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v6.8
  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
 52struct fsl_spi_match_data {
 53	int type;
 54};
 55
 56static struct fsl_spi_match_data of_fsl_spi_fsl_config = {
 57	.type = TYPE_FSL,
 58};
 59
 60static struct fsl_spi_match_data of_fsl_spi_grlib_config = {
 61	.type = TYPE_GRLIB,
 62};
 63
 64static 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};
 75MODULE_DEVICE_TABLE(of, of_fsl_spi_match);
 76
 77static 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
 89static 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
114static 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
133static 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
148static 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
177static 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
234static 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
252static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t,
253			    bool is_dma_mapped)
254{
255	struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(spi->controller);
256	struct fsl_spi_reg __iomem *reg_base;
257	unsigned int len = t->len;
258	u8 bits_per_word;
259	int ret;
260
261	reg_base = mpc8xxx_spi->reg_base;
262	bits_per_word = spi->bits_per_word;
263	if (t->bits_per_word)
264		bits_per_word = t->bits_per_word;
265
266	if (bits_per_word > 8)
 
 
 
267		len /= 2;
268	if (bits_per_word > 16)
 
 
 
 
269		len /= 2;
 
270
271	mpc8xxx_spi->tx = t->tx_buf;
272	mpc8xxx_spi->rx = t->rx_buf;
273
274	reinit_completion(&mpc8xxx_spi->done);
275
276	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
277		ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped);
278	else
279		ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len);
280	if (ret)
281		return ret;
282
283	wait_for_completion(&mpc8xxx_spi->done);
284
285	/* disable rx ints */
286	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
287
288	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
289		fsl_spi_cpm_bufs_complete(mpc8xxx_spi);
290
291	return mpc8xxx_spi->count;
292}
293
294static int fsl_spi_prepare_message(struct spi_controller *ctlr,
295				   struct spi_message *m)
296{
297	struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(ctlr);
298	struct spi_transfer *t;
299	struct spi_transfer *first;
300
301	first = list_first_entry(&m->transfers, struct spi_transfer,
302				 transfer_list);
303
304	/*
305	 * In CPU mode, optimize large byte transfers to use larger
306	 * bits_per_word values to reduce number of interrupts taken.
307	 *
308	 * Some glitches can appear on the SPI clock when the mode changes.
309	 * Check that there is no speed change during the transfer and set it up
310	 * now to change the mode without having a chip-select asserted.
311	 */
312	list_for_each_entry(t, &m->transfers, transfer_list) {
313		if (t->speed_hz != first->speed_hz) {
314			dev_err(&m->spi->dev,
315				"speed_hz cannot change during message.\n");
316			return -EINVAL;
317		}
318		if (!(mpc8xxx_spi->flags & SPI_CPM_MODE)) {
319			if (t->len < 256 || t->bits_per_word != 8)
320				continue;
321			if ((t->len & 3) == 0)
322				t->bits_per_word = 32;
323			else if ((t->len & 1) == 0)
324				t->bits_per_word = 16;
325		} else {
326			/*
327			 * CPM/QE uses Little Endian for words > 8
328			 * so transform 16 and 32 bits words into 8 bits
329			 * Unfortnatly that doesn't work for LSB so
330			 * reject these for now
331			 * Note: 32 bits word, LSB works iff
332			 * tfcr/rfcr is set to CPMFCR_GBL
333			 */
334			if (m->spi->mode & SPI_LSB_FIRST && t->bits_per_word > 8)
335				return -EINVAL;
336			if (t->bits_per_word == 16 || t->bits_per_word == 32)
337				t->bits_per_word = 8; /* pretend its 8 bits */
338			if (t->bits_per_word == 8 && t->len >= 256 &&
339			    (mpc8xxx_spi->flags & SPI_CPM1))
340				t->bits_per_word = 16;
341		}
342	}
343	return fsl_spi_setup_transfer(m->spi, first);
344}
345
346static int fsl_spi_transfer_one(struct spi_controller *controller,
347				struct spi_device *spi,
348				struct spi_transfer *t)
349{
350	int status;
351
352	status = fsl_spi_setup_transfer(spi, t);
353	if (status < 0)
354		return status;
355	if (t->len)
356		status = fsl_spi_bufs(spi, t, !!t->tx_dma || !!t->rx_dma);
357	if (status > 0)
358		return -EMSGSIZE;
359
360	return status;
361}
362
363static int fsl_spi_unprepare_message(struct spi_controller *controller,
364				     struct spi_message *msg)
365{
366	return fsl_spi_setup_transfer(msg->spi, NULL);
367}
368
369static int fsl_spi_setup(struct spi_device *spi)
