xref: /linux/drivers/spi/spi-fsl-spi.c (revision 8922a366ddd20964e3542e12f0315a8a88b3a638)
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  * This program is free software; you can redistribute  it and/or modify it
14  * under  the terms of  the GNU General  Public License as published by the
15  * Free Software Foundation;  either version 2 of the  License, or (at your
16  * option) any later version.
17  */
18 #include <linux/module.h>
19 #include <linux/types.h>
20 #include <linux/kernel.h>
21 #include <linux/interrupt.h>
22 #include <linux/delay.h>
23 #include <linux/irq.h>
24 #include <linux/spi/spi.h>
25 #include <linux/spi/spi_bitbang.h>
26 #include <linux/platform_device.h>
27 #include <linux/fsl_devices.h>
28 #include <linux/dma-mapping.h>
29 #include <linux/mm.h>
30 #include <linux/mutex.h>
31 #include <linux/of.h>
32 #include <linux/of_platform.h>
33 #include <linux/of_address.h>
34 #include <linux/of_irq.h>
35 #include <linux/gpio.h>
36 #include <linux/of_gpio.h>
37 
38 #include "spi-fsl-lib.h"
39 #include "spi-fsl-cpm.h"
40 #include "spi-fsl-spi.h"
41 
42 #define TYPE_FSL	0
43 
44 struct fsl_spi_match_data {
45 	int type;
46 };
47 
48 static struct fsl_spi_match_data of_fsl_spi_fsl_config = {
49 	.type = TYPE_FSL,
50 };
51 
52 static struct of_device_id of_fsl_spi_match[] = {
53 	{
54 		.compatible = "fsl,spi",
55 		.data = &of_fsl_spi_fsl_config,
56 	},
57 	{}
58 };
59 MODULE_DEVICE_TABLE(of, of_fsl_spi_match);
60 
61 static int fsl_spi_get_type(struct device *dev)
62 {
63 	const struct of_device_id *match;
64 
65 	if (dev->of_node) {
66 		match = of_match_node(of_fsl_spi_match, dev->of_node);
67 		if (match && match->data)
68 			return ((struct fsl_spi_match_data *)match->data)->type;
69 	}
70 	return TYPE_FSL;
71 }
72 
73 static void fsl_spi_change_mode(struct spi_device *spi)
74 {
75 	struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
76 	struct spi_mpc8xxx_cs *cs = spi->controller_state;
77 	struct fsl_spi_reg *reg_base = mspi->reg_base;
78 	__be32 __iomem *mode = &reg_base->mode;
79 	unsigned long flags;
80 
81 	if (cs->hw_mode == mpc8xxx_spi_read_reg(mode))
82 		return;
83 
84 	/* Turn off IRQs locally to minimize time that SPI is disabled. */
85 	local_irq_save(flags);
86 
87 	/* Turn off SPI unit prior changing mode */
88 	mpc8xxx_spi_write_reg(mode, cs->hw_mode & ~SPMODE_ENABLE);
89 
90 	/* When in CPM mode, we need to reinit tx and rx. */
91 	if (mspi->flags & SPI_CPM_MODE) {
92 		fsl_spi_cpm_reinit_txrx(mspi);
93 	}
94 	mpc8xxx_spi_write_reg(mode, cs->hw_mode);
95 	local_irq_restore(flags);
96 }
97 
98 static void fsl_spi_chipselect(struct spi_device *spi, int value)
99 {
100 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
101 	struct fsl_spi_platform_data *pdata;
102 	bool pol = spi->mode & SPI_CS_HIGH;
103 	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
104 
105 	pdata = spi->dev.parent->parent->platform_data;
106 
107 	if (value == BITBANG_CS_INACTIVE) {
108 		if (pdata->cs_control)
109 			pdata->cs_control(spi, !pol);
110 	}
111 
112 	if (value == BITBANG_CS_ACTIVE) {
113 		mpc8xxx_spi->rx_shift = cs->rx_shift;
114 		mpc8xxx_spi->tx_shift = cs->tx_shift;
115 		mpc8xxx_spi->get_rx = cs->get_rx;
116 		mpc8xxx_spi->get_tx = cs->get_tx;
117 
118 		fsl_spi_change_mode(spi);
119 
120 		if (pdata->cs_control)
121 			pdata->cs_control(spi, pol);
122 	}
123 }
124 
125 static void fsl_spi_qe_cpu_set_shifts(u32 *rx_shift, u32 *tx_shift,
