xref: /openbmc/linux/drivers/spi/spi-fsl-spi.c (revision b830f94f)
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.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_gpio.h>
32 #include <linux/of_platform.h>
33 #include <linux/platform_device.h>
34 #include <linux/spi/spi.h>
35 #include <linux/spi/spi_bitbang.h>
36 #include <linux/types.h>
37 
38 #ifdef CONFIG_FSL_SOC
39 #include <sysdev/fsl_soc.h>
40 #endif
41 
42 /* Specific to the MPC8306/MPC8309 */
43 #define IMMR_SPI_CS_OFFSET 0x14c
44 #define SPI_BOOT_SEL_BIT   0x80000000
45 
46 #include "spi-fsl-lib.h"
47 #include "spi-fsl-cpm.h"
48 #include "spi-fsl-spi.h"
49 
50 #define TYPE_FSL	0
51 #define TYPE_GRLIB	1
52 
53 struct fsl_spi_match_data {
54 	int type;
55 };
56 
57 static struct fsl_spi_match_data of_fsl_spi_fsl_config = {
58 	.type = TYPE_FSL,
59 };
60 
61 static struct fsl_spi_match_data of_fsl_spi_grlib_config = {
62 	.type = TYPE_GRLIB,
63 };
64 
65 static const struct of_device_id of_fsl_spi_match[] = {
66 	{
67 		.compatible = "fsl,spi",
68 		.data = &of_fsl_spi_fsl_config,
69 	},
70 	{
71 		.compatible = "aeroflexgaisler,spictrl",
72 		.data = &of_fsl_spi_grlib_config,
73 	},
74 	{}
75 };
76 MODULE_DEVICE_TABLE(of, of_fsl_spi_match);
77 
78 static int fsl_spi_get_type(struct device *dev)
79 {
80 	const struct of_device_id *match;
81 
82 	if (dev->of_node) {
83 		match = of_match_node(of_fsl_spi_match, dev->of_node);
84 		if (match && match->data)
85 			return ((struct fsl_spi_match_data *)match->data)->type;
86 	}
87 	return TYPE_FSL;
88 }
89 
90 static void fsl_spi_change_mode(struct spi_device *spi)
91 {
92 	struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
93 	struct spi_mpc8xxx_cs *cs = spi->controller_state;
94 	struct fsl_spi_reg *reg_base = mspi->reg_base;
95 	__be32 __iomem *mode = &reg_base->mode;
96 	unsigned long flags;
97 
98 	if (cs->hw_mode == mpc8xxx_spi_read_reg(mode))
99 		return;
100 
101 	/* Turn off IRQs locally to minimize time that SPI is disabled. */
102 	local_irq_save(flags);
103 
104 	/* Turn off SPI unit prior changing mode */
105 	mpc8xxx_spi_write_reg(mode, cs->hw_mode & ~SPMODE_ENABLE);
106 
107 	/* When in CPM mode, we need to reinit tx and rx. */
108 	if (mspi->flags & SPI_CPM_MODE) {
109 		fsl_spi_cpm_reinit_txrx(mspi);
110 	}
111 	mpc8xxx_spi_write_reg(mode, cs->hw_mode);
112 	local_irq_restore(flags);
113 }
114 
115 static void fsl_spi_chipselect(struct spi_device *spi, int value)
116 {
117 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
118 	struct fsl_spi_platform_data *pdata;
119 	bool pol = spi->mode & SPI_CS_HIGH;
120 	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
121 
122 	pdata = spi->dev.parent->parent->platform_data;
123 
124 	if (value == BITBANG_CS_INACTIVE) {
125 		if (pdata->cs_control)
126 			pdata->cs_control(spi, !pol);
127 	}
128 
129 	if (value == BITBANG_CS_ACTIVE) {
130 		mpc8xxx_spi->rx_shift = cs->rx_shift;
131 		mpc8xxx_spi->tx_shift = cs->tx_shift;
132 		mpc8xxx_spi->get_rx = cs->get_rx;
133 		mpc8xxx_spi->get_tx = cs->get_tx;
134 
135 		fsl_spi_change_mode(spi);
136 
137 		if (pdata->cs_control)
138 			pdata->cs_control(spi, pol);
139 	}
140 }
141 
142 static void fsl_spi_qe_cpu_set_shifts(u32 *rx_shift, u32 *tx_shift,
