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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/module.h>
12#include <linux/delay.h>
13#include <linux/irq.h>
14#include <linux/spi/spi.h>
15#include <linux/platform_device.h>
16#include <linux/fsl_devices.h>
17#include <linux/mm.h>
18#include <linux/of.h>
19#include <linux/of_platform.h>
20#include <linux/of_spi.h>
21#include <linux/interrupt.h>
22#include <linux/err.h>
23#include <sysdev/fsl_soc.h>
24
25#include "spi-fsl-lib.h"
26
27/* eSPI Controller registers */
28struct fsl_espi_reg {
29 __be32 mode; /* 0x000 - eSPI mode register */
30 __be32 event; /* 0x004 - eSPI event register */
31 __be32 mask; /* 0x008 - eSPI mask register */
32 __be32 command; /* 0x00c - eSPI command register */
33 __be32 transmit; /* 0x010 - eSPI transmit FIFO access register*/
34 __be32 receive; /* 0x014 - eSPI receive FIFO access register*/
35 u8 res[8]; /* 0x018 - 0x01c reserved */
36 __be32 csmode[4]; /* 0x020 - 0x02c eSPI cs mode register */
37};
38
39struct fsl_espi_transfer {
40 const void *tx_buf;
41 void *rx_buf;
42 unsigned len;
43 unsigned n_tx;
44 unsigned n_rx;
45 unsigned actual_length;
46 int status;
47};
48
49/* eSPI Controller mode register definitions */
50#define SPMODE_ENABLE (1 << 31)
51#define SPMODE_LOOP (1 << 30)
52#define SPMODE_TXTHR(x) ((x) << 8)
53#define SPMODE_RXTHR(x) ((x) << 0)
54
55/* eSPI Controller CS mode register definitions */
56#define CSMODE_CI_INACTIVEHIGH (1 << 31)
57#define CSMODE_CP_BEGIN_EDGECLK (1 << 30)
58#define CSMODE_REV (1 << 29)
59#define CSMODE_DIV16 (1 << 28)
60#define CSMODE_PM(x) ((x) << 24)
61#define CSMODE_POL_1 (1 << 20)
62#define CSMODE_LEN(x) ((x) << 16)
63#define CSMODE_BEF(x) ((x) << 12)
64#define CSMODE_AFT(x) ((x) << 8)
65#define CSMODE_CG(x) ((x) << 3)
66
67/* Default mode/csmode for eSPI controller */
68#define SPMODE_INIT_VAL (SPMODE_TXTHR(4) | SPMODE_RXTHR(3))
69#define CSMODE_INIT_VAL (CSMODE_POL_1 | CSMODE_BEF(0) \
70 | CSMODE_AFT(0) | CSMODE_CG(1))
71
72/* SPIE register values */
73#define SPIE_NE 0x00000200 /* Not empty */
74#define SPIE_NF 0x00000100 /* Not full */
75
76/* SPIM register values */
77#define SPIM_NE 0x00000200 /* Not empty */
78#define SPIM_NF 0x00000100 /* Not full */
79#define SPIE_RXCNT(reg) ((reg >> 24) & 0x3F)
80#define SPIE_TXCNT(reg) ((reg >> 16) & 0x3F)
81
82/* SPCOM register values */
83#define SPCOM_CS(x) ((x) << 30)
84#define SPCOM_TRANLEN(x) ((x) << 0)
85#define SPCOM_TRANLEN_MAX 0xFFFF /* Max transaction length */
86
87static void fsl_espi_change_mode(struct spi_device *spi)
88{
89 struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
90 struct spi_mpc8xxx_cs *cs = spi->controller_state;
91 struct fsl_espi_reg *reg_base = mspi->reg_base;
92 __be32 __iomem *mode = ®_base->csmode[spi->chip_select];
93 __be32 __iomem *espi_mode = ®_base->mode;
94 u32 tmp;
95 unsigned long flags;
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 tmp = mpc8xxx_spi_read_reg(espi_mode);
102 mpc8xxx_spi_write_reg(espi_mode, tmp & ~SPMODE_ENABLE);
103 mpc8xxx_spi_write_reg(mode, cs->hw_mode);
104 mpc8xxx_spi_write_reg(espi_mode, tmp);
105
106 local_irq_restore(flags);
107}
108
109static u32 fsl_espi_tx_buf_lsb(struct mpc8xxx_spi *mpc8xxx_spi)
110{
111 u32 data;
112 u16 data_h;
113 u16 data_l;
114 const u32 *tx = mpc8xxx_spi->tx;
115
116 if (!tx)
117 return 0;
118
119 data = *tx++ << mpc8xxx_spi->tx_shift;
120 data_l = data & 0xffff;
121 data_h = (data >> 16) & 0xffff;
122 swab16s(&data_l);
