]> Pileus Git - ~andy/linux/blob - drivers/spi/spi-fsl-spi.c
Linux 3.14
[~andy/linux] / drivers / spi / spi-fsl-spi.c
1 /*
2  * Freescale SPI controller driver.
3  *
4  * Maintainer: Kumar Gala
5  *
6  * Copyright (C) 2006 Polycom, Inc.
7  * Copyright 2010 Freescale Semiconductor, Inc.
8  *
9  * CPM SPI and QE buffer descriptors mode support:
10  * Copyright (c) 2009  MontaVista Software, Inc.
11  * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
12  *
13  * GRLIB support:
14  * Copyright (c) 2012 Aeroflex Gaisler AB.
15  * Author: Andreas Larsson <andreas@gaisler.com>
16  *
17  * This program is free software; you can redistribute  it and/or modify it
18  * under  the terms of  the GNU General  Public License as published by the
19  * Free Software Foundation;  either version 2 of the  License, or (at your
20  * option) any later version.
21  */
22 #include <linux/module.h>
23 #include <linux/types.h>
24 #include <linux/kernel.h>
25 #include <linux/interrupt.h>
26 #include <linux/delay.h>
27 #include <linux/irq.h>
28 #include <linux/spi/spi.h>
29 #include <linux/spi/spi_bitbang.h>
30 #include <linux/platform_device.h>
31 #include <linux/fsl_devices.h>
32 #include <linux/dma-mapping.h>
33 #include <linux/mm.h>
34 #include <linux/mutex.h>
35 #include <linux/of.h>
36 #include <linux/of_platform.h>
37 #include <linux/of_address.h>
38 #include <linux/of_irq.h>
39 #include <linux/gpio.h>
40 #include <linux/of_gpio.h>
41
42 #include "spi-fsl-lib.h"
43 #include "spi-fsl-cpm.h"
44 #include "spi-fsl-spi.h"
45
46 #define TYPE_FSL        0
47 #define TYPE_GRLIB      1
48
49 struct fsl_spi_match_data {
50         int type;
51 };
52
53 static struct fsl_spi_match_data of_fsl_spi_fsl_config = {
54         .type = TYPE_FSL,
55 };
56
57 static struct fsl_spi_match_data of_fsl_spi_grlib_config = {
58         .type = TYPE_GRLIB,
59 };
60
61 static struct of_device_id of_fsl_spi_match[] = {
62         {
63                 .compatible = "fsl,spi",
64                 .data = &of_fsl_spi_fsl_config,
65         },
66         {
67                 .compatible = "aeroflexgaisler,spictrl",
68                 .data = &of_fsl_spi_grlib_config,
69         },
70         {}
71 };
72 MODULE_DEVICE_TABLE(of, of_fsl_spi_match);
73
74 static int fsl_spi_get_type(struct device *dev)
75 {
76         const struct of_device_id *match;
77
78         if (dev->of_node) {
79                 match = of_match_node(of_fsl_spi_match, dev->of_node);
80                 if (match && match->data)
81                         return ((struct fsl_spi_match_data *)match->data)->type;
82         }
83         return TYPE_FSL;
84 }
85
86 static void fsl_spi_change_mode(struct spi_device *spi)
87 {
88         struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
89         struct spi_mpc8xxx_cs *cs = spi->controller_state;
90         struct fsl_spi_reg *reg_base = mspi->reg_base;
91         __be32 __iomem *mode = &reg_base->mode;
92         unsigned long flags;
93
94         if (cs->hw_mode == mpc8xxx_spi_read_reg(mode))
95                 return;
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         mpc8xxx_spi_write_reg(mode, cs->hw_mode & ~SPMODE_ENABLE);
102
103         /* When in CPM mode, we need to reinit tx and rx. */
104         if (mspi->flags & SPI_CPM_MODE) {
105                 fsl_spi_cpm_reinit_txrx(mspi);
106         }
107         mpc8xxx_spi_write_reg(mode, cs->hw_mode);
108         local_irq_restore(flags);
109 }
110
111 static void fsl_spi_chipselect(struct spi_device *spi, int value)
112 {
113         struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
114         struct fsl_spi_platform_data *pdata;
115         bool pol = spi->mode & SPI_CS_HIGH;
116         struct spi_mpc8xxx_cs   *cs = spi->controller_state;
117
118         pdata = spi->dev.parent->parent->platform_data;
119
120         if (value == BITBANG_CS_INACTIVE) {
121                 if (pdata->cs_control)
122                         pdata->cs_control(spi, !pol);
123         }
124
125         if (value == BITBANG_CS_ACTIVE) {
126                 mpc8xxx_spi->rx_shift = cs->rx_shift;
127                 mpc8xxx_spi->tx_shift = cs->tx_shift;
128                 mpc8xxx_spi->get_rx = cs->get_rx;
129                 mpc8xxx_spi->get_tx = cs->get_tx;
130
131                 fsl_spi_change_mode(spi);
132
133                 if (pdata->cs_control)
