Linux Audio

Check our new training course

Loading...
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");
v3.15
 
  1/*
  2 * Freescale SPI controller driver.
  3 *
  4 * Maintainer: Kumar Gala
  5 *
  6 * Copyright (C) 2006 Polycom, Inc.
  7 * Copyright 2010 Freescale Semiconductor, Inc.
  8 *
  9 * CPM SPI and QE buffer descriptors mode support:
 10 * Copyright (c) 2009  MontaVista Software, Inc.
 11 * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
 12 *
 13 * GRLIB support:
 14 * Copyright (c) 2012 Aeroflex Gaisler AB.
 15 * Author: Andreas Larsson <andreas@gaisler.com>
 16 *
 17 * This program is free software; you can redistribute  it and/or modify it
 18 * under  the terms of  the GNU General  Public License as published by the
 19 * Free Software Foundation;  either version 2 of the  License, or (at your
 20 * option) any later version.
 21 */
 22#include <linux/module.h>
 23#include <linux/types.h>
 24#include <linux/kernel.h>
 
 25#include <linux/interrupt.h>
 26#include <linux/delay.h>
 27#include <linux/irq.h>
 28#include <linux/spi/spi.h>
 29#include <linux/spi/spi_bitbang.h>
 30#include <linux/platform_device.h>
 31#include <linux/fsl_devices.h>
 32#include <linux/dma-mapping.h>
 33#include <linux/mm.h>
 
 34#include <linux/mutex.h>
 35#include <linux/of.h>
 36#include <linux/of_platform.h>
 37#include <linux/of_address.h>
 38#include <linux/of_irq.h>
 39#include <linux/gpio.h>
 40#include <linux/of_gpio.h>
 
 
 
 
 
 
 
 
 
 
 
