Linux Audio

Check our new training course

Loading...
v5.9
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * MPC52xx PSC in SPI mode driver.
  4 *
  5 * Maintainer: Dragos Carp
  6 *
  7 * Copyright (C) 2006 TOPTICA Photonics AG.
 
 
 
 
 
  8 */
  9
 10#include <linux/module.h>
 
 11#include <linux/types.h>
 12#include <linux/errno.h>
 13#include <linux/interrupt.h>
 14#include <linux/of_address.h>
 15#include <linux/of_platform.h>
 16#include <linux/workqueue.h>
 17#include <linux/completion.h>
 18#include <linux/io.h>
 19#include <linux/delay.h>
 20#include <linux/spi/spi.h>
 21#include <linux/fsl_devices.h>
 22#include <linux/slab.h>
 23
 24#include <asm/mpc52xx.h>
 25#include <asm/mpc52xx_psc.h>
 26
 27#define MCLK 20000000 /* PSC port MClk in hz */
 28
 29struct mpc52xx_psc_spi {
 30	/* fsl_spi_platform data */
 31	void (*cs_control)(struct spi_device *spi, bool on);
 32	u32 sysclk;
 33
 34	/* driver internal data */
 35	struct mpc52xx_psc __iomem *psc;
 36	struct mpc52xx_psc_fifo __iomem *fifo;
 37	unsigned int irq;
 38	u8 bits_per_word;
 39	u8 busy;
 40
 
