xref: /linux/drivers/spi/spi-orion.c (revision d257f9bf06129613de539ea71ecea60848b662cd)
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_address.h>
22 #include <linux/of_device.h>
23 #include <linux/clk.h>
24 #include <linux/sizes.h>
25 #include <linux/gpio.h>
26 #include <asm/unaligned.h>
27 
28 #define DRIVER_NAME			"orion_spi"
29 
30 /* Runtime PM autosuspend timeout: PM is fairly light on this driver */
31 #define SPI_AUTOSUSPEND_TIMEOUT		200
32 
33 /* Some SoCs using this driver support up to 8 chip selects.
34  * It is up to the implementer to only use the chip selects
35  * that are available.
36  */
37 #define ORION_NUM_CHIPSELECTS		8
38 
39 #define ORION_SPI_WAIT_RDY_MAX_LOOP	2000 /* in usec */
40 
41 #define ORION_SPI_IF_CTRL_REG		0x00
42 #define ORION_SPI_IF_CONFIG_REG		0x04
43 #define ORION_SPI_IF_RXLSBF		BIT(14)
44 #define ORION_SPI_IF_TXLSBF		BIT(13)
45 #define ORION_SPI_DATA_OUT_REG		0x08
46 #define ORION_SPI_DATA_IN_REG		0x0c
47 #define ORION_SPI_INT_CAUSE_REG		0x10
48 #define ORION_SPI_TIMING_PARAMS_REG	0x18
49 
50 /* Register for the "Direct Mode" */
51 #define SPI_DIRECT_WRITE_CONFIG_REG	0x20
52 
53 #define ORION_SPI_TMISO_SAMPLE_MASK	(0x3 << 6)
54 #define ORION_SPI_TMISO_SAMPLE_1	(1 << 6)
55 #define ORION_SPI_TMISO_SAMPLE_2	(2 << 6)
56 
57 #define ORION_SPI_MODE_CPOL		(1 << 11)
58 #define ORION_SPI_MODE_CPHA		(1 << 12)
59 #define ORION_SPI_IF_8_16_BIT_MODE	(1 << 5)
60 #define ORION_SPI_CLK_PRESCALE_MASK	0x1F
61 #define ARMADA_SPI_CLK_PRESCALE_MASK	0xDF
62 #define ORION_SPI_MODE_MASK		(ORION_SPI_MODE_CPOL | \
63 					 ORION_SPI_MODE_CPHA)
64 #define ORION_SPI_CS_MASK	0x1C
65 #define ORION_SPI_CS_SHIFT	2
66 #define ORION_SPI_CS(cs)	((cs << ORION_SPI_CS_SHIFT) & \
67 					ORION_SPI_CS_MASK)
68 
69 enum orion_spi_type {
70 	ORION_SPI,
71 	ARMADA_SPI,
72 };
73 
74 struct orion_spi_dev {
75 	enum orion_spi_type	typ;
76 	/*
77 	 * min_divisor and max_hz should be exclusive, the only we can
78 	 * have both is for managing the armada-370-spi case with old
79 	 * device tree
80 	 */
81 	unsigned long		max_hz;
82 	unsigned int		min_divisor;
83 	unsigned int		max_divisor;
84 	u32			prescale_mask;
85 	bool			is_errata_50mhz_ac;
86 };
87 
88 struct orion_direct_acc {
89 	void __iomem		*vaddr;
90 	u32			size;
91 };
92 
93 struct orion_spi {
94 	struct spi_master	*master;
95 	void __iomem		*base;
96 	struct clk              *clk;
97 	const struct orion_spi_dev *devdata;
98 
99 	struct orion_direct_acc	direct_access[ORION_NUM_CHIPSELECTS];
100 };
101 
102 static inline void __iomem *spi_reg(struct orion_spi *orion_spi, u32 reg)
103 {
104 	return orion_spi->base + reg;
105 }
106 
107 static inline void
108 orion_spi_setbits(struct orion_spi *orion_spi, u32 reg, u32 mask)
109 {
110 	void __iomem *reg_addr = spi_reg(orion_spi, reg);
111 	u32 val;
112 
113 	val = readl(reg_addr);
114 	val |= mask;
115 	writel(val, reg_addr);
116 }
117 
118 static inline void
119 orion_spi_clrbits(struct orion_spi *orion_spi, u32 reg, u32 mask)
120 {
121 	void __iomem *reg_addr = spi_reg(orion_spi, reg);
122 	u32 val;
123 
124 	val = readl(reg_addr);
125 	val &= ~mask;
126 	writel(val, reg_addr);
127 }
128 
129 static int orion_spi_baudrate_set(struct spi_device *spi, unsigned int speed)
130 {
131 	u32 tclk_hz;
132 	u32 rate;
133 	u32 prescale;
134 	u32 reg;
135 	struct orion_spi *orion_spi;
136 	const struct orion_spi_dev *devdata;
137 
138 	orion_spi = spi_master_get_devdata(spi->master);
139 	devdata = orion_spi->devdata;
140 
