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v4.6
  1/*
  2 * MPC52xx PSC in SPI mode driver.
  3 *
  4 * Maintainer: Dragos Carp
  5 *
  6 * Copyright (C) 2006 TOPTICA Photonics AG.
  7 *
  8 * This program is free software; you can redistribute  it and/or modify it
  9 * under  the terms of  the GNU General  Public License as published by the
 10 * Free Software Foundation;  either version 2 of the  License, or (at your
 11 * option) any later version.
 12 */
 13
 14#include <linux/module.h>
 15#include <linux/types.h>
 16#include <linux/errno.h>
 17#include <linux/interrupt.h>
 18#include <linux/of_address.h>
 19#include <linux/of_platform.h>
 20#include <linux/workqueue.h>
 21#include <linux/completion.h>
 22#include <linux/io.h>
 23#include <linux/delay.h>
 24#include <linux/spi/spi.h>
 25#include <linux/fsl_devices.h>
 26#include <linux/slab.h>
 27
 28#include <asm/mpc52xx.h>
 29#include <asm/mpc52xx_psc.h>
 30
 31#define MCLK 20000000 /* PSC port MClk in hz */
 32
 33struct mpc52xx_psc_spi {
 34	/* fsl_spi_platform data */
 35	void (*cs_control)(struct spi_device *spi, bool on);
 36	u32 sysclk;
 37
 38	/* driver internal data */
 39	struct mpc52xx_psc __iomem *psc;
 40	struct mpc52xx_psc_fifo __iomem *fifo;
 41	unsigned int irq;
 42	u8 bits_per_word;
 43	u8 busy;
 44
 45	struct workqueue_struct *workqueue;
 46	struct work_struct work;
 47
 48	struct list_head queue;
 49	spinlock_t lock;
 50
 51	struct completion done;
 52};
 53
 54/* controller state */
 55struct mpc52xx_psc_spi_cs {
 56	int bits_per_word;
 57	int speed_hz;
 58};
 59
 60/* set clock freq, clock ramp, bits per work
 61 * if t is NULL then reset the values to the default values
 62 */
 63static int mpc52xx_psc_spi_transfer_setup(struct spi_device *spi,
 64		struct spi_transfer *t)
 65{
 66	struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
 67
 68	cs->speed_hz = (t && t->speed_hz)
 69			? t->speed_hz : spi->max_speed_hz;
 70	cs->bits_per_word = (t && t->bits_per_word)
 71			? t->bits_per_word : spi->bits_per_word;
 72	cs->bits_per_word = ((cs->bits_per_word + 7) / 8) * 8;
 73	return 0;
 74}
 75
 76static void mpc52xx_psc_spi_activate_cs(struct spi_device *spi)
 77{
 78	struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
 79	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
 80	struct mpc52xx_psc __iomem *psc = mps->psc;
 81	u32 sicr;
 82	u16 ccr;
 83
 84	sicr = in_be32(&psc->sicr);
 85
 86	/* Set clock phase and polarity */
 87	if (spi->mode & SPI_CPHA)
 88		sicr |= 0x00001000;
 89	else
 90		sicr &= ~0x00001000;
 91	if (spi->mode & SPI_CPOL)
 92		sicr |= 0x00002000;
 93	else
 94		sicr &= ~0x00002000;
 95
 96	if (spi->mode & SPI_LSB_FIRST)
 97		sicr |= 0x10000000;
 98	else
 99		sicr &= ~0x10000000;
100	out_be32(&psc->sicr, sicr);
101
102	/* Set clock frequency and bits per word
103	 * Because psc->ccr is defined as 16bit register instead of 32bit
104	 * just set the lower byte of BitClkDiv
105	 */
106	ccr = in_be16((u16 __iomem *)&psc->ccr);
107	ccr &= 0xFF00;
108	if (cs->speed_hz)
109		ccr |= (MCLK / cs->speed_hz - 1) & 0xFF;
110	else /* by default SPI Clk 1MHz */
111		ccr |= (MCLK / 1000000 - 1) & 0xFF;
112	out_be16((u16 __iomem *)&psc->ccr, ccr);
113	mps->bits_per_word = cs->bits_per_word;
114
115	if (mps->cs_control)
116		mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 1 : 0);
117}
118
119static void mpc52xx_psc_spi_deactivate_cs(struct spi_device *spi)
120{
121	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
122
123	if (mps->cs_control)
124		mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 0 : 1);
125}
126
127#define MPC52xx_PSC_BUFSIZE (MPC52xx_PSC_RFNUM_MASK + 1)
128/* wake up when 80% fifo full */
129#define MPC52xx_PSC_RFALARM (MPC52xx_PSC_BUFSIZE * 20 / 100)
130
131static int mpc52xx_psc_spi_transfer_rxtx(struct spi_device *spi,
