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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");
v4.17
 
  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/delay.h>
 23#include <linux/dma-mapping.h>
 24#include <linux/fsl_devices.h>
 25#include <linux/gpio.h>
 26#include <linux/interrupt.h>
 27#include <linux/irq.h>
 28#include <linux/kernel.h>
 29#include <linux/mm.h>
 30#include <linux/module.h>
 31#include <linux/mutex.h>
 32#include <linux/of.h>
 33#include <linux/of_address.h>
 34#include <linux/of_irq.h>
 35#include <linux/of_gpio.h>
 36#include <linux/of_platform.h>
 37#include <linux/platform_device.h>
 38#include <linux/spi/spi.h>
 39#include <linux/spi/spi_bitbang.h>
 40#include <linux/types.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 const 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		WARN_ONCE(pm > 16,
271			  "%s: Requested speed is too low: %d Hz. Will use %d Hz instead.\n",
272			  dev_name(&spi->dev), hz, mpc8xxx_spi->spibrg / 1024);
273		if (pm > 16)
274			pm = 16;
275	} else {
276		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
277	}
278	if (pm)
279		pm--;
280
281	cs->hw_mode |= SPMODE_PM(pm);
282
283	fsl_spi_change_mode(spi);
284	return 0;
285}
286
287static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi,
288				struct spi_transfer *t, unsigned int len)
289{
290	u32 word;
291	struct fsl_spi_reg *reg_base = mspi->reg_base;
292
293	mspi->count = len;
294
295	/* enable rx ints */
296	mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
297
298	/* transmit word */
299	word = mspi->get_tx(mspi);
300	mpc8xxx_spi_write_reg(&reg_base->transmit, word);
301
302	return 0;
303}
304
305static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t,
306			    bool is_dma_mapped)
307{
308	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
309	struct fsl_spi_reg *reg_base;
310	unsigned int len = t->len;
311	u8 bits_per_word;
312	int ret;
313
314	reg_base = mpc8xxx_spi->reg_base;
315	bits_per_word = spi->bits_per_word;
316	if (t->bits_per_word)
317		bits_per_word = t->bits_per_word;
318
319	if (bits_per_word > 8) {
320		/* invalid length? */
321		if (len & 1)
322			return -EINVAL;
323		len /= 2;
324	}
325	if (bits_per_word > 16) {
326		/* invalid length? */
327		if (len & 1)
328			return -EINVAL;
329		len /= 2;
330	}
331
332	mpc8xxx_spi->tx = t->tx_buf;
333	mpc8xxx_spi->rx = t->rx_buf;
334
335	reinit_completion(&mpc8xxx_spi->done);
336
337	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
338		ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped);
339	else
340		ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len);
341	if (ret)
342		return ret;
343
344	wait_for_completion(&mpc8xxx_spi->done);
345
346	/* disable rx ints */
347	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
348
349	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
350		fsl_spi_cpm_bufs_complete(mpc8xxx_spi);
351
352	return mpc8xxx_spi->count;
353}
354
355static int fsl_spi_do_one_msg(struct spi_master *master,
356			      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			dev_err(&spi->dev,
371				"bits_per_word/speed_hz should be same for the same SPI transfer\n");
372			return -EINVAL;
373		}
 
 
 
 
 
 
 
 
374	}
 
 
375
376	cs_change = 1;
377	status = -EINVAL;
378	list_for_each_entry(t, &m->transfers, transfer_list) {
379		if (t->bits_per_word || t->speed_hz) {
380			if (cs_change)
381				status = fsl_spi_setup_transfer(spi, t);
382			if (status < 0)
383				break;
384		}
385
386		if (cs_change) {
387			fsl_spi_chipselect(spi, BITBANG_CS_ACTIVE);
388			ndelay(nsecs);
389		}
390		cs_change = t->cs_change;
391		if (t->len)
392			status = fsl_spi_bufs(spi, t, m->is_dma_mapped);
393		if (status) {
394			status = -EMSGSIZE;
395			break;
396		}
397		m->actual_length += t->len;
398
399		if (t->delay_usecs)
400			udelay(t->delay_usecs);
401
402		if (cs_change) {
403			ndelay(nsecs);
404			fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
405			ndelay(nsecs);
406		}
407	}
408
409	m->status = status;
410	spi_finalize_current_message(master);
411
412	if (status || !cs_change) {
413		ndelay(nsecs);
414		fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
415	}
416
417	fsl_spi_setup_transfer(spi, NULL);
418	return 0;
419}
420
421static int fsl_spi_setup(struct spi_device *spi)
422{
423	struct mpc8xxx_spi *mpc8xxx_spi;
424	struct fsl_spi_reg *reg_base;
 
