xref: /linux/drivers/spi/spi-fsl-spi.c (revision f898c16a0624e7f2dcb0b1cda6916c9be6489197)
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_controller_get_devdata(spi->controller);
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_qe_cpu_set_shifts(u32 *rx_shift, u32 *tx_shift,
115 				      int bits_per_word, int msb_first)
116 {
117 	*rx_shift = 0;
118 	*tx_shift = 0;
119 	if (msb_first) {
120 		if (bits_per_word <= 8) {
121 			*rx_shift = 16;
122 			*tx_shift = 24;
123 		} else if (bits_per_word <= 16) {
124 			*rx_shift = 16;
125 			*tx_shift = 16;
126 		}
127 	} else {
128 		if (bits_per_word <= 8)
129 			*rx_shift = 8;
130 	}
131 }
132 
133 static void fsl_spi_grlib_set_shifts(u32 *rx_shift, u32 *tx_shift,
134 				     int bits_per_word, int msb_first)
135 {
136 	*rx_shift = 0;
137 	*tx_shift = 0;
138 	if (bits_per_word <= 16) {
139 		if (msb_first) {
140 			*rx_shift = 16; /* LSB in bit 16 */
141 			*tx_shift = 32 - bits_per_word; /* MSB in bit 31 */
142 		} else {
143 			*rx_shift = 16 - bits_per_word; /* MSB in bit 15 */
144 		}
145 	}
146 }
147 
148 static void mspi_apply_cpu_mode_quirks(struct spi_mpc8xxx_cs *cs,
149 				       struct spi_device *spi,
150 				       struct mpc8xxx_spi *mpc8xxx_spi,
151 				       int bits_per_word)
152 {
153 	cs->rx_shift = 0;
154 	cs->tx_shift = 0;
155 	if (bits_per_word <= 8) {
156 		cs->get_rx = mpc8xxx_spi_rx_buf_u8;
157 		cs->get_tx = mpc8xxx_spi_tx_buf_u8;
158 	} else if (bits_per_word <= 16) {
159 		cs->get_rx = mpc8xxx_spi_rx_buf_u16;
160 		cs->get_tx = mpc8xxx_spi_tx_buf_u16;
161 	} else if (bits_per_word <= 32) {
162 		cs->get_rx = mpc8xxx_spi_rx_buf_u32;
163 		cs->get_tx = mpc8xxx_spi_tx_buf_u32;
164 	}
165 
166 	if (mpc8xxx_spi->set_shifts)
167 		mpc8xxx_spi->set_shifts(&cs->rx_shift, &cs->tx_shift,
168 					bits_per_word,
169 					!(spi->mode & SPI_LSB_FIRST));
170 
171 	mpc8xxx_spi->rx_shift = cs->rx_shift;
172 	mpc8xxx_spi->tx_shift = cs->tx_shift;
173 	mpc8xxx_spi->get_rx = cs->get_rx;
174 	mpc8xxx_spi->get_tx = cs->get_tx;
175 }
176 
177 static int fsl_spi_setup_transfer(struct spi_device *spi,
178 					struct spi_transfer *t)
179 {
180 	struct mpc8xxx_spi *mpc8xxx_spi;
181 	int bits_per_word = 0;
182 	u8 pm;
183 	u32 hz = 0;
184 	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
185 
186 	mpc8xxx_spi = spi_controller_get_devdata(spi->controller);
187 
188 	if (t) {
189 		bits_per_word = t->bits_per_word;
190 		hz = t->speed_hz;
191 	}
192 
193 	/* spi_transfer level calls that work per-word */
194 	if (!bits_per_word)
195 		bits_per_word = spi->bits_per_word;
196 
197 	if (!hz)
198 		hz = spi->max_speed_hz;
199 
200 	if (!(mpc8xxx_spi->flags & SPI_CPM_MODE))
201 		mspi_apply_cpu_mode_quirks(cs, spi, mpc8xxx_spi, bits_per_word);
202 
203 	if (bits_per_word == 32)
204 		bits_per_word = 0;
205 	else
206 		bits_per_word = bits_per_word - 1;
207 
208 	/* mask out bits we are going to set */
209 	cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16
