xref: /linux/drivers/spi/spi-fsl-spi.c (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
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 	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
119 
120 	pdata = spi->dev.parent->parent->platform_data;
121 
122 	if (value == BITBANG_CS_INACTIVE) {
123 		if (pdata->cs_control)
124 			pdata->cs_control(spi, false);
125 	}
126 
127 	if (value == BITBANG_CS_ACTIVE) {
128 		mpc8xxx_spi->rx_shift = cs->rx_shift;
129 		mpc8xxx_spi->tx_shift = cs->tx_shift;
130 		mpc8xxx_spi->get_rx = cs->get_rx;
131 		mpc8xxx_spi->get_tx = cs->get_tx;
132 
133 		fsl_spi_change_mode(spi);
134 
135 		if (pdata->cs_control)
136 			pdata->cs_control(spi, true);
137 	}
138 }
139 
140 static void fsl_spi_qe_cpu_set_shifts(u32 *rx_shift, u32 *tx_shift,
141 				      int bits_per_word, int msb_first)
142 {
143 	*rx_shift = 0;
144 	*tx_shift = 0;
145 	if (msb_first) {
146 		if (bits_per_word <= 8) {
147 			*rx_shift = 16;
148 			*tx_shift = 24;
149 		} else if (bits_per_word <= 16) {
150 			*rx_shift = 16;
151 			*tx_shift = 16;
152 		}
153 	} else {
154 		if (bits_per_word <= 8)
155 			*rx_shift = 8;
156 	}
157 }
158 
159 static void fsl_spi_grlib_set_shifts(u32 *rx_shift, u32 *tx_shift,
160 				     int bits_per_word, int msb_first)
161 {
162 	*rx_shift = 0;
163 	*tx_shift = 0;
164 	if (bits_per_word <= 16) {
165 		if (msb_first) {
166 			*rx_shift = 16; /* LSB in bit 16 */
167 			*tx_shift = 32 - bits_per_word; /* MSB in bit 31 */
168 		} else {
169 			*rx_shift = 16 - bits_per_word; /* MSB in bit 15 */
170 		}
171 	}
172 }
173 
174 static int mspi_apply_cpu_mode_quirks(struct spi_mpc8xxx_cs *cs,
175 				struct spi_device *spi,
176 				struct mpc8xxx_spi *mpc8xxx_spi,
177 				int bits_per_word)
178 {
179 	cs->rx_shift = 0;
180 	cs->tx_shift = 0;
181 	if (bits_per_word <= 8) {
182 		cs->get_rx = mpc8xxx_spi_rx_buf_u8;
183 		cs->get_tx = mpc8xxx_spi_tx_buf_u8;
184 	} else if (bits_per_word <= 16) {
185 		cs->get_rx = mpc8xxx_spi_rx_buf_u16;
186 		cs->get_tx = mpc8xxx_spi_tx_buf_u16;
187 	} else if (bits_per_word <= 32) {
188 		cs->get_rx = mpc8xxx_spi_rx_buf_u32;
189 		cs->get_tx = mpc8xxx_spi_tx_buf_u32;
190 	} else
191 		return -EINVAL;
192 
193 	if (mpc8xxx_spi->set_shifts)
194 		mpc8xxx_spi->set_shifts(&cs->rx_shift, &cs->tx_shift,
195 					bits_per_word,
196 					!(spi->mode & SPI_LSB_FIRST));
197 
198 	mpc8xxx_spi->rx_shift = cs->rx_shift;
199 	mpc8xxx_spi->tx_shift = cs->tx_shift;
200 	mpc8xxx_spi->get_rx = cs->get_rx;
201 	mpc8xxx_spi->get_tx = cs->get_tx;
202 
203 	return bits_per_word;
204 }
205 
206 static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs,
207 				struct spi_device *spi,
208 				int bits_per_word)
209 {
210 	/* QE uses Little Endian for words > 8
211 	 * so transform all words > 8 into 8 bits
212 	 * Unfortnatly that doesn't work for LSB so
213 	 * reject these for now */
214 	/* Note: 32 bits word, LSB works iff
215 	 * tfcr/rfcr is set to CPMFCR_GBL */
216 	if (spi->mode & SPI_LSB_FIRST &&
217 	    bits_per_word > 8)
218 		return -EINVAL;
219 	if (bits_per_word > 8)
220 		return 8; /* pretend its 8 bits */
221 	return bits_per_word;
222 }
223 
224 static int fsl_spi_setup_transfer(struct spi_device *spi,
225 					struct spi_transfer *t)
226 {
227 	struct mpc8xxx_spi *mpc8xxx_spi;
228 	int bits_per_word = 0;
229 	u8 pm;
230 	u32 hz = 0;
231 	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
232 
233 	mpc8xxx_spi = spi_master_get_devdata(spi->master);
234 
235 	if (t) {
236 		bits_per_word = t->bits_per_word;
237 		hz = t->speed_hz;
238 	}
239 
240 	/* spi_transfer level calls that work per-word */