141 	tclk_hz = clk_get_rate(orion_spi->clk);
142 
143 	if (devdata->typ == ARMADA_SPI) {
144 		/*
145 		 * Given the core_clk (tclk_hz) and the target rate (speed) we
146 		 * determine the best values for SPR (in [0 .. 15]) and SPPR (in
147 		 * [0..7]) such that
148 		 *
149 		 * 	core_clk / (SPR * 2 ** SPPR)
150 		 *
151 		 * is as big as possible but not bigger than speed.
152 		 */
153 
154 		/* best integer divider: */
155 		unsigned divider = DIV_ROUND_UP(tclk_hz, speed);
156 		unsigned spr, sppr;
157 
158 		if (divider < 16) {
159 			/* This is the easy case, divider is less than 16 */
160 			spr = divider;
161 			sppr = 0;
162 
163 		} else {
164 			unsigned two_pow_sppr;
165 			/*
166 			 * Find the highest bit set in divider. This and the
167 			 * three next bits define SPR (apart from rounding).
168 			 * SPPR is then the number of zero bits that must be
169 			 * appended:
170 			 */
171 			sppr = fls(divider) - 4;
172 
173 			/*
174 			 * As SPR only has 4 bits, we have to round divider up
175 			 * to the next multiple of 2 ** sppr.
176 			 */
177 			two_pow_sppr = 1 << sppr;
178 			divider = (divider + two_pow_sppr - 1) & -two_pow_sppr;
179 
180 			/*
181 			 * recalculate sppr as rounding up divider might have
182 			 * increased it enough to change the position of the
183 			 * highest set bit. In this case the bit that now
184 			 * doesn't make it into SPR is 0, so there is no need to
185 			 * round again.
186 			 */
187 			sppr = fls(divider) - 4;
188 			spr = divider >> sppr;
189 
190 			/*
191 			 * Now do range checking. SPR is constructed to have a
192 			 * width of 4 bits, so this is fine for sure. So we
193 			 * still need to check for sppr to fit into 3 bits:
194 			 */
195 			if (sppr > 7)
196 				return -EINVAL;
197 		}
198 
199 		prescale = ((sppr & 0x6) << 5) | ((sppr & 0x1) << 4) | spr;
200 	} else {
201 		/*
202 		 * the supported rates are: 4,6,8...30
203 		 * round up as we look for equal or less speed
204 		 */
205 		rate = DIV_ROUND_UP(tclk_hz, speed);
206 		rate = roundup(rate, 2);
207 
208 		/* check if requested speed is too small */
209 		if (rate > 30)
210 			return -EINVAL;
211 
212 		if (rate < 4)
213 			rate = 4;
214 
215 		/* Convert the rate to SPI clock divisor value.	*/
216 		prescale = 0x10 + rate/2;
217 	}
218 
219 	reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
220 	reg = ((reg & ~devdata->prescale_mask) | prescale);
221 	writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
222 
223 	return 0;
224 }
225 
226 static void
227 orion_spi_mode_set(struct spi_device *spi)
228 {
229 	u32 reg;
230 	struct orion_spi *orion_spi;
231 
232 	orion_spi = spi_master_get_devdata(spi->master);
233 
234 	reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
235 	reg &= ~ORION_SPI_MODE_MASK;
236 	if (spi->mode & SPI_CPOL)
237 		reg |= ORION_SPI_MODE_CPOL;
238 	if (spi->mode & SPI_CPHA)
239 		reg |= ORION_SPI_MODE_CPHA;
240 	if (spi->mode & SPI_LSB_FIRST)
241 		reg |= ORION_SPI_IF_RXLSBF | ORION_SPI_IF_TXLSBF;
242 	else
243 		reg &= ~(ORION_SPI_IF_RXLSBF | ORION_SPI_IF_TXLSBF);
244 
245 	writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
246 }
247 
248 static void
249 orion_spi_50mhz_ac_timing_erratum(struct spi_device *spi, unsigned int speed)
250 {
251 	u32 reg;
252 	struct orion_spi *orion_spi;
253 
254 	orion_spi = spi_master_get_devdata(spi->master);
255 
256 	/*
257 	 * Erratum description: (Erratum NO. FE-9144572) The device
258 	 * SPI interface supports frequencies of up to 50 MHz.
