Version:  2.0.40 2.2.26 2.4.37 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 4.0 4.1 4.2 4.3 4.4 4.5 4.6

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/delay.h>
 23 #include <linux/dma-mapping.h>
 24 #include <linux/fsl_devices.h>
 25 #include <linux/gpio.h>
 26 #include <linux/interrupt.h>
 27 #include <linux/irq.h>
 28 #include <linux/kernel.h>
 29 #include <linux/mm.h>
 30 #include <linux/module.h>
 31 #include <linux/mutex.h>
 32 #include <linux/of.h>
 33 #include <linux/of_address.h>
 34 #include <linux/of_irq.h>
 35 #include <linux/of_gpio.h>
 36 #include <linux/of_platform.h>
 37 #include <linux/platform_device.h>
 38 #include <linux/spi/spi.h>
 39 #include <linux/spi/spi_bitbang.h>
 40 #include <linux/types.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 const 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         if (!hz)
243                 hz = spi->max_speed_hz;
244 
245         if (!(mpc8xxx_spi->flags & SPI_CPM_MODE))
246                 bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi,
247                                                            mpc8xxx_spi,
248                                                            bits_per_word);
249         else if (mpc8xxx_spi->flags & SPI_QE)
250                 bits_per_word = mspi_apply_qe_mode_quirks(cs, spi,
251                                                           bits_per_word);
252 
253         if (bits_per_word < 0)
254                 return bits_per_word;
255 
256         if (bits_per_word == 32)
257                 bits_per_word = 0;
258         else
259                 bits_per_word = bits_per_word - 1;
260 
261         /* mask out bits we are going to set */
262         cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16
263                                   | SPMODE_PM(0xF));
264 
265         cs->hw_mode |= SPMODE_LEN(bits_per_word);
266 
267         if ((mpc8xxx_spi->spibrg / hz) > 64) {
268                 cs->hw_mode |= SPMODE_DIV16;
269                 pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
270 
271                 WARN_ONCE(pm > 16, "%s: Requested speed is too low: %d Hz. "
272                           "Will use %d Hz instead.\n", dev_name(&spi->dev),
273                           hz, mpc8xxx_spi->spibrg / 1024);
274                 if (pm > 16)
275                         pm = 16;
276         } else {
277                 pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
278         }
279         if (pm)
280                 pm--;
281 
282         cs->hw_mode |= SPMODE_PM(pm);
283 
284         fsl_spi_change_mode(spi);
285         return 0;
286 }
287 
288 static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi,
289                                 struct spi_transfer *t, unsigned int len)
290 {
291         u32 word;
292         struct fsl_spi_reg *reg_base = mspi->reg_base;
293 
294         mspi->count = len;
295 
296         /* enable rx ints */
297         mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
298 
299         /* transmit word */
300         word = mspi->get_tx(mspi);
301         mpc8xxx_spi_write_reg(&reg_base->transmit, word);
302 
303         return 0;
304 }
305 
306 static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t,
307                             bool is_dma_mapped)
308 {
309         struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
310         struct fsl_spi_reg *reg_base;
311         unsigned int len = t->len;
312         u8 bits_per_word;
313         int ret;
314 
315         reg_base = mpc8xxx_spi->reg_base;
316         bits_per_word = spi->bits_per_word;
317         if (t->bits_per_word)
318                 bits_per_word = t->bits_per_word;
319 
320         if (bits_per_word > 8) {
321                 /* invalid length? */
322                 if (len & 1)
323                         return -EINVAL;
324                 len /= 2;
325         }
326         if (bits_per_word > 16) {
327                 /* invalid length? */
328                 if (len & 1)
329                         return -EINVAL;
330                 len /= 2;
331         }
332 
333         mpc8xxx_spi->tx = t->tx_buf;
334         mpc8xxx_spi->rx = t->rx_buf;
335 
336         reinit_completion(&mpc8xxx_spi->done);
337 
338         if (mpc8xxx_spi->flags & SPI_CPM_MODE)
339                 ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped);
340         else
341                 ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len);
342         if (ret)
343                 return ret;
344 
345         wait_for_completion(&mpc8xxx_spi->done);
346 
347         /* disable rx ints */
348         mpc8xxx_spi_write_reg(&reg_base->mask, 0);
