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v4.6
 
  1/*
  2 * Marvell Orion SPI controller driver
  3 *
  4 * Author: Shadi Ammouri <shadi@marvell.com>
  5 * Copyright (C) 2007-2008 Marvell Ltd.
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License version 2 as
  9 * published by the Free Software Foundation.
 10 */
 11
 12#include <linux/interrupt.h>
 13#include <linux/delay.h>
 14#include <linux/platform_device.h>
 15#include <linux/err.h>
 16#include <linux/io.h>
 17#include <linux/spi/spi.h>
 18#include <linux/module.h>
 19#include <linux/pm_runtime.h>
 20#include <linux/of.h>
 
 21#include <linux/of_device.h>
 
 22#include <linux/clk.h>
 23#include <linux/sizes.h>
 
 24#include <asm/unaligned.h>
 25
 26#define DRIVER_NAME			"orion_spi"
 27
 28/* Runtime PM autosuspend timeout: PM is fairly light on this driver */
 29#define SPI_AUTOSUSPEND_TIMEOUT		200
 30
 31/* Some SoCs using this driver support up to 8 chip selects.
 32 * It is up to the implementer to only use the chip selects
 33 * that are available.
 34 */
 35#define ORION_NUM_CHIPSELECTS		8
 36
 37#define ORION_SPI_WAIT_RDY_MAX_LOOP	2000 /* in usec */
 38
 39#define ORION_SPI_IF_CTRL_REG		0x00
 40#define ORION_SPI_IF_CONFIG_REG		0x04
 
 
 41#define ORION_SPI_DATA_OUT_REG		0x08
 42#define ORION_SPI_DATA_IN_REG		0x0c
 43#define ORION_SPI_INT_CAUSE_REG		0x10
 44#define ORION_SPI_TIMING_PARAMS_REG	0x18
 45
 
 
 
 46#define ORION_SPI_TMISO_SAMPLE_MASK	(0x3 << 6)
 47#define ORION_SPI_TMISO_SAMPLE_1	(1 << 6)
 48#define ORION_SPI_TMISO_SAMPLE_2	(2 << 6)
 49
 50#define ORION_SPI_MODE_CPOL		(1 << 11)
 51#define ORION_SPI_MODE_CPHA		(1 << 12)
 52#define ORION_SPI_IF_8_16_BIT_MODE	(1 << 5)
 53#define ORION_SPI_CLK_PRESCALE_MASK	0x1F
 54#define ARMADA_SPI_CLK_PRESCALE_MASK	0xDF
 55#define ORION_SPI_MODE_MASK		(ORION_SPI_MODE_CPOL | \
 56					 ORION_SPI_MODE_CPHA)
 57#define ORION_SPI_CS_MASK	0x1C
 58#define ORION_SPI_CS_SHIFT	2
 59#define ORION_SPI_CS(cs)	((cs << ORION_SPI_CS_SHIFT) & \
 60					ORION_SPI_CS_MASK)
 61
 62enum orion_spi_type {
 63	ORION_SPI,
 64	ARMADA_SPI,
 65};
 66
 67struct orion_spi_dev {
 68	enum orion_spi_type	typ;
 69	/*
 70	 * min_divisor and max_hz should be exclusive, the only we can
 71	 * have both is for managing the armada-370-spi case with old
 72	 * device tree
 73	 */
 74	unsigned long		max_hz;
 75	unsigned int		min_divisor;
 76	unsigned int		max_divisor;
 77	u32			prescale_mask;
 78	bool			is_errata_50mhz_ac;
 79};
 80
 
 
 
 
 
 
 
 
 
 81struct orion_spi {
 82	struct spi_master	*master;
 83	void __iomem		*base;
 84	struct clk              *clk;
 
 85	const struct orion_spi_dev *devdata;
 
 
 
 86};
 87
 88static inline void __iomem *spi_reg(struct orion_spi *orion_spi, u32 reg)
 89{
 90	return orion_spi->base + reg;
 91}
 92
 93static inline void
 94orion_spi_setbits(struct orion_spi *orion_spi, u32 reg, u32 mask)
 95{
 96	void __iomem *reg_addr = spi_reg(orion_spi, reg);
 97	u32 val;
 98
 99	val = readl(reg_addr);
100	val |= mask;
101	writel(val, reg_addr);
102}
103
104static inline void
105orion_spi_clrbits(struct orion_spi *orion_spi, u32 reg, u32 mask)
106{
107	void __iomem *reg_addr = spi_reg(orion_spi, reg);
108	u32 val;
109
110	val = readl(reg_addr);
111	val &= ~mask;
112	writel(val, reg_addr);
113}
114
115static int orion_spi_baudrate_set(struct spi_device *spi, unsigned int speed)
116{
117	u32 tclk_hz;
118	u32 rate;
119	u32 prescale;
120	u32 reg;
121	struct orion_spi *orion_spi;
122	const struct orion_spi_dev *devdata;
123
124	orion_spi = spi_master_get_devdata(spi->master);
125	devdata = orion_spi->devdata;
126
127	tclk_hz = clk_get_rate(orion_spi->clk);
128
129	if (devdata->typ == ARMADA_SPI) {
130		unsigned int clk, spr, sppr, sppr2, err;
131		unsigned int best_spr, best_sppr, best_err;
 
 
 
 
 
 
 
132
133		best_err = speed;
134		best_spr = 0;
135		best_sppr = 0;
136
137		/* Iterate over the valid range looking for best fit */
138		for (sppr = 0; sppr < 8; sppr++) {
139			sppr2 = 0x1 << sppr;
140
141			spr = tclk_hz / sppr2;
142			spr = DIV_ROUND_UP(spr, speed);
143			if ((spr == 0) || (spr > 15))
144				continue;
145
146			clk = tclk_hz / (spr * sppr2);
147			err = speed - clk;
148
149			if (err < best_err) {
150				best_spr = spr;
151				best_sppr = sppr;
152				best_err = err;
153			}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
154		}
155
156		if ((best_sppr == 0) && (best_spr == 0))
157			return -EINVAL;
158
159		prescale = ((best_sppr & 0x6) << 5) |
160			((best_sppr & 0x1) << 4) | best_spr;
161	} else {
162		/*
163		 * the supported rates are: 4,6,8...30
164		 * round up as we look for equal or less speed
165		 */
166		rate = DIV_ROUND_UP(tclk_hz, speed);
167		rate = roundup(rate, 2);
168
169		/* check if requested speed is too small */
170		if (rate > 30)
171			return -EINVAL;
172
173		if (rate < 4)
174			rate = 4;
175
176		/* Convert the rate to SPI clock divisor value.	*/
177		prescale = 0x10 + rate/2;
178	}
179
180	reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
181	reg = ((reg & ~devdata->prescale_mask) | prescale);
182	writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
183
184	return 0;
185}
186
187static void
188orion_spi_mode_set(struct spi_device *spi)
189{
190	u32 reg;
191	struct orion_spi *orion_spi;
192
193	orion_spi = spi_master_get_devdata(spi->master);
194
195	reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
196	reg &= ~ORION_SPI_MODE_MASK;
197	if (spi->mode & SPI_CPOL)
198		reg |= ORION_SPI_MODE_CPOL;
199	if (spi->mode & SPI_CPHA)
200		reg |= ORION_SPI_MODE_CPHA;
 