126 				      int bits_per_word, int msb_first)
127 {
128 	*rx_shift = 0;
129 	*tx_shift = 0;
130 	if (msb_first) {
131 		if (bits_per_word <= 8) {
132 			*rx_shift = 16;
133 			*tx_shift = 24;
134 		} else if (bits_per_word <= 16) {
135 			*rx_shift = 16;
136 			*tx_shift = 16;
137 		}
138 	} else {
139 		if (bits_per_word <= 8)
140 			*rx_shift = 8;
141 	}
142 }
143 
144 static int mspi_apply_cpu_mode_quirks(struct spi_mpc8xxx_cs *cs,
145 				struct spi_device *spi,
146 				struct mpc8xxx_spi *mpc8xxx_spi,
147 				int bits_per_word)
148 {
149 	cs->rx_shift = 0;
150 	cs->tx_shift = 0;
151 	if (bits_per_word <= 8) {
152 		cs->get_rx = mpc8xxx_spi_rx_buf_u8;
153 		cs->get_tx = mpc8xxx_spi_tx_buf_u8;
154 	} else if (bits_per_word <= 16) {
155 		cs->get_rx = mpc8xxx_spi_rx_buf_u16;
156 		cs->get_tx = mpc8xxx_spi_tx_buf_u16;
157 	} else if (bits_per_word <= 32) {
158 		cs->get_rx = mpc8xxx_spi_rx_buf_u32;
159 		cs->get_tx = mpc8xxx_spi_tx_buf_u32;
160 	} else
161 		return -EINVAL;
162 
163 	if (mpc8xxx_spi->set_shifts)
164 		mpc8xxx_spi->set_shifts(&cs->rx_shift, &cs->tx_shift,
165 					bits_per_word,
166 					!(spi->mode & SPI_LSB_FIRST));
167 
168 	mpc8xxx_spi->rx_shift = cs->rx_shift;
169 	mpc8xxx_spi->tx_shift = cs->tx_shift;
170 	mpc8xxx_spi->get_rx = cs->get_rx;
171 	mpc8xxx_spi->get_tx = cs->get_tx;
172 
173 	return bits_per_word;
174 }
175 
176 static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs,
177 				struct spi_device *spi,
178 				int bits_per_word)
179 {
180 	/* QE uses Little Endian for words > 8
181 	 * so transform all words > 8 into 8 bits
182 	 * Unfortnatly that doesn't work for LSB so
183 	 * reject these for now */
184 	/* Note: 32 bits word, LSB works iff
185 	 * tfcr/rfcr is set to CPMFCR_GBL */
186 	if (spi->mode & SPI_LSB_FIRST &&
187 	    bits_per_word > 8)
188 		return -EINVAL;
189 	if (bits_per_word > 8)
190 		return 8; /* pretend its 8 bits */
191 	return bits_per_word;
192 }
193 
194 static int fsl_spi_setup_transfer(struct spi_device *spi,
195 					struct spi_transfer *t)
196 {
197 	struct mpc8xxx_spi *mpc8xxx_spi;
198 	int bits_per_word = 0;
199 	u8 pm;
200 	u32 hz = 0;
201 	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
202 
203 	mpc8xxx_spi = spi_master_get_devdata(spi->master);
204 
205 	if (t) {
206 		bits_per_word = t->bits_per_word;
207 		hz = t->speed_hz;
208 	}
209 
210 	/* spi_transfer level calls that work per-word */
211 	if (!bits_per_word)
212 		bits_per_word = spi->bits_per_word;
213 
214 	/* Make sure its a bit width we support [4..16, 32] */
215 	if ((bits_per_word < 4)
216 	    || ((bits_per_word > 16) && (bits_per_word != 32))
217 	    || (bits_per_word > mpc8xxx_spi->max_bits_per_word))
218 		return -EINVAL;
219 
220 	if (!hz)
221 		hz = spi->max_speed_hz;
222 
223 	if (!(mpc8xxx_spi->flags & SPI_CPM_MODE))
224 		bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi,
225 							   mpc8xxx_spi,
226 							   bits_per_word);
227 	else if (mpc8xxx_spi->flags & SPI_QE)
228 		bits_per_word = mspi_apply_qe_mode_quirks(cs, spi,
229 							  bits_per_word);
230 
231 	if (bits_per_word < 0)
232 		return bits_per_word;
233 
234 	if (bits_per_word == 32)
235 		bits_per_word = 0;
236 	else
237 		bits_per_word = bits_per_word - 1;
238 
239 	/* mask out bits we are going to set */
240 	cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16
241 				  | SPMODE_PM(0xF));
242 
243 	cs->hw_mode |= SPMODE_LEN(bits_per_word);
