1/*
2 * Freescale eSPI controller driver.
3 *
4 * Copyright 2010 Freescale Semiconductor, Inc.
5 *
6 * This program is free software; you can redistribute  it and/or modify it
7 * under  the terms of  the GNU General  Public License as published by the
8 * Free Software Foundation;  either version 2 of the  License, or (at your
9 * option) any later version.
10 */
11#include <linux/delay.h>
12#include <linux/err.h>
13#include <linux/fsl_devices.h>
14#include <linux/interrupt.h>
15#include <linux/irq.h>
16#include <linux/module.h>
17#include <linux/mm.h>
18#include <linux/of.h>
19#include <linux/of_address.h>
20#include <linux/of_irq.h>
21#include <linux/of_platform.h>
22#include <linux/platform_device.h>
23#include <linux/spi/spi.h>
24#include <sysdev/fsl_soc.h>
25
26#include "spi-fsl-lib.h"
27
28/* eSPI Controller registers */
29struct fsl_espi_reg {
30	__be32 mode;		/* 0x000 - eSPI mode register */
31	__be32 event;		/* 0x004 - eSPI event register */
32	__be32 mask;		/* 0x008 - eSPI mask register */
33	__be32 command;		/* 0x00c - eSPI command register */
34	__be32 transmit;	/* 0x010 - eSPI transmit FIFO access register*/
35	__be32 receive;		/* 0x014 - eSPI receive FIFO access register*/
36	u8 res[8];		/* 0x018 - 0x01c reserved */
37	__be32 csmode[4];	/* 0x020 - 0x02c eSPI cs mode register */
38};
39
40struct fsl_espi_transfer {
41	const void *tx_buf;
42	void *rx_buf;
43	unsigned len;
44	unsigned n_tx;
45	unsigned n_rx;
46	unsigned actual_length;
47	int status;
48};
49
50/* eSPI Controller mode register definitions */
51#define SPMODE_ENABLE		(1 << 31)
52#define SPMODE_LOOP		(1 << 30)
53#define SPMODE_TXTHR(x)		((x) << 8)
54#define SPMODE_RXTHR(x)		((x) << 0)
55
56/* eSPI Controller CS mode register definitions */
57#define CSMODE_CI_INACTIVEHIGH	(1 << 31)
58#define CSMODE_CP_BEGIN_EDGECLK	(1 << 30)
59#define CSMODE_REV		(1 << 29)
60#define CSMODE_DIV16		(1 << 28)
61#define CSMODE_PM(x)		((x) << 24)
62#define CSMODE_POL_1		(1 << 20)
63#define CSMODE_LEN(x)		((x) << 16)
64#define CSMODE_BEF(x)		((x) << 12)
65#define CSMODE_AFT(x)		((x) << 8)
66#define CSMODE_CG(x)		((x) << 3)
67
68/* Default mode/csmode for eSPI controller */
69#define SPMODE_INIT_VAL (SPMODE_TXTHR(4) | SPMODE_RXTHR(3))
70#define CSMODE_INIT_VAL (CSMODE_POL_1 | CSMODE_BEF(0) \
71		| CSMODE_AFT(0) | CSMODE_CG(1))
72
73/* SPIE register values */
74#define	SPIE_NE		0x00000200	/* Not empty */
75#define	SPIE_NF		0x00000100	/* Not full */
76
77/* SPIM register values */
78#define	SPIM_NE		0x00000200	/* Not empty */
79#define	SPIM_NF		0x00000100	/* Not full */
80#define SPIE_RXCNT(reg)     ((reg >> 24) & 0x3F)
81#define SPIE_TXCNT(reg)     ((reg >> 16) & 0x3F)
82
83/* SPCOM register values */
84#define SPCOM_CS(x)		((x) << 30)
85#define SPCOM_TRANLEN(x)	((x) << 0)
86#define	SPCOM_TRANLEN_MAX	0xFFFF	/* Max transaction length */
87
88static void fsl_espi_change_mode(struct spi_device *spi)
89{
90	struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
91	struct spi_mpc8xxx_cs *cs = spi->controller_state;
92	struct fsl_espi_reg *reg_base = mspi->reg_base;
93	__be32 __iomem *mode = &reg_base->csmode[spi->chip_select];
94	__be32 __iomem *espi_mode = &reg_base->mode;
95	u32 tmp;
96	unsigned long flags;
97
98	/* Turn off IRQs locally to minimize time that SPI is disabled. */
99	local_irq_save(flags);
100
101	/* Turn off SPI unit prior changing mode */
102	tmp = mpc8xxx_spi_read_reg(espi_mode);