241 	if (!bits_per_word)
242 		bits_per_word = spi->bits_per_word;
243 
244 	if (!hz)
245 		hz = spi->max_speed_hz;
246 
247 	if (!(mpc8xxx_spi->flags & SPI_CPM_MODE))
248 		bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi,
249 							   mpc8xxx_spi,
250 							   bits_per_word);
251 	else if (mpc8xxx_spi->flags & SPI_QE)
252 		bits_per_word = mspi_apply_qe_mode_quirks(cs, spi,
253 							  bits_per_word);
254 
255 	if (bits_per_word < 0)
256 		return bits_per_word;
257 
258 	if (bits_per_word == 32)
259 		bits_per_word = 0;
260 	else
261 		bits_per_word = bits_per_word - 1;
262 
263 	/* mask out bits we are going to set */
264 	cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16
265 				  | SPMODE_PM(0xF));
266 
267 	cs->hw_mode |= SPMODE_LEN(bits_per_word);
268 
269 	if ((mpc8xxx_spi->spibrg / hz) > 64) {
270 		cs->hw_mode |= SPMODE_DIV16;
271 		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
272 		WARN_ONCE(pm > 16,
273 			  "%s: Requested speed is too low: %d Hz. Will use %d Hz instead.\n",
274 			  dev_name(&spi->dev), hz, mpc8xxx_spi->spibrg / 1024);
275 		if (pm > 16)
276 			pm = 16;
277 	} else {
278 		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
279 	}
280 	if (pm)
281 		pm--;
282 
283 	cs->hw_mode |= SPMODE_PM(pm);
284 
285 	fsl_spi_change_mode(spi);
286 	return 0;
287 }
288 
289 static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi,
290 				struct spi_transfer *t, unsigned int len)
291 {
292 	u32 word;
293 	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
294 
295 	mspi->count = len;
296 
297 	/* enable rx ints */
298 	mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
299 
300 	/* transmit word */
301 	word = mspi->get_tx(mspi);
302 	mpc8xxx_spi_write_reg(&reg_base->transmit, word);
303 
304 	return 0;
305 }
306 
307 static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t,
308 			    bool is_dma_mapped)
309 {
310 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
311 	struct fsl_spi_reg __iomem *reg_base;
312 	unsigned int len = t->len;
313 	u8 bits_per_word;
314 	int ret;
315 
316 	reg_base = mpc8xxx_spi->reg_base;
317 	bits_per_word = spi->bits_per_word;
318 	if (t->bits_per_word)
319 		bits_per_word = t->bits_per_word;
320 
321 	if (bits_per_word > 8) {
322 		/* invalid length? */
323 		if (len & 1)
324 			return -EINVAL;
325 		len /= 2;
326 	}
327 	if (bits_per_word > 16) {
328 		/* invalid length? */
329 		if (len & 1)
330 			return -EINVAL;
331 		len /= 2;
332 	}
333 
334 	mpc8xxx_spi->tx = t->tx_buf;
335 	mpc8xxx_spi->rx = t->rx_buf;
336 
337 	reinit_completion(&mpc8xxx_spi->done);
338 
339 	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
340 		ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped);
341 	else
342 		ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len);
343 	if (ret)
344 		return ret;
345 
346 	wait_for_completion(&mpc8xxx_spi->done);
347 
348 	/* disable rx ints */
349 	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
350 
351 	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
352 		fsl_spi_cpm_bufs_complete(mpc8xxx_spi);
353 
354 	return mpc8xxx_spi->count;
355 }
356 
357 static int fsl_spi_do_one_msg(struct spi_master *master,
358 			      struct spi_message *m)
359 {
360 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
361 	struct spi_device *spi = m->spi;
362 	struct spi_transfer *t, *first;
363 	unsigned int cs_change;
364 	const int nsecs = 50;
365 	int status, last_bpw;
366 
367 	/*
368 	 * In CPU mode, optimize large byte transfers to use larger
369 	 * bits_per_word values to reduce number of interrupts taken.
