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mm: vmscan: fix force-scanning small targets without swap
[linux-2.6.git] / drivers / spi / spi-fsl-espi.c
blob54e499d5f92cb043d805517db43983def2d52b01
1 /*
2 * Freescale eSPI controller driver.
3 *
4 * Copyright 2010 Freescale Semiconductor, Inc.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; either version 2 of the License, or (at your
9 * option) any later version.
10 */
11 #include <linux/module.h>
12 #include <linux/delay.h>
13 #include <linux/irq.h>
14 #include <linux/spi/spi.h>
15 #include <linux/platform_device.h>
16 #include <linux/fsl_devices.h>
17 #include <linux/mm.h>
18 #include <linux/of.h>
19 #include <linux/of_platform.h>
20 #include <linux/of_spi.h>
21 #include <linux/interrupt.h>
22 #include <linux/err.h>
23 #include <sysdev/fsl_soc.h>
24
25 #include "spi-fsl-lib.h"
26
27 /* eSPI Controller registers */
28 struct fsl_espi_reg {
29 __be32 mode; /* 0x000 - eSPI mode register */
30 __be32 event; /* 0x004 - eSPI event register */
31 __be32 mask; /* 0x008 - eSPI mask register */
32 __be32 command; /* 0x00c - eSPI command register */
33 __be32 transmit; /* 0x010 - eSPI transmit FIFO access register*/
34 __be32 receive; /* 0x014 - eSPI receive FIFO access register*/
35 u8 res[8]; /* 0x018 - 0x01c reserved */
36 __be32 csmode[4]; /* 0x020 - 0x02c eSPI cs mode register */
37 };
38
39 struct fsl_espi_transfer {
40 const void *tx_buf;
41 void *rx_buf;
42 unsigned len;
43 unsigned n_tx;
44 unsigned n_rx;
45 unsigned actual_length;
46 int status;
47 };
48
49 /* eSPI Controller mode register definitions */
50 #define SPMODE_ENABLE (1 << 31)
51 #define SPMODE_LOOP (1 << 30)
52 #define SPMODE_TXTHR(x) ((x) << 8)
53 #define SPMODE_RXTHR(x) ((x) << 0)
54
55 /* eSPI Controller CS mode register definitions */
56 #define CSMODE_CI_INACTIVEHIGH (1 << 31)
57 #define CSMODE_CP_BEGIN_EDGECLK (1 << 30)
58 #define CSMODE_REV (1 << 29)
59 #define CSMODE_DIV16 (1 << 28)
60 #define CSMODE_PM(x) ((x) << 24)
61 #define CSMODE_POL_1 (1 << 20)
62 #define CSMODE_LEN(x) ((x) << 16)
63 #define CSMODE_BEF(x) ((x) << 12)
64 #define CSMODE_AFT(x) ((x) << 8)
65 #define CSMODE_CG(x) ((x) << 3)
66
67 /* Default mode/csmode for eSPI controller */
68 #define SPMODE_INIT_VAL (SPMODE_TXTHR(4) | SPMODE_RXTHR(3))
69 #define CSMODE_INIT_VAL (CSMODE_POL_1 | CSMODE_BEF(0) \
70 | CSMODE_AFT(0) | CSMODE_CG(1))
71
72 /* SPIE register values */
73 #define SPIE_NE 0x00000200 /* Not empty */
74 #define SPIE_NF 0x00000100 /* Not full */
75
76 /* SPIM register values */
77 #define SPIM_NE 0x00000200 /* Not empty */
78 #define SPIM_NF 0x00000100 /* Not full */
79 #define SPIE_RXCNT(reg) ((reg >> 24) & 0x3F)
80 #define SPIE_TXCNT(reg) ((reg >> 16) & 0x3F)
81
82 /* SPCOM register values */
83 #define SPCOM_CS(x) ((x) << 30)
84 #define SPCOM_TRANLEN(x) ((x) << 0)
85 #define SPCOM_TRANLEN_MAX 0xFFFF /* Max transaction length */
86