103	mpc8xxx_spi_write_reg(espi_mode, tmp & ~SPMODE_ENABLE);
104	mpc8xxx_spi_write_reg(mode, cs->hw_mode);
105	mpc8xxx_spi_write_reg(espi_mode, tmp);
106
107	local_irq_restore(flags);
108}
109
110static u32 fsl_espi_tx_buf_lsb(struct mpc8xxx_spi *mpc8xxx_spi)
111{
112	u32 data;
113	u16 data_h;
114	u16 data_l;
115	const u32 *tx = mpc8xxx_spi->tx;
116
117	if (!tx)
118		return 0;
119
120	data = *tx++ << mpc8xxx_spi->tx_shift;
121	data_l = data & 0xffff;
122	data_h = (data >> 16) & 0xffff;
123	swab16s(&data_l);
124	swab16s(&data_h);
125	data = data_h | data_l;
126
127	mpc8xxx_spi->tx = tx;
128	return data;
129}
130
131static int fsl_espi_setup_transfer(struct spi_device *spi,
132					struct spi_transfer *t)
133{
134	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
135	int bits_per_word = 0;
136	u8 pm;
137	u32 hz = 0;
138	struct spi_mpc8xxx_cs *cs = spi->controller_state;
139
140	if (t) {
141		bits_per_word = t->bits_per_word;
142		hz = t->speed_hz;
143	}
144
145	/* spi_transfer level calls that work per-word */
146	if (!bits_per_word)
147		bits_per_word = spi->bits_per_word;
148
149	if (!hz)
150		hz = spi->max_speed_hz;
151
152	cs->rx_shift = 0;
153	cs->tx_shift = 0;
154	cs->get_rx = mpc8xxx_spi_rx_buf_u32;
155	cs->get_tx = mpc8xxx_spi_tx_buf_u32;
156	if (bits_per_word <= 8) {
157		cs->rx_shift = 8 - bits_per_word;
158	} else {
159		cs->rx_shift = 16 - bits_per_word;
160		if (spi->mode & SPI_LSB_FIRST)
161			cs->get_tx = fsl_espi_tx_buf_lsb;
162	}
163
164	mpc8xxx_spi->rx_shift = cs->rx_shift;
165	mpc8xxx_spi->tx_shift = cs->tx_shift;
166	mpc8xxx_spi->get_rx = cs->get_rx;
167	mpc8xxx_spi->get_tx = cs->get_tx;
168
169	bits_per_word = bits_per_word - 1;
170
171	/* mask out bits we are going to set */
172	cs->hw_mode &= ~(CSMODE_LEN(0xF) | CSMODE_DIV16 | CSMODE_PM(0xF));
173
174	cs->hw_mode |= CSMODE_LEN(bits_per_word);
175
176	if ((mpc8xxx_spi->spibrg / hz) > 64) {
177		cs->hw_mode |= CSMODE_DIV16;
178		pm = DIV_ROUND_UP(mpc8xxx_spi->spibrg, hz * 16 * 4);
179
180		WARN_ONCE(pm > 33, "%s: Requested speed is too low: %d Hz. "
181			  "Will use %d Hz instead.\n", dev_name(&spi->dev),
182				hz, mpc8xxx_spi->spibrg / (4 * 16 * (32 + 1)));
183		if (pm > 33)
184			pm = 33;
185	} else {
186		pm = DIV_ROUND_UP(mpc8xxx_spi->spibrg, hz * 4);
187	}
188	if (pm)
189		pm--;
190	if (pm < 2)
191		pm = 2;
192
193	cs->hw_mode |= CSMODE_PM(pm);
194
195	fsl_espi_change_mode(spi);
196	return 0;
197}
198
199static int fsl_espi_cpu_bufs(struct mpc8xxx_spi *mspi, struct spi_transfer *t,
200		unsigned int len)
201{
202	u32 word;
203	struct fsl_espi_reg *reg_base = mspi->reg_base;
204
205	mspi->count = len;
206
207	/* enable rx ints */
208	mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
209
210	/* transmit word */
211	word = mspi->get_tx(mspi);
212	mpc8xxx_spi_write_reg(&reg_base->transmit, word);
213
214	return 0;
215}
216
217static int fsl_espi_bufs(struct spi_device *spi, struct spi_transfer *t)
218{
219	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
220	struct fsl_espi_reg *reg_base = mpc8xxx_spi->reg_base;
221	unsigned int len = t->len;
222	int ret;
223
224	mpc8xxx_spi->len = t->len;
225	len = roundup(len, 4) / 4;
226
227	mpc8xxx_spi->tx = t->tx_buf;
228	mpc8xxx_spi->rx = t->rx_buf;
229
230	reinit_completion(&mpc8xxx_spi->done);
231
232	/* Set SPCOM[CS] and SPCOM[TRANLEN] field */
233	if ((t->len - 1) > SPCOM_TRANLEN_MAX) {
234		dev_err(mpc8xxx_spi->dev, "Transaction length (%d)"
