xref: /openbmc/linux/drivers/spi/spi-fsl-spi.c (revision 36acd5e2)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Freescale SPI controller driver.
4  *
5  * Maintainer: Kumar Gala
6  *
7  * Copyright (C) 2006 Polycom, Inc.
8  * Copyright 2010 Freescale Semiconductor, Inc.
9  *
10  * CPM SPI and QE buffer descriptors mode support:
11  * Copyright (c) 2009  MontaVista Software, Inc.
12  * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
13  *
14  * GRLIB support:
15  * Copyright (c) 2012 Aeroflex Gaisler AB.
16  * Author: Andreas Larsson <andreas@gaisler.com>
17  */
18 #include <linux/delay.h>
19 #include <linux/dma-mapping.h>
20 #include <linux/fsl_devices.h>
21 #include <linux/gpio/consumer.h>
22 #include <linux/interrupt.h>
23 #include <linux/irq.h>
24 #include <linux/kernel.h>
25 #include <linux/mm.h>
26 #include <linux/module.h>
27 #include <linux/mutex.h>
28 #include <linux/of.h>
29 #include <linux/of_address.h>
30 #include <linux/of_irq.h>
31 #include <linux/of_platform.h>
32 #include <linux/platform_device.h>
33 #include <linux/spi/spi.h>
34 #include <linux/spi/spi_bitbang.h>
35 #include <linux/types.h>
36 
37 #ifdef CONFIG_FSL_SOC
38 #include <sysdev/fsl_soc.h>
39 #endif
40 
41 /* Specific to the MPC8306/MPC8309 */
42 #define IMMR_SPI_CS_OFFSET 0x14c
43 #define SPI_BOOT_SEL_BIT   0x80000000
44 
45 #include "spi-fsl-lib.h"
46 #include "spi-fsl-cpm.h"
47 #include "spi-fsl-spi.h"
48 
49 #define TYPE_FSL	0
50 #define TYPE_GRLIB	1
51 
52 struct fsl_spi_match_data {
53 	int type;
54 };
55 
56 static struct fsl_spi_match_data of_fsl_spi_fsl_config = {
57 	.type = TYPE_FSL,
58 };
59 
60 static struct fsl_spi_match_data of_fsl_spi_grlib_config = {
61 	.type = TYPE_GRLIB,
62 };
63 
64 static const struct of_device_id of_fsl_spi_match[] = {
65 	{
66 		.compatible = "fsl,spi",
67 		.data = &of_fsl_spi_fsl_config,
68 	},
69 	{
70 		.compatible = "aeroflexgaisler,spictrl",
71 		.data = &of_fsl_spi_grlib_config,
72 	},
73 	{}
74 };
75 MODULE_DEVICE_TABLE(of, of_fsl_spi_match);
76 
77 static int fsl_spi_get_type(struct device *dev)
78 {
79 	const struct of_device_id *match;
80 
81 	if (dev->of_node) {
82 		match = of_match_node(of_fsl_spi_match, dev->of_node);
83 		if (match && match->data)
84 			return ((struct fsl_spi_match_data *)match->data)->type;
85 	}
86 	return TYPE_FSL;
87 }
88 
89 static void fsl_spi_change_mode(struct spi_device *spi)
90 {
91 	struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
92 	struct spi_mpc8xxx_cs *cs = spi->controller_state;
93 	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
94 	__be32 __iomem *mode = &reg_base->mode;
95 	unsigned long flags;
96 
97 	if (cs->hw_mode == mpc8xxx_spi_read_reg(mode))
98 		return;
99 
100 	/* Turn off IRQs locally to minimize time that SPI is disabled. */
101 	local_irq_save(flags);
102 
103 	/* Turn off SPI unit prior changing mode */
104 	mpc8xxx_spi_write_reg(mode, cs->hw_mode & ~SPMODE_ENABLE);
105 
106 	/* When in CPM mode, we need to reinit tx and rx. */
107 	if (mspi->flags & SPI_CPM_MODE) {
108 		fsl_spi_cpm_reinit_txrx(mspi);
109 	}
110 	mpc8xxx_spi_write_reg(mode, cs->hw_mode);
111 	local_irq_restore(flags);
112 }
113 
114 static void fsl_spi_chipselect(struct spi_device *spi, int value)
115 {
116 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
117 	struct fsl_spi_platform_data *pdata;
118 	bool pol = spi->mode & SPI_CS_HIGH;
119 	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
120 
121 	pdata = spi->dev.parent->parent->platform_data;
