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 <linux/pm_runtime.h>
25#include <sysdev/fsl_soc.h>
26
27#include "spi-fsl-lib.h"
28
29/* eSPI Controller registers */
30struct fsl_espi_reg {
31	__be32 mode;		/* 0x000 - eSPI mode register */
32	__be32 event;		/* 0x004 - eSPI event register */
33	__be32 mask;		/* 0x008 - eSPI mask register */
34	__be32 command;		/* 0x00c - eSPI command register */
35	__be32 transmit;	/* 0x010 - eSPI transmit FIFO access register*/
36	__be32 receive;		/* 0x014 - eSPI receive FIFO access register*/
37	u8 res[8];		/* 0x018 - 0x01c reserved */
38	__be32 csmode[4];	/* 0x020 - 0x02c eSPI cs mode register */
39};
40
41struct fsl_espi_transfer {
42	const void *tx_buf;
43	void *rx_buf;
44	unsigned len;
45	unsigned n_tx;
46	unsigned n_rx;
47	unsigned actual_length;
48	int status;
49};
50
51/* eSPI Controller mode register definitions */
52#define SPMODE_ENABLE		(1 << 31)
53#define SPMODE_LOOP		(1 << 30)
54#define SPMODE_TXTHR(x)		((x) << 8)
55#define SPMODE_RXTHR(x)		((x) << 0)
56
57/* eSPI Controller CS mode register definitions */
58#define CSMODE_CI_INACTIVEHIGH	(1 << 31)
59#define CSMODE_CP_BEGIN_EDGECLK	(1 << 30)
60#define CSMODE_REV		(1 << 29)
61#define CSMODE_DIV16		(1 << 28)
62#define CSMODE_PM(x)		((x) << 24)
63#define CSMODE_POL_1		(1 << 20)
64#define CSMODE_LEN(x)		((x) << 16)
65#define CSMODE_BEF(x)		((x) << 12)
66#define CSMODE_AFT(x)		((x) << 8)
67#define CSMODE_CG(x)		((x) << 3)
68
69/* Default mode/csmode for eSPI controller */
70#define SPMODE_INIT_VAL (SPMODE_TXTHR(4) | SPMODE_RXTHR(3))
71#define CSMODE_INIT_VAL (CSMODE_POL_1 | CSMODE_BEF(0) \
72		| CSMODE_AFT(0) | CSMODE_CG(1))
73
74/* SPIE register values */
75#define	SPIE_NE		0x00000200	/* Not empty */
76#define	SPIE_NF		0x00000100	/* Not full */
77
78/* SPIM register values */
79#define	SPIM_NE		0x00000200	/* Not empty */
80#define	SPIM_NF		0x00000100	/* Not full */
81#define SPIE_RXCNT(reg)     ((reg >> 24) & 0x3F)
82#define SPIE_TXCNT(reg)     ((reg >> 16) & 0x3F)
83
84/* SPCOM register values */
85#define SPCOM_CS(x)		((x) << 30)
86#define SPCOM_TRANLEN(x)	((x) << 0)
87#define	SPCOM_TRANLEN_MAX	0xFFFF	/* Max transaction length */
88
89#define AUTOSUSPEND_TIMEOUT 2000
90
91static void fsl_espi_change_mode(struct spi_device *spi)
92{
93	struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
94	struct spi_mpc8xxx_cs *cs = spi->controller_state;
95	struct fsl_espi_reg *reg_base = mspi->reg_base;
96	__be32 __iomem *mode = &reg_base->csmode[spi->chip_select];
97	__be32 __iomem *espi_mode = &reg_base->mode;
98	u32 tmp;
99	unsigned long flags;
100
101	/* Turn off IRQs locally to minimize time that SPI is disabled. */
102	local_irq_save(flags);
103
104	/* Turn off SPI unit prior changing mode */
105	tmp = mpc8xxx_spi_read_reg(espi_mode);
106	mpc8xxx_spi_write_reg(espi_mode, tmp & ~SPMODE_ENABLE);
107	mpc8xxx_spi_write_reg(mode, cs->hw_mode);
108	mpc8xxx_spi_write_reg(espi_mode, tmp);
109
110	local_irq_restore(flags);
111}
112