132						struct spi_transfer *t)
133{
134	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
135	struct mpc52xx_psc __iomem *psc = mps->psc;
136	struct mpc52xx_psc_fifo __iomem *fifo = mps->fifo;
137	unsigned rb = 0;	/* number of bytes receieved */
138	unsigned sb = 0;	/* number of bytes sent */
139	unsigned char *rx_buf = (unsigned char *)t->rx_buf;
140	unsigned char *tx_buf = (unsigned char *)t->tx_buf;
141	unsigned rfalarm;
142	unsigned send_at_once = MPC52xx_PSC_BUFSIZE;
143	unsigned recv_at_once;
144	int last_block = 0;
145
146	if (!t->tx_buf && !t->rx_buf && t->len)
147		return -EINVAL;
148
149	/* enable transmiter/receiver */
150	out_8(&psc->command, MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE);
151	while (rb < t->len) {
152		if (t->len - rb > MPC52xx_PSC_BUFSIZE) {
153			rfalarm = MPC52xx_PSC_RFALARM;
154			last_block = 0;
155		} else {
156			send_at_once = t->len - sb;
157			rfalarm = MPC52xx_PSC_BUFSIZE - (t->len - rb);
158			last_block = 1;
159		}
160
161		dev_dbg(&spi->dev, "send %d bytes...\n", send_at_once);
162		for (; send_at_once; sb++, send_at_once--) {
163			/* set EOF flag before the last word is sent */
164			if (send_at_once == 1 && last_block)
165				out_8(&psc->ircr2, 0x01);
166
167			if (tx_buf)
168				out_8(&psc->mpc52xx_psc_buffer_8, tx_buf[sb]);
169			else
170				out_8(&psc->mpc52xx_psc_buffer_8, 0);
171		}
172
173
174		/* enable interrupts and wait for wake up
175		 * if just one byte is expected the Rx FIFO genererates no
176		 * FFULL interrupt, so activate the RxRDY interrupt
177		 */
178		out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
179		if (t->len - rb == 1) {
180			out_8(&psc->mode, 0);
181		} else {
182			out_8(&psc->mode, MPC52xx_PSC_MODE_FFULL);
183			out_be16(&fifo->rfalarm, rfalarm);
184		}
185		out_be16(&psc->mpc52xx_psc_imr, MPC52xx_PSC_IMR_RXRDY);
186		wait_for_completion(&mps->done);
187		recv_at_once = in_be16(&fifo->rfnum);
188		dev_dbg(&spi->dev, "%d bytes received\n", recv_at_once);
189
190		send_at_once = recv_at_once;
191		if (rx_buf) {
192			for (; recv_at_once; rb++, recv_at_once--)
193				rx_buf[rb] = in_8(&psc->mpc52xx_psc_buffer_8);
194		} else {
195			for (; recv_at_once; rb++, recv_at_once--)
196				in_8(&psc->mpc52xx_psc_buffer_8);
197		}
198	}
199	/* disable transmiter/receiver */
200	out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
201
202	return 0;
203}
204
205static void mpc52xx_psc_spi_work(struct work_struct *work)
206{
207	struct mpc52xx_psc_spi *mps =
208		container_of(work, struct mpc52xx_psc_spi, work);
209
210	spin_lock_irq(&mps->lock);
211	mps->busy = 1;
212	while (!list_empty(&mps->queue)) {
213		struct spi_message *m;
214		struct spi_device *spi;
215		struct spi_transfer *t = NULL;
216		unsigned cs_change;
217		int status;
218
219		m = container_of(mps->queue.next, struct spi_message, queue);
220		list_del_init(&m->queue);
221		spin_unlock_irq(&mps->lock);
222
223		spi = m->spi;
224		cs_change = 1;
225		status = 0;
226		list_for_each_entry (t, &m->transfers, transfer_list) {
227			if (t->bits_per_word || t->speed_hz) {
228				status = mpc52xx_psc_spi_transfer_setup(spi, t);
229				if (status < 0)
230					break;
231			}
232
233			if (cs_change)
234				mpc52xx_psc_spi_activate_cs(spi);
235			cs_change = t->cs_change;
236
237			status = mpc52xx_psc_spi_transfer_rxtx(spi, t);
238			if (status)
239				break;
240			m->actual_length += t->len;
241
242			if (t->delay_usecs)
243				udelay(t->delay_usecs);
244
245			if (cs_change)
246				mpc52xx_psc_spi_deactivate_cs(spi);
247		}
248
249		m->status = status;
250		if (m->complete)
251			m->complete(m->context);
252
253		if (status || !cs_change)
254			mpc52xx_psc_spi_deactivate_cs(spi);
255
256		mpc52xx_psc_spi_transfer_setup(spi, NULL);
257