143 				      int bits_per_word, int msb_first)
144 {
145 	*rx_shift = 0;
146 	*tx_shift = 0;
147 	if (msb_first) {
148 		if (bits_per_word <= 8) {
149 			*rx_shift = 16;
150 			*tx_shift = 24;
151 		} else if (bits_per_word <= 16) {
152 			*rx_shift = 16;
153 			*tx_shift = 16;
154 		}
155 	} else {
156 		if (bits_per_word <= 8)
157 			*rx_shift = 8;
158 	}
159 }
160 
161 static void fsl_spi_grlib_set_shifts(u32 *rx_shift, u32 *tx_shift,
162 				     int bits_per_word, int msb_first)
163 {
164 	*rx_shift = 0;
165 	*tx_shift = 0;
166 	if (bits_per_word <= 16) {
167 		if (msb_first) {
168 			*rx_shift = 16; /* LSB in bit 16 */
169 			*tx_shift = 32 - bits_per_word; /* MSB in bit 31 */
170 		} else {
171 			*rx_shift = 16 - bits_per_word; /* MSB in bit 15 */
172 		}
173 	}
174 }
175 
176 static int mspi_apply_cpu_mode_quirks(struct spi_mpc8xxx_cs *cs,
177 				struct spi_device *spi,
178 				struct mpc8xxx_spi *mpc8xxx_spi,
179 				int bits_per_word)
180 {
181 	cs->rx_shift = 0;
182 	cs->tx_shift = 0;
183 	if (bits_per_word <= 8) {
184 		cs->get_rx = mpc8xxx_spi_rx_buf_u8;
185 		cs->get_tx = mpc8xxx_spi_tx_buf_u8;
186 	} else if (bits_per_word <= 16) {
187 		cs->get_rx = mpc8xxx_spi_rx_buf_u16;
188 		cs->get_tx = mpc8xxx_spi_tx_buf_u16;
189 	} else if (bits_per_word <= 32) {
190 		cs->get_rx = mpc8xxx_spi_rx_buf_u32;
191 		cs->get_tx = mpc8xxx_spi_tx_buf_u32;
192 	} else
193 		return -EINVAL;
194 
195 	if (mpc8xxx_spi->set_shifts)
196 		mpc8xxx_spi->set_shifts(&cs->rx_shift, &cs->tx_shift,
197 					bits_per_word,
198 					!(spi->mode & SPI_LSB_FIRST));
199 
200 	mpc8xxx_spi->rx_shift = cs->rx_shift;
201 	mpc8xxx_spi->tx_shift = cs->tx_shift;
202 	mpc8xxx_spi->get_rx = cs->get_rx;
203 	mpc8xxx_spi->get_tx = cs->get_tx;
204 
205 	return bits_per_word;
206 }
207 
208 static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs,
209 				struct spi_device *spi,
210 				int bits_per_word)
211 {
212 	/* QE uses Little Endian for words > 8
213 	 * so transform all words > 8 into 8 bits
214 	 * Unfortnatly that doesn't work for LSB so
215 	 * reject these for now */
216 	/* Note: 32 bits word, LSB works iff
217 	 * tfcr/rfcr is set to CPMFCR_GBL */
218 	if (spi->mode & SPI_LSB_FIRST &&
219 	    bits_per_word > 8)
220 		return -EINVAL;
221 	if (bits_per_word > 8)
222 		return 8; /* pretend its 8 bits */
223 	return bits_per_word;
224 }
225 
226 static int fsl_spi_setup_transfer(struct spi_device *spi,
227 					struct spi_transfer *t)
228 {
229 	struct mpc8xxx_spi *mpc8xxx_spi;
230 	int bits_per_word = 0;
231 	u8 pm;
232 	u32 hz = 0;
233 	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
234 
235 	mpc8xxx_spi = spi_master_get_devdata(spi->master);
236 
237 	if (t) {
238 		bits_per_word = t->bits_per_word;
239 		hz = t->speed_hz;
240 	}
241 
242 	/* spi_transfer level calls that work per-word */
243 	if (!bits_per_word)
244 		bits_per_word = spi->bits_per_word;
245 
246 	if (!hz)
247 		hz = spi->max_speed_hz;
248 
249 	if (!(mpc8xxx_spi->flags & SPI_CPM_MODE))
250 		bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi,
251 							   mpc8xxx_spi,
252 							   bits_per_word);
253 	else if (mpc8xxx_spi->flags & SPI_QE)
254 		bits_per_word = mspi_apply_qe_mode_quirks(cs, spi,