 
 
 
 
201	writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
202}
203
204static void
205orion_spi_50mhz_ac_timing_erratum(struct spi_device *spi, unsigned int speed)
206{
207	u32 reg;
208	struct orion_spi *orion_spi;
209
210	orion_spi = spi_master_get_devdata(spi->master);
211
212	/*
213	 * Erratum description: (Erratum NO. FE-9144572) The device
214	 * SPI interface supports frequencies of up to 50 MHz.
215	 * However, due to this erratum, when the device core clock is
216	 * 250 MHz and the SPI interfaces is configured for 50MHz SPI
217	 * clock and CPOL=CPHA=1 there might occur data corruption on
218	 * reads from the SPI device.
219	 * Erratum Workaround:
220	 * Work in one of the following configurations:
221	 * 1. Set CPOL=CPHA=0 in "SPI Interface Configuration
222	 * Register".
223	 * 2. Set TMISO_SAMPLE value to 0x2 in "SPI Timing Parameters 1
224	 * Register" before setting the interface.
225	 */
226	reg = readl(spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
227	reg &= ~ORION_SPI_TMISO_SAMPLE_MASK;
228
229	if (clk_get_rate(orion_spi->clk) == 250000000 &&
230			speed == 50000000 && spi->mode & SPI_CPOL &&
231			spi->mode & SPI_CPHA)
232		reg |= ORION_SPI_TMISO_SAMPLE_2;
233	else
234		reg |= ORION_SPI_TMISO_SAMPLE_1; /* This is the default value */
235
236	writel(reg, spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
237}
238
239/*
240 * called only when no transfer is active on the bus
241 */
242static int
243orion_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
244{
245	struct orion_spi *orion_spi;
246	unsigned int speed = spi->max_speed_hz;
247	unsigned int bits_per_word = spi->bits_per_word;
248	int	rc;
249
250	orion_spi = spi_master_get_devdata(spi->master);
251
252	if ((t != NULL) && t->speed_hz)
253		speed = t->speed_hz;
254
255	if ((t != NULL) && t->bits_per_word)
256		bits_per_word = t->bits_per_word;
257
258	orion_spi_mode_set(spi);
259
260	if (orion_spi->devdata->is_errata_50mhz_ac)
261		orion_spi_50mhz_ac_timing_erratum(spi, speed);
262
263	rc = orion_spi_baudrate_set(spi, speed);
264	if (rc)
265		return rc;
266
267	if (bits_per_word == 16)
268		orion_spi_setbits(orion_spi, ORION_SPI_IF_CONFIG_REG,
269				  ORION_SPI_IF_8_16_BIT_MODE);
270	else
271		orion_spi_clrbits(orion_spi, ORION_SPI_IF_CONFIG_REG,
272				  ORION_SPI_IF_8_16_BIT_MODE);
273
274	return 0;
275}
276
277static void orion_spi_set_cs(struct spi_device *spi, bool enable)
278{
279	struct orion_spi *orion_spi;
 
280
281	orion_spi = spi_master_get_devdata(spi->master);
282
 
 
 
 
 
283	orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, ORION_SPI_CS_MASK);
284	orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG,
285				ORION_SPI_CS(spi->chip_select));
286
287	/* Chip select logic is inverted from spi_set_cs */
288	if (!enable)
289		orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
290	else
291		orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
292}
293
294static inline int orion_spi_wait_till_ready(struct orion_spi *orion_spi)
295{
296	int i;
297
298	for (i = 0; i < ORION_SPI_WAIT_RDY_MAX_LOOP; i++) {
299		if (readl(spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG)))
300			return 1;
301
302		udelay(1);
303	}
304
305	return -1;
306}
307
308static inline int
309orion_spi_write_read_8bit(struct spi_device *spi,
310			  const u8 **tx_buf, u8 **rx_buf)
311{
312	void __iomem *tx_reg, *rx_reg, *int_reg;
313	struct orion_spi *orion_spi;
314
315	orion_spi = spi_master_get_devdata(spi->master);
316	tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG);
317	rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG);
318	int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG);
319
320	/* clear the interrupt cause register */
321	writel(0x0, int_reg);
322
323	if (tx_buf && *tx_buf)
324		writel(*(*tx_buf)++, tx_reg);
325	else
326		writel(0, tx_reg);
327
328	if (orion_spi_wait_till_ready(orion_spi) < 0) {
329		dev_err(&spi->dev, "TXS timed out\n");
330		return -1;
331	}
332
333	if (rx_buf && *rx_buf)
334		*(*rx_buf)++ = readl(rx_reg);
335
336	return 1;
337}
338
339static inline int
340orion_spi_write_read_16bit(struct spi_device *spi,
341			   const u16 **tx_buf, u16 **rx_buf)
342{
343	void __iomem *tx_reg, *rx_reg, *int_reg;
344	struct orion_spi *orion_spi;
345
346	orion_spi = spi_master_get_devdata(spi->master);
347	tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG);
348	rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG);
349	int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG);
350
351	/* clear the interrupt cause register */
352	writel(0x0, int_reg);
353
354	if (tx_buf && *tx_buf)
355		writel(__cpu_to_le16(get_unaligned((*tx_buf)++)), tx_reg);
356	else
357		writel(0, tx_reg);
358
359	if (orion_spi_wait_till_ready(orion_spi) < 0) {
360		dev_err(&spi->dev, "TXS timed out\n");
361		return -1;
362	}
363
364	if (rx_buf && *rx_buf)
365		put_unaligned(__le16_to_cpu(readl(rx_reg)), (*rx_buf)++);
366
367	return 1;
368}
369
370static unsigned int
371orion_spi_write_read(struct spi_device *spi, struct spi_transfer *xfer)
372{
373	unsigned int count;
374	int word_len;
 