258		spin_lock_irq(&mps->lock);
259	}
260	mps->busy = 0;
261	spin_unlock_irq(&mps->lock);
262}
263
264static int mpc52xx_psc_spi_setup(struct spi_device *spi)
265{
266	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
267	struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
268	unsigned long flags;
269
270	if (spi->bits_per_word%8)
271		return -EINVAL;
272
273	if (!cs) {
274		cs = kzalloc(sizeof *cs, GFP_KERNEL);
275		if (!cs)
276			return -ENOMEM;
277		spi->controller_state = cs;
278	}
279
280	cs->bits_per_word = spi->bits_per_word;
281	cs->speed_hz = spi->max_speed_hz;
282
283	spin_lock_irqsave(&mps->lock, flags);
284	if (!mps->busy)
285		mpc52xx_psc_spi_deactivate_cs(spi);
286	spin_unlock_irqrestore(&mps->lock, flags);
287
288	return 0;
289}
290
291static int mpc52xx_psc_spi_transfer(struct spi_device *spi,
292		struct spi_message *m)
293{
294	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
295	unsigned long flags;
296
297	m->actual_length = 0;
298	m->status = -EINPROGRESS;
299
300	spin_lock_irqsave(&mps->lock, flags);
301	list_add_tail(&m->queue, &mps->queue);
302	queue_work(mps->workqueue, &mps->work);
303	spin_unlock_irqrestore(&mps->lock, flags);
304
305	return 0;
306}
307
308static void mpc52xx_psc_spi_cleanup(struct spi_device *spi)
309{
310	kfree(spi->controller_state);
311}
312
313static int mpc52xx_psc_spi_port_config(int psc_id, struct mpc52xx_psc_spi *mps)
314{
315	struct mpc52xx_psc __iomem *psc = mps->psc;
316	struct mpc52xx_psc_fifo __iomem *fifo = mps->fifo;
317	u32 mclken_div;
318	int ret;
319
320	/* default sysclk is 512MHz */
321	mclken_div = (mps->sysclk ? mps->sysclk : 512000000) / MCLK;
322	ret = mpc52xx_set_psc_clkdiv(psc_id, mclken_div);
323	if (ret)
324		return ret;
325
326	/* Reset the PSC into a known state */
327	out_8(&psc->command, MPC52xx_PSC_RST_RX);
328	out_8(&psc->command, MPC52xx_PSC_RST_TX);
329	out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
330
331	/* Disable interrupts, interrupts are based on alarm level */
332	out_be16(&psc->mpc52xx_psc_imr, 0);
333	out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
334	out_8(&fifo->rfcntl, 0);
335	out_8(&psc->mode, MPC52xx_PSC_MODE_FFULL);
336
337	/* Configure 8bit codec mode as a SPI master and use EOF flags */
338	/* SICR_SIM_CODEC8|SICR_GENCLK|SICR_SPI|SICR_MSTR|SICR_USEEOF */
339	out_be32(&psc->sicr, 0x0180C800);
340	out_be16((u16 __iomem *)&psc->ccr, 0x070F); /* default SPI Clk 1MHz */
341
342	/* Set 2ms DTL delay */
343	out_8(&psc->ctur, 0x00);
344	out_8(&psc->ctlr, 0x84);
345
346	mps->bits_per_word = 8;
347
348	return 0;
349}
350
351static irqreturn_t mpc52xx_psc_spi_isr(int irq, void *dev_id)
352{
353	struct mpc52xx_psc_spi *mps = (struct mpc52xx_psc_spi *)dev_id;
354	struct mpc52xx_psc __iomem *psc = mps->psc;
355
356	/* disable interrupt and wake up the work queue */
357	if (in_be16(&psc->mpc52xx_psc_isr) & MPC52xx_PSC_IMR_RXRDY) {
358		out_be16(&psc->mpc52xx_psc_imr, 0);
359		complete(&mps->done);
360		return IRQ_HANDLED;
361	}
362	return IRQ_NONE;
363}
364
365/* bus_num is used only for the case dev->platform_data == NULL */
366static int mpc52xx_psc_spi_do_probe(struct device *dev, u32 regaddr,
367				u32 size, unsigned int irq, s16 bus_num)
368{
369	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
370	struct mpc52xx_psc_spi *mps;
371	struct spi_master *master;
372	int ret;
373
374	master = spi_alloc_master(dev, sizeof *mps);
375	if (master == NULL)
376		return -ENOMEM;
377
378	dev_set_drvdata(dev, master);
379	mps = spi_master_get_devdata(master);
380
381	/* the spi->mode bits understood by this driver: */
382	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
383
384	mps->irq = irq;
385	if (pdata == NULL) {
386		dev_warn(dev,
387			 "probe called without platform data, no cs_control function will be called\n");
