xref: /openbmc/linux/drivers/spi/spi-fsl-spi.c (revision 4a44a19b)
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 void fsl_spi_do_one_msg(struct spi_message *m)
357 {
358 	struct spi_device *spi = m->spi;
359 	struct spi_transfer *t, *first;
360 	unsigned int cs_change;
361 	const int nsecs = 50;
362 	int status;
363 
364 	/* Don't allow changes if CS is active */
365 	first = list_first_entry(&m->transfers, struct spi_transfer,
366 			transfer_list);
367 	list_for_each_entry(t, &m->transfers, transfer_list) {
368 		if ((first->bits_per_word != t->bits_per_word) ||
369 			(first->speed_hz != t->speed_hz)) {
370 			status = -EINVAL;
371 			dev_err(&spi->dev,
372 				"bits_per_word/speed_hz should be same for the same SPI transfer\n");
373 			return;
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 	if (m->complete)
412 		m->complete(m->context);
413 
414 	if (status || !cs_change) {
415 		ndelay(nsecs);
416 		fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
417 	}
418 
419 	fsl_spi_setup_transfer(spi, NULL);
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_remove(struct mpc8xxx_spi *mspi)
563 {
564 	iounmap(mspi->reg_base);
565 	fsl_spi_cpm_free(mspi);
566 }
567 
568 static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on)
569 {
570 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
571 	struct fsl_spi_reg *reg_base = mpc8xxx_spi->reg_base;
572 	u32 slvsel;
573 	u16 cs = spi->chip_select;
574 
575 	if (gpio_is_valid(spi->cs_gpio)) {
576 		gpio_set_value(spi->cs_gpio, on);
577 	} else if (cs < mpc8xxx_spi->native_chipselects) {
578 		slvsel = mpc8xxx_spi_read_reg(&reg_base->slvsel);
579 		slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs));
580 		mpc8xxx_spi_write_reg(&reg_base->slvsel, slvsel);
581 	}
582 }
583 
584 static void fsl_spi_grlib_probe(struct device *dev)
585 {
586 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
587 	struct spi_master *master = dev_get_drvdata(dev);
588 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
589 	struct fsl_spi_reg *reg_base = mpc8xxx_spi->reg_base;
590 	int mbits;
591 	u32 capabilities;
592 
593 	capabilities = mpc8xxx_spi_read_reg(&reg_base->cap);
594 
595 	mpc8xxx_spi->set_shifts = fsl_spi_grlib_set_shifts;
596 	mbits = SPCAP_MAXWLEN(capabilities);
597 	if (mbits)
598 		mpc8xxx_spi->max_bits_per_word = mbits + 1;
599 
600 	mpc8xxx_spi->native_chipselects = 0;
601 	if (SPCAP_SSEN(capabilities)) {
602 		mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities);
603 		mpc8xxx_spi_write_reg(&reg_base->slvsel, 0xffffffff);
604 	}
605 	master->num_chipselect = mpc8xxx_spi->native_chipselects;
606 	pdata->cs_control = fsl_spi_grlib_cs_control;
607 }
608 
609 static struct spi_master * fsl_spi_probe(struct device *dev,
610 		struct resource *mem, unsigned int irq)
611 {
612 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
613 	struct spi_master *master;
614 	struct mpc8xxx_spi *mpc8xxx_spi;
615 	struct fsl_spi_reg *reg_base;
616 	u32 regval;
617 	int ret = 0;
618 
619 	master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
620 	if (master == NULL) {
621 		ret = -ENOMEM;
622 		goto err;
623 	}
624 
625 	dev_set_drvdata(dev, master);
626 
627 	ret = mpc8xxx_spi_probe(dev, mem, irq);
628 	if (ret)
629 		goto err_probe;
630 
631 	master->setup = fsl_spi_setup;
632 	master->cleanup = fsl_spi_cleanup;
633 
634 	mpc8xxx_spi = spi_master_get_devdata(master);
635 	mpc8xxx_spi->spi_do_one_msg = fsl_spi_do_one_msg;
636 	mpc8xxx_spi->spi_remove = fsl_spi_remove;
637 	mpc8xxx_spi->max_bits_per_word = 32;
638 	mpc8xxx_spi->type = fsl_spi_get_type(dev);
639 
640 	ret = fsl_spi_cpm_init(mpc8xxx_spi);
641 	if (ret)
642 		goto err_cpm_init;
643 
644 	mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem));
645 	if (mpc8xxx_spi->reg_base == NULL) {
646 		ret = -ENOMEM;
647 		goto err_ioremap;
648 	}
649 
650 	if (mpc8xxx_spi->type == TYPE_GRLIB)
651 		fsl_spi_grlib_probe(dev);
652 
653 	master->bits_per_word_mask =
654 		(SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32)) &
655 		SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word);
656 
657 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