 41
 42#include "spi-fsl-lib.h"
 43#include "spi-fsl-cpm.h"
 44#include "spi-fsl-spi.h"
 45
 46#define TYPE_FSL	0
 47#define TYPE_GRLIB	1
 48
 49struct fsl_spi_match_data {
 50	int type;
 51};
 52
 53static struct fsl_spi_match_data of_fsl_spi_fsl_config = {
 54	.type = TYPE_FSL,
 55};
 56
 57static struct fsl_spi_match_data of_fsl_spi_grlib_config = {
 58	.type = TYPE_GRLIB,
 59};
 60
 61static struct of_device_id of_fsl_spi_match[] = {
 62	{
 63		.compatible = "fsl,spi",
 64		.data = &of_fsl_spi_fsl_config,
 65	},
 66	{
 67		.compatible = "aeroflexgaisler,spictrl",
 68		.data = &of_fsl_spi_grlib_config,
 69	},
 70	{}
 71};
 72MODULE_DEVICE_TABLE(of, of_fsl_spi_match);
 73
 74static int fsl_spi_get_type(struct device *dev)
 75{
 76	const struct of_device_id *match;
 77
 78	if (dev->of_node) {
 79		match = of_match_node(of_fsl_spi_match, dev->of_node);
 80		if (match && match->data)
 81			return ((struct fsl_spi_match_data *)match->data)->type;
 82	}
 83	return TYPE_FSL;
 84}
 85
 86static void fsl_spi_change_mode(struct spi_device *spi)
 87{
 88	struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
 89	struct spi_mpc8xxx_cs *cs = spi->controller_state;
 90	struct fsl_spi_reg *reg_base = mspi->reg_base;
 91	__be32 __iomem *mode = &reg_base->mode;
 92	unsigned long flags;
 93
 94	if (cs->hw_mode == mpc8xxx_spi_read_reg(mode))
 95		return;
 96
 97	/* Turn off IRQs locally to minimize time that SPI is disabled. */
 98	local_irq_save(flags);
 99
100	/* Turn off SPI unit prior changing mode */
101	mpc8xxx_spi_write_reg(mode, cs->hw_mode & ~SPMODE_ENABLE);
102
103	/* When in CPM mode, we need to reinit tx and rx. */
104	if (mspi->flags & SPI_CPM_MODE) {
105		fsl_spi_cpm_reinit_txrx(mspi);
106	}
107	mpc8xxx_spi_write_reg(mode, cs->hw_mode);
108	local_irq_restore(flags);
109}
110
111static void fsl_spi_chipselect(struct spi_device *spi, int value)
112{
113	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
114	struct fsl_spi_platform_data *pdata;
115	bool pol = spi->mode & SPI_CS_HIGH;
116	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
117
118	pdata = spi->dev.parent->parent->platform_data;
119
120	if (value == BITBANG_CS_INACTIVE) {
121		if (pdata->cs_control)
122			pdata->cs_control(spi, !pol);
123	}
124
125	if (value == BITBANG_CS_ACTIVE) {
126		mpc8xxx_spi->rx_shift = cs->rx_shift;
127		mpc8xxx_spi->tx_shift = cs->tx_shift;
128		mpc8xxx_spi->get_rx = cs->get_rx;
129		mpc8xxx_spi->get_tx = cs->get_tx;
130
131		fsl_spi_change_mode(spi);
132
133		if (pdata->cs_control)
134			pdata->cs_control(spi, pol);
135	}
136}
137
138static void fsl_spi_qe_cpu_set_shifts(u32 *rx_shift, u32 *tx_shift,
139				      int bits_per_word, int msb_first)
140{
141	*rx_shift = 0;
142	*tx_shift = 0;
143	if (msb_first) {
144		if (bits_per_word <= 8) {
145			*rx_shift = 16;
146			*tx_shift = 24;
147		} else if (bits_per_word <= 16) {
148			*rx_shift = 16;
149			*tx_shift = 16;
150		}
151	} else {
152		if (bits_per_word <= 8)
153			*rx_shift = 8;
154	}
155}
156
157static void fsl_spi_grlib_set_shifts(u32 *rx_shift, u32 *tx_shift,
158				     int bits_per_word, int msb_first)
159{
160	*rx_shift = 0;
161	*tx_shift = 0;
162	if (bits_per_word <= 16) {
163		if (msb_first) {
164			*rx_shift = 16; /* LSB in bit 16 */
165			*tx_shift = 32 - bits_per_word; /* MSB in bit 31 */
166		} else {
167			*rx_shift = 16 - bits_per_word; /* MSB in bit 15 */
168		}
169	}
170}
171
172static int mspi_apply_cpu_mode_quirks(struct spi_mpc8xxx_cs *cs,
173				struct spi_device *spi,
174				struct mpc8xxx_spi *mpc8xxx_spi,
175				int bits_per_word)
176{
177	cs->rx_shift = 0;
178	cs->tx_shift = 0;
179	if (bits_per_word <= 8) {
180		cs->get_rx = mpc8xxx_spi_rx_buf_u8;
181		cs->get_tx = mpc8xxx_spi_tx_buf_u8;
182	} else if (bits_per_word <= 16) {
183		cs->get_rx = mpc8xxx_spi_rx_buf_u16;
184		cs->get_tx = mpc8xxx_spi_tx_buf_u16;
185	} else if (bits_per_word <= 32) {
186		cs->get_rx = mpc8xxx_spi_rx_buf_u32;
187		cs->get_tx = mpc8xxx_spi_tx_buf_u32;
188	} else
189		return -EINVAL;
190
191	if (mpc8xxx_spi->set_shifts)
192		mpc8xxx_spi->set_shifts(&cs->rx_shift, &cs->tx_shift,
193					bits_per_word,
194					!(spi->mode & SPI_LSB_FIRST));
195
196	mpc8xxx_spi->rx_shift = cs->rx_shift;
