Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
1
fork

Configure Feed

Select the types of activity you want to include in your feed.

at v2.6.29-rc1 712 lines 18 kB view raw
1/* 2 * MPC83xx SPI controller driver. 3 * 4 * Maintainer: Kumar Gala 5 * 6 * Copyright (C) 2006 Polycom, Inc. 7 * 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms of the GNU General Public License as published by the 10 * Free Software Foundation; either version 2 of the License, or (at your 11 * option) any later version. 12 */ 13#include <linux/module.h> 14#include <linux/init.h> 15#include <linux/types.h> 16#include <linux/kernel.h> 17#include <linux/completion.h> 18#include <linux/interrupt.h> 19#include <linux/delay.h> 20#include <linux/irq.h> 21#include <linux/device.h> 22#include <linux/spi/spi.h> 23#include <linux/spi/spi_bitbang.h> 24#include <linux/platform_device.h> 25#include <linux/fsl_devices.h> 26 27#include <asm/irq.h> 28#include <asm/io.h> 29 30/* SPI Controller registers */ 31struct mpc83xx_spi_reg { 32 u8 res1[0x20]; 33 __be32 mode; 34 __be32 event; 35 __be32 mask; 36 __be32 command; 37 __be32 transmit; 38 __be32 receive; 39}; 40 41/* SPI Controller mode register definitions */ 42#define SPMODE_LOOP (1 << 30) 43#define SPMODE_CI_INACTIVEHIGH (1 << 29) 44#define SPMODE_CP_BEGIN_EDGECLK (1 << 28) 45#define SPMODE_DIV16 (1 << 27) 46#define SPMODE_REV (1 << 26) 47#define SPMODE_MS (1 << 25) 48#define SPMODE_ENABLE (1 << 24) 49#define SPMODE_LEN(x) ((x) << 20) 50#define SPMODE_PM(x) ((x) << 16) 51#define SPMODE_OP (1 << 14) 52#define SPMODE_CG(x) ((x) << 7) 53 54/* 55 * Default for SPI Mode: 56 * SPI MODE 0 (inactive low, phase middle, MSB, 8-bit length, slow clk 57 */ 58#define SPMODE_INIT_VAL (SPMODE_CI_INACTIVEHIGH | SPMODE_DIV16 | SPMODE_REV | \ 59 SPMODE_MS | SPMODE_LEN(7) | SPMODE_PM(0xf)) 60 61/* SPIE register values */ 62#define SPIE_NE 0x00000200 /* Not empty */ 63#define SPIE_NF 0x00000100 /* Not full */ 64 65/* SPIM register values */ 66#define SPIM_NE 0x00000200 /* Not empty */ 67#define SPIM_NF 0x00000100 /* Not full */ 68 69/* SPI Controller driver's private data. */ 70struct mpc83xx_spi { 71 struct mpc83xx_spi_reg __iomem *base; 72 73 /* rx & tx bufs from the spi_transfer */ 74 const void *tx; 75 void *rx; 76 77 /* functions to deal with different sized buffers */ 78 void (*get_rx) (u32 rx_data, struct mpc83xx_spi *); 79 u32(*get_tx) (struct mpc83xx_spi *); 80 81 unsigned int count; 82 int irq; 83 84 unsigned nsecs; /* (clock cycle time)/2 */ 85 86 u32 spibrg; /* SPIBRG input clock */ 87 u32 rx_shift; /* RX data reg shift when in qe mode */ 88 u32 tx_shift; /* TX data reg shift when in qe mode */ 89 90 bool qe_mode; 91 92 void (*activate_cs) (u8 cs, u8 polarity); 93 void (*deactivate_cs) (u8 cs, u8 polarity); 94 95 u8 busy; 96 97 struct workqueue_struct *workqueue; 98 struct work_struct work; 99 100 struct list_head queue; 101 spinlock_t lock; 102 103 struct completion done; 104}; 105 106struct spi_mpc83xx_cs { 107 /* functions to deal with different sized buffers */ 108 void (*get_rx) (u32 rx_data, struct mpc83xx_spi *); 109 u32 (*get_tx) (struct mpc83xx_spi *); 110 u32 rx_shift; /* RX data reg shift when in qe mode */ 111 u32 tx_shift; /* TX data reg shift when in qe mode */ 