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added 2.6.29.6 aldebaran kernel
[nao-ulib.git] / kernel / 2.6.29.6-aldebaran-rt / drivers / spi / spi_mpc83xx.c
blobac0e3e4b3c543e480028d90829c7f5606b7fde71
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 */
31 struct 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. */
70 struct 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
106 struct 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
115 static inline void mpc83xx_spi_write_reg(__be32 __iomem * reg, u32 val)
116 {
117 out_be32(reg, val);
118 }
119
120 static inline u32 mpc83xx_spi_read_reg(__be32 __iomem * reg)
121 {
122 return in_be32(reg);
123 }
124
125 #define MPC83XX_SPI_RX_BUF(type) \
126 void 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) \
134 u32 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
145 MPC83XX_SPI_RX_BUF(u8)
146 MPC83XX_SPI_RX_BUF(u16)
147 MPC83XX_SPI_RX_BUF(u32)
148 MPC83XX_SPI_TX_BUF(u8)
149 MPC83XX_SPI_TX_BUF(u16)
150 MPC83XX_SPI_TX_BUF(u32)
151
152 static 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
192 static
193 int 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
302 static 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
346 static 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
420 static 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
486 irqreturn_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 }
525 static 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
543 static void mpc83xx_spi_cleanup(struct spi_device *spi)
544 {
545 kfree(spi->controller_state);
546 }
547
548 static 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
656 unreg_master:
657 destroy_workqueue(mpc83xx_spi->workqueue);
658 free_irq:
659 free_irq(mpc83xx_spi->irq, mpc83xx_spi);
660 unmap_io:
661 iounmap(mpc83xx_spi->base);
662 put_master:
663 spi_master_put(master);
664 free_master:
665 kfree(master);
666 err:
667 return ret;
668 }
669
670 static 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
688 MODULE_ALIAS("platform:mpc83xx_spi");
689 static 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
697 static int __init mpc83xx_spi_init(void)
698 {
699 return platform_driver_probe(&mpc83xx_spi_driver, mpc83xx_spi_probe);
700 }
701
702 static void __exit mpc83xx_spi_exit(void)
703 {
704 platform_driver_unregister(&mpc83xx_spi_driver);
705 }
706
707 module_init(mpc83xx_spi_init);
708 module_exit(mpc83xx_spi_exit);
709
710 MODULE_AUTHOR("Kumar Gala");
711 MODULE_DESCRIPTION("Simple MPC83xx SPI Driver");
712 MODULE_LICENSE("GPL");
Nao low-level kernelspace/userspace library that runs on our robots, Nao-Team HTWK