113static u32 fsl_espi_tx_buf_lsb(struct mpc8xxx_spi *mpc8xxx_spi)
114{
115	u32 data;
116	u16 data_h;
117	u16 data_l;
118	const u32 *tx = mpc8xxx_spi->tx;
119
120	if (!tx)
121		return 0;
122
123	data = *tx++ << mpc8xxx_spi->tx_shift;
124	data_l = data & 0xffff;
125	data_h = (data >> 16) & 0xffff;
126	swab16s(&data_l);
127	swab16s(&data_h);
128	data = data_h | data_l;
129
130	mpc8xxx_spi->tx = tx;
131	return data;
132}
133
134static int fsl_espi_setup_transfer(struct spi_device *spi,
135					struct spi_transfer *t)
136{
137	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
138	int bits_per_word = 0;
139	u8 pm;
140	u32 hz = 0;
141	struct spi_mpc8xxx_cs *cs = spi->controller_state;
142
143	if (t) {
144		bits_per_word = t->bits_per_word;
145		hz = t->speed_hz;
146	}
147
148	/* spi_transfer level calls that work per-word */
149	if (!bits_per_word)
150		bits_per_word = spi->bits_per_word;
151
152	if (!hz)
153		hz = spi->max_speed_hz;
154
155	cs->rx_shift = 0;
156	cs->tx_shift = 0;
157	cs->get_rx = mpc8xxx_spi_rx_buf_u32;
158	cs->get_tx = mpc8xxx_spi_tx_buf_u32;
159	if (bits_per_word <= 8) {
160		cs->rx_shift = 8 - bits_per_word;
161	} else {
162		cs->rx_shift = 16 - bits_per_word;
163		if (spi->mode & SPI_LSB_FIRST)
164			cs->get_tx = fsl_espi_tx_buf_lsb;
165	}
166
167	mpc8xxx_spi->rx_shift = cs->rx_shift;
168	mpc8xxx_spi->tx_shift = cs->tx_shift;
169	mpc8xxx_spi->get_rx = cs->get_rx;
170	mpc8xxx_spi->get_tx = cs->get_tx;
171
172	bits_per_word = bits_per_word - 1;
173
174	/* mask out bits we are going to set */
175	cs->hw_mode &= ~(CSMODE_LEN(0xF) | CSMODE_DIV16 | CSMODE_PM(0xF));
176
177	cs->hw_mode |= CSMODE_LEN(bits_per_word);
178
179	if ((mpc8xxx_spi->spibrg / hz) > 64) {
180		cs->hw_mode |= CSMODE_DIV16;
181		pm = DIV_ROUND_UP(mpc8xxx_spi->spibrg, hz * 16 * 4);
182
183		WARN_ONCE(pm > 33, "%s: Requested speed is too low: %d Hz. "
184			  "Will use %d Hz instead.\n", dev_name(&spi->dev),
185				hz, mpc8xxx_spi->spibrg / (4 * 16 * (32 + 1)));
186		if (pm > 33)
187			pm = 33;
188	} else {
189		pm = DIV_ROUND_UP(mpc8xxx_spi->spibrg, hz * 4);
190	}
191	if (pm)
192		pm--;
193	if (pm < 2)
194		pm = 2;
195
196	cs->hw_mode |= CSMODE_PM(pm);
197
198	fsl_espi_change_mode(spi);
199	return 0;
200}
201
202static int fsl_espi_cpu_bufs(struct mpc8xxx_spi *mspi, struct spi_transfer *t,
203		unsigned int len)
204{
205	u32 word;
206	struct fsl_espi_reg *reg_base = mspi->reg_base;
207
208	mspi->count = len;
209
210	/* enable rx ints */
211	mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
212
213	/* transmit word */
214	word = mspi->get_tx(mspi);
215	mpc8xxx_spi_write_reg(&reg_base->transmit, word);
216
217	return 0;
218}
219
220static int fsl_espi_bufs(struct spi_device *spi, struct spi_transfer *t)
221{
222	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
223	struct fsl_espi_reg *reg_base = mpc8xxx_spi->reg_base;
224	unsigned int len = t->len;
225	int ret;
226
227	mpc8xxx_spi->len = t->len;
228	len = roundup(len, 4) / 4;
229
230	mpc8xxx_spi->tx = t->tx_buf;
231	mpc8xxx_spi->rx = t->rx_buf;