370 	 */
371 	if (!(mpc8xxx_spi->flags & SPI_CPM_MODE)) {
372 		list_for_each_entry(t, &m->transfers, transfer_list) {
373 			if (t->len < 256 || t->bits_per_word != 8)
374 				continue;
375 			if ((t->len & 3) == 0)
376 				t->bits_per_word = 32;
377 			else if ((t->len & 1) == 0)
378 				t->bits_per_word = 16;
379 		}
380 	}
381 
382 	/* Don't allow changes if CS is active */
383 	cs_change = 1;
384 	list_for_each_entry(t, &m->transfers, transfer_list) {
385 		if (cs_change)
386 			first = t;
387 		cs_change = t->cs_change;
388 		if (first->speed_hz != t->speed_hz) {
389 			dev_err(&spi->dev,
390 				"speed_hz cannot change while CS is active\n");
391 			return -EINVAL;
392 		}
393 	}
394 
395 	last_bpw = -1;
396 	cs_change = 1;
397 	status = -EINVAL;
398 	list_for_each_entry(t, &m->transfers, transfer_list) {
399 		if (cs_change || last_bpw != t->bits_per_word)
400 			status = fsl_spi_setup_transfer(spi, t);
401 		if (status < 0)
402 			break;
403 		last_bpw = t->bits_per_word;
404 
405 		if (cs_change) {
406 			fsl_spi_chipselect(spi, BITBANG_CS_ACTIVE);
407 			ndelay(nsecs);
408 		}
409 		cs_change = t->cs_change;
410 		if (t->len)
411 			status = fsl_spi_bufs(spi, t, m->is_dma_mapped);
412 		if (status) {
413 			status = -EMSGSIZE;
414 			break;
415 		}
416 		m->actual_length += t->len;
417 
418 		spi_transfer_delay_exec(t);
419 
420 		if (cs_change) {
421 			ndelay(nsecs);
422 			fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
423 			ndelay(nsecs);
424 		}
425 	}
426 
427 	m->status = status;
428 
429 	if (status || !cs_change) {
430 		ndelay(nsecs);
431 		fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
432 	}
433 
434 	fsl_spi_setup_transfer(spi, NULL);
435 	spi_finalize_current_message(master);
436 	return 0;
437 }
438 
439 static int fsl_spi_setup(struct spi_device *spi)
440 {
441 	struct mpc8xxx_spi *mpc8xxx_spi;
442 	struct fsl_spi_reg __iomem *reg_base;
443 	int retval;
444 	u32 hw_mode;
445 	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
446 
447 	if (!spi->max_speed_hz)
448 		return -EINVAL;
449 
450 	if (!cs) {
451 		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
452 		if (!cs)
453 			return -ENOMEM;
454 		spi_set_ctldata(spi, cs);
455 	}
456 	mpc8xxx_spi = spi_master_get_devdata(spi->master);
457 
458 	reg_base = mpc8xxx_spi->reg_base;
459 
460 	hw_mode = cs->hw_mode; /* Save original settings */
461 	cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
462 	/* mask out bits we are going to set */
463 	cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
464 			 | SPMODE_REV | SPMODE_LOOP);
465 
466 	if (spi->mode & SPI_CPHA)
467 		cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
468 	if (spi->mode & SPI_CPOL)
469 		cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
470 	if (!(spi->mode & SPI_LSB_FIRST))
471 		cs->hw_mode |= SPMODE_REV;
472 	if (spi->mode & SPI_LOOP)
473 		cs->hw_mode |= SPMODE_LOOP;
474 
475 	retval = fsl_spi_setup_transfer(spi, NULL);
476 	if (retval < 0) {
477 		cs->hw_mode = hw_mode; /* Restore settings */
478 		return retval;
479 	}
480 
481 	/* Initialize chipselect - might be active for SPI_CS_HIGH mode */
482 	fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
483 
484 	return 0;
485 }
486 
487 static void fsl_spi_cleanup(struct spi_device *spi)
488 {
489 	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
490 
491 	kfree(cs);
492 	spi_set_ctldata(spi, NULL);
493 }
494 
495 static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
496 {
497 	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
498 
499 	/* We need handle RX first */
500 	if (events & SPIE_NE) {
501 		u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