112 u32 hw_mode; /* Holds HW mode register settings */ 113}; 114 115static inline void mpc83xx_spi_write_reg(__be32 __iomem * reg, u32 val) 116{ 117 out_be32(reg, val); 118} 119 120static inline u32 mpc83xx_spi_read_reg(__be32 __iomem * reg) 121{ 122 return in_be32(reg); 123} 124 125#define MPC83XX_SPI_RX_BUF(type) \ 126void mpc83xx_spi_rx_buf_##type(u32 data, struct mpc83xx_spi *mpc83xx_spi) \ 127{ \ 128 type * rx = mpc83xx_spi->rx; \ 129 *rx++ = (type)(data >> mpc83xx_spi->rx_shift); \ 130 mpc83xx_spi->rx = rx; \ 131} 132 133#define MPC83XX_SPI_TX_BUF(type) \ 134u32 mpc83xx_spi_tx_buf_##type(struct mpc83xx_spi *mpc83xx_spi) \ 135{ \ 136 u32 data; \ 137 const type * tx = mpc83xx_spi->tx; \ 138 if (!tx) \ 139 return 0; \ 140 data = *tx++ << mpc83xx_spi->tx_shift; \ 141 mpc83xx_spi->tx = tx; \ 142 return data; \ 143} 144 145MPC83XX_SPI_RX_BUF(u8) 146MPC83XX_SPI_RX_BUF(u16) 147MPC83XX_SPI_RX_BUF(u32) 148MPC83XX_SPI_TX_BUF(u8) 149MPC83XX_SPI_TX_BUF(u16) 150MPC83XX_SPI_TX_BUF(u32) 151 152static void mpc83xx_spi_chipselect(struct spi_device *spi, int value) 153{ 154 struct mpc83xx_spi *mpc83xx_spi; 155 u8 pol = spi->mode & SPI_CS_HIGH ? 1 : 0; 156 struct spi_mpc83xx_cs *cs = spi->controller_state; 157 158 mpc83xx_spi = spi_master_get_devdata(spi->master); 159 160 if (value == BITBANG_CS_INACTIVE) { 161 if (mpc83xx_spi->deactivate_cs) 162 mpc83xx_spi->deactivate_cs(spi->chip_select, pol); 163 } 164 165 if (value == BITBANG_CS_ACTIVE) { 166 u32 regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode); 167 168 mpc83xx_spi->rx_shift = cs->rx_shift; 169 mpc83xx_spi->tx_shift = cs->tx_shift; 170 mpc83xx_spi->get_rx = cs->get_rx; 171 mpc83xx_spi->get_tx = cs->get_tx; 172 173 if (cs->hw_mode != regval) { 174 unsigned long flags; 175 void *tmp_ptr = &mpc83xx_spi->base->mode; 176 177 regval = cs->hw_mode; 178 /* Turn off IRQs locally to minimize time that 179 * SPI is disabled 180 */ 181 local_irq_save(flags); 182 /* Turn off SPI unit prior changing mode */ 183 mpc83xx_spi_write_reg(tmp_ptr, regval & ~SPMODE_ENABLE); 184 mpc83xx_spi_write_reg(tmp_ptr, regval); 185 local_irq_restore(flags); 186 } 187 if (mpc83xx_spi->activate_cs) 188 mpc83xx_spi->activate_cs(spi->chip_select, pol); 189 } 190} 191 192static 193int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) 194{ 195 struct mpc83xx_spi *mpc83xx_spi; 196 u32 regval; 197 u8 bits_per_word, pm; 198 u32 hz; 199 struct spi_mpc83xx_cs *cs = spi->controller_state; 200 201 mpc83xx_spi = spi_master_get_devdata(spi->master); 202 203 if (t) { 204 bits_per_word = t->bits_per_word; 205 hz = t->speed_hz; 206 } else { 207 bits_per_word = 0; 208 hz = 0; 209 } 210 211 /* spi_transfer level calls that work per-word */ 212 if (!bits_per_word) 213 bits_per_word = spi->bits_per_word; 214 215 /* Make sure its a bit width we support [4..16, 32] */ 216 if ((bits_per_word < 4) 217 || ((bits_per_word > 16) && (bits_per_word != 32))) 218 return -EINVAL; 219 220 if (!hz) 221 hz = spi->max_speed_hz; 222 223 cs->rx_shift = 0; 224 cs->tx_shift = 0; 225 if (bits_per_word <= 8) { 226 cs->get_rx = mpc83xx_spi_rx_buf_u8; 227 cs->get_tx = mpc83xx_spi_tx_buf_u8; 228 if (mpc83xx_spi->qe_mode) { 229 cs->rx_shift = 16; 230 cs->tx_shift = 24; 231 } 232 } else if (bits_per_word <= 16) { 