232
233	reinit_completion(&mpc8xxx_spi->done);
234
235	/* Set SPCOM[CS] and SPCOM[TRANLEN] field */
236	if ((t->len - 1) > SPCOM_TRANLEN_MAX) {
237		dev_err(mpc8xxx_spi->dev, "Transaction length (%d)"
238				" beyond the SPCOM[TRANLEN] field\n", t->len);
239		return -EINVAL;
240	}
241	mpc8xxx_spi_write_reg(&reg_base->command,
242		(SPCOM_CS(spi->chip_select) | SPCOM_TRANLEN(t->len - 1)));
243
244	ret = fsl_espi_cpu_bufs(mpc8xxx_spi, t, len);
245	if (ret)
246		return ret;
247
248	wait_for_completion(&mpc8xxx_spi->done);
249
250	/* disable rx ints */
251	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
252
253	return mpc8xxx_spi->count;
254}
255
256static inline void fsl_espi_addr2cmd(unsigned int addr, u8 *cmd)
257{
258	if (cmd) {
259		cmd[1] = (u8)(addr >> 16);
260		cmd[2] = (u8)(addr >> 8);
261		cmd[3] = (u8)(addr >> 0);
262	}
263}
264
265static inline unsigned int fsl_espi_cmd2addr(u8 *cmd)
266{
267	if (cmd)
268		return cmd[1] << 16 | cmd[2] << 8 | cmd[3] << 0;
269
270	return 0;
271}
272
273static void fsl_espi_do_trans(struct spi_message *m,
274				struct fsl_espi_transfer *tr)
275{
276	struct spi_device *spi = m->spi;
277	struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
278	struct fsl_espi_transfer *espi_trans = tr;
279	struct spi_message message;
280	struct spi_transfer *t, *first, trans;
281	int status = 0;
282
283	spi_message_init(&message);
284	memset(&trans, 0, sizeof(trans));
285
286	first = list_first_entry(&m->transfers, struct spi_transfer,
287			transfer_list);
288	list_for_each_entry(t, &m->transfers, transfer_list) {
289		if ((first->bits_per_word != t->bits_per_word) ||
290			(first->speed_hz != t->speed_hz)) {
291			espi_trans->status = -EINVAL;
292			dev_err(mspi->dev,
293				"bits_per_word/speed_hz should be same for the same SPI transfer\n");
294			return;
295		}
296
297		trans.speed_hz = t->speed_hz;
298		trans.bits_per_word = t->bits_per_word;
299		trans.delay_usecs = max(first->delay_usecs, t->delay_usecs);
300	}
301
302	trans.len = espi_trans->len;
303	trans.tx_buf = espi_trans->tx_buf;
304	trans.rx_buf = espi_trans->rx_buf;
305	spi_message_add_tail(&trans, &message);
306
307	list_for_each_entry(t, &message.transfers, transfer_list) {
308		if (t->bits_per_word || t->speed_hz) {
309			status = -EINVAL;
310
311			status = fsl_espi_setup_transfer(spi, t);
312			if (status < 0)
313				break;
314		}
315
316		if (t->len)
317			status = fsl_espi_bufs(spi, t);
318
319		if (status) {
320			status = -EMSGSIZE;
321			break;
322		}
323
324		if (t->delay_usecs)
325			udelay(t->delay_usecs);
326	}
327
328	espi_trans->status = status;
329	fsl_espi_setup_transfer(spi, NULL);
330}
331
332static void fsl_espi_cmd_trans(struct spi_message *m,
333				struct fsl_espi_transfer *trans, u8 *rx_buff)
334{
335	struct spi_transfer *t;
336	u8 *local_buf;
337	int i = 0;
338	struct fsl_espi_transfer *espi_trans = trans;
339
340	local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
341	if (!local_buf) {
342		espi_trans->status = -ENOMEM;