349 
350         if (mpc8xxx_spi->flags & SPI_CPM_MODE)
351                 fsl_spi_cpm_bufs_complete(mpc8xxx_spi);
352 
353         return mpc8xxx_spi->count;
354 }
355 
356 static int fsl_spi_do_one_msg(struct spi_master *master,
357                               struct spi_message *m)
358 {
359         struct spi_device *spi = m->spi;
360         struct spi_transfer *t, *first;
361         unsigned int cs_change;
362         const int nsecs = 50;
363         int status;
364 
365         /* Don't allow changes if CS is active */
366         first = list_first_entry(&m->transfers, struct spi_transfer,
367                         transfer_list);
368         list_for_each_entry(t, &m->transfers, transfer_list) {
369                 if ((first->bits_per_word != t->bits_per_word) ||
370                         (first->speed_hz != t->speed_hz)) {
371                         dev_err(&spi->dev,
372                                 "bits_per_word/speed_hz should be same for the same SPI transfer\n");
373                         return -EINVAL;
374                 }
375         }
376 
377         cs_change = 1;
378         status = -EINVAL;
379         list_for_each_entry(t, &m->transfers, transfer_list) {
380                 if (t->bits_per_word || t->speed_hz) {
381                         if (cs_change)
382                                 status = fsl_spi_setup_transfer(spi, t);
383                         if (status < 0)
384                                 break;
385                 }
386 
387                 if (cs_change) {
388                         fsl_spi_chipselect(spi, BITBANG_CS_ACTIVE);
389                         ndelay(nsecs);
390                 }
391                 cs_change = t->cs_change;
392                 if (t->len)
393                         status = fsl_spi_bufs(spi, t, m->is_dma_mapped);
394                 if (status) {
395                         status = -EMSGSIZE;
396                         break;
397                 }
398                 m->actual_length += t->len;
399 
400                 if (t->delay_usecs)
401                         udelay(t->delay_usecs);
402 
403                 if (cs_change) {
404                         ndelay(nsecs);
405                         fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
406                         ndelay(nsecs);
407                 }
408         }
409 
410         m->status = status;
411         spi_finalize_current_message(master);
412 
413         if (status || !cs_change) {
414                 ndelay(nsecs);
415                 fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
416         }
417 
418         fsl_spi_setup_transfer(spi, NULL);
419         return 0;
420 }
421 
422 static int fsl_spi_setup(struct spi_device *spi)
423 {
424         struct mpc8xxx_spi *mpc8xxx_spi;
425         struct fsl_spi_reg *reg_base;
426         int retval;
427         u32 hw_mode;
428         struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
429 
430         if (!spi->max_speed_hz)
431                 return -EINVAL;
432 
433         if (!cs) {
434                 cs = kzalloc(sizeof(*cs), GFP_KERNEL);
435                 if (!cs)
436                         return -ENOMEM;
437                 spi_set_ctldata(spi, cs);
438         }
439         mpc8xxx_spi = spi_master_get_devdata(spi->master);
440 
441         reg_base = mpc8xxx_spi->reg_base;
442 
443         hw_mode = cs->hw_mode; /* Save original settings */
444         cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
445         /* mask out bits we are going to set */
446         cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
447                          | SPMODE_REV | SPMODE_LOOP);
448 
449         if (spi->mode & SPI_CPHA)
450                 cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
451         if (spi->mode & SPI_CPOL)
452                 cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
453         if (!(spi->mode & SPI_LSB_FIRST))
454                 cs->hw_mode |= SPMODE_REV;
455         if (spi->mode & SPI_LOOP)
456                 cs->hw_mode |= SPMODE_LOOP;
457 
458         retval = fsl_spi_setup_transfer(spi, NULL);
459         if (retval < 0) {
460                 cs->hw_mode = hw_mode; /* Restore settings */
461                 return retval;
462         }
463 
464         if (mpc8xxx_spi->type == TYPE_GRLIB) {
465                 if (gpio_is_valid(spi->cs_gpio)) {
466                         int desel;
467 
468                         retval = gpio_request(spi->cs_gpio,
469                                               dev_name(&spi->dev));
470                         if (retval)
471                                 return retval;