255 							  bits_per_word);
256 
257 	if (bits_per_word < 0)
258 		return bits_per_word;
259 
260 	if (bits_per_word == 32)
261 		bits_per_word = 0;
262 	else
263 		bits_per_word = bits_per_word - 1;
264 
265 	/* mask out bits we are going to set */
266 	cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16
267 				  | SPMODE_PM(0xF));
268 
269 	cs->hw_mode |= SPMODE_LEN(bits_per_word);
270 
271 	if ((mpc8xxx_spi->spibrg / hz) > 64) {
272 		cs->hw_mode |= SPMODE_DIV16;
273 		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
274 		WARN_ONCE(pm > 16,
275 			  "%s: Requested speed is too low: %d Hz. Will use %d Hz instead.\n",
276 			  dev_name(&spi->dev), hz, mpc8xxx_spi->spibrg / 1024);
277 		if (pm > 16)
278 			pm = 16;
279 	} else {
280 		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
281 	}
282 	if (pm)
283 		pm--;
284 
285 	cs->hw_mode |= SPMODE_PM(pm);
286 
287 	fsl_spi_change_mode(spi);
288 	return 0;
289 }
290 
291 static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi,
292 				struct spi_transfer *t, unsigned int len)
293 {
294 	u32 word;
295 	struct fsl_spi_reg *reg_base = mspi->reg_base;
296 
297 	mspi->count = len;
298 
299 	/* enable rx ints */
300 	mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
301 
302 	/* transmit word */
303 	word = mspi->get_tx(mspi);
304 	mpc8xxx_spi_write_reg(&reg_base->transmit, word);
305 
306 	return 0;
307 }
308 
309 static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t,
310 			    bool is_dma_mapped)
311 {
312 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
313 	struct fsl_spi_reg *reg_base;
314 	unsigned int len = t->len;
315 	u8 bits_per_word;
316 	int ret;
317 
318 	reg_base = mpc8xxx_spi->reg_base;
319 	bits_per_word = spi->bits_per_word;
320 	if (t->bits_per_word)
321 		bits_per_word = t->bits_per_word;
322 
323 	if (bits_per_word > 8) {
324 		/* invalid length? */
325 		if (len & 1)
326 			return -EINVAL;
327 		len /= 2;
328 	}
329 	if (bits_per_word > 16) {
330 		/* invalid length? */
331 		if (len & 1)
332 			return -EINVAL;
333 		len /= 2;
334 	}
335 
336 	mpc8xxx_spi->tx = t->tx_buf;
337 	mpc8xxx_spi->rx = t->rx_buf;
338 
339 	reinit_completion(&mpc8xxx_spi->done);
340 
341 	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
342 		ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped);
343 	else
344 		ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len);
345 	if (ret)
346 		return ret;
347 
348 	wait_for_completion(&mpc8xxx_spi->done);
349 
350 	/* disable rx ints */
351 	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
352 
353 	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
354 		fsl_spi_cpm_bufs_complete(mpc8xxx_spi);
355 
356 	return mpc8xxx_spi->count;
357 }
358 
359 static int fsl_spi_do_one_msg(struct spi_master *master,
360 			      struct spi_message *m)
361 {
362 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
363 	struct spi_device *spi = m->spi;
364 	struct spi_transfer *t, *first;
365 	unsigned int cs_change;
366 	const int nsecs = 50;
367 	int status, last_bpw;
368 
369 	/*
370 	 * In CPU mode, optimize large byte transfers to use larger
371 	 * bits_per_word values to reduce number of interrupts taken.