 41	struct work_struct work;
 42
 43	struct list_head queue;
 44	spinlock_t lock;
 45
 46	struct completion done;
 47};
 48
 49/* controller state */
 50struct mpc52xx_psc_spi_cs {
 51	int bits_per_word;
 52	int speed_hz;
 53};
 54
 55/* set clock freq, clock ramp, bits per work
 56 * if t is NULL then reset the values to the default values
 57 */
 58static int mpc52xx_psc_spi_transfer_setup(struct spi_device *spi,
 59		struct spi_transfer *t)
 60{
 61	struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
 62
 63	cs->speed_hz = (t && t->speed_hz)
 64			? t->speed_hz : spi->max_speed_hz;
 65	cs->bits_per_word = (t && t->bits_per_word)
 66			? t->bits_per_word : spi->bits_per_word;
 67	cs->bits_per_word = ((cs->bits_per_word + 7) / 8) * 8;
 68	return 0;
 69}
 70
 71static void mpc52xx_psc_spi_activate_cs(struct spi_device *spi)
 72{
 73	struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
 74	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
 75	struct mpc52xx_psc __iomem *psc = mps->psc;
 76	u32 sicr;
 77	u16 ccr;
 78
 79	sicr = in_be32(&psc->sicr);
 80
 81	/* Set clock phase and polarity */
 82	if (spi->mode & SPI_CPHA)
 83		sicr |= 0x00001000;
 84	else
 85		sicr &= ~0x00001000;
 86	if (spi->mode & SPI_CPOL)
 87		sicr |= 0x00002000;
 88	else
 89		sicr &= ~0x00002000;
 90
 91	if (spi->mode & SPI_LSB_FIRST)
 92		sicr |= 0x10000000;
 93	else
 94		sicr &= ~0x10000000;
 95	out_be32(&psc->sicr, sicr);
 96
 97	/* Set clock frequency and bits per word
 98	 * Because psc->ccr is defined as 16bit register instead of 32bit
 99	 * just set the lower byte of BitClkDiv
100	 */
101	ccr = in_be16((u16 __iomem *)&psc->ccr);
102	ccr &= 0xFF00;
103	if (cs->speed_hz)
104		ccr |= (MCLK / cs->speed_hz - 1) & 0xFF;
105	else /* by default SPI Clk 1MHz */
106		ccr |= (MCLK / 1000000 - 1) & 0xFF;
107	out_be16((u16 __iomem *)&psc->ccr, ccr);
108	mps->bits_per_word = cs->bits_per_word;
109
110	if (mps->cs_control)
111		mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 1 : 0);
112}
113
114static void mpc52xx_psc_spi_deactivate_cs(struct spi_device *spi)
115{
116	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
117
118	if (mps->cs_control)
119		mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 0 : 1);
120}
121
122#define MPC52xx_PSC_BUFSIZE (MPC52xx_PSC_RFNUM_MASK + 1)
123/* wake up when 80% fifo full */
124#define MPC52xx_PSC_RFALARM (MPC52xx_PSC_BUFSIZE * 20 / 100)
125
126static int mpc52xx_psc_spi_transfer_rxtx(struct spi_device *spi,
127						struct spi_transfer *t)
128{
129	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
130	struct mpc52xx_psc __iomem *psc = mps->psc;
131	struct mpc52xx_psc_fifo __iomem *fifo = mps->fifo;
132	unsigned rb = 0;	/* number of bytes receieved */
133	unsigned sb = 0;	/* number of bytes sent */
134	unsigned char *rx_buf = (unsigned char *)t->rx_buf;
135	unsigned char *tx_buf = (unsigned char *)t->tx_buf;
136	unsigned rfalarm;
137	unsigned send_at_once = MPC52xx_PSC_BUFSIZE;