343		return;
344	}
345
346	list_for_each_entry(t, &m->transfers, transfer_list) {
347		if (t->tx_buf) {
348			memcpy(local_buf + i, t->tx_buf, t->len);
349			i += t->len;
350		}
351	}
352
353	espi_trans->tx_buf = local_buf;
354	espi_trans->rx_buf = local_buf;
355	fsl_espi_do_trans(m, espi_trans);
356
357	espi_trans->actual_length = espi_trans->len;
358	kfree(local_buf);
359}
360
361static void fsl_espi_rw_trans(struct spi_message *m,
362				struct fsl_espi_transfer *trans, u8 *rx_buff)
363{
364	struct fsl_espi_transfer *espi_trans = trans;
365	unsigned int total_len = espi_trans->len;
366	struct spi_transfer *t;
367	u8 *local_buf;
368	u8 *rx_buf = rx_buff;
369	unsigned int trans_len;
370	unsigned int addr;
371	unsigned int tx_only;
372	unsigned int rx_pos = 0;
373	unsigned int pos;
374	int i, loop;
375
376	local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
377	if (!local_buf) {
378		espi_trans->status = -ENOMEM;
379		return;
380	}
381
382	for (pos = 0, loop = 0; pos < total_len; pos += trans_len, loop++) {
383		trans_len = total_len - pos;
384
385		i = 0;
386		tx_only = 0;
387		list_for_each_entry(t, &m->transfers, transfer_list) {
388			if (t->tx_buf) {
389				memcpy(local_buf + i, t->tx_buf, t->len);
390				i += t->len;
391				if (!t->rx_buf)
392					tx_only += t->len;
393			}
394		}
395
396		/* Add additional TX bytes to compensate SPCOM_TRANLEN_MAX */
397		if (loop > 0)
398			trans_len += tx_only;
399
400		if (trans_len > SPCOM_TRANLEN_MAX)
401			trans_len = SPCOM_TRANLEN_MAX;
402
403		/* Update device offset */
404		if (pos > 0) {
405			addr = fsl_espi_cmd2addr(local_buf);
406			addr += rx_pos;
407			fsl_espi_addr2cmd(addr, local_buf);
408		}
409
410		espi_trans->len = trans_len;
411		espi_trans->tx_buf = local_buf;
412		espi_trans->rx_buf = local_buf;
413		fsl_espi_do_trans(m, espi_trans);
414
415		/* If there is at least one RX byte then copy it to rx_buf */
416		if (tx_only < SPCOM_TRANLEN_MAX)
417			memcpy(rx_buf + rx_pos, espi_trans->rx_buf + tx_only,
418					trans_len - tx_only);
419
420		rx_pos += trans_len - tx_only;
421
422		if (loop > 0)
423			espi_trans->actual_length += espi_trans->len - tx_only;
424		else
425			espi_trans->actual_length += espi_trans->len;
426	}
427
428	kfree(local_buf);
429}
430
431static int fsl_espi_do_one_msg(struct spi_master *master,
432			       struct spi_message *m)
433{
434	struct spi_transfer *t;
435	u8 *rx_buf = NULL;
436	unsigned int n_tx = 0;
437	unsigned int n_rx = 0;
438	unsigned int xfer_len = 0;
439	struct fsl_espi_transfer espi_trans;
440
441	list_for_each_entry(t, &m->transfers, transfer_list) {
442		if (t->tx_buf)
443			n_tx += t->len;
444		if (t->rx_buf) {
445			n_rx += t->len;
446			rx_buf = t->rx_buf;
447		}
448		if ((t->tx_buf) || (t->rx_buf))
449			xfer_len += t->len;
450	}
451
452	espi_trans.n_tx = n_tx;
453	espi_trans.n_rx = n_rx;
454	espi_trans.len = xfer_len;
455	espi_trans.actual_length = 0;
456	espi_trans.status = 0;
457
458	if (!rx_buf)