122 
123 	if (value == BITBANG_CS_INACTIVE) {
124 		if (pdata->cs_control)
125 			pdata->cs_control(spi, !pol);
126 	}
127 
128 	if (value == BITBANG_CS_ACTIVE) {
129 		mpc8xxx_spi->rx_shift = cs->rx_shift;
130 		mpc8xxx_spi->tx_shift = cs->tx_shift;
131 		mpc8xxx_spi->get_rx = cs->get_rx;
132 		mpc8xxx_spi->get_tx = cs->get_tx;
133 
134 		fsl_spi_change_mode(spi);
135 
136 		if (pdata->cs_control)
137 			pdata->cs_control(spi, pol);
138 	}
139 }
140 
141 static void fsl_spi_qe_cpu_set_shifts(u32 *rx_shift, u32 *tx_shift,
142 				      int bits_per_word, int msb_first)
143 {
144 	*rx_shift = 0;
145 	*tx_shift = 0;
146 	if (msb_first) {
147 		if (bits_per_word <= 8) {
148 			*rx_shift = 16;
149 			*tx_shift = 24;
150 		} else if (bits_per_word <= 16) {
151 			*rx_shift = 16;
152 			*tx_shift = 16;
153 		}
154 	} else {
155 		if (bits_per_word <= 8)
156 			*rx_shift = 8;
157 	}
158 }
159 
160 static void fsl_spi_grlib_set_shifts(u32 *rx_shift, u32 *tx_shift,
161 				     int bits_per_word, int msb_first)
162 {
163 	*rx_shift = 0;
164 	*tx_shift = 0;
165 	if (bits_per_word <= 16) {
166 		if (msb_first) {
167 			*rx_shift = 16; /* LSB in bit 16 */
168 			*tx_shift = 32 - bits_per_word; /* MSB in bit 31 */
169 		} else {
170 			*rx_shift = 16 - bits_per_word; /* MSB in bit 15 */
171 		}
172 	}
173 }
174 
175 static int mspi_apply_cpu_mode_quirks(struct spi_mpc8xxx_cs *cs,
176 				struct spi_device *spi,
177 				struct mpc8xxx_spi *mpc8xxx_spi,
178 				int bits_per_word)
179 {
180 	cs->rx_shift = 0;
181 	cs->tx_shift = 0;
182 	if (bits_per_word <= 8) {
183 		cs->get_rx = mpc8xxx_spi_rx_buf_u8;
184 		cs->get_tx = mpc8xxx_spi_tx_buf_u8;
185 	} else if (bits_per_word <= 16) {
186 		cs->get_rx = mpc8xxx_spi_rx_buf_u16;
187 		cs->get_tx = mpc8xxx_spi_tx_buf_u16;
188 	} else if (bits_per_word <= 32) {
189 		cs->get_rx = mpc8xxx_spi_rx_buf_u32;
190 		cs->get_tx = mpc8xxx_spi_tx_buf_u32;
191 	} else
192 		return -EINVAL;
193 
194 	if (mpc8xxx_spi->set_shifts)
195 		mpc8xxx_spi->set_shifts(&cs->rx_shift, &cs->tx_shift,
196 					bits_per_word,
197 					!(spi->mode & SPI_LSB_FIRST));
198 
199 	mpc8xxx_spi->rx_shift = cs->rx_shift;
200 	mpc8xxx_spi->tx_shift = cs->tx_shift;
201 	mpc8xxx_spi->get_rx = cs->get_rx;
202 	mpc8xxx_spi->get_tx = cs->get_tx;
203 
204 	return bits_per_word;
205 }
206 
207 static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs,
208 				struct spi_device *spi,
209 				int bits_per_word)
210 {
211 	/* QE uses Little Endian for words > 8
212 	 * so transform all words > 8 into 8 bits
213 	 * Unfortnatly that doesn't work for LSB so
214 	 * reject these for now */
215 	/* Note: 32 bits word, LSB works iff
216 	 * tfcr/rfcr is set to CPMFCR_GBL */
217 	if (spi->mode & SPI_LSB_FIRST &&
218 	    bits_per_word > 8)
219 		return -EINVAL;
220 	if (bits_per_word > 8)
221 		return 8; /* pretend its 8 bits */
222 	return bits_per_word;
223 }
224 
225 static int fsl_spi_setup_transfer(struct spi_device *spi,
226 					struct spi_transfer *t)
227 {
228 	struct mpc8xxx_spi *mpc8xxx_spi;
229 	int bits_per_word = 0;
230 	u8 pm;
231 	u32 hz = 0;
232 	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
233 
234 	mpc8xxx_spi = spi_master_get_devdata(spi->master);
235 
236 	if (t) {
237 		bits_per_word = t->bits_per_word;
238 		hz = t->speed_hz;
239 	}
240 
241 	/* spi_transfer level calls that work per-word */
242 	if (!bits_per_word)
243 		bits_per_word = spi->bits_per_word;
244 
245 	if (!hz)
246 		hz = spi->max_speed_hz;
