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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 
fsl_spi_get_type(struct device * dev)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 
fsl_spi_change_mode(struct spi_device * spi)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 
fsl_spi_chipselect(struct spi_device * spi,int value)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 
fsl_spi_qe_cpu_set_shifts(u32 * rx_shift,u32 * tx_shift,int bits_per_word,int msb_first)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 
fsl_spi_grlib_set_shifts(u32 * rx_shift,u32 * tx_shift,int bits_per_word,int msb_first)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 
mspi_apply_cpu_mode_quirks(struct spi_mpc8xxx_cs * cs,struct spi_device * spi,struct mpc8xxx_spi * mpc8xxx_spi,int bits_per_word)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 
fsl_spi_setup_transfer(struct spi_device * spi,struct spi_transfer * t)206 static int fsl_spi_setup_transfer(struct spi_device *spi,
207 					struct spi_transfer *t)
208 {
209 	struct mpc8xxx_spi *mpc8xxx_spi;
210 	int bits_per_word = 0;
211 	u8 pm;
212 	u32 hz = 0;
213 	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
214 
215 	mpc8xxx_spi = spi_master_get_devdata(spi->master);
216 
217 	if (t) {
218 		bits_per_word = t->bits_per_word;
219 		hz = t->speed_hz;
220 	}
221 
222 	/* spi_transfer level calls that work per-word */
223 	if (!bits_per_word)
224 		bits_per_word = spi->bits_per_word;
225 
226 	if (!hz)
227 		hz = spi->max_speed_hz;
228 
229 	if (!(mpc8xxx_spi->flags & SPI_CPM_MODE))
230 		bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi,
231 							   mpc8xxx_spi,
232 							   bits_per_word);
233 
234 	if (bits_per_word < 0)
235 		return bits_per_word;
236 
237 	if (bits_per_word == 32)
238 		bits_per_word = 0;
239 	else
240 		bits_per_word = bits_per_word - 1;
241 
242 	/* mask out bits we are going to set */
243 	cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16
244 				  | SPMODE_PM(0xF));
245 
246 	cs->hw_mode |= SPMODE_LEN(bits_per_word);
247 
248 	if ((mpc8xxx_spi->spibrg / hz) > 64) {
249 		cs->hw_mode |= SPMODE_DIV16;
250 		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
251 		WARN_ONCE(pm > 16,
252 			  "%s: Requested speed is too low: %d Hz. Will use %d Hz instead.\n",
253 			  dev_name(&spi->dev), hz, mpc8xxx_spi->spibrg / 1024);
254 		if (pm > 16)
255 			pm = 16;
256 	} else {
257 		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
258 	}
259 	if (pm)
260 		pm--;
261 
262 	cs->hw_mode |= SPMODE_PM(pm);
263 
264 	fsl_spi_change_mode(spi);
265 	return 0;
266 }
267 
fsl_spi_cpu_bufs(struct mpc8xxx_spi * mspi,struct spi_transfer * t,unsigned int len)268 static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi,
269 				struct spi_transfer *t, unsigned int len)
270 {
271 	u32 word;
272 	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
273 
274 	mspi->count = len;
275 
276 	/* enable rx ints */
277 	mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
278 
279 	/* transmit word */
280 	word = mspi->get_tx(mspi);
281 	mpc8xxx_spi_write_reg(&reg_base->transmit, word);
282 
283 	return 0;
284 }
285 
fsl_spi_bufs(struct spi_device * spi,struct spi_transfer * t,bool is_dma_mapped)286 static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t,
287 			    bool is_dma_mapped)
288 {
289 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
290 	struct fsl_spi_reg __iomem *reg_base;
291 	unsigned int len = t->len;
292 	u8 bits_per_word;
293 	int ret;