123 swab16s(&data_h);
124 data = data_h | data_l;
125
126 mpc8xxx_spi->tx = tx;
127 return data;
128}
129
130static int fsl_espi_setup_transfer(struct spi_device *spi,
131 struct spi_transfer *t)
132{
133 struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
134 int bits_per_word = 0;
135 u8 pm;
136 u32 hz = 0;
137 struct spi_mpc8xxx_cs *cs = spi->controller_state;
138
139 if (t) {
140 bits_per_word = t->bits_per_word;
141 hz = t->speed_hz;
142 }
143
144 /* spi_transfer level calls that work per-word */
145 if (!bits_per_word)
146 bits_per_word = spi->bits_per_word;
147
148 /* Make sure its a bit width we support [4..16] */
149 if ((bits_per_word < 4) || (bits_per_word > 16))
150 return -EINVAL;
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 if (bits_per_word <= 16) {
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 } else {
166 return -EINVAL;
167 }
168
169 mpc8xxx_spi->rx_shift = cs->rx_shift;
170 mpc8xxx_spi->tx_shift = cs->tx_shift;
171 mpc8xxx_spi->get_rx = cs->get_rx;
172 mpc8xxx_spi->get_tx = cs->get_tx;
173
174 bits_per_word = bits_per_word - 1;
175
176 /* mask out bits we are going to set */
177 cs->hw_mode &= ~(CSMODE_LEN(0xF) | CSMODE_DIV16 | CSMODE_PM(0xF));
178
179 cs->hw_mode |= CSMODE_LEN(bits_per_word);
180
181 if ((mpc8xxx_spi->spibrg / hz) > 64) {
182 cs->hw_mode |= CSMODE_DIV16;
183 pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
184
185 WARN_ONCE(pm > 16, "%s: Requested speed is too low: %d Hz. "
186 "Will use %d Hz instead.\n", dev_name(&spi->dev),
187 hz, mpc8xxx_spi->spibrg / 1024);
188 if (pm > 16)
189 pm = 16;
190 } else {
191 pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
192 }
193 if (pm)
194 pm--;
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(®_base->mask, SPIM_NE);
212
213 /* transmit word */
214 word = mspi->get_tx(mspi);
215 mpc8xxx_spi_write_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 u8 bits_per_word;
226 int ret;
227
228 bits_per_word = spi->bits_per_word;
229 if (t->bits_per_word)
230 bits_per_word = t->bits_per_word;
231
232 mpc8xxx_spi->len = t->len;
233 len = roundup(len, 4) / 4;
234
235 mpc8xxx_spi->tx = t->tx_buf;
236 mpc8xxx_spi->rx = t->rx_buf;
237
238 INIT_COMPLETION(mpc8xxx_spi->done);
239
240 /* Set SPCOM[CS] and SPCOM[TRANLEN] field */
241 if ((t->len - 1) > SPCOM_TRANLEN_MAX) {
242 dev_err(mpc8xxx_spi->dev, "Transaction length (%d)"
243 " beyond the SPCOM[TRANLEN] field\n", t->len);
244 return -EINVAL;
245 }
246 mpc8xxx_spi_write_reg(®_base->command,
247 (SPCOM_CS(spi->chip_select) | SPCOM_TRANLEN(t->len - 1)));
248
249 ret = fsl_espi_cpu_bufs(mpc8xxx_spi, t, len);
250 if (ret)
251 return ret;
252
253 wait_for_completion(&mpc8xxx_spi->done);
254
255 /* disable rx ints */
256 mpc8xxx_spi_write_reg(®_base->mask, 0);
257
258 return mpc8xxx_spi->count;
259}
260
261static inline void fsl_espi_addr2cmd(unsigned int addr, u8 *cmd)
262{
263 if (cmd) {
264 cmd[1] = (u8)(addr >> 16);
265 cmd[2] = (u8)(addr >> 8);
266 cmd[3] = (u8)(addr >> 0);
267 }
268}
269
270static inline unsigned int fsl_espi_cmd2addr(u8 *cmd)
271{
272 if (cmd)
273 return cmd[1] << 16 | cmd[2] << 8 | cmd[3] << 0;
274
275 return 0;
276}
277
278static void fsl_espi_do_trans(struct spi_message *m,
279 struct fsl_espi_transfer *tr)
280{
281 struct spi_device *spi = m->spi;
282 struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
283 struct fsl_espi_transfer *espi_trans = tr;
284 struct spi_message message;
285 struct spi_transfer *t, *first, trans;