210 				  | SPMODE_PM(0xF));
211 
212 	cs->hw_mode |= SPMODE_LEN(bits_per_word);
213 
214 	if ((mpc8xxx_spi->spibrg / hz) > 64) {
215 		cs->hw_mode |= SPMODE_DIV16;
216 		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
217 		WARN_ONCE(pm > 16,
218 			  "%s: Requested speed is too low: %d Hz. Will use %d Hz instead.\n",
219 			  dev_name(&spi->dev), hz, mpc8xxx_spi->spibrg / 1024);
220 		if (pm > 16)
221 			pm = 16;
222 	} else {
223 		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
224 	}
225 	if (pm)
226 		pm--;
227 
228 	cs->hw_mode |= SPMODE_PM(pm);
229 
230 	fsl_spi_change_mode(spi);
231 	return 0;
232 }
233 
234 static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi,
235 				struct spi_transfer *t, unsigned int len)
236 {
237 	u32 word;
238 	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
239 
240 	mspi->count = len;
241 
242 	/* enable rx ints */
243 	mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
244 
245 	/* transmit word */
246 	word = mspi->get_tx(mspi);
247 	mpc8xxx_spi_write_reg(&reg_base->transmit, word);
248 
249 	return 0;
250 }
251 
252 static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t)
253 {
254 	struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(spi->controller);
255 	struct fsl_spi_reg __iomem *reg_base;
256 	unsigned int len = t->len;
257 	u8 bits_per_word;
258 	int ret;
259 
260 	reg_base = mpc8xxx_spi->reg_base;
261 	bits_per_word = spi->bits_per_word;
262 	if (t->bits_per_word)
263 		bits_per_word = t->bits_per_word;
264 
265 	if (bits_per_word > 8)
266 		len /= 2;
267 	if (bits_per_word > 16)
268 		len /= 2;
269 
270 	mpc8xxx_spi->tx = t->tx_buf;
271 	mpc8xxx_spi->rx = t->rx_buf;
272 
273 	reinit_completion(&mpc8xxx_spi->done);
274 
275 	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
276 		ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t);
277 	else
278 		ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len);
279 	if (ret)
280 		return ret;
281 
282 	wait_for_completion(&mpc8xxx_spi->done);
283 
284 	/* disable rx ints */
285 	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
286 
287 	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
288 		fsl_spi_cpm_bufs_complete(mpc8xxx_spi);
289 
290 	return mpc8xxx_spi->count;
291 }
292 
293 static int fsl_spi_prepare_message(struct spi_controller *ctlr,
294 				   struct spi_message *m)
295 {
296 	struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(ctlr);
297 	struct spi_transfer *t;
298 	struct spi_transfer *first;
299 
300 	first = list_first_entry(&m->transfers, struct spi_transfer,
301 				 transfer_list);
302 
303 	/*
304 	 * In CPU mode, optimize large byte transfers to use larger
305 	 * bits_per_word values to reduce number of interrupts taken.
306 	 *
307 	 * Some glitches can appear on the SPI clock when the mode changes.
308 	 * Check that there is no speed change during the transfer and set it up
309 	 * now to change the mode without having a chip-select asserted.