87 static void fsl_espi_change_mode(struct spi_device *spi)
88 {
89 struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
90 struct spi_mpc8xxx_cs *cs = spi->controller_state;
91 struct fsl_espi_reg *reg_base = mspi->reg_base;
92 __be32 __iomem *mode = &reg_base->csmode[spi->chip_select];
93 __be32 __iomem *espi_mode = &reg_base->mode;
94 u32 tmp;
95 unsigned long flags;
96
97 /* Turn off IRQs locally to minimize time that SPI is disabled. */
98 local_irq_save(flags);
99
100 /* Turn off SPI unit prior changing mode */
101 tmp = mpc8xxx_spi_read_reg(espi_mode);
102 mpc8xxx_spi_write_reg(espi_mode, tmp & ~SPMODE_ENABLE);
103 mpc8xxx_spi_write_reg(mode, cs->hw_mode);
104 mpc8xxx_spi_write_reg(espi_mode, tmp);
105
106 local_irq_restore(flags);
107 }
108
109 static u32 fsl_espi_tx_buf_lsb(struct mpc8xxx_spi *mpc8xxx_spi)
110 {
111 u32 data;
112 u16 data_h;
113 u16 data_l;
114 const u32 *tx = mpc8xxx_spi->tx;
115
116 if (!tx)
117 return 0;
118
119 data = *tx++ << mpc8xxx_spi->tx_shift;
120 data_l = data & 0xffff;
121 data_h = (data >> 16) & 0xffff;
122 swab16s(&data_l);
123 swab16s(&data_h);
124 data = data_h | data_l;
125
126 mpc8xxx_spi->tx = tx;
127 return data;
128 }
129
130 static int fsl_espi_setup_transfer(struct spi_device *spi,
131 struct spi_transfer *t)
132 {
133 struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
134 int bits_per_word = 0;
135 u8 pm;
136 u32 hz = 0;
137 struct spi_mpc8xxx_cs *cs = spi->controller_state;
138
139 if (t) {
140 bits_per_word = t->bits_per_word;
141 hz = t->speed_hz;
142 }
143
144 /* spi_transfer level calls that work per-word */
145 if (!bits_per_word)
146 bits_per_word = spi->bits_per_word;
147
148 /* Make sure its a bit width we support [4..16] */
149 if ((bits_per_word < 4) || (bits_per_word > 16))
150 return -EINVAL;
151
152 if (!hz)
153 hz = spi->max_speed_hz;
154
155 cs->rx_shift = 0;
156 cs->tx_shift = 0;
157 cs->get_rx = mpc8xxx_spi_rx_buf_u32;
158 cs->get_tx = mpc8xxx_spi_tx_buf_u32;
159 if (bits_per_word <= 8) {
160 cs->rx_shift = 8 - bits_per_word;
161 } else if (bits_per_word <= 16) {
162 cs->rx_shift = 16 - bits_per_word;
163 if (spi->mode & SPI_LSB_FIRST)
164 cs->get_tx = fsl_espi_tx_buf_lsb;
165 } else {
166 return -EINVAL;
167 }
168
169 mpc8xxx_spi->rx_shift = cs->rx_shift;
170 mpc8xxx_spi->tx_shift = cs->tx_shift;
171 mpc8xxx_spi->get_rx = cs->get_rx;
172 mpc8xxx_spi->get_tx = cs->get_tx;
173
174 bits_per_word = bits_per_word - 1;
175
176 /* mask out bits we are going to set */
177 cs->hw_mode &= ~(CSMODE_LEN(0xF) | CSMODE_DIV16 | CSMODE_PM(0xF));
178
179 cs->hw_mode |= CSMODE_LEN(bits_per_word);
180
181 if ((mpc8xxx_spi->spibrg / hz) > 64) {
182 cs->hw_mode |= CSMODE_DIV16;
183 pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
184
185 WARN_ONCE(pm > 16, "%s: Requested speed is too low: %d Hz. "
186 "Will use %d Hz instead.\n", dev_name(&spi->dev),
187 hz, mpc8xxx_spi->spibrg / 1024);
188 if (pm > 16)
189 pm = 16;
190 } else {