247 
248 	if (!(mpc8xxx_spi->flags & SPI_CPM_MODE))
249 		bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi,
250 							   mpc8xxx_spi,
251 							   bits_per_word);
252 	else if (mpc8xxx_spi->flags & SPI_QE)
253 		bits_per_word = mspi_apply_qe_mode_quirks(cs, spi,
254 							  bits_per_word);
255 
256 	if (bits_per_word < 0)
257 		return bits_per_word;
258 
259 	if (bits_per_word == 32)
260 		bits_per_word = 0;
261 	else
262 		bits_per_word = bits_per_word - 1;
263 
264 	/* mask out bits we are going to set */
265 	cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16
266 				  | SPMODE_PM(0xF));
267 
268 	cs->hw_mode |= SPMODE_LEN(bits_per_word);
269 
270 	if ((mpc8xxx_spi->spibrg / hz) > 64) {
271 		cs->hw_mode |= SPMODE_DIV16;
272 		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
273 		WARN_ONCE(pm > 16,
274 			  "%s: Requested speed is too low: %d Hz. Will use %d Hz instead.\n",
275 			  dev_name(&spi->dev), hz, mpc8xxx_spi->spibrg / 1024);
276 		if (pm > 16)
277 			pm = 16;
278 	} else {
279 		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
280 	}
281 	if (pm)
282 		pm--;
283 
284 	cs->hw_mode |= SPMODE_PM(pm);
285 
286 	fsl_spi_change_mode(spi);
287 	return 0;
288 }
289 
290 static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi,
291 				struct spi_transfer *t, unsigned int len)
292 {
293 	u32 word;
294 	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
295 
296 	mspi->count = len;
297 
298 	/* enable rx ints */
299 	mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
300 
301 	/* transmit word */
302 	word = mspi->get_tx(mspi);
303 	mpc8xxx_spi_write_reg(&reg_base->transmit, word);
304 
305 	return 0;
306 }
307 
308 static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t,
309 			    bool is_dma_mapped)
310 {
311 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
312 	struct fsl_spi_reg __iomem *reg_base;
313 	unsigned int len = t->len;
314 	u8 bits_per_word;
315 	int ret;
316 
317 	reg_base = mpc8xxx_spi->reg_base;
318 	bits_per_word = spi->bits_per_word;
319 	if (t->bits_per_word)
320 		bits_per_word = t->bits_per_word;
321 
322 	if (bits_per_word > 8) {
323 		/* invalid length? */
324 		if (len & 1)
325 			return -EINVAL;
326 		len /= 2;
327 	}
328 	if (bits_per_word > 16) {
329 		/* invalid length? */
330 		if (len & 1)
331 			return -EINVAL;
332 		len /= 2;
333 	}
334 
335 	mpc8xxx_spi->tx = t->tx_buf;
336 	mpc8xxx_spi->rx = t->rx_buf;
337 
338 	reinit_completion(&mpc8xxx_spi->done);
339 
340 	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
341 		ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped);
342 	else
343 		ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len);
344 	if (ret)
345 		return ret;
346 
347 	wait_for_completion(&mpc8xxx_spi->done);
348 
349 	/* disable rx ints */
350 	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
351 
352 	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
353 		fsl_spi_cpm_bufs_complete(mpc8xxx_spi);
354 
355 	return mpc8xxx_spi->count;
356 }
357 
358 static int fsl_spi_do_one_msg(struct spi_master *master,
359 			      struct spi_message *m)
360 {
361 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
362 	struct spi_device *spi = m->spi;
363 	struct spi_transfer *t, *first;
364 	unsigned int cs_change;
365 	const int nsecs = 50;
366 	int status, last_bpw;
367 
368 	/*
369 	 * In CPU mode, optimize large byte transfers to use larger
370 	 * bits_per_word values to reduce number of interrupts taken.