197	mpc8xxx_spi->tx_shift = cs->tx_shift;
198	mpc8xxx_spi->get_rx = cs->get_rx;
199	mpc8xxx_spi->get_tx = cs->get_tx;
200
201	return bits_per_word;
202}
203
204static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs,
205				struct spi_device *spi,
206				int bits_per_word)
207{
208	/* QE uses Little Endian for words > 8
209	 * so transform all words > 8 into 8 bits
210	 * Unfortnatly that doesn't work for LSB so
211	 * reject these for now */
212	/* Note: 32 bits word, LSB works iff
213	 * tfcr/rfcr is set to CPMFCR_GBL */
214	if (spi->mode & SPI_LSB_FIRST &&
215	    bits_per_word > 8)
216		return -EINVAL;
217	if (bits_per_word > 8)
218		return 8; /* pretend its 8 bits */
219	return bits_per_word;
220}
221
222static int fsl_spi_setup_transfer(struct spi_device *spi,
223					struct spi_transfer *t)
224{
225	struct mpc8xxx_spi *mpc8xxx_spi;
226	int bits_per_word = 0;
227	u8 pm;
228	u32 hz = 0;
229	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
230
231	mpc8xxx_spi = spi_master_get_devdata(spi->master);
232
233	if (t) {
234		bits_per_word = t->bits_per_word;
235		hz = t->speed_hz;
236	}
237
238	/* spi_transfer level calls that work per-word */
239	if (!bits_per_word)
240		bits_per_word = spi->bits_per_word;
241
242	if (!hz)
243		hz = spi->max_speed_hz;
244
245	if (!(mpc8xxx_spi->flags & SPI_CPM_MODE))
246		bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi,
247							   mpc8xxx_spi,
248							   bits_per_word);
249	else if (mpc8xxx_spi->flags & SPI_QE)
250		bits_per_word = mspi_apply_qe_mode_quirks(cs, spi,
251							  bits_per_word);
252
253	if (bits_per_word < 0)
254		return bits_per_word;
255
256	if (bits_per_word == 32)
257		bits_per_word = 0;
258	else
259		bits_per_word = bits_per_word - 1;
260
261	/* mask out bits we are going to set */
262	cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16
263				  | SPMODE_PM(0xF));
264
265	cs->hw_mode |= SPMODE_LEN(bits_per_word);
266
267	if ((mpc8xxx_spi->spibrg / hz) > 64) {
268		cs->hw_mode |= SPMODE_DIV16;
269		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
270
271		WARN_ONCE(pm > 16, "%s: Requested speed is too low: %d Hz. "
272			  "Will use %d Hz instead.\n", dev_name(&spi->dev),
273			  hz, mpc8xxx_spi->spibrg / 1024);
274		if (pm > 16)
275			pm = 16;
276	} else {
277		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
278	}
279	if (pm)
280		pm--;
281
282	cs->hw_mode |= SPMODE_PM(pm);
283
284	fsl_spi_change_mode(spi);
285	return 0;
286}
287
288static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi,
289				struct spi_transfer *t, unsigned int len)
290{
291	u32 word;
292	struct fsl_spi_reg *reg_base = mspi->reg_base;
293
294	mspi->count = len;
295
296	/* enable rx ints */
297	mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
298
299	/* transmit word */
300	word = mspi->get_tx(mspi);
301	mpc8xxx_spi_write_reg(&reg_base->transmit, word);
302
303	return 0;
304}
305
306static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t,
307			    bool is_dma_mapped)
308{
309	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
310	struct fsl_spi_reg *reg_base;
311	unsigned int len = t->len;
312	u8 bits_per_word;
313	int ret;
314
315	reg_base = mpc8xxx_spi->reg_base;
316	bits_per_word = spi->bits_per_word;
317	if (t->bits_per_word)
318		bits_per_word = t->bits_per_word;
319
320	if (bits_per_word > 8) {
321		/* invalid length? */
322		if (len & 1)
323			return -EINVAL;
324		len /= 2;
325	}
326	if (bits_per_word > 16) {
327		/* invalid length? */
328		if (len & 1)
329			return -EINVAL;
330		len /= 2;
331	}
332
333	mpc8xxx_spi->tx = t->tx_buf;
334	mpc8xxx_spi->rx = t->rx_buf;
335
336	reinit_completion(&mpc8xxx_spi->done);
337
338	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
339		ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped);
340	else
341		ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len);
342	if (ret)
343		return ret;
344
345	wait_for_completion(&mpc8xxx_spi->done);
346
347	/* disable rx ints */
348	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
349
350	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
351		fsl_spi_cpm_bufs_complete(mpc8xxx_spi);
352
353	return mpc8xxx_spi->count;
354}
355
356static void fsl_spi_do_one_msg(struct spi_message *m)
 