294 
295 	reg_base = mpc8xxx_spi->reg_base;
296 	bits_per_word = spi->bits_per_word;
297 	if (t->bits_per_word)
298 		bits_per_word = t->bits_per_word;
299 
300 	if (bits_per_word > 8) {
301 		/* invalid length? */
302 		if (len & 1)
303 			return -EINVAL;
304 		len /= 2;
305 	}
306 	if (bits_per_word > 16) {
307 		/* invalid length? */
308 		if (len & 1)
309 			return -EINVAL;
310 		len /= 2;
311 	}
312 
313 	mpc8xxx_spi->tx = t->tx_buf;
314 	mpc8xxx_spi->rx = t->rx_buf;
315 
316 	reinit_completion(&mpc8xxx_spi->done);
317 
318 	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
319 		ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped);
320 	else
321 		ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len);
322 	if (ret)
323 		return ret;
324 
325 	wait_for_completion(&mpc8xxx_spi->done);
326 
327 	/* disable rx ints */
328 	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
329 
330 	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
331 		fsl_spi_cpm_bufs_complete(mpc8xxx_spi);
332 
333 	return mpc8xxx_spi->count;
334 }
335 
fsl_spi_do_one_msg(struct spi_master * master,struct spi_message * m)336 static int fsl_spi_do_one_msg(struct spi_master *master,
337 			      struct spi_message *m)
338 {
339 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
340 	struct spi_device *spi = m->spi;
341 	struct spi_transfer *t, *first;
342 	unsigned int cs_change;
343 	const int nsecs = 50;
344 	int status, last_bpw;
345 
346 	/*
347 	 * In CPU mode, optimize large byte transfers to use larger
348 	 * bits_per_word values to reduce number of interrupts taken.
349 	 */
350 	list_for_each_entry(t, &m->transfers, transfer_list) {
351 		if (!(mpc8xxx_spi->flags & SPI_CPM_MODE)) {
352 			if (t->len < 256 || t->bits_per_word != 8)
353 				continue;
354 			if ((t->len & 3) == 0)
355 				t->bits_per_word = 32;
356 			else if ((t->len & 1) == 0)
357 				t->bits_per_word = 16;
358 		} else {
359 			/*
360 			 * CPM/QE uses Little Endian for words > 8
361 			 * so transform 16 and 32 bits words into 8 bits
362 			 * Unfortnatly that doesn't work for LSB so
363 			 * reject these for now
364 			 * Note: 32 bits word, LSB works iff
365 			 * tfcr/rfcr is set to CPMFCR_GBL
366 			 */
367 			if (m->spi->mode & SPI_LSB_FIRST && t->bits_per_word > 8)
368 				return -EINVAL;
369 			if (t->bits_per_word == 16 || t->bits_per_word == 32)
370 				t->bits_per_word = 8; /* pretend its 8 bits */
371 			if (t->bits_per_word == 8 && t->len >= 256 &&
372 			    (mpc8xxx_spi->flags & SPI_CPM1))
373 				t->bits_per_word = 16;
374 		}
375 	}
376 
377 	/* Don't allow changes if CS is active */
378 	cs_change = 1;
379 	list_for_each_entry(t, &m->transfers, transfer_list) {
380 		if (cs_change)
381 			first = t;
382 		cs_change = t->cs_change;
383 		if (first->speed_hz != t->speed_hz) {
384 			dev_err(&spi->dev,
385 				"speed_hz cannot change while CS is active\n");
386 			return -EINVAL;
387 		}
388 	}
389 
390 	last_bpw = -1;
391 	cs_change = 1;
392 	status = -EINVAL;
393 	list_for_each_entry(t, &m->transfers, transfer_list) {
394 		if (cs_change || last_bpw != t->bits_per_word)
395 			status = fsl_spi_setup_transfer(spi, t);
396 		if (status < 0)
397 			break;
398 		last_bpw = t->bits_per_word;
399 
400 		if (cs_change) {
401 			fsl_spi_chipselect(spi, BITBANG_CS_ACTIVE);
402 			ndelay(nsecs);
403 		}
404 		cs_change = t->cs_change;
405 		if (t->len)
406 			status = fsl_spi_bufs(spi, t, m->is_dma_mapped);
407 		if (status) {
408 			status = -EMSGSIZE;
409 			break;
410 		}