371 	 */
372 	if (!(mpc8xxx_spi->flags & SPI_CPM_MODE)) {
373 		list_for_each_entry(t, &m->transfers, transfer_list) {
374 			if (t->len < 256 || t->bits_per_word != 8)
375 				continue;
376 			if ((t->len & 3) == 0)
377 				t->bits_per_word = 32;
378 			else if ((t->len & 1) == 0)
379 				t->bits_per_word = 16;
380 		}
381 	}
382 
383 	/* Don't allow changes if CS is active */
384 	cs_change = 1;
385 	list_for_each_entry(t, &m->transfers, transfer_list) {
386 		if (cs_change)
387 			first = t;
388 		cs_change = t->cs_change;
389 		if (first->speed_hz != t->speed_hz) {
390 			dev_err(&spi->dev,
391 				"speed_hz cannot change while CS is active\n");
392 			return -EINVAL;
393 		}
394 	}
395 
396 	last_bpw = -1;
397 	cs_change = 1;
398 	status = -EINVAL;
399 	list_for_each_entry(t, &m->transfers, transfer_list) {
400 		if (cs_change || last_bpw != t->bits_per_word)
401 			status = fsl_spi_setup_transfer(spi, t);
402 		if (status < 0)
403 			break;
404 		last_bpw = t->bits_per_word;
405 
406 		if (cs_change) {
407 			fsl_spi_chipselect(spi, BITBANG_CS_ACTIVE);
408 			ndelay(nsecs);
409 		}
410 		cs_change = t->cs_change;
411 		if (t->len)
412 			status = fsl_spi_bufs(spi, t, m->is_dma_mapped);
413 		if (status) {
414 			status = -EMSGSIZE;
415 			break;
416 		}
417 		m->actual_length += t->len;
418 
419 		spi_transfer_delay_exec(t);
420 
421 		if (cs_change) {
422 			ndelay(nsecs);
423 			fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
424 			ndelay(nsecs);
425 		}
426 	}
427 
428 	m->status = status;
429 
430 	if (status || !cs_change) {
431 		ndelay(nsecs);
432 		fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
433 	}
434 
435 	fsl_spi_setup_transfer(spi, NULL);
436 	spi_finalize_current_message(master);
437 	return 0;
438 }
439 
440 static int fsl_spi_setup(struct spi_device *spi)
441 {
442 	struct mpc8xxx_spi *mpc8xxx_spi;
443 	struct fsl_spi_reg __iomem *reg_base;
444 	int retval;
445 	u32 hw_mode;
446 	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
447 
448 	if (!spi->max_speed_hz)
449 		return -EINVAL;
450 
451 	if (!cs) {
452 		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
453 		if (!cs)
454 			return -ENOMEM;
455 		spi_set_ctldata(spi, cs);
456 	}
457 	mpc8xxx_spi = spi_master_get_devdata(spi->master);
458 
459 	reg_base = mpc8xxx_spi->reg_base;
460 
461 	hw_mode = cs->hw_mode; /* Save original settings */
462 	cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
463 	/* mask out bits we are going to set */
464 	cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
465 			 | SPMODE_REV | SPMODE_LOOP);
466 
467 	if (spi->mode & SPI_CPHA)
468 		cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
469 	if (spi->mode & SPI_CPOL)
470 		cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
471 	if (!(spi->mode & SPI_LSB_FIRST))
472 		cs->hw_mode |= SPMODE_REV;
473 	if (spi->mode & SPI_LOOP)
474 		cs->hw_mode |= SPMODE_LOOP;
475 
476 	retval = fsl_spi_setup_transfer(spi, NULL);
477 	if (retval < 0) {
478 		cs->hw_mode = hw_mode; /* Restore settings */
479 		return retval;
480 	}
481 
482 	/* Initialize chipselect - might be active for SPI_CS_HIGH mode */
483 	fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
484 
485 	return 0;
486 }
487 
488 static void fsl_spi_cleanup(struct spi_device *spi)
489 {
490 	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
491 
492 	kfree(cs);
493 	spi_set_ctldata(spi, NULL);
494 }
495 
496 static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
497 {
498 	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
499 
500 	/* We need handle RX first */
501 	if (events & SPIE_NE) {
502 		u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