 
 
375
376	word_len = spi->bits_per_word;
377	count = xfer->len;
378
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
379	if (word_len == 8) {
380		const u8 *tx = xfer->tx_buf;
381		u8 *rx = xfer->rx_buf;
382
383		do {
384			if (orion_spi_write_read_8bit(spi, &tx, &rx) < 0)
385				goto out;
386			count--;
 
 
387		} while (count);
388	} else if (word_len == 16) {
389		const u16 *tx = xfer->tx_buf;
390		u16 *rx = xfer->rx_buf;
391
392		do {
393			if (orion_spi_write_read_16bit(spi, &tx, &rx) < 0)
394				goto out;
395			count -= 2;
 
 
396		} while (count);
397	}
398
399out:
400	return xfer->len - count;
401}
402
403static int orion_spi_transfer_one(struct spi_master *master,
404					struct spi_device *spi,
405					struct spi_transfer *t)
406{
407	int status = 0;
408
409	status = orion_spi_setup_transfer(spi, t);
410	if (status < 0)
411		return status;
412
413	if (t->len)
414		orion_spi_write_read(spi, t);
415
416	return status;
417}
418
419static int orion_spi_setup(struct spi_device *spi)
420{
 
 
 
421	return orion_spi_setup_transfer(spi, NULL);
422}
423
424static int orion_spi_reset(struct orion_spi *orion_spi)
425{
426	/* Verify that the CS is deasserted */
427	orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
 
 
 
 
428	return 0;
429}
430
431static const struct orion_spi_dev orion_spi_dev_data = {
432	.typ = ORION_SPI,
433	.min_divisor = 4,
434	.max_divisor = 30,
435	.prescale_mask = ORION_SPI_CLK_PRESCALE_MASK,
436};
437
438static const struct orion_spi_dev armada_370_spi_dev_data = {
439	.typ = ARMADA_SPI,
440	.min_divisor = 4,
441	.max_divisor = 1920,
442	.max_hz = 50000000,
443	.prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
444};
445
446static const struct orion_spi_dev armada_xp_spi_dev_data = {
447	.typ = ARMADA_SPI,
448	.max_hz = 50000000,
449	.max_divisor = 1920,
450	.prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
451};
452
453static const struct orion_spi_dev armada_375_spi_dev_data = {
454	.typ = ARMADA_SPI,
455	.min_divisor = 15,
456	.max_divisor = 1920,
457	.prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
458};
459
460static const struct orion_spi_dev armada_380_spi_dev_data = {
461	.typ = ARMADA_SPI,
462	.max_hz = 50000000,
463	.max_divisor = 1920,
464	.prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
465	.is_errata_50mhz_ac = true,
466};
467
468static const struct of_device_id orion_spi_of_match_table[] = {
469	{
470		.compatible = "marvell,orion-spi",
471		.data = &orion_spi_dev_data,
472	},
473	{
474		.compatible = "marvell,armada-370-spi",
475		.data = &armada_370_spi_dev_data,
476	},
477	{
478		.compatible = "marvell,armada-375-spi",
479		.data = &armada_375_spi_dev_data,
480	},
481	{
482		.compatible = "marvell,armada-380-spi",
483		.data = &armada_380_spi_dev_data,
484	},
485	{
486		.compatible = "marvell,armada-390-spi",
487		.data = &armada_xp_spi_dev_data,
488	},
489	{
490		.compatible = "marvell,armada-xp-spi",
491		.data = &armada_xp_spi_dev_data,
492	},
493
494	{}
495};
496MODULE_DEVICE_TABLE(of, orion_spi_of_match_table);
497
498static int orion_spi_probe(struct platform_device *pdev)
499{
500	const struct of_device_id *of_id;
501	const struct orion_spi_dev *devdata;
502	struct spi_master *master;
503	struct orion_spi *spi;
504	struct resource *r;
505	unsigned long tclk_hz;
506	int status = 0;
 
507
508	master = spi_alloc_master(&pdev->dev, sizeof(*spi));
509	if (master == NULL) {
510		dev_dbg(&pdev->dev, "master allocation failed\n");
511		return -ENOMEM;
512	}
513
514	if (pdev->id != -1)
515		master->bus_num = pdev->id;
516	if (pdev->dev.of_node) {
517		u32 cell_index;
518
519		if (!of_property_read_u32(pdev->dev.of_node, "cell-index",
520					  &cell_index))
521			master->bus_num = cell_index;
522	}
523
524	/* we support only mode 0, and no options */
525	master->mode_bits = SPI_CPHA | SPI_CPOL;
526	master->set_cs = orion_spi_set_cs;
527	master->transfer_one = orion_spi_transfer_one;
528	master->num_chipselect = ORION_NUM_CHIPSELECTS;
529	master->setup = orion_spi_setup;
530	master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
531	master->auto_runtime_pm = true;
 
532
533	platform_set_drvdata(pdev, master);
534
535	spi = spi_master_get_devdata(master);
536	spi->master = master;
 
537
538	of_id = of_match_device(orion_spi_of_match_table, &pdev->dev);
539	devdata = (of_id) ? of_id->data : &orion_spi_dev_data;
540	spi->devdata = devdata;
541
542	spi->clk = devm_clk_get(&pdev->dev, NULL);
543	if (IS_ERR(spi->clk)) {
544		status = PTR_ERR(spi->clk);
545		goto out;
546	}
547
548	status = clk_prepare_enable(spi->clk);
549	if (status)
550		goto out;
551
 
 
 
 
 
 
 
 
 
 
552	tclk_hz = clk_get_rate(spi->clk);
553
554	/*
555	 * With old device tree, armada-370-spi could be used with
556	 * Armada XP, however for this SoC the maximum frequency is
557	 * 50MHz instead of tclk/4. On Armada 370, tclk cannot be
558	 * higher than 200MHz. So, in order to be able to handle both
559	 * SoCs, we can take the minimum of 50MHz and tclk/4.
560	 */
561	if (of_device_is_compatible(pdev->dev.of_node,
562					"marvell,armada-370-spi"))
563		master->max_speed_hz = min(devdata->max_hz,
564				DIV_ROUND_UP(tclk_hz, devdata->min_divisor));
565	else if (devdata->min_divisor)
566		master->max_speed_hz =
567			DIV_ROUND_UP(tclk_hz, devdata->min_divisor);
568	else
569		master->max_speed_hz = devdata->max_hz;
570	master->min_speed_hz = DIV_ROUND_UP(tclk_hz, devdata->max_divisor);
571
572	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
573	spi->base = devm_ioremap_resource(&pdev->dev, r);
574	if (IS_ERR(spi->base)) {
575		status = PTR_ERR(spi->base);
576		goto out_rel_clk;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
577	}
578
579	pm_runtime_set_active(&pdev->dev);
580	pm_runtime_use_autosuspend(&pdev->dev);
581	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
582	pm_runtime_enable(&pdev->dev);
583
584	status = orion_spi_reset(spi);
585	if (status < 0)
586		goto out_rel_pm;
587
588	pm_runtime_mark_last_busy(&pdev->dev);
589	pm_runtime_put_autosuspend(&pdev->dev);
590
591	master->dev.of_node = pdev->dev.of_node;
592	status = spi_register_master(master);
593	if (status < 0)
594		goto out_rel_pm;
595
596	return status;
597
598out_rel_pm:
599	pm_runtime_disable(&pdev->dev);
 