372 	 */
373 	if (!(mpc8xxx_spi->flags & SPI_CPM_MODE)) {
374 		list_for_each_entry(t, &m->transfers, transfer_list) {
375 			if (t->len < 256 || t->bits_per_word != 8)
376 				continue;
377 			if ((t->len & 3) == 0)
378 				t->bits_per_word = 32;
379 			else if ((t->len & 1) == 0)
380 				t->bits_per_word = 16;
381 		}
382 	}
383 
384 	/* Don't allow changes if CS is active */
385 	cs_change = 1;
386 	list_for_each_entry(t, &m->transfers, transfer_list) {
387 		if (cs_change)
388 			first = t;
389 		cs_change = t->cs_change;
390 		if (first->speed_hz != t->speed_hz) {
391 			dev_err(&spi->dev,
392 				"speed_hz cannot change while CS is active\n");
393 			return -EINVAL;
394 		}
395 	}
396 
397 	last_bpw = -1;
398 	cs_change = 1;
399 	status = -EINVAL;
400 	list_for_each_entry(t, &m->transfers, transfer_list) {
401 		if (cs_change || last_bpw != t->bits_per_word)
402 			status = fsl_spi_setup_transfer(spi, t);
403 		if (status < 0)
404 			break;
405 		last_bpw = t->bits_per_word;
406 
407 		if (cs_change) {
408 			fsl_spi_chipselect(spi, BITBANG_CS_ACTIVE);
409 			ndelay(nsecs);
410 		}
411 		cs_change = t->cs_change;
412 		if (t->len)
413 			status = fsl_spi_bufs(spi, t, m->is_dma_mapped);
414 		if (status) {
415 			status = -EMSGSIZE;
416 			break;
417 		}
418 		m->actual_length += t->len;
419 
420 		if (t->delay_usecs)
421 			udelay(t->delay_usecs);
422 
423 		if (cs_change) {
424 			ndelay(nsecs);
425 			fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
426 			ndelay(nsecs);
427 		}
428 	}
429 
430 	m->status = status;
431 
432 	if (status || !cs_change) {
433 		ndelay(nsecs);
434 		fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
435 	}
436 
437 	fsl_spi_setup_transfer(spi, NULL);
438 	spi_finalize_current_message(master);
439 	return 0;
440 }
441 
442 static int fsl_spi_setup(struct spi_device *spi)
443 {
444 	struct mpc8xxx_spi *mpc8xxx_spi;
445 	struct fsl_spi_reg *reg_base;
446 	int retval;
447 	u32 hw_mode;
448 	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
449 
450 	if (!spi->max_speed_hz)
451 		return -EINVAL;
452 
453 	if (!cs) {
454 		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
455 		if (!cs)
456 			return -ENOMEM;
457 		spi_set_ctldata(spi, cs);
458 	}
459 	mpc8xxx_spi = spi_master_get_devdata(spi->master);
460 
461 	reg_base = mpc8xxx_spi->reg_base;
462 
463 	hw_mode = cs->hw_mode; /* Save original settings */
464 	cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
465 	/* mask out bits we are going to set */
466 	cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
467 			 | SPMODE_REV | SPMODE_LOOP);
468 
469 	if (spi->mode & SPI_CPHA)
470 		cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
471 	if (spi->mode & SPI_CPOL)
472 		cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
473 	if (!(spi->mode & SPI_LSB_FIRST))
474 		cs->hw_mode |= SPMODE_REV;
475 	if (spi->mode & SPI_LOOP)
476 		cs->hw_mode |= SPMODE_LOOP;
477 
478 	retval = fsl_spi_setup_transfer(spi, NULL);
479 	if (retval < 0) {
480 		cs->hw_mode = hw_mode; /* Restore settings */
481 		return retval;
482 	}
483 
484 	if (mpc8xxx_spi->type == TYPE_GRLIB) {
485 		if (gpio_is_valid(spi->cs_gpio)) {
486 			int desel;
487 
488 			retval = gpio_request(spi->cs_gpio,
489 					      dev_name(&spi->dev));
490 			if (retval)
491 				return retval;
492 
493 			desel = !(spi->mode & SPI_CS_HIGH);
494 			retval = gpio_direction_output(spi->cs_gpio, desel);
495 			if (retval) {
496 				gpio_free(spi->cs_gpio);
497 				return retval;
498 			}
499 		} else if (spi->cs_gpio != -ENOENT) {
500 			if (spi->cs_gpio < 0)
501 				return spi->cs_gpio;
502 			return -EINVAL;
503 		}
504 		/* When spi->cs_gpio == -ENOENT, a hole in the phandle list
505 		 * indicates to use native chipselect if present, or allow for