658 		mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts;
659 
660 	if (mpc8xxx_spi->set_shifts)
661 		/* 8 bits per word and MSB first */
662 		mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift,
663 					&mpc8xxx_spi->tx_shift, 8, 1);
664 
665 	/* Register for SPI Interrupt */
666 	ret = request_irq(mpc8xxx_spi->irq, fsl_spi_irq,
667 			  0, "fsl_spi", mpc8xxx_spi);
668 
669 	if (ret != 0)
670 		goto free_irq;
671 
672 	reg_base = mpc8xxx_spi->reg_base;
673 
674 	/* SPI controller initializations */
675 	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
676 	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
677 	mpc8xxx_spi_write_reg(&reg_base->command, 0);
678 	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
679 
680 	/* Enable SPI interface */
681 	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
682 	if (mpc8xxx_spi->max_bits_per_word < 8) {
683 		regval &= ~SPMODE_LEN(0xF);
684 		regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1);
685 	}
686 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
687 		regval |= SPMODE_OP;
688 
689 	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
690 
691 	ret = spi_register_master(master);
692 	if (ret < 0)
693 		goto unreg_master;
694 
695 	dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
696 		 mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
697 
698 	return master;
699 
700 unreg_master:
701 	free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
702 free_irq:
703 	iounmap(mpc8xxx_spi->reg_base);
704 err_ioremap:
705 	fsl_spi_cpm_free(mpc8xxx_spi);
706 err_cpm_init:
707 err_probe:
708 	spi_master_put(master);
709 err:
710 	return ERR_PTR(ret);
711 }
712 
713 static void fsl_spi_cs_control(struct spi_device *spi, bool on)
714 {
715 	struct device *dev = spi->dev.parent->parent;
716 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
717 	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
718 	u16 cs = spi->chip_select;
719 	int gpio = pinfo->gpios[cs];
720 	bool alow = pinfo->alow_flags[cs];
721 
722 	gpio_set_value(gpio, on ^ alow);
723 }
724 
725 static int of_fsl_spi_get_chipselects(struct device *dev)
726 {
727 	struct device_node *np = dev->of_node;
728 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
729 	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
730 	int ngpios;
731 	int i = 0;
732 	int ret;
733 
734 	ngpios = of_gpio_count(np);
735 	if (ngpios <= 0) {
736 		/*
737 		 * SPI w/o chip-select line. One SPI device is still permitted
738 		 * though.
739 		 */
740 		pdata->max_chipselect = 1;
741 		return 0;
742 	}
743 
744 	pinfo->gpios = kmalloc(ngpios * sizeof(*pinfo->gpios), GFP_KERNEL);
745 	if (!pinfo->gpios)
746 		return -ENOMEM;
747 	memset(pinfo->gpios, -1, ngpios * sizeof(*pinfo->gpios));
748 
749 	pinfo->alow_flags = kzalloc(ngpios * sizeof(*pinfo->alow_flags),
750 				    GFP_KERNEL);
751 	if (!pinfo->alow_flags) {
752 		ret = -ENOMEM;
753 		goto err_alloc_flags;
754 	}
755 
756 	for (; i < ngpios; i++) {
757 		int gpio;
758 		enum of_gpio_flags flags;
759 
760 		gpio = of_get_gpio_flags(np, i, &flags);
761 		if (!gpio_is_valid(gpio)) {
762 			dev_err(dev, "invalid gpio #%d: %d\n", i, gpio);
763 			ret = gpio;
764 			goto err_loop;
765 		}
766 
767 		ret = gpio_request(gpio, dev_name(dev));
768 		if (ret) {
769 			dev_err(dev, "can't request gpio #%d: %d\n", i, ret);
770 			goto err_loop;
771 		}
772 
773 		pinfo->gpios[i] = gpio;
774 		pinfo->alow_flags[i] = flags & OF_GPIO_ACTIVE_LOW;
775 
776 		ret = gpio_direction_output(pinfo->gpios[i],
777 					    pinfo->alow_flags[i]);
778 		if (ret) {
779 			dev_err(dev, "can't set output direction for gpio "
780 				"#%d: %d\n", i, ret);
781 			goto err_loop;
782 		}
783 	}
784 
785 	pdata->max_chipselect = ngpios;
786 	pdata->cs_control = fsl_spi_cs_control;
787 
788 	return 0;
789 
790 err_loop:
791 	while (i >= 0) {
792 		if (gpio_is_valid(pinfo->gpios[i]))
793 			gpio_free(pinfo->gpios[i]);
794 		i--;
795 	}
796 
797 	kfree(pinfo->alow_flags);
798 	pinfo->alow_flags = NULL;
799 err_alloc_flags:
800 	kfree(pinfo->gpios);
801 	pinfo->gpios = NULL;
802 	return ret;
803 }
804 
805 static int of_fsl_spi_free_chipselects(struct device *dev)