244 
245 	if ((mpc8xxx_spi->spibrg / hz) > 64) {
246 		cs->hw_mode |= SPMODE_DIV16;
247 		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
248 
249 		WARN_ONCE(pm > 16, "%s: Requested speed is too low: %d Hz. "
250 			  "Will use %d Hz instead.\n", dev_name(&spi->dev),
251 			  hz, mpc8xxx_spi->spibrg / 1024);
252 		if (pm > 16)
253 			pm = 16;
254 	} else {
255 		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
256 	}
257 	if (pm)
258 		pm--;
259 
260 	cs->hw_mode |= SPMODE_PM(pm);
261 
262 	fsl_spi_change_mode(spi);
263 	return 0;
264 }
265 
266 static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi,
267 				struct spi_transfer *t, unsigned int len)
268 {
269 	u32 word;
270 	struct fsl_spi_reg *reg_base = mspi->reg_base;
271 
272 	mspi->count = len;
273 
274 	/* enable rx ints */
275 	mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
276 
277 	/* transmit word */
278 	word = mspi->get_tx(mspi);
279 	mpc8xxx_spi_write_reg(&reg_base->transmit, word);
280 
281 	return 0;
282 }
283 
284 static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t,
285 			    bool is_dma_mapped)
286 {
287 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
288 	struct fsl_spi_reg *reg_base;
289 	unsigned int len = t->len;
290 	u8 bits_per_word;
291 	int ret;
292 
293 	reg_base = mpc8xxx_spi->reg_base;
294 	bits_per_word = spi->bits_per_word;
295 	if (t->bits_per_word)
296 		bits_per_word = t->bits_per_word;
297 
298 	if (bits_per_word > 8) {
299 		/* invalid length? */
300 		if (len & 1)
301 			return -EINVAL;
302 		len /= 2;
303 	}
304 	if (bits_per_word > 16) {
305 		/* invalid length? */
306 		if (len & 1)
307 			return -EINVAL;
308 		len /= 2;
309 	}
310 
311 	mpc8xxx_spi->tx = t->tx_buf;
312 	mpc8xxx_spi->rx = t->rx_buf;
313 
314 	INIT_COMPLETION(mpc8xxx_spi->done);
315 
316 	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
317 		ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped);
318 	else
319 		ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len);
320 	if (ret)
321 		return ret;
322 
323 	wait_for_completion(&mpc8xxx_spi->done);
324 
325 	/* disable rx ints */
326 	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
327 
328 	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
329 		fsl_spi_cpm_bufs_complete(mpc8xxx_spi);
330 
331 	return mpc8xxx_spi->count;
332 }
333 
334 static void fsl_spi_do_one_msg(struct spi_message *m)
335 {
336 	struct spi_device *spi = m->spi;
337 	struct spi_transfer *t;
338 	unsigned int cs_change;
339 	const int nsecs = 50;
340 	int status;
341 
342 	cs_change = 1;
343 	status = 0;
344 	list_for_each_entry(t, &m->transfers, transfer_list) {
345 		if (t->bits_per_word || t->speed_hz) {
346 			/* Don't allow changes if CS is active */
347 			status = -EINVAL;
348 
349 			if (cs_change)
350 				status = fsl_spi_setup_transfer(spi, t);
351 			if (status < 0)
352 				break;
353 		}
354 
355 		if (cs_change) {
356 			fsl_spi_chipselect(spi, BITBANG_CS_ACTIVE);
357 			ndelay(nsecs);
358 		}
359 		cs_change = t->cs_change;
360 		if (t->len)
361 			status = fsl_spi_bufs(spi, t, m->is_dma_mapped);
362 		if (status) {
363 			status = -EMSGSIZE;
364 			break;
365 		}
366 		m->actual_length += t->len;
367 
368 		if (t->delay_usecs)
369 			udelay(t->delay_usecs);
370 
371 		if (cs_change) {
372 			ndelay(nsecs);
373 			fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
374 			ndelay(nsecs);
375 		}
376 	}
377 