134                         pdata->cs_control(spi, pol);
135         }
136 }
137
138 static void fsl_spi_qe_cpu_set_shifts(u32 *rx_shift, u32 *tx_shift,
139                                       int bits_per_word, int msb_first)
140 {
141         *rx_shift = 0;
142         *tx_shift = 0;
143         if (msb_first) {
144                 if (bits_per_word <= 8) {
145                         *rx_shift = 16;
146                         *tx_shift = 24;
147                 } else if (bits_per_word <= 16) {
148                         *rx_shift = 16;
149                         *tx_shift = 16;
150                 }
151         } else {
152                 if (bits_per_word <= 8)
153                         *rx_shift = 8;
154         }
155 }
156
157 static void fsl_spi_grlib_set_shifts(u32 *rx_shift, u32 *tx_shift,
158                                      int bits_per_word, int msb_first)
159 {
160         *rx_shift = 0;
161         *tx_shift = 0;
162         if (bits_per_word <= 16) {
163                 if (msb_first) {
164                         *rx_shift = 16; /* LSB in bit 16 */
165                         *tx_shift = 32 - bits_per_word; /* MSB in bit 31 */
166                 } else {
167                         *rx_shift = 16 - bits_per_word; /* MSB in bit 15 */
168                 }
169         }
170 }
171
172 static int mspi_apply_cpu_mode_quirks(struct spi_mpc8xxx_cs *cs,
173                                 struct spi_device *spi,
174                                 struct mpc8xxx_spi *mpc8xxx_spi,
175                                 int bits_per_word)
176 {
177         cs->rx_shift = 0;
178         cs->tx_shift = 0;
179         if (bits_per_word <= 8) {
180                 cs->get_rx = mpc8xxx_spi_rx_buf_u8;
181                 cs->get_tx = mpc8xxx_spi_tx_buf_u8;
182         } else if (bits_per_word <= 16) {
183                 cs->get_rx = mpc8xxx_spi_rx_buf_u16;
184                 cs->get_tx = mpc8xxx_spi_tx_buf_u16;
185         } else if (bits_per_word <= 32) {
186                 cs->get_rx = mpc8xxx_spi_rx_buf_u32;
187                 cs->get_tx = mpc8xxx_spi_tx_buf_u32;
188         } else
189                 return -EINVAL;
190
191         if (mpc8xxx_spi->set_shifts)
192                 mpc8xxx_spi->set_shifts(&cs->rx_shift, &cs->tx_shift,
193                                         bits_per_word,
194                                         !(spi->mode & SPI_LSB_FIRST));
195
196         mpc8xxx_spi->rx_shift = cs->rx_shift;
197         mpc8xxx_spi->tx_shift = cs->tx_shift;
198         mpc8xxx_spi->get_rx = cs->get_rx;
199         mpc8xxx_spi->get_tx = cs->get_tx;
200
201         return bits_per_word;
202 }
203
204 static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs,
205                                 struct spi_device *spi,
206                                 int bits_per_word)
207 {
208         /* QE uses Little Endian for words > 8
209          * so transform all words > 8 into 8 bits
210          * Unfortnatly that doesn't work for LSB so
211          * reject these for now */
212         /* Note: 32 bits word, LSB works iff
213          * tfcr/rfcr is set to CPMFCR_GBL */
214         if (spi->mode & SPI_LSB_FIRST &&
215             bits_per_word > 8)
216                 return -EINVAL;
217         if (bits_per_word > 8)
218                 return 8; /* pretend its 8 bits */
219         return bits_per_word;
220 }
221
222 static int fsl_spi_setup_transfer(struct spi_device *spi,
223                                         struct spi_transfer *t)
224 {
225         struct mpc8xxx_spi *mpc8xxx_spi;
226         int bits_per_word = 0;
227         u8 pm;
228         u32 hz = 0;
229         struct spi_mpc8xxx_cs   *cs = spi->controller_state;
230
231         mpc8xxx_spi = spi_master_get_devdata(spi->master);
232
233         if (t) {
234                 bits_per_word = t->bits_per_word;
235                 hz = t->speed_hz;
236         }
237
238         /* spi_transfer level calls that work per-word */
239         if (!bits_per_word)
240                 bits_per_word = spi->bits_per_word;
241
242         /* Make sure its a bit width we support [4..16, 32] */
243         if ((bits_per_word < 4)
244             || ((bits_per_word > 16) && (bits_per_word != 32))
245             || (bits_per_word > mpc8xxx_spi->max_bits_per_word))
246                 return -EINVAL;