259 	 * However, due to this erratum, when the device core clock is
260 	 * 250 MHz and the SPI interfaces is configured for 50MHz SPI
261 	 * clock and CPOL=CPHA=1 there might occur data corruption on
262 	 * reads from the SPI device.
263 	 * Erratum Workaround:
264 	 * Work in one of the following configurations:
265 	 * 1. Set CPOL=CPHA=0 in "SPI Interface Configuration
266 	 * Register".
267 	 * 2. Set TMISO_SAMPLE value to 0x2 in "SPI Timing Parameters 1
268 	 * Register" before setting the interface.
269 	 */
270 	reg = readl(spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
271 	reg &= ~ORION_SPI_TMISO_SAMPLE_MASK;
272 
273 	if (clk_get_rate(orion_spi->clk) == 250000000 &&
274 			speed == 50000000 && spi->mode & SPI_CPOL &&
275 			spi->mode & SPI_CPHA)
276 		reg |= ORION_SPI_TMISO_SAMPLE_2;
277 	else
278 		reg |= ORION_SPI_TMISO_SAMPLE_1; /* This is the default value */
279 
280 	writel(reg, spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
281 }
282 
283 /*
284  * called only when no transfer is active on the bus
285  */
286 static int
287 orion_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
288 {
289 	struct orion_spi *orion_spi;
290 	unsigned int speed = spi->max_speed_hz;
291 	unsigned int bits_per_word = spi->bits_per_word;
292 	int	rc;
293 
294 	orion_spi = spi_master_get_devdata(spi->master);
295 
296 	if ((t != NULL) && t->speed_hz)
297 		speed = t->speed_hz;
298 
299 	if ((t != NULL) && t->bits_per_word)
300 		bits_per_word = t->bits_per_word;
301 
302 	orion_spi_mode_set(spi);
303 
304 	if (orion_spi->devdata->is_errata_50mhz_ac)
305 		orion_spi_50mhz_ac_timing_erratum(spi, speed);
306 
307 	rc = orion_spi_baudrate_set(spi, speed);
308 	if (rc)
309 		return rc;
310 
311 	if (bits_per_word == 16)
312 		orion_spi_setbits(orion_spi, ORION_SPI_IF_CONFIG_REG,
313 				  ORION_SPI_IF_8_16_BIT_MODE);
314 	else
315 		orion_spi_clrbits(orion_spi, ORION_SPI_IF_CONFIG_REG,
316 				  ORION_SPI_IF_8_16_BIT_MODE);
317 
318 	return 0;
319 }
320 
321 static void orion_spi_set_cs(struct spi_device *spi, bool enable)
322 {
323 	struct orion_spi *orion_spi;
324 	int cs;
325 
326 	if (gpio_is_valid(spi->cs_gpio))
327 		cs = 0;
328 	else
329 		cs = spi->chip_select;
330 
331 	orion_spi = spi_master_get_devdata(spi->master);
332 
333 	orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, ORION_SPI_CS_MASK);
334 	orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG,
335 				ORION_SPI_CS(cs));
336 
337 	/* Chip select logic is inverted from spi_set_cs */
338 	if (!enable)
339 		orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
340 	else