502 
503 		if (mspi->rx)
504 			mspi->get_rx(rx_data, mspi);
505 	}
506 
507 	if ((events & SPIE_NF) == 0)
508 		/* spin until TX is done */
509 		while (((events =
510 			mpc8xxx_spi_read_reg(&reg_base->event)) &
511 						SPIE_NF) == 0)
512 			cpu_relax();
513 
514 	/* Clear the events */
515 	mpc8xxx_spi_write_reg(&reg_base->event, events);
516 
517 	mspi->count -= 1;
518 	if (mspi->count) {
519 		u32 word = mspi->get_tx(mspi);
520 
521 		mpc8xxx_spi_write_reg(&reg_base->transmit, word);
522 	} else {
523 		complete(&mspi->done);
524 	}
525 }
526 
527 static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
528 {
529 	struct mpc8xxx_spi *mspi = context_data;
530 	irqreturn_t ret = IRQ_NONE;
531 	u32 events;
532 	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
533 
534 	/* Get interrupt events(tx/rx) */
535 	events = mpc8xxx_spi_read_reg(&reg_base->event);
536 	if (events)
537 		ret = IRQ_HANDLED;
538 
539 	dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
540 
541 	if (mspi->flags & SPI_CPM_MODE)
542 		fsl_spi_cpm_irq(mspi, events);
543 	else
544 		fsl_spi_cpu_irq(mspi, events);
545 
546 	return ret;
547 }
548 
549 static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on)
550 {
551 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
552 	struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base;
553 	u32 slvsel;
554 	u16 cs = spi->chip_select;
555 
556 	if (spi->cs_gpiod) {
557 		gpiod_set_value(spi->cs_gpiod, on);
558 	} else if (cs < mpc8xxx_spi->native_chipselects) {
559 		slvsel = mpc8xxx_spi_read_reg(&reg_base->slvsel);
560 		slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs));
561 		mpc8xxx_spi_write_reg(&reg_base->slvsel, slvsel);
562 	}
563 }
564 
565 static void fsl_spi_grlib_probe(struct device *dev)
566 {
567 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
568 	struct spi_master *master = dev_get_drvdata(dev);
569 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
570 	struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base;
571 	int mbits;
572 	u32 capabilities;
573 
574 	capabilities = mpc8xxx_spi_read_reg(&reg_base->cap);
575 
576 	mpc8xxx_spi->set_shifts = fsl_spi_grlib_set_shifts;
577 	mbits = SPCAP_MAXWLEN(capabilities);
578 	if (mbits)
579 		mpc8xxx_spi->max_bits_per_word = mbits + 1;
580 
581 	mpc8xxx_spi->native_chipselects = 0;
582 	if (SPCAP_SSEN(capabilities)) {
583 		mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities);
584 		mpc8xxx_spi_write_reg(&reg_base->slvsel, 0xffffffff);
585 	}
586 	master->num_chipselect = mpc8xxx_spi->native_chipselects;
587 	pdata->cs_control = fsl_spi_grlib_cs_control;
588 }
589 
590 static struct spi_master *fsl_spi_probe(struct device *dev,
591 		struct resource *mem, unsigned int irq)
592 {
593 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
594 	struct spi_master *master;
595 	struct mpc8xxx_spi *mpc8xxx_spi;
596 	struct fsl_spi_reg __iomem *reg_base;
597 	u32 regval;
598 	int ret = 0;
599 
600 	master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
601 	if (master == NULL) {
602 		ret = -ENOMEM;
603 		goto err;
604 	}
605 
606 	dev_set_drvdata(dev, master);
607 
608 	mpc8xxx_spi_probe(dev, mem, irq);
609 
610 	master->setup = fsl_spi_setup;
611 	master->cleanup = fsl_spi_cleanup;
612 	master->transfer_one_message = fsl_spi_do_one_msg;
613 	master->use_gpio_descriptors = true;
614 
615 	mpc8xxx_spi = spi_master_get_devdata(master);
616 	mpc8xxx_spi->max_bits_per_word = 32;
617 	mpc8xxx_spi->type = fsl_spi_get_type(dev);
618 
619 	ret = fsl_spi_cpm_init(mpc8xxx_spi);
620 	if (ret)
621 		goto err_cpm_init;
622 
623 	mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem);