806 {
807 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
808 	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
809 	int i;
810 
811 	if (!pinfo->gpios)
812 		return 0;
813 
814 	for (i = 0; i < pdata->max_chipselect; i++) {
815 		if (gpio_is_valid(pinfo->gpios[i]))
816 			gpio_free(pinfo->gpios[i]);
817 	}
818 
819 	kfree(pinfo->gpios);
820 	kfree(pinfo->alow_flags);
821 	return 0;
822 }
823 
824 static int of_fsl_spi_probe(struct platform_device *ofdev)
825 {
826 	struct device *dev = &ofdev->dev;
827 	struct device_node *np = ofdev->dev.of_node;
828 	struct spi_master *master;
829 	struct resource mem;
830 	int irq, type;
831 	int ret = -ENOMEM;
832 
833 	ret = of_mpc8xxx_spi_probe(ofdev);
834 	if (ret)
835 		return ret;
836 
837 	type = fsl_spi_get_type(&ofdev->dev);
838 	if (type == TYPE_FSL) {
839 		ret = of_fsl_spi_get_chipselects(dev);
840 		if (ret)
841 			goto err;
842 	}
843 
844 	ret = of_address_to_resource(np, 0, &mem);
845 	if (ret)
846 		goto err;
847 
848 	irq = irq_of_parse_and_map(np, 0);
849 	if (!irq) {
850 		ret = -EINVAL;
851 		goto err;
852 	}
853 
854 	master = fsl_spi_probe(dev, &mem, irq);
855 	if (IS_ERR(master)) {
856 		ret = PTR_ERR(master);
857 		goto err;
858 	}
859 
860 	return 0;
861 
862 err:
863 	if (type == TYPE_FSL)
864 		of_fsl_spi_free_chipselects(dev);
865 	return ret;
866 }
867 
868 static int of_fsl_spi_remove(struct platform_device *ofdev)
869 {
870 	struct spi_master *master = platform_get_drvdata(ofdev);
871 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
872 	int ret;
873 
874 	ret = mpc8xxx_spi_remove(&ofdev->dev);
875 	if (ret)
876 		return ret;
877 	if (mpc8xxx_spi->type == TYPE_FSL)
878 		of_fsl_spi_free_chipselects(&ofdev->dev);
879 	return 0;
880 }
881 
882 static struct platform_driver of_fsl_spi_driver = {
883 	.driver = {
884 		.name = "fsl_spi",
885 		.owner = THIS_MODULE,
886 		.of_match_table = of_fsl_spi_match,
887 	},
888 	.probe		= of_fsl_spi_probe,
889 	.remove		= of_fsl_spi_remove,
890 };
891 
892 #ifdef CONFIG_MPC832x_RDB
893 /*
894  * XXX XXX XXX
895  * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
896  * only. The driver should go away soon, since newer MPC8323E-RDB's device
897  * tree can work with OpenFirmware driver. But for now we support old trees
898  * as well.
899  */
900 static int plat_mpc8xxx_spi_probe(struct platform_device *pdev)
901 {
902 	struct resource *mem;
903 	int irq;
904 	struct spi_master *master;
905 
906 	if (!dev_get_platdata(&pdev->dev))
907 		return -EINVAL;
908 
909 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
910 	if (!mem)
911 		return -EINVAL;
912 
913 	irq = platform_get_irq(pdev, 0);
914 	if (irq <= 0)
915 		return -EINVAL;
916 
917 	master = fsl_spi_probe(&pdev->dev, mem, irq);
918 	return PTR_ERR_OR_ZERO(master);
919 }
920 
921 static int plat_mpc8xxx_spi_remove(struct platform_device *pdev)
922 {
923 	return mpc8xxx_spi_remove(&pdev->dev);
924 }
925 
926 MODULE_ALIAS("platform:mpc8xxx_spi");
927 static struct platform_driver mpc8xxx_spi_driver = {
928 	.probe = plat_mpc8xxx_spi_probe,
929 	.remove = plat_mpc8xxx_spi_remove,
930 	.driver = {
931 		.name = "mpc8xxx_spi",
932 		.owner = THIS_MODULE,
933 	},
934 };
935 
936 static bool legacy_driver_failed;
937 
938 static void __init legacy_driver_register(void)
939 {
940 	legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
941 }
942 
943 static void __exit legacy_driver_unregister(void)
944 {
945 	if (legacy_driver_failed)
946 		return;
947 	platform_driver_unregister(&mpc8xxx_spi_driver);
948 }
949 #else
950 static void __init legacy_driver_register(void) {}
951 static void __exit legacy_driver_unregister(void) {}
952 #endif /* CONFIG_MPC832x_RDB */
953 
954 static int __init fsl_spi_init(void)
955 {
956 	legacy_driver_register();
957 	return platform_driver_register(&of_fsl_spi_driver);
958 }
959 module_init(fsl_spi_init);
960 
961 static void __exit fsl_spi_exit(void)
962 {
963 	platform_driver_unregister(&of_fsl_spi_driver);
964 	legacy_driver_unregister();
965 }
966 module_exit(fsl_spi_exit);
967 
968 MODULE_AUTHOR("Kumar Gala");
969 MODULE_DESCRIPTION("Simple Freescale SPI Driver");
970 MODULE_LICENSE("GPL");
971