378 	m->status = status;
379 	m->complete(m->context);
380 
381 	if (status || !cs_change) {
382 		ndelay(nsecs);
383 		fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
384 	}
385 
386 	fsl_spi_setup_transfer(spi, NULL);
387 }
388 
389 static int fsl_spi_setup(struct spi_device *spi)
390 {
391 	struct mpc8xxx_spi *mpc8xxx_spi;
392 	struct fsl_spi_reg *reg_base;
393 	int retval;
394 	u32 hw_mode;
395 	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
396 
397 	if (!spi->max_speed_hz)
398 		return -EINVAL;
399 
400 	if (!cs) {
401 		cs = kzalloc(sizeof *cs, GFP_KERNEL);
402 		if (!cs)
403 			return -ENOMEM;
404 		spi->controller_state = cs;
405 	}
406 	mpc8xxx_spi = spi_master_get_devdata(spi->master);
407 
408 	reg_base = mpc8xxx_spi->reg_base;
409 
410 	hw_mode = cs->hw_mode; /* Save original settings */
411 	cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
412 	/* mask out bits we are going to set */
413 	cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
414 			 | SPMODE_REV | SPMODE_LOOP);
415 
416 	if (spi->mode & SPI_CPHA)
417 		cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
418 	if (spi->mode & SPI_CPOL)
419 		cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
420 	if (!(spi->mode & SPI_LSB_FIRST))
421 		cs->hw_mode |= SPMODE_REV;
422 	if (spi->mode & SPI_LOOP)
423 		cs->hw_mode |= SPMODE_LOOP;
424 
425 	retval = fsl_spi_setup_transfer(spi, NULL);
426 	if (retval < 0) {
427 		cs->hw_mode = hw_mode; /* Restore settings */
428 		return retval;
429 	}
430 
431 	/* Initialize chipselect - might be active for SPI_CS_HIGH mode */
432 	fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
433 
434 	return 0;
435 }
436 
437 static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
438 {
439 	struct fsl_spi_reg *reg_base = mspi->reg_base;
440 
441 	/* We need handle RX first */
442 	if (events & SPIE_NE) {
443 		u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
444 
445 		if (mspi->rx)
446 			mspi->get_rx(rx_data, mspi);
447 	}
448 
449 	if ((events & SPIE_NF) == 0)
450 		/* spin until TX is done */
451 		while (((events =
452 			mpc8xxx_spi_read_reg(&reg_base->event)) &
453 						SPIE_NF) == 0)
454 			cpu_relax();
455 
456 	/* Clear the events */
457 	mpc8xxx_spi_write_reg(&reg_base->event, events);
458 
459 	mspi->count -= 1;
460 	if (mspi->count) {
461 		u32 word = mspi->get_tx(mspi);
462 
463 		mpc8xxx_spi_write_reg(&reg_base->transmit, word);
464 	} else {
465 		complete(&mspi->done);
466 	}
467 }
468 
469 static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
470 {
471 	struct mpc8xxx_spi *mspi = context_data;
472 	irqreturn_t ret = IRQ_NONE;
473 	u32 events;
474 	struct fsl_spi_reg *reg_base = mspi->reg_base;
475 
476 	/* Get interrupt events(tx/rx) */
477 	events = mpc8xxx_spi_read_reg(&reg_base->event);
478 	if (events)
479 		ret = IRQ_HANDLED;
480 
481 	dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
482 
483 	if (mspi->flags & SPI_CPM_MODE)
484 		fsl_spi_cpm_irq(mspi, events);
485 	else
486 		fsl_spi_cpu_irq(mspi, events);
487 
488 	return ret;
489 }
490 
491 static void fsl_spi_remove(struct mpc8xxx_spi *mspi)
492 {
493 	iounmap(mspi->reg_base);
494 	fsl_spi_cpm_free(mspi);
495 }
496 
497 static struct spi_master * fsl_spi_probe(struct device *dev,
498 		struct resource *mem, unsigned int irq)
499 {
500 	struct fsl_spi_platform_data *pdata = dev->platform_data;
501 	struct spi_master *master;
502 	struct mpc8xxx_spi *mpc8xxx_spi;