459		fsl_espi_cmd_trans(m, &espi_trans, NULL);
460	else
461		fsl_espi_rw_trans(m, &espi_trans, rx_buf);
462
463	m->actual_length = espi_trans.actual_length;
464	m->status = espi_trans.status;
465	spi_finalize_current_message(master);
466	return 0;
467}
468
469static int fsl_espi_setup(struct spi_device *spi)
470{
471	struct mpc8xxx_spi *mpc8xxx_spi;
472	struct fsl_espi_reg *reg_base;
473	int retval;
474	u32 hw_mode;
475	u32 loop_mode;
476	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
477
478	if (!spi->max_speed_hz)
479		return -EINVAL;
480
481	if (!cs) {
482		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
483		if (!cs)
484			return -ENOMEM;
485		spi_set_ctldata(spi, cs);
486	}
487
488	mpc8xxx_spi = spi_master_get_devdata(spi->master);
489	reg_base = mpc8xxx_spi->reg_base;
490
491	pm_runtime_get_sync(mpc8xxx_spi->dev);
492
493	hw_mode = cs->hw_mode; /* Save original settings */
494	cs->hw_mode = mpc8xxx_spi_read_reg(
495			&reg_base->csmode[spi->chip_select]);
496	/* mask out bits we are going to set */
497	cs->hw_mode &= ~(CSMODE_CP_BEGIN_EDGECLK | CSMODE_CI_INACTIVEHIGH
498			 | CSMODE_REV);
499
500	if (spi->mode & SPI_CPHA)
501		cs->hw_mode |= CSMODE_CP_BEGIN_EDGECLK;
502	if (spi->mode & SPI_CPOL)
503		cs->hw_mode |= CSMODE_CI_INACTIVEHIGH;
504	if (!(spi->mode & SPI_LSB_FIRST))
505		cs->hw_mode |= CSMODE_REV;
506
507	/* Handle the loop mode */
508	loop_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
509	loop_mode &= ~SPMODE_LOOP;
510	if (spi->mode & SPI_LOOP)
511		loop_mode |= SPMODE_LOOP;
512	mpc8xxx_spi_write_reg(&reg_base->mode, loop_mode);
513
514	retval = fsl_espi_setup_transfer(spi, NULL);
515
516	pm_runtime_mark_last_busy(mpc8xxx_spi->dev);
517	pm_runtime_put_autosuspend(mpc8xxx_spi->dev);
518
519	if (retval < 0) {
520		cs->hw_mode = hw_mode; /* Restore settings */
521		return retval;
522	}
523	return 0;
524}
525
526static void fsl_espi_cleanup(struct spi_device *spi)
527{
528	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
529
530	kfree(cs);
531	spi_set_ctldata(spi, NULL);
532}
533
534void fsl_espi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
535{
536	struct fsl_espi_reg *reg_base = mspi->reg_base;
537
538	/* We need handle RX first */
539	if (events & SPIE_NE) {
540		u32 rx_data, tmp;
541		u8 rx_data_8;
542
543		/* Spin until RX is done */
544		while (SPIE_RXCNT(events) < min(4, mspi->len)) {
545			cpu_relax();
546			events = mpc8xxx_spi_read_reg(&reg_base->event);
547		}
548
549		if (mspi->len >= 4) {
550			rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
551		} else {
552			tmp = mspi->len;
553			rx_data = 0;
554			while (tmp--) {
555				rx_data_8 = in_8((u8 *)&reg_base->receive);
556				rx_data |= (rx_data_8 << (tmp * 8));
557			}
558
559			rx_data <<= (4 - mspi->len) * 8;
560		}
561
562		mspi->len -= 4;
563
564		if (mspi->rx)
565			mspi->get_rx(rx_data, mspi);
566	}
567
568	if (!(events & SPIE_NF)) {
569		int ret;
570
571		/* spin until TX is done */
572		ret = spin_event_timeout(((events = mpc8xxx_spi_read_reg(
