 893 static int __devexit spi_imx_remove(struct platform_device *pdev) 894 { 895 struct spi_master *master = platform_get_drvdata(pdev); 896 struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 897 struct spi_imx_data *spi_imx = spi_master_get_devdata(master); 898 int i; 899 900 spi_bitbang_stop(&spi_imx->bitbang); 901 902 writel(0, spi_imx->base + MXC_CSPICTRL); 903 clk_disable(spi_imx->clk); 904 clk_put(spi_imx->clk); 905 free_irq(spi_imx->irq, spi_imx); 906 iounmap(spi_imx->base); 907 908 for (i = 0; i < master->num_chipselect; i++) 909 if (spi_imx->chipselect[i] >= 0) 910 gpio_free(spi_imx->chipselect[i]); 911 912 spi_master_put(master); 913 914 release_mem_region(res->start, resource_size(res)); 915 916 platform_set_drvdata(pdev, NULL); 917 918 return 0; 919 } 920 921 static struct platform_driver spi_imx_driver = { 922 .driver = { 923 .name = DRIVER_NAME, 924 .owner = THIS_MODULE, 925 .of_match_table = spi_imx_dt_ids, 926 }, 927 .id_table = spi_imx_devtype, 928 .probe = spi_imx_probe, 929 .remove = __devexit_p(spi_imx_remove), 930 }; 931 module_platform_driver(spi_imx_driver); 932 933 MODULE_DESCRIPTION("SPI Master Controller driver"); 934 MODULE_AUTHOR("Sascha Hauer, Pengutronix"); 935 MODULE_LICENSE("GPL"); 936