370{
371	struct mpc8xxx_spi *mpc8xxx_spi;
372	struct fsl_spi_reg __iomem *reg_base;
373	bool initial_setup = false;
374	int retval;
375	u32 hw_mode;
376	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
377
378	if (!spi->max_speed_hz)
379		return -EINVAL;
380
381	if (!cs) {
382		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
383		if (!cs)
384			return -ENOMEM;
385		spi_set_ctldata(spi, cs);
386		initial_setup = true;
387	}
388	mpc8xxx_spi = spi_controller_get_devdata(spi->controller);
389
390	reg_base = mpc8xxx_spi->reg_base;
391
392	hw_mode = cs->hw_mode; /* Save original settings */
393	cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
394	/* mask out bits we are going to set */
395	cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
396			 | SPMODE_REV | SPMODE_LOOP);
397
398	if (spi->mode & SPI_CPHA)
399		cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
400	if (spi->mode & SPI_CPOL)
401		cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
402	if (!(spi->mode & SPI_LSB_FIRST))
403		cs->hw_mode |= SPMODE_REV;
404	if (spi->mode & SPI_LOOP)
405		cs->hw_mode |= SPMODE_LOOP;
406
407	retval = fsl_spi_setup_transfer(spi, NULL);
408	if (retval < 0) {
409		cs->hw_mode = hw_mode; /* Restore settings */
410		if (initial_setup)
411			kfree(cs);
412		return retval;
413	}
414
415	return 0;
416}
417
418static void fsl_spi_cleanup(struct spi_device *spi)
419{
420	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
421
422	kfree(cs);
423	spi_set_ctldata(spi, NULL);
424}
425
426static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
427{
428	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
429
430	/* We need handle RX first */
431	if (events & SPIE_NE) {
432		u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
433
434		if (mspi->rx)
435			mspi->get_rx(rx_data, mspi);
436	}
437
438	if ((events & SPIE_NF) == 0)
439		/* spin until TX is done */
440		while (((events =
441			mpc8xxx_spi_read_reg(&reg_base->event)) &
442						SPIE_NF) == 0)
443			cpu_relax();
444
445	/* Clear the events */
446	mpc8xxx_spi_write_reg(&reg_base->event, events);
447
448	mspi->count -= 1;
449	if (mspi->count) {
450		u32 word = mspi->get_tx(mspi);
451
452		mpc8xxx_spi_write_reg(&reg_base->transmit, word);
453	} else {
454		complete(&mspi->done);
455	}
456}
457
458static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
459{
460	struct mpc8xxx_spi *mspi = context_data;
461	irqreturn_t ret = IRQ_NONE;
462	u32 events;
463	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
464
465	/* Get interrupt events(tx/rx) */
466	events = mpc8xxx_spi_read_reg(&reg_base->event);
467	if (events)
468		ret = IRQ_HANDLED;
469
470	dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
471
472	if (mspi->flags & SPI_CPM_MODE)
473		fsl_spi_cpm_irq(mspi, events);
474	else
475		fsl_spi_cpu_irq(mspi, events);
476
477	return ret;
478}
479
480static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on)
481{
482	struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(spi->controller);
483	struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base;
484	u32 slvsel;
485	u16 cs = spi_get_chipselect(spi, 0);
486
487	if (cs < mpc8xxx_spi->native_chipselects) {
488		slvsel = mpc8xxx_spi_read_reg(&reg_base->slvsel);
489		slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs));
490		mpc8xxx_spi_write_reg(&reg_base->slvsel, slvsel);
491	}
492}
493
494static void fsl_spi_grlib_probe(struct device *dev)
495{
496	struct spi_controller *host = dev_get_drvdata(dev);
497	struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(host);
498	struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base;
499	int mbits;
500	u32 capabilities;
501
502	capabilities = mpc8xxx_spi_read_reg(&reg_base->cap);
503
504	mpc8xxx_spi->set_shifts = fsl_spi_grlib_set_shifts;
505	mbits = SPCAP_MAXWLEN(capabilities);
506	if (mbits)
507		mpc8xxx_spi->max_bits_per_word = mbits + 1;
508
509	mpc8xxx_spi->native_chipselects = 0;
510	if (SPCAP_SSEN(capabilities)) {
511		mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities);
512		mpc8xxx_spi_write_reg(&reg_base->slvsel, 0xffffffff);
513	}
514	host->num_chipselect = mpc8xxx_spi->native_chipselects;
515	host->set_cs = fsl_spi_grlib_cs_control;
516}
517
518static void fsl_spi_cs_control(struct spi_device *spi, bool on)
519{
520	struct device *dev = spi->dev.parent->parent;
521	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
522	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
523
524	if (WARN_ON_ONCE(!pinfo->immr_spi_cs))
525		return;