235				" beyond the SPCOM[TRANLEN] field\n", t->len);
236		return -EINVAL;
237	}
238	mpc8xxx_spi_write_reg(&reg_base->command,
239		(SPCOM_CS(spi->chip_select) | SPCOM_TRANLEN(t->len - 1)));
240
241	ret = fsl_espi_cpu_bufs(mpc8xxx_spi, t, len);
242	if (ret)
243		return ret;
244
245	wait_for_completion(&mpc8xxx_spi->done);
246
247	/* disable rx ints */
248	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
249
250	return mpc8xxx_spi->count;
251}
252
253static inline void fsl_espi_addr2cmd(unsigned int addr, u8 *cmd)
254{
255	if (cmd) {
256		cmd[1] = (u8)(addr >> 16);
257		cmd[2] = (u8)(addr >> 8);
258		cmd[3] = (u8)(addr >> 0);
259	}
260}
261
262static inline unsigned int fsl_espi_cmd2addr(u8 *cmd)
263{
264	if (cmd)
265		return cmd[1] << 16 | cmd[2] << 8 | cmd[3] << 0;
266
267	return 0;
268}
269
270static void fsl_espi_do_trans(struct spi_message *m,
271				struct fsl_espi_transfer *tr)
272{
273	struct spi_device *spi = m->spi;
274	struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
275	struct fsl_espi_transfer *espi_trans = tr;
276	struct spi_message message;
277	struct spi_transfer *t, *first, trans;
278	int status = 0;
279
280	spi_message_init(&message);
281	memset(&trans, 0, sizeof(trans));
282
283	first = list_first_entry(&m->transfers, struct spi_transfer,
284			transfer_list);
285	list_for_each_entry(t, &m->transfers, transfer_list) {
286		if ((first->bits_per_word != t->bits_per_word) ||
287			(first->speed_hz != t->speed_hz)) {
288			espi_trans->status = -EINVAL;
289			dev_err(mspi->dev,
290				"bits_per_word/speed_hz should be same for the same SPI transfer\n");
291			return;
292		}
293
294		trans.speed_hz = t->speed_hz;
295		trans.bits_per_word = t->bits_per_word;
296		trans.delay_usecs = max(first->delay_usecs, t->delay_usecs);
297	}
298
299	trans.len = espi_trans->len;
300	trans.tx_buf = espi_trans->tx_buf;
301	trans.rx_buf = espi_trans->rx_buf;
302	spi_message_add_tail(&trans, &message);
303
304	list_for_each_entry(t, &message.transfers, transfer_list) {
305		if (t->bits_per_word || t->speed_hz) {
306			status = -EINVAL;
307
308			status = fsl_espi_setup_transfer(spi, t);
309			if (status < 0)
310				break;
311		}
312
313		if (t->len)
314			status = fsl_espi_bufs(spi, t);
315
316		if (status) {
317			status = -EMSGSIZE;
318			break;
319		}
320
321		if (t->delay_usecs)
322			udelay(t->delay_usecs);
323	}
324
325	espi_trans->status = status;
326	fsl_espi_setup_transfer(spi, NULL);
327}
328
329static void fsl_espi_cmd_trans(struct spi_message *m,
330				struct fsl_espi_transfer *trans, u8 *rx_buff)
331{
332	struct spi_transfer *t;
333	u8 *local_buf;
334	int i = 0;
335	struct fsl_espi_transfer *espi_trans = trans;
336
337	local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
338	if (!local_buf) {
339		espi_trans->status = -ENOMEM;
340		return;
341	}
342
343	list_for_each_entry(t, &m->transfers, transfer_list) {
344		if (t->tx_buf) {
345			memcpy(local_buf + i, t->tx_buf, t->len);
346			i += t->len;
347		}
348	}
349
350	espi_trans->tx_buf = local_buf;
351	espi_trans->rx_buf = local_buf;
352	fsl_espi_do_trans(m, espi_trans);
353
354	espi_trans->actual_length = espi_trans->len;
355	kfree(local_buf);
356}
357
358static void fsl_espi_rw_trans(struct spi_message *m,
359				struct fsl_espi_transfer *trans, u8 *rx_buff)
360{
361	struct fsl_espi_transfer *espi_trans = trans;
362	unsigned int total_len = espi_trans->len;
363	struct spi_transfer *t;
364	u8 *local_buf;