503 
504 		if (mspi->rx)
505 			mspi->get_rx(rx_data, mspi);
506 	}
507 
508 	if ((events & SPIE_NF) == 0)
509 		/* spin until TX is done */
510 		while (((events =
511 			mpc8xxx_spi_read_reg(&reg_base->event)) &
512 						SPIE_NF) == 0)
513 			cpu_relax();
514 
515 	/* Clear the events */
516 	mpc8xxx_spi_write_reg(&reg_base->event, events);
517 
518 	mspi->count -= 1;
519 	if (mspi->count) {
520 		u32 word = mspi->get_tx(mspi);
521 
522 		mpc8xxx_spi_write_reg(&reg_base->transmit, word);
523 	} else {
524 		complete(&mspi->done);
525 	}
526 }
527 
528 static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
529 {
530 	struct mpc8xxx_spi *mspi = context_data;
531 	irqreturn_t ret = IRQ_NONE;
532 	u32 events;
533 	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
534 
535 	/* Get interrupt events(tx/rx) */
536 	events = mpc8xxx_spi_read_reg(&reg_base->event);
537 	if (events)
538 		ret = IRQ_HANDLED;
539 
540 	dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
541 
542 	if (mspi->flags & SPI_CPM_MODE)
543 		fsl_spi_cpm_irq(mspi, events);
544 	else
545 		fsl_spi_cpu_irq(mspi, events);
546 
547 	return ret;
548 }
549 
550 static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on)
551 {
552 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
553 	struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base;
554 	u32 slvsel;
555 	u16 cs = spi->chip_select;
556 
557 	if (spi->cs_gpiod) {
558 		gpiod_set_value(spi->cs_gpiod, on);
559 	} else if (cs < mpc8xxx_spi->native_chipselects) {
560 		slvsel = mpc8xxx_spi_read_reg(&reg_base->slvsel);
561 		slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs));
562 		mpc8xxx_spi_write_reg(&reg_base->slvsel, slvsel);
563 	}
564 }
565 
566 static void fsl_spi_grlib_probe(struct device *dev)
567 {
568 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
569 	struct spi_master *master = dev_get_drvdata(dev);
570 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
571 	struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base;
572 	int mbits;
573 	u32 capabilities;
574 
575 	capabilities = mpc8xxx_spi_read_reg(&reg_base->cap);
576 
577 	mpc8xxx_spi->set_shifts = fsl_spi_grlib_set_shifts;
578 	mbits = SPCAP_MAXWLEN(capabilities);
579 	if (mbits)
580 		mpc8xxx_spi->max_bits_per_word = mbits + 1;
581 
582 	mpc8xxx_spi->native_chipselects = 0;
583 	if (SPCAP_SSEN(capabilities)) {
584 		mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities);
585 		mpc8xxx_spi_write_reg(&reg_base->slvsel, 0xffffffff);
586 	}
587 	master->num_chipselect = mpc8xxx_spi->native_chipselects;
588 	pdata->cs_control = fsl_spi_grlib_cs_control;
589 }
590 
591 static struct spi_master *fsl_spi_probe(struct device *dev,
592 		struct resource *mem, unsigned int irq)
593 {
594 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
595 	struct spi_master *master;
596 	struct mpc8xxx_spi *mpc8xxx_spi;
597 	struct fsl_spi_reg __iomem *reg_base;
598 	u32 regval;
599 	int ret = 0;
600 
601 	master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
602 	if (master == NULL) {
603 		ret = -ENOMEM;
604 		goto err;
605 	}
606 
607 	dev_set_drvdata(dev, master);
608 
609 	mpc8xxx_spi_probe(dev, mem, irq);
610 
611 	master->setup = fsl_spi_setup;
612 	master->cleanup = fsl_spi_cleanup;
613 	master->transfer_one_message = fsl_spi_do_one_msg;
614 	master->use_gpio_descriptors = true;
615 
616 	mpc8xxx_spi = spi_master_get_devdata(master);
617 	mpc8xxx_spi->max_bits_per_word = 32;
618 	mpc8xxx_spi->type = fsl_spi_get_type(dev);
619 
620 	ret = fsl_spi_cpm_init(mpc8xxx_spi);
621 	if (ret)
622 		goto err_cpm_init;
623 
624 	mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem);
