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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
49struct fsl_spi_match_data {
50	int type;
51};
52
53static struct fsl_spi_match_data of_fsl_spi_fsl_config = {
54	.type = TYPE_FSL,
55};
56
57static struct fsl_spi_match_data of_fsl_spi_grlib_config = {
58	.type = TYPE_GRLIB,
59};
60
61static 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};
72MODULE_DEVICE_TABLE(of, of_fsl_spi_match);
73
74static 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
86static 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
111static 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
138static 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
157static 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
172static 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
204static 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
222static 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
288static 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
306static 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
356static 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
422static 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
496static 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
508static 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
540static 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
562static void fsl_spi_remove(struct mpc8xxx_spi *mspi)
563{
564	iounmap(mspi->reg_base);
565	fsl_spi_cpm_free(mspi);
566}
567
568static 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
584static 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
609static 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
700unreg_master:
701	free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
702free_irq:
703	iounmap(mpc8xxx_spi->reg_base);
704err_ioremap:
705	fsl_spi_cpm_free(mpc8xxx_spi);
706err_cpm_init:
707err_probe:
708	spi_master_put(master);
709err:
710	return ERR_PTR(ret);
711}
712
713static 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
725static 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
790err_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;
799err_alloc_flags:
800	kfree(pinfo->gpios);
801	pinfo->gpios = NULL;
802	return ret;
803}
804
805static 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
824static 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
862err:
863	if (type == TYPE_FSL)
864		of_fsl_spi_free_chipselects(dev);
865	return ret;
866}
867
868static 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
882static 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 */
900static 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
921static int plat_mpc8xxx_spi_remove(struct platform_device *pdev)
922{
923	return mpc8xxx_spi_remove(&pdev->dev);
924}
925
926MODULE_ALIAS("platform:mpc8xxx_spi");
927static 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
936static bool legacy_driver_failed;
937
938static void __init legacy_driver_register(void)
939{
940	legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
941}
942
943static void __exit legacy_driver_unregister(void)
944{
945	if (legacy_driver_failed)
946		return;
947	platform_driver_unregister(&mpc8xxx_spi_driver);
948}
949#else
950static void __init legacy_driver_register(void) {}
951static void __exit legacy_driver_unregister(void) {}
952#endif /* CONFIG_MPC832x_RDB */
953
954static int __init fsl_spi_init(void)
955{
956	legacy_driver_register();
957	return platform_driver_register(&of_fsl_spi_driver);
958}
959module_init(fsl_spi_init);
960
961static void __exit fsl_spi_exit(void)
962{
963	platform_driver_unregister(&of_fsl_spi_driver);
964	legacy_driver_unregister();
965}
966module_exit(fsl_spi_exit);
967
968MODULE_AUTHOR("Kumar Gala");
969MODULE_DESCRIPTION("Simple Freescale SPI Driver");
970MODULE_LICENSE("GPL");
971