365	u8 *rx_buf = rx_buff;
366	unsigned int trans_len;
367	unsigned int addr;
368	unsigned int tx_only;
369	unsigned int rx_pos = 0;
370	unsigned int pos;
371	int i, loop;
372
373	local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
374	if (!local_buf) {
375		espi_trans->status = -ENOMEM;
376		return;
377	}
378
379	for (pos = 0, loop = 0; pos < total_len; pos += trans_len, loop++) {
380		trans_len = total_len - pos;
381
382		i = 0;
383		tx_only = 0;
384		list_for_each_entry(t, &m->transfers, transfer_list) {
385			if (t->tx_buf) {
386				memcpy(local_buf + i, t->tx_buf, t->len);
387				i += t->len;
388				if (!t->rx_buf)
389					tx_only += t->len;
390			}
391		}
392
393		/* Add additional TX bytes to compensate SPCOM_TRANLEN_MAX */
394		if (loop > 0)
395			trans_len += tx_only;
396
397		if (trans_len > SPCOM_TRANLEN_MAX)
398			trans_len = SPCOM_TRANLEN_MAX;
399
400		/* Update device offset */
401		if (pos > 0) {
402			addr = fsl_espi_cmd2addr(local_buf);
403			addr += rx_pos;
404			fsl_espi_addr2cmd(addr, local_buf);
405		}
406
407		espi_trans->len = trans_len;
408		espi_trans->tx_buf = local_buf;
409		espi_trans->rx_buf = local_buf;
410		fsl_espi_do_trans(m, espi_trans);
411
412		/* If there is at least one RX byte then copy it to rx_buf */
413		if (tx_only < SPCOM_TRANLEN_MAX)
414			memcpy(rx_buf + rx_pos, espi_trans->rx_buf + tx_only,
415					trans_len - tx_only);
416
417		rx_pos += trans_len - tx_only;
418
419		if (loop > 0)
420			espi_trans->actual_length += espi_trans->len - tx_only;
421		else
422			espi_trans->actual_length += espi_trans->len;
423	}
424
425	kfree(local_buf);
426}
427
428static int fsl_espi_do_one_msg(struct spi_master *master,
429			       struct spi_message *m)
430{
431	struct spi_transfer *t;
432	u8 *rx_buf = NULL;
433	unsigned int n_tx = 0;
434	unsigned int n_rx = 0;
435	unsigned int xfer_len = 0;
436	struct fsl_espi_transfer espi_trans;
437
438	list_for_each_entry(t, &m->transfers, transfer_list) {
439		if (t->tx_buf)
440			n_tx += t->len;
441		if (t->rx_buf) {
442			n_rx += t->len;
443			rx_buf = t->rx_buf;
444		}
445		if ((t->tx_buf) || (t->rx_buf))
446			xfer_len += t->len;
447	}
448
449	espi_trans.n_tx = n_tx;
450	espi_trans.n_rx = n_rx;
451	espi_trans.len = xfer_len;
452	espi_trans.actual_length = 0;
453	espi_trans.status = 0;
454
455	if (!rx_buf)
456		fsl_espi_cmd_trans(m, &espi_trans, NULL);
457	else
458		fsl_espi_rw_trans(m, &espi_trans, rx_buf);
459
460	m->actual_length = espi_trans.actual_length;
461	m->status = espi_trans.status;
462	spi_finalize_current_message(master);
463	return 0;
464}
465
466static int fsl_espi_setup(struct spi_device *spi)
467{
468	struct mpc8xxx_spi *mpc8xxx_spi;
469	struct fsl_espi_reg *reg_base;
470	int retval;
471	u32 hw_mode;
472	u32 loop_mode;
473	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
474
475	if (!spi->max_speed_hz)
476		return -EINVAL;
477
478	if (!cs) {
479		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
480		if (!cs)
481			return -ENOMEM;
482		spi_set_ctldata(spi, cs);
483	}
484
485	mpc8xxx_spi = spi_master_get_devdata(spi->master);
486	reg_base = mpc8xxx_spi->reg_base;
487
488	hw_mode = cs->hw_mode; /* Save original settings */
489	cs->hw_mode = mpc8xxx_spi_read_reg(
490			&reg_base->csmode[spi->chip_select]);
491	/* mask out bits we are going to set */
492	cs->hw_mode &= ~(CSMODE_CP_BEGIN_EDGECLK | CSMODE_CI_INACTIVEHIGH
493			 | CSMODE_REV);
494
495	if (spi->mode & SPI_CPHA)