625 	if (IS_ERR(mpc8xxx_spi->reg_base)) {
626 		ret = PTR_ERR(mpc8xxx_spi->reg_base);
627 		goto err_probe;
628 	}
629 
630 	if (mpc8xxx_spi->type == TYPE_GRLIB)
631 		fsl_spi_grlib_probe(dev);
632 
633 	master->bits_per_word_mask =
634 		(SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32)) &
635 		SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word);
636 
637 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
638 		mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts;
639 
640 	if (mpc8xxx_spi->set_shifts)
641 		/* 8 bits per word and MSB first */
642 		mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift,
643 					&mpc8xxx_spi->tx_shift, 8, 1);
644 
645 	/* Register for SPI Interrupt */
646 	ret = devm_request_irq(dev, mpc8xxx_spi->irq, fsl_spi_irq,
647 			       0, "fsl_spi", mpc8xxx_spi);
648 
649 	if (ret != 0)
650 		goto err_probe;
651 
652 	reg_base = mpc8xxx_spi->reg_base;
653 
654 	/* SPI controller initializations */
655 	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
656 	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
657 	mpc8xxx_spi_write_reg(&reg_base->command, 0);
658 	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
659 
660 	/* Enable SPI interface */
661 	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
662 	if (mpc8xxx_spi->max_bits_per_word < 8) {
663 		regval &= ~SPMODE_LEN(0xF);
664 		regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1);
665 	}
666 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
667 		regval |= SPMODE_OP;
668 
669 	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
670 
671 	ret = devm_spi_register_master(dev, master);
672 	if (ret < 0)
673 		goto err_probe;
674 
675 	dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
676 		 mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
677 
678 	return master;
679 
680 err_probe:
681 	fsl_spi_cpm_free(mpc8xxx_spi);
682 err_cpm_init:
683 	spi_master_put(master);
684 err:
685 	return ERR_PTR(ret);
686 }
687 
688 static void fsl_spi_cs_control(struct spi_device *spi, bool on)
689 {
690 	if (spi->cs_gpiod) {
691 		gpiod_set_value(spi->cs_gpiod, on);
692 	} else {
693 		struct device *dev = spi->dev.parent->parent;
694 		struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
695 		struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
696 
697 		if (WARN_ON_ONCE(!pinfo->immr_spi_cs))
698 			return;
699 		iowrite32be(on ? SPI_BOOT_SEL_BIT : 0, pinfo->immr_spi_cs);
700 	}
701 }
702 
703 static int of_fsl_spi_probe(struct platform_device *ofdev)
704 {
705 	struct device *dev = &ofdev->dev;
706 	struct device_node *np = ofdev->dev.of_node;
707 	struct spi_master *master;
708 	struct resource mem;
709 	int irq, type;
710 	int ret;
711 
712 	ret = of_mpc8xxx_spi_probe(ofdev);
713 	if (ret)
714 		return ret;
715 
716 	type = fsl_spi_get_type(&ofdev->dev);
717 	if (type == TYPE_FSL) {
718 		struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
719 		bool spisel_boot = false;
720 #if IS_ENABLED(CONFIG_FSL_SOC)
721 		struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
722 
723 		spisel_boot = of_property_read_bool(np, "fsl,spisel_boot");
724 		if (spisel_boot) {
725 			pinfo->immr_spi_cs = ioremap(get_immrbase() + IMMR_SPI_CS_OFFSET, 4);
726 			if (!pinfo->immr_spi_cs)
727 				return -ENOMEM;
728 		}
729 #endif
730 		/*
731 		 * Handle the case where we have one hardwired (always selected)
732 		 * device on the first "chipselect". Else we let the core code
733 		 * handle any GPIOs or native chip selects and assign the
734 		 * appropriate callback for dealing with the CS lines. This isn't
735 		 * supported on the GRLIB variant.