247
248         if (!hz)
249                 hz = spi->max_speed_hz;
250
251         if (!(mpc8xxx_spi->flags & SPI_CPM_MODE))
252                 bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi,
253                                                            mpc8xxx_spi,
254                                                            bits_per_word);
255         else if (mpc8xxx_spi->flags & SPI_QE)
256                 bits_per_word = mspi_apply_qe_mode_quirks(cs, spi,
257                                                           bits_per_word);
258
259         if (bits_per_word < 0)
260                 return bits_per_word;
261
262         if (bits_per_word == 32)
263                 bits_per_word = 0;
264         else
265                 bits_per_word = bits_per_word - 1;
266
267         /* mask out bits we are going to set */
268         cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16
269                                   | SPMODE_PM(0xF));
270
271         cs->hw_mode |= SPMODE_LEN(bits_per_word);
272
273         if ((mpc8xxx_spi->spibrg / hz) > 64) {
274                 cs->hw_mode |= SPMODE_DIV16;
275                 pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
276
277                 WARN_ONCE(pm > 16, "%s: Requested speed is too low: %d Hz. "
278                           "Will use %d Hz instead.\n", dev_name(&spi->dev),
279                           hz, mpc8xxx_spi->spibrg / 1024);
280                 if (pm > 16)
281                         pm = 16;
282         } else {
283                 pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
284         }
285         if (pm)
286                 pm--;
287
288         cs->hw_mode |= SPMODE_PM(pm);
289
290         fsl_spi_change_mode(spi);
291         return 0;
292 }
293
294 static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi,
295                                 struct spi_transfer *t, unsigned int len)
296 {
297         u32 word;
298         struct fsl_spi_reg *reg_base = mspi->reg_base;
299
300         mspi->count = len;
301
302         /* enable rx ints */
303         mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
304
305         /* transmit word */
306         word = mspi->get_tx(mspi);
307         mpc8xxx_spi_write_reg(&reg_base->transmit, word);
308
309         return 0;
310 }
311
312 static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t,
313                             bool is_dma_mapped)
314 {
315         struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
316         struct fsl_spi_reg *reg_base;
317         unsigned int len = t->len;
318         u8 bits_per_word;
319         int ret;
320
321         reg_base = mpc8xxx_spi->reg_base;
322         bits_per_word = spi->bits_per_word;
323         if (t->bits_per_word)
324                 bits_per_word = t->bits_per_word;
325
326         if (bits_per_word > 8) {
327                 /* invalid length? */
328                 if (len & 1)
329                         return -EINVAL;
330                 len /= 2;
331         }
332         if (bits_per_word > 16) {
333                 /* invalid length? */
334                 if (len & 1)
335                         return -EINVAL;
336                 len /= 2;
337         }
338
339         mpc8xxx_spi->tx = t->tx_buf;
340         mpc8xxx_spi->rx = t->rx_buf;
341
342         reinit_completion(&mpc8xxx_spi->done);
343
344         if (mpc8xxx_spi->flags & SPI_CPM_MODE)
345                 ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped);
346         else
347                 ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len);
348         if (ret)
349                 return ret;
350
351         wait_for_completion(&mpc8xxx_spi->done);
352
353         /* disable rx ints */
354         mpc8xxx_spi_write_reg(&reg_base->mask, 0);
355
356         if (mpc8xxx_spi->flags & SPI_CPM_MODE)
357                 fsl_spi_cpm_bufs_complete(mpc8xxx_spi);
358
359         return mpc8xxx_spi->count;
360 }
361
362 static void fsl_spi_do_one_msg(struct spi_message *m)
363 {
364         struct spi_device *spi = m->spi;
365         struct spi_transfer *t;
366         unsigned int cs_change;
367         const int nsecs = 50;
368         int status;
369
370         cs_change = 1;
371         status = 0;
372         list_for_each_entry(t, &m->transfers, transfer_list) {