233 cs->get_rx = mpc83xx_spi_rx_buf_u16; 234 cs->get_tx = mpc83xx_spi_tx_buf_u16; 235 if (mpc83xx_spi->qe_mode) { 236 cs->rx_shift = 16; 237 cs->tx_shift = 16; 238 } 239 } else if (bits_per_word <= 32) { 240 cs->get_rx = mpc83xx_spi_rx_buf_u32; 241 cs->get_tx = mpc83xx_spi_tx_buf_u32; 242 } else 243 return -EINVAL; 244 245 if (mpc83xx_spi->qe_mode && spi->mode & SPI_LSB_FIRST) { 246 cs->tx_shift = 0; 247 if (bits_per_word <= 8) 248 cs->rx_shift = 8; 249 else 250 cs->rx_shift = 0; 251 } 252 253 mpc83xx_spi->rx_shift = cs->rx_shift; 254 mpc83xx_spi->tx_shift = cs->tx_shift; 255 mpc83xx_spi->get_rx = cs->get_rx; 256 mpc83xx_spi->get_tx = cs->get_tx; 257 258 if (bits_per_word == 32) 259 bits_per_word = 0; 260 else 261 bits_per_word = bits_per_word - 1; 262 263 /* mask out bits we are going to set */ 264 cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16 265 | SPMODE_PM(0xF)); 266 267 cs->hw_mode |= SPMODE_LEN(bits_per_word); 268 269 if ((mpc83xx_spi->spibrg / hz) > 64) { 270 cs->hw_mode |= SPMODE_DIV16; 271 pm = mpc83xx_spi->spibrg / (hz * 64); 272 if (pm > 16) { 273 dev_err(&spi->dev, "Requested speed is too " 274 "low: %d Hz. Will use %d Hz instead.\n", 275 hz, mpc83xx_spi->spibrg / 1024); 276 pm = 16; 277 } 278 } else 279 pm = mpc83xx_spi->spibrg / (hz * 4); 280 if (pm) 281 pm--; 282 283 cs->hw_mode |= SPMODE_PM(pm); 284 regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode); 285 if (cs->hw_mode != regval) { 286 unsigned long flags; 287 void *tmp_ptr = &mpc83xx_spi->base->mode; 288 289 regval = cs->hw_mode; 290 /* Turn off IRQs locally to minimize time 291 * that SPI is disabled 292 */ 293 local_irq_save(flags); 294 /* Turn off SPI unit prior changing mode */ 295 mpc83xx_spi_write_reg(tmp_ptr, regval & ~SPMODE_ENABLE); 296 mpc83xx_spi_write_reg(tmp_ptr, regval); 297 local_irq_restore(flags); 298 } 299 return 0; 300} 301 302static int mpc83xx_spi_bufs(struct spi_device *spi, struct spi_transfer *t) 303{ 304 struct mpc83xx_spi *mpc83xx_spi; 305 u32 word, len, bits_per_word; 306 307 mpc83xx_spi = spi_master_get_devdata(spi->master); 308 309 mpc83xx_spi->tx = t->tx_buf; 310 mpc83xx_spi->rx = t->rx_buf; 311 bits_per_word = spi->bits_per_word; 312 if (t->bits_per_word) 313 bits_per_word = t->bits_per_word; 314 len = t->len; 315 if (bits_per_word > 8) { 316 /* invalid length? */ 317 if (len & 1) 318 return -EINVAL; 319 len /= 2; 320 } 321 if (bits_per_word > 16) { 322 /* invalid length? */ 323 if (len & 1) 324 return -EINVAL; 325 len /= 2; 326 } 327 mpc83xx_spi->count = len; 328 329 INIT_COMPLETION(mpc83xx_spi->done); 330 331 /* enable rx ints */ 332 mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, SPIM_NE); 333 334 /* transmit word */ 335 word = mpc83xx_spi->get_tx(mpc83xx_spi); 336 mpc83xx_spi_write_reg(&mpc83xx_spi->base->transmit, word); 337 338 wait_for_completion(&mpc83xx_spi->done); 339 340 /* disable rx ints */ 341 mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, 0); 342 343 return mpc83xx_spi->count; 344} 345 346static void mpc83xx_spi_work(struct work_struct *work) 347{ 348 struct mpc83xx_spi *mpc83xx_spi = 349 container_of(work, struct mpc83xx_spi, work); 350 351 spin_lock_irq(&mpc83xx_spi->lock); 352 mpc83xx_spi->busy = 1; 353 while (!list_empty(&mpc83xx_spi->queue)) { 