573				&reg_base->event)) & SPIE_NF), 1000, 0);
574		if (!ret) {
575			dev_err(mspi->dev, "tired waiting for SPIE_NF\n");
576
577			/* Clear the SPIE bits */
578			mpc8xxx_spi_write_reg(&reg_base->event, events);
579			complete(&mspi->done);
580			return;
581		}
582	}
583
584	/* Clear the events */
585	mpc8xxx_spi_write_reg(&reg_base->event, events);
586
587	mspi->count -= 1;
588	if (mspi->count) {
589		u32 word = mspi->get_tx(mspi);
590
591		mpc8xxx_spi_write_reg(&reg_base->transmit, word);
592	} else {
593		complete(&mspi->done);
594	}
595}
596
597static irqreturn_t fsl_espi_irq(s32 irq, void *context_data)
598{
599	struct mpc8xxx_spi *mspi = context_data;
600	struct fsl_espi_reg *reg_base = mspi->reg_base;
601	irqreturn_t ret = IRQ_NONE;
602	u32 events;
603
604	/* Get interrupt events(tx/rx) */
605	events = mpc8xxx_spi_read_reg(&reg_base->event);
606	if (events)
607		ret = IRQ_HANDLED;
608
609	dev_vdbg(mspi->dev, "%s: events %x\n", __func__, events);
610
611	fsl_espi_cpu_irq(mspi, events);
612
613	return ret;
614}
615
616#ifdef CONFIG_PM
617static int fsl_espi_runtime_suspend(struct device *dev)
618{
619	struct spi_master *master = dev_get_drvdata(dev);
620	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
621	struct fsl_espi_reg *reg_base = mpc8xxx_spi->reg_base;
622	u32 regval;
623
624	regval = mpc8xxx_spi_read_reg(&reg_base->mode);
625	regval &= ~SPMODE_ENABLE;
626	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
627
628	return 0;
629}
630
631static int fsl_espi_runtime_resume(struct device *dev)
632{
633	struct spi_master *master = dev_get_drvdata(dev);
634	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
635	struct fsl_espi_reg *reg_base = mpc8xxx_spi->reg_base;
636	u32 regval;
637
638	regval = mpc8xxx_spi_read_reg(&reg_base->mode);
639	regval |= SPMODE_ENABLE;
640	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
641
642	return 0;
643}
644#endif
645
646static struct spi_master * fsl_espi_probe(struct device *dev,
647		struct resource *mem, unsigned int irq)
648{
649	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
650	struct spi_master *master;
651	struct mpc8xxx_spi *mpc8xxx_spi;
652	struct fsl_espi_reg *reg_base;
653	struct device_node *nc;
654	const __be32 *prop;
655	u32 regval, csmode;
656	int i, len, ret = 0;
657
658	master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
659	if (!master) {
660		ret = -ENOMEM;
661		goto err;
662	}
663
664	dev_set_drvdata(dev, master);
665
666	mpc8xxx_spi_probe(dev, mem, irq);
667
668	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
669	master->setup = fsl_espi_setup;
670	master->cleanup = fsl_espi_cleanup;
671	master->transfer_one_message = fsl_espi_do_one_msg;
672	master->auto_runtime_pm = true;
673
674	mpc8xxx_spi = spi_master_get_devdata(master);
675
676	mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem);
677	if (IS_ERR(mpc8xxx_spi->reg_base)) {
678		ret = PTR_ERR(mpc8xxx_spi->reg_base);
679		goto err_probe;
680	}
681
682	reg_base = mpc8xxx_spi->reg_base;