341 		orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
342 }
343 
344 static inline int orion_spi_wait_till_ready(struct orion_spi *orion_spi)
345 {
346 	int i;
347 
348 	for (i = 0; i < ORION_SPI_WAIT_RDY_MAX_LOOP; i++) {
349 		if (readl(spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG)))
350 			return 1;
351 
352 		udelay(1);
353 	}
354 
355 	return -1;
356 }
357 
358 static inline int
359 orion_spi_write_read_8bit(struct spi_device *spi,
360 			  const u8 **tx_buf, u8 **rx_buf)
361 {
362 	void __iomem *tx_reg, *rx_reg, *int_reg;
363 	struct orion_spi *orion_spi;
364 
365 	orion_spi = spi_master_get_devdata(spi->master);
366 	tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG);
367 	rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG);
368 	int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG);
369 
370 	/* clear the interrupt cause register */
371 	writel(0x0, int_reg);
372 
373 	if (tx_buf && *tx_buf)
374 		writel(*(*tx_buf)++, tx_reg);
375 	else
376 		writel(0, tx_reg);
377 
378 	if (orion_spi_wait_till_ready(orion_spi) < 0) {
379 		dev_err(&spi->dev, "TXS timed out\n");
380 		return -1;
381 	}
382 
383 	if (rx_buf && *rx_buf)
384 		*(*rx_buf)++ = readl(rx_reg);
385 
386 	return 1;
387 }
388 
389 static inline int
390 orion_spi_write_read_16bit(struct spi_device *spi,
391 			   const u16 **tx_buf, u16 **rx_buf)
392 {
393 	void __iomem *tx_reg, *rx_reg, *int_reg;
394 	struct orion_spi *orion_spi;
395 
396 	orion_spi = spi_master_get_devdata(spi->master);
397 	tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG);
398 	rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG);
399 	int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG);
400 
401 	/* clear the interrupt cause register */
402 	writel(0x0, int_reg);
403 
404 	if (tx_buf && *tx_buf)
405 		writel(__cpu_to_le16(get_unaligned((*tx_buf)++)), tx_reg);
406 	else
407 		writel(0, tx_reg);
408 
409 	if (orion_spi_wait_till_ready(orion_spi) < 0) {
410 		dev_err(&spi->dev, "TXS timed out\n");
411 		return -1;
412 	}
413 
414 	if (rx_buf && *rx_buf)
415 		put_unaligned(__le16_to_cpu(readl(rx_reg)), (*rx_buf)++);
416 
417 	return 1;
418 }
419 
420 static unsigned int
421 orion_spi_write_read(struct spi_device *spi, struct spi_transfer *xfer)
422 {
423 	unsigned int count;
424 	int word_len;
425 	struct orion_spi *orion_spi;
426 	int cs = spi->chip_select;
427 
428 	word_len = spi->bits_per_word;
429 	count = xfer->len;
430 
431 	orion_spi = spi_master_get_devdata(spi->master);
432 
433 	/*
434 	 * Use SPI direct write mode if base address is available. Otherwise
435 	 * fall back to PIO mode for this transfer.