388		mps->cs_control = NULL;
389		mps->sysclk = 0;
390		master->bus_num = bus_num;
391		master->num_chipselect = 255;
392	} else {
393		mps->cs_control = pdata->cs_control;
394		mps->sysclk = pdata->sysclk;
395		master->bus_num = pdata->bus_num;
396		master->num_chipselect = pdata->max_chipselect;
397	}
398	master->setup = mpc52xx_psc_spi_setup;
399	master->transfer = mpc52xx_psc_spi_transfer;
400	master->cleanup = mpc52xx_psc_spi_cleanup;
401	master->dev.of_node = dev->of_node;
402
403	mps->psc = ioremap(regaddr, size);
404	if (!mps->psc) {
405		dev_err(dev, "could not ioremap I/O port range\n");
406		ret = -EFAULT;
407		goto free_master;
408	}
409	/* On the 5200, fifo regs are immediately ajacent to the psc regs */
410	mps->fifo = ((void __iomem *)mps->psc) + sizeof(struct mpc52xx_psc);
411
412	ret = request_irq(mps->irq, mpc52xx_psc_spi_isr, 0, "mpc52xx-psc-spi",
413				mps);
414	if (ret)
415		goto free_master;
416
417	ret = mpc52xx_psc_spi_port_config(master->bus_num, mps);
418	if (ret < 0) {
419		dev_err(dev, "can't configure PSC! Is it capable of SPI?\n");
420		goto free_irq;
421	}
422
423	spin_lock_init(&mps->lock);
424	init_completion(&mps->done);
425	INIT_WORK(&mps->work, mpc52xx_psc_spi_work);
426	INIT_LIST_HEAD(&mps->queue);
427
428	mps->workqueue = create_singlethread_workqueue(
429		dev_name(master->dev.parent));
430	if (mps->workqueue == NULL) {
431		ret = -EBUSY;
432		goto free_irq;
433	}
434
435	ret = spi_register_master(master);
436	if (ret < 0)
437		goto unreg_master;
438
439	return ret;
440
441unreg_master:
442	destroy_workqueue(mps->workqueue);
443free_irq:
444	free_irq(mps->irq, mps);
445free_master:
446	if (mps->psc)
447		iounmap(mps->psc);
448	spi_master_put(master);
449
450	return ret;
451}
452
453static int mpc52xx_psc_spi_of_probe(struct platform_device *op)
454{
455	const u32 *regaddr_p;
456	u64 regaddr64, size64;
457	s16 id = -1;
458
459	regaddr_p = of_get_address(op->dev.of_node, 0, &size64, NULL);
460	if (!regaddr_p) {
461		dev_err(&op->dev, "Invalid PSC address\n");
462		return -EINVAL;
463	}
464	regaddr64 = of_translate_address(op->dev.of_node, regaddr_p);
465
466	/* get PSC id (1..6, used by port_config) */
467	if (op->dev.platform_data == NULL) {
468		const u32 *psc_nump;
469
470		psc_nump = of_get_property(op->dev.of_node, "cell-index", NULL);
471		if (!psc_nump || *psc_nump > 5) {
472			dev_err(&op->dev, "Invalid cell-index property\n");
473			return -EINVAL;
474		}
475		id = *psc_nump + 1;
476	}
477
478	return mpc52xx_psc_spi_do_probe(&op->dev, (u32)regaddr64, (u32)size64,
479				irq_of_parse_and_map(op->dev.of_node, 0), id);
480}
481
482static int mpc52xx_psc_spi_of_remove(struct platform_device *op)
483{
484	struct spi_master *master = spi_master_get(platform_get_drvdata(op));
485	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(master);
486
487	flush_workqueue(mps->workqueue);
488	destroy_workqueue(mps->workqueue);
489	spi_unregister_master(master);
490	free_irq(mps->irq, mps);
491	if (mps->psc)
492		iounmap(mps->psc);
493	spi_master_put(master);
494
495	return 0;
496}
497
498static const struct of_device_id mpc52xx_psc_spi_of_match[] = {
499	{ .compatible = "fsl,mpc5200-psc-spi", },
500	{ .compatible = "mpc5200-psc-spi", }, /* old */
501	{}
502};
503
504MODULE_DEVICE_TABLE(of, mpc52xx_psc_spi_of_match);
505
506static struct platform_driver mpc52xx_psc_spi_of_driver = {
507	.probe = mpc52xx_psc_spi_of_probe,
508	.remove = mpc52xx_psc_spi_of_remove,
509	.driver = {
510		.name = "mpc52xx-psc-spi",
511		.of_match_table = mpc52xx_psc_spi_of_match,
512	},
513};
514module_platform_driver(mpc52xx_psc_spi_of_driver);
515
516MODULE_AUTHOR("Dragos Carp");
517MODULE_DESCRIPTION("MPC52xx PSC SPI Driver");
518MODULE_LICENSE("GPL");
v4.17
  1/*
  2 * MPC52xx PSC in SPI mode driver.