191 pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
192 }
193 if (pm)
194 pm--;
195
196 cs->hw_mode |= CSMODE_PM(pm);
197
198 fsl_espi_change_mode(spi);
199 return 0;
200 }
201
202 static int fsl_espi_cpu_bufs(struct mpc8xxx_spi *mspi, struct spi_transfer *t,
203 unsigned int len)
204 {
205 u32 word;
206 struct fsl_espi_reg *reg_base = mspi->reg_base;
207
208 mspi->count = len;
209
210 /* enable rx ints */
211 mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
212
213 /* transmit word */
214 word = mspi->get_tx(mspi);
215 mpc8xxx_spi_write_reg(&reg_base->transmit, word);
216
217 return 0;
218 }
219
220 static int fsl_espi_bufs(struct spi_device *spi, struct spi_transfer *t)
221 {
222 struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
223 struct fsl_espi_reg *reg_base = mpc8xxx_spi->reg_base;
224 unsigned int len = t->len;
225 u8 bits_per_word;
226 int ret;
227
228 bits_per_word = spi->bits_per_word;
229 if (t->bits_per_word)
230 bits_per_word = t->bits_per_word;
231
232 mpc8xxx_spi->len = t->len;
233 len = roundup(len, 4) / 4;
234
235 mpc8xxx_spi->tx = t->tx_buf;
236 mpc8xxx_spi->rx = t->rx_buf;
237
238 INIT_COMPLETION(mpc8xxx_spi->done);
239
240 /* Set SPCOM[CS] and SPCOM[TRANLEN] field */
241 if ((t->len - 1) > SPCOM_TRANLEN_MAX) {
242 dev_err(mpc8xxx_spi->dev, "Transaction length (%d)"
243 " beyond the SPCOM[TRANLEN] field\n", t->len);
244 return -EINVAL;
245 }
246 mpc8xxx_spi_write_reg(&reg_base->command,
247 (SPCOM_CS(spi->chip_select) | SPCOM_TRANLEN(t->len - 1)));
248
249 ret = fsl_espi_cpu_bufs(mpc8xxx_spi, t, len);
250 if (ret)
251 return ret;
252
253 wait_for_completion(&mpc8xxx_spi->done);
254
255 /* disable rx ints */
256 mpc8xxx_spi_write_reg(&reg_base->mask, 0);
257
258 return mpc8xxx_spi->count;
259 }
260
261 static inline void fsl_espi_addr2cmd(unsigned int addr, u8 *cmd)
262 {
263 if (cmd) {
264 cmd[1] = (u8)(addr >> 16);
265 cmd[2] = (u8)(addr >> 8);
266 cmd[3] = (u8)(addr >> 0);
267 }
268 }
269
270 static inline unsigned int fsl_espi_cmd2addr(u8 *cmd)
271 {
272 if (cmd)
273 return cmd[1] << 16 | cmd[2] << 8 | cmd[3] << 0;
274
275 return 0;
276 }
277
278 static void fsl_espi_do_trans(struct spi_message *m,
279 struct fsl_espi_transfer *tr)
280 {
281 struct spi_device *spi = m->spi;
282 struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
283 struct fsl_espi_transfer *espi_trans = tr;
284 struct spi_message message;
285 struct spi_transfer *t, *first, trans;
286 int status = 0;
287
288 spi_message_init(&message);
289 memset(&trans, 0, sizeof(trans));
290
291 first = list_first_entry(&m->transfers, struct spi_transfer,
292 transfer_list);
293 list_for_each_entry(t, &m->transfers, transfer_list) {
294 if ((first->bits_per_word != t->bits_per_word) ||
295 (first->speed_hz != t->speed_hz)) {
296 espi_trans->status = -EINVAL;
297 dev_err(mspi->dev, "bits_per_word/speed_hz should be"
298 " same for the same SPI transfer\n");
299 return;