496		cs->hw_mode |= CSMODE_CP_BEGIN_EDGECLK;
497	if (spi->mode & SPI_CPOL)
498		cs->hw_mode |= CSMODE_CI_INACTIVEHIGH;
499	if (!(spi->mode & SPI_LSB_FIRST))
500		cs->hw_mode |= CSMODE_REV;
501
502	/* Handle the loop mode */
503	loop_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
504	loop_mode &= ~SPMODE_LOOP;
505	if (spi->mode & SPI_LOOP)
506		loop_mode |= SPMODE_LOOP;
507	mpc8xxx_spi_write_reg(&reg_base->mode, loop_mode);
508
509	retval = fsl_espi_setup_transfer(spi, NULL);
510	if (retval < 0) {
511		cs->hw_mode = hw_mode; /* Restore settings */
512		return retval;
513	}
514	return 0;
515}
516
517static void fsl_espi_cleanup(struct spi_device *spi)
518{
519	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
520
521	kfree(cs);
522	spi_set_ctldata(spi, NULL);
523}
524
525void fsl_espi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
526{
527	struct fsl_espi_reg *reg_base = mspi->reg_base;
528
529	/* We need handle RX first */
530	if (events & SPIE_NE) {
531		u32 rx_data, tmp;
532		u8 rx_data_8;
533
534		/* Spin until RX is done */
535		while (SPIE_RXCNT(events) < min(4, mspi->len)) {
536			cpu_relax();
537			events = mpc8xxx_spi_read_reg(&reg_base->event);
538		}
539
540		if (mspi->len >= 4) {
541			rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
542		} else {
543			tmp = mspi->len;
544			rx_data = 0;
545			while (tmp--) {
546				rx_data_8 = in_8((u8 *)&reg_base->receive);
547				rx_data |= (rx_data_8 << (tmp * 8));
548			}
549
550			rx_data <<= (4 - mspi->len) * 8;
551		}
552
553		mspi->len -= 4;
554
555		if (mspi->rx)
556			mspi->get_rx(rx_data, mspi);
557	}
558
559	if (!(events & SPIE_NF)) {
560		int ret;
561
562		/* spin until TX is done */
563		ret = spin_event_timeout(((events = mpc8xxx_spi_read_reg(
564				&reg_base->event)) & SPIE_NF) == 0, 1000, 0);
565		if (!ret) {
566			dev_err(mspi->dev, "tired waiting for SPIE_NF\n");
567			return;
568		}
569	}
570
571	/* Clear the events */
572	mpc8xxx_spi_write_reg(&reg_base->event, events);
573
574	mspi->count -= 1;
575	if (mspi->count) {
576		u32 word = mspi->get_tx(mspi);
577
578		mpc8xxx_spi_write_reg(&reg_base->transmit, word);
579	} else {
580		complete(&mspi->done);
581	}
582}
583
584static irqreturn_t fsl_espi_irq(s32 irq, void *context_data)
585{
586	struct mpc8xxx_spi *mspi = context_data;
587	struct fsl_espi_reg *reg_base = mspi->reg_base;
588	irqreturn_t ret = IRQ_NONE;
589	u32 events;
590
591	/* Get interrupt events(tx/rx) */
592	events = mpc8xxx_spi_read_reg(&reg_base->event);
593	if (events)
594		ret = IRQ_HANDLED;
595
596	dev_vdbg(mspi->dev, "%s: events %x\n", __func__, events);
597
598	fsl_espi_cpu_irq(mspi, events);
599
600	return ret;
601}
602
603static void fsl_espi_remove(struct mpc8xxx_spi *mspi)
604{
605	iounmap(mspi->reg_base);
606}
607
608static int fsl_espi_suspend(struct spi_master *master)
609{
610	struct mpc8xxx_spi *mpc8xxx_spi;
611	struct fsl_espi_reg *reg_base;
612	u32 regval;
613
614	mpc8xxx_spi = spi_master_get_devdata(master);
615	reg_base = mpc8xxx_spi->reg_base;
616
617	regval = mpc8xxx_spi_read_reg(&reg_base->mode);
618	regval &= ~SPMODE_ENABLE;
619	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
620
621	return 0;
622}
623
624static int fsl_espi_resume(struct spi_master *master)
625{
626	struct mpc8xxx_spi *mpc8xxx_spi;
627	struct fsl_espi_reg *reg_base;
628	u32 regval;
629
630	mpc8xxx_spi = spi_master_get_devdata(master);
631	reg_base = mpc8xxx_spi->reg_base;