411 		m->actual_length += t->len;
412 
413 		spi_transfer_delay_exec(t);
414 
415 		if (cs_change) {
416 			ndelay(nsecs);
417 			fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
418 			ndelay(nsecs);
419 		}
420 	}
421 
422 	m->status = status;
423 
424 	if (status || !cs_change) {
425 		ndelay(nsecs);
426 		fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
427 	}
428 
429 	fsl_spi_setup_transfer(spi, NULL);
430 	spi_finalize_current_message(master);
431 	return 0;
432 }
433 
fsl_spi_setup(struct spi_device * spi)434 static int fsl_spi_setup(struct spi_device *spi)
435 {
436 	struct mpc8xxx_spi *mpc8xxx_spi;
437 	struct fsl_spi_reg __iomem *reg_base;
438 	bool initial_setup = false;
439 	int retval;
440 	u32 hw_mode;
441 	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
442 
443 	if (!spi->max_speed_hz)
444 		return -EINVAL;
445 
446 	if (!cs) {
447 		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
448 		if (!cs)
449 			return -ENOMEM;
450 		spi_set_ctldata(spi, cs);
451 		initial_setup = true;
452 	}
453 	mpc8xxx_spi = spi_master_get_devdata(spi->master);
454 
455 	reg_base = mpc8xxx_spi->reg_base;
456 
457 	hw_mode = cs->hw_mode; /* Save original settings */
458 	cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
459 	/* mask out bits we are going to set */
460 	cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
461 			 | SPMODE_REV | SPMODE_LOOP);
462 
463 	if (spi->mode & SPI_CPHA)
464 		cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
465 	if (spi->mode & SPI_CPOL)
466 		cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
467 	if (!(spi->mode & SPI_LSB_FIRST))
468 		cs->hw_mode |= SPMODE_REV;
469 	if (spi->mode & SPI_LOOP)
470 		cs->hw_mode |= SPMODE_LOOP;
471 
472 	retval = fsl_spi_setup_transfer(spi, NULL);
473 	if (retval < 0) {
474 		cs->hw_mode = hw_mode; /* Restore settings */
475 		if (initial_setup)
476 			kfree(cs);
477 		return retval;
478 	}
479 
480 	/* Initialize chipselect - might be active for SPI_CS_HIGH mode */
481 	fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
482 
483 	return 0;
484 }
485 
fsl_spi_cleanup(struct spi_device * spi)486 static void fsl_spi_cleanup(struct spi_device *spi)
487 {
488 	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
489 
490 	kfree(cs);
491 	spi_set_ctldata(spi, NULL);
492 }
493 
fsl_spi_cpu_irq(struct mpc8xxx_spi * mspi,u32 events)494 static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
495 {
496 	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
497 
498 	/* We need handle RX first */
499 	if (events & SPIE_NE) {
500 		u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
501 
502 		if (mspi->rx)
503 			mspi->get_rx(rx_data, mspi);
504 	}
505 
506 	if ((events & SPIE_NF) == 0)
507 		/* spin until TX is done */
508 		while (((events =
509 			mpc8xxx_spi_read_reg(&reg_base->event)) &
510 						SPIE_NF) == 0)
511 			cpu_relax();
512 
513 	/* Clear the events */
514 	mpc8xxx_spi_write_reg(&reg_base->event, events);
515 
516 	mspi->count -= 1;
517 	if (mspi->count) {
518 		u32 word = mspi->get_tx(mspi);
519 
520 		mpc8xxx_spi_write_reg(&reg_base->transmit, word);
521 	} else {
522 		complete(&mspi->done);
523 	}
524 }
525 
fsl_spi_irq(s32 irq,void * context_data)526 static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
527 {
528 	struct mpc8xxx_spi *mspi = context_data;
529 	irqreturn_t ret = IRQ_NONE;
530 	u32 events;
531 	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
532 
533 	/* Get interrupt events(tx/rx) */