138	unsigned recv_at_once;
139	int last_block = 0;
140
141	if (!t->tx_buf && !t->rx_buf && t->len)
142		return -EINVAL;
143
144	/* enable transmiter/receiver */
145	out_8(&psc->command, MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE);
146	while (rb < t->len) {
147		if (t->len - rb > MPC52xx_PSC_BUFSIZE) {
148			rfalarm = MPC52xx_PSC_RFALARM;
149			last_block = 0;
150		} else {
151			send_at_once = t->len - sb;
152			rfalarm = MPC52xx_PSC_BUFSIZE - (t->len - rb);
153			last_block = 1;
154		}
155
156		dev_dbg(&spi->dev, "send %d bytes...\n", send_at_once);
157		for (; send_at_once; sb++, send_at_once--) {
158			/* set EOF flag before the last word is sent */
159			if (send_at_once == 1 && last_block)
160				out_8(&psc->ircr2, 0x01);
161
162			if (tx_buf)
163				out_8(&psc->mpc52xx_psc_buffer_8, tx_buf[sb]);
164			else
165				out_8(&psc->mpc52xx_psc_buffer_8, 0);
166		}
167
168
169		/* enable interrupts and wait for wake up
170		 * if just one byte is expected the Rx FIFO genererates no
171		 * FFULL interrupt, so activate the RxRDY interrupt
172		 */
173		out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
174		if (t->len - rb == 1) {
175			out_8(&psc->mode, 0);
176		} else {
177			out_8(&psc->mode, MPC52xx_PSC_MODE_FFULL);
178			out_be16(&fifo->rfalarm, rfalarm);
179		}
180		out_be16(&psc->mpc52xx_psc_imr, MPC52xx_PSC_IMR_RXRDY);
181		wait_for_completion(&mps->done);
182		recv_at_once = in_be16(&fifo->rfnum);
183		dev_dbg(&spi->dev, "%d bytes received\n", recv_at_once);
184
185		send_at_once = recv_at_once;
186		if (rx_buf) {
187			for (; recv_at_once; rb++, recv_at_once--)
188				rx_buf[rb] = in_8(&psc->mpc52xx_psc_buffer_8);
189		} else {
190			for (; recv_at_once; rb++, recv_at_once--)
191				in_8(&psc->mpc52xx_psc_buffer_8);
192		}
193	}
194	/* disable transmiter/receiver */
195	out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
196
197	return 0;
198}
199
200static void mpc52xx_psc_spi_work(struct work_struct *work)
201{
202	struct mpc52xx_psc_spi *mps =
203		container_of(work, struct mpc52xx_psc_spi, work);
204
205	spin_lock_irq(&mps->lock);
206	mps->busy = 1;
207	while (!list_empty(&mps->queue)) {
208		struct spi_message *m;
209		struct spi_device *spi;
210		struct spi_transfer *t = NULL;
211		unsigned cs_change;
212		int status;
213
214		m = container_of(mps->queue.next, struct spi_message, queue);
215		list_del_init(&m->queue);
216		spin_unlock_irq(&mps->lock);
217
218		spi = m->spi;
219		cs_change = 1;
220		status = 0;
221		list_for_each_entry (t, &m->transfers, transfer_list) {
222			if (t->bits_per_word || t->speed_hz) {
223				status = mpc52xx_psc_spi_transfer_setup(spi, t);
224				if (status < 0)
225					break;
226			}
227
228			if (cs_change)
229				mpc52xx_psc_spi_activate_cs(spi);
230			cs_change = t->cs_change;
231
232			status = mpc52xx_psc_spi_transfer_rxtx(spi, t);
233			if (status)
234				break;
235			m->actual_length += t->len;
236
237			spi_transfer_delay_exec(t);
 