472 
473                         desel = !(spi->mode & SPI_CS_HIGH);
474                         retval = gpio_direction_output(spi->cs_gpio, desel);
475                         if (retval) {
476                                 gpio_free(spi->cs_gpio);
477                                 return retval;
478                         }
479                 } else if (spi->cs_gpio != -ENOENT) {
480                         if (spi->cs_gpio < 0)
481                                 return spi->cs_gpio;
482                         return -EINVAL;
483                 }
484                 /* When spi->cs_gpio == -ENOENT, a hole in the phandle list
485                  * indicates to use native chipselect if present, or allow for
486                  * an always selected chip
487                  */
488         }
489 
490         /* Initialize chipselect - might be active for SPI_CS_HIGH mode */
491         fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
492 
493         return 0;
494 }
495 
496 static void fsl_spi_cleanup(struct spi_device *spi)
497 {
498         struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
499         struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
500 
501         if (mpc8xxx_spi->type == TYPE_GRLIB && gpio_is_valid(spi->cs_gpio))
502                 gpio_free(spi->cs_gpio);
503 
504         kfree(cs);
505         spi_set_ctldata(spi, NULL);
506 }
507 
508 static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
509 {
510         struct fsl_spi_reg *reg_base = mspi->reg_base;
511 
512         /* We need handle RX first */
513         if (events & SPIE_NE) {
514                 u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
515 
516                 if (mspi->rx)
517                         mspi->get_rx(rx_data, mspi);
518         }
519 
520         if ((events & SPIE_NF) == 0)
521                 /* spin until TX is done */
522                 while (((events =
523                         mpc8xxx_spi_read_reg(&reg_base->event)) &
524                                                 SPIE_NF) == 0)
525                         cpu_relax();
526 
527         /* Clear the events */
528         mpc8xxx_spi_write_reg(&reg_base->event, events);
529 
530         mspi->count -= 1;
531         if (mspi->count) {
532                 u32 word = mspi->get_tx(mspi);
533 
534                 mpc8xxx_spi_write_reg(&reg_base->transmit, word);
535         } else {
536                 complete(&mspi->done);
537         }
538 }
539 
540 static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
541 {
542         struct mpc8xxx_spi *mspi = context_data;
543         irqreturn_t ret = IRQ_NONE;
544         u32 events;
545         struct fsl_spi_reg *reg_base = mspi->reg_base;
546 
547         /* Get interrupt events(tx/rx) */
548         events = mpc8xxx_spi_read_reg(&reg_base->event);
549         if (events)
550                 ret = IRQ_HANDLED;
551 
552         dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
553 
554         if (mspi->flags & SPI_CPM_MODE)
555                 fsl_spi_cpm_irq(mspi, events);
556         else
557                 fsl_spi_cpu_irq(mspi, events);
558 
559         return ret;
560 }
561 
562 static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on)
563 {
564         struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
565         struct fsl_spi_reg *reg_base = mpc8xxx_spi->reg_base;
566         u32 slvsel;
567         u16 cs = spi->chip_select;
568 
569         if (gpio_is_valid(spi->cs_gpio)) {
570                 gpio_set_value(spi->cs_gpio, on);
571         } else if (cs < mpc8xxx_spi->native_chipselects) {
572                 slvsel = mpc8xxx_spi_read_reg(&reg_base->slvsel);
573                 slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs));
574                 mpc8xxx_spi_write_reg(&reg_base->slvsel, slvsel);
575         }
576 }
577 
578 static void fsl_spi_grlib_probe(struct device *dev)
579 {
580         struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
581         struct spi_master *master = dev_get_drvdata(dev);
582         struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
583         struct fsl_spi_reg *reg_base = mpc8xxx_spi->reg_base;
584         int mbits;
585         u32 capabilities;
586 
587         capabilities = mpc8xxx_spi_read_reg(&reg_base->cap);
588 
589         mpc8xxx_spi->set_shifts = fsl_spi_grlib_set_shifts;
590         mbits = SPCAP_MAXWLEN(capabilities);
591         if (mbits)
592                 mpc8xxx_spi->max_bits_per_word = mbits + 1;
593 
594         mpc8xxx_spi->native_chipselects = 0;
595         if (SPCAP_SSEN(capabilities)) {