354 struct spi_message *m; 355 struct spi_device *spi; 356 struct spi_transfer *t = NULL; 357 unsigned cs_change; 358 int status, nsecs = 50; 359 360 m = container_of(mpc83xx_spi->queue.next, 361 struct spi_message, queue); 362 list_del_init(&m->queue); 363 spin_unlock_irq(&mpc83xx_spi->lock); 364 365 spi = m->spi; 366 cs_change = 1; 367 status = 0; 368 list_for_each_entry(t, &m->transfers, transfer_list) { 369 if (t->bits_per_word || t->speed_hz) { 370 /* Don't allow changes if CS is active */ 371 status = -EINVAL; 372 373 if (cs_change) 374 status = mpc83xx_spi_setup_transfer(spi, t); 375 if (status < 0) 376 break; 377 } 378 379 if (cs_change) 380 mpc83xx_spi_chipselect(spi, BITBANG_CS_ACTIVE); 381 cs_change = t->cs_change; 382 if (t->len) 383 status = mpc83xx_spi_bufs(spi, t); 384 if (status) { 385 status = -EMSGSIZE; 386 break; 387 } 388 m->actual_length += t->len; 389 390 if (t->delay_usecs) 391 udelay(t->delay_usecs); 392 393 if (cs_change) { 394 ndelay(nsecs); 395 mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE); 396 ndelay(nsecs); 397 } 398 } 399 400 m->status = status; 401 m->complete(m->context); 402 403 if (status || !cs_change) { 404 ndelay(nsecs); 405 mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE); 406 } 407 408 mpc83xx_spi_setup_transfer(spi, NULL); 409 410 spin_lock_irq(&mpc83xx_spi->lock); 411 } 412 mpc83xx_spi->busy = 0; 413 spin_unlock_irq(&mpc83xx_spi->lock); 414} 415 416/* the spi->mode bits understood by this driver: */ 417#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \ 418 | SPI_LSB_FIRST | SPI_LOOP) 419 420static int mpc83xx_spi_setup(struct spi_device *spi) 421{ 422 struct mpc83xx_spi *mpc83xx_spi; 423 int retval; 424 u32 hw_mode; 425 struct spi_mpc83xx_cs *cs = spi->controller_state; 426 427 if (spi->mode & ~MODEBITS) { 428 dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n", 429 spi->mode & ~MODEBITS); 430 return -EINVAL; 431 } 432 433 if (!spi->max_speed_hz) 434 return -EINVAL; 435 436 if (!cs) { 437 cs = kzalloc(sizeof *cs, GFP_KERNEL); 438 if (!cs) 439 return -ENOMEM; 440 spi->controller_state = cs; 441 } 442 mpc83xx_spi = spi_master_get_devdata(spi->master); 443 444 if (!spi->bits_per_word) 445 spi->bits_per_word = 8; 446 447 hw_mode = cs->hw_mode; /* Save orginal settings */ 448 cs->hw_mode = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode); 449 /* mask out bits we are going to set */ 450 cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH 451 | SPMODE_REV | SPMODE_LOOP); 452 453 if (spi->mode & SPI_CPHA) 454 cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK; 455 if (spi->mode & SPI_CPOL) 456 cs->hw_mode |= SPMODE_CI_INACTIVEHIGH; 457 if (!(spi->mode & SPI_LSB_FIRST)) 458 cs->hw_mode |= SPMODE_REV; 459 if (spi->mode & SPI_LOOP) 460 cs->hw_mode |= SPMODE_LOOP; 461 462 retval = mpc83xx_spi_setup_transfer(spi, NULL); 463 if (retval < 0) { 464 cs->hw_mode = hw_mode; /* Restore settings */ 465 return retval; 466 } 467 468 dev_dbg(&spi->dev, "%s, mode %d, %u bits/w, %u Hz\n", 469 __func__, spi->mode & (SPI_CPOL | SPI_CPHA), 470 spi->bits_per_word, spi->max_speed_hz); 471#if 0 /* Don't think this is needed */ 472 /* NOTE we _need_ to call chipselect() early, ideally with adapter 473 * setup, unless the hardware defaults cooperate to avoid confusion 474 * between normal (active low) and inverted chipselects. 