357{
358	struct spi_device *spi = m->spi;
359	struct spi_transfer *t, *first;
360	unsigned int cs_change;
361	const int nsecs = 50;
362	int status;
363
364	/* Don't allow changes if CS is active */
365	first = list_first_entry(&m->transfers, struct spi_transfer,
366			transfer_list);
367	list_for_each_entry(t, &m->transfers, transfer_list) {
368		if ((first->bits_per_word != t->bits_per_word) ||
369			(first->speed_hz != t->speed_hz)) {
370			status = -EINVAL;
371			dev_err(&spi->dev,
372				"bits_per_word/speed_hz should be same for the same SPI transfer\n");
373			return;
374		}
375	}
376
377	cs_change = 1;
378	status = -EINVAL;
 
 
 
 
 
 
379	list_for_each_entry(t, &m->transfers, transfer_list) {
380		if (t->bits_per_word || t->speed_hz) {
381			if (cs_change)
382				status = fsl_spi_setup_transfer(spi, t);
383			if (status < 0)
384				break;
385		}
386
387		if (cs_change) {
388			fsl_spi_chipselect(spi, BITBANG_CS_ACTIVE);
389			ndelay(nsecs);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
390		}
391		cs_change = t->cs_change;
392		if (t->len)
393			status = fsl_spi_bufs(spi, t, m->is_dma_mapped);
394		if (status) {
395			status = -EMSGSIZE;
396			break;
397		}
398		m->actual_length += t->len;
399
400		if (t->delay_usecs)
401			udelay(t->delay_usecs);
 
 
 
402
403		if (cs_change) {
404			ndelay(nsecs);
405			fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
406			ndelay(nsecs);
407		}
408	}
 
409
410	m->status = status;
411	if (m->complete)
412		m->complete(m->context);
413
414	if (status || !cs_change) {
415		ndelay(nsecs);
416		fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
417	}
418
419	fsl_spi_setup_transfer(spi, NULL);
420}
421
422static int fsl_spi_setup(struct spi_device *spi)
423{
424	struct mpc8xxx_spi *mpc8xxx_spi;
425	struct fsl_spi_reg *reg_base;
 
426	int retval;
427	u32 hw_mode;
428	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
429
430	if (!spi->max_speed_hz)
431		return -EINVAL;
432
433	if (!cs) {
434		cs = kzalloc(sizeof *cs, GFP_KERNEL);
435		if (!cs)
436			return -ENOMEM;
437		spi->controller_state = cs;
 
438	}
439	mpc8xxx_spi = spi_master_get_devdata(spi->master);
440
441	reg_base = mpc8xxx_spi->reg_base;
442
443	hw_mode = cs->hw_mode; /* Save original settings */
444	cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
445	/* mask out bits we are going to set */
446	cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
447			 | SPMODE_REV | SPMODE_LOOP);
448
449	if (spi->mode & SPI_CPHA)
450		cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
451	if (spi->mode & SPI_CPOL)
452		cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
453	if (!(spi->mode & SPI_LSB_FIRST))
454		cs->hw_mode |= SPMODE_REV;
455	if (spi->mode & SPI_LOOP)
456		cs->hw_mode |= SPMODE_LOOP;
457
458	retval = fsl_spi_setup_transfer(spi, NULL);
459	if (retval < 0) {
460		cs->hw_mode = hw_mode; /* Restore settings */
 
