xref: /openbmc/linux/drivers/spi/spi-fsl-spi.c (revision f21e49be)
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 	bool initial_setup = false;
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 		initial_setup = true;
457 	}
458 	mpc8xxx_spi = spi_master_get_devdata(spi->master);
459 
460 	reg_base = mpc8xxx_spi->reg_base;
461 
462 	hw_mode = cs->hw_mode; /* Save original settings */
463 	cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
464 	/* mask out bits we are going to set */
465 	cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
466 			 | SPMODE_REV | SPMODE_LOOP);
467 
468 	if (spi->mode & SPI_CPHA)
469 		cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
470 	if (spi->mode & SPI_CPOL)
471 		cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
472 	if (!(spi->mode & SPI_LSB_FIRST))
473 		cs->hw_mode |= SPMODE_REV;
474 	if (spi->mode & SPI_LOOP)
475 		cs->hw_mode |= SPMODE_LOOP;
476 
477 	retval = fsl_spi_setup_transfer(spi, NULL);
478 	if (retval < 0) {
479 		cs->hw_mode = hw_mode; /* Restore settings */
480 		if (initial_setup)
481 			kfree(cs);
482 		return retval;
483 	}
484 
485 	/* Initialize chipselect - might be active for SPI_CS_HIGH mode */
486 	fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
487 
488 	return 0;
489 }
490 
491 static void fsl_spi_cleanup(struct spi_device *spi)
492 {
493 	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
494 
495 	kfree(cs);
496 	spi_set_ctldata(spi, NULL);
497 }
498 
499 static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
500 {
501 	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
502 
503 	/* We need handle RX first */
504 	if (events & SPIE_NE) {
505 		u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
506 
507 		if (mspi->rx)
508 			mspi->get_rx(rx_data, mspi);
509 	}
510 
511 	if ((events & SPIE_NF) == 0)
512 		/* spin until TX is done */
513 		while (((events =
514 			mpc8xxx_spi_read_reg(&reg_base->event)) &
515 						SPIE_NF) == 0)
516 			cpu_relax();
517 
518 	/* Clear the events */
519 	mpc8xxx_spi_write_reg(&reg_base->event, events);
520 
521 	mspi->count -= 1;
522 	if (mspi->count) {
523 		u32 word = mspi->get_tx(mspi);
524 
525 		mpc8xxx_spi_write_reg(&reg_base->transmit, word);
526 	} else {
527 		complete(&mspi->done);
528 	}
529 }
530 
531 static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
532 {
533 	struct mpc8xxx_spi *mspi = context_data;
534 	irqreturn_t ret = IRQ_NONE;
535 	u32 events;
536 	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
537 
538 	/* Get interrupt events(tx/rx) */
539 	events = mpc8xxx_spi_read_reg(&reg_base->event);
540 	if (events)
541 		ret = IRQ_HANDLED;
542 
543 	dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
544 
545 	if (mspi->flags & SPI_CPM_MODE)
546 		fsl_spi_cpm_irq(mspi, events);
547 	else
548 		fsl_spi_cpu_irq(mspi, events);
549 
550 	return ret;
551 }
552 
553 static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on)
554 {
555 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
556 	struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base;
557 	u32 slvsel;
558 	u16 cs = spi->chip_select;
559 
560 	if (spi->cs_gpiod) {
561 		gpiod_set_value(spi->cs_gpiod, on);
562 	} else if (cs < mpc8xxx_spi->native_chipselects) {
563 		slvsel = mpc8xxx_spi_read_reg(&reg_base->slvsel);
564 		slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs));
565 		mpc8xxx_spi_write_reg(&reg_base->slvsel, slvsel);
566 	}
567 }
568 
569 static void fsl_spi_grlib_probe(struct device *dev)
570 {
571 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
572 	struct spi_master *master = dev_get_drvdata(dev);
573 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
574 	struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base;
575 	int mbits;
576 	u32 capabilities;
577 
578 	capabilities = mpc8xxx_spi_read_reg(&reg_base->cap);
579 
580 	mpc8xxx_spi->set_shifts = fsl_spi_grlib_set_shifts;
581 	mbits = SPCAP_MAXWLEN(capabilities);
582 	if (mbits)
583 		mpc8xxx_spi->max_bits_per_word = mbits + 1;
584 
585 	mpc8xxx_spi->native_chipselects = 0;
586 	if (SPCAP_SSEN(capabilities)) {
587 		mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities);
588 		mpc8xxx_spi_write_reg(&reg_base->slvsel, 0xffffffff);
589 	}
590 	master->num_chipselect = mpc8xxx_spi->native_chipselects;
591 	pdata->cs_control = fsl_spi_grlib_cs_control;
592 }
593 
594 static struct spi_master *fsl_spi_probe(struct device *dev,
595 		struct resource *mem, unsigned int irq)
596 {
597 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