475 */ 476 477 /* deselect chip (low or high) */ 478 spin_lock(&mpc83xx_spi->lock); 479 if (!mpc83xx_spi->busy) 480 mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE); 481 spin_unlock(&mpc83xx_spi->lock); 482#endif 483 return 0; 484} 485 486irqreturn_t mpc83xx_spi_irq(s32 irq, void *context_data) 487{ 488 struct mpc83xx_spi *mpc83xx_spi = context_data; 489 u32 event; 490 irqreturn_t ret = IRQ_NONE; 491 492 /* Get interrupt events(tx/rx) */ 493 event = mpc83xx_spi_read_reg(&mpc83xx_spi->base->event); 494 495 /* We need handle RX first */ 496 if (event & SPIE_NE) { 497 u32 rx_data = mpc83xx_spi_read_reg(&mpc83xx_spi->base->receive); 498 499 if (mpc83xx_spi->rx) 500 mpc83xx_spi->get_rx(rx_data, mpc83xx_spi); 501 502 ret = IRQ_HANDLED; 503 } 504 505 if ((event & SPIE_NF) == 0) 506 /* spin until TX is done */ 507 while (((event = 508 mpc83xx_spi_read_reg(&mpc83xx_spi->base->event)) & 509 SPIE_NF) == 0) 510 cpu_relax(); 511 512 mpc83xx_spi->count -= 1; 513 if (mpc83xx_spi->count) { 514 u32 word = mpc83xx_spi->get_tx(mpc83xx_spi); 515 mpc83xx_spi_write_reg(&mpc83xx_spi->base->transmit, word); 516 } else { 517 complete(&mpc83xx_spi->done); 518 } 519 520 /* Clear the events */ 521 mpc83xx_spi_write_reg(&mpc83xx_spi->base->event, event); 522 523 return ret; 524} 525static int mpc83xx_spi_transfer(struct spi_device *spi, 526 struct spi_message *m) 527{ 528 struct mpc83xx_spi *mpc83xx_spi = spi_master_get_devdata(spi->master); 529 unsigned long flags; 530 531 m->actual_length = 0; 532 m->status = -EINPROGRESS; 533 534 spin_lock_irqsave(&mpc83xx_spi->lock, flags); 535 list_add_tail(&m->queue, &mpc83xx_spi->queue); 536 queue_work(mpc83xx_spi->workqueue, &mpc83xx_spi->work); 537 spin_unlock_irqrestore(&mpc83xx_spi->lock, flags); 538 539 return 0; 540} 541 542 543static void mpc83xx_spi_cleanup(struct spi_device *spi) 544{ 545 kfree(spi->controller_state); 546} 547 548static int __init mpc83xx_spi_probe(struct platform_device *dev) 549{ 550 struct spi_master *master; 551 struct mpc83xx_spi *mpc83xx_spi; 552 struct fsl_spi_platform_data *pdata; 553 struct resource *r; 554 u32 regval; 555 int ret = 0; 556 557 /* Get resources(memory, IRQ) associated with the device */ 558 master = spi_alloc_master(&dev->dev, sizeof(struct mpc83xx_spi)); 559 560 if (master == NULL) { 561 ret = -ENOMEM; 562 goto err; 563 } 564 565 platform_set_drvdata(dev, master); 566 pdata = dev->dev.platform_data; 567 568 if (pdata == NULL) { 569 ret = -ENODEV; 570 goto free_master; 571 } 572 573 r = platform_get_resource(dev, IORESOURCE_MEM, 0); 574 if (r == NULL) { 575 ret = -ENODEV; 576 goto free_master; 577 } 578 master->setup = mpc83xx_spi_setup; 579 master->transfer = mpc83xx_spi_transfer; 580 master->cleanup = mpc83xx_spi_cleanup; 581 582 mpc83xx_spi = spi_master_get_devdata(master); 583 mpc83xx_spi->activate_cs = pdata->activate_cs; 584 mpc83xx_spi->deactivate_cs = pdata->deactivate_cs; 585 mpc83xx_spi->qe_mode = pdata->qe_mode; 586 mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u8; 587 mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u8; 588 mpc83xx_spi->spibrg = pdata->sysclk; 589 590 mpc83xx_spi->rx_shift = 0; 591 