 
461		return retval;
462	}
463
464	if (mpc8xxx_spi->type == TYPE_GRLIB) {
465		if (gpio_is_valid(spi->cs_gpio)) {
466			int desel;
467
468			retval = gpio_request(spi->cs_gpio,
469					      dev_name(&spi->dev));
470			if (retval)
471				return retval;
472
473			desel = !(spi->mode & SPI_CS_HIGH);
474			retval = gpio_direction_output(spi->cs_gpio, desel);
475			if (retval) {
476				gpio_free(spi->cs_gpio);
477				return retval;
478			}
479		} else if (spi->cs_gpio != -ENOENT) {
480			if (spi->cs_gpio < 0)
481				return spi->cs_gpio;
482			return -EINVAL;
483		}
484		/* When spi->cs_gpio == -ENOENT, a hole in the phandle list
485		 * indicates to use native chipselect if present, or allow for
486		 * an always selected chip
487		 */
488	}
489
490	/* Initialize chipselect - might be active for SPI_CS_HIGH mode */
491	fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
492
493	return 0;
494}
495
496static void fsl_spi_cleanup(struct spi_device *spi)
497{
498	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
499
500	if (mpc8xxx_spi->type == TYPE_GRLIB && gpio_is_valid(spi->cs_gpio))
501		gpio_free(spi->cs_gpio);
502}
503
504static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
505{
506	struct fsl_spi_reg *reg_base = mspi->reg_base;
507
508	/* We need handle RX first */
509	if (events & SPIE_NE) {
510		u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
511
512		if (mspi->rx)
513			mspi->get_rx(rx_data, mspi);
514	}
515
516	if ((events & SPIE_NF) == 0)
517		/* spin until TX is done */
518		while (((events =
519			mpc8xxx_spi_read_reg(&reg_base->event)) &
520						SPIE_NF) == 0)
521			cpu_relax();
522
523	/* Clear the events */
524	mpc8xxx_spi_write_reg(&reg_base->event, events);
525
526	mspi->count -= 1;
527	if (mspi->count) {
528		u32 word = mspi->get_tx(mspi);
529
530		mpc8xxx_spi_write_reg(&reg_base->transmit, word);
531	} else {
532		complete(&mspi->done);
533	}
534}
535
536static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
537{
538	struct mpc8xxx_spi *mspi = context_data;
539	irqreturn_t ret = IRQ_NONE;
540	u32 events;
541	struct fsl_spi_reg *reg_base = mspi->reg_base;
542
543	/* Get interrupt events(tx/rx) */
544	events = mpc8xxx_spi_read_reg(&reg_base->event);
545	if (events)
546		ret = IRQ_HANDLED;
547
548	dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
549
550	if (mspi->flags & SPI_CPM_MODE)
551		fsl_spi_cpm_irq(mspi, events);
552	else
553		fsl_spi_cpu_irq(mspi, events);
554
555	return ret;
556}
557
558static void fsl_spi_remove(struct mpc8xxx_spi *mspi)
559{
560	iounmap(mspi->reg_base);
561	fsl_spi_cpm_free(mspi);
562}
563
564static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on)
565{
566	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
567	struct fsl_spi_reg *reg_base = mpc8xxx_spi->reg_base;
568	u32 slvsel;
569	u16 cs = spi->chip_select;
570
571	if (gpio_is_valid(spi->cs_gpio)) {
572		gpio_set_value(spi->cs_gpio, on);
573	} else if (cs < mpc8xxx_spi->native_chipselects) {
574		slvsel = mpc8xxx_spi_read_reg(&reg_base->slvsel);
575		slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs));
576		mpc8xxx_spi_write_reg(&reg_base->slvsel, slvsel);
577	}
578}
579
580static void fsl_spi_grlib_probe(struct device *dev)
581{
582	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
583	struct spi_master *master = dev_get_drvdata(dev);
584	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
585	struct fsl_spi_reg *reg_base = mpc8xxx_spi->reg_base;
586	int mbits;
587	u32 capabilities;
588
589	capabilities = mpc8xxx_spi_read_reg(&reg_base->cap);
590
591	mpc8xxx_spi->set_shifts = fsl_spi_grlib_set_shifts;
592	mbits = SPCAP_MAXWLEN(capabilities);
593	if (mbits)
594		mpc8xxx_spi->max_bits_per_word = mbits + 1;
595
596	mpc8xxx_spi->native_chipselects = 0;
597	if (SPCAP_SSEN(capabilities)) {
598		mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities);
599		mpc8xxx_spi_write_reg(&reg_base->slvsel, 0xffffffff);
600	}
601	master->num_chipselect = mpc8xxx_spi->native_chipselects;
602	pdata->cs_control = fsl_spi_grlib_cs_control;
603}
604
605static struct spi_master * fsl_spi_probe(struct device *dev,
 