 
600out_rel_clk:
601	clk_disable_unprepare(spi->clk);
602out:
603	spi_master_put(master);
604	return status;
605}
606
607
608static int orion_spi_remove(struct platform_device *pdev)
609{
610	struct spi_master *master = platform_get_drvdata(pdev);
611	struct orion_spi *spi = spi_master_get_devdata(master);
612
613	pm_runtime_get_sync(&pdev->dev);
 
614	clk_disable_unprepare(spi->clk);
615
616	spi_unregister_master(master);
617	pm_runtime_disable(&pdev->dev);
618
619	return 0;
620}
621
622MODULE_ALIAS("platform:" DRIVER_NAME);
623
624#ifdef CONFIG_PM
625static int orion_spi_runtime_suspend(struct device *dev)
626{
627	struct spi_master *master = dev_get_drvdata(dev);
628	struct orion_spi *spi = spi_master_get_devdata(master);
629
 
630	clk_disable_unprepare(spi->clk);
631	return 0;
632}
633
634static int orion_spi_runtime_resume(struct device *dev)
635{
636	struct spi_master *master = dev_get_drvdata(dev);
637	struct orion_spi *spi = spi_master_get_devdata(master);
638
 
 
639	return clk_prepare_enable(spi->clk);
640}
641#endif
642
643static const struct dev_pm_ops orion_spi_pm_ops = {
644	SET_RUNTIME_PM_OPS(orion_spi_runtime_suspend,
645			   orion_spi_runtime_resume,
646			   NULL)
647};
648
649static struct platform_driver orion_spi_driver = {
650	.driver = {
651		.name	= DRIVER_NAME,
652		.pm	= &orion_spi_pm_ops,
653		.of_match_table = of_match_ptr(orion_spi_of_match_table),
654	},
655	.probe		= orion_spi_probe,
656	.remove		= orion_spi_remove,
657};
658
659module_platform_driver(orion_spi_driver);
660
661MODULE_DESCRIPTION("Orion SPI driver");
662MODULE_AUTHOR("Shadi Ammouri <shadi@marvell.com>");
663MODULE_LICENSE("GPL");
v5.4
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Marvell Orion SPI controller driver
  4 *
  5 * Author: Shadi Ammouri <shadi@marvell.com>
  6 * Copyright (C) 2007-2008 Marvell Ltd.
 
 
 