286 int status = 0;
287
288 spi_message_init(&message);
289 memset(&trans, 0, sizeof(trans));
290
291 first = list_first_entry(&m->transfers, struct spi_transfer,
292 transfer_list);
293 list_for_each_entry(t, &m->transfers, transfer_list) {
294 if ((first->bits_per_word != t->bits_per_word) ||
295 (first->speed_hz != t->speed_hz)) {
296 espi_trans->status = -EINVAL;
297 dev_err(mspi->dev, "bits_per_word/speed_hz should be"
298 " same for the same SPI transfer\n");
299 return;
300 }
301
302 trans.speed_hz = t->speed_hz;
303 trans.bits_per_word = t->bits_per_word;
304 trans.delay_usecs = max(first->delay_usecs, t->delay_usecs);
305 }
306
307 trans.len = espi_trans->len;
308 trans.tx_buf = espi_trans->tx_buf;
309 trans.rx_buf = espi_trans->rx_buf;
310 spi_message_add_tail(&trans, &message);
311
312 list_for_each_entry(t, &message.transfers, transfer_list) {
313 if (t->bits_per_word || t->speed_hz) {
314 status = -EINVAL;
315
316 status = fsl_espi_setup_transfer(spi, t);
317 if (status < 0)
318 break;
319 }
320
321 if (t->len)
322 status = fsl_espi_bufs(spi, t);
323
324 if (status) {
325 status = -EMSGSIZE;
326 break;
327 }
328
329 if (t->delay_usecs)
330 udelay(t->delay_usecs);
331 }
332
333 espi_trans->status = status;
334 fsl_espi_setup_transfer(spi, NULL);
335}
336
337static void fsl_espi_cmd_trans(struct spi_message *m,
338 struct fsl_espi_transfer *trans, u8 *rx_buff)
339{
340 struct spi_transfer *t;
341 u8 *local_buf;
342 int i = 0;
343 struct fsl_espi_transfer *espi_trans = trans;
344
345 local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
346 if (!local_buf) {
347 espi_trans->status = -ENOMEM;
348 return;
349 }
350
351 list_for_each_entry(t, &m->transfers, transfer_list) {
352 if (t->tx_buf) {
353 memcpy(local_buf + i, t->tx_buf, t->len);
354 i += t->len;
355 }
356 }
357
358 espi_trans->tx_buf = local_buf;
359 espi_trans->rx_buf = local_buf + espi_trans->n_tx;
360 fsl_espi_do_trans(m, espi_trans);
361
362 espi_trans->actual_length = espi_trans->len;
363 kfree(local_buf);
364}
365
366static void fsl_espi_rw_trans(struct spi_message *m,
367 struct fsl_espi_transfer *trans, u8 *rx_buff)
368{
369 struct fsl_espi_transfer *espi_trans = trans;
370 unsigned int n_tx = espi_trans->n_tx;
371 unsigned int n_rx = espi_trans->n_rx;
372 struct spi_transfer *t;
373 u8 *local_buf;
374 u8 *rx_buf = rx_buff;
375 unsigned int trans_len;
376 unsigned int addr;
377 int i, pos, loop;
378
379 local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
380 if (!local_buf) {
381 espi_trans->status = -ENOMEM;
382 return;
383 }
384
385 for (pos = 0, loop = 0; pos < n_rx; pos += trans_len, loop++) {
386 trans_len = n_rx - pos;
387 if (trans_len > SPCOM_TRANLEN_MAX - n_tx)
388 trans_len = SPCOM_TRANLEN_MAX - n_tx;
389
390 i = 0;
391 list_for_each_entry(t, &m->transfers, transfer_list) {
392 if (t->tx_buf) {
393 memcpy(local_buf + i, t->tx_buf, t->len);
394 i += t->len;
395 }
396 }
397
398 if (pos > 0) {
399 addr = fsl_espi_cmd2addr(local_buf);
400 addr += pos;
401 fsl_espi_addr2cmd(addr, local_buf);
402 }
403
404 espi_trans->n_tx = n_tx;
405 espi_trans->n_rx = trans_len;
406 espi_trans->len = trans_len + n_tx;
407 espi_trans->tx_buf = local_buf;
408 espi_trans->rx_buf = local_buf + n_tx;
409 fsl_espi_do_trans(m, espi_trans);
410
411 memcpy(rx_buf + pos, espi_trans->rx_buf + n_tx, trans_len);
412
413 if (loop > 0)
414 espi_trans->actual_length += espi_trans->len - n_tx;
415 else
416 espi_trans->actual_length += espi_trans->len;