526	iowrite32be(on ? 0 : SPI_BOOT_SEL_BIT, pinfo->immr_spi_cs);
527}
528
529static struct spi_controller *fsl_spi_probe(struct device *dev,
530		struct resource *mem, unsigned int irq)
531{
532	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
533	struct spi_controller *host;
534	struct mpc8xxx_spi *mpc8xxx_spi;
535	struct fsl_spi_reg __iomem *reg_base;
536	u32 regval;
537	int ret = 0;
538
539	host = spi_alloc_host(dev, sizeof(struct mpc8xxx_spi));
540	if (host == NULL) {
541		ret = -ENOMEM;
542		goto err;
543	}
544
545	dev_set_drvdata(dev, host);
546
547	mpc8xxx_spi_probe(dev, mem, irq);
548
549	host->setup = fsl_spi_setup;
550	host->cleanup = fsl_spi_cleanup;
551	host->prepare_message = fsl_spi_prepare_message;
552	host->transfer_one = fsl_spi_transfer_one;
553	host->unprepare_message = fsl_spi_unprepare_message;
554	host->use_gpio_descriptors = true;
555	host->set_cs = fsl_spi_cs_control;
556
557	mpc8xxx_spi = spi_controller_get_devdata(host);
558	mpc8xxx_spi->max_bits_per_word = 32;
559	mpc8xxx_spi->type = fsl_spi_get_type(dev);
560
561	ret = fsl_spi_cpm_init(mpc8xxx_spi);
562	if (ret)
563		goto err_cpm_init;
564
565	mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem);
566	if (IS_ERR(mpc8xxx_spi->reg_base)) {
567		ret = PTR_ERR(mpc8xxx_spi->reg_base);
568		goto err_probe;
569	}
570
571	if (mpc8xxx_spi->type == TYPE_GRLIB)
572		fsl_spi_grlib_probe(dev);
573
574	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
575		host->bits_per_word_mask =
576			(SPI_BPW_RANGE_MASK(4, 8) | SPI_BPW_MASK(16) | SPI_BPW_MASK(32));
577	else
578		host->bits_per_word_mask =
579			(SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32));
580
581	host->bits_per_word_mask &=
582		SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word);
583
584	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
585		mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts;
586
587	if (mpc8xxx_spi->set_shifts)
588		/* 8 bits per word and MSB first */
589		mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift,
590					&mpc8xxx_spi->tx_shift, 8, 1);
591
592	/* Register for SPI Interrupt */
593	ret = devm_request_irq(dev, mpc8xxx_spi->irq, fsl_spi_irq,
594			       0, "fsl_spi", mpc8xxx_spi);
595
596	if (ret != 0)
597		goto err_probe;
598
599	reg_base = mpc8xxx_spi->reg_base;
600
601	/* SPI controller initializations */
602	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
603	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
604	mpc8xxx_spi_write_reg(&reg_base->command, 0);
605	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
606
607	/* Enable SPI interface */
608	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
609	if (mpc8xxx_spi->max_bits_per_word < 8) {
610		regval &= ~SPMODE_LEN(0xF);
611		regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1);
612	}
613	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
614		regval |= SPMODE_OP;
615
616	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
617
618	ret = devm_spi_register_controller(dev, host);
619	if (ret < 0)
620		goto err_probe;
621
622	dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
623		 mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
624
625	return host;
626
627err_probe:
628	fsl_spi_cpm_free(mpc8xxx_spi);
629err_cpm_init:
630	spi_controller_put(host);
631err:
632	return ERR_PTR(ret);
633}
634
635static int of_fsl_spi_probe(struct platform_device *ofdev)
636{
637	struct device *dev = &ofdev->dev;
638	struct device_node *np = ofdev->dev.of_node;
639	struct spi_controller *host;
640	struct resource mem;
641	int irq, type;
642	int ret;
643	bool spisel_boot = false;
644#if IS_ENABLED(CONFIG_FSL_SOC)
645	struct mpc8xxx_spi_probe_info *pinfo = NULL;
646#endif
647
648
649	ret = of_mpc8xxx_spi_probe(ofdev);
650	if (ret)
651		return ret;
652
653	type = fsl_spi_get_type(&ofdev->dev);
654	if (type == TYPE_FSL) {
655		struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
656#if IS_ENABLED(CONFIG_FSL_SOC)
657		pinfo = to_of_pinfo(pdata);
658
659		spisel_boot = of_property_read_bool(np, "fsl,spisel_boot");
660		if (spisel_boot) {
661			pinfo->immr_spi_cs = ioremap(get_immrbase() + IMMR_SPI_CS_OFFSET, 4);
662			if (!pinfo->immr_spi_cs)
663				return -ENOMEM;
664		}
665#endif
666		/*
667		 * Handle the case where we have one hardwired (always selected)
668		 * device on the first "chipselect". Else we let the core code
669		 * handle any GPIOs or native chip selects and assign the
670		 * appropriate callback for dealing with the CS lines. This isn't
671		 * supported on the GRLIB variant.