503 	struct fsl_spi_reg *reg_base;
504 	u32 regval;
505 	int ret = 0;
506 
507 	master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
508 	if (master == NULL) {
509 		ret = -ENOMEM;
510 		goto err;
511 	}
512 
513 	dev_set_drvdata(dev, master);
514 
515 	ret = mpc8xxx_spi_probe(dev, mem, irq);
516 	if (ret)
517 		goto err_probe;
518 
519 	master->setup = fsl_spi_setup;
520 
521 	mpc8xxx_spi = spi_master_get_devdata(master);
522 	mpc8xxx_spi->spi_do_one_msg = fsl_spi_do_one_msg;
523 	mpc8xxx_spi->spi_remove = fsl_spi_remove;
524 	mpc8xxx_spi->max_bits_per_word = 32;
525 	mpc8xxx_spi->type = fsl_spi_get_type(dev);
526 
527 	ret = fsl_spi_cpm_init(mpc8xxx_spi);
528 	if (ret)
529 		goto err_cpm_init;
530 
531 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
532 		mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts;
533 
534 	if (mpc8xxx_spi->set_shifts)
535 		/* 8 bits per word and MSB first */
536 		mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift,
537 					&mpc8xxx_spi->tx_shift, 8, 1);
538 
539 	mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem));
540 	if (mpc8xxx_spi->reg_base == NULL) {
541 		ret = -ENOMEM;
542 		goto err_ioremap;
543 	}
544 
545 	/* Register for SPI Interrupt */
546 	ret = request_irq(mpc8xxx_spi->irq, fsl_spi_irq,
547 			  0, "fsl_spi", mpc8xxx_spi);
548 
549 	if (ret != 0)
550 		goto free_irq;
551 
552 	reg_base = mpc8xxx_spi->reg_base;
553 
554 	/* SPI controller initializations */
555 	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
556 	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
557 	mpc8xxx_spi_write_reg(&reg_base->command, 0);
558 	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
559 
560 	/* Enable SPI interface */
561 	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
562 	if (mpc8xxx_spi->max_bits_per_word < 8) {
563 		regval &= ~SPMODE_LEN(0xF);
564 		regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1);
565 	}
566 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
567 		regval |= SPMODE_OP;
568 
569 	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
570 
571 	ret = spi_register_master(master);
572 	if (ret < 0)
573 		goto unreg_master;
574 
575 	dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
576 		 mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
577 
578 	return master;
579 
580 unreg_master:
581 	free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
582 free_irq:
583 	iounmap(mpc8xxx_spi->reg_base);
584 err_ioremap:
585 	fsl_spi_cpm_free(mpc8xxx_spi);
586 err_cpm_init:
587 err_probe:
588 	spi_master_put(master);
589 err:
590 	return ERR_PTR(ret);
591 }
592 
593 static void fsl_spi_cs_control(struct spi_device *spi, bool on)
594 {
595 	struct device *dev = spi->dev.parent->parent;
596 	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(dev->platform_data);
597 	u16 cs = spi->chip_select;
598 	int gpio = pinfo->gpios[cs];
599 	bool alow = pinfo->alow_flags[cs];
600 
601 	gpio_set_value(gpio, on ^ alow);
602 }
603 
604 static int of_fsl_spi_get_chipselects(struct device *dev)
605 {
606 	struct device_node *np = dev->of_node;
607 	struct fsl_spi_platform_data *pdata = dev->platform_data;
608 	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
609 	int ngpios;
610 	int i = 0;
611 	int ret;
612 
613 	ngpios = of_gpio_count(np);
614 	if (ngpios <= 0) {
615 		/*
616 		 * SPI w/o chip-select line. One SPI device is still permitted
617 		 * though.