596                 mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities);
597                 mpc8xxx_spi_write_reg(&reg_base->slvsel, 0xffffffff);
598         }
599         master->num_chipselect = mpc8xxx_spi->native_chipselects;
600         pdata->cs_control = fsl_spi_grlib_cs_control;
601 }
602 
603 static struct spi_master * fsl_spi_probe(struct device *dev,
604                 struct resource *mem, unsigned int irq)
605 {
606         struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
607         struct spi_master *master;
608         struct mpc8xxx_spi *mpc8xxx_spi;
609         struct fsl_spi_reg *reg_base;
610         u32 regval;
611         int ret = 0;
612 
613         master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
614         if (master == NULL) {
615                 ret = -ENOMEM;
616                 goto err;
617         }
618 
619         dev_set_drvdata(dev, master);
620 
621         mpc8xxx_spi_probe(dev, mem, irq);
622 
623         master->setup = fsl_spi_setup;
624         master->cleanup = fsl_spi_cleanup;
625         master->transfer_one_message = fsl_spi_do_one_msg;
626 
627         mpc8xxx_spi = spi_master_get_devdata(master);
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 = devm_ioremap_resource(dev, mem);
636         if (IS_ERR(mpc8xxx_spi->reg_base)) {
637                 ret = PTR_ERR(mpc8xxx_spi->reg_base);
638                 goto err_probe;
639         }
640 
641         if (mpc8xxx_spi->type == TYPE_GRLIB)
642                 fsl_spi_grlib_probe(dev);
643 
644         master->bits_per_word_mask =
645                 (SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32)) &
646                 SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word);
647 
648         if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
649                 mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts;
650 
651         if (mpc8xxx_spi->set_shifts)
652                 /* 8 bits per word and MSB first */
653                 mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift,
654                                         &mpc8xxx_spi->tx_shift, 8, 1);
655 
656         /* Register for SPI Interrupt */
657         ret = devm_request_irq(dev, mpc8xxx_spi->irq, fsl_spi_irq,
658                                0, "fsl_spi", mpc8xxx_spi);
659 
660         if (ret != 0)
661                 goto err_probe;
662 
663         reg_base = mpc8xxx_spi->reg_base;
664 
665         /* SPI controller initializations */
666         mpc8xxx_spi_write_reg(&reg_base->mode, 0);
667         mpc8xxx_spi_write_reg(&reg_base->mask, 0);
668         mpc8xxx_spi_write_reg(&reg_base->command, 0);
669         mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
670 
671         /* Enable SPI interface */
672         regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
673         if (mpc8xxx_spi->max_bits_per_word < 8) {
674                 regval &= ~SPMODE_LEN(0xF);
675                 regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1);
676         }
677         if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
678                 regval |= SPMODE_OP;
679 
680         mpc8xxx_spi_write_reg(&reg_base->mode, regval);
681 
682         ret = devm_spi_register_master(dev, master);
683         if (ret < 0)
684                 goto err_probe;
685 
686         dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
687                  mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
688 
689         return master;
690 
691 err_probe:
692         fsl_spi_cpm_free(mpc8xxx_spi);
693 err_cpm_init:
694         spi_master_put(master);
695 err:
696         return ERR_PTR(ret);
697 }
698 
699 static void fsl_spi_cs_control(struct spi_device *spi, bool on)
700 {
701         struct device *dev = spi->dev.parent->parent;
702         struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
703         struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
704         u16 cs = spi->chip_select;
705         int gpio = pinfo->gpios[cs];
706         bool alow = pinfo->alow_flags[cs];
707 
708         gpio_set_value(gpio, on ^ alow);
709 }
710 
711 static int of_fsl_spi_get_chipselects(struct device *dev)
712 {
713         struct device_node *np = dev->of_node;
714         struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
715         struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
716         int ngpios;
717         int i = 0;
718         int ret;
719 
720         ngpios = of_gpio_count(np);
721         if (ngpios <= 0) {
722                 /*
723                  * SPI w/o chip-select line. One SPI device is still permitted
724                  * though.