436 	 */
437 	if ((orion_spi->direct_access[cs].vaddr) && (xfer->tx_buf) &&
438 	    (word_len == 8)) {
439 		unsigned int cnt = count / 4;
440 		unsigned int rem = count % 4;
441 
442 		/*
443 		 * Send the TX-data to the SPI device via the direct
444 		 * mapped address window
445 		 */
446 		iowrite32_rep(orion_spi->direct_access[cs].vaddr,
447 			      xfer->tx_buf, cnt);
448 		if (rem) {
449 			u32 *buf = (u32 *)xfer->tx_buf;
450 
451 			iowrite8_rep(orion_spi->direct_access[cs].vaddr,
452 				     &buf[cnt], rem);
453 		}
454 
455 		return count;
456 	}
457 
458 	if (word_len == 8) {
459 		const u8 *tx = xfer->tx_buf;
460 		u8 *rx = xfer->rx_buf;
461 
462 		do {
463 			if (orion_spi_write_read_8bit(spi, &tx, &rx) < 0)
464 				goto out;
465 			count--;
466 		} while (count);
467 	} else if (word_len == 16) {
468 		const u16 *tx = xfer->tx_buf;
469 		u16 *rx = xfer->rx_buf;
470 
471 		do {
472 			if (orion_spi_write_read_16bit(spi, &tx, &rx) < 0)
473 				goto out;
474 			count -= 2;
475 		} while (count);
476 	}
477 
478 out:
479 	return xfer->len - count;
480 }
481 
482 static int orion_spi_transfer_one(struct spi_master *master,
483 					struct spi_device *spi,
484 					struct spi_transfer *t)
485 {
486 	int status = 0;
487 
488 	status = orion_spi_setup_transfer(spi, t);
489 	if (status < 0)
490 		return status;
491 
492 	if (t->len)
493 		orion_spi_write_read(spi, t);
494 
495 	return status;
496 }
497 
498 static int orion_spi_setup(struct spi_device *spi)
499 {
500 	return orion_spi_setup_transfer(spi, NULL);
501 }
502 
503 static int orion_spi_reset(struct orion_spi *orion_spi)
504 {
505 	/* Verify that the CS is deasserted */
506 	orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
507 
508 	/* Don't deassert CS between the direct mapped SPI transfers */
509 	writel(0, spi_reg(orion_spi, SPI_DIRECT_WRITE_CONFIG_REG));
510 
511 	return 0;
512 }
513 
514 static const struct orion_spi_dev orion_spi_dev_data = {
515 	.typ = ORION_SPI,
516 	.min_divisor = 4,
517 	.max_divisor = 30,
518 	.prescale_mask = ORION_SPI_CLK_PRESCALE_MASK,
519 };
520 
521 static const struct orion_spi_dev armada_370_spi_dev_data = {
522 	.typ = ARMADA_SPI,
523 	.min_divisor = 4,
524 	.max_divisor = 1920,
525 	.max_hz = 50000000,
526 	.prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
527 };
528 
529 static const struct orion_spi_dev armada_xp_spi_dev_data = {
530 	.typ = ARMADA_SPI,
531 	.max_hz = 50000000,
532 	.max_divisor = 1920,
533 	.prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
534 };
535 
536 static const struct orion_spi_dev armada_375_spi_dev_data = {
537 	.typ = ARMADA_SPI,
538 	.min_divisor = 15,
539 	.max_divisor = 1920,
540 	.prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
541 };
542 
543 static const struct orion_spi_dev armada_380_spi_dev_data = {
544 	.typ = ARMADA_SPI,
545 	.max_hz = 50000000,
546 	.max_divisor = 1920,
547 	.prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
548 	.is_errata_50mhz_ac = true,
549 };
550 
551 static const struct of_device_id orion_spi_of_match_table[] = {
552 	{
553 		.compatible = "marvell,orion-spi",
554 		.data = &orion_spi_dev_data,
555 	},
556 	{
557 		.compatible = "marvell,armada-370-spi",
558 		.data = &armada_370_spi_dev_data,
559 	},
560 	{
561 		.compatible = "marvell,armada-375-spi",
562 		.data = &armada_375_spi_dev_data,
563 	},
564 	{
565 		.compatible = "marvell,armada-380-spi",
566 		.data = &armada_380_spi_dev_data,
567 	},
568 	{
569 		.compatible = "marvell,armada-390-spi",
570 		.data = &armada_xp_spi_dev_data,
571 	},
572 	{
573 		.compatible = "marvell,armada-xp-spi",