672		 */
673		ret = gpiod_count(dev, "cs");
674		if (ret < 0)
675			ret = 0;
676		if (ret == 0 && !spisel_boot)
677			pdata->max_chipselect = 1;
678		else
679			pdata->max_chipselect = ret + spisel_boot;
680	}
681
682	ret = of_address_to_resource(np, 0, &mem);
683	if (ret)
684		goto unmap_out;
685
686	irq = platform_get_irq(ofdev, 0);
687	if (irq < 0) {
688		ret = irq;
689		goto unmap_out;
690	}
691
692	host = fsl_spi_probe(dev, &mem, irq);
693
694	return PTR_ERR_OR_ZERO(host);
695
696unmap_out:
697#if IS_ENABLED(CONFIG_FSL_SOC)
698	if (spisel_boot)
699		iounmap(pinfo->immr_spi_cs);
700#endif
701	return ret;
702}
703
704static void of_fsl_spi_remove(struct platform_device *ofdev)
705{
706	struct spi_controller *host = platform_get_drvdata(ofdev);
707	struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(host);
708
709	fsl_spi_cpm_free(mpc8xxx_spi);
 
710}
711
712static struct platform_driver of_fsl_spi_driver = {
713	.driver = {
714		.name = "fsl_spi",
715		.of_match_table = of_fsl_spi_match,
716	},
717	.probe		= of_fsl_spi_probe,
718	.remove_new	= of_fsl_spi_remove,
719};
720
721#ifdef CONFIG_MPC832x_RDB
722/*
723 * XXX XXX XXX
724 * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
725 * only. The driver should go away soon, since newer MPC8323E-RDB's device
726 * tree can work with OpenFirmware driver. But for now we support old trees
727 * as well.
728 */
729static int plat_mpc8xxx_spi_probe(struct platform_device *pdev)
730{
731	struct resource *mem;
732	int irq;
733	struct spi_controller *host;
734
735	if (!dev_get_platdata(&pdev->dev))
736		return -EINVAL;
737
738	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
739	if (!mem)
740		return -EINVAL;
741
742	irq = platform_get_irq(pdev, 0);
743	if (irq < 0)
744		return irq;
745
746	host = fsl_spi_probe(&pdev->dev, mem, irq);
747	return PTR_ERR_OR_ZERO(host);
748}
749
750static void plat_mpc8xxx_spi_remove(struct platform_device *pdev)
751{
752	struct spi_controller *host = platform_get_drvdata(pdev);
753	struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(host);
754
755	fsl_spi_cpm_free(mpc8xxx_spi);
 
 
756}
757
758MODULE_ALIAS("platform:mpc8xxx_spi");
759static struct platform_driver mpc8xxx_spi_driver = {
760	.probe = plat_mpc8xxx_spi_probe,
761	.remove_new = plat_mpc8xxx_spi_remove,
762	.driver = {
763		.name = "mpc8xxx_spi",
764	},
765};
766
767static bool legacy_driver_failed;
768
769static void __init legacy_driver_register(void)
770{
771	legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
772}
773
774static void __exit legacy_driver_unregister(void)
775{
776	if (legacy_driver_failed)
777		return;
778	platform_driver_unregister(&mpc8xxx_spi_driver);
779}
780#else
781static void __init legacy_driver_register(void) {}
782static void __exit legacy_driver_unregister(void) {}
783#endif /* CONFIG_MPC832x_RDB */
784
785static int __init fsl_spi_init(void)
786{
787	legacy_driver_register();
788	return platform_driver_register(&of_fsl_spi_driver);
789}
790module_init(fsl_spi_init);
791
792static void __exit fsl_spi_exit(void)
793{
794	platform_driver_unregister(&of_fsl_spi_driver);
795	legacy_driver_unregister();
796}
797module_exit(fsl_spi_exit);
798
799MODULE_AUTHOR("Kumar Gala");
800MODULE_DESCRIPTION("Simple Freescale SPI Driver");
801MODULE_LICENSE("GPL");
v6.2
  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
 52struct fsl_spi_match_data {
 53	int type;
 54};
 55
 56static struct fsl_spi_match_data of_fsl_spi_fsl_config = {
 57	.type = TYPE_FSL,
 58};
 59
 60static struct fsl_spi_match_data of_fsl_spi_grlib_config = {
 61	.type = TYPE_GRLIB,
 62};
 63
 64static 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};
 75MODULE_DEVICE_TABLE(of, of_fsl_spi_match);
 76
 77static 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
 89static 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
114static 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
133static 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
148static int 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	} else
165		return -EINVAL;
166
167	if (mpc8xxx_spi->set_shifts)
168		mpc8xxx_spi->set_shifts(&cs->rx_shift, &cs->tx_shift,
169					bits_per_word,
170					!(spi->mode & SPI_LSB_FIRST));
171
172	mpc8xxx_spi->rx_shift = cs->rx_shift;
173	mpc8xxx_spi->tx_shift = cs->tx_shift;
174	mpc8xxx_spi->get_rx = cs->get_rx;
175	mpc8xxx_spi->get_tx = cs->get_tx;
176
177	return bits_per_word;
178}
179
180static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs,
181				struct spi_device *spi,
182				int bits_per_word)
183{