417 }
418
419 kfree(local_buf);
420}
421
422static void fsl_espi_do_one_msg(struct spi_message *m)
423{
424 struct spi_transfer *t;
425 u8 *rx_buf = NULL;
426 unsigned int n_tx = 0;
427 unsigned int n_rx = 0;
428 struct fsl_espi_transfer espi_trans;
429
430 list_for_each_entry(t, &m->transfers, transfer_list) {
431 if (t->tx_buf)
432 n_tx += t->len;
433 if (t->rx_buf) {
434 n_rx += t->len;
435 rx_buf = t->rx_buf;
436 }
437 }
438
439 espi_trans.n_tx = n_tx;
440 espi_trans.n_rx = n_rx;
441 espi_trans.len = n_tx + n_rx;
442 espi_trans.actual_length = 0;
443 espi_trans.status = 0;
444
445 if (!rx_buf)
446 fsl_espi_cmd_trans(m, &espi_trans, NULL);
447 else
448 fsl_espi_rw_trans(m, &espi_trans, rx_buf);
449
450 m->actual_length = espi_trans.actual_length;
451 m->status = espi_trans.status;
452 m->complete(m->context);
453}
454
455static int fsl_espi_setup(struct spi_device *spi)
456{
457 struct mpc8xxx_spi *mpc8xxx_spi;
458 struct fsl_espi_reg *reg_base;
459 int retval;
460 u32 hw_mode;
461 u32 loop_mode;
462 struct spi_mpc8xxx_cs *cs = spi->controller_state;
463
464 if (!spi->max_speed_hz)
465 return -EINVAL;
466
467 if (!cs) {
468 cs = kzalloc(sizeof *cs, GFP_KERNEL);
469 if (!cs)
470 return -ENOMEM;
471 spi->controller_state = cs;
472 }
473
474 mpc8xxx_spi = spi_master_get_devdata(spi->master);
475 reg_base = mpc8xxx_spi->reg_base;
476
477 hw_mode = cs->hw_mode; /* Save original settings */
478 cs->hw_mode = mpc8xxx_spi_read_reg(
479 ®_base->csmode[spi->chip_select]);
480 /* mask out bits we are going to set */
481 cs->hw_mode &= ~(CSMODE_CP_BEGIN_EDGECLK | CSMODE_CI_INACTIVEHIGH
482 | CSMODE_REV);
483
484 if (spi->mode & SPI_CPHA)
485 cs->hw_mode |= CSMODE_CP_BEGIN_EDGECLK;
486 if (spi->mode & SPI_CPOL)
487 cs->hw_mode |= CSMODE_CI_INACTIVEHIGH;
488 if (!(spi->mode & SPI_LSB_FIRST))
489 cs->hw_mode |= CSMODE_REV;
490
491 /* Handle the loop mode */
492 loop_mode = mpc8xxx_spi_read_reg(®_base->mode);
493 loop_mode &= ~SPMODE_LOOP;
494 if (spi->mode & SPI_LOOP)
495 loop_mode |= SPMODE_LOOP;
496 mpc8xxx_spi_write_reg(®_base->mode, loop_mode);
497
498 retval = fsl_espi_setup_transfer(spi, NULL);
499 if (retval < 0) {
500 cs->hw_mode = hw_mode; /* Restore settings */
501 return retval;
502 }
503 return 0;
504}
505
506void fsl_espi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
507{
508 struct fsl_espi_reg *reg_base = mspi->reg_base;
509
510 /* We need handle RX first */
511 if (events & SPIE_NE) {
512 u32 rx_data, tmp;
513 u8 rx_data_8;
514
515 /* Spin until RX is done */
516 while (SPIE_RXCNT(events) < min(4, mspi->len)) {
517 cpu_relax();
518 events = mpc8xxx_spi_read_reg(®_base->event);
519 }
520
521 if (mspi->len >= 4) {
522 rx_data = mpc8xxx_spi_read_reg(®_base->receive);
523 } else {
524 tmp = mspi->len;
525 rx_data = 0;
526 while (tmp--) {
527 rx_data_8 = in_8((u8 *)®_base->receive);
528 rx_data |= (rx_data_8 << (tmp * 8));
529 }
530
531 rx_data <<= (4 - mspi->len) * 8;
532 }
533
534 mspi->len -= 4;
535
536 if (mspi->rx)
537 mspi->get_rx(rx_data, mspi);
538 }
539
540 if (!(events & SPIE_NF)) {
541 int ret;
542
543 /* spin until TX is done */
544 ret = spin_event_timeout(((events = mpc8xxx_spi_read_reg(
545 ®_base->event)) & SPIE_NF) == 0, 1000, 0);
546 if (!ret) {
547 dev_err(mspi->dev, "tired waiting for SPIE_NF\n");
548 return;
549 }
550 }
551
552 /* Clear the events */
553 mpc8xxx_spi_write_reg(®_base->event, events);
554
555 mspi->count -= 1;
556 if (mspi->count) {
557 u32 word = mspi->get_tx(mspi);