425	int retval;
426	u32 hw_mode;
427	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
428
429	if (!spi->max_speed_hz)
430		return -EINVAL;
431
432	if (!cs) {
433		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
434		if (!cs)
435			return -ENOMEM;
436		spi_set_ctldata(spi, cs);
 
437	}
438	mpc8xxx_spi = spi_master_get_devdata(spi->master);
439
440	reg_base = mpc8xxx_spi->reg_base;
441
442	hw_mode = cs->hw_mode; /* Save original settings */
443	cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
444	/* mask out bits we are going to set */
445	cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
446			 | SPMODE_REV | SPMODE_LOOP);
447
448	if (spi->mode & SPI_CPHA)
449		cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
450	if (spi->mode & SPI_CPOL)
451		cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
452	if (!(spi->mode & SPI_LSB_FIRST))
453		cs->hw_mode |= SPMODE_REV;
454	if (spi->mode & SPI_LOOP)
455		cs->hw_mode |= SPMODE_LOOP;
456
457	retval = fsl_spi_setup_transfer(spi, NULL);
458	if (retval < 0) {
459		cs->hw_mode = hw_mode; /* Restore settings */
 
 
460		return retval;
461	}
462
463	if (mpc8xxx_spi->type == TYPE_GRLIB) {
464		if (gpio_is_valid(spi->cs_gpio)) {
465			int desel;
466
467			retval = gpio_request(spi->cs_gpio,
468					      dev_name(&spi->dev));
469			if (retval)
470				return retval;
471
472			desel = !(spi->mode & SPI_CS_HIGH);
473			retval = gpio_direction_output(spi->cs_gpio, desel);
474			if (retval) {
475				gpio_free(spi->cs_gpio);
476				return retval;
477			}
478		} else if (spi->cs_gpio != -ENOENT) {
479			if (spi->cs_gpio < 0)
480				return spi->cs_gpio;
481			return -EINVAL;
482		}
483		/* When spi->cs_gpio == -ENOENT, a hole in the phandle list
484		 * indicates to use native chipselect if present, or allow for
485		 * an always selected chip
486		 */
487	}
488
489	/* Initialize chipselect - might be active for SPI_CS_HIGH mode */
490	fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
491
492	return 0;
493}
494
495static void fsl_spi_cleanup(struct spi_device *spi)
496{
497	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
498	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
499
500	if (mpc8xxx_spi->type == TYPE_GRLIB && gpio_is_valid(spi->cs_gpio))
501		gpio_free(spi->cs_gpio);
502
503	kfree(cs);
504	spi_set_ctldata(spi, NULL);
505}
506
507static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
508{
509	struct fsl_spi_reg *reg_base = mspi->reg_base;
510
511	/* We need handle RX first */
512	if (events & SPIE_NE) {
513		u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
514
515		if (mspi->rx)
516			mspi->get_rx(rx_data, mspi);
517	}
518
519	if ((events & SPIE_NF) == 0)
520		/* spin until TX is done */
521		while (((events =
522			mpc8xxx_spi_read_reg(&reg_base->event)) &
523						SPIE_NF) == 0)
524			cpu_relax();
525
526	/* Clear the events */
527	mpc8xxx_spi_write_reg(&reg_base->event, events);
528
529	mspi->count -= 1;
530	if (mspi->count) {
531		u32 word = mspi->get_tx(mspi);
532
533		mpc8xxx_spi_write_reg(&reg_base->transmit, word);
534	} else {
535		complete(&mspi->done);
536	}
537}
538
539static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
540{
541	struct mpc8xxx_spi *mspi = context_data;
542	irqreturn_t ret = IRQ_NONE;
543	u32 events;
544	struct fsl_spi_reg *reg_base = mspi->reg_base;
545
546	/* Get interrupt events(tx/rx) */
547	events = mpc8xxx_spi_read_reg(&reg_base->event);
548	if (events)
549		ret = IRQ_HANDLED;
550
551	dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
552
553	if (mspi->flags & SPI_CPM_MODE)
554		fsl_spi_cpm_irq(mspi, events);
555	else
556		fsl_spi_cpu_irq(mspi, events);
557
558	return ret;
559}
560
561static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on)
562{
563	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
564	struct fsl_spi_reg *reg_base = mpc8xxx_spi->reg_base;
565	u32 slvsel;
566	u16 cs = spi->chip_select;
567
568	if (gpio_is_valid(spi->cs_gpio)) {
569		gpio_set_value(spi->cs_gpio, on);
570	} else if (cs < mpc8xxx_spi->native_chipselects) {
571		slvsel = mpc8xxx_spi_read_reg(&reg_base->slvsel);
572		slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs));
573		mpc8xxx_spi_write_reg(&reg_base->slvsel, slvsel);
574	}
575}
576
577static void fsl_spi_grlib_probe(struct device *dev)
578{
579	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
580	struct spi_master *master = dev_get_drvdata(dev);
581	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
582	struct fsl_spi_reg *reg_base = mpc8xxx_spi->reg_base;
583	int mbits;
584	u32 capabilities;
585
586	capabilities = mpc8xxx_spi_read_reg(&reg_base->cap);
587
588	mpc8xxx_spi->set_shifts = fsl_spi_grlib_set_shifts;
589	mbits = SPCAP_MAXWLEN(capabilities);
590	if (mbits)
591		mpc8xxx_spi->max_bits_per_word = mbits + 1;
592
593	mpc8xxx_spi->native_chipselects = 0;
594	if (SPCAP_SSEN(capabilities)) {
595		mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities);
596		mpc8xxx_spi_write_reg(&reg_base->slvsel, 0xffffffff);
597	}
598	master->num_chipselect = mpc8xxx_spi->native_chipselects;
599	pdata->cs_control = fsl_spi_grlib_cs_control;
600}
601
602static struct spi_master * fsl_spi_probe(struct device *dev,
 