184	/* QE uses Little Endian for words > 8
185	 * so transform all words > 8 into 8 bits
186	 * Unfortnatly that doesn't work for LSB so
187	 * reject these for now */
188	/* Note: 32 bits word, LSB works iff
189	 * tfcr/rfcr is set to CPMFCR_GBL */
190	if (spi->mode & SPI_LSB_FIRST &&
191	    bits_per_word > 8)
192		return -EINVAL;
193	if (bits_per_word > 8)
194		return 8; /* pretend its 8 bits */
195	return bits_per_word;
196}
197
198static int fsl_spi_setup_transfer(struct spi_device *spi,
199					struct spi_transfer *t)
200{
201	struct mpc8xxx_spi *mpc8xxx_spi;
202	int bits_per_word = 0;
203	u8 pm;
204	u32 hz = 0;
205	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
206
207	mpc8xxx_spi = spi_master_get_devdata(spi->master);
208
209	if (t) {
210		bits_per_word = t->bits_per_word;
211		hz = t->speed_hz;
212	}
213
214	/* spi_transfer level calls that work per-word */
215	if (!bits_per_word)
216		bits_per_word = spi->bits_per_word;
217
218	if (!hz)
219		hz = spi->max_speed_hz;
220
221	if (!(mpc8xxx_spi->flags & SPI_CPM_MODE))
222		bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi,
223							   mpc8xxx_spi,
224							   bits_per_word);
225	else if (mpc8xxx_spi->flags & SPI_QE)
226		bits_per_word = mspi_apply_qe_mode_quirks(cs, spi,
227							  bits_per_word);
228
229	if (bits_per_word < 0)
230		return bits_per_word;
231
232	if (bits_per_word == 32)
233		bits_per_word = 0;
234	else
235		bits_per_word = bits_per_word - 1;
236
237	/* mask out bits we are going to set */
238	cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16
239				  | SPMODE_PM(0xF));
240
241	cs->hw_mode |= SPMODE_LEN(bits_per_word);
242
243	if ((mpc8xxx_spi->spibrg / hz) > 64) {
244		cs->hw_mode |= SPMODE_DIV16;
245		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
246		WARN_ONCE(pm > 16,
247			  "%s: Requested speed is too low: %d Hz. Will use %d Hz instead.\n",
248			  dev_name(&spi->dev), hz, mpc8xxx_spi->spibrg / 1024);
249		if (pm > 16)
250			pm = 16;
251	} else {
252		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
253	}
254	if (pm)
255		pm--;
256
257	cs->hw_mode |= SPMODE_PM(pm);
258
259	fsl_spi_change_mode(spi);
260	return 0;
261}
262
263static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi,
264				struct spi_transfer *t, unsigned int len)
265{
266	u32 word;
267	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
268
269	mspi->count = len;
270
271	/* enable rx ints */
272	mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
273
274	/* transmit word */
275	word = mspi->get_tx(mspi);
276	mpc8xxx_spi_write_reg(&reg_base->transmit, word);
277
278	return 0;
279}
280
281static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t,
282			    bool is_dma_mapped)
283{
284	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
285	struct fsl_spi_reg __iomem *reg_base;
286	unsigned int len = t->len;
287	u8 bits_per_word;
288	int ret;
289
290	reg_base = mpc8xxx_spi->reg_base;
291	bits_per_word = spi->bits_per_word;
292	if (t->bits_per_word)
293		bits_per_word = t->bits_per_word;
294
295	if (bits_per_word > 8) {
296		/* invalid length? */
297		if (len & 1)
298			return -EINVAL;
299		len /= 2;
300	}
301	if (bits_per_word > 16) {
302		/* invalid length? */
303		if (len & 1)
304			return -EINVAL;
305		len /= 2;
306	}
307
308	mpc8xxx_spi->tx = t->tx_buf;
309	mpc8xxx_spi->rx = t->rx_buf;
310
311	reinit_completion(&mpc8xxx_spi->done);
312
313	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
314		ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped);
315	else
316		ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len);
317	if (ret)
318		return ret;
319
320	wait_for_completion(&mpc8xxx_spi->done);
321
322	/* disable rx ints */
323	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
324
325	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
326		fsl_spi_cpm_bufs_complete(mpc8xxx_spi);
327
328	return mpc8xxx_spi->count;
329}
330
331static int fsl_spi_prepare_message(struct spi_controller *ctlr,
332				   struct spi_message *m)
333{
334	struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(ctlr);
335	struct spi_transfer *t;
336	struct spi_transfer *first;
337
338	first = list_first_entry(&m->transfers, struct spi_transfer,
339				 transfer_list);
340
341	/*
342	 * In CPU mode, optimize large byte transfers to use larger
343	 * bits_per_word values to reduce number of interrupts taken.
344	 *
345	 * Some glitches can appear on the SPI clock when the mode changes.
346	 * Check that there is no speed change during the transfer and set it up
347	 * now to change the mode without having a chip-select asserted.