558
559 mpc8xxx_spi_write_reg(®_base->transmit, word);
560 } else {
561 complete(&mspi->done);
562 }
563}
564
565static irqreturn_t fsl_espi_irq(s32 irq, void *context_data)
566{
567 struct mpc8xxx_spi *mspi = context_data;
568 struct fsl_espi_reg *reg_base = mspi->reg_base;
569 irqreturn_t ret = IRQ_NONE;
570 u32 events;
571
572 /* Get interrupt events(tx/rx) */
573 events = mpc8xxx_spi_read_reg(®_base->event);
574 if (events)
575 ret = IRQ_HANDLED;
576
577 dev_vdbg(mspi->dev, "%s: events %x\n", __func__, events);
578
579 fsl_espi_cpu_irq(mspi, events);
580
581 return ret;
582}
583
584static void fsl_espi_remove(struct mpc8xxx_spi *mspi)
585{
586 iounmap(mspi->reg_base);
587}
588
589static struct spi_master * __devinit fsl_espi_probe(struct device *dev,
590 struct resource *mem, unsigned int irq)
591{
592 struct fsl_spi_platform_data *pdata = dev->platform_data;
593 struct spi_master *master;
594 struct mpc8xxx_spi *mpc8xxx_spi;
595 struct fsl_espi_reg *reg_base;
596 u32 regval;
597 int i, ret = 0;
598
599 master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
600 if (!master) {
601 ret = -ENOMEM;
602 goto err;
603 }
604
605 dev_set_drvdata(dev, master);
606
607 ret = mpc8xxx_spi_probe(dev, mem, irq);
608 if (ret)
609 goto err_probe;
610
611 master->setup = fsl_espi_setup;
612
613 mpc8xxx_spi = spi_master_get_devdata(master);
614 mpc8xxx_spi->spi_do_one_msg = fsl_espi_do_one_msg;
615 mpc8xxx_spi->spi_remove = fsl_espi_remove;
616
617 mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem));
618 if (!mpc8xxx_spi->reg_base) {
619 ret = -ENOMEM;
620 goto err_probe;
621 }
622
623 reg_base = mpc8xxx_spi->reg_base;
624
625 /* Register for SPI Interrupt */
626 ret = request_irq(mpc8xxx_spi->irq, fsl_espi_irq,
627 0, "fsl_espi", mpc8xxx_spi);
628 if (ret)
629 goto free_irq;
630
631 if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
632 mpc8xxx_spi->rx_shift = 16;
633 mpc8xxx_spi->tx_shift = 24;
634 }
635
636 /* SPI controller initializations */
637 mpc8xxx_spi_write_reg(®_base->mode, 0);
638 mpc8xxx_spi_write_reg(®_base->mask, 0);
639 mpc8xxx_spi_write_reg(®_base->command, 0);
640 mpc8xxx_spi_write_reg(®_base->event, 0xffffffff);
641
642 /* Init eSPI CS mode register */
643 for (i = 0; i < pdata->max_chipselect; i++)
644 mpc8xxx_spi_write_reg(®_base->csmode[i], CSMODE_INIT_VAL);
645
646 /* Enable SPI interface */
647 regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
648
649 mpc8xxx_spi_write_reg(®_base->mode, regval);
650
651 ret = spi_register_master(master);
652 if (ret < 0)
653 goto unreg_master;
654
655 dev_info(dev, "at 0x%p (irq = %d)\n", reg_base, mpc8xxx_spi->irq);
656
657 return master;
658
659unreg_master:
660 free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
661free_irq:
662 iounmap(mpc8xxx_spi->reg_base);
663err_probe:
664 spi_master_put(master);
665err:
666 return ERR_PTR(ret);
667}
668
669static int of_fsl_espi_get_chipselects(struct device *dev)
670{
671 struct device_node *np = dev->of_node;
672 struct fsl_spi_platform_data *pdata = dev->platform_data;
673 const u32 *prop;
674 int len;
675
676 prop = of_get_property(np, "fsl,espi-num-chipselects", &len);
677 if (!prop || len < sizeof(*prop)) {
678 dev_err(dev, "No 'fsl,espi-num-chipselects' property\n");
679 return -EINVAL;
680 }
681
682 pdata->max_chipselect = *prop;
683 pdata->cs_control = NULL;
684
685 return 0;
686}
687
688static int __devinit of_fsl_espi_probe(struct platform_device *ofdev)
689{