mpc83xx_spi->tx_shift = 0; 592 if (mpc83xx_spi->qe_mode) { 593 mpc83xx_spi->rx_shift = 16; 594 mpc83xx_spi->tx_shift = 24; 595 } 596 597 init_completion(&mpc83xx_spi->done); 598 599 mpc83xx_spi->base = ioremap(r->start, r->end - r->start + 1); 600 if (mpc83xx_spi->base == NULL) { 601 ret = -ENOMEM; 602 goto put_master; 603 } 604 605 mpc83xx_spi->irq = platform_get_irq(dev, 0); 606 607 if (mpc83xx_spi->irq < 0) { 608 ret = -ENXIO; 609 goto unmap_io; 610 } 611 612 /* Register for SPI Interrupt */ 613 ret = request_irq(mpc83xx_spi->irq, mpc83xx_spi_irq, 614 0, "mpc83xx_spi", mpc83xx_spi); 615 616 if (ret != 0) 617 goto unmap_io; 618 619 master->bus_num = pdata->bus_num; 620 master->num_chipselect = pdata->max_chipselect; 621 622 /* SPI controller initializations */ 623 mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0); 624 mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, 0); 625 mpc83xx_spi_write_reg(&mpc83xx_spi->base->command, 0); 626 mpc83xx_spi_write_reg(&mpc83xx_spi->base->event, 0xffffffff); 627 628 /* Enable SPI interface */ 629 regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE; 630 if (pdata->qe_mode) 631 regval |= SPMODE_OP; 632 633 mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval); 634 spin_lock_init(&mpc83xx_spi->lock); 635 init_completion(&mpc83xx_spi->done); 636 INIT_WORK(&mpc83xx_spi->work, mpc83xx_spi_work); 637 INIT_LIST_HEAD(&mpc83xx_spi->queue); 638 639 mpc83xx_spi->workqueue = create_singlethread_workqueue( 640 master->dev.parent->bus_id); 641 if (mpc83xx_spi->workqueue == NULL) { 642 ret = -EBUSY; 643 goto free_irq; 644 } 645 646 ret = spi_register_master(master); 647 if (ret < 0) 648 goto unreg_master; 649 650 printk(KERN_INFO 651 "%s: MPC83xx SPI Controller driver at 0x%p (irq = %d)\n", 652 dev->dev.bus_id, mpc83xx_spi->base, mpc83xx_spi->irq); 653 654 return ret; 655 656unreg_master: 657 destroy_workqueue(mpc83xx_spi->workqueue); 658free_irq: 659 free_irq(mpc83xx_spi->irq, mpc83xx_spi); 660unmap_io: 661 iounmap(mpc83xx_spi->base); 662put_master: 663 spi_master_put(master); 664free_master: 665 kfree(master); 666err: 667 return ret; 668} 669 670static int __exit mpc83xx_spi_remove(struct platform_device *dev) 671{ 672 struct mpc83xx_spi *mpc83xx_spi; 673 struct spi_master *master; 674 675 master = platform_get_drvdata(dev); 676 mpc83xx_spi = spi_master_get_devdata(master); 677 678 flush_workqueue(mpc83xx_spi->workqueue); 679 destroy_workqueue(mpc83xx_spi->workqueue); 680 spi_unregister_master(master); 681 682 free_irq(mpc83xx_spi->irq, mpc83xx_spi); 683 iounmap(mpc83xx_spi->base); 684 685 return 0; 686} 687 688MODULE_ALIAS("platform:mpc83xx_spi"); 689static struct platform_driver mpc83xx_spi_driver = { 690 .remove = __exit_p(mpc83xx_spi_remove), 691 .driver = { 692 .name = "mpc83xx_spi", 693 .owner = THIS_MODULE, 694 }, 695}; 696 697static int __init mpc83xx_spi_init(void) 698{ 699 return platform_driver_probe(&mpc83xx_spi_driver, mpc83xx_spi_probe); 700} 701 702static void __exit mpc83xx_spi_exit(void) 703{ 704 platform_driver_unregister(&mpc83xx_spi_driver); 705} 706 707module_init(mpc83xx_spi_init); 708module_exit(mpc83xx_spi_exit); 709 710MODULE_AUTHOR("Kumar Gala"); 711MODULE_DESCRIPTION("Simple MPC83xx SPI Driver"); 712MODULE_LICENSE("GPL");