310 	 */
311 	list_for_each_entry(t, &m->transfers, transfer_list) {
312 		if (t->speed_hz != first->speed_hz) {
313 			dev_err(&m->spi->dev,
314 				"speed_hz cannot change during message.\n");
315 			return -EINVAL;
316 		}
317 		if (!(mpc8xxx_spi->flags & SPI_CPM_MODE)) {
318 			if (t->len < 256 || t->bits_per_word != 8)
319 				continue;
320 			if ((t->len & 3) == 0)
321 				t->bits_per_word = 32;
322 			else if ((t->len & 1) == 0)
323 				t->bits_per_word = 16;
324 		} else {
325 			/*
326 			 * CPM/QE uses Little Endian for words > 8
327 			 * so transform 16 and 32 bits words into 8 bits
328 			 * Unfortnatly that doesn't work for LSB so
329 			 * reject these for now
330 			 * Note: 32 bits word, LSB works iff
331 			 * tfcr/rfcr is set to CPMFCR_GBL
332 			 */
333 			if (m->spi->mode & SPI_LSB_FIRST && t->bits_per_word > 8)
334 				return -EINVAL;
335 			if (t->bits_per_word == 16 || t->bits_per_word == 32)
336 				t->bits_per_word = 8; /* pretend its 8 bits */
337 			if (t->bits_per_word == 8 && t->len >= 256 &&
338 			    (mpc8xxx_spi->flags & SPI_CPM1))
339 				t->bits_per_word = 16;
340 		}
341 	}
342 	return fsl_spi_setup_transfer(m->spi, first);
343 }
344 
345 static int fsl_spi_transfer_one(struct spi_controller *controller,
346 				struct spi_device *spi,
347 				struct spi_transfer *t)
348 {
349 	int status;
350 
351 	status = fsl_spi_setup_transfer(spi, t);
352 	if (status < 0)
353 		return status;
354 	if (t->len)
355 		status = fsl_spi_bufs(spi, t);
356 	if (status > 0)
357 		return -EMSGSIZE;
358 
359 	return status;
360 }
361 
362 static int fsl_spi_unprepare_message(struct spi_controller *controller,
363 				     struct spi_message *msg)
364 {
365 	return fsl_spi_setup_transfer(msg->spi, NULL);
366 }
367 
368 static int fsl_spi_setup(struct spi_device *spi)
369 {
370 	struct mpc8xxx_spi *mpc8xxx_spi;
371 	struct fsl_spi_reg __iomem *reg_base;
372 	bool initial_setup = false;
373 	int retval;
374 	u32 hw_mode;
375 	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
376 
377 	if (!spi->max_speed_hz)
378 		return -EINVAL;
379 
380 	if (!cs) {
381 		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
382 		if (!cs)
383 			return -ENOMEM;
384 		spi_set_ctldata(spi, cs);
385 		initial_setup = true;
386 	}
387 	mpc8xxx_spi = spi_controller_get_devdata(spi->controller);
388 
389 	reg_base = mpc8xxx_spi->reg_base;
390 
391 	hw_mode = cs->hw_mode; /* Save original settings */
392 	cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
393 	/* mask out bits we are going to set */
394 	cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
395 			 | SPMODE_REV | SPMODE_LOOP);
396 
397 	if (spi->mode & SPI_CPHA)
398 		cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
399 	if (spi->mode & SPI_CPOL)
400 		cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
401 	if (!(spi->mode & SPI_LSB_FIRST))
402 		cs->hw_mode |= SPMODE_REV;
403 	if (spi->mode & SPI_LOOP)
404 		cs->hw_mode |= SPMODE_LOOP;
405 
406 	retval = fsl_spi_setup_transfer(spi, NULL);
407 	if (retval < 0) {
408 		cs->hw_mode = hw_mode; /* Restore settings */
409 		if (initial_setup)
410 			kfree(cs);
411 		return retval;
412 	}
413 
414 	return 0;
415 }
416 
417 static void fsl_spi_cleanup(struct spi_device *spi)
418 {
419 	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
420 
421 	kfree(cs);
422 	spi_set_ctldata(spi, NULL);
423 }
424 
425 static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
426 {
427 	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
428 
429 	/* We need handle RX first */
430 	if (events & SPIE_NE) {
431 		u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
432 
433 		if (mspi->rx)
434 			mspi->get_rx(rx_data, mspi);
435 	}
436 