506 		 * an always selected chip
507 		 */
508 	}
509 
510 	/* Initialize chipselect - might be active for SPI_CS_HIGH mode */
511 	fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
512 
513 	return 0;
514 }
515 
516 static void fsl_spi_cleanup(struct spi_device *spi)
517 {
518 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
519 	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
520 
521 	if (mpc8xxx_spi->type == TYPE_GRLIB && gpio_is_valid(spi->cs_gpio))
522 		gpio_free(spi->cs_gpio);
523 
524 	kfree(cs);
525 	spi_set_ctldata(spi, NULL);
526 }
527 
528 static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
529 {
530 	struct fsl_spi_reg *reg_base = mspi->reg_base;
531 
532 	/* We need handle RX first */
533 	if (events & SPIE_NE) {
534 		u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
535 
536 		if (mspi->rx)
537 			mspi->get_rx(rx_data, mspi);
538 	}
539 
540 	if ((events & SPIE_NF) == 0)
541 		/* spin until TX is done */
542 		while (((events =
543 			mpc8xxx_spi_read_reg(&reg_base->event)) &
544 						SPIE_NF) == 0)
545 			cpu_relax();
546 
547 	/* Clear the events */
548 	mpc8xxx_spi_write_reg(&reg_base->event, events);
549 
550 	mspi->count -= 1;
551 	if (mspi->count) {
552 		u32 word = mspi->get_tx(mspi);
553 
554 		mpc8xxx_spi_write_reg(&reg_base->transmit, word);
555 	} else {
556 		complete(&mspi->done);
557 	}
558 }
559 
560 static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
561 {
562 	struct mpc8xxx_spi *mspi = context_data;
563 	irqreturn_t ret = IRQ_NONE;
564 	u32 events;
565 	struct fsl_spi_reg *reg_base = mspi->reg_base;
566 
567 	/* Get interrupt events(tx/rx) */
568 	events = mpc8xxx_spi_read_reg(&reg_base->event);
569 	if (events)
570 		ret = IRQ_HANDLED;
571 
572 	dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
573 
574 	if (mspi->flags & SPI_CPM_MODE)
575 		fsl_spi_cpm_irq(mspi, events);
576 	else
577 		fsl_spi_cpu_irq(mspi, events);
578 
579 	return ret;
580 }
581 
582 static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on)
583 {
584 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
585 	struct fsl_spi_reg *reg_base = mpc8xxx_spi->reg_base;
586 	u32 slvsel;
587 	u16 cs = spi->chip_select;
588 
589 	if (gpio_is_valid(spi->cs_gpio)) {
590 		gpio_set_value(spi->cs_gpio, on);
591 	} else if (cs < mpc8xxx_spi->native_chipselects) {
592 		slvsel = mpc8xxx_spi_read_reg(&reg_base->slvsel);
593 		slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs));
594 		mpc8xxx_spi_write_reg(&reg_base->slvsel, slvsel);
595 	}
596 }
597 
598 static void fsl_spi_grlib_probe(struct device *dev)
599 {
600 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
601 	struct spi_master *master = dev_get_drvdata(dev);
602 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
603 	struct fsl_spi_reg *reg_base = mpc8xxx_spi->reg_base;
604 	int mbits;
605 	u32 capabilities;
606 
607 	capabilities = mpc8xxx_spi_read_reg(&reg_base->cap);
608 
609 	mpc8xxx_spi->set_shifts = fsl_spi_grlib_set_shifts;
610 	mbits = SPCAP_MAXWLEN(capabilities);
611 	if (mbits)
612 		mpc8xxx_spi->max_bits_per_word = mbits + 1;
613 
614 	mpc8xxx_spi->native_chipselects = 0;
615 	if (SPCAP_SSEN(capabilities)) {
616 		mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities);
617 		mpc8xxx_spi_write_reg(&reg_base->slvsel, 0xffffffff);
618 	}
619 	master->num_chipselect = mpc8xxx_spi->native_chipselects;
620 	pdata->cs_control = fsl_spi_grlib_cs_control;
621 }
622 
623 static struct spi_master * fsl_spi_probe(struct device *dev,
624 		struct resource *mem, unsigned int irq)
625 {
626 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
627 	struct spi_master *master;
628 	struct mpc8xxx_spi *mpc8xxx_spi;
629 	struct fsl_spi_reg *reg_base;
630 	u32 regval;
631 	int ret = 0;
632 
633 	master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