598 	struct spi_master *master;
599 	struct mpc8xxx_spi *mpc8xxx_spi;
600 	struct fsl_spi_reg __iomem *reg_base;
601 	u32 regval;
602 	int ret = 0;
603 
604 	master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
605 	if (master == NULL) {
606 		ret = -ENOMEM;
607 		goto err;
608 	}
609 
610 	dev_set_drvdata(dev, master);
611 
612 	mpc8xxx_spi_probe(dev, mem, irq);
613 
614 	master->setup = fsl_spi_setup;
615 	master->cleanup = fsl_spi_cleanup;
616 	master->transfer_one_message = fsl_spi_do_one_msg;
617 	master->use_gpio_descriptors = true;
618 
619 	mpc8xxx_spi = spi_master_get_devdata(master);
620 	mpc8xxx_spi->max_bits_per_word = 32;
621 	mpc8xxx_spi->type = fsl_spi_get_type(dev);
622 
623 	ret = fsl_spi_cpm_init(mpc8xxx_spi);
624 	if (ret)
625 		goto err_cpm_init;
626 
627 	mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem);
628 	if (IS_ERR(mpc8xxx_spi->reg_base)) {
629 		ret = PTR_ERR(mpc8xxx_spi->reg_base);
630 		goto err_probe;
631 	}
632 
633 	if (mpc8xxx_spi->type == TYPE_GRLIB)
634 		fsl_spi_grlib_probe(dev);
635 
636 	master->bits_per_word_mask =
637 		(SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32)) &
638 		SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word);
639 
640 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
641 		mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts;
642 
643 	if (mpc8xxx_spi->set_shifts)
644 		/* 8 bits per word and MSB first */
645 		mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift,
646 					&mpc8xxx_spi->tx_shift, 8, 1);
647 
648 	/* Register for SPI Interrupt */
649 	ret = devm_request_irq(dev, mpc8xxx_spi->irq, fsl_spi_irq,
650 			       0, "fsl_spi", mpc8xxx_spi);
651 
652 	if (ret != 0)
653 		goto err_probe;
654 
655 	reg_base = mpc8xxx_spi->reg_base;
656 
657 	/* SPI controller initializations */
658 	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
659 	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
660 	mpc8xxx_spi_write_reg(&reg_base->command, 0);
661 	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
662 
663 	/* Enable SPI interface */
664 	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
665 	if (mpc8xxx_spi->max_bits_per_word < 8) {
666 		regval &= ~SPMODE_LEN(0xF);
667 		regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1);
668 	}
669 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
670 		regval |= SPMODE_OP;
671 
672 	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
673 
674 	ret = devm_spi_register_master(dev, master);
675 	if (ret < 0)
676 		goto err_probe;
677 
678 	dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
679 		 mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
680 
681 	return master;
682 
683 err_probe:
684 	fsl_spi_cpm_free(mpc8xxx_spi);
685 err_cpm_init:
686 	spi_master_put(master);
687 err:
688 	return ERR_PTR(ret);
689 }
690 
691 static void fsl_spi_cs_control(struct spi_device *spi, bool on)
692 {
693 	if (spi->cs_gpiod) {
694 		gpiod_set_value(spi->cs_gpiod, on);
695 	} else {
696 		struct device *dev = spi->dev.parent->parent;
697 		struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
698 		struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
699 
700 		if (WARN_ON_ONCE(!pinfo->immr_spi_cs))
701 			return;
702 		iowrite32be(on ? 0 : SPI_BOOT_SEL_BIT, pinfo->immr_spi_cs);
703 	}
704 }
705 
706 static int of_fsl_spi_probe(struct platform_device *ofdev)
707 {
708 	struct device *dev = &ofdev->dev;
709 	struct device_node *np = ofdev->dev.of_node;
710 	struct spi_master *master;
711 	struct resource mem;
712 	int irq, type;
713 	int ret;
714 	bool spisel_boot = false;
715 #if IS_ENABLED(CONFIG_FSL_SOC)
716 	struct mpc8xxx_spi_probe_info *pinfo = NULL;
717 #endif
718 
719 
720 	ret = of_mpc8xxx_spi_probe(ofdev);
721 	if (ret)
722 		return ret;
723 
724 	type = fsl_spi_get_type(&ofdev->dev);
725 	if (type == TYPE_FSL) {
726 		struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
727 #if IS_ENABLED(CONFIG_FSL_SOC)
728 		pinfo = to_of_pinfo(pdata);
729 
730 		spisel_boot = of_property_read_bool(np, "fsl,spisel_boot");
731 		if (spisel_boot) {
732 			pinfo->immr_spi_cs = ioremap(get_immrbase() + IMMR_SPI_CS_OFFSET, 4);
733 			if (!pinfo->immr_spi_cs)
734 				return -ENOMEM;
735 		}
736 #endif
737 		/*
738 		 * Handle the case where we have one hardwired (always selected)
739 		 * device on the first "chipselect". Else we let the core code
740 		 * handle any GPIOs or native chip selects and assign the
741 		 * appropriate callback for dealing with the CS lines. This isn't
742 		 * supported on the GRLIB variant.