725                  */
726                 pdata->max_chipselect = 1;
727                 return 0;
728         }
729 
730         pinfo->gpios = kmalloc(ngpios * sizeof(*pinfo->gpios), GFP_KERNEL);
731         if (!pinfo->gpios)
732                 return -ENOMEM;
733         memset(pinfo->gpios, -1, ngpios * sizeof(*pinfo->gpios));
734 
735         pinfo->alow_flags = kzalloc(ngpios * sizeof(*pinfo->alow_flags),
736                                     GFP_KERNEL);
737         if (!pinfo->alow_flags) {
738                 ret = -ENOMEM;
739                 goto err_alloc_flags;
740         }
741 
742         for (; i < ngpios; i++) {
743                 int gpio;
744                 enum of_gpio_flags flags;
745 
746                 gpio = of_get_gpio_flags(np, i, &flags);
747                 if (!gpio_is_valid(gpio)) {
748                         dev_err(dev, "invalid gpio #%d: %d\n", i, gpio);
749                         ret = gpio;
750                         goto err_loop;
751                 }
752 
753                 ret = gpio_request(gpio, dev_name(dev));
754                 if (ret) {
755                         dev_err(dev, "can't request gpio #%d: %d\n", i, ret);
756                         goto err_loop;
757                 }
758 
759                 pinfo->gpios[i] = gpio;
760                 pinfo->alow_flags[i] = flags & OF_GPIO_ACTIVE_LOW;
761 
762                 ret = gpio_direction_output(pinfo->gpios[i],
763                                             pinfo->alow_flags[i]);
764                 if (ret) {
765                         dev_err(dev, "can't set output direction for gpio "
766                                 "#%d: %d\n", i, ret);
767                         goto err_loop;
768                 }
769         }
770 
771         pdata->max_chipselect = ngpios;
772         pdata->cs_control = fsl_spi_cs_control;
773 
774         return 0;
775 
776 err_loop:
777         while (i >= 0) {
778                 if (gpio_is_valid(pinfo->gpios[i]))
779                         gpio_free(pinfo->gpios[i]);
780                 i--;
781         }
782 
783         kfree(pinfo->alow_flags);
784         pinfo->alow_flags = NULL;
785 err_alloc_flags:
786         kfree(pinfo->gpios);
787         pinfo->gpios = NULL;
788         return ret;
789 }
790 
791 static int of_fsl_spi_free_chipselects(struct device *dev)
792 {
793         struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
794         struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
795         int i;
796 
797         if (!pinfo->gpios)
798                 return 0;
799 
800         for (i = 0; i < pdata->max_chipselect; i++) {
801                 if (gpio_is_valid(pinfo->gpios[i]))
802                         gpio_free(pinfo->gpios[i]);
803         }
804 
805         kfree(pinfo->gpios);
806         kfree(pinfo->alow_flags);
807         return 0;
808 }
809 
810 static int of_fsl_spi_probe(struct platform_device *ofdev)
811 {
812         struct device *dev = &ofdev->dev;
813         struct device_node *np = ofdev->dev.of_node;
814         struct spi_master *master;
815         struct resource mem;
816         int irq, type;
817         int ret = -ENOMEM;
818 
819         ret = of_mpc8xxx_spi_probe(ofdev);
820         if (ret)
821                 return ret;
822 
823         type = fsl_spi_get_type(&ofdev->dev);
824         if (type == TYPE_FSL) {
825                 ret = of_fsl_spi_get_chipselects(dev);
826                 if (ret)
827                         goto err;
828         }
829 
830         ret = of_address_to_resource(np, 0, &mem);
831         if (ret)