437 	if ((events & SPIE_NF) == 0)
438 		/* spin until TX is done */
439 		while (((events =
440 			mpc8xxx_spi_read_reg(&reg_base->event)) &
441 						SPIE_NF) == 0)
442 			cpu_relax();
443 
444 	/* Clear the events */
445 	mpc8xxx_spi_write_reg(&reg_base->event, events);
446 
447 	mspi->count -= 1;
448 	if (mspi->count) {
449 		u32 word = mspi->get_tx(mspi);
450 
451 		mpc8xxx_spi_write_reg(&reg_base->transmit, word);
452 	} else {
453 		complete(&mspi->done);
454 	}
455 }
456 
457 static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
458 {
459 	struct mpc8xxx_spi *mspi = context_data;
460 	irqreturn_t ret = IRQ_NONE;
461 	u32 events;
462 	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
463 
464 	/* Get interrupt events(tx/rx) */
465 	events = mpc8xxx_spi_read_reg(&reg_base->event);
466 	if (events)
467 		ret = IRQ_HANDLED;
468 
469 	dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
470 
471 	if (mspi->flags & SPI_CPM_MODE)
472 		fsl_spi_cpm_irq(mspi, events);
473 	else
474 		fsl_spi_cpu_irq(mspi, events);
475 
476 	return ret;
477 }
478 
479 static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on)
480 {
481 	struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(spi->controller);
482 	struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base;
483 	u32 slvsel;
484 	u16 cs = spi_get_chipselect(spi, 0);
485 
486 	if (cs < mpc8xxx_spi->native_chipselects) {
487 		slvsel = mpc8xxx_spi_read_reg(&reg_base->slvsel);
488 		slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs));
489 		mpc8xxx_spi_write_reg(&reg_base->slvsel, slvsel);
490 	}
491 }
492 
493 static void fsl_spi_grlib_probe(struct device *dev)
494 {
495 	struct spi_controller *host = dev_get_drvdata(dev);
496 	struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(host);
497 	struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base;
498 	int mbits;
499 	u32 capabilities;
500 
501 	capabilities = mpc8xxx_spi_read_reg(&reg_base->cap);
502 
503 	mpc8xxx_spi->set_shifts = fsl_spi_grlib_set_shifts;
504 	mbits = SPCAP_MAXWLEN(capabilities);
505 	if (mbits)
506 		mpc8xxx_spi->max_bits_per_word = mbits + 1;
507 
508 	mpc8xxx_spi->native_chipselects = 0;
509 	if (SPCAP_SSEN(capabilities)) {
510 		mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities);
511 		mpc8xxx_spi_write_reg(&reg_base->slvsel, 0xffffffff);
512 	}
513 	host->num_chipselect = mpc8xxx_spi->native_chipselects;
514 	host->set_cs = fsl_spi_grlib_cs_control;
515 }
516 
517 static void fsl_spi_cs_control(struct spi_device *spi, bool on)
518 {
519 	struct device *dev = spi->dev.parent->parent;
520 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
521 	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
522 
523 	if (WARN_ON_ONCE(!pinfo->immr_spi_cs))
524 		return;
525 	iowrite32be(on ? 0 : SPI_BOOT_SEL_BIT, pinfo->immr_spi_cs);
526 }
527 
528 static struct spi_controller *fsl_spi_probe(struct device *dev,
529 		struct resource *mem, unsigned int irq)
530 {
531 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
532 	struct spi_controller *host;
533 	struct mpc8xxx_spi *mpc8xxx_spi;
534 	struct fsl_spi_reg __iomem *reg_base;
535 	u32 regval;
536 	int ret = 0;
537 
538 	host = spi_alloc_host(dev, sizeof(struct mpc8xxx_spi));
539 	if (host == NULL) {
540 		ret = -ENOMEM;
541 		goto err;
542 	}
543 
544 	dev_set_drvdata(dev, host);
545 
546 	mpc8xxx_spi_probe(dev, mem, irq);
547 
548 	host->setup = fsl_spi_setup;
549 	host->cleanup = fsl_spi_cleanup;
550 	host->prepare_message = fsl_spi_prepare_message;
551 	host->transfer_one = fsl_spi_transfer_one;
552 	host->unprepare_message = fsl_spi_unprepare_message;
553 	host->use_gpio_descriptors = true;
554 	host->set_cs = fsl_spi_cs_control;
555 