534 	events = mpc8xxx_spi_read_reg(&reg_base->event);
535 	if (events)
536 		ret = IRQ_HANDLED;
537 
538 	dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
539 
540 	if (mspi->flags & SPI_CPM_MODE)
541 		fsl_spi_cpm_irq(mspi, events);
542 	else
543 		fsl_spi_cpu_irq(mspi, events);
544 
545 	return ret;
546 }
547 
fsl_spi_grlib_cs_control(struct spi_device * spi,bool on)548 static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on)
549 {
550 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
551 	struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base;
552 	u32 slvsel;
553 	u16 cs = spi->chip_select;
554 
555 	if (spi->cs_gpiod) {
556 		gpiod_set_value(spi->cs_gpiod, on);
557 	} else if (cs < mpc8xxx_spi->native_chipselects) {
558 		slvsel = mpc8xxx_spi_read_reg(&reg_base->slvsel);
559 		slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs));
560 		mpc8xxx_spi_write_reg(&reg_base->slvsel, slvsel);
561 	}
562 }
563 
fsl_spi_grlib_probe(struct device * dev)564 static void fsl_spi_grlib_probe(struct device *dev)
565 {
566 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
567 	struct spi_master *master = dev_get_drvdata(dev);
568 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
569 	struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base;
570 	int mbits;
571 	u32 capabilities;
572 
573 	capabilities = mpc8xxx_spi_read_reg(&reg_base->cap);
574 
575 	mpc8xxx_spi->set_shifts = fsl_spi_grlib_set_shifts;
576 	mbits = SPCAP_MAXWLEN(capabilities);
577 	if (mbits)
578 		mpc8xxx_spi->max_bits_per_word = mbits + 1;
579 
580 	mpc8xxx_spi->native_chipselects = 0;
581 	if (SPCAP_SSEN(capabilities)) {
582 		mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities);
583 		mpc8xxx_spi_write_reg(&reg_base->slvsel, 0xffffffff);
584 	}
585 	master->num_chipselect = mpc8xxx_spi->native_chipselects;
586 	pdata->cs_control = fsl_spi_grlib_cs_control;
587 }
588 
fsl_spi_probe(struct device * dev,struct resource * mem,unsigned int irq)589 static struct spi_master *fsl_spi_probe(struct device *dev,
590 		struct resource *mem, unsigned int irq)
591 {
592 	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
593 	struct spi_master *master;
594 	struct mpc8xxx_spi *mpc8xxx_spi;
595 	struct fsl_spi_reg __iomem *reg_base;
596 	u32 regval;
597 	int ret = 0;
598 
599 	master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
600 	if (master == NULL) {
601 		ret = -ENOMEM;
602 		goto err;
603 	}
604 
605 	dev_set_drvdata(dev, master);
606 
607 	mpc8xxx_spi_probe(dev, mem, irq);
608 
609 	master->setup = fsl_spi_setup;
610 	master->cleanup = fsl_spi_cleanup;
611 	master->transfer_one_message = fsl_spi_do_one_msg;
612 	master->use_gpio_descriptors = true;
613 
614 	mpc8xxx_spi = spi_master_get_devdata(master);
615 	mpc8xxx_spi->max_bits_per_word = 32;
616 	mpc8xxx_spi->type = fsl_spi_get_type(dev);
617 
618 	ret = fsl_spi_cpm_init(mpc8xxx_spi);
619 	if (ret)
620 		goto err_cpm_init;
621 
622 	mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem);
623 	if (IS_ERR(mpc8xxx_spi->reg_base)) {
624 		ret = PTR_ERR(mpc8xxx_spi->reg_base);
625 		goto err_probe;
626 	}
627 
628 	if (mpc8xxx_spi->type == TYPE_GRLIB)
629 		fsl_spi_grlib_probe(dev);
630 
631 	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
632 		master->bits_per_word_mask =
633 			(SPI_BPW_RANGE_MASK(4, 8) | SPI_BPW_MASK(16) | SPI_BPW_MASK(32));
634 	else
635 		master->bits_per_word_mask =
636 			(SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32));
637 
638 	master->bits_per_word_mask &=