690 struct device *dev = &ofdev->dev;
691 struct device_node *np = ofdev->dev.of_node;
692 struct spi_master *master;
693 struct resource mem;
694 struct resource irq;
695 int ret = -ENOMEM;
696
697 ret = of_mpc8xxx_spi_probe(ofdev);
698 if (ret)
699 return ret;
700
701 ret = of_fsl_espi_get_chipselects(dev);
702 if (ret)
703 goto err;
704
705 ret = of_address_to_resource(np, 0, &mem);
706 if (ret)
707 goto err;
708
709 ret = of_irq_to_resource(np, 0, &irq);
710 if (!ret) {
711 ret = -EINVAL;
712 goto err;
713 }
714
715 master = fsl_espi_probe(dev, &mem, irq.start);
716 if (IS_ERR(master)) {
717 ret = PTR_ERR(master);
718 goto err;
719 }
720
721 return 0;
722
723err:
724 return ret;
725}
726
727static int __devexit of_fsl_espi_remove(struct platform_device *dev)
728{
729 return mpc8xxx_spi_remove(&dev->dev);
730}
731
732static const struct of_device_id of_fsl_espi_match[] = {
733 { .compatible = "fsl,mpc8536-espi" },
734 {}
735};
736MODULE_DEVICE_TABLE(of, of_fsl_espi_match);
737
738static struct platform_driver fsl_espi_driver = {
739 .driver = {
740 .name = "fsl_espi",
741 .owner = THIS_MODULE,
742 .of_match_table = of_fsl_espi_match,
743 },
744 .probe = of_fsl_espi_probe,
745 .remove = __devexit_p(of_fsl_espi_remove),
746};
747
748static int __init fsl_espi_init(void)
749{
750 return platform_driver_register(&fsl_espi_driver);
751}
752module_init(fsl_espi_init);
753
754static void __exit fsl_espi_exit(void)
755{
756 platform_driver_unregister(&fsl_espi_driver);
757}
758module_exit(fsl_espi_exit);
759
760MODULE_AUTHOR("Mingkai Hu");
761MODULE_DESCRIPTION("Enhanced Freescale SPI Driver");
762MODULE_LICENSE("GPL");
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 0x10000 /* 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 = ®_base->csmode[spi->chip_select];
97 __be32 __iomem *espi_mode = ®_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(®_base->mask, SPIM_NE);
212
213 /* transmit word */
214 word = mspi->get_tx(mspi);
215 mpc8xxx_spi_write_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 > 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(®_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(®_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 ®_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(®_base->mode);
509 loop_mode &= ~SPMODE_LOOP;
510 if (spi->mode & SPI_LOOP)
511 loop_mode |= SPMODE_LOOP;
512 mpc8xxx_spi_write_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(®_base->event);
547 }
548
549 if (mspi->len >= 4) {
550 rx_data = mpc8xxx_spi_read_reg(®_base->receive);
551 } else {
552 tmp = mspi->len;
553 rx_data = 0;
554 while (tmp--) {
555 rx_data_8 = in_8((u8 *)®_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 ®_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(®_base->event, events);
579 complete(&mspi->done);
580 return;
581 }
582 }
583
584 /* Clear the events */
585 mpc8xxx_spi_write_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(®_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(®_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(®_base->mode);
625 regval &= ~SPMODE_ENABLE;
626 mpc8xxx_spi_write_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(®_base->mode);
639 regval |= SPMODE_ENABLE;
640 mpc8xxx_spi_write_reg(®_base->mode, regval);
641
642 return 0;
643}
644#endif
645
646static size_t fsl_espi_max_transfer_size(struct spi_device *spi)
647{
648 return SPCOM_TRANLEN_MAX;
649}
650
651static struct spi_master * fsl_espi_probe(struct device *dev,