634 	if (master == NULL) {
635 		ret = -ENOMEM;
636 		goto err;
637 	}
638 
639 	dev_set_drvdata(dev, master);
640 
641 	mpc8xxx_spi_probe(dev, mem, irq);
642 
643 	master->setup = fsl_spi_setup;
644 	master->cleanup = fsl_spi_cleanup;
645 	master->transfer_one_message = fsl_spi_do_one_msg;
646 
647 	mpc8xxx_spi = spi_master_get_devdata(master);
648 	mpc8xxx_spi->max_bits_per_word = 32;
649 	mpc8xxx_spi->type = fsl_spi_get_type(dev);
650 
651 	ret = fsl_spi_cpm_init(mpc8xxx_spi);
652 	if (ret)
653 		goto err_cpm_init;
654 
655 	mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem);
656 	if (IS_ERR(mpc8xxx_spi->reg_base)) {
657 		ret = PTR_ERR(mpc8xxx_spi->reg_base);
658 		goto err_probe;
659 	}
660 
661 	if (mpc8xxx_spi->type == TYPE_GRLIB)
662 		fsl_spi_grlib_probe(dev);
663 
664 	master->bits_per_word_mask =
665 		(SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32)) &
666 		SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word);
667 
668 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
669 		mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts;
670 
671 	if (mpc8xxx_spi->set_shifts)
672 		/* 8 bits per word and MSB first */
673 		mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift,
674 					&mpc8xxx_spi->tx_shift, 8, 1);
675 
676 	/* Register for SPI Interrupt */
677 	ret = devm_request_irq(dev, mpc8xxx_spi->irq, fsl_spi_irq,
678 			       0, "fsl_spi", mpc8xxx_spi);
679 
680 	if (ret != 0)
681 		goto err_probe;
682 
683 	reg_base = mpc8xxx_spi->reg_base;
684 
685 	/* SPI controller initializations */
686 	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
687 	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
688 	mpc8xxx_spi_write_reg(&reg_base->command, 0);
689 	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
690 
691 	/* Enable SPI interface */
692 	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
693 	if (mpc8xxx_spi->max_bits_per_word < 8) {
694 		regval &= ~SPMODE_LEN(0xF);
695 		regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1);
696 	}
697 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
698 		regval |= SPMODE_OP;
699 
700 	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
701 
702 	ret = devm_spi_register_master(dev, master);
703 	if (ret < 0)
704 		goto err_probe;
705 
706 	dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
707 		 mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
708 
709 	return master;
710 
711 err_probe:
712 	fsl_spi_cpm_free(mpc8xxx_spi);
713 err_cpm_init:
714 	spi_master_put(master);
715 err:
716 	return ERR_PTR(ret);
717 }
718 
719 static void fsl_spi_cs_control(struct spi_device *spi, bool on)
720 {
721 	struct device *dev = spi->dev.parent->parent;
722 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
723 	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
724 	u16 cs = spi->chip_select;
725 
726 	if (cs < pinfo->ngpios) {
727 		int gpio = pinfo->gpios[cs];
728 		bool alow = pinfo->alow_flags[cs];
729 
730 		gpio_set_value(gpio, on ^ alow);
731 	} else {
732 		if (WARN_ON_ONCE(cs > pinfo->ngpios || !pinfo->immr_spi_cs))
733 			return;
734 		iowrite32be(on ? SPI_BOOT_SEL_BIT : 0, pinfo->immr_spi_cs);
735 	}
736 }
737 
738 static int of_fsl_spi_get_chipselects(struct device *dev)
739 {
740 	struct device_node *np = dev->of_node;
741 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
742 	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
743 	bool spisel_boot = IS_ENABLED(CONFIG_FSL_SOC) &&
744 		of_property_read_bool(np, "fsl,spisel_boot");
745 	int ngpios;
746 	int i = 0;
747 	int ret;
748 
749 	ngpios = of_gpio_count(np);
750 	ngpios = max(ngpios, 0);
751 	if (ngpios == 0 && !spisel_boot) {
752 		/*
753 		 * SPI w/o chip-select line. One SPI device is still permitted
754 		 * though.