574 		.data = &armada_xp_spi_dev_data,
575 	},
576 
577 	{}
578 };
579 MODULE_DEVICE_TABLE(of, orion_spi_of_match_table);
580 
581 static int orion_spi_probe(struct platform_device *pdev)
582 {
583 	const struct of_device_id *of_id;
584 	const struct orion_spi_dev *devdata;
585 	struct spi_master *master;
586 	struct orion_spi *spi;
587 	struct resource *r;
588 	unsigned long tclk_hz;
589 	int status = 0;
590 	struct device_node *np;
591 
592 	master = spi_alloc_master(&pdev->dev, sizeof(*spi));
593 	if (master == NULL) {
594 		dev_dbg(&pdev->dev, "master allocation failed\n");
595 		return -ENOMEM;
596 	}
597 
598 	if (pdev->id != -1)
599 		master->bus_num = pdev->id;
600 	if (pdev->dev.of_node) {
601 		u32 cell_index;
602 
603 		if (!of_property_read_u32(pdev->dev.of_node, "cell-index",
604 					  &cell_index))
605 			master->bus_num = cell_index;
606 	}
607 
608 	/* we support all 4 SPI modes and LSB first option */
609 	master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_LSB_FIRST;
610 	master->set_cs = orion_spi_set_cs;
611 	master->transfer_one = orion_spi_transfer_one;
612 	master->num_chipselect = ORION_NUM_CHIPSELECTS;
613 	master->setup = orion_spi_setup;
614 	master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
615 	master->auto_runtime_pm = true;
616 	master->flags = SPI_MASTER_GPIO_SS;
617 
618 	platform_set_drvdata(pdev, master);
619 
620 	spi = spi_master_get_devdata(master);
621 	spi->master = master;
622 
623 	of_id = of_match_device(orion_spi_of_match_table, &pdev->dev);
624 	devdata = (of_id) ? of_id->data : &orion_spi_dev_data;
625 	spi->devdata = devdata;
626 
627 	spi->clk = devm_clk_get(&pdev->dev, NULL);
628 	if (IS_ERR(spi->clk)) {
629 		status = PTR_ERR(spi->clk);
630 		goto out;
631 	}
632 
633 	status = clk_prepare_enable(spi->clk);
634 	if (status)
635 		goto out;
636 
637 	tclk_hz = clk_get_rate(spi->clk);
638 
639 	/*
640 	 * With old device tree, armada-370-spi could be used with
641 	 * Armada XP, however for this SoC the maximum frequency is
642 	 * 50MHz instead of tclk/4. On Armada 370, tclk cannot be
643 	 * higher than 200MHz. So, in order to be able to handle both
644 	 * SoCs, we can take the minimum of 50MHz and tclk/4.
645 	 */
646 	if (of_device_is_compatible(pdev->dev.of_node,
647 					"marvell,armada-370-spi"))
648 		master->max_speed_hz = min(devdata->max_hz,
649 				DIV_ROUND_UP(tclk_hz, devdata->min_divisor));
650 	else if (devdata->min_divisor)
651 		master->max_speed_hz =
652 			DIV_ROUND_UP(tclk_hz, devdata->min_divisor);
653 	else
654 		master->max_speed_hz = devdata->max_hz;
655 	master->min_speed_hz = DIV_ROUND_UP(tclk_hz, devdata->max_divisor);
656 
657 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
658 	spi->base = devm_ioremap_resource(&pdev->dev, r);
659 	if (IS_ERR(spi->base)) {
660 		status = PTR_ERR(spi->base);
661 		goto out_rel_clk;
662 	}
663 
664 	/* Scan all SPI devices of this controller for direct mapped devices */
665 	for_each_available_child_of_node(pdev->dev.of_node, np) {
666 		u32 cs;
667 
668 		/* Get chip-select number from the "reg" property */
669 		status = of_property_read_u32(np, "reg", &cs);
670 		if (status) {
671 			dev_err(&pdev->dev,
672 				"%s has no valid 'reg' property (%d)\n",
673 				np->full_name, status);
674 			status = 0;
675 			continue;
676 		}
677 
678 		/*
679 		 * Check if an address is configured for this SPI device. If
680 		 * not, the MBus mapping via the 'ranges' property in the 'soc'
681 		 * node is not configured and this device should not use the
682 		 * direct mode. In this case, just continue with the next
683 		 * device.