683
684	/* Register for SPI Interrupt */
685	ret = devm_request_irq(dev, mpc8xxx_spi->irq, fsl_espi_irq,
686			  0, "fsl_espi", mpc8xxx_spi);
687	if (ret)
688		goto err_probe;
689
690	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
691		mpc8xxx_spi->rx_shift = 16;
692		mpc8xxx_spi->tx_shift = 24;
693	}
694
695	/* SPI controller initializations */
696	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
697	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
698	mpc8xxx_spi_write_reg(&reg_base->command, 0);
699	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
700
701	/* Init eSPI CS mode register */
702	for_each_available_child_of_node(master->dev.of_node, nc) {
703		/* get chip select */
704		prop = of_get_property(nc, "reg", &len);
705		if (!prop || len < sizeof(*prop))
706			continue;
707		i = be32_to_cpup(prop);
708		if (i < 0 || i >= pdata->max_chipselect)
709			continue;
710
711		csmode = CSMODE_INIT_VAL;
712		/* check if CSBEF is set in device tree */
713		prop = of_get_property(nc, "fsl,csbef", &len);
714		if (prop && len >= sizeof(*prop)) {
715			csmode &= ~(CSMODE_BEF(0xf));
716			csmode |= CSMODE_BEF(be32_to_cpup(prop));
717		}
718		/* check if CSAFT is set in device tree */
719		prop = of_get_property(nc, "fsl,csaft", &len);
720		if (prop && len >= sizeof(*prop)) {
721			csmode &= ~(CSMODE_AFT(0xf));
722			csmode |= CSMODE_AFT(be32_to_cpup(prop));
723		}
724		mpc8xxx_spi_write_reg(&reg_base->csmode[i], csmode);
725
726		dev_info(dev, "cs=%d, init_csmode=0x%x\n", i, csmode);
727	}
728
729	/* Enable SPI interface */
730	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
731
732	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
733
734	pm_runtime_set_autosuspend_delay(dev, AUTOSUSPEND_TIMEOUT);
735	pm_runtime_use_autosuspend(dev);
736	pm_runtime_set_active(dev);
737	pm_runtime_enable(dev);
738	pm_runtime_get_sync(dev);
739
740	ret = devm_spi_register_master(dev, master);
741	if (ret < 0)
742		goto err_pm;
743
744	dev_info(dev, "at 0x%p (irq = %d)\n", reg_base, mpc8xxx_spi->irq);
745
746	pm_runtime_mark_last_busy(dev);
747	pm_runtime_put_autosuspend(dev);
748
749	return master;
750
751err_pm:
752	pm_runtime_put_noidle(dev);
753	pm_runtime_disable(dev);
754	pm_runtime_set_suspended(dev);
755err_probe:
756	spi_master_put(master);
757err:
758	return ERR_PTR(ret);
759}
760
761static int of_fsl_espi_get_chipselects(struct device *dev)
762{
763	struct device_node *np = dev->of_node;
764	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
765	const u32 *prop;
766	int len;
767
768	prop = of_get_property(np, "fsl,espi-num-chipselects", &len);
769	if (!prop || len < sizeof(*prop)) {
770		dev_err(dev, "No 'fsl,espi-num-chipselects' property\n");
771		return -EINVAL;
772	}
773
774	pdata->max_chipselect = *prop;
775	pdata->cs_control = NULL;
776
777	return 0;
778}
779
780static int of_fsl_espi_probe(struct platform_device *ofdev)
781{
782	struct device *dev = &ofdev->dev;
783	struct device_node *np = ofdev->dev.of_node;