556 	mpc8xxx_spi = spi_controller_get_devdata(host);
557 	mpc8xxx_spi->max_bits_per_word = 32;
558 	mpc8xxx_spi->type = fsl_spi_get_type(dev);
559 
560 	ret = fsl_spi_cpm_init(mpc8xxx_spi);
561 	if (ret)
562 		goto err_cpm_init;
563 
564 	mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem);
565 	if (IS_ERR(mpc8xxx_spi->reg_base)) {
566 		ret = PTR_ERR(mpc8xxx_spi->reg_base);
567 		goto err_probe;
568 	}
569 
570 	if (mpc8xxx_spi->type == TYPE_GRLIB)
571 		fsl_spi_grlib_probe(dev);
572 
573 	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
574 		host->bits_per_word_mask =
575 			(SPI_BPW_RANGE_MASK(4, 8) | SPI_BPW_MASK(16) | SPI_BPW_MASK(32));
576 	else
577 		host->bits_per_word_mask =
578 			(SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32));
579 
580 	host->bits_per_word_mask &=
581 		SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word);
582 
583 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
584 		mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts;
585 
586 	if (mpc8xxx_spi->set_shifts)
587 		/* 8 bits per word and MSB first */
588 		mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift,
589 					&mpc8xxx_spi->tx_shift, 8, 1);
590 
591 	/* Register for SPI Interrupt */
592 	ret = devm_request_irq(dev, mpc8xxx_spi->irq, fsl_spi_irq,
593 			       0, "fsl_spi", mpc8xxx_spi);
594 
595 	if (ret != 0)
596 		goto err_probe;
597 
598 	reg_base = mpc8xxx_spi->reg_base;
599 
600 	/* SPI controller initializations */
601 	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
602 	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
603 	mpc8xxx_spi_write_reg(&reg_base->command, 0);
604 	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
605 
606 	/* Enable SPI interface */
607 	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
608 	if (mpc8xxx_spi->max_bits_per_word < 8) {
609 		regval &= ~SPMODE_LEN(0xF);
610 		regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1);
611 	}
612 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
613 		regval |= SPMODE_OP;
614 
615 	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
616 
617 	ret = devm_spi_register_controller(dev, host);
618 	if (ret < 0)
619 		goto err_probe;
620 
621 	dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
622 		 mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
623 
624 	return host;
625 
626 err_probe:
627 	fsl_spi_cpm_free(mpc8xxx_spi);
628 err_cpm_init:
629 	spi_controller_put(host);
630 err:
631 	return ERR_PTR(ret);
632 }
633 
634 static int of_fsl_spi_probe(struct platform_device *ofdev)
635 {
636 	struct device *dev = &ofdev->dev;
637 	struct device_node *np = ofdev->dev.of_node;
638 	struct spi_controller *host;
639 	struct resource mem;
640 	int irq, type;
641 	int ret;
642 	bool spisel_boot = false;
643 #if IS_ENABLED(CONFIG_FSL_SOC)
644 	struct mpc8xxx_spi_probe_info *pinfo = NULL;
645 #endif
646 
647 
648 	ret = of_mpc8xxx_spi_probe(ofdev);
649 	if (ret)
650 		return ret;
651 
652 	type = fsl_spi_get_type(&ofdev->dev);
653 	if (type == TYPE_FSL) {
654 		struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
655 #if IS_ENABLED(CONFIG_FSL_SOC)
656 		pinfo = to_of_pinfo(pdata);
657 
658 		spisel_boot = of_property_read_bool(np, "fsl,spisel_boot");
659 		if (spisel_boot) {
660 			pinfo->immr_spi_cs = ioremap(get_immrbase() + IMMR_SPI_CS_OFFSET, 4);
661 			if (!pinfo->immr_spi_cs)
662 				return -ENOMEM;
663 		}
664 #endif
665 		/*
666 		 * Handle the case where we have one hardwired (always selected)
667 		 * device on the first "chipselect". Else we let the core code
668 		 * handle any GPIOs or native chip selects and assign the
669 		 * appropriate callback for dealing with the CS lines. This isn't
670 		 * supported on the GRLIB variant.