632
633	regval = mpc8xxx_spi_read_reg(&reg_base->mode);
634	regval |= SPMODE_ENABLE;
635	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
636
637	return 0;
638}
639
640static struct spi_master * fsl_espi_probe(struct device *dev,
641		struct resource *mem, unsigned int irq)
642{
643	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
644	struct spi_master *master;
645	struct mpc8xxx_spi *mpc8xxx_spi;
646	struct fsl_espi_reg *reg_base;
647	struct device_node *nc;
648	const __be32 *prop;
649	u32 regval, csmode;
650	int i, len, ret = 0;
651
652	master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
653	if (!master) {
654		ret = -ENOMEM;
655		goto err;
656	}
657
658	dev_set_drvdata(dev, master);
659
660	mpc8xxx_spi_probe(dev, mem, irq);
661
662	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
663	master->setup = fsl_espi_setup;
664	master->cleanup = fsl_espi_cleanup;
665	master->transfer_one_message = fsl_espi_do_one_msg;
666	master->prepare_transfer_hardware = fsl_espi_resume;
667	master->unprepare_transfer_hardware = fsl_espi_suspend;
668
669	mpc8xxx_spi = spi_master_get_devdata(master);
670	mpc8xxx_spi->spi_remove = fsl_espi_remove;
671
672	mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem));
673	if (!mpc8xxx_spi->reg_base) {
674		ret = -ENOMEM;
675		goto err_probe;
676	}
677
678	reg_base = mpc8xxx_spi->reg_base;
679
680	/* Register for SPI Interrupt */
681	ret = request_irq(mpc8xxx_spi->irq, fsl_espi_irq,
682			  0, "fsl_espi", mpc8xxx_spi);
683	if (ret)
684		goto free_irq;
685
686	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
687		mpc8xxx_spi->rx_shift = 16;
688		mpc8xxx_spi->tx_shift = 24;
689	}
690
691	/* SPI controller initializations */
692	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
693	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
694	mpc8xxx_spi_write_reg(&reg_base->command, 0);
695	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
696
697	/* Init eSPI CS mode register */
698	for_each_available_child_of_node(master->dev.of_node, nc) {
699		/* get chip select */
700		prop = of_get_property(nc, "reg", &len);
701		if (!prop || len < sizeof(*prop))
702			continue;
703		i = be32_to_cpup(prop);
704		if (i < 0 || i >= pdata->max_chipselect)
705			continue;
706
707		csmode = CSMODE_INIT_VAL;
708		/* check if CSBEF is set in device tree */
709		prop = of_get_property(nc, "fsl,csbef", &len);
710		if (prop && len >= sizeof(*prop)) {
711			csmode &= ~(CSMODE_BEF(0xf));
712			csmode |= CSMODE_BEF(be32_to_cpup(prop));
713		}
714		/* check if CSAFT is set in device tree */
715		prop = of_get_property(nc, "fsl,csaft", &len);
716		if (prop && len >= sizeof(*prop)) {
717			csmode &= ~(CSMODE_AFT(0xf));
718			csmode |= CSMODE_AFT(be32_to_cpup(prop));
719		}
720		mpc8xxx_spi_write_reg(&reg_base->csmode[i], csmode);
721
722		dev_info(dev, "cs=%d, init_csmode=0x%x\n", i, csmode);
723	}
724
725	/* Enable SPI interface */
726	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
727
728	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
729
730	ret = spi_register_master(master);
731	if (ret < 0)
732		goto unreg_master;
733
734	dev_info(dev, "at 0x%p (irq = %d)\n", reg_base, mpc8xxx_spi->irq);
735
736	return master;
737
738unreg_master:
739	free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
740free_irq:
741	iounmap(mpc8xxx_spi->reg_base);
742err_probe:
743	spi_master_put(master);
744err:
745	return ERR_PTR(ret);
746}