624 	if (IS_ERR(mpc8xxx_spi->reg_base)) {
625 		ret = PTR_ERR(mpc8xxx_spi->reg_base);
626 		goto err_probe;
627 	}
628 
629 	if (mpc8xxx_spi->type == TYPE_GRLIB)
630 		fsl_spi_grlib_probe(dev);
631 
632 	master->bits_per_word_mask =
633 		(SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32)) &
634 		SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word);
635 
636 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
637 		mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts;
638 
639 	if (mpc8xxx_spi->set_shifts)
640 		/* 8 bits per word and MSB first */
641 		mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift,
642 					&mpc8xxx_spi->tx_shift, 8, 1);
643 
644 	/* Register for SPI Interrupt */
645 	ret = devm_request_irq(dev, mpc8xxx_spi->irq, fsl_spi_irq,
646 			       0, "fsl_spi", mpc8xxx_spi);
647 
648 	if (ret != 0)
649 		goto err_probe;
650 
651 	reg_base = mpc8xxx_spi->reg_base;
652 
653 	/* SPI controller initializations */
654 	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
655 	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
656 	mpc8xxx_spi_write_reg(&reg_base->command, 0);
657 	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
658 
659 	/* Enable SPI interface */
660 	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
661 	if (mpc8xxx_spi->max_bits_per_word < 8) {
662 		regval &= ~SPMODE_LEN(0xF);
663 		regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1);
664 	}
665 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
666 		regval |= SPMODE_OP;
667 
668 	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
669 
670 	ret = devm_spi_register_master(dev, master);
671 	if (ret < 0)
672 		goto err_probe;
673 
674 	dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
675 		 mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
676 
677 	return master;
678 
679 err_probe:
680 	fsl_spi_cpm_free(mpc8xxx_spi);
681 err_cpm_init:
682 	spi_master_put(master);
683 err:
684 	return ERR_PTR(ret);
685 }
686 
687 static void fsl_spi_cs_control(struct spi_device *spi, bool on)
688 {
689 	if (spi->cs_gpiod) {
690 		gpiod_set_value(spi->cs_gpiod, on);
691 	} else {
692 		struct device *dev = spi->dev.parent->parent;
693 		struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
694 		struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
695 
696 		if (WARN_ON_ONCE(!pinfo->immr_spi_cs))
697 			return;
698 		iowrite32be(on ? 0 : SPI_BOOT_SEL_BIT, pinfo->immr_spi_cs);
699 	}
700 }
701 
702 static int of_fsl_spi_probe(struct platform_device *ofdev)
703 {
704 	struct device *dev = &ofdev->dev;
705 	struct device_node *np = ofdev->dev.of_node;
706 	struct spi_master *master;
707 	struct resource mem;
708 	int irq, type;
709 	int ret;
710 
711 	ret = of_mpc8xxx_spi_probe(ofdev);
712 	if (ret)
713 		return ret;
714 
715 	type = fsl_spi_get_type(&ofdev->dev);
716 	if (type == TYPE_FSL) {
717 		struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
718 		bool spisel_boot = false;
719 #if IS_ENABLED(CONFIG_FSL_SOC)
720 		struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
721 
722 		spisel_boot = of_property_read_bool(np, "fsl,spisel_boot");
723 		if (spisel_boot) {
724 			pinfo->immr_spi_cs = ioremap(get_immrbase() + IMMR_SPI_CS_OFFSET, 4);
725 			if (!pinfo->immr_spi_cs)
726 				return -ENOMEM;
727 		}
728 #endif
729 		/*
730 		 * Handle the case where we have one hardwired (always selected)
731 		 * device on the first "chipselect". Else we let the core code
732 		 * handle any GPIOs or native chip selects and assign the
733 		 * appropriate callback for dealing with the CS lines. This isn't
734 		 * supported on the GRLIB variant.