373                 if (t->bits_per_word || t->speed_hz) {
374                         /* Don't allow changes if CS is active */
375                         status = -EINVAL;
376
377                         if (cs_change)
378                                 status = fsl_spi_setup_transfer(spi, t);
379                         if (status < 0)
380                                 break;
381                 }
382
383                 if (cs_change) {
384                         fsl_spi_chipselect(spi, BITBANG_CS_ACTIVE);
385                         ndelay(nsecs);
386                 }
387                 cs_change = t->cs_change;
388                 if (t->len)
389                         status = fsl_spi_bufs(spi, t, m->is_dma_mapped);
390                 if (status) {
391                         status = -EMSGSIZE;
392                         break;
393                 }
394                 m->actual_length += t->len;
395
396                 if (t->delay_usecs)
397                         udelay(t->delay_usecs);
398
399                 if (cs_change) {
400                         ndelay(nsecs);
401                         fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
402                         ndelay(nsecs);
403                 }
404         }
405
406         m->status = status;
407         m->complete(m->context);
408
409         if (status || !cs_change) {
410                 ndelay(nsecs);
411                 fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
412         }
413
414         fsl_spi_setup_transfer(spi, NULL);
415 }
416
417 static int fsl_spi_setup(struct spi_device *spi)
418 {
419         struct mpc8xxx_spi *mpc8xxx_spi;
420         struct fsl_spi_reg *reg_base;
421         int retval;
422         u32 hw_mode;
423         struct spi_mpc8xxx_cs   *cs = spi->controller_state;
424
425         if (!spi->max_speed_hz)
426                 return -EINVAL;
427
428         if (!cs) {
429                 cs = kzalloc(sizeof *cs, GFP_KERNEL);
430                 if (!cs)
431                         return -ENOMEM;
432                 spi->controller_state = cs;
433         }
434         mpc8xxx_spi = spi_master_get_devdata(spi->master);
435
436         reg_base = mpc8xxx_spi->reg_base;
437
438         hw_mode = cs->hw_mode; /* Save original settings */
439         cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
440         /* mask out bits we are going to set */
441         cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
442                          | SPMODE_REV | SPMODE_LOOP);
443
444         if (spi->mode & SPI_CPHA)
445                 cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
446         if (spi->mode & SPI_CPOL)
447                 cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
448         if (!(spi->mode & SPI_LSB_FIRST))
449                 cs->hw_mode |= SPMODE_REV;
450         if (spi->mode & SPI_LOOP)
451                 cs->hw_mode |= SPMODE_LOOP;
452
453         retval = fsl_spi_setup_transfer(spi, NULL);
454         if (retval < 0) {
455                 cs->hw_mode = hw_mode; /* Restore settings */
456                 return retval;
457         }
458
459         if (mpc8xxx_spi->type == TYPE_GRLIB) {
460                 if (gpio_is_valid(spi->cs_gpio)) {
461                         int desel;
462
463                         retval = gpio_request(spi->cs_gpio,
464                                               dev_name(&spi->dev));
465                         if (retval)
466                                 return retval;
467
468                         desel = !(spi->mode & SPI_CS_HIGH);
469                         retval = gpio_direction_output(spi->cs_gpio, desel);
470                         if (retval) {
471                                 gpio_free(spi->cs_gpio);
472                                 return retval;
473                         }
474                 } else if (spi->cs_gpio != -ENOENT) {
475                         if (spi->cs_gpio < 0)
476                                 return spi->cs_gpio;
477                         return -EINVAL;
478                 }
479                 /* When spi->cs_gpio == -ENOENT, a hole in the phandle list
480                  * indicates to use native chipselect if present, or allow for
481                  * an always selected chip
482                  */
483         }
484