  3 *
  4 * Maintainer: Dragos Carp
  5 *
  6 * Copyright (C) 2006 TOPTICA Photonics AG.
  7 *
  8 * This program is free software; you can redistribute  it and/or modify it
  9 * under  the terms of  the GNU General  Public License as published by the
 10 * Free Software Foundation;  either version 2 of the  License, or (at your
 11 * option) any later version.
 12 */
 13
 14#include <linux/module.h>
 15#include <linux/types.h>
 16#include <linux/errno.h>
 17#include <linux/interrupt.h>
 18#include <linux/of_address.h>
 19#include <linux/of_platform.h>
 20#include <linux/workqueue.h>
 21#include <linux/completion.h>
 22#include <linux/io.h>
 23#include <linux/delay.h>
 24#include <linux/spi/spi.h>
 25#include <linux/fsl_devices.h>
 26#include <linux/slab.h>
 27
 28#include <asm/mpc52xx.h>
 29#include <asm/mpc52xx_psc.h>
 30
 31#define MCLK 20000000 /* PSC port MClk in hz */
 32
 33struct mpc52xx_psc_spi {
 34	/* fsl_spi_platform data */
 35	void (*cs_control)(struct spi_device *spi, bool on);
 36	u32 sysclk;
 37
 38	/* driver internal data */
 39	struct mpc52xx_psc __iomem *psc;
 40	struct mpc52xx_psc_fifo __iomem *fifo;
 41	unsigned int irq;
 42	u8 bits_per_word;
 43	u8 busy;
 44
 
 45	struct work_struct work;
 46
 47	struct list_head queue;
 48	spinlock_t lock;
 49
 50	struct completion done;
 51};
 52
 53/* controller state */
 54struct mpc52xx_psc_spi_cs {
 55	int bits_per_word;
 56	int speed_hz;
 57};
 58
 59/* set clock freq, clock ramp, bits per work
 60 * if t is NULL then reset the values to the default values
 61 */
 62static int mpc52xx_psc_spi_transfer_setup(struct spi_device *spi,
 63		struct spi_transfer *t)
 64{
 65	struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
 66
 67	cs->speed_hz = (t && t->speed_hz)
 68			? t->speed_hz : spi->max_speed_hz;
 69	cs->bits_per_word = (t && t->bits_per_word)
 70			? t->bits_per_word : spi->bits_per_word;
 71	cs->bits_per_word = ((cs->bits_per_word + 7) / 8) * 8;
 72	return 0;
 73}
 74
 75static void mpc52xx_psc_spi_activate_cs(struct spi_device *spi)
 76{
 77	struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
 78	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
 79	struct mpc52xx_psc __iomem *psc = mps->psc;
 80	u32 sicr;
 81	u16 ccr;
 82
 83	sicr = in_be32(&psc->sicr);
 84
 85	/* Set clock phase and polarity */
 86	if (spi->mode & SPI_CPHA)
 87		sicr |= 0x00001000;
 88	else
 89		sicr &= ~0x00001000;
 90	if (spi->mode & SPI_CPOL)
 91		sicr |= 0x00002000;
 92	else
 93		sicr &= ~0x00002000;
 94
 95	if (spi->mode & SPI_LSB_FIRST)
 96		sicr |= 0x10000000;
 97	else
 98		sicr &= ~0x10000000;
 99	out_be32(&psc->sicr, sicr);
100
101	/* Set clock frequency and bits per word
102	 * Because psc->ccr is defined as 16bit register instead of 32bit
103	 * just set the lower byte of BitClkDiv
104	 */
105	ccr = in_be16((u16 __iomem *)&psc->ccr);
106	ccr &= 0xFF00;
107	if (cs->speed_hz)
108		ccr |= (MCLK / cs->speed_hz - 1) & 0xFF;
109	else /* by default SPI Clk 1MHz */
110		ccr |= (MCLK / 1000000 - 1) & 0xFF;
111	out_be16((u16 __iomem *)&psc->ccr, ccr);
112	mps->bits_per_word = cs->bits_per_word;
113
114	if (mps->cs_control)
115		mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 1 : 0);
116}
117
118static void mpc52xx_psc_spi_deactivate_cs(struct spi_device *spi)
119{
120	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
121
122	if (mps->cs_control)
123		mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 0 : 1);
124}
125
126#define MPC52xx_PSC_BUFSIZE (MPC52xx_PSC_RFNUM_MASK + 1)
127/* wake up when 80% fifo full */
128#define MPC52xx_PSC_RFALARM (MPC52xx_PSC_BUFSIZE * 20 / 100)
129
130static int mpc52xx_psc_spi_transfer_rxtx(struct spi_device *spi,