735 		 */
736 		ret = gpiod_count(dev, "cs");
737 		if (ret < 0)
738 			ret = 0;
739 		if (ret == 0 && !spisel_boot) {
740 			pdata->max_chipselect = 1;
741 		} else {
742 			pdata->max_chipselect = ret + spisel_boot;
743 			pdata->cs_control = fsl_spi_cs_control;
744 		}
745 	}
746 
747 	ret = of_address_to_resource(np, 0, &mem);
748 	if (ret)
749 		return ret;
750 
751 	irq = platform_get_irq(ofdev, 0);
752 	if (irq < 0)
753 		return irq;
754 
755 	master = fsl_spi_probe(dev, &mem, irq);
756 
757 	return PTR_ERR_OR_ZERO(master);
758 }
759 
760 static int of_fsl_spi_remove(struct platform_device *ofdev)
761 {
762 	struct spi_master *master = platform_get_drvdata(ofdev);
763 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
764 
765 	fsl_spi_cpm_free(mpc8xxx_spi);
766 	return 0;
767 }
768 
769 static struct platform_driver of_fsl_spi_driver = {
770 	.driver = {
771 		.name = "fsl_spi",
772 		.of_match_table = of_fsl_spi_match,
773 	},
774 	.probe		= of_fsl_spi_probe,
775 	.remove		= of_fsl_spi_remove,
776 };
777 
778 #ifdef CONFIG_MPC832x_RDB
779 /*
780  * XXX XXX XXX
781  * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
782  * only. The driver should go away soon, since newer MPC8323E-RDB's device
783  * tree can work with OpenFirmware driver. But for now we support old trees
784  * as well.
785  */
786 static int plat_mpc8xxx_spi_probe(struct platform_device *pdev)
787 {
788 	struct resource *mem;
789 	int irq;
790 	struct spi_master *master;
791 
792 	if (!dev_get_platdata(&pdev->dev))
793 		return -EINVAL;
794 
795 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
796 	if (!mem)
797 		return -EINVAL;
798 
799 	irq = platform_get_irq(pdev, 0);
800 	if (irq <= 0)
801 		return -EINVAL;
802 
803 	master = fsl_spi_probe(&pdev->dev, mem, irq);
804 	return PTR_ERR_OR_ZERO(master);
805 }
806 
807 static int plat_mpc8xxx_spi_remove(struct platform_device *pdev)
808 {
809 	struct spi_master *master = platform_get_drvdata(pdev);
810 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
811 
812 	fsl_spi_cpm_free(mpc8xxx_spi);
813 
814 	return 0;
815 }
816 
817 MODULE_ALIAS("platform:mpc8xxx_spi");
818 static struct platform_driver mpc8xxx_spi_driver = {
819 	.probe = plat_mpc8xxx_spi_probe,
820 	.remove = plat_mpc8xxx_spi_remove,
821 	.driver = {
822 		.name = "mpc8xxx_spi",
823 	},
824 };
825 
826 static bool legacy_driver_failed;
827 
828 static void __init legacy_driver_register(void)
829 {
830 	legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
831 }
832 
833 static void __exit legacy_driver_unregister(void)
834 {
835 	if (legacy_driver_failed)
836 		return;
837 	platform_driver_unregister(&mpc8xxx_spi_driver);
838 }
839 #else
840 static void __init legacy_driver_register(void) {}
841 static void __exit legacy_driver_unregister(void) {}
842 #endif /* CONFIG_MPC832x_RDB */
843 
844 static int __init fsl_spi_init(void)
845 {
846 	legacy_driver_register();
847 	return platform_driver_register(&of_fsl_spi_driver);
848 }
849 module_init(fsl_spi_init);
850 
851 static void __exit fsl_spi_exit(void)
852 {
853 	platform_driver_unregister(&of_fsl_spi_driver);
854 	legacy_driver_unregister();
855 }
856 module_exit(fsl_spi_exit);
857 
858 MODULE_AUTHOR("Kumar Gala");
859 MODULE_DESCRIPTION("Simple Freescale SPI Driver");
860 MODULE_LICENSE("GPL");
861