 
  7 */
  8
  9#include <linux/interrupt.h>
 10#include <linux/delay.h>
 11#include <linux/platform_device.h>
 12#include <linux/err.h>
 13#include <linux/io.h>
 14#include <linux/spi/spi.h>
 15#include <linux/module.h>
 16#include <linux/pm_runtime.h>
 17#include <linux/of.h>
 18#include <linux/of_address.h>
 19#include <linux/of_device.h>
 20#include <linux/of_gpio.h>
 21#include <linux/clk.h>
 22#include <linux/sizes.h>
 23#include <linux/gpio.h>
 24#include <asm/unaligned.h>
 25
 26#define DRIVER_NAME			"orion_spi"
 27
 28/* Runtime PM autosuspend timeout: PM is fairly light on this driver */
 29#define SPI_AUTOSUSPEND_TIMEOUT		200
 30
 31/* Some SoCs using this driver support up to 8 chip selects.
 32 * It is up to the implementer to only use the chip selects
 33 * that are available.
 34 */
 35#define ORION_NUM_CHIPSELECTS		8
 36
 37#define ORION_SPI_WAIT_RDY_MAX_LOOP	2000 /* in usec */
 38
 39#define ORION_SPI_IF_CTRL_REG		0x00
 40#define ORION_SPI_IF_CONFIG_REG		0x04
 41#define ORION_SPI_IF_RXLSBF		BIT(14)
 42#define ORION_SPI_IF_TXLSBF		BIT(13)
 43#define ORION_SPI_DATA_OUT_REG		0x08
 44#define ORION_SPI_DATA_IN_REG		0x0c
 45#define ORION_SPI_INT_CAUSE_REG		0x10
 46#define ORION_SPI_TIMING_PARAMS_REG	0x18
 47
 48/* Register for the "Direct Mode" */
 49#define SPI_DIRECT_WRITE_CONFIG_REG	0x20
 50
 51#define ORION_SPI_TMISO_SAMPLE_MASK	(0x3 << 6)
 52#define ORION_SPI_TMISO_SAMPLE_1	(1 << 6)
 53#define ORION_SPI_TMISO_SAMPLE_2	(2 << 6)
 54
 55#define ORION_SPI_MODE_CPOL		(1 << 11)
 56#define ORION_SPI_MODE_CPHA		(1 << 12)
 57#define ORION_SPI_IF_8_16_BIT_MODE	(1 << 5)
 58#define ORION_SPI_CLK_PRESCALE_MASK	0x1F
 59#define ARMADA_SPI_CLK_PRESCALE_MASK	0xDF
 60#define ORION_SPI_MODE_MASK		(ORION_SPI_MODE_CPOL | \
 61					 ORION_SPI_MODE_CPHA)
 62#define ORION_SPI_CS_MASK	0x1C
 63#define ORION_SPI_CS_SHIFT	2
 64#define ORION_SPI_CS(cs)	((cs << ORION_SPI_CS_SHIFT) & \
 65					ORION_SPI_CS_MASK)
 66
 67enum orion_spi_type {
 68	ORION_SPI,
 69	ARMADA_SPI,
 70};
 71
 72struct orion_spi_dev {
 73	enum orion_spi_type	typ;
 74	/*
 75	 * min_divisor and max_hz should be exclusive, the only we can
 76	 * have both is for managing the armada-370-spi case with old
 77	 * device tree
 78	 */
 79	unsigned long		max_hz;
 80	unsigned int		min_divisor;
 81	unsigned int		max_divisor;
 82	u32			prescale_mask;
 83	bool			is_errata_50mhz_ac;
 84};
 85
 86struct orion_direct_acc {
 87	void __iomem		*vaddr;
 88	u32			size;
 89};
 90
 91struct orion_child_options {
 92	struct orion_direct_acc direct_access;
 93};
 94
 95struct orion_spi {
 96	struct spi_master	*master;
 97	void __iomem		*base;
 98	struct clk              *clk;
 99	struct clk              *axi_clk;
100	const struct orion_spi_dev *devdata;
101	int			unused_hw_gpio;
102
103	struct orion_child_options	child[ORION_NUM_CHIPSELECTS];
104};
105
106static inline void __iomem *spi_reg(struct orion_spi *orion_spi, u32 reg)
107{
108	return orion_spi->base + reg;
109}
110
111static inline void
112orion_spi_setbits(struct orion_spi *orion_spi, u32 reg, u32 mask)
113{
114	void __iomem *reg_addr = spi_reg(orion_spi, reg);
115	u32 val;
116
117	val = readl(reg_addr);
118	val |= mask;
119	writel(val, reg_addr);
120}
121
122static inline void
123orion_spi_clrbits(struct orion_spi *orion_spi, u32 reg, u32 mask)
124{
125	void __iomem *reg_addr = spi_reg(orion_spi, reg);
126	u32 val;
127
128	val = readl(reg_addr);
129	val &= ~mask;
130	writel(val, reg_addr);
131}
132
133static int orion_spi_baudrate_set(struct spi_device *spi, unsigned int speed)
134{
135	u32 tclk_hz;
136	u32 rate;
137	u32 prescale;
138	u32 reg;
139	struct orion_spi *orion_spi;
140	const struct orion_spi_dev *devdata;
141
142	orion_spi = spi_master_get_devdata(spi->master);
143	devdata = orion_spi->devdata;
144
145	tclk_hz = clk_get_rate(orion_spi->clk);
146
147	if (devdata->typ == ARMADA_SPI) {
148		/*
149		 * Given the core_clk (tclk_hz) and the target rate (speed) we
150		 * determine the best values for SPR (in [0 .. 15]) and SPPR (in
151		 * [0..7]) such that
152		 *
153		 * 	core_clk / (SPR * 2 ** SPPR)
154		 *
155		 * is as big as possible but not bigger than speed.
156		 */
157
158		/* best integer divider: */
159		unsigned divider = DIV_ROUND_UP(tclk_hz, speed);
160		unsigned spr, sppr;
161
162		if (divider < 16) {
163			/* This is the easy case, divider is less than 16 */
164			spr = divider;
165			sppr = 0;
166
167		} else {
168			unsigned two_pow_sppr;
169			/*
170			 * Find the highest bit set in divider. This and the
171			 * three next bits define SPR (apart from rounding).
172			 * SPPR is then the number of zero bits that must be
173			 * appended:
174			 */
175			sppr = fls(divider) - 4;
176
177			/*
178			 * As SPR only has 4 bits, we have to round divider up
179			 * to the next multiple of 2 ** sppr.
180			 */
181			two_pow_sppr = 1 << sppr;
182			divider = (divider + two_pow_sppr - 1) & -two_pow_sppr;
183
184			/*
185			 * recalculate sppr as rounding up divider might have
186			 * increased it enough to change the position of the
187			 * highest set bit. In this case the bit that now
188			 * doesn't make it into SPR is 0, so there is no need to
189			 * round again.
190			 */
191			sppr = fls(divider) - 4;
192			spr = divider >> sppr;
193
194			/*
195			 * Now do range checking. SPR is constructed to have a
196			 * width of 4 bits, so this is fine for sure. So we
197			 * still need to check for sppr to fit into 3 bits:
198			 */
199			if (sppr > 7)
200				return -EINVAL;
201		}
202
203		prescale = ((sppr & 0x6) << 5) | ((sppr & 0x1) << 4) | spr;
 
 
 