671 		 */
672 		ret = gpiod_count(dev, "cs");
673 		if (ret < 0)
674 			ret = 0;
675 		if (ret == 0 && !spisel_boot)
676 			pdata->max_chipselect = 1;
677 		else
678 			pdata->max_chipselect = ret + spisel_boot;
679 	}
680 
681 	ret = of_address_to_resource(np, 0, &mem);
682 	if (ret)
683 		goto unmap_out;
684 
685 	irq = platform_get_irq(ofdev, 0);
686 	if (irq < 0) {
687 		ret = irq;
688 		goto unmap_out;
689 	}
690 
691 	host = fsl_spi_probe(dev, &mem, irq);
692 
693 	return PTR_ERR_OR_ZERO(host);
694 
695 unmap_out:
696 #if IS_ENABLED(CONFIG_FSL_SOC)
697 	if (spisel_boot)
698 		iounmap(pinfo->immr_spi_cs);
699 #endif
700 	return ret;
701 }
702 
703 static void of_fsl_spi_remove(struct platform_device *ofdev)
704 {
705 	struct spi_controller *host = platform_get_drvdata(ofdev);
706 	struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(host);
707 
708 	fsl_spi_cpm_free(mpc8xxx_spi);
709 }
710 
711 static struct platform_driver of_fsl_spi_driver = {
712 	.driver = {
713 		.name = "fsl_spi",
714 		.of_match_table = of_fsl_spi_match,
715 	},
716 	.probe		= of_fsl_spi_probe,
717 	.remove_new	= of_fsl_spi_remove,
718 };
719 
720 #ifdef CONFIG_MPC832x_RDB
721 /*
722  * XXX XXX XXX
723  * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
724  * only. The driver should go away soon, since newer MPC8323E-RDB's device
725  * tree can work with OpenFirmware driver. But for now we support old trees
726  * as well.
727  */
728 static int plat_mpc8xxx_spi_probe(struct platform_device *pdev)
729 {
730 	struct resource *mem;
731 	int irq;
732 	struct spi_controller *host;
733 
734 	if (!dev_get_platdata(&pdev->dev))
735 		return -EINVAL;
736 
737 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
738 	if (!mem)
739 		return -EINVAL;
740 
741 	irq = platform_get_irq(pdev, 0);
742 	if (irq < 0)
743 		return irq;
744 
745 	host = fsl_spi_probe(&pdev->dev, mem, irq);
746 	return PTR_ERR_OR_ZERO(host);
747 }
748 
749 static void plat_mpc8xxx_spi_remove(struct platform_device *pdev)
750 {
751 	struct spi_controller *host = platform_get_drvdata(pdev);
752 	struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(host);
753 
754 	fsl_spi_cpm_free(mpc8xxx_spi);
755 }
756 
757 MODULE_ALIAS("platform:mpc8xxx_spi");
758 static struct platform_driver mpc8xxx_spi_driver = {
759 	.probe = plat_mpc8xxx_spi_probe,
760 	.remove_new = plat_mpc8xxx_spi_remove,
761 	.driver = {
762 		.name = "mpc8xxx_spi",
763 	},
764 };
765 
766 static bool legacy_driver_failed;
767 
768 static void __init legacy_driver_register(void)
769 {
770 	legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
771 }
772 
773 static void __exit legacy_driver_unregister(void)
774 {
775 	if (legacy_driver_failed)
776 		return;
777 	platform_driver_unregister(&mpc8xxx_spi_driver);
778 }
779 #else
780 static void __init legacy_driver_register(void) {}
781 static void __exit legacy_driver_unregister(void) {}
782 #endif /* CONFIG_MPC832x_RDB */
783 
784 static int __init fsl_spi_init(void)
785 {
786 	legacy_driver_register();
787 	return platform_driver_register(&of_fsl_spi_driver);
788 }
789 module_init(fsl_spi_init);
790 
791 static void __exit fsl_spi_exit(void)
792 {
793 	platform_driver_unregister(&of_fsl_spi_driver);
794 	legacy_driver_unregister();
795 }
796 module_exit(fsl_spi_exit);
797 
798 MODULE_AUTHOR("Kumar Gala");
799 MODULE_DESCRIPTION("Simple Freescale SPI Driver");
800 MODULE_LICENSE("GPL");
801