684 		 */
685 		status = of_address_to_resource(pdev->dev.of_node, cs + 1, r);
686 		if (status)
687 			continue;
688 
689 		/*
690 		 * Only map one page for direct access. This is enough for the
691 		 * simple TX transfer which only writes to the first word.
692 		 * This needs to get extended for the direct SPI-NOR / SPI-NAND
693 		 * support, once this gets implemented.
694 		 */
695 		spi->direct_access[cs].vaddr = devm_ioremap(&pdev->dev,
696 							    r->start,
697 							    PAGE_SIZE);
698 		if (!spi->direct_access[cs].vaddr) {
699 			status = -ENOMEM;
700 			goto out_rel_clk;
701 		}
702 		spi->direct_access[cs].size = PAGE_SIZE;
703 
704 		dev_info(&pdev->dev, "CS%d configured for direct access\n", cs);
705 	}
706 
707 	pm_runtime_set_active(&pdev->dev);
708 	pm_runtime_use_autosuspend(&pdev->dev);
709 	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
710 	pm_runtime_enable(&pdev->dev);
711 
712 	status = orion_spi_reset(spi);
713 	if (status < 0)
714 		goto out_rel_pm;
715 
716 	pm_runtime_mark_last_busy(&pdev->dev);
717 	pm_runtime_put_autosuspend(&pdev->dev);
718 
719 	master->dev.of_node = pdev->dev.of_node;
720 	status = spi_register_master(master);
721 	if (status < 0)
722 		goto out_rel_pm;
723 
724 	return status;
725 
726 out_rel_pm:
727 	pm_runtime_disable(&pdev->dev);
728 out_rel_clk:
729 	clk_disable_unprepare(spi->clk);
730 out:
731 	spi_master_put(master);
732 	return status;
733 }
734 
735 
736 static int orion_spi_remove(struct platform_device *pdev)
737 {
738 	struct spi_master *master = platform_get_drvdata(pdev);
739 	struct orion_spi *spi = spi_master_get_devdata(master);
740 
741 	pm_runtime_get_sync(&pdev->dev);
742 	clk_disable_unprepare(spi->clk);
743 
744 	spi_unregister_master(master);
745 	pm_runtime_disable(&pdev->dev);
746 
747 	return 0;
748 }
749 
750 MODULE_ALIAS("platform:" DRIVER_NAME);
751 
752 #ifdef CONFIG_PM
753 static int orion_spi_runtime_suspend(struct device *dev)
754 {
755 	struct spi_master *master = dev_get_drvdata(dev);
756 	struct orion_spi *spi = spi_master_get_devdata(master);
757 
758 	clk_disable_unprepare(spi->clk);
759 	return 0;
760 }
761 
762 static int orion_spi_runtime_resume(struct device *dev)
763 {
764 	struct spi_master *master = dev_get_drvdata(dev);
765 	struct orion_spi *spi = spi_master_get_devdata(master);
766 
767 	return clk_prepare_enable(spi->clk);
768 }
769 #endif
770 
771 static const struct dev_pm_ops orion_spi_pm_ops = {
772 	SET_RUNTIME_PM_OPS(orion_spi_runtime_suspend,
773 			   orion_spi_runtime_resume,
774 			   NULL)
775 };
776 
777 static struct platform_driver orion_spi_driver = {
778 	.driver = {
779 		.name	= DRIVER_NAME,
780 		.pm	= &orion_spi_pm_ops,
781 		.of_match_table = of_match_ptr(orion_spi_of_match_table),
782 	},
783 	.probe		= orion_spi_probe,
784 	.remove		= orion_spi_remove,
785 };
786 
787 module_platform_driver(orion_spi_driver);
788 
789 MODULE_DESCRIPTION("Orion SPI driver");
790 MODULE_AUTHOR("Shadi Ammouri <shadi@marvell.com>");
791 MODULE_LICENSE("GPL");
792