348	 */
349	list_for_each_entry(t, &m->transfers, transfer_list) {
350		if (t->speed_hz != first->speed_hz) {
351			dev_err(&m->spi->dev,
352				"speed_hz cannot change during message.\n");
353			return -EINVAL;
354		}
355		if (!(mpc8xxx_spi->flags & SPI_CPM_MODE)) {
356			if (t->len < 256 || t->bits_per_word != 8)
357				continue;
358			if ((t->len & 3) == 0)
359				t->bits_per_word = 32;
360			else if ((t->len & 1) == 0)
361				t->bits_per_word = 16;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
362		}
363	}
364	return fsl_spi_setup_transfer(m->spi, first);
365}
366
367static int fsl_spi_transfer_one(struct spi_controller *controller,
368				struct spi_device *spi,
369				struct spi_transfer *t)
370{
371	int status;
372
373	status = fsl_spi_setup_transfer(spi, t);
374	if (status < 0)
375		return status;
376	if (t->len)
377		status = fsl_spi_bufs(spi, t, !!t->tx_dma || !!t->rx_dma);
378	if (status > 0)
379		return -EMSGSIZE;
380
381	return status;
382}
383
384static int fsl_spi_unprepare_message(struct spi_controller *controller,
385				     struct spi_message *msg)
386{
387	return fsl_spi_setup_transfer(msg->spi, NULL);
388}
389
390static int fsl_spi_setup(struct spi_device *spi)
391{
392	struct mpc8xxx_spi *mpc8xxx_spi;
393	struct fsl_spi_reg __iomem *reg_base;
394	bool initial_setup = false;
395	int retval;
396	u32 hw_mode;
397	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
398
399	if (!spi->max_speed_hz)
400		return -EINVAL;
401
402	if (!cs) {
403		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
404		if (!cs)
405			return -ENOMEM;
406		spi_set_ctldata(spi, cs);
407		initial_setup = true;
408	}
409	mpc8xxx_spi = spi_master_get_devdata(spi->master);
410
411	reg_base = mpc8xxx_spi->reg_base;
412
413	hw_mode = cs->hw_mode; /* Save original settings */
414	cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
415	/* mask out bits we are going to set */
416	cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
417			 | SPMODE_REV | SPMODE_LOOP);
418
419	if (spi->mode & SPI_CPHA)
420		cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
421	if (spi->mode & SPI_CPOL)
422		cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
423	if (!(spi->mode & SPI_LSB_FIRST))
424		cs->hw_mode |= SPMODE_REV;
425	if (spi->mode & SPI_LOOP)
426		cs->hw_mode |= SPMODE_LOOP;
427
428	retval = fsl_spi_setup_transfer(spi, NULL);
429	if (retval < 0) {
430		cs->hw_mode = hw_mode; /* Restore settings */
431		if (initial_setup)
432			kfree(cs);
433		return retval;
434	}
435
436	return 0;
437}
438
439static void fsl_spi_cleanup(struct spi_device *spi)
440{
441	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
442
443	kfree(cs);
444	spi_set_ctldata(spi, NULL);
445}
446
447static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
448{
449	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
450
451	/* We need handle RX first */
452	if (events & SPIE_NE) {
453		u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
454
455		if (mspi->rx)
456			mspi->get_rx(rx_data, mspi);
457	}
458
459	if ((events & SPIE_NF) == 0)
460		/* spin until TX is done */
461		while (((events =
462			mpc8xxx_spi_read_reg(&reg_base->event)) &
463						SPIE_NF) == 0)
464			cpu_relax();
465
466	/* Clear the events */
467	mpc8xxx_spi_write_reg(&reg_base->event, events);
468
469	mspi->count -= 1;
470	if (mspi->count) {
471		u32 word = mspi->get_tx(mspi);
472
473		mpc8xxx_spi_write_reg(&reg_base->transmit, word);
474	} else {
475		complete(&mspi->done);
476	}
477}
478
479static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
480{
481	struct mpc8xxx_spi *mspi = context_data;
482	irqreturn_t ret = IRQ_NONE;
483	u32 events;
484	struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
485
486	/* Get interrupt events(tx/rx) */
487	events = mpc8xxx_spi_read_reg(&reg_base->event);
488	if (events)
489		ret = IRQ_HANDLED;
490
491	dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
492
493	if (mspi->flags & SPI_CPM_MODE)
494		fsl_spi_cpm_irq(mspi, events);
495	else
496		fsl_spi_cpu_irq(mspi, events);
497
498	return ret;
499}
500
501static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on)
502{
503	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
504	struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base;
505	u32 slvsel;
506	u16 cs = spi->chip_select;
507
508	if (cs < mpc8xxx_spi->native_chipselects) {
509		slvsel = mpc8xxx_spi_read_reg(&reg_base->slvsel);
510		slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs));
511		mpc8xxx_spi_write_reg(&reg_base->slvsel, slvsel);
512	}
513}
514
515static void fsl_spi_grlib_probe(struct device *dev)
516{
517	struct spi_master *master = dev_get_drvdata(dev);
518	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
519	struct fsl_spi_reg __iomem *reg_base = mpc8xxx_spi->reg_base;
520	int mbits;
521	u32 capabilities;
522
523	capabilities = mpc8xxx_spi_read_reg(&reg_base->cap);
524
525	mpc8xxx_spi->set_shifts = fsl_spi_grlib_set_shifts;
526	mbits = SPCAP_MAXWLEN(capabilities);
527	if (mbits)