238
239			if (cs_change)
240				mpc52xx_psc_spi_deactivate_cs(spi);
241		}
242
243		m->status = status;
244		if (m->complete)
245			m->complete(m->context);
246
247		if (status || !cs_change)
248			mpc52xx_psc_spi_deactivate_cs(spi);
249
250		mpc52xx_psc_spi_transfer_setup(spi, NULL);
251
252		spin_lock_irq(&mps->lock);
253	}
254	mps->busy = 0;
255	spin_unlock_irq(&mps->lock);
256}
257
258static int mpc52xx_psc_spi_setup(struct spi_device *spi)
259{
260	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
261	struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
262	unsigned long flags;
263
264	if (spi->bits_per_word%8)
265		return -EINVAL;
266
267	if (!cs) {
268		cs = kzalloc(sizeof *cs, GFP_KERNEL);
269		if (!cs)
270			return -ENOMEM;
271		spi->controller_state = cs;
272	}
273
274	cs->bits_per_word = spi->bits_per_word;
275	cs->speed_hz = spi->max_speed_hz;
276
277	spin_lock_irqsave(&mps->lock, flags);
278	if (!mps->busy)
279		mpc52xx_psc_spi_deactivate_cs(spi);
280	spin_unlock_irqrestore(&mps->lock, flags);
281
282	return 0;
283}
284
285static int mpc52xx_psc_spi_transfer(struct spi_device *spi,
286		struct spi_message *m)
287{
288	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
289	unsigned long flags;
290
291	m->actual_length = 0;
292	m->status = -EINPROGRESS;
293
294	spin_lock_irqsave(&mps->lock, flags);
295	list_add_tail(&m->queue, &mps->queue);
296	schedule_work(&mps->work);
297	spin_unlock_irqrestore(&mps->lock, flags);
298
299	return 0;
300}
301
302static void mpc52xx_psc_spi_cleanup(struct spi_device *spi)
303{
304	kfree(spi->controller_state);
305}
306
307static int mpc52xx_psc_spi_port_config(int psc_id, struct mpc52xx_psc_spi *mps)
308{
309	struct mpc52xx_psc __iomem *psc = mps->psc;
310	struct mpc52xx_psc_fifo __iomem *fifo = mps->fifo;
311	u32 mclken_div;
312	int ret;
313
314	/* default sysclk is 512MHz */
315	mclken_div = (mps->sysclk ? mps->sysclk : 512000000) / MCLK;
316	ret = mpc52xx_set_psc_clkdiv(psc_id, mclken_div);
317	if (ret)
318		return ret;
319
320	/* Reset the PSC into a known state */
321	out_8(&psc->command, MPC52xx_PSC_RST_RX);
322	out_8(&psc->command, MPC52xx_PSC_RST_TX);
323	out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
324
325	/* Disable interrupts, interrupts are based on alarm level */
326	out_be16(&psc->mpc52xx_psc_imr, 0);
327	out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
328	out_8(&fifo->rfcntl, 0);
329	out_8(&psc->mode, MPC52xx_PSC_MODE_FFULL);
330
331	/* Configure 8bit codec mode as a SPI master and use EOF flags */
332	/* SICR_SIM_CODEC8|SICR_GENCLK|SICR_SPI|SICR_MSTR|SICR_USEEOF */
333	out_be32(&psc->sicr, 0x0180C800);
334	out_be16((u16 __iomem *)&psc->ccr, 0x070F); /* default SPI Clk 1MHz */
335
336	/* Set 2ms DTL delay */
337	out_8(&psc->ctur, 0x00);
338	out_8(&psc->ctlr, 0x84);
339
340	mps->bits_per_word = 8;
341
342	return 0;
343}
344
345static irqreturn_t mpc52xx_psc_spi_isr(int irq, void *dev_id)
346{
347	struct mpc52xx_psc_spi *mps = (struct mpc52xx_psc_spi *)dev_id;
348	struct mpc52xx_psc __iomem *psc = mps->psc;
349
350	/* disable interrupt and wake up the work queue */
351	if (in_be16(&psc->mpc52xx_psc_isr) & MPC52xx_PSC_IMR_RXRDY) {
352		out_be16(&psc->mpc52xx_psc_imr, 0);
353		complete(&mps->done);
354		return IRQ_HANDLED;
355	}
356	return IRQ_NONE;
357}
358
359/* bus_num is used only for the case dev->platform_data == NULL */
360static int mpc52xx_psc_spi_do_probe(struct device *dev, u32 regaddr,
361				u32 size, unsigned int irq, s16 bus_num)
362{
363	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
364	struct mpc52xx_psc_spi *mps;
365	struct spi_master *master;
366	int ret;
367
368	master = spi_alloc_master(dev, sizeof *mps);
369	if (master == NULL)
370		return -ENOMEM;
371
372	dev_set_drvdata(dev, master);
373	mps = spi_master_get_devdata(master);
374
375	/* the spi->mode bits understood by this driver: */
376	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
377
378	mps->irq = irq;
379	if (pdata == NULL) {
380		dev_warn(dev,
381			 "probe called without platform data, no cs_control function will be called\n");
382		mps->cs_control = NULL;
383		mps->sysclk = 0;
384		master->bus_num = bus_num;
385		master->num_chipselect = 255;
386	} else {
387		mps->cs_control = pdata->cs_control;
388		mps->sysclk = pdata->sysclk;
389		master->bus_num = pdata->bus_num;
390		master->num_chipselect = pdata->max_chipselect;
391	}
392	master->setup = mpc52xx_psc_spi_setup;
393	master->transfer = mpc52xx_psc_spi_transfer;
394	master->cleanup = mpc52xx_psc_spi_cleanup;
395	master->dev.of_node = dev->of_node;
396
397	mps->psc = ioremap(regaddr, size);
398	if (!mps->psc) {
399		dev_err(dev, "could not ioremap I/O port range\n");
400		ret = -EFAULT;
401		goto free_master;
402	}
403	/* On the 5200, fifo regs are immediately ajacent to the psc regs */
404	mps->fifo = ((void __iomem *)mps->psc) + sizeof(struct mpc52xx_psc);
405
406	ret = request_irq(mps->irq, mpc52xx_psc_spi_isr, 0, "mpc52xx-psc-spi",
407				mps);
408	if (ret)
409		goto free_master;
410
411	ret = mpc52xx_psc_spi_port_config(master->bus_num, mps);
412	if (ret < 0) {
413		dev_err(dev, "can't configure PSC! Is it capable of SPI?\n");
414		goto free_irq;
415	}
416
417	spin_lock_init(&mps->lock);
418	init_completion(&mps->done);
419	INIT_WORK(&mps->work, mpc52xx_psc_spi_work);
420	INIT_LIST_HEAD(&mps->queue);
421
 