 
204	} else {
205		/*
206		 * the supported rates are: 4,6,8...30
207		 * round up as we look for equal or less speed
208		 */
209		rate = DIV_ROUND_UP(tclk_hz, speed);
210		rate = roundup(rate, 2);
211
212		/* check if requested speed is too small */
213		if (rate > 30)
214			return -EINVAL;
215
216		if (rate < 4)
217			rate = 4;
218
219		/* Convert the rate to SPI clock divisor value.	*/
220		prescale = 0x10 + rate/2;
221	}
222
223	reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
224	reg = ((reg & ~devdata->prescale_mask) | prescale);
225	writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
226
227	return 0;
228}
229
230static void
231orion_spi_mode_set(struct spi_device *spi)
232{
233	u32 reg;
234	struct orion_spi *orion_spi;
235
236	orion_spi = spi_master_get_devdata(spi->master);
237
238	reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
239	reg &= ~ORION_SPI_MODE_MASK;
240	if (spi->mode & SPI_CPOL)
241		reg |= ORION_SPI_MODE_CPOL;
242	if (spi->mode & SPI_CPHA)
243		reg |= ORION_SPI_MODE_CPHA;
244	if (spi->mode & SPI_LSB_FIRST)
245		reg |= ORION_SPI_IF_RXLSBF | ORION_SPI_IF_TXLSBF;
246	else
247		reg &= ~(ORION_SPI_IF_RXLSBF | ORION_SPI_IF_TXLSBF);
248
249	writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
250}
251
252static void
253orion_spi_50mhz_ac_timing_erratum(struct spi_device *spi, unsigned int speed)
254{
255	u32 reg;
256	struct orion_spi *orion_spi;
257
258	orion_spi = spi_master_get_devdata(spi->master);
259
260	/*
261	 * Erratum description: (Erratum NO. FE-9144572) The device
262	 * SPI interface supports frequencies of up to 50 MHz.
263	 * However, due to this erratum, when the device core clock is
264	 * 250 MHz and the SPI interfaces is configured for 50MHz SPI
265	 * clock and CPOL=CPHA=1 there might occur data corruption on
266	 * reads from the SPI device.
267	 * Erratum Workaround:
268	 * Work in one of the following configurations:
269	 * 1. Set CPOL=CPHA=0 in "SPI Interface Configuration
270	 * Register".
271	 * 2. Set TMISO_SAMPLE value to 0x2 in "SPI Timing Parameters 1
272	 * Register" before setting the interface.
273	 */
274	reg = readl(spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
275	reg &= ~ORION_SPI_TMISO_SAMPLE_MASK;
276
277	if (clk_get_rate(orion_spi->clk) == 250000000 &&
278			speed == 50000000 && spi->mode & SPI_CPOL &&
279			spi->mode & SPI_CPHA)
280		reg |= ORION_SPI_TMISO_SAMPLE_2;
281	else
282		reg |= ORION_SPI_TMISO_SAMPLE_1; /* This is the default value */
283
284	writel(reg, spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
285}
286
287/*
288 * called only when no transfer is active on the bus
289 */
290static int
291orion_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
292{
293	struct orion_spi *orion_spi;
294	unsigned int speed = spi->max_speed_hz;
295	unsigned int bits_per_word = spi->bits_per_word;
296	int	rc;
297
298	orion_spi = spi_master_get_devdata(spi->master);
299
300	if ((t != NULL) && t->speed_hz)
301		speed = t->speed_hz;
302
303	if ((t != NULL) && t->bits_per_word)
304		bits_per_word = t->bits_per_word;
305
306	orion_spi_mode_set(spi);
307
308	if (orion_spi->devdata->is_errata_50mhz_ac)
309		orion_spi_50mhz_ac_timing_erratum(spi, speed);
310
311	rc = orion_spi_baudrate_set(spi, speed);
312	if (rc)
313		return rc;
314
315	if (bits_per_word == 16)
316		orion_spi_setbits(orion_spi, ORION_SPI_IF_CONFIG_REG,
317				  ORION_SPI_IF_8_16_BIT_MODE);
318	else
319		orion_spi_clrbits(orion_spi, ORION_SPI_IF_CONFIG_REG,
320				  ORION_SPI_IF_8_16_BIT_MODE);
321
322	return 0;
323}
324
325static void orion_spi_set_cs(struct spi_device *spi, bool enable)
326{
327	struct orion_spi *orion_spi;
328	int cs;
329
330	orion_spi = spi_master_get_devdata(spi->master);
331
332	if (gpio_is_valid(spi->cs_gpio))
333		cs = orion_spi->unused_hw_gpio;
334	else
335		cs = spi->chip_select;
336
337	orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, ORION_SPI_CS_MASK);
338	orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG,
339				ORION_SPI_CS(cs));
340
341	/* Chip select logic is inverted from spi_set_cs */
342	if (!enable)
343		orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
344	else
345		orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
346}
347
348static inline int orion_spi_wait_till_ready(struct orion_spi *orion_spi)
349{
350	int i;
351
352	for (i = 0; i < ORION_SPI_WAIT_RDY_MAX_LOOP; i++) {
353		if (readl(spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG)))
354			return 1;
355
356		udelay(1);
357	}
358
359	return -1;
360}
361
362static inline int
363orion_spi_write_read_8bit(struct spi_device *spi,
364			  const u8 **tx_buf, u8 **rx_buf)
365{
366	void __iomem *tx_reg, *rx_reg, *int_reg;
367	struct orion_spi *orion_spi;
368
369	orion_spi = spi_master_get_devdata(spi->master);
370	tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG);
371	rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG);
372	int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG);
373
374	/* clear the interrupt cause register */
375	writel(0x0, int_reg);
376
377	if (tx_buf && *tx_buf)
378		writel(*(*tx_buf)++, tx_reg);
379	else
380		writel(0, tx_reg);
381
382	if (orion_spi_wait_till_ready(orion_spi) < 0) {
383		dev_err(&spi->dev, "TXS timed out\n");
384		return -1;
385	}
386
387	if (rx_buf && *rx_buf)
388		*(*rx_buf)++ = readl(rx_reg);
389
390	return 1;
391}
392
393static inline int
394orion_spi_write_read_16bit(struct spi_device *spi,
395			   const u16 **tx_buf, u16 **rx_buf)
396{
397	void __iomem *tx_reg, *rx_reg, *int_reg;
398	struct orion_spi *orion_spi;
399
400	orion_spi = spi_master_get_devdata(spi->master);
401	tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG);
402	rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG);
403	int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG);
404
405	/* clear the interrupt cause register */
406	writel(0x0, int_reg);
407
408	if (tx_buf && *tx_buf)
409		writel(__cpu_to_le16(get_unaligned((*tx_buf)++)), tx_reg);
410	else
411		writel(0, tx_reg);
412
413	if (orion_spi_wait_till_ready(orion_spi) < 0) {
414		dev_err(&spi->dev, "TXS timed out\n");
415		return -1;
416	}
417
418	if (rx_buf && *rx_buf)