300 }
301
302 trans.speed_hz = t->speed_hz;
303 trans.bits_per_word = t->bits_per_word;
304 trans.delay_usecs = max(first->delay_usecs, t->delay_usecs);
305 }
306
307 trans.len = espi_trans->len;
308 trans.tx_buf = espi_trans->tx_buf;
309 trans.rx_buf = espi_trans->rx_buf;
310 spi_message_add_tail(&trans, &message);
311
312 list_for_each_entry(t, &message.transfers, transfer_list) {
313 if (t->bits_per_word || t->speed_hz) {
314 status = -EINVAL;
315
316 status = fsl_espi_setup_transfer(spi, t);
317 if (status < 0)
318 break;
319 }
320
321 if (t->len)
322 status = fsl_espi_bufs(spi, t);
323
324 if (status) {
325 status = -EMSGSIZE;
326 break;
327 }
328
329 if (t->delay_usecs)
330 udelay(t->delay_usecs);
331 }
332
333 espi_trans->status = status;
334 fsl_espi_setup_transfer(spi, NULL);
335 }
336
337 static void fsl_espi_cmd_trans(struct spi_message *m,
338 struct fsl_espi_transfer *trans, u8 *rx_buff)
339 {
340 struct spi_transfer *t;
341 u8 *local_buf;
342 int i = 0;
343 struct fsl_espi_transfer *espi_trans = trans;
344
345 local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
346 if (!local_buf) {
347 espi_trans->status = -ENOMEM;
348 return;
349 }
350
351 list_for_each_entry(t, &m->transfers, transfer_list) {
352 if (t->tx_buf) {
353 memcpy(local_buf + i, t->tx_buf, t->len);
354 i += t->len;
355 }
356 }
357
358 espi_trans->tx_buf = local_buf;
359 espi_trans->rx_buf = local_buf + espi_trans->n_tx;
360 fsl_espi_do_trans(m, espi_trans);
361
362 espi_trans->actual_length = espi_trans->len;
363 kfree(local_buf);
364 }
365
366 static void fsl_espi_rw_trans(struct spi_message *m,
367 struct fsl_espi_transfer *trans, u8 *rx_buff)
368 {
369 struct fsl_espi_transfer *espi_trans = trans;
370 unsigned int n_tx = espi_trans->n_tx;
371 unsigned int n_rx = espi_trans->n_rx;
372 struct spi_transfer *t;
373 u8 *local_buf;
374 u8 *rx_buf = rx_buff;
375 unsigned int trans_len;
376 unsigned int addr;
377 int i, pos, loop;
378
379 local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
380 if (!local_buf) {
381 espi_trans->status = -ENOMEM;
382 return;
383 }
384
385 for (pos = 0, loop = 0; pos < n_rx; pos += trans_len, loop++) {
386 trans_len = n_rx - pos;
387 if (trans_len > SPCOM_TRANLEN_MAX - n_tx)
388 trans_len = SPCOM_TRANLEN_MAX - n_tx;
389
390 i = 0;
391 list_for_each_entry(t, &m->transfers, transfer_list) {
392 if (t->tx_buf) {
393 memcpy(local_buf + i, t->tx_buf, t->len);
394 i += t->len;
395 }
396 }
397
398 if (pos > 0) {
399 addr = fsl_espi_cmd2addr(local_buf);
400 addr += pos;
401 fsl_espi_addr2cmd(addr, local_buf);
402 }
403
404 espi_trans->n_tx = n_tx;
405 espi_trans->n_rx = trans_len;
406 espi_trans->len = trans_len + n_tx;
407 espi_trans->tx_buf = local_buf;
408 espi_trans->rx_buf = local_buf + n_tx;
409 fsl_espi_do_trans(m, espi_trans);
410
411 memcpy(rx_buf + pos, espi_trans->rx_buf + n_tx, trans_len);
412
413 if (loop > 0)
414 espi_trans->actual_length += espi_trans->len - n_tx;