639 		SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word);
640 
641 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
642 		mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts;
643 
644 	if (mpc8xxx_spi->set_shifts)
645 		/* 8 bits per word and MSB first */
646 		mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift,
647 					&mpc8xxx_spi->tx_shift, 8, 1);
648 
649 	/* Register for SPI Interrupt */
650 	ret = devm_request_irq(dev, mpc8xxx_spi->irq, fsl_spi_irq,
651 			       0, "fsl_spi", mpc8xxx_spi);
652 
653 	if (ret != 0)
654 		goto err_probe;
655 
656 	reg_base = mpc8xxx_spi->reg_base;
657 
658 	/* SPI controller initializations */
659 	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
660 	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
661 	mpc8xxx_spi_write_reg(&reg_base->command, 0);
662 	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
663 
664 	/* Enable SPI interface */
665 	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
666 	if (mpc8xxx_spi->max_bits_per_word < 8) {
667 		regval &= ~SPMODE_LEN(0xF);
668 		regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1);
669 	}
670 	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
671 		regval |= SPMODE_OP;
672 
673 	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
674 
675 	ret = devm_spi_register_master(dev, master);
676 	if (ret < 0)
677 		goto err_probe;
678 
679 	dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
680 		 mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
681 
682 	return master;
683 
684 err_probe:
685 	fsl_spi_cpm_free(mpc8xxx_spi);
686 err_cpm_init:
687 	spi_master_put(master);
688 err:
689 	return ERR_PTR(ret);
690 }
691 
fsl_spi_cs_control(struct spi_device * spi,bool on)692 static void fsl_spi_cs_control(struct spi_device *spi, bool on)
693 {
694 	if (spi->cs_gpiod) {
695 		gpiod_set_value(spi->cs_gpiod, on);
696 	} else {
697 		struct device *dev = spi->dev.parent->parent;
698 		struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
699 		struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
700 
701 		if (WARN_ON_ONCE(!pinfo->immr_spi_cs))
702 			return;
703 		iowrite32be(on ? 0 : SPI_BOOT_SEL_BIT, pinfo->immr_spi_cs);
704 	}
705 }
706 
of_fsl_spi_probe(struct platform_device * ofdev)707 static int of_fsl_spi_probe(struct platform_device *ofdev)
708 {
709 	struct device *dev = &ofdev->dev;
710 	struct device_node *np = ofdev->dev.of_node;
711 	struct spi_master *master;
712 	struct resource mem;
713 	int irq, type;
714 	int ret;
715 	bool spisel_boot = false;
716 #if IS_ENABLED(CONFIG_FSL_SOC)
717 	struct mpc8xxx_spi_probe_info *pinfo = NULL;
718 #endif
719 
720 
721 	ret = of_mpc8xxx_spi_probe(ofdev);
722 	if (ret)
723 		return ret;
724 
725 	type = fsl_spi_get_type(&ofdev->dev);
726 	if (type == TYPE_FSL) {
727 		struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
728 #if IS_ENABLED(CONFIG_FSL_SOC)
729 		pinfo = to_of_pinfo(pdata);
730 
731 		spisel_boot = of_property_read_bool(np, "fsl,spisel_boot");
732 		if (spisel_boot) {
733 			pinfo->immr_spi_cs = ioremap(get_immrbase() + IMMR_SPI_CS_OFFSET, 4);
734 			if (!pinfo->immr_spi_cs)
735 				return -ENOMEM;
736 		}
737 #endif
738 		/*
739 		 * Handle the case where we have one hardwired (always selected)
740 		 * device on the first "chipselect". Else we let the core code
741 		 * handle any GPIOs or native chip selects and assign the
742 		 * appropriate callback for dealing with the CS lines. This isn't
743 		 * supported on the GRLIB variant.