736 		 */
737 		ret = gpiod_count(dev, "cs");
738 		if (ret < 0)
739 			ret = 0;
740 		if (ret == 0 && !spisel_boot) {
741 			pdata->max_chipselect = 1;
742 		} else {
743 			pdata->max_chipselect = ret + spisel_boot;
744 			pdata->cs_control = fsl_spi_cs_control;
745 		}
746 	}
747 
748 	ret = of_address_to_resource(np, 0, &mem);
749 	if (ret)
750 		return ret;
751 
752 	irq = platform_get_irq(ofdev, 0);
753 	if (irq < 0)
754 		return irq;
755 
756 	master = fsl_spi_probe(dev, &mem, irq);
757 
758 	return PTR_ERR_OR_ZERO(master);
759 }
760 
761 static int of_fsl_spi_remove(struct platform_device *ofdev)
762 {
763 	struct spi_master *master = platform_get_drvdata(ofdev);
764 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
765 
766 	fsl_spi_cpm_free(mpc8xxx_spi);
767 	return 0;
768 }
769 
770 static struct platform_driver of_fsl_spi_driver = {
771 	.driver = {
772 		.name = "fsl_spi",
773 		.of_match_table = of_fsl_spi_match,
774 	},
775 	.probe		= of_fsl_spi_probe,
776 	.remove		= of_fsl_spi_remove,
777 };
778 
779 #ifdef CONFIG_MPC832x_RDB
780 /*
781  * XXX XXX XXX
782  * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
783  * only. The driver should go away soon, since newer MPC8323E-RDB's device
784  * tree can work with OpenFirmware driver. But for now we support old trees
785  * as well.
786  */
787 static int plat_mpc8xxx_spi_probe(struct platform_device *pdev)
788 {
789 	struct resource *mem;
790 	int irq;
791 	struct spi_master *master;
792 
793 	if (!dev_get_platdata(&pdev->dev))
794 		return -EINVAL;
795 
796 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
797 	if (!mem)
798 		return -EINVAL;
799 
800 	irq = platform_get_irq(pdev, 0);
801 	if (irq <= 0)
802 		return -EINVAL;
803 
804 	master = fsl_spi_probe(&pdev->dev, mem, irq);
805 	return PTR_ERR_OR_ZERO(master);
806 }
807 
808 static int plat_mpc8xxx_spi_remove(struct platform_device *pdev)
809 {
810 	struct spi_master *master = platform_get_drvdata(pdev);
811 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
812 
813 	fsl_spi_cpm_free(mpc8xxx_spi);
814 
815 	return 0;
816 }
817 
818 MODULE_ALIAS("platform:mpc8xxx_spi");
819 static struct platform_driver mpc8xxx_spi_driver = {
820 	.probe = plat_mpc8xxx_spi_probe,
821 	.remove = plat_mpc8xxx_spi_remove,
822 	.driver = {
823 		.name = "mpc8xxx_spi",
824 	},
825 };
826 
827 static bool legacy_driver_failed;
828 
829 static void __init legacy_driver_register(void)
830 {
831 	legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
832 }
833 
834 static void __exit legacy_driver_unregister(void)
835 {
836 	if (legacy_driver_failed)
837 		return;
838 	platform_driver_unregister(&mpc8xxx_spi_driver);
839 }
840 #else
841 static void __init legacy_driver_register(void) {}
842 static void __exit legacy_driver_unregister(void) {}
843 #endif /* CONFIG_MPC832x_RDB */
844 
845 static int __init fsl_spi_init(void)
846 {
847 	legacy_driver_register();
848 	return platform_driver_register(&of_fsl_spi_driver);
849 }
850 module_init(fsl_spi_init);
851 
852 static void __exit fsl_spi_exit(void)
853 {
854 	platform_driver_unregister(&of_fsl_spi_driver);
855 	legacy_driver_unregister();
856 }
857 module_exit(fsl_spi_exit);
858 
859 MODULE_AUTHOR("Kumar Gala");
860 MODULE_DESCRIPTION("Simple Freescale SPI Driver");
861 MODULE_LICENSE("GPL");
862