784	struct spi_master *master;
785	struct resource mem;
786	unsigned int irq;
787	int ret = -ENOMEM;
788
789	ret = of_mpc8xxx_spi_probe(ofdev);
790	if (ret)
791		return ret;
792
793	ret = of_fsl_espi_get_chipselects(dev);
794	if (ret)
795		goto err;
796
797	ret = of_address_to_resource(np, 0, &mem);
798	if (ret)
799		goto err;
800
801	irq = irq_of_parse_and_map(np, 0);
802	if (!irq) {
803		ret = -EINVAL;
804		goto err;
805	}
806
807	master = fsl_espi_probe(dev, &mem, irq);
808	if (IS_ERR(master)) {
809		ret = PTR_ERR(master);
810		goto err;
811	}
812
813	return 0;
814
815err:
816	return ret;
817}
818
819static int of_fsl_espi_remove(struct platform_device *dev)
820{
821	pm_runtime_disable(&dev->dev);
822
823	return 0;
824}
825
826#ifdef CONFIG_PM_SLEEP
827static int of_fsl_espi_suspend(struct device *dev)
828{
829	struct spi_master *master = dev_get_drvdata(dev);
830	int ret;
831
832	ret = spi_master_suspend(master);
833	if (ret) {
834		dev_warn(dev, "cannot suspend master\n");
835		return ret;
836	}
837
838	ret = pm_runtime_force_suspend(dev);
839	if (ret < 0)
840		return ret;
841
842	return 0;
843}
844
845static int of_fsl_espi_resume(struct device *dev)
846{
847	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
848	struct spi_master *master = dev_get_drvdata(dev);
849	struct mpc8xxx_spi *mpc8xxx_spi;
850	struct fsl_espi_reg *reg_base;
851	u32 regval;
852	int i, ret;
853
854	mpc8xxx_spi = spi_master_get_devdata(master);
855	reg_base = mpc8xxx_spi->reg_base;
856
857	/* SPI controller initializations */
858	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
859	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
860	mpc8xxx_spi_write_reg(&reg_base->command, 0);
861	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
862
863	/* Init eSPI CS mode register */
864	for (i = 0; i < pdata->max_chipselect; i++)
865		mpc8xxx_spi_write_reg(&reg_base->csmode[i], CSMODE_INIT_VAL);
866
867	/* Enable SPI interface */
868	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
869
870	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
871
872	ret = pm_runtime_force_resume(dev);
873	if (ret < 0)
874		return ret;
875
876	return spi_master_resume(master);
877}
878#endif /* CONFIG_PM_SLEEP */
879
880static const struct dev_pm_ops espi_pm = {
881	SET_RUNTIME_PM_OPS(fsl_espi_runtime_suspend,
882			   fsl_espi_runtime_resume, NULL)
883	SET_SYSTEM_SLEEP_PM_OPS(of_fsl_espi_suspend, of_fsl_espi_resume)
884};
885
886static const struct of_device_id of_fsl_espi_match[] = {
887	{ .compatible = "fsl,mpc8536-espi" },
888	{}
889};
890MODULE_DEVICE_TABLE(of, of_fsl_espi_match);
891
892static struct platform_driver fsl_espi_driver = {
893	.driver = {
894		.name = "fsl_espi",
895		.of_match_table = of_fsl_espi_match,
896		.pm = &espi_pm,
897	},
898	.probe		= of_fsl_espi_probe,
899	.remove		= of_fsl_espi_remove,
900};
901module_platform_driver(fsl_espi_driver);
902
903MODULE_AUTHOR("Mingkai Hu");
904MODULE_DESCRIPTION("Enhanced Freescale SPI Driver");
905MODULE_LICENSE("GPL");
906