 
 
 
 
 
 
422	ret = spi_register_master(master);
423	if (ret < 0)
424		goto free_irq;
425
426	return ret;
427
 
 
428free_irq:
429	free_irq(mps->irq, mps);
430free_master:
431	if (mps->psc)
432		iounmap(mps->psc);
433	spi_master_put(master);
434
435	return ret;
436}
437
438static int mpc52xx_psc_spi_of_probe(struct platform_device *op)
439{
440	const u32 *regaddr_p;
441	u64 regaddr64, size64;
442	s16 id = -1;
443
444	regaddr_p = of_get_address(op->dev.of_node, 0, &size64, NULL);
445	if (!regaddr_p) {
446		dev_err(&op->dev, "Invalid PSC address\n");
447		return -EINVAL;
448	}
449	regaddr64 = of_translate_address(op->dev.of_node, regaddr_p);
450
451	/* get PSC id (1..6, used by port_config) */
452	if (op->dev.platform_data == NULL) {
453		const u32 *psc_nump;
454
455		psc_nump = of_get_property(op->dev.of_node, "cell-index", NULL);
456		if (!psc_nump || *psc_nump > 5) {
457			dev_err(&op->dev, "Invalid cell-index property\n");
458			return -EINVAL;
459		}
460		id = *psc_nump + 1;
461	}
462
463	return mpc52xx_psc_spi_do_probe(&op->dev, (u32)regaddr64, (u32)size64,
464				irq_of_parse_and_map(op->dev.of_node, 0), id);
465}
466
467static int mpc52xx_psc_spi_of_remove(struct platform_device *op)
468{
469	struct spi_master *master = spi_master_get(platform_get_drvdata(op));
470	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(master);
471
472	flush_work(&mps->work);
 
473	spi_unregister_master(master);
474	free_irq(mps->irq, mps);
475	if (mps->psc)
476		iounmap(mps->psc);
477	spi_master_put(master);
478
479	return 0;
480}
481
482static const struct of_device_id mpc52xx_psc_spi_of_match[] = {
483	{ .compatible = "fsl,mpc5200-psc-spi", },
484	{ .compatible = "mpc5200-psc-spi", }, /* old */
485	{}
486};
487
488MODULE_DEVICE_TABLE(of, mpc52xx_psc_spi_of_match);
489
490static struct platform_driver mpc52xx_psc_spi_of_driver = {
491	.probe = mpc52xx_psc_spi_of_probe,
492	.remove = mpc52xx_psc_spi_of_remove,
493	.driver = {
494		.name = "mpc52xx-psc-spi",
 
495		.of_match_table = mpc52xx_psc_spi_of_match,
496	},
497};
498module_platform_driver(mpc52xx_psc_spi_of_driver);
 
 
 
 
 
 
 
 
 
 
 
499
500MODULE_AUTHOR("Dragos Carp");
501MODULE_DESCRIPTION("MPC52xx PSC SPI Driver");
502MODULE_LICENSE("GPL");
v3.1
 