528		mpc8xxx_spi->max_bits_per_word = mbits + 1;
529
530	mpc8xxx_spi->native_chipselects = 0;
531	if (SPCAP_SSEN(capabilities)) {
532		mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities);
533		mpc8xxx_spi_write_reg(&reg_base->slvsel, 0xffffffff);
534	}
535	master->num_chipselect = mpc8xxx_spi->native_chipselects;
536	master->set_cs = fsl_spi_grlib_cs_control;
537}
538
539static void fsl_spi_cs_control(struct spi_device *spi, bool on)
540{
541	struct device *dev = spi->dev.parent->parent;
542	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
543	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
544
545	if (WARN_ON_ONCE(!pinfo->immr_spi_cs))
546		return;
547	iowrite32be(on ? 0 : SPI_BOOT_SEL_BIT, pinfo->immr_spi_cs);
548}
549
550static struct spi_master *fsl_spi_probe(struct device *dev,
551		struct resource *mem, unsigned int irq)
552{
553	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
554	struct spi_master *master;
555	struct mpc8xxx_spi *mpc8xxx_spi;
556	struct fsl_spi_reg __iomem *reg_base;
557	u32 regval;
558	int ret = 0;
559
560	master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
561	if (master == NULL) {
562		ret = -ENOMEM;
563		goto err;
564	}
565
566	dev_set_drvdata(dev, master);
567
568	mpc8xxx_spi_probe(dev, mem, irq);
569
570	master->setup = fsl_spi_setup;
571	master->cleanup = fsl_spi_cleanup;
572	master->prepare_message = fsl_spi_prepare_message;
573	master->transfer_one = fsl_spi_transfer_one;
574	master->unprepare_message = fsl_spi_unprepare_message;
575	master->use_gpio_descriptors = true;
576	master->set_cs = fsl_spi_cs_control;
577
578	mpc8xxx_spi = spi_master_get_devdata(master);
579	mpc8xxx_spi->max_bits_per_word = 32;
580	mpc8xxx_spi->type = fsl_spi_get_type(dev);
581
582	ret = fsl_spi_cpm_init(mpc8xxx_spi);
583	if (ret)
584		goto err_cpm_init;
585
586	mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem);
587	if (IS_ERR(mpc8xxx_spi->reg_base)) {
588		ret = PTR_ERR(mpc8xxx_spi->reg_base);
589		goto err_probe;
590	}
591
592	if (mpc8xxx_spi->type == TYPE_GRLIB)
593		fsl_spi_grlib_probe(dev);
594
595	master->bits_per_word_mask =
596		(SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32)) &
 
 
 
 
 
 
597		SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word);
598
599	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
600		mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts;
601
602	if (mpc8xxx_spi->set_shifts)
603		/* 8 bits per word and MSB first */
604		mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift,
605					&mpc8xxx_spi->tx_shift, 8, 1);
606
607	/* Register for SPI Interrupt */
608	ret = devm_request_irq(dev, mpc8xxx_spi->irq, fsl_spi_irq,
609			       0, "fsl_spi", mpc8xxx_spi);
610
611	if (ret != 0)
612		goto err_probe;
613
614	reg_base = mpc8xxx_spi->reg_base;
615
616	/* SPI controller initializations */
617	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
618	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
619	mpc8xxx_spi_write_reg(&reg_base->command, 0);
620	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
621
622	/* Enable SPI interface */
623	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
624	if (mpc8xxx_spi->max_bits_per_word < 8) {
625		regval &= ~SPMODE_LEN(0xF);
626		regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1);
627	}
628	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
629		regval |= SPMODE_OP;
630
631	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
632
633	ret = devm_spi_register_master(dev, master);
634	if (ret < 0)
635		goto err_probe;
636
637	dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
638		 mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
639
640	return master;
641
642err_probe:
643	fsl_spi_cpm_free(mpc8xxx_spi);
644err_cpm_init:
645	spi_master_put(master);
646err:
647	return ERR_PTR(ret);
648}
649
650static int of_fsl_spi_probe(struct platform_device *ofdev)
651{
652	struct device *dev = &ofdev->dev;
653	struct device_node *np = ofdev->dev.of_node;
654	struct spi_master *master;
655	struct resource mem;
656	int irq, type;
657	int ret;
658	bool spisel_boot = false;
659#if IS_ENABLED(CONFIG_FSL_SOC)
660	struct mpc8xxx_spi_probe_info *pinfo = NULL;
661#endif
662
663
664	ret = of_mpc8xxx_spi_probe(ofdev);
665	if (ret)
666		return ret;
667
668	type = fsl_spi_get_type(&ofdev->dev);
669	if (type == TYPE_FSL) {
670		struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
671#if IS_ENABLED(CONFIG_FSL_SOC)
672		pinfo = to_of_pinfo(pdata);
673
674		spisel_boot = of_property_read_bool(np, "fsl,spisel_boot");
675		if (spisel_boot) {
676			pinfo->immr_spi_cs = ioremap(get_immrbase() + IMMR_SPI_CS_OFFSET, 4);
677			if (!pinfo->immr_spi_cs)
678				return -ENOMEM;
679		}
680#endif
681		/*
682		 * Handle the case where we have one hardwired (always selected)
683		 * device on the first "chipselect". Else we let the core code
684		 * handle any GPIOs or native chip selects and assign the
685		 * appropriate callback for dealing with the CS lines. This isn't
686		 * supported on the GRLIB variant.