415 else
416 espi_trans->actual_length += espi_trans->len;
417 }
418
419 kfree(local_buf);
420 }
421
422 static void fsl_espi_do_one_msg(struct spi_message *m)
423 {
424 struct spi_transfer *t;
425 u8 *rx_buf = NULL;
426 unsigned int n_tx = 0;
427 unsigned int n_rx = 0;
428 struct fsl_espi_transfer espi_trans;
429
430 list_for_each_entry(t, &m->transfers, transfer_list) {
431 if (t->tx_buf)
432 n_tx += t->len;
433 if (t->rx_buf) {
434 n_rx += t->len;
435 rx_buf = t->rx_buf;
436 }
437 }
438
439 espi_trans.n_tx = n_tx;
440 espi_trans.n_rx = n_rx;
441 espi_trans.len = n_tx + n_rx;
442 espi_trans.actual_length = 0;
443 espi_trans.status = 0;
444
445 if (!rx_buf)
446 fsl_espi_cmd_trans(m, &espi_trans, NULL);
447 else
448 fsl_espi_rw_trans(m, &espi_trans, rx_buf);
449
450 m->actual_length = espi_trans.actual_length;
451 m->status = espi_trans.status;
452 m->complete(m->context);
453 }
454
455 static int fsl_espi_setup(struct spi_device *spi)
456 {
457 struct mpc8xxx_spi *mpc8xxx_spi;
458 struct fsl_espi_reg *reg_base;
459 int retval;
460 u32 hw_mode;
461 u32 loop_mode;
462 struct spi_mpc8xxx_cs *cs = spi->controller_state;
463
464 if (!spi->max_speed_hz)
465 return -EINVAL;
466
467 if (!cs) {
468 cs = kzalloc(sizeof *cs, GFP_KERNEL);
469 if (!cs)
470 return -ENOMEM;
471 spi->controller_state = cs;
472 }
473
474 mpc8xxx_spi = spi_master_get_devdata(spi->master);
475 reg_base = mpc8xxx_spi->reg_base;
476
477 hw_mode = cs->hw_mode; /* Save original settings */
478 cs->hw_mode = mpc8xxx_spi_read_reg(
479 &reg_base->csmode[spi->chip_select]);
480 /* mask out bits we are going to set */
481 cs->hw_mode &= ~(CSMODE_CP_BEGIN_EDGECLK | CSMODE_CI_INACTIVEHIGH
482 | CSMODE_REV);
483
484 if (spi->mode & SPI_CPHA)
485 cs->hw_mode |= CSMODE_CP_BEGIN_EDGECLK;
486 if (spi->mode & SPI_CPOL)
487 cs->hw_mode |= CSMODE_CI_INACTIVEHIGH;
488 if (!(spi->mode & SPI_LSB_FIRST))
489 cs->hw_mode |= CSMODE_REV;
490
491 /* Handle the loop mode */
492 loop_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
493 loop_mode &= ~SPMODE_LOOP;
494 if (spi->mode & SPI_LOOP)
495 loop_mode |= SPMODE_LOOP;
496 mpc8xxx_spi_write_reg(&reg_base->mode, loop_mode);
497
498 retval = fsl_espi_setup_transfer(spi, NULL);
499 if (retval < 0) {
500 cs->hw_mode = hw_mode; /* Restore settings */
501 return retval;
502 }
503 return 0;
504 }
505
506 void fsl_espi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
507 {
508 struct fsl_espi_reg *reg_base = mspi->reg_base;
509
510 /* We need handle RX first */
511 if (events & SPIE_NE) {
512 u32 rx_data, tmp;
513 u8 rx_data_8;
514
515 /* Spin until RX is done */
516 while (SPIE_RXCNT(events) < min(4, mspi->len)) {
517 cpu_relax();
518 events = mpc8xxx_spi_read_reg(&reg_base->event);
519 }
520
521 if (mspi->len >= 4) {
522 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
523 } else {
524 tmp = mspi->len;
525 rx_data = 0;
526 while (tmp--) {