755 		 */
756 		pdata->max_chipselect = 1;
757 		return 0;
758 	}
759 
760 	pinfo->ngpios = ngpios;
761 	pinfo->gpios = kmalloc_array(ngpios, sizeof(*pinfo->gpios),
762 				     GFP_KERNEL);
763 	if (!pinfo->gpios)
764 		return -ENOMEM;
765 	memset(pinfo->gpios, -1, ngpios * sizeof(*pinfo->gpios));
766 
767 	pinfo->alow_flags = kcalloc(ngpios, sizeof(*pinfo->alow_flags),
768 				    GFP_KERNEL);
769 	if (!pinfo->alow_flags) {
770 		ret = -ENOMEM;
771 		goto err_alloc_flags;
772 	}
773 
774 	for (; i < ngpios; i++) {
775 		int gpio;
776 		enum of_gpio_flags flags;
777 
778 		gpio = of_get_gpio_flags(np, i, &flags);
779 		if (!gpio_is_valid(gpio)) {
780 			dev_err(dev, "invalid gpio #%d: %d\n", i, gpio);
781 			ret = gpio;
782 			goto err_loop;
783 		}
784 
785 		ret = gpio_request(gpio, dev_name(dev));
786 		if (ret) {
787 			dev_err(dev, "can't request gpio #%d: %d\n", i, ret);
788 			goto err_loop;
789 		}
790 
791 		pinfo->gpios[i] = gpio;
792 		pinfo->alow_flags[i] = flags & OF_GPIO_ACTIVE_LOW;
793 
794 		ret = gpio_direction_output(pinfo->gpios[i],
795 					    pinfo->alow_flags[i]);
796 		if (ret) {
797 			dev_err(dev,
798 				"can't set output direction for gpio #%d: %d\n",
799 				i, ret);
800 			goto err_loop;
801 		}
802 	}
803 
804 #if IS_ENABLED(CONFIG_FSL_SOC)
805 	if (spisel_boot) {
806 		pinfo->immr_spi_cs = ioremap(get_immrbase() + IMMR_SPI_CS_OFFSET, 4);
807 		if (!pinfo->immr_spi_cs) {
808 			ret = -ENOMEM;
809 			i = ngpios - 1;
810 			goto err_loop;
811 		}
812 	}
813 #endif
814 
815 	pdata->max_chipselect = ngpios + spisel_boot;
816 	pdata->cs_control = fsl_spi_cs_control;
817 
818 	return 0;
819 
820 err_loop:
821 	while (i >= 0) {
822 		if (gpio_is_valid(pinfo->gpios[i]))
823 			gpio_free(pinfo->gpios[i]);
824 		i--;
825 	}
826 
827 	kfree(pinfo->alow_flags);
828 	pinfo->alow_flags = NULL;
829 err_alloc_flags:
830 	kfree(pinfo->gpios);
831 	pinfo->gpios = NULL;
832 	return ret;
833 }
834 
835 static int of_fsl_spi_free_chipselects(struct device *dev)
836 {
837 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
838 	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
839 	int i;
840 
841 	if (!pinfo->gpios)
842 		return 0;
843 
844 	for (i = 0; i < pdata->max_chipselect; i++) {
845 		if (gpio_is_valid(pinfo->gpios[i]))
846 			gpio_free(pinfo->gpios[i]);
847 	}
848 
849 	kfree(pinfo->gpios);
850 	kfree(pinfo->alow_flags);
851 	return 0;
852 }
853 
854 static int of_fsl_spi_probe(struct platform_device *ofdev)
855 {
856 	struct device *dev = &ofdev->dev;
857 	struct device_node *np = ofdev->dev.of_node;
858 	struct spi_master *master;
859 	struct resource mem;
860 	int irq = 0, type;
861 	int ret = -ENOMEM;
862 
863 	ret = of_mpc8xxx_spi_probe(ofdev);
864 	if (ret)
865 		return ret;
866 
867 	type = fsl_spi_get_type(&ofdev->dev);
868 	if (type == TYPE_FSL) {
869 		ret = of_fsl_spi_get_chipselects(dev);
870 		if (ret)
871 			goto err;
872 	}
873 
874 	ret = of_address_to_resource(np, 0, &mem);
875 	if (ret)
876 		goto err;
877 
878 	irq = irq_of_parse_and_map(np, 0);
879 	if (!irq) {
880 		ret = -EINVAL;
881 		goto err;
882 	}
883 