 
 
 
 
 
 
 
 
 
 
606		struct resource *mem, unsigned int irq)
607{
608	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
609	struct spi_master *master;
610	struct mpc8xxx_spi *mpc8xxx_spi;
611	struct fsl_spi_reg *reg_base;
612	u32 regval;
613	int ret = 0;
614
615	master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
616	if (master == NULL) {
617		ret = -ENOMEM;
618		goto err;
619	}
620
621	dev_set_drvdata(dev, master);
622
623	ret = mpc8xxx_spi_probe(dev, mem, irq);
624	if (ret)
625		goto err_probe;
626
627	master->setup = fsl_spi_setup;
628	master->cleanup = fsl_spi_cleanup;
 
 
 
 
 
629
630	mpc8xxx_spi = spi_master_get_devdata(master);
631	mpc8xxx_spi->spi_do_one_msg = fsl_spi_do_one_msg;
632	mpc8xxx_spi->spi_remove = fsl_spi_remove;
633	mpc8xxx_spi->max_bits_per_word = 32;
634	mpc8xxx_spi->type = fsl_spi_get_type(dev);
635
636	ret = fsl_spi_cpm_init(mpc8xxx_spi);
637	if (ret)
638		goto err_cpm_init;
639
640	mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem));
641	if (mpc8xxx_spi->reg_base == NULL) {
642		ret = -ENOMEM;
643		goto err_ioremap;
644	}
645
646	if (mpc8xxx_spi->type == TYPE_GRLIB)
647		fsl_spi_grlib_probe(dev);
648
649	master->bits_per_word_mask =
650		(SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32)) &
 
 
 
 
 