618 		 */
619 		pdata->max_chipselect = 1;
620 		return 0;
621 	}
622 
623 	pinfo->gpios = kmalloc(ngpios * sizeof(*pinfo->gpios), GFP_KERNEL);
624 	if (!pinfo->gpios)
625 		return -ENOMEM;
626 	memset(pinfo->gpios, -1, ngpios * sizeof(*pinfo->gpios));
627 
628 	pinfo->alow_flags = kzalloc(ngpios * sizeof(*pinfo->alow_flags),
629 				    GFP_KERNEL);
630 	if (!pinfo->alow_flags) {
631 		ret = -ENOMEM;
632 		goto err_alloc_flags;
633 	}
634 
635 	for (; i < ngpios; i++) {
636 		int gpio;
637 		enum of_gpio_flags flags;
638 
639 		gpio = of_get_gpio_flags(np, i, &flags);
640 		if (!gpio_is_valid(gpio)) {
641 			dev_err(dev, "invalid gpio #%d: %d\n", i, gpio);
642 			ret = gpio;
643 			goto err_loop;
644 		}
645 
646 		ret = gpio_request(gpio, dev_name(dev));
647 		if (ret) {
648 			dev_err(dev, "can't request gpio #%d: %d\n", i, ret);
649 			goto err_loop;
650 		}
651 
652 		pinfo->gpios[i] = gpio;
653 		pinfo->alow_flags[i] = flags & OF_GPIO_ACTIVE_LOW;
654 
655 		ret = gpio_direction_output(pinfo->gpios[i],
656 					    pinfo->alow_flags[i]);
657 		if (ret) {
658 			dev_err(dev, "can't set output direction for gpio "
659 				"#%d: %d\n", i, ret);
660 			goto err_loop;
661 		}
662 	}
663 
664 	pdata->max_chipselect = ngpios;
665 	pdata->cs_control = fsl_spi_cs_control;
666 
667 	return 0;
668 
669 err_loop:
670 	while (i >= 0) {
671 		if (gpio_is_valid(pinfo->gpios[i]))
672 			gpio_free(pinfo->gpios[i]);
673 		i--;
674 	}
675 
676 	kfree(pinfo->alow_flags);
677 	pinfo->alow_flags = NULL;
678 err_alloc_flags:
679 	kfree(pinfo->gpios);
680 	pinfo->gpios = NULL;
681 	return ret;
682 }
683 
684 static int of_fsl_spi_free_chipselects(struct device *dev)
685 {
686 	struct fsl_spi_platform_data *pdata = dev->platform_data;
687 	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
688 	int i;
689 
690 	if (!pinfo->gpios)
691 		return 0;
692 
693 	for (i = 0; i < pdata->max_chipselect; i++) {
694 		if (gpio_is_valid(pinfo->gpios[i]))
695 			gpio_free(pinfo->gpios[i]);
696 	}
697 
698 	kfree(pinfo->gpios);
699 	kfree(pinfo->alow_flags);
700 	return 0;
701 }
702 
703 static int of_fsl_spi_probe(struct platform_device *ofdev)
704 {
705 	struct device *dev = &ofdev->dev;
706 	struct device_node *np = ofdev->dev.of_node;
707 	struct spi_master *master;
708 	struct resource mem;
709 	int irq;
710 	int ret = -ENOMEM;
711 
712 	ret = of_mpc8xxx_spi_probe(ofdev);
713 	if (ret)
714 		return ret;
715 
716 	ret = of_fsl_spi_get_chipselects(dev);
717 	if (ret)
718 		goto err;
719 
720 	ret = of_address_to_resource(np, 0, &mem);
721 	if (ret)
722 		goto err;
723 
724 	irq = irq_of_parse_and_map(np, 0);
725 	if (!irq) {
726 		ret = -EINVAL;
727 		goto err;
728 	}
729 
730 	master = fsl_spi_probe(dev, &mem, irq);
731 	if (IS_ERR(master)) {
732 		ret = PTR_ERR(master);