131						struct spi_transfer *t)
132{
133	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
134	struct mpc52xx_psc __iomem *psc = mps->psc;
135	struct mpc52xx_psc_fifo __iomem *fifo = mps->fifo;
136	unsigned rb = 0;	/* number of bytes receieved */
137	unsigned sb = 0;	/* number of bytes sent */
138	unsigned char *rx_buf = (unsigned char *)t->rx_buf;
139	unsigned char *tx_buf = (unsigned char *)t->tx_buf;
140	unsigned rfalarm;
141	unsigned send_at_once = MPC52xx_PSC_BUFSIZE;
142	unsigned recv_at_once;
143	int last_block = 0;
144
145	if (!t->tx_buf && !t->rx_buf && t->len)
146		return -EINVAL;
147
148	/* enable transmiter/receiver */
149	out_8(&psc->command, MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE);
150	while (rb < t->len) {
151		if (t->len - rb > MPC52xx_PSC_BUFSIZE) {
152			rfalarm = MPC52xx_PSC_RFALARM;
153			last_block = 0;
154		} else {
155			send_at_once = t->len - sb;
156			rfalarm = MPC52xx_PSC_BUFSIZE - (t->len - rb);
157			last_block = 1;
158		}
159
160		dev_dbg(&spi->dev, "send %d bytes...\n", send_at_once);
161		for (; send_at_once; sb++, send_at_once--) {
162			/* set EOF flag before the last word is sent */
163			if (send_at_once == 1 && last_block)
164				out_8(&psc->ircr2, 0x01);
165
166			if (tx_buf)
167				out_8(&psc->mpc52xx_psc_buffer_8, tx_buf[sb]);
168			else
169				out_8(&psc->mpc52xx_psc_buffer_8, 0);
170		}
171
172
173		/* enable interrupts and wait for wake up
174		 * if just one byte is expected the Rx FIFO genererates no
175		 * FFULL interrupt, so activate the RxRDY interrupt
176		 */
177		out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
178		if (t->len - rb == 1) {
179			out_8(&psc->mode, 0);
180		} else {
181			out_8(&psc->mode, MPC52xx_PSC_MODE_FFULL);
182			out_be16(&fifo->rfalarm, rfalarm);
183		}
184		out_be16(&psc->mpc52xx_psc_imr, MPC52xx_PSC_IMR_RXRDY);
185		wait_for_completion(&mps->done);
186		recv_at_once = in_be16(&fifo->rfnum);
187		dev_dbg(&spi->dev, "%d bytes received\n", recv_at_once);
188
189		send_at_once = recv_at_once;
190		if (rx_buf) {
191			for (; recv_at_once; rb++, recv_at_once--)
192				rx_buf[rb] = in_8(&psc->mpc52xx_psc_buffer_8);
193		} else {
194			for (; recv_at_once; rb++, recv_at_once--)
195				in_8(&psc->mpc52xx_psc_buffer_8);
196		}
197	}
198	/* disable transmiter/receiver */
199	out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
200
201	return 0;
202}
203
204static void mpc52xx_psc_spi_work(struct work_struct *work)
205{
206	struct mpc52xx_psc_spi *mps =
207		container_of(work, struct mpc52xx_psc_spi, work);
208
209	spin_lock_irq(&mps->lock);
210	mps->busy = 1;
211	while (!list_empty(&mps->queue)) {
212		struct spi_message *m;
213		struct spi_device *spi;
214		struct spi_transfer *t = NULL;
215		unsigned cs_change;
216		int status;
217
218		m = container_of(mps->queue.next, struct spi_message, queue);
219		list_del_init(&m->queue);
220		spin_unlock_irq(&mps->lock);
221
222		spi = m->spi;
223		cs_change = 1;
224		status = 0;
225		list_for_each_entry (t, &m->transfers, transfer_list) {
226			if (t->bits_per_word || t->speed_hz) {
227				status = mpc52xx_psc_spi_transfer_setup(spi, t);
228				if (status < 0)
229					break;
230			}
231
232			if (cs_change)
233				mpc52xx_psc_spi_activate_cs(spi);
234			cs_change = t->cs_change;
235
236			status = mpc52xx_psc_spi_transfer_rxtx(spi, t);
237			if (status)
238				break;
239			m->actual_length += t->len;
240
241			if (t->delay_usecs)
242				udelay(t->delay_usecs);
243
244			if (cs_change)
245				mpc52xx_psc_spi_deactivate_cs(spi);
246		}
247
248		m->status = status;
249		if (m->complete)
250			m->complete(m->context);
251
252		if (status || !cs_change)