485         /* Initialize chipselect - might be active for SPI_CS_HIGH mode */
486         fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
487
488         return 0;
489 }
490
491 static void fsl_spi_cleanup(struct spi_device *spi)
492 {
493         struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
494
495         if (mpc8xxx_spi->type == TYPE_GRLIB && gpio_is_valid(spi->cs_gpio))
496                 gpio_free(spi->cs_gpio);
497 }
498
499 static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
500 {
501         struct fsl_spi_reg *reg_base = mspi->reg_base;
502
503         /* We need handle RX first */
504         if (events & SPIE_NE) {
505                 u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
506
507                 if (mspi->rx)
508                         mspi->get_rx(rx_data, mspi);
509         }
510
511         if ((events & SPIE_NF) == 0)
512                 /* spin until TX is done */
513                 while (((events =
514                         mpc8xxx_spi_read_reg(&reg_base->event)) &
515                                                 SPIE_NF) == 0)
516                         cpu_relax();
517
518         /* Clear the events */
519         mpc8xxx_spi_write_reg(&reg_base->event, events);
520
521         mspi->count -= 1;
522         if (mspi->count) {
523                 u32 word = mspi->get_tx(mspi);
524
525                 mpc8xxx_spi_write_reg(&reg_base->transmit, word);
526         } else {
527                 complete(&mspi->done);
528         }
529 }
530
531 static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
532 {
533         struct mpc8xxx_spi *mspi = context_data;
534         irqreturn_t ret = IRQ_NONE;
535         u32 events;
536         struct fsl_spi_reg *reg_base = mspi->reg_base;
537
538         /* Get interrupt events(tx/rx) */
539         events = mpc8xxx_spi_read_reg(&reg_base->event);
540         if (events)
541                 ret = IRQ_HANDLED;
542
543         dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
544
545         if (mspi->flags & SPI_CPM_MODE)
546                 fsl_spi_cpm_irq(mspi, events);
547         else
548                 fsl_spi_cpu_irq(mspi, events);
549
550         return ret;
551 }
552
553 static void fsl_spi_remove(struct mpc8xxx_spi *mspi)
554 {
555         iounmap(mspi->reg_base);
556         fsl_spi_cpm_free(mspi);
557 }
558
559 static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on)
560 {
561         struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
562         struct fsl_spi_reg *reg_base = mpc8xxx_spi->reg_base;
563         u32 slvsel;
564         u16 cs = spi->chip_select;
565
566         if (gpio_is_valid(spi->cs_gpio)) {
567                 gpio_set_value(spi->cs_gpio, on);
568         } else if (cs < mpc8xxx_spi->native_chipselects) {
569                 slvsel = mpc8xxx_spi_read_reg(&reg_base->slvsel);
570                 slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs));
571                 mpc8xxx_spi_write_reg(&reg_base->slvsel, slvsel);
572         }
573 }
574
575 static void fsl_spi_grlib_probe(struct device *dev)
576 {
577         struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
578         struct spi_master *master = dev_get_drvdata(dev);
579         struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
580         struct fsl_spi_reg *reg_base = mpc8xxx_spi->reg_base;
581         int mbits;
582         u32 capabilities;
583
584         capabilities = mpc8xxx_spi_read_reg(&reg_base->cap);
585
586         mpc8xxx_spi->set_shifts = fsl_spi_grlib_set_shifts;
587         mbits = SPCAP_MAXWLEN(capabilities);
588         if (mbits)
589                 mpc8xxx_spi->max_bits_per_word = mbits + 1;
590
591         mpc8xxx_spi->native_chipselects = 0;
592         if (SPCAP_SSEN(capabilities)) {
593                 mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities);
594                 mpc8xxx_spi_write_reg(&reg_base->slvsel, 0xffffffff);
595         }
596         master->num_chipselect = mpc8xxx_spi->native_chipselects;
597         pdata->cs_control = fsl_spi_grlib_cs_control;
598 }
599
600 static struct spi_master * fsl_spi_probe(struct device *dev,
601                 struct resource *mem, unsigned int irq)
602 {
603         struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
604         struct spi_master *master;