744 		 */
745 		ret = gpiod_count(dev, "cs");
746 		if (ret < 0)
747 			ret = 0;
748 		if (ret == 0 && !spisel_boot) {
749 			pdata->max_chipselect = 1;
750 		} else {
751 			pdata->max_chipselect = ret + spisel_boot;
752 			pdata->cs_control = fsl_spi_cs_control;
753 		}
754 	}
755 
756 	ret = of_address_to_resource(np, 0, &mem);
757 	if (ret)
758 		goto unmap_out;
759 
760 	irq = platform_get_irq(ofdev, 0);
761 	if (irq < 0) {
762 		ret = irq;
763 		goto unmap_out;
764 	}
765 
766 	master = fsl_spi_probe(dev, &mem, irq);
767 
768 	return PTR_ERR_OR_ZERO(master);
769 
770 unmap_out:
771 #if IS_ENABLED(CONFIG_FSL_SOC)
772 	if (spisel_boot)
773 		iounmap(pinfo->immr_spi_cs);
774 #endif
775 	return ret;
776 }
777 
of_fsl_spi_remove(struct platform_device * ofdev)778 static int of_fsl_spi_remove(struct platform_device *ofdev)
779 {
780 	struct spi_master *master = platform_get_drvdata(ofdev);
781 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
782 
783 	fsl_spi_cpm_free(mpc8xxx_spi);
784 	return 0;
785 }
786 
787 static struct platform_driver of_fsl_spi_driver = {
788 	.driver = {
789 		.name = "fsl_spi",
790 		.of_match_table = of_fsl_spi_match,
791 	},
792 	.probe		= of_fsl_spi_probe,
793 	.remove		= of_fsl_spi_remove,
794 };
795 
796 #ifdef CONFIG_MPC832x_RDB
797 /*
798  * XXX XXX XXX
799  * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
800  * only. The driver should go away soon, since newer MPC8323E-RDB's device
801  * tree can work with OpenFirmware driver. But for now we support old trees
802  * as well.
803  */
plat_mpc8xxx_spi_probe(struct platform_device * pdev)804 static int plat_mpc8xxx_spi_probe(struct platform_device *pdev)
805 {
806 	struct resource *mem;
807 	int irq;
808 	struct spi_master *master;
809 
810 	if (!dev_get_platdata(&pdev->dev))
811 		return -EINVAL;
812 
813 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
814 	if (!mem)
815 		return -EINVAL;
816 
817 	irq = platform_get_irq(pdev, 0);
818 	if (irq <= 0)
819 		return -EINVAL;
820 
821 	master = fsl_spi_probe(&pdev->dev, mem, irq);
822 	return PTR_ERR_OR_ZERO(master);
823 }
824 
plat_mpc8xxx_spi_remove(struct platform_device * pdev)825 static int plat_mpc8xxx_spi_remove(struct platform_device *pdev)
826 {
827 	struct spi_master *master = platform_get_drvdata(pdev);
828 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
829 
830 	fsl_spi_cpm_free(mpc8xxx_spi);
831 
832 	return 0;
833 }
834 
835 MODULE_ALIAS("platform:mpc8xxx_spi");
836 static struct platform_driver mpc8xxx_spi_driver = {
837 	.probe = plat_mpc8xxx_spi_probe,
838 	.remove = plat_mpc8xxx_spi_remove,
839 	.driver = {
840 		.name = "mpc8xxx_spi",
841 	},
842 };
843 
844 static bool legacy_driver_failed;
845 
legacy_driver_register(void)846 static void __init legacy_driver_register(void)
847 {
848 	legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
849 }
850 
legacy_driver_unregister(void)851 static void __exit legacy_driver_unregister(void)
852 {
853 	if (legacy_driver_failed)
854 		return;
855 	platform_driver_unregister(&mpc8xxx_spi_driver);
856 }
857 #else
legacy_driver_register(void)858 static void __init legacy_driver_register(void) {}
legacy_driver_unregister(void)859 static void __exit legacy_driver_unregister(void) {}
860 #endif /* CONFIG_MPC832x_RDB */
861 
fsl_spi_init(void)862 static int __init fsl_spi_init(void)
863 {
864 	legacy_driver_register();
865 	return platform_driver_register(&of_fsl_spi_driver);
866 }
867 module_init(fsl_spi_init);
868 
fsl_spi_exit(void)869 static void __exit fsl_spi_exit(void)
870 {
871 	platform_driver_unregister(&of_fsl_spi_driver);
872 	legacy_driver_unregister();
873 }
874 module_exit(fsl_spi_exit);
875 
876 MODULE_AUTHOR("Kumar Gala");
877 MODULE_DESCRIPTION("Simple Freescale SPI Driver");
878 MODULE_LICENSE("GPL");
879