  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/init.h>
 16#include <linux/types.h>
 17#include <linux/errno.h>
 18#include <linux/interrupt.h>
 19#include <linux/of_address.h>
 20#include <linux/of_platform.h>
 21#include <linux/workqueue.h>
 22#include <linux/completion.h>
 23#include <linux/io.h>
 24#include <linux/delay.h>
 25#include <linux/spi/spi.h>
 26#include <linux/fsl_devices.h>
 27#include <linux/slab.h>
 28
 29#include <asm/mpc52xx.h>
 30#include <asm/mpc52xx_psc.h>
 31
 32#define MCLK 20000000 /* PSC port MClk in hz */
 33
 34struct mpc52xx_psc_spi {
 35	/* fsl_spi_platform data */
 36	void (*cs_control)(struct spi_device *spi, bool on);
 37	u32 sysclk;
 38
 39	/* driver internal data */
 40	struct mpc52xx_psc __iomem *psc;
 41	struct mpc52xx_psc_fifo __iomem *fifo;
 42	unsigned int irq;
 43	u8 bits_per_word;
 44	u8 busy;
 45
 46	struct workqueue_struct *workqueue;
 47	struct work_struct work;
 48
 49	struct list_head queue;
 50	spinlock_t lock;
 51
 52	struct completion done;
 53};
 54
 55/* controller state */
 56struct mpc52xx_psc_spi_cs {
 57	int bits_per_word;
 58	int speed_hz;
 59};
 60
 61/* set clock freq, clock ramp, bits per work
 62 * if t is NULL then reset the values to the default values
 63 */
 64static int mpc52xx_psc_spi_transfer_setup(struct spi_device *spi,
 65		struct spi_transfer *t)
 66{
 67	struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
 68
 69	cs->speed_hz = (t && t->speed_hz)
 70			? t->speed_hz : spi->max_speed_hz;
 71	cs->bits_per_word = (t && t->bits_per_word)
 72			? t->bits_per_word : spi->bits_per_word;
 73	cs->bits_per_word = ((cs->bits_per_word + 7) / 8) * 8;
 74	return 0;
 75}
 76
 77static void mpc52xx_psc_spi_activate_cs(struct spi_device *spi)
 78{
 79	struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
 80	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
 81	struct mpc52xx_psc __iomem *psc = mps->psc;
 82	u32 sicr;
 83	u16 ccr;
 84
 85	sicr = in_be32(&psc->sicr);
 86
 87	/* Set clock phase and polarity */
 88	if (spi->mode & SPI_CPHA)
 89		sicr |= 0x00001000;
 90	else
 91		sicr &= ~0x00001000;
 92	if (spi->mode & SPI_CPOL)
 93		sicr |= 0x00002000;
 94	else
 95		sicr &= ~0x00002000;
 96
 97	if (spi->mode & SPI_LSB_FIRST)
 98		sicr |= 0x10000000;
 99	else
100		sicr &= ~0x10000000;
101	out_be32(&psc->sicr, sicr);
102
103	/* Set clock frequency and bits per word
104	 * Because psc->ccr is defined as 16bit register instead of 32bit
105	 * just set the lower byte of BitClkDiv
106	 */
107	ccr = in_be16((u16 __iomem *)&psc->ccr);
108	ccr &= 0xFF00;
109	if (cs->speed_hz)
110		ccr |= (MCLK / cs->speed_hz - 1) & 0xFF;
111	else /* by default SPI Clk 1MHz */
112		ccr |= (MCLK / 1000000 - 1) & 0xFF;
113	out_be16((u16 __iomem *)&psc->ccr, ccr);
114	mps->bits_per_word = cs->bits_per_word;
115
116	if (mps->cs_control)
117		mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 1 : 0);
118}
119
120static void mpc52xx_psc_spi_deactivate_cs(struct spi_device *spi)
121{
122	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
123
124	if (mps->cs_control)
125		mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 0 : 1);
126}
127
128#define MPC52xx_PSC_BUFSIZE (MPC52xx_PSC_RFNUM_MASK + 1)
129/* wake up when 80% fifo full */
130#define MPC52xx_PSC_RFALARM (MPC52xx_PSC_BUFSIZE * 20 / 100)
131
132static int mpc52xx_psc_spi_transfer_rxtx(struct spi_device *spi,
133						struct spi_transfer *t)
134{
135	struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
136	struct mpc52xx_psc __iomem *psc = mps->psc;
137	struct mpc52xx_psc_fifo __iomem *fifo = mps->fifo;
138	unsigned rb = 0;	/* number of bytes receieved */
139	unsigned sb = 0;	/* number of bytes sent */
140	unsigned char *rx_buf = (unsigned char *)t->rx_buf;
141	unsigned char *tx_buf = (unsigned char *)t->tx_buf;
142	unsigned rfalarm;
143	unsigned send_at_once = MPC52xx_PSC_BUFSIZE;
144	unsigned recv_at_once;
145	int last_block = 0;
146
147	if (!t->tx_buf && !t->rx_buf && t->len)
148		return -EINVAL;
149
150	/* enable transmiter/receiver */
151	out_8(&psc->command, MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE);
152	while (rb < t->len) {
153		if (t->len - rb > MPC52xx_PSC_BUFSIZE) {
154			rfalarm = MPC52xx_PSC_RFALARM;
155			last_block = 0;