884 	master = fsl_spi_probe(dev, &mem, irq);
885 	if (IS_ERR(master)) {
886 		ret = PTR_ERR(master);
887 		goto err;
888 	}
889 
890 	return 0;
891 
892 err:
893 	irq_dispose_mapping(irq);
894 	if (type == TYPE_FSL)
895 		of_fsl_spi_free_chipselects(dev);
896 	return ret;
897 }
898 
899 static int of_fsl_spi_remove(struct platform_device *ofdev)
900 {
901 	struct spi_master *master = platform_get_drvdata(ofdev);
902 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
903 
904 	fsl_spi_cpm_free(mpc8xxx_spi);
905 	if (mpc8xxx_spi->type == TYPE_FSL)
906 		of_fsl_spi_free_chipselects(&ofdev->dev);
907 	return 0;
908 }
909 
910 static struct platform_driver of_fsl_spi_driver = {
911 	.driver = {
912 		.name = "fsl_spi",
913 		.of_match_table = of_fsl_spi_match,
914 	},
915 	.probe		= of_fsl_spi_probe,
916 	.remove		= of_fsl_spi_remove,
917 };
918 
919 #ifdef CONFIG_MPC832x_RDB
920 /*
921  * XXX XXX XXX
922  * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
923  * only. The driver should go away soon, since newer MPC8323E-RDB's device
924  * tree can work with OpenFirmware driver. But for now we support old trees
925  * as well.
926  */
927 static int plat_mpc8xxx_spi_probe(struct platform_device *pdev)
928 {
929 	struct resource *mem;
930 	int irq;
931 	struct spi_master *master;
932 
933 	if (!dev_get_platdata(&pdev->dev))
934 		return -EINVAL;
935 
936 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
937 	if (!mem)
938 		return -EINVAL;
939 
940 	irq = platform_get_irq(pdev, 0);
941 	if (irq <= 0)
942 		return -EINVAL;
943 
944 	master = fsl_spi_probe(&pdev->dev, mem, irq);
945 	return PTR_ERR_OR_ZERO(master);
946 }
947 
948 static int plat_mpc8xxx_spi_remove(struct platform_device *pdev)
949 {
950 	struct spi_master *master = platform_get_drvdata(pdev);
951 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
952 
953 	fsl_spi_cpm_free(mpc8xxx_spi);
954 
955 	return 0;
956 }
957 
958 MODULE_ALIAS("platform:mpc8xxx_spi");
959 static struct platform_driver mpc8xxx_spi_driver = {
960 	.probe = plat_mpc8xxx_spi_probe,
961 	.remove = plat_mpc8xxx_spi_remove,
962 	.driver = {
963 		.name = "mpc8xxx_spi",
964 	},
965 };
966 
967 static bool legacy_driver_failed;
968 
969 static void __init legacy_driver_register(void)
970 {
971 	legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
972 }
973 
974 static void __exit legacy_driver_unregister(void)
975 {
976 	if (legacy_driver_failed)
977 		return;
978 	platform_driver_unregister(&mpc8xxx_spi_driver);
979 }
980 #else
981 static void __init legacy_driver_register(void) {}
982 static void __exit legacy_driver_unregister(void) {}
983 #endif /* CONFIG_MPC832x_RDB */
984 
985 static int __init fsl_spi_init(void)
986 {
987 	legacy_driver_register();
988 	return platform_driver_register(&of_fsl_spi_driver);
989 }
990 module_init(fsl_spi_init);
991 
992 static void __exit fsl_spi_exit(void)
993 {
994 	platform_driver_unregister(&of_fsl_spi_driver);
995 	legacy_driver_unregister();
996 }
997 module_exit(fsl_spi_exit);
998 
999 MODULE_AUTHOR("Kumar Gala");
1000 MODULE_DESCRIPTION("Simple Freescale SPI Driver");
1001 MODULE_LICENSE("GPL");
1002