743 		 */
744 		ret = gpiod_count(dev, "cs");
745 		if (ret < 0)
746 			ret = 0;
747 		if (ret == 0 && !spisel_boot) {
748 			pdata->max_chipselect = 1;
749 		} else {
750 			pdata->max_chipselect = ret + spisel_boot;
751 			pdata->cs_control = fsl_spi_cs_control;
752 		}
753 	}
754 
755 	ret = of_address_to_resource(np, 0, &mem);
756 	if (ret)
757 		goto unmap_out;
758 
759 	irq = platform_get_irq(ofdev, 0);
760 	if (irq < 0) {
761 		ret = irq;
762 		goto unmap_out;
763 	}
764 
765 	master = fsl_spi_probe(dev, &mem, irq);
766 
767 	return PTR_ERR_OR_ZERO(master);
768 
769 unmap_out:
770 #if IS_ENABLED(CONFIG_FSL_SOC)
771 	if (spisel_boot)
772 		iounmap(pinfo->immr_spi_cs);
773 #endif
774 	return ret;
775 }
776 
777 static int of_fsl_spi_remove(struct platform_device *ofdev)
778 {
779 	struct spi_master *master = platform_get_drvdata(ofdev);
780 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
781 
782 	fsl_spi_cpm_free(mpc8xxx_spi);
783 	return 0;
784 }
785 
786 static struct platform_driver of_fsl_spi_driver = {
787 	.driver = {
788 		.name = "fsl_spi",
789 		.of_match_table = of_fsl_spi_match,
790 	},
791 	.probe		= of_fsl_spi_probe,
792 	.remove		= of_fsl_spi_remove,
793 };
794 
795 #ifdef CONFIG_MPC832x_RDB
796 /*
797  * XXX XXX XXX
798  * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
799  * only. The driver should go away soon, since newer MPC8323E-RDB's device
800  * tree can work with OpenFirmware driver. But for now we support old trees
801  * as well.
802  */
803 static int plat_mpc8xxx_spi_probe(struct platform_device *pdev)
804 {
805 	struct resource *mem;
806 	int irq;
807 	struct spi_master *master;
808 
809 	if (!dev_get_platdata(&pdev->dev))
810 		return -EINVAL;
811 
812 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
813 	if (!mem)
814 		return -EINVAL;
815 
816 	irq = platform_get_irq(pdev, 0);
817 	if (irq <= 0)
818 		return -EINVAL;
819 
820 	master = fsl_spi_probe(&pdev->dev, mem, irq);
821 	return PTR_ERR_OR_ZERO(master);
822 }
823 
824 static int plat_mpc8xxx_spi_remove(struct platform_device *pdev)
825 {
826 	struct spi_master *master = platform_get_drvdata(pdev);
827 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
828 
829 	fsl_spi_cpm_free(mpc8xxx_spi);
830 
831 	return 0;
832 }
833 
834 MODULE_ALIAS("platform:mpc8xxx_spi");
835 static struct platform_driver mpc8xxx_spi_driver = {
836 	.probe = plat_mpc8xxx_spi_probe,
837 	.remove = plat_mpc8xxx_spi_remove,
838 	.driver = {
839 		.name = "mpc8xxx_spi",
840 	},
841 };
842 
843 static bool legacy_driver_failed;
844 
845 static void __init legacy_driver_register(void)
846 {
847 	legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
848 }
849 
850 static void __exit legacy_driver_unregister(void)
851 {
852 	if (legacy_driver_failed)
853 		return;
854 	platform_driver_unregister(&mpc8xxx_spi_driver);
855 }
856 #else
857 static void __init legacy_driver_register(void) {}
858 static void __exit legacy_driver_unregister(void) {}
859 #endif /* CONFIG_MPC832x_RDB */
860 
861 static int __init fsl_spi_init(void)
862 {
863 	legacy_driver_register();
864 	return platform_driver_register(&of_fsl_spi_driver);
865 }
866 module_init(fsl_spi_init);
867 
868 static void __exit fsl_spi_exit(void)
869 {
870 	platform_driver_unregister(&of_fsl_spi_driver);
871 	legacy_driver_unregister();
872 }
873 module_exit(fsl_spi_exit);
874 
875 MODULE_AUTHOR("Kumar Gala");
876 MODULE_DESCRIPTION("Simple Freescale SPI Driver");
877 MODULE_LICENSE("GPL");
878