605         struct mpc8xxx_spi *mpc8xxx_spi;
606         struct fsl_spi_reg *reg_base;
607         u32 regval;
608         int ret = 0;
609
610         master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
611         if (master == NULL) {
612                 ret = -ENOMEM;
613                 goto err;
614         }
615
616         dev_set_drvdata(dev, master);
617
618         ret = mpc8xxx_spi_probe(dev, mem, irq);
619         if (ret)
620                 goto err_probe;
621
622         master->setup = fsl_spi_setup;
623         master->cleanup = fsl_spi_cleanup;
624
625         mpc8xxx_spi = spi_master_get_devdata(master);
626         mpc8xxx_spi->spi_do_one_msg = fsl_spi_do_one_msg;
627         mpc8xxx_spi->spi_remove = fsl_spi_remove;
628         mpc8xxx_spi->max_bits_per_word = 32;
629         mpc8xxx_spi->type = fsl_spi_get_type(dev);
630
631         ret = fsl_spi_cpm_init(mpc8xxx_spi);
632         if (ret)
633                 goto err_cpm_init;
634
635         mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem));
636         if (mpc8xxx_spi->reg_base == NULL) {
637                 ret = -ENOMEM;
638                 goto err_ioremap;
639         }
640
641         if (mpc8xxx_spi->type == TYPE_GRLIB)
642                 fsl_spi_grlib_probe(dev);
643
644         if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
645                 mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts;
646
647         if (mpc8xxx_spi->set_shifts)
648                 /* 8 bits per word and MSB first */
649                 mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift,
650                                         &mpc8xxx_spi->tx_shift, 8, 1);
651
652         /* Register for SPI Interrupt */
653         ret = request_irq(mpc8xxx_spi->irq, fsl_spi_irq,
654                           0, "fsl_spi", mpc8xxx_spi);
655
656         if (ret != 0)
657                 goto free_irq;
658
659         reg_base = mpc8xxx_spi->reg_base;
660
661         /* SPI controller initializations */
662         mpc8xxx_spi_write_reg(&reg_base->mode, 0);
663         mpc8xxx_spi_write_reg(&reg_base->mask, 0);
664         mpc8xxx_spi_write_reg(&reg_base->command, 0);
665         mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
666
667         /* Enable SPI interface */
668         regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
669         if (mpc8xxx_spi->max_bits_per_word < 8) {
670                 regval &= ~SPMODE_LEN(0xF);
671                 regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1);
672         }
673         if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
674                 regval |= SPMODE_OP;
675
676         mpc8xxx_spi_write_reg(&reg_base->mode, regval);
677
678         ret = spi_register_master(master);
679         if (ret < 0)
680                 goto unreg_master;
681
682         dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
683                  mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
684
685         return master;
686
687 unreg_master:
688         free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
689 free_irq:
690         iounmap(mpc8xxx_spi->reg_base);
691 err_ioremap:
692         fsl_spi_cpm_free(mpc8xxx_spi);
693 err_cpm_init:
694 err_probe:
695         spi_master_put(master);
696 err:
697         return ERR_PTR(ret);
698 }
699
700 static void fsl_spi_cs_control(struct spi_device *spi, bool on)
701 {
702         struct device *dev = spi->dev.parent->parent;
703         struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
704         struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
705         u16 cs = spi->chip_select;
706         int gpio = pinfo->gpios[cs];
707         bool alow = pinfo->alow_flags[cs];
708
709         gpio_set_value(gpio, on ^ alow);
710 }
711
712 static int of_fsl_spi_get_chipselects(struct device *dev)
713 {
714         struct device_node *np = dev->of_node;
715         struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
716         struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
717         int ngpios;
718         int i = 0;
719         int ret;
720
721         ngpios = of_gpio_count(np);
722         if (ngpios <= 0) {
723                 /*
724                  * SPI w/o chip-select line. One SPI device is still permitted
725                  * though.