 
 
 
 
 
 
 
 
 
 
603		struct resource *mem, unsigned int irq)
604{
605	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
606	struct spi_master *master;
607	struct mpc8xxx_spi *mpc8xxx_spi;
608	struct fsl_spi_reg *reg_base;
609	u32 regval;
610	int ret = 0;
611
612	master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
613	if (master == NULL) {
614		ret = -ENOMEM;
615		goto err;
616	}
617
618	dev_set_drvdata(dev, master);
619
620	mpc8xxx_spi_probe(dev, mem, irq);
621
622	master->setup = fsl_spi_setup;
623	master->cleanup = fsl_spi_cleanup;
624	master->transfer_one_message = fsl_spi_do_one_msg;
 
 
 
 
625
626	mpc8xxx_spi = spi_master_get_devdata(master);
627	mpc8xxx_spi->max_bits_per_word = 32;
628	mpc8xxx_spi->type = fsl_spi_get_type(dev);
629
630	ret = fsl_spi_cpm_init(mpc8xxx_spi);
631	if (ret)
632		goto err_cpm_init;
633
634	mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem);
635	if (IS_ERR(mpc8xxx_spi->reg_base)) {
636		ret = PTR_ERR(mpc8xxx_spi->reg_base);
637		goto err_probe;
638	}
639
640	if (mpc8xxx_spi->type == TYPE_GRLIB)
641		fsl_spi_grlib_probe(dev);
642
643	master->bits_per_word_mask =
644		(SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32)) &
645		SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word);
646
647	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
648		mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts;
649
650	if (mpc8xxx_spi->set_shifts)
651		/* 8 bits per word and MSB first */
652		mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift,
653					&mpc8xxx_spi->tx_shift, 8, 1);
654
655	/* Register for SPI Interrupt */
656	ret = devm_request_irq(dev, mpc8xxx_spi->irq, fsl_spi_irq,
657			       0, "fsl_spi", mpc8xxx_spi);
658
659	if (ret != 0)
660		goto err_probe;
661
662	reg_base = mpc8xxx_spi->reg_base;
663
664	/* SPI controller initializations */
665	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
666	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
667	mpc8xxx_spi_write_reg(&reg_base->command, 0);
668	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
669
670	/* Enable SPI interface */
671	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
672	if (mpc8xxx_spi->max_bits_per_word < 8) {
673		regval &= ~SPMODE_LEN(0xF);
674		regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1);
675	}
676	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
677		regval |= SPMODE_OP;
678
679	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
680
681	ret = devm_spi_register_master(dev, master);
682	if (ret < 0)
683		goto err_probe;
684
685	dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
686		 mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
687
688	return master;
689
690err_probe:
691	fsl_spi_cpm_free(mpc8xxx_spi);
692err_cpm_init:
693	spi_master_put(master);
694err:
695	return ERR_PTR(ret);
696}
697
698static void fsl_spi_cs_control(struct spi_device *spi, bool on)
699{
700	struct device *dev = spi->dev.parent->parent;