419		put_unaligned(__le16_to_cpu(readl(rx_reg)), (*rx_buf)++);
420
421	return 1;
422}
423
424static unsigned int
425orion_spi_write_read(struct spi_device *spi, struct spi_transfer *xfer)
426{
427	unsigned int count;
428	int word_len;
429	struct orion_spi *orion_spi;
430	int cs = spi->chip_select;
431	void __iomem *vaddr;
432
433	word_len = spi->bits_per_word;
434	count = xfer->len;
435
436	orion_spi = spi_master_get_devdata(spi->master);
437
438	/*
439	 * Use SPI direct write mode if base address is available. Otherwise
440	 * fall back to PIO mode for this transfer.
441	 */
442	vaddr = orion_spi->child[cs].direct_access.vaddr;
443
444	if (vaddr && xfer->tx_buf && word_len == 8) {
445		unsigned int cnt = count / 4;
446		unsigned int rem = count % 4;
447
448		/*
449		 * Send the TX-data to the SPI device via the direct
450		 * mapped address window
451		 */
452		iowrite32_rep(vaddr, xfer->tx_buf, cnt);
453		if (rem) {
454			u32 *buf = (u32 *)xfer->tx_buf;
455
456			iowrite8_rep(vaddr, &buf[cnt], rem);
457		}
458
459		return count;
460	}
461
462	if (word_len == 8) {
463		const u8 *tx = xfer->tx_buf;
464		u8 *rx = xfer->rx_buf;
465
466		do {
467			if (orion_spi_write_read_8bit(spi, &tx, &rx) < 0)
468				goto out;
469			count--;
470			if (xfer->word_delay_usecs)
471				udelay(xfer->word_delay_usecs);
472		} while (count);
473	} else if (word_len == 16) {
474		const u16 *tx = xfer->tx_buf;
475		u16 *rx = xfer->rx_buf;
476
477		do {
478			if (orion_spi_write_read_16bit(spi, &tx, &rx) < 0)
479				goto out;
480			count -= 2;
481			if (xfer->word_delay_usecs)
482				udelay(xfer->word_delay_usecs);
483		} while (count);
484	}
485
486out:
487	return xfer->len - count;
488}
489
490static int orion_spi_transfer_one(struct spi_master *master,
491					struct spi_device *spi,
492					struct spi_transfer *t)
493{
494	int status = 0;
495
496	status = orion_spi_setup_transfer(spi, t);
497	if (status < 0)
498		return status;
499
500	if (t->len)
501		orion_spi_write_read(spi, t);
502
503	return status;
504}
505
506static int orion_spi_setup(struct spi_device *spi)
507{
508	if (gpio_is_valid(spi->cs_gpio)) {
509		gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
510	}
511	return orion_spi_setup_transfer(spi, NULL);
512}
513
514static int orion_spi_reset(struct orion_spi *orion_spi)
515{
516	/* Verify that the CS is deasserted */
517	orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
518
519	/* Don't deassert CS between the direct mapped SPI transfers */
520	writel(0, spi_reg(orion_spi, SPI_DIRECT_WRITE_CONFIG_REG));
521
522	return 0;
523}
524
525static const struct orion_spi_dev orion_spi_dev_data = {
526	.typ = ORION_SPI,
527	.min_divisor = 4,
528	.max_divisor = 30,
529	.prescale_mask = ORION_SPI_CLK_PRESCALE_MASK,
530};
531
532static const struct orion_spi_dev armada_370_spi_dev_data = {
533	.typ = ARMADA_SPI,
534	.min_divisor = 4,
535	.max_divisor = 1920,
536	.max_hz = 50000000,
537	.prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
538};
539
540static const struct orion_spi_dev armada_xp_spi_dev_data = {
541	.typ = ARMADA_SPI,
542	.max_hz = 50000000,
543	.max_divisor = 1920,
544	.prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
545};
546
547static const struct orion_spi_dev armada_375_spi_dev_data = {
548	.typ = ARMADA_SPI,
549	.min_divisor = 15,
550	.max_divisor = 1920,
551	.prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
552};
553
554static const struct orion_spi_dev armada_380_spi_dev_data = {
555	.typ = ARMADA_SPI,
556	.max_hz = 50000000,
557	.max_divisor = 1920,
558	.prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
559	.is_errata_50mhz_ac = true,
560};
561
562static const struct of_device_id orion_spi_of_match_table[] = {
563	{
564		.compatible = "marvell,orion-spi",
565		.data = &orion_spi_dev_data,
566	},
567	{
568		.compatible = "marvell,armada-370-spi",
569		.data = &armada_370_spi_dev_data,
570	},
571	{
572		.compatible = "marvell,armada-375-spi",
573		.data = &armada_375_spi_dev_data,
574	},
575	{
576		.compatible = "marvell,armada-380-spi",
577		.data = &armada_380_spi_dev_data,
578	},
579	{
580		.compatible = "marvell,armada-390-spi",
581		.data = &armada_xp_spi_dev_data,
582	},
583	{
584		.compatible = "marvell,armada-xp-spi",
585		.data = &armada_xp_spi_dev_data,
586	},
587
588	{}
589};
590MODULE_DEVICE_TABLE(of, orion_spi_of_match_table);
591
592static int orion_spi_probe(struct platform_device *pdev)
593{
594	const struct of_device_id *of_id;
595	const struct orion_spi_dev *devdata;
596	struct spi_master *master;
597	struct orion_spi *spi;
598	struct resource *r;
599	unsigned long tclk_hz;
600	int status = 0;
601	struct device_node *np;
602
603	master = spi_alloc_master(&pdev->dev, sizeof(*spi));
604	if (master == NULL) {
605		dev_dbg(&pdev->dev, "master allocation failed\n");
606		return -ENOMEM;
607	}
608
609	if (pdev->id != -1)
610		master->bus_num = pdev->id;
611	if (pdev->dev.of_node) {
612		u32 cell_index;
613
614		if (!of_property_read_u32(pdev->dev.of_node, "cell-index",
615					  &cell_index))
616			master->bus_num = cell_index;
617	}
618
619	/* we support all 4 SPI modes and LSB first option */
620	master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_LSB_FIRST;
621	master->set_cs = orion_spi_set_cs;
622	master->transfer_one = orion_spi_transfer_one;
623	master->num_chipselect = ORION_NUM_CHIPSELECTS;
624	master->setup = orion_spi_setup;
625	master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
626	master->auto_runtime_pm = true;
627	master->flags = SPI_MASTER_GPIO_SS;
628
629	platform_set_drvdata(pdev, master);
630
631	spi = spi_master_get_devdata(master);
632	spi->master = master;
633	spi->unused_hw_gpio = -1;
634
635	of_id = of_match_device(orion_spi_of_match_table, &pdev->dev);
636	devdata = (of_id) ? of_id->data : &orion_spi_dev_data;
637	spi->devdata = devdata;
638
639	spi->clk = devm_clk_get(&pdev->dev, NULL);
640	if (IS_ERR(spi->clk)) {
641		status = PTR_ERR(spi->clk);
642		goto out;
643	}
644
645	status = clk_prepare_enable(spi->clk);
646	if (status)
647		goto out;
648
649	/* The following clock is only used by some SoCs */
650	spi->axi_clk = devm_clk_get(&pdev->dev, "axi");
651	if (IS_ERR(spi->axi_clk) &&