733 		goto err;
734 	}
735 
736 	return 0;
737 
738 err:
739 	of_fsl_spi_free_chipselects(dev);
740 	return ret;
741 }
742 
743 static int of_fsl_spi_remove(struct platform_device *ofdev)
744 {
745 	int ret;
746 
747 	ret = mpc8xxx_spi_remove(&ofdev->dev);
748 	if (ret)
749 		return ret;
750 	of_fsl_spi_free_chipselects(&ofdev->dev);
751 	return 0;
752 }
753 
754 static struct platform_driver of_fsl_spi_driver = {
755 	.driver = {
756 		.name = "fsl_spi",
757 		.owner = THIS_MODULE,
758 		.of_match_table = of_fsl_spi_match,
759 	},
760 	.probe		= of_fsl_spi_probe,
761 	.remove		= of_fsl_spi_remove,
762 };
763 
764 #ifdef CONFIG_MPC832x_RDB
765 /*
766  * XXX XXX XXX
767  * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
768  * only. The driver should go away soon, since newer MPC8323E-RDB's device
769  * tree can work with OpenFirmware driver. But for now we support old trees
770  * as well.
771  */
772 static int plat_mpc8xxx_spi_probe(struct platform_device *pdev)
773 {
774 	struct resource *mem;
775 	int irq;
776 	struct spi_master *master;
777 
778 	if (!pdev->dev.platform_data)
779 		return -EINVAL;
780 
781 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
782 	if (!mem)
783 		return -EINVAL;
784 
785 	irq = platform_get_irq(pdev, 0);
786 	if (irq <= 0)
787 		return -EINVAL;
788 
789 	master = fsl_spi_probe(&pdev->dev, mem, irq);
790 	return PTR_RET(master);
791 }
792 
793 static int plat_mpc8xxx_spi_remove(struct platform_device *pdev)
794 {
795 	return mpc8xxx_spi_remove(&pdev->dev);
796 }
797 
798 MODULE_ALIAS("platform:mpc8xxx_spi");
799 static struct platform_driver mpc8xxx_spi_driver = {
800 	.probe = plat_mpc8xxx_spi_probe,
801 	.remove = plat_mpc8xxx_spi_remove,
802 	.driver = {
803 		.name = "mpc8xxx_spi",
804 		.owner = THIS_MODULE,
805 	},
806 };
807 
808 static bool legacy_driver_failed;
809 
810 static void __init legacy_driver_register(void)
811 {
812 	legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
813 }
814 
815 static void __exit legacy_driver_unregister(void)
816 {
817 	if (legacy_driver_failed)
818 		return;
819 	platform_driver_unregister(&mpc8xxx_spi_driver);
820 }
821 #else
822 static void __init legacy_driver_register(void) {}
823 static void __exit legacy_driver_unregister(void) {}
824 #endif /* CONFIG_MPC832x_RDB */
825 
826 static int __init fsl_spi_init(void)
827 {
828 	legacy_driver_register();
829 	return platform_driver_register(&of_fsl_spi_driver);
830 }
831 module_init(fsl_spi_init);
832 
833 static void __exit fsl_spi_exit(void)
834 {
835 	platform_driver_unregister(&of_fsl_spi_driver);
836 	legacy_driver_unregister();
837 }
838 module_exit(fsl_spi_exit);
839 
840 MODULE_AUTHOR("Kumar Gala");
841 MODULE_DESCRIPTION("Simple Freescale SPI Driver");
842 MODULE_LICENSE("GPL");
843