701	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
702	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
703	u16 cs = spi->chip_select;
704	int gpio = pinfo->gpios[cs];
705	bool alow = pinfo->alow_flags[cs];
706
707	gpio_set_value(gpio, on ^ alow);
708}
709
710static int of_fsl_spi_get_chipselects(struct device *dev)
711{
712	struct device_node *np = dev->of_node;
713	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
714	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
715	int ngpios;
716	int i = 0;
717	int ret;
718
719	ngpios = of_gpio_count(np);
720	if (ngpios <= 0) {
721		/*
722		 * SPI w/o chip-select line. One SPI device is still permitted
723		 * though.
724		 */
725		pdata->max_chipselect = 1;
726		return 0;
727	}
728
729	pinfo->gpios = kmalloc_array(ngpios, sizeof(*pinfo->gpios),
730				     GFP_KERNEL);
731	if (!pinfo->gpios)
732		return -ENOMEM;
733	memset(pinfo->gpios, -1, ngpios * sizeof(*pinfo->gpios));
734
735	pinfo->alow_flags = kcalloc(ngpios, sizeof(*pinfo->alow_flags),
736				    GFP_KERNEL);
737	if (!pinfo->alow_flags) {
738		ret = -ENOMEM;
739		goto err_alloc_flags;
740	}
741
742	for (; i < ngpios; i++) {
743		int gpio;
744		enum of_gpio_flags flags;
745
746		gpio = of_get_gpio_flags(np, i, &flags);
747		if (!gpio_is_valid(gpio)) {
748			dev_err(dev, "invalid gpio #%d: %d\n", i, gpio);
749			ret = gpio;
750			goto err_loop;
751		}
752
753		ret = gpio_request(gpio, dev_name(dev));
754		if (ret) {
755			dev_err(dev, "can't request gpio #%d: %d\n", i, ret);
756			goto err_loop;
757		}
758
759		pinfo->gpios[i] = gpio;
760		pinfo->alow_flags[i] = flags & OF_GPIO_ACTIVE_LOW;
761
762		ret = gpio_direction_output(pinfo->gpios[i],
763					    pinfo->alow_flags[i]);
764		if (ret) {
765			dev_err(dev,
766				"can't set output direction for gpio #%d: %d\n",
767				i, ret);
768			goto err_loop;
769		}
770	}
771
772	pdata->max_chipselect = ngpios;
773	pdata->cs_control = fsl_spi_cs_control;
774
775	return 0;
776
777err_loop:
778	while (i >= 0) {
779		if (gpio_is_valid(pinfo->gpios[i]))
780			gpio_free(pinfo->gpios[i]);
781		i--;
782	}
783
784	kfree(pinfo->alow_flags);
785	pinfo->alow_flags = NULL;
786err_alloc_flags:
787	kfree(pinfo->gpios);
788	pinfo->gpios = NULL;
789	return ret;
790}
791
792static int of_fsl_spi_free_chipselects(struct device *dev)
793{
794	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
795	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
796	int i;
797
798	if (!pinfo->gpios)
799		return 0;
800
801	for (i = 0; i < pdata->max_chipselect; i++) {
802		if (gpio_is_valid(pinfo->gpios[i]))
803			gpio_free(pinfo->gpios[i]);
804	}
805
806	kfree(pinfo->gpios);
807	kfree(pinfo->alow_flags);
808	return 0;
809}
810
811static int of_fsl_spi_probe(struct platform_device *ofdev)
812{
813	struct device *dev = &ofdev->dev;
814	struct device_node *np = ofdev->dev.of_node;
815	struct spi_master *master;
816	struct resource mem;
817	int irq = 0, type;
818	int ret = -ENOMEM;
 