652 struct resource *mem, unsigned int irq)
653{
654 struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
655 struct spi_master *master;
656 struct mpc8xxx_spi *mpc8xxx_spi;
657 struct fsl_espi_reg *reg_base;
658 struct device_node *nc;
659 const __be32 *prop;
660 u32 regval, csmode;
661 int i, len, ret = 0;
662
663 master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
664 if (!master) {
665 ret = -ENOMEM;
666 goto err;
667 }
668
669 dev_set_drvdata(dev, master);
670
671 mpc8xxx_spi_probe(dev, mem, irq);
672
673 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
674 master->setup = fsl_espi_setup;
675 master->cleanup = fsl_espi_cleanup;
676 master->transfer_one_message = fsl_espi_do_one_msg;
677 master->auto_runtime_pm = true;
678 master->max_transfer_size = fsl_espi_max_transfer_size;
679
680 mpc8xxx_spi = spi_master_get_devdata(master);
681
682 mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem);
683 if (IS_ERR(mpc8xxx_spi->reg_base)) {
684 ret = PTR_ERR(mpc8xxx_spi->reg_base);
685 goto err_probe;
686 }
687
688 reg_base = mpc8xxx_spi->reg_base;
689
690 /* Register for SPI Interrupt */
691 ret = devm_request_irq(dev, mpc8xxx_spi->irq, fsl_espi_irq,
692 0, "fsl_espi", mpc8xxx_spi);
693 if (ret)
694 goto err_probe;
695
696 if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
697 mpc8xxx_spi->rx_shift = 16;
698 mpc8xxx_spi->tx_shift = 24;
699 }
700
701 /* SPI controller initializations */
702 mpc8xxx_spi_write_reg(®_base->mode, 0);
703 mpc8xxx_spi_write_reg(®_base->mask, 0);
704 mpc8xxx_spi_write_reg(®_base->command, 0);
705 mpc8xxx_spi_write_reg(®_base->event, 0xffffffff);
706
707 /* Init eSPI CS mode register */
708 for_each_available_child_of_node(master->dev.of_node, nc) {
709 /* get chip select */
710 prop = of_get_property(nc, "reg", &len);
711 if (!prop || len < sizeof(*prop))
712 continue;
713 i = be32_to_cpup(prop);
714 if (i < 0 || i >= pdata->max_chipselect)
715 continue;
716
717 csmode = CSMODE_INIT_VAL;
718 /* check if CSBEF is set in device tree */
719 prop = of_get_property(nc, "fsl,csbef", &len);
720 if (prop && len >= sizeof(*prop)) {
721 csmode &= ~(CSMODE_BEF(0xf));
722 csmode |= CSMODE_BEF(be32_to_cpup(prop));
723 }
724 /* check if CSAFT is set in device tree */
725 prop = of_get_property(nc, "fsl,csaft", &len);
726 if (prop && len >= sizeof(*prop)) {
727 csmode &= ~(CSMODE_AFT(0xf));
728 csmode |= CSMODE_AFT(be32_to_cpup(prop));
729 }
730 mpc8xxx_spi_write_reg(®_base->csmode[i], csmode);
731
732 dev_info(dev, "cs=%d, init_csmode=0x%x\n", i, csmode);
733 }
734
735 /* Enable SPI interface */
736 regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
737
738 mpc8xxx_spi_write_reg(®_base->mode, regval);
739
740 pm_runtime_set_autosuspend_delay(dev, AUTOSUSPEND_TIMEOUT);
741 pm_runtime_use_autosuspend(dev);
742 pm_runtime_set_active(dev);
743 pm_runtime_enable(dev);
744 pm_runtime_get_sync(dev);
745
746 ret = devm_spi_register_master(dev, master);
747 if (ret < 0)
748 goto err_pm;
749
750 dev_info(dev, "at 0x%p (irq = %d)\n", reg_base, mpc8xxx_spi->irq);
751
752 pm_runtime_mark_last_busy(dev);
753 pm_runtime_put_autosuspend(dev);
754
755 return master;
756
757err_pm:
758 pm_runtime_put_noidle(dev);
759 pm_runtime_disable(dev);
760 pm_runtime_set_suspended(dev);
761err_probe:
762 spi_master_put(master);
763err:
764 return ERR_PTR(ret);
765}
766
767static int of_fsl_espi_get_chipselects(struct device *dev)
768{
769 struct device_node *np = dev->of_node;