747
748static int of_fsl_espi_get_chipselects(struct device *dev)
749{
750	struct device_node *np = dev->of_node;
751	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
752	const u32 *prop;
753	int len;
754
755	prop = of_get_property(np, "fsl,espi-num-chipselects", &len);
756	if (!prop || len < sizeof(*prop)) {
757		dev_err(dev, "No 'fsl,espi-num-chipselects' property\n");
758		return -EINVAL;
759	}
760
761	pdata->max_chipselect = *prop;
762	pdata->cs_control = NULL;
763
764	return 0;
765}
766
767static int of_fsl_espi_probe(struct platform_device *ofdev)
768{
769	struct device *dev = &ofdev->dev;
770	struct device_node *np = ofdev->dev.of_node;
771	struct spi_master *master;
772	struct resource mem;
773	unsigned int irq;
774	int ret = -ENOMEM;
775
776	ret = of_mpc8xxx_spi_probe(ofdev);
777	if (ret)
778		return ret;
779
780	ret = of_fsl_espi_get_chipselects(dev);
781	if (ret)
782		goto err;
783
784	ret = of_address_to_resource(np, 0, &mem);
785	if (ret)
786		goto err;
787
788	irq = irq_of_parse_and_map(np, 0);
789	if (!irq) {
790		ret = -EINVAL;
791		goto err;
792	}
793
794	master = fsl_espi_probe(dev, &mem, irq);
795	if (IS_ERR(master)) {
796		ret = PTR_ERR(master);
797		goto err;
798	}
799
800	return 0;
801
802err:
803	return ret;
804}
805
806static int of_fsl_espi_remove(struct platform_device *dev)
807{
808	return mpc8xxx_spi_remove(&dev->dev);
809}
810
811#ifdef CONFIG_PM_SLEEP
812static int of_fsl_espi_suspend(struct device *dev)
813{
814	struct spi_master *master = dev_get_drvdata(dev);
815	int ret;
816
817	ret = spi_master_suspend(master);
818	if (ret) {
819		dev_warn(dev, "cannot suspend master\n");
820		return ret;
821	}
822
823	return fsl_espi_suspend(master);
824}
825
826static int of_fsl_espi_resume(struct device *dev)
827{
828	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
829	struct spi_master *master = dev_get_drvdata(dev);
830	struct mpc8xxx_spi *mpc8xxx_spi;
831	struct fsl_espi_reg *reg_base;
832	u32 regval;
833	int i;
834
835	mpc8xxx_spi = spi_master_get_devdata(master);
836	reg_base = mpc8xxx_spi->reg_base;
837
838	/* SPI controller initializations */
839	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
840	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
841	mpc8xxx_spi_write_reg(&reg_base->command, 0);
842	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
843
844	/* Init eSPI CS mode register */
845	for (i = 0; i < pdata->max_chipselect; i++)
846		mpc8xxx_spi_write_reg(&reg_base->csmode[i], CSMODE_INIT_VAL);
847
848	/* Enable SPI interface */
849	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
850
851	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
852
853	return spi_master_resume(master);
854}
855#endif /* CONFIG_PM_SLEEP */
856
857static const struct dev_pm_ops espi_pm = {
858	SET_SYSTEM_SLEEP_PM_OPS(of_fsl_espi_suspend, of_fsl_espi_resume)
859};
860
861static const struct of_device_id of_fsl_espi_match[] = {
862	{ .compatible = "fsl,mpc8536-espi" },
863	{}
864};
865MODULE_DEVICE_TABLE(of, of_fsl_espi_match);
866
867static struct platform_driver fsl_espi_driver = {
868	.driver = {
869		.name = "fsl_espi",
870		.of_match_table = of_fsl_espi_match,
871		.pm = &espi_pm,
872	},
873	.probe		= of_fsl_espi_probe,
874	.remove		= of_fsl_espi_remove,
875};
876module_platform_driver(fsl_espi_driver);
877
878MODULE_AUTHOR("Mingkai Hu");
879MODULE_DESCRIPTION("Enhanced Freescale SPI Driver");
880MODULE_LICENSE("GPL");
881