 
651		SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word);
652
653	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
654		mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts;
655
656	if (mpc8xxx_spi->set_shifts)
657		/* 8 bits per word and MSB first */
658		mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift,
659					&mpc8xxx_spi->tx_shift, 8, 1);
660
661	/* Register for SPI Interrupt */
662	ret = request_irq(mpc8xxx_spi->irq, fsl_spi_irq,
663			  0, "fsl_spi", mpc8xxx_spi);
664
665	if (ret != 0)
666		goto free_irq;
667
668	reg_base = mpc8xxx_spi->reg_base;
669
670	/* SPI controller initializations */
671	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
672	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
673	mpc8xxx_spi_write_reg(&reg_base->command, 0);
674	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
675
676	/* Enable SPI interface */
677	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
678	if (mpc8xxx_spi->max_bits_per_word < 8) {
679		regval &= ~SPMODE_LEN(0xF);
680		regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1);
681	}
682	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
683		regval |= SPMODE_OP;
684
685	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
686
687	ret = spi_register_master(master);
688	if (ret < 0)
689		goto unreg_master;
690
691	dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
692		 mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
693
694	return master;
695
696unreg_master:
697	free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
698free_irq:
699	iounmap(mpc8xxx_spi->reg_base);
700err_ioremap:
701	fsl_spi_cpm_free(mpc8xxx_spi);
702err_cpm_init:
703err_probe:
704	spi_master_put(master);
705err:
706	return ERR_PTR(ret);
707}
708
709static void fsl_spi_cs_control(struct spi_device *spi, bool on)
710{
711	struct device *dev = spi->dev.parent->parent;
712	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
713	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
714	u16 cs = spi->chip_select;
715	int gpio = pinfo->gpios[cs];
716	bool alow = pinfo->alow_flags[cs];
717
718	gpio_set_value(gpio, on ^ alow);
719}
720
721static int of_fsl_spi_get_chipselects(struct device *dev)
722{
723	struct device_node *np = dev->of_node;
724	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
725	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
726	int ngpios;
727	int i = 0;
728	int ret;
729
730	ngpios = of_gpio_count(np);
731	if (ngpios <= 0) {
732		/*
733		 * SPI w/o chip-select line. One SPI device is still permitted
734		 * though.
735		 */
736		pdata->max_chipselect = 1;
737		return 0;
738	}
739
740	pinfo->gpios = kmalloc(ngpios * sizeof(*pinfo->gpios), GFP_KERNEL);
741	if (!pinfo->gpios)
742		return -ENOMEM;
743	memset(pinfo->gpios, -1, ngpios * sizeof(*pinfo->gpios));
744
745	pinfo->alow_flags = kzalloc(ngpios * sizeof(*pinfo->alow_flags),
746				    GFP_KERNEL);
747	if (!pinfo->alow_flags) {
748		ret = -ENOMEM;
749		goto err_alloc_flags;
750	}
751
752	for (; i < ngpios; i++) {
753		int gpio;
754		enum of_gpio_flags flags;
755
756		gpio = of_get_gpio_flags(np, i, &flags);
757		if (!gpio_is_valid(gpio)) {
758			dev_err(dev, "invalid gpio #%d: %d\n", i, gpio);
759			ret = gpio;
760			goto err_loop;
761		}
762
763		ret = gpio_request(gpio, dev_name(dev));
764		if (ret) {
765			dev_err(dev, "can't request gpio #%d: %d\n", i, ret);
766			goto err_loop;
767		}
768
769		pinfo->gpios[i] = gpio;
770		pinfo->alow_flags[i] = flags & OF_GPIO_ACTIVE_LOW;
771
772		ret = gpio_direction_output(pinfo->gpios[i],
773					    pinfo->alow_flags[i]);
774		if (ret) {
775			dev_err(dev, "can't set output direction for gpio "
776				"#%d: %d\n", i, ret);
777			goto err_loop;
778		}
779	}
780
781	pdata->max_chipselect = ngpios;
782	pdata->cs_control = fsl_spi_cs_control;
783
784	return 0;
785
786err_loop:
787	while (i >= 0) {
788		if (gpio_is_valid(pinfo->gpios[i]))
789			gpio_free(pinfo->gpios[i]);
790		i--;
791	}
792
793	kfree(pinfo->alow_flags);
794	pinfo->alow_flags = NULL;
795err_alloc_flags:
796	kfree(pinfo->gpios);
797	pinfo->gpios = NULL;
798	return ret;
799}
800
801static int of_fsl_spi_free_chipselects(struct device *dev)
802{
803	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
804	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
805	int i;
806
807	if (!pinfo->gpios)
808		return 0;
809
810	for (i = 0; i < pdata->max_chipselect; i++) {
811		if (gpio_is_valid(pinfo->gpios[i]))
812			gpio_free(pinfo->gpios[i]);
813	}
814
815	kfree(pinfo->gpios);
816	kfree(pinfo->alow_flags);
817	return 0;
818}
819
820static int of_fsl_spi_probe(struct platform_device *ofdev)
821{
822	struct device *dev = &ofdev->dev;
823	struct device_node *np = ofdev->dev.of_node;
824	struct spi_master *master;
825	struct resource mem;
826	int irq, type;
827	int ret = -ENOMEM;
 
 
 
 
 