253			mpc52xx_psc_spi_deactivate_cs(spi);
254
255		mpc52xx_psc_spi_transfer_setup(spi, NULL);
256
257		spin_lock_irq(&mps->lock);
258	}
259	mps->busy = 0;
260	spin_unlock_irq(&mps->lock);
261}
262
263static int mpc52xx_psc_spi_setup(struct spi_device *spi)
264{
265	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
266	struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
267	unsigned long flags;
268
269	if (spi->bits_per_word%8)
270		return -EINVAL;
271
272	if (!cs) {
273		cs = kzalloc(sizeof *cs, GFP_KERNEL);
274		if (!cs)
275			return -ENOMEM;
276		spi->controller_state = cs;
277	}
278
279	cs->bits_per_word = spi->bits_per_word;
280	cs->speed_hz = spi->max_speed_hz;
281
282	spin_lock_irqsave(&mps->lock, flags);
283	if (!mps->busy)
284		mpc52xx_psc_spi_deactivate_cs(spi);
285	spin_unlock_irqrestore(&mps->lock, flags);
286
287	return 0;
288}
289
290static int mpc52xx_psc_spi_transfer(struct spi_device *spi,
291		struct spi_message *m)
292{
293	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
294	unsigned long flags;
295
296	m->actual_length = 0;
297	m->status = -EINPROGRESS;
298
299	spin_lock_irqsave(&mps->lock, flags);
300	list_add_tail(&m->queue, &mps->queue);
301	schedule_work(&mps->work);
302	spin_unlock_irqrestore(&mps->lock, flags);
303
304	return 0;
305}
306
307static void mpc52xx_psc_spi_cleanup(struct spi_device *spi)
308{
309	kfree(spi->controller_state);
310}
311
312static int mpc52xx_psc_spi_port_config(int psc_id, struct mpc52xx_psc_spi *mps)
313{
314	struct mpc52xx_psc __iomem *psc = mps->psc;
315	struct mpc52xx_psc_fifo __iomem *fifo = mps->fifo;
316	u32 mclken_div;
317	int ret;
318
319	/* default sysclk is 512MHz */
320	mclken_div = (mps->sysclk ? mps->sysclk : 512000000) / MCLK;
321	ret = mpc52xx_set_psc_clkdiv(psc_id, mclken_div);
322	if (ret)
323		return ret;
324
325	/* Reset the PSC into a known state */
326	out_8(&psc->command, MPC52xx_PSC_RST_RX);
327	out_8(&psc->command, MPC52xx_PSC_RST_TX);
328	out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
329
330	/* Disable interrupts, interrupts are based on alarm level */
331	out_be16(&psc->mpc52xx_psc_imr, 0);
332	out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
333	out_8(&fifo->rfcntl, 0);
334	out_8(&psc->mode, MPC52xx_PSC_MODE_FFULL);
335
336	/* Configure 8bit codec mode as a SPI master and use EOF flags */
337	/* SICR_SIM_CODEC8|SICR_GENCLK|SICR_SPI|SICR_MSTR|SICR_USEEOF */
338	out_be32(&psc->sicr, 0x0180C800);
339	out_be16((u16 __iomem *)&psc->ccr, 0x070F); /* default SPI Clk 1MHz */
340
341	/* Set 2ms DTL delay */
342	out_8(&psc->ctur, 0x00);
343	out_8(&psc->ctlr, 0x84);
344
345	mps->bits_per_word = 8;
346
347	return 0;
348}
349
350static irqreturn_t mpc52xx_psc_spi_isr(int irq, void *dev_id)
351{
352	struct mpc52xx_psc_spi *mps = (struct mpc52xx_psc_spi *)dev_id;
353	struct mpc52xx_psc __iomem *psc = mps->psc;
354
355	/* disable interrupt and wake up the work queue */
356	if (in_be16(&psc->mpc52xx_psc_isr) & MPC52xx_PSC_IMR_RXRDY) {
357		out_be16(&psc->mpc52xx_psc_imr, 0);
358		complete(&mps->done);
359		return IRQ_HANDLED;
360	}
361	return IRQ_NONE;
362}
363
364/* bus_num is used only for the case dev->platform_data == NULL */
365static int mpc52xx_psc_spi_do_probe(struct device *dev, u32 regaddr,
366				u32 size, unsigned int irq, s16 bus_num)
367{
368	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
369	struct mpc52xx_psc_spi *mps;
370	struct spi_master *master;
371	int ret;
372
373	master = spi_alloc_master(dev, sizeof *mps);
374	if (master == NULL)
375		return -ENOMEM;
376
377	dev_set_drvdata(dev, master);
378	mps = spi_master_get_devdata(master);
379
380	/* the spi->mode bits understood by this driver: */