726                  */
727                 pdata->max_chipselect = 1;
728                 return 0;
729         }
730
731         pinfo->gpios = kmalloc(ngpios * sizeof(*pinfo->gpios), GFP_KERNEL);
732         if (!pinfo->gpios)
733                 return -ENOMEM;
734         memset(pinfo->gpios, -1, ngpios * sizeof(*pinfo->gpios));
735
736         pinfo->alow_flags = kzalloc(ngpios * sizeof(*pinfo->alow_flags),
737                                     GFP_KERNEL);
738         if (!pinfo->alow_flags) {
739                 ret = -ENOMEM;
740                 goto err_alloc_flags;
741         }
742
743         for (; i < ngpios; i++) {
744                 int gpio;
745                 enum of_gpio_flags flags;
746
747                 gpio = of_get_gpio_flags(np, i, &flags);
748                 if (!gpio_is_valid(gpio)) {
749                         dev_err(dev, "invalid gpio #%d: %d\n", i, gpio);
750                         ret = gpio;
751                         goto err_loop;
752                 }
753
754                 ret = gpio_request(gpio, dev_name(dev));
755                 if (ret) {
756                         dev_err(dev, "can't request gpio #%d: %d\n", i, ret);
757                         goto err_loop;
758                 }
759
760                 pinfo->gpios[i] = gpio;
761                 pinfo->alow_flags[i] = flags & OF_GPIO_ACTIVE_LOW;
762
763                 ret = gpio_direction_output(pinfo->gpios[i],
764                                             pinfo->alow_flags[i]);
765                 if (ret) {
766                         dev_err(dev, "can't set output direction for gpio "
767                                 "#%d: %d\n", i, ret);
768                         goto err_loop;
769                 }
770         }
771
772         pdata->max_chipselect = ngpios;
773         pdata->cs_control = fsl_spi_cs_control;
774
775         return 0;
776
777 err_loop:
778         while (i >= 0) {
779                 if (gpio_is_valid(pinfo->gpios[i]))
780                         gpio_free(pinfo->gpios[i]);
781                 i--;
782         }
783
784         kfree(pinfo->alow_flags);
785         pinfo->alow_flags = NULL;
786 err_alloc_flags:
787         kfree(pinfo->gpios);
788         pinfo->gpios = NULL;
789         return ret;
790 }
791
792 static int of_fsl_spi_free_chipselects(struct device *dev)
793 {
794         struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
795         struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
796         int i;
797
798         if (!pinfo->gpios)
799                 return 0;
800
801         for (i = 0; i < pdata->max_chipselect; i++) {
802                 if (gpio_is_valid(pinfo->gpios[i]))
803                         gpio_free(pinfo->gpios[i]);
804         }
805
806         kfree(pinfo->gpios);
807         kfree(pinfo->alow_flags);
808         return 0;
809 }
810
811 static int of_fsl_spi_probe(struct platform_device *ofdev)
812 {
813         struct device *dev = &ofdev->dev;
814         struct device_node *np = ofdev->dev.of_node;
815         struct spi_master *master;
816         struct resource mem;
817         int irq, type;
818         int ret = -ENOMEM;
819
820         ret = of_mpc8xxx_spi_probe(ofdev);
821         if (ret)
822                 return ret;
823
824         type = fsl_spi_get_type(&ofdev->dev);
825         if (type == TYPE_FSL) {
826                 ret = of_fsl_spi_get_chipselects(dev);
827                 if (ret)
828                         goto err;
829         }
830
831         ret = of_address_to_resource(np, 0, &mem);
832         if (ret)
833                 goto err;
834
835         irq = irq_of_parse_and_map(np, 0);