832                 goto err;
833 
834         irq = irq_of_parse_and_map(np, 0);
835         if (!irq) {
836                 ret = -EINVAL;
837                 goto err;
838         }
839 
840         master = fsl_spi_probe(dev, &mem, irq);
841         if (IS_ERR(master)) {
842                 ret = PTR_ERR(master);
843                 goto err;
844         }
845 
846         return 0;
847 
848 err:
849         if (type == TYPE_FSL)
850                 of_fsl_spi_free_chipselects(dev);
851         return ret;
852 }
853 
854 static int of_fsl_spi_remove(struct platform_device *ofdev)
855 {
856         struct spi_master *master = platform_get_drvdata(ofdev);
857         struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
858 
859         fsl_spi_cpm_free(mpc8xxx_spi);
860         if (mpc8xxx_spi->type == TYPE_FSL)
861                 of_fsl_spi_free_chipselects(&ofdev->dev);
862         return 0;
863 }
864 
865 static struct platform_driver of_fsl_spi_driver = {
866         .driver = {
867                 .name = "fsl_spi",
868                 .of_match_table = of_fsl_spi_match,
869         },
870         .probe          = of_fsl_spi_probe,
871         .remove         = of_fsl_spi_remove,
872 };
873 
874 #ifdef CONFIG_MPC832x_RDB
875 /*
876  * XXX XXX XXX
877  * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
878  * only. The driver should go away soon, since newer MPC8323E-RDB's device
879  * tree can work with OpenFirmware driver. But for now we support old trees
880  * as well.
881  */
882 static int plat_mpc8xxx_spi_probe(struct platform_device *pdev)
883 {
884         struct resource *mem;
885         int irq;
886         struct spi_master *master;
887 
888         if (!dev_get_platdata(&pdev->dev))
889                 return -EINVAL;
890 
891         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
892         if (!mem)
893                 return -EINVAL;
894 
895         irq = platform_get_irq(pdev, 0);
896         if (irq <= 0)
897                 return -EINVAL;
898 
899         master = fsl_spi_probe(&pdev->dev, mem, irq);
900         return PTR_ERR_OR_ZERO(master);
901 }
902 
903 static int plat_mpc8xxx_spi_remove(struct platform_device *pdev)
904 {
905         struct spi_master *master = platform_get_drvdata(pdev);
906         struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
907 
908         fsl_spi_cpm_free(mpc8xxx_spi);
909 
910         return 0;
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         },
920 };
921 
922 static bool legacy_driver_failed;
923 
924 static void __init legacy_driver_register(void)
925 {
926         legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
927 }
928 
929 static void __exit legacy_driver_unregister(void)
930 {
931         if (legacy_driver_failed)
932                 return;
933         platform_driver_unregister(&mpc8xxx_spi_driver);
934 }
935 #else
936 static void __init legacy_driver_register(void) {}
937 static void __exit legacy_driver_unregister(void) {}
938 #endif /* CONFIG_MPC832x_RDB */
939 
940 static int __init fsl_spi_init(void)
941 {
942         legacy_driver_register();
943         return platform_driver_register(&of_fsl_spi_driver);
944 }
945 module_init(fsl_spi_init);
946 
947 static void __exit fsl_spi_exit(void)
948 {
949         platform_driver_unregister(&of_fsl_spi_driver);
950         legacy_driver_unregister();
951 }
952 module_exit(fsl_spi_exit);
953 
954 MODULE_AUTHOR("Kumar Gala");
955 MODULE_DESCRIPTION("Simple Freescale SPI Driver");
956 MODULE_LICENSE("GPL");
957 

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