652	    PTR_ERR(spi->axi_clk) == -EPROBE_DEFER) {
653		status = -EPROBE_DEFER;
654		goto out_rel_clk;
655	}
656	if (!IS_ERR(spi->axi_clk))
657		clk_prepare_enable(spi->axi_clk);
658
659	tclk_hz = clk_get_rate(spi->clk);
660
661	/*
662	 * With old device tree, armada-370-spi could be used with
663	 * Armada XP, however for this SoC the maximum frequency is
664	 * 50MHz instead of tclk/4. On Armada 370, tclk cannot be
665	 * higher than 200MHz. So, in order to be able to handle both
666	 * SoCs, we can take the minimum of 50MHz and tclk/4.
667	 */
668	if (of_device_is_compatible(pdev->dev.of_node,
669					"marvell,armada-370-spi"))
670		master->max_speed_hz = min(devdata->max_hz,
671				DIV_ROUND_UP(tclk_hz, devdata->min_divisor));
672	else if (devdata->min_divisor)
673		master->max_speed_hz =
674			DIV_ROUND_UP(tclk_hz, devdata->min_divisor);
675	else
676		master->max_speed_hz = devdata->max_hz;
677	master->min_speed_hz = DIV_ROUND_UP(tclk_hz, devdata->max_divisor);
678
679	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
680	spi->base = devm_ioremap_resource(&pdev->dev, r);
681	if (IS_ERR(spi->base)) {
682		status = PTR_ERR(spi->base);
683		goto out_rel_axi_clk;
684	}
685
686	for_each_available_child_of_node(pdev->dev.of_node, np) {
687		struct orion_direct_acc *dir_acc;
688		u32 cs;
689		int cs_gpio;
690
691		/* Get chip-select number from the "reg" property */
692		status = of_property_read_u32(np, "reg", &cs);
693		if (status) {
694			dev_err(&pdev->dev,
695				"%pOF has no valid 'reg' property (%d)\n",
696				np, status);
697			continue;
698		}
699
700		/*
701		 * Initialize the CS GPIO:
702		 * - properly request the actual GPIO signal
703		 * - de-assert the logical signal so that all GPIO CS lines
704		 *   are inactive when probing for slaves
705		 * - find an unused physical CS which will be driven for any
706		 *   slave which uses a CS GPIO
707		 */
708		cs_gpio = of_get_named_gpio(pdev->dev.of_node, "cs-gpios", cs);
709		if (cs_gpio > 0) {
710			char *gpio_name;
711			int cs_flags;
712
713			if (spi->unused_hw_gpio == -1) {
714				dev_info(&pdev->dev,
715					"Selected unused HW CS#%d for any GPIO CSes\n",
716					cs);
717				spi->unused_hw_gpio = cs;
718			}
719
720			gpio_name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
721					"%s-CS%d", dev_name(&pdev->dev), cs);
722			if (!gpio_name) {
723				status = -ENOMEM;
724				goto out_rel_axi_clk;
725			}
726
727			cs_flags = of_property_read_bool(np, "spi-cs-high") ?
728				GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH;
729			status = devm_gpio_request_one(&pdev->dev, cs_gpio,
730					cs_flags, gpio_name);
731			if (status) {
732				dev_err(&pdev->dev,
733					"Can't request GPIO for CS %d\n", cs);
734				goto out_rel_axi_clk;
735			}
736		}
737
738		/*
739		 * Check if an address is configured for this SPI device. If
740		 * not, the MBus mapping via the 'ranges' property in the 'soc'
741		 * node is not configured and this device should not use the
742		 * direct mode. In this case, just continue with the next
743		 * device.
744		 */
745		status = of_address_to_resource(pdev->dev.of_node, cs + 1, r);
746		if (status)
747			continue;
748
749		/*
750		 * Only map one page for direct access. This is enough for the
751		 * simple TX transfer which only writes to the first word.
752		 * This needs to get extended for the direct SPI-NOR / SPI-NAND
753		 * support, once this gets implemented.
754		 */
755		dir_acc = &spi->child[cs].direct_access;
756		dir_acc->vaddr = devm_ioremap(&pdev->dev, r->start, PAGE_SIZE);
757		if (!dir_acc->vaddr) {
758			status = -ENOMEM;
759			goto out_rel_axi_clk;
760		}
761		dir_acc->size = PAGE_SIZE;
762
763		dev_info(&pdev->dev, "CS%d configured for direct access\n", cs);
764	}
765
766	pm_runtime_set_active(&pdev->dev);
767	pm_runtime_use_autosuspend(&pdev->dev);
768	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
769	pm_runtime_enable(&pdev->dev);
770
771	status = orion_spi_reset(spi);
772	if (status < 0)
773		goto out_rel_pm;
774
775	pm_runtime_mark_last_busy(&pdev->dev);
776	pm_runtime_put_autosuspend(&pdev->dev);
777
778	master->dev.of_node = pdev->dev.of_node;
779	status = spi_register_master(master);
780	if (status < 0)
781		goto out_rel_pm;
782
783	return status;
784
785out_rel_pm:
786	pm_runtime_disable(&pdev->dev);
787out_rel_axi_clk:
788	clk_disable_unprepare(spi->axi_clk);
789out_rel_clk:
790	clk_disable_unprepare(spi->clk);
791out:
792	spi_master_put(master);
793	return status;
794}
795
796
797static int orion_spi_remove(struct platform_device *pdev)
798{
799	struct spi_master *master = platform_get_drvdata(pdev);
800	struct orion_spi *spi = spi_master_get_devdata(master);
801
802	pm_runtime_get_sync(&pdev->dev);
803	clk_disable_unprepare(spi->axi_clk);
804	clk_disable_unprepare(spi->clk);
805
806	spi_unregister_master(master);
807	pm_runtime_disable(&pdev->dev);
808
809	return 0;
810}
811
812MODULE_ALIAS("platform:" DRIVER_NAME);
813
814#ifdef CONFIG_PM
815static int orion_spi_runtime_suspend(struct device *dev)
816{
817	struct spi_master *master = dev_get_drvdata(dev);
818	struct orion_spi *spi = spi_master_get_devdata(master);
819
820	clk_disable_unprepare(spi->axi_clk);
821	clk_disable_unprepare(spi->clk);
822	return 0;
823}
824
825static int orion_spi_runtime_resume(struct device *dev)
826{
827	struct spi_master *master = dev_get_drvdata(dev);
828	struct orion_spi *spi = spi_master_get_devdata(master);
829
830	if (!IS_ERR(spi->axi_clk))
831		clk_prepare_enable(spi->axi_clk);
832	return clk_prepare_enable(spi->clk);
833}
834#endif
835
836static const struct dev_pm_ops orion_spi_pm_ops = {
837	SET_RUNTIME_PM_OPS(orion_spi_runtime_suspend,
838			   orion_spi_runtime_resume,
839			   NULL)
840};
841
842static struct platform_driver orion_spi_driver = {
843	.driver = {
844		.name	= DRIVER_NAME,
845		.pm	= &orion_spi_pm_ops,
846		.of_match_table = of_match_ptr(orion_spi_of_match_table),
847	},
848	.probe		= orion_spi_probe,
849	.remove		= orion_spi_remove,
850};
851
852module_platform_driver(orion_spi_driver);
853
854MODULE_DESCRIPTION("Orion SPI driver");
855MODULE_AUTHOR("Shadi Ammouri <shadi@marvell.com>");
856MODULE_LICENSE("GPL");