381	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
382
383	mps->irq = irq;
384	if (pdata == NULL) {
385		dev_warn(dev,
386			 "probe called without platform data, no cs_control function will be called\n");
387		mps->cs_control = NULL;
388		mps->sysclk = 0;
389		master->bus_num = bus_num;
390		master->num_chipselect = 255;
391	} else {
392		mps->cs_control = pdata->cs_control;
393		mps->sysclk = pdata->sysclk;
394		master->bus_num = pdata->bus_num;
395		master->num_chipselect = pdata->max_chipselect;
396	}
397	master->setup = mpc52xx_psc_spi_setup;
398	master->transfer = mpc52xx_psc_spi_transfer;
399	master->cleanup = mpc52xx_psc_spi_cleanup;
400	master->dev.of_node = dev->of_node;
401
402	mps->psc = ioremap(regaddr, size);
403	if (!mps->psc) {
404		dev_err(dev, "could not ioremap I/O port range\n");
405		ret = -EFAULT;
406		goto free_master;
407	}
408	/* On the 5200, fifo regs are immediately ajacent to the psc regs */
409	mps->fifo = ((void __iomem *)mps->psc) + sizeof(struct mpc52xx_psc);
410
411	ret = request_irq(mps->irq, mpc52xx_psc_spi_isr, 0, "mpc52xx-psc-spi",
412				mps);
413	if (ret)
414		goto free_master;
415
416	ret = mpc52xx_psc_spi_port_config(master->bus_num, mps);
417	if (ret < 0) {
418		dev_err(dev, "can't configure PSC! Is it capable of SPI?\n");
419		goto free_irq;
420	}
421
422	spin_lock_init(&mps->lock);
423	init_completion(&mps->done);
424	INIT_WORK(&mps->work, mpc52xx_psc_spi_work);
425	INIT_LIST_HEAD(&mps->queue);
426
 
 
 
 
 
 
 
427	ret = spi_register_master(master);
428	if (ret < 0)
429		goto free_irq;
430
431	return ret;
432
 
 
433free_irq:
434	free_irq(mps->irq, mps);
435free_master:
436	if (mps->psc)
437		iounmap(mps->psc);
438	spi_master_put(master);
439
440	return ret;
441}
442
443static int mpc52xx_psc_spi_of_probe(struct platform_device *op)
444{
445	const u32 *regaddr_p;
446	u64 regaddr64, size64;
447	s16 id = -1;
448
449	regaddr_p = of_get_address(op->dev.of_node, 0, &size64, NULL);
450	if (!regaddr_p) {
451		dev_err(&op->dev, "Invalid PSC address\n");
452		return -EINVAL;
453	}
454	regaddr64 = of_translate_address(op->dev.of_node, regaddr_p);
455
456	/* get PSC id (1..6, used by port_config) */
457	if (op->dev.platform_data == NULL) {
458		const u32 *psc_nump;
459
460		psc_nump = of_get_property(op->dev.of_node, "cell-index", NULL);
461		if (!psc_nump || *psc_nump > 5) {
462			dev_err(&op->dev, "Invalid cell-index property\n");
463			return -EINVAL;
464		}
465		id = *psc_nump + 1;
466	}
467
468	return mpc52xx_psc_spi_do_probe(&op->dev, (u32)regaddr64, (u32)size64,
469				irq_of_parse_and_map(op->dev.of_node, 0), id);
470}
471
472static int mpc52xx_psc_spi_of_remove(struct platform_device *op)
473{
474	struct spi_master *master = spi_master_get(platform_get_drvdata(op));
475	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(master);
476
477	flush_work(&mps->work);
 
478	spi_unregister_master(master);
479	free_irq(mps->irq, mps);
480	if (mps->psc)
481		iounmap(mps->psc);
482	spi_master_put(master);
483
484	return 0;
485}
486
487static const struct of_device_id mpc52xx_psc_spi_of_match[] = {
488	{ .compatible = "fsl,mpc5200-psc-spi", },
489	{ .compatible = "mpc5200-psc-spi", }, /* old */
490	{}
491};
492
493MODULE_DEVICE_TABLE(of, mpc52xx_psc_spi_of_match);
494
495static struct platform_driver mpc52xx_psc_spi_of_driver = {
496	.probe = mpc52xx_psc_spi_of_probe,
497	.remove = mpc52xx_psc_spi_of_remove,
498	.driver = {
499		.name = "mpc52xx-psc-spi",
500		.of_match_table = mpc52xx_psc_spi_of_match,
501	},
502};
503module_platform_driver(mpc52xx_psc_spi_of_driver);
504
505MODULE_AUTHOR("Dragos Carp");
506MODULE_DESCRIPTION("MPC52xx PSC SPI Driver");
507MODULE_LICENSE("GPL");