 
 
 
 
819
820	ret = of_mpc8xxx_spi_probe(ofdev);
821	if (ret)
822		return ret;
823
824	type = fsl_spi_get_type(&ofdev->dev);
825	if (type == TYPE_FSL) {
826		ret = of_fsl_spi_get_chipselects(dev);
827		if (ret)
828			goto err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
829	}
830
831	ret = of_address_to_resource(np, 0, &mem);
832	if (ret)
833		goto err;
834
835	irq = irq_of_parse_and_map(np, 0);
836	if (!irq) {
837		ret = -EINVAL;
838		goto err;
839	}
840
841	master = fsl_spi_probe(dev, &mem, irq);
842	if (IS_ERR(master)) {
843		ret = PTR_ERR(master);
844		goto err;
845	}
846
847	return 0;
848
849err:
850	irq_dispose_mapping(irq);
851	if (type == TYPE_FSL)
852		of_fsl_spi_free_chipselects(dev);
 
853	return ret;
854}
855
856static int of_fsl_spi_remove(struct platform_device *ofdev)
857{
858	struct spi_master *master = platform_get_drvdata(ofdev);
859	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
860
861	fsl_spi_cpm_free(mpc8xxx_spi);
862	if (mpc8xxx_spi->type == TYPE_FSL)
863		of_fsl_spi_free_chipselects(&ofdev->dev);
864	return 0;
865}
866
867static struct platform_driver of_fsl_spi_driver = {
868	.driver = {
869		.name = "fsl_spi",
870		.of_match_table = of_fsl_spi_match,
871	},
872	.probe		= of_fsl_spi_probe,
873	.remove		= of_fsl_spi_remove,
874};
875
876#ifdef CONFIG_MPC832x_RDB
877/*
878 * XXX XXX XXX
879 * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
880 * only. The driver should go away soon, since newer MPC8323E-RDB's device
881 * tree can work with OpenFirmware driver. But for now we support old trees
882 * as well.
883 */
884static int plat_mpc8xxx_spi_probe(struct platform_device *pdev)
885{
886	struct resource *mem;
887	int irq;
888	struct spi_master *master;
889
890	if (!dev_get_platdata(&pdev->dev))
891		return -EINVAL;
892
893	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
894	if (!mem)
895		return -EINVAL;
896
897	irq = platform_get_irq(pdev, 0);
898	if (irq <= 0)
899		return -EINVAL;
900
901	master = fsl_spi_probe(&pdev->dev, mem, irq);
902	return PTR_ERR_OR_ZERO(master);
903}
904
905static int plat_mpc8xxx_spi_remove(struct platform_device *pdev)
906{
907	struct spi_master *master = platform_get_drvdata(pdev);
908	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
909
910	fsl_spi_cpm_free(mpc8xxx_spi);
911
912	return 0;
913}
914
915MODULE_ALIAS("platform:mpc8xxx_spi");
916static struct platform_driver mpc8xxx_spi_driver = {
917	.probe = plat_mpc8xxx_spi_probe,
918	.remove = plat_mpc8xxx_spi_remove,
919	.driver = {
920		.name = "mpc8xxx_spi",
921	},
922};
923
924static bool legacy_driver_failed;
925
926static void __init legacy_driver_register(void)
927{
928	legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
929}
930
931static void __exit legacy_driver_unregister(void)
932{
933	if (legacy_driver_failed)
934		return;
935	platform_driver_unregister(&mpc8xxx_spi_driver);
936}
937#else
938static void __init legacy_driver_register(void) {}
939static void __exit legacy_driver_unregister(void) {}
940#endif /* CONFIG_MPC832x_RDB */
941
942static int __init fsl_spi_init(void)
943{
944	legacy_driver_register();
945	return platform_driver_register(&of_fsl_spi_driver);
946}
947module_init(fsl_spi_init);
948
949static void __exit fsl_spi_exit(void)
950{
951	platform_driver_unregister(&of_fsl_spi_driver);
952	legacy_driver_unregister();
953}
954module_exit(fsl_spi_exit);
955
956MODULE_AUTHOR("Kumar Gala");
957MODULE_DESCRIPTION("Simple Freescale SPI Driver");
958MODULE_LICENSE("GPL");