770 struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
771 const u32 *prop;
772 int len;
773
774 prop = of_get_property(np, "fsl,espi-num-chipselects", &len);
775 if (!prop || len < sizeof(*prop)) {
776 dev_err(dev, "No 'fsl,espi-num-chipselects' property\n");
777 return -EINVAL;
778 }
779
780 pdata->max_chipselect = *prop;
781 pdata->cs_control = NULL;
782
783 return 0;
784}
785
786static int of_fsl_espi_probe(struct platform_device *ofdev)
787{
788 struct device *dev = &ofdev->dev;
789 struct device_node *np = ofdev->dev.of_node;
790 struct spi_master *master;
791 struct resource mem;
792 unsigned int irq;
793 int ret = -ENOMEM;
794
795 ret = of_mpc8xxx_spi_probe(ofdev);
796 if (ret)
797 return ret;
798
799 ret = of_fsl_espi_get_chipselects(dev);
800 if (ret)
801 goto err;
802
803 ret = of_address_to_resource(np, 0, &mem);
804 if (ret)
805 goto err;
806
807 irq = irq_of_parse_and_map(np, 0);
808 if (!irq) {
809 ret = -EINVAL;
810 goto err;
811 }
812
813 master = fsl_espi_probe(dev, &mem, irq);
814 if (IS_ERR(master)) {
815 ret = PTR_ERR(master);
816 goto err;
817 }
818
819 return 0;
820
821err:
822 return ret;
823}
824
825static int of_fsl_espi_remove(struct platform_device *dev)
826{
827 pm_runtime_disable(&dev->dev);
828
829 return 0;
830}
831
832#ifdef CONFIG_PM_SLEEP
833static int of_fsl_espi_suspend(struct device *dev)
834{
835 struct spi_master *master = dev_get_drvdata(dev);
836 int ret;
837
838 ret = spi_master_suspend(master);
839 if (ret) {
840 dev_warn(dev, "cannot suspend master\n");
841 return ret;
842 }
843
844 ret = pm_runtime_force_suspend(dev);
845 if (ret < 0)
846 return ret;
847
848 return 0;
849}
850
851static int of_fsl_espi_resume(struct device *dev)
852{
853 struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
854 struct spi_master *master = dev_get_drvdata(dev);
855 struct mpc8xxx_spi *mpc8xxx_spi;
856 struct fsl_espi_reg *reg_base;
857 u32 regval;
858 int i, ret;
859
860 mpc8xxx_spi = spi_master_get_devdata(master);
861 reg_base = mpc8xxx_spi->reg_base;
862
863 /* SPI controller initializations */
864 mpc8xxx_spi_write_reg(®_base->mode, 0);
865 mpc8xxx_spi_write_reg(®_base->mask, 0);
866 mpc8xxx_spi_write_reg(®_base->command, 0);
867 mpc8xxx_spi_write_reg(®_base->event, 0xffffffff);
868
869 /* Init eSPI CS mode register */
870 for (i = 0; i < pdata->max_chipselect; i++)
871 mpc8xxx_spi_write_reg(®_base->csmode[i], CSMODE_INIT_VAL);
872
873 /* Enable SPI interface */
874 regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
875
876 mpc8xxx_spi_write_reg(®_base->mode, regval);
877
878 ret = pm_runtime_force_resume(dev);
879 if (ret < 0)
880 return ret;
881
882 return spi_master_resume(master);
883}
884#endif /* CONFIG_PM_SLEEP */
885
886static const struct dev_pm_ops espi_pm = {
887 SET_RUNTIME_PM_OPS(fsl_espi_runtime_suspend,
888 fsl_espi_runtime_resume, NULL)
889 SET_SYSTEM_SLEEP_PM_OPS(of_fsl_espi_suspend, of_fsl_espi_resume)
890};
891
892static const struct of_device_id of_fsl_espi_match[] = {
893 { .compatible = "fsl,mpc8536-espi" },
894 {}
895};
896MODULE_DEVICE_TABLE(of, of_fsl_espi_match);
897
898static struct platform_driver fsl_espi_driver = {
899 .driver = {
900 .name = "fsl_espi",
901 .of_match_table = of_fsl_espi_match,
902 .pm = &espi_pm,
903 },
904 .probe = of_fsl_espi_probe,
905 .remove = of_fsl_espi_remove,
906};
907module_platform_driver(fsl_espi_driver);
908
909MODULE_AUTHOR("Mingkai Hu");
910MODULE_DESCRIPTION("Enhanced Freescale SPI Driver");
911MODULE_LICENSE("GPL");