156		} else {
157			send_at_once = t->len - sb;
158			rfalarm = MPC52xx_PSC_BUFSIZE - (t->len - rb);
159			last_block = 1;
160		}
161
162		dev_dbg(&spi->dev, "send %d bytes...\n", send_at_once);
163		for (; send_at_once; sb++, send_at_once--) {
164			/* set EOF flag before the last word is sent */
165			if (send_at_once == 1 && last_block)
166				out_8(&psc->ircr2, 0x01);
167
168			if (tx_buf)
169				out_8(&psc->mpc52xx_psc_buffer_8, tx_buf[sb]);
170			else
171				out_8(&psc->mpc52xx_psc_buffer_8, 0);
172		}
173
174
175		/* enable interrupts and wait for wake up
176		 * if just one byte is expected the Rx FIFO genererates no
177		 * FFULL interrupt, so activate the RxRDY interrupt
178		 */
179		out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
180		if (t->len - rb == 1) {
181			out_8(&psc->mode, 0);
182		} else {
183			out_8(&psc->mode, MPC52xx_PSC_MODE_FFULL);
184			out_be16(&fifo->rfalarm, rfalarm);
185		}
186		out_be16(&psc->mpc52xx_psc_imr, MPC52xx_PSC_IMR_RXRDY);
187		wait_for_completion(&mps->done);
188		recv_at_once = in_be16(&fifo->rfnum);
189		dev_dbg(&spi->dev, "%d bytes received\n", recv_at_once);
190
191		send_at_once = recv_at_once;
192		if (rx_buf) {
193			for (; recv_at_once; rb++, recv_at_once--)
194				rx_buf[rb] = in_8(&psc->mpc52xx_psc_buffer_8);
195		} else {
196			for (; recv_at_once; rb++, recv_at_once--)
197				in_8(&psc->mpc52xx_psc_buffer_8);
198		}
199	}
200	/* disable transmiter/receiver */
201	out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
202
203	return 0;
204}
205
206static void mpc52xx_psc_spi_work(struct work_struct *work)
207{
208	struct mpc52xx_psc_spi *mps =
209		container_of(work, struct mpc52xx_psc_spi, work);
210
211	spin_lock_irq(&mps->lock);
212	mps->busy = 1;
213	while (!list_empty(&mps->queue)) {
214		struct spi_message *m;
215		struct spi_device *spi;
216		struct spi_transfer *t = NULL;
217		unsigned cs_change;
218		int status;
219
220		m = container_of(mps->queue.next, struct spi_message, queue);
221		list_del_init(&m->queue);
222		spin_unlock_irq(&mps->lock);
223
224		spi = m->spi;
225		cs_change = 1;
226		status = 0;
227		list_for_each_entry (t, &m->transfers, transfer_list) {
228			if (t->bits_per_word || t->speed_hz) {
229				status = mpc52xx_psc_spi_transfer_setup(spi, t);
230				if (status < 0)
231					break;
232			}
233
234			if (cs_change)
235				mpc52xx_psc_spi_activate_cs(spi);
236			cs_change = t->cs_change;
237
238			status = mpc52xx_psc_spi_transfer_rxtx(spi, t);
239			if (status)
240				break;
241			m->actual_length += t->len;
242
243			if (t->delay_usecs)
244				udelay(t->delay_usecs);
245
246			if (cs_change)
247				mpc52xx_psc_spi_deactivate_cs(spi);
248		}
249
250		m->status = status;
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 __devinit 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->platform_data;
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, "probe called without platform data, no "
387				"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 __devinit 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 __devexit mpc52xx_psc_spi_of_remove(struct platform_device *op)
483{
484	struct spi_master *master = dev_get_drvdata(&op->dev);
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
494	return 0;
495}
496
497static const struct of_device_id mpc52xx_psc_spi_of_match[] = {
498	{ .compatible = "fsl,mpc5200-psc-spi", },
499	{ .compatible = "mpc5200-psc-spi", }, /* old */
500	{}
501};
502
503MODULE_DEVICE_TABLE(of, mpc52xx_psc_spi_of_match);
504
505static struct platform_driver mpc52xx_psc_spi_of_driver = {
506	.probe = mpc52xx_psc_spi_of_probe,
507	.remove = __devexit_p(mpc52xx_psc_spi_of_remove),
508	.driver = {
509		.name = "mpc52xx-psc-spi",
510		.owner = THIS_MODULE,
511		.of_match_table = mpc52xx_psc_spi_of_match,
512	},
513};
514
515static int __init mpc52xx_psc_spi_init(void)
516{
517	return platform_driver_register(&mpc52xx_psc_spi_of_driver);
518}
519module_init(mpc52xx_psc_spi_init);
520
521static void __exit mpc52xx_psc_spi_exit(void)
522{
523	platform_driver_unregister(&mpc52xx_psc_spi_of_driver);
524}
525module_exit(mpc52xx_psc_spi_exit);
526
527MODULE_AUTHOR("Dragos Carp");
528MODULE_DESCRIPTION("MPC52xx PSC SPI Driver");
529MODULE_LICENSE("GPL");