527 rx_data_8 = in_8((u8 *)&reg_base->receive);
528 rx_data |= (rx_data_8 << (tmp * 8));
529 }
530
531 rx_data <<= (4 - mspi->len) * 8;
532 }
533
534 mspi->len -= 4;
535
536 if (mspi->rx)
537 mspi->get_rx(rx_data, mspi);
538 }
539
540 if (!(events & SPIE_NF)) {
541 int ret;
542
543 /* spin until TX is done */
544 ret = spin_event_timeout(((events = mpc8xxx_spi_read_reg(
545 &reg_base->event)) & SPIE_NF) == 0, 1000, 0);
546 if (!ret) {
547 dev_err(mspi->dev, "tired waiting for SPIE_NF\n");
548 return;
549 }
550 }
551
552 /* Clear the events */
553 mpc8xxx_spi_write_reg(&reg_base->event, events);
554
555 mspi->count -= 1;
556 if (mspi->count) {
557 u32 word = mspi->get_tx(mspi);
558
559 mpc8xxx_spi_write_reg(&reg_base->transmit, word);
560 } else {
561 complete(&mspi->done);
562 }
563 }
564
565 static irqreturn_t fsl_espi_irq(s32 irq, void *context_data)
566 {
567 struct mpc8xxx_spi *mspi = context_data;
568 struct fsl_espi_reg *reg_base = mspi->reg_base;
569 irqreturn_t ret = IRQ_NONE;
570 u32 events;
571
572 /* Get interrupt events(tx/rx) */
573 events = mpc8xxx_spi_read_reg(&reg_base->event);
574 if (events)
575 ret = IRQ_HANDLED;
576
577 dev_vdbg(mspi->dev, "%s: events %x\n", __func__, events);
578
579 fsl_espi_cpu_irq(mspi, events);
580
581 return ret;
582 }
583
584 static void fsl_espi_remove(struct mpc8xxx_spi *mspi)
585 {
586 iounmap(mspi->reg_base);
587 }
588
589 static struct spi_master * __devinit fsl_espi_probe(struct device *dev,
590 struct resource *mem, unsigned int irq)
591 {
592 struct fsl_spi_platform_data *pdata = dev->platform_data;
593 struct spi_master *master;
594 struct mpc8xxx_spi *mpc8xxx_spi;
595 struct fsl_espi_reg *reg_base;
596 u32 regval;
597 int i, ret = 0;
598
599 master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
600 if (!master) {
601 ret = -ENOMEM;
602 goto err;
603 }
604
605 dev_set_drvdata(dev, master);
606
607 ret = mpc8xxx_spi_probe(dev, mem, irq);
608 if (ret)
609 goto err_probe;
610
611 master->setup = fsl_espi_setup;
612
613 mpc8xxx_spi = spi_master_get_devdata(master);
614 mpc8xxx_spi->spi_do_one_msg = fsl_espi_do_one_msg;
615 mpc8xxx_spi->spi_remove = fsl_espi_remove;
616
617 mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem));
618 if (!mpc8xxx_spi->reg_base) {
619 ret = -ENOMEM;
620 goto err_probe;
621 }
622
623 reg_base = mpc8xxx_spi->reg_base;
624
625 /* Register for SPI Interrupt */
626 ret = request_irq(mpc8xxx_spi->irq, fsl_espi_irq,
627 0, "fsl_espi", mpc8xxx_spi);
628 if (ret)
629 goto free_irq;
630
631 if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
632 mpc8xxx_spi->rx_shift = 16;
633 mpc8xxx_spi->tx_shift = 24;
634 }
635
636 /* SPI controller initializations */
637 mpc8xxx_spi_write_reg(&reg_base->mode, 0);
638 mpc8xxx_spi_write_reg(&reg_base->mask, 0);
639 mpc8xxx_spi_write_reg(&reg_base->command, 0);
640 mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
641
642 /* Init eSPI CS mode register */