828
829	ret = of_mpc8xxx_spi_probe(ofdev);
830	if (ret)
831		return ret;
832
833	type = fsl_spi_get_type(&ofdev->dev);
834	if (type == TYPE_FSL) {
835		ret = of_fsl_spi_get_chipselects(dev);
836		if (ret)
837			goto err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
838	}
839
840	ret = of_address_to_resource(np, 0, &mem);
841	if (ret)
842		goto err;
843
844	irq = irq_of_parse_and_map(np, 0);
845	if (!irq) {
846		ret = -EINVAL;
847		goto err;
848	}
849
850	master = fsl_spi_probe(dev, &mem, irq);
851	if (IS_ERR(master)) {
852		ret = PTR_ERR(master);
853		goto err;
854	}
855
856	return 0;
857
858err:
859	if (type == TYPE_FSL)
860		of_fsl_spi_free_chipselects(dev);
 
 
861	return ret;
862}
863
864static int of_fsl_spi_remove(struct platform_device *ofdev)
865{
866	struct spi_master *master = platform_get_drvdata(ofdev);
867	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
868	int ret;
869
870	ret = mpc8xxx_spi_remove(&ofdev->dev);
871	if (ret)
872		return ret;
873	if (mpc8xxx_spi->type == TYPE_FSL)
874		of_fsl_spi_free_chipselects(&ofdev->dev);
875	return 0;
876}
877
878static struct platform_driver of_fsl_spi_driver = {
879	.driver = {
880		.name = "fsl_spi",
881		.owner = THIS_MODULE,
882		.of_match_table = of_fsl_spi_match,
883	},
884	.probe		= of_fsl_spi_probe,
885	.remove		= of_fsl_spi_remove,
886};
887
888#ifdef CONFIG_MPC832x_RDB
889/*
890 * XXX XXX XXX
891 * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
892 * only. The driver should go away soon, since newer MPC8323E-RDB's device
893 * tree can work with OpenFirmware driver. But for now we support old trees
894 * as well.
895 */
896static int plat_mpc8xxx_spi_probe(struct platform_device *pdev)
897{
898	struct resource *mem;
899	int irq;
900	struct spi_master *master;
901
902	if (!dev_get_platdata(&pdev->dev))
903		return -EINVAL;
904
905	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
906	if (!mem)
907		return -EINVAL;
908
909	irq = platform_get_irq(pdev, 0);
910	if (irq <= 0)
911		return -EINVAL;
912
913	master = fsl_spi_probe(&pdev->dev, mem, irq);
914	return PTR_ERR_OR_ZERO(master);
915}
916
917static int plat_mpc8xxx_spi_remove(struct platform_device *pdev)
918{
919	return mpc8xxx_spi_remove(&pdev->dev);
 
 
 
920}
921
922MODULE_ALIAS("platform:mpc8xxx_spi");
923static struct platform_driver mpc8xxx_spi_driver = {
924	.probe = plat_mpc8xxx_spi_probe,
925	.remove = plat_mpc8xxx_spi_remove,
926	.driver = {
927		.name = "mpc8xxx_spi",
928		.owner = THIS_MODULE,
929	},
930};
931
932static bool legacy_driver_failed;
933
934static void __init legacy_driver_register(void)
935{
936	legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
937}
938
939static void __exit legacy_driver_unregister(void)
940{
941	if (legacy_driver_failed)
942		return;
943	platform_driver_unregister(&mpc8xxx_spi_driver);
944}
945#else
946static void __init legacy_driver_register(void) {}
947static void __exit legacy_driver_unregister(void) {}
948#endif /* CONFIG_MPC832x_RDB */
949
950static int __init fsl_spi_init(void)
951{
952	legacy_driver_register();
953	return platform_driver_register(&of_fsl_spi_driver);
954}
955module_init(fsl_spi_init);
956
957static void __exit fsl_spi_exit(void)
958{
959	platform_driver_unregister(&of_fsl_spi_driver);
960	legacy_driver_unregister();
961}
962module_exit(fsl_spi_exit);
963
964MODULE_AUTHOR("Kumar Gala");
965MODULE_DESCRIPTION("Simple Freescale SPI Driver");
966MODULE_LICENSE("GPL");