836         if (!irq) {
837                 ret = -EINVAL;
838                 goto err;
839         }
840
841         master = fsl_spi_probe(dev, &mem, irq);
842         if (IS_ERR(master)) {
843                 ret = PTR_ERR(master);
844                 goto err;
845         }
846
847         return 0;
848
849 err:
850         if (type == TYPE_FSL)
851                 of_fsl_spi_free_chipselects(dev);
852         return ret;
853 }
854
855 static int of_fsl_spi_remove(struct platform_device *ofdev)
856 {
857         struct spi_master *master = platform_get_drvdata(ofdev);
858         struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
859         int ret;
860
861         ret = mpc8xxx_spi_remove(&ofdev->dev);
862         if (ret)
863                 return ret;
864         if (mpc8xxx_spi->type == TYPE_FSL)
865                 of_fsl_spi_free_chipselects(&ofdev->dev);
866         return 0;
867 }
868
869 static struct platform_driver of_fsl_spi_driver = {
870         .driver = {
871                 .name = "fsl_spi",
872                 .owner = THIS_MODULE,
873                 .of_match_table = of_fsl_spi_match,
874         },
875         .probe          = of_fsl_spi_probe,
876         .remove         = of_fsl_spi_remove,
877 };
878
879 #ifdef CONFIG_MPC832x_RDB
880 /*
881  * XXX XXX XXX
882  * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
883  * only. The driver should go away soon, since newer MPC8323E-RDB's device
884  * tree can work with OpenFirmware driver. But for now we support old trees
885  * as well.
886  */
887 static int plat_mpc8xxx_spi_probe(struct platform_device *pdev)
888 {
889         struct resource *mem;
890         int irq;
891         struct spi_master *master;
892
893         if (!dev_get_platdata(&pdev->dev))
894                 return -EINVAL;
895
896         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
897         if (!mem)
898                 return -EINVAL;
899
900         irq = platform_get_irq(pdev, 0);
901         if (irq <= 0)
902                 return -EINVAL;
903
904         master = fsl_spi_probe(&pdev->dev, mem, irq);
905         return PTR_ERR_OR_ZERO(master);
906 }
907
908 static int plat_mpc8xxx_spi_remove(struct platform_device *pdev)
909 {
910         return mpc8xxx_spi_remove(&pdev->dev);
911 }
912
913 MODULE_ALIAS("platform:mpc8xxx_spi");
914 static struct platform_driver mpc8xxx_spi_driver = {
915         .probe = plat_mpc8xxx_spi_probe,
916         .remove = plat_mpc8xxx_spi_remove,
917         .driver = {
918                 .name = "mpc8xxx_spi",
919                 .owner = THIS_MODULE,
920         },
921 };
922
923 static bool legacy_driver_failed;
924
925 static void __init legacy_driver_register(void)
926 {
927         legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
928 }
929
930 static void __exit legacy_driver_unregister(void)
931 {
932         if (legacy_driver_failed)
933                 return;
934         platform_driver_unregister(&mpc8xxx_spi_driver);
935 }
936 #else
937 static void __init legacy_driver_register(void) {}
938 static void __exit legacy_driver_unregister(void) {}
939 #endif /* CONFIG_MPC832x_RDB */
940
941 static int __init fsl_spi_init(void)
942 {
943         legacy_driver_register();
944         return platform_driver_register(&of_fsl_spi_driver);
945 }
946 module_init(fsl_spi_init);
947
948 static void __exit fsl_spi_exit(void)
949 {
950         platform_driver_unregister(&of_fsl_spi_driver);
951         legacy_driver_unregister();
952 }
953 module_exit(fsl_spi_exit);
954
955 MODULE_AUTHOR("Kumar Gala");
956 MODULE_DESCRIPTION("Simple Freescale SPI Driver");
957 MODULE_LICENSE("GPL");