643 for (i = 0; i < pdata->max_chipselect; i++)
644 mpc8xxx_spi_write_reg(&reg_base->csmode[i], CSMODE_INIT_VAL);
645
646 /* Enable SPI interface */
647 regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
648
649 mpc8xxx_spi_write_reg(&reg_base->mode, regval);
650
651 ret = spi_register_master(master);
652 if (ret < 0)
653 goto unreg_master;
654
655 dev_info(dev, "at 0x%p (irq = %d)\n", reg_base, mpc8xxx_spi->irq);
656
657 return master;
658
659 unreg_master:
660 free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
661 free_irq:
662 iounmap(mpc8xxx_spi->reg_base);
663 err_probe:
664 spi_master_put(master);
665 err:
666 return ERR_PTR(ret);
667 }
668
669 static int of_fsl_espi_get_chipselects(struct device *dev)
670 {
671 struct device_node *np = dev->of_node;
672 struct fsl_spi_platform_data *pdata = dev->platform_data;
673 const u32 *prop;
674 int len;
675
676 prop = of_get_property(np, "fsl,espi-num-chipselects", &len);
677 if (!prop || len < sizeof(*prop)) {
678 dev_err(dev, "No 'fsl,espi-num-chipselects' property\n");
679 return -EINVAL;
680 }
681
682 pdata->max_chipselect = *prop;
683 pdata->cs_control = NULL;
684
685 return 0;
686 }
687
688 static int __devinit of_fsl_espi_probe(struct platform_device *ofdev)
689 {
690 struct device *dev = &ofdev->dev;
691 struct device_node *np = ofdev->dev.of_node;
692 struct spi_master *master;
693 struct resource mem;
694 struct resource irq;
695 int ret = -ENOMEM;
696
697 ret = of_mpc8xxx_spi_probe(ofdev);
698 if (ret)
699 return ret;
700
701 ret = of_fsl_espi_get_chipselects(dev);
702 if (ret)
703 goto err;
704
705 ret = of_address_to_resource(np, 0, &mem);
706 if (ret)
707 goto err;
708
709 ret = of_irq_to_resource(np, 0, &irq);
710 if (!ret) {
711 ret = -EINVAL;
712 goto err;
713 }
714
715 master = fsl_espi_probe(dev, &mem, irq.start);
716 if (IS_ERR(master)) {
717 ret = PTR_ERR(master);
718 goto err;
719 }
720
721 return 0;
722
723 err:
724 return ret;
725 }
726
727 static int __devexit of_fsl_espi_remove(struct platform_device *dev)
728 {
729 return mpc8xxx_spi_remove(&dev->dev);
730 }
731
732 static const struct of_device_id of_fsl_espi_match[] = {
733 { .compatible = "fsl,mpc8536-espi" },
734 {}
735 };
736 MODULE_DEVICE_TABLE(of, of_fsl_espi_match);
737
738 static struct platform_driver fsl_espi_driver = {
739 .driver = {
740 .name = "fsl_espi",
741 .owner = THIS_MODULE,
742 .of_match_table = of_fsl_espi_match,
743 },
744 .probe = of_fsl_espi_probe,
745 .remove = __devexit_p(of_fsl_espi_remove),
746 };
747
748 static int __init fsl_espi_init(void)
749 {
750 return platform_driver_register(&fsl_espi_driver);
751 }
752 module_init(fsl_espi_init);
753
754 static void __exit fsl_espi_exit(void)
755 {
756 platform_driver_unregister(&fsl_espi_driver);
757 }
758 module_exit(fsl_espi_exit);
759
760 MODULE_AUTHOR("Mingkai Hu");
761 MODULE_DESCRIPTION("Enhanced Freescale SPI Driver");
762 MODULE_LICENSE("GPL");
Linus' kernel tree