687		 */
688		ret = gpiod_count(dev, "cs");
689		if (ret < 0)
690			ret = 0;
691		if (ret == 0 && !spisel_boot)
692			pdata->max_chipselect = 1;
693		else
694			pdata->max_chipselect = ret + spisel_boot;
695	}
696
697	ret = of_address_to_resource(np, 0, &mem);
698	if (ret)
699		goto unmap_out;
700
701	irq = platform_get_irq(ofdev, 0);
702	if (irq < 0) {
703		ret = irq;
704		goto unmap_out;
705	}
706
707	master = fsl_spi_probe(dev, &mem, irq);
708
709	return PTR_ERR_OR_ZERO(master);
710
711unmap_out:
712#if IS_ENABLED(CONFIG_FSL_SOC)
713	if (spisel_boot)
714		iounmap(pinfo->immr_spi_cs);
715#endif
716	return ret;
717}
718
719static int of_fsl_spi_remove(struct platform_device *ofdev)
720{
721	struct spi_master *master = platform_get_drvdata(ofdev);
722	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
723
724	fsl_spi_cpm_free(mpc8xxx_spi);
725	return 0;
726}
727
728static struct platform_driver of_fsl_spi_driver = {
729	.driver = {
730		.name = "fsl_spi",
731		.of_match_table = of_fsl_spi_match,
732	},
733	.probe		= of_fsl_spi_probe,
734	.remove		= of_fsl_spi_remove,
735};
736
737#ifdef CONFIG_MPC832x_RDB
738/*
739 * XXX XXX XXX
740 * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
741 * only. The driver should go away soon, since newer MPC8323E-RDB's device
742 * tree can work with OpenFirmware driver. But for now we support old trees
743 * as well.
744 */
745static int plat_mpc8xxx_spi_probe(struct platform_device *pdev)
746{
747	struct resource *mem;
748	int irq;
749	struct spi_master *master;
750
751	if (!dev_get_platdata(&pdev->dev))
752		return -EINVAL;
753
754	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
755	if (!mem)
756		return -EINVAL;
757
758	irq = platform_get_irq(pdev, 0);
759	if (irq <= 0)
760		return -EINVAL;
761
762	master = fsl_spi_probe(&pdev->dev, mem, irq);
763	return PTR_ERR_OR_ZERO(master);
764}
765
766static int plat_mpc8xxx_spi_remove(struct platform_device *pdev)
767{
768	struct spi_master *master = platform_get_drvdata(pdev);
769	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
770
771	fsl_spi_cpm_free(mpc8xxx_spi);
772
773	return 0;
774}
775
776MODULE_ALIAS("platform:mpc8xxx_spi");
777static struct platform_driver mpc8xxx_spi_driver = {
778	.probe = plat_mpc8xxx_spi_probe,
779	.remove = plat_mpc8xxx_spi_remove,
780	.driver = {
781		.name = "mpc8xxx_spi",
782	},
783};
784
785static bool legacy_driver_failed;
786
787static void __init legacy_driver_register(void)
788{
789	legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
790}
791
792static void __exit legacy_driver_unregister(void)
793{
794	if (legacy_driver_failed)
795		return;
796	platform_driver_unregister(&mpc8xxx_spi_driver);
797}
798#else
799static void __init legacy_driver_register(void) {}
800static void __exit legacy_driver_unregister(void) {}
801#endif /* CONFIG_MPC832x_RDB */
802
803static int __init fsl_spi_init(void)
804{
805	legacy_driver_register();
806	return platform_driver_register(&of_fsl_spi_driver);
807}
808module_init(fsl_spi_init);
809
810static void __exit fsl_spi_exit(void)
811{
812	platform_driver_unregister(&of_fsl_spi_driver);
813	legacy_driver_unregister();
814}
815module_exit(fsl_spi_exit);
816
817MODULE_AUTHOR("Kumar Gala");
818MODULE_DESCRIPTION("Simple Freescale SPI Driver");
819MODULE_LICENSE("GPL");