xref: /openbmc/u-boot/drivers/spi/omap3_spi.c (revision d374e90b)
1 /*
2  * Copyright (C) 2016 Jagan Teki <jteki@openedev.com>
3  *		      Christophe Ricard <christophe.ricard@gmail.com>
4  *
5  * Copyright (C) 2010 Dirk Behme <dirk.behme@googlemail.com>
6  *
7  * Driver for McSPI controller on OMAP3. Based on davinci_spi.c
8  * Copyright (C) 2009 Texas Instruments Incorporated - http://www.ti.com/
9  *
10  * Copyright (C) 2007 Atmel Corporation
11  *
12  * Parts taken from linux/drivers/spi/omap2_mcspi.c
13  * Copyright (C) 2005, 2006 Nokia Corporation
14  *
15  * Modified by Ruslan Araslanov <ruslan.araslanov@vitecmm.com>
16  *
17  * SPDX-License-Identifier:	GPL-2.0+
18  */
19 
20 #include <common.h>
21 #include <dm.h>
22 #include <spi.h>
23 #include <malloc.h>
24 #include <asm/io.h>
25 
26 DECLARE_GLOBAL_DATA_PTR;
27 
28 #if defined(CONFIG_AM33XX) || defined(CONFIG_AM43XX)
29 #define OMAP3_MCSPI1_BASE	0x48030100
30 #define OMAP3_MCSPI2_BASE	0x481A0100
31 #else
32 #define OMAP3_MCSPI1_BASE	0x48098000
33 #define OMAP3_MCSPI2_BASE	0x4809A000
34 #define OMAP3_MCSPI3_BASE	0x480B8000
35 #define OMAP3_MCSPI4_BASE	0x480BA000
36 #endif
37 
38 #define OMAP4_MCSPI_REG_OFFSET	0x100
39 
40 struct omap2_mcspi_platform_config {
41 	unsigned int regs_offset;
42 };
43 
44 /* per-register bitmasks */
45 #define OMAP3_MCSPI_SYSCONFIG_SMARTIDLE (2 << 3)
46 #define OMAP3_MCSPI_SYSCONFIG_ENAWAKEUP BIT(2)
47 #define OMAP3_MCSPI_SYSCONFIG_AUTOIDLE	BIT(0)
48 #define OMAP3_MCSPI_SYSCONFIG_SOFTRESET BIT(1)
49 
50 #define OMAP3_MCSPI_SYSSTATUS_RESETDONE BIT(0)
51 
52 #define OMAP3_MCSPI_MODULCTRL_SINGLE	BIT(0)
53 #define OMAP3_MCSPI_MODULCTRL_MS	BIT(2)
54 #define OMAP3_MCSPI_MODULCTRL_STEST	BIT(3)
55 
56 #define OMAP3_MCSPI_CHCONF_PHA		BIT(0)
57 #define OMAP3_MCSPI_CHCONF_POL		BIT(1)
58 #define OMAP3_MCSPI_CHCONF_CLKD_MASK	GENMASK(5, 2)
59 #define OMAP3_MCSPI_CHCONF_EPOL		BIT(6)
60 #define OMAP3_MCSPI_CHCONF_WL_MASK	GENMASK(11, 7)
61 #define OMAP3_MCSPI_CHCONF_TRM_RX_ONLY	BIT(12)
62 #define OMAP3_MCSPI_CHCONF_TRM_TX_ONLY	BIT(13)
63 #define OMAP3_MCSPI_CHCONF_TRM_MASK	GENMASK(13, 12)
64 #define OMAP3_MCSPI_CHCONF_DMAW		BIT(14)
65 #define OMAP3_MCSPI_CHCONF_DMAR		BIT(15)
66 #define OMAP3_MCSPI_CHCONF_DPE0		BIT(16)
67 #define OMAP3_MCSPI_CHCONF_DPE1		BIT(17)
68 #define OMAP3_MCSPI_CHCONF_IS		BIT(18)
69 #define OMAP3_MCSPI_CHCONF_TURBO	BIT(19)
70 #define OMAP3_MCSPI_CHCONF_FORCE	BIT(20)
71 
72 #define OMAP3_MCSPI_CHSTAT_RXS		BIT(0)
73 #define OMAP3_MCSPI_CHSTAT_TXS		BIT(1)
74 #define OMAP3_MCSPI_CHSTAT_EOT		BIT(2)
75 
76 #define OMAP3_MCSPI_CHCTRL_EN		BIT(0)
77 #define OMAP3_MCSPI_CHCTRL_DIS		(0 << 0)
78 
79 #define OMAP3_MCSPI_WAKEUPENABLE_WKEN	BIT(0)
80 #define MCSPI_PINDIR_D0_IN_D1_OUT	0
81 #define MCSPI_PINDIR_D0_OUT_D1_IN	1
82 
83 #define OMAP3_MCSPI_MAX_FREQ		48000000
84 #define SPI_WAIT_TIMEOUT		10
85 
86 /* OMAP3 McSPI registers */
87 struct mcspi_channel {
88 	unsigned int chconf;		/* 0x2C, 0x40, 0x54, 0x68 */
89 	unsigned int chstat;		/* 0x30, 0x44, 0x58, 0x6C */
90 	unsigned int chctrl;		/* 0x34, 0x48, 0x5C, 0x70 */
91 	unsigned int tx;		/* 0x38, 0x4C, 0x60, 0x74 */
92 	unsigned int rx;		/* 0x3C, 0x50, 0x64, 0x78 */
93 };
94 
95 struct mcspi {
96 	unsigned char res1[0x10];
97 	unsigned int sysconfig;		/* 0x10 */
98 	unsigned int sysstatus;		/* 0x14 */
99 	unsigned int irqstatus;		/* 0x18 */
100 	unsigned int irqenable;		/* 0x1C */
101 	unsigned int wakeupenable;	/* 0x20 */
102 	unsigned int syst;		/* 0x24 */
103 	unsigned int modulctrl;		/* 0x28 */
104 	struct mcspi_channel channel[4];
105 	/* channel0: 0x2C - 0x3C, bus 0 & 1 & 2 & 3 */
106 	/* channel1: 0x40 - 0x50, bus 0 & 1 */
107 	/* channel2: 0x54 - 0x64, bus 0 & 1 */
108 	/* channel3: 0x68 - 0x78, bus 0 */
109 };
110 
111 struct omap3_spi_priv {
112 #ifndef CONFIG_DM_SPI
113 	struct spi_slave slave;
114 #endif
115 	struct mcspi *regs;
116 	unsigned int cs;
117 	unsigned int freq;
118 	unsigned int mode;
119 	unsigned int wordlen;
120 	unsigned int pin_dir:1;
121 };
122 
123 static void omap3_spi_write_chconf(struct omap3_spi_priv *priv, int val)
124 {
125 	writel(val, &priv->regs->channel[priv->cs].chconf);
126 	/* Flash post writes to make immediate effect */
127 	readl(&priv->regs->channel[priv->cs].chconf);
128 }
129 
130 static void omap3_spi_set_enable(struct omap3_spi_priv *priv, int enable)
131 {
132 	writel(enable, &priv->regs->channel[priv->cs].chctrl);
133 	/* Flash post writes to make immediate effect */
134 	readl(&priv->regs->channel[priv->cs].chctrl);
135 }
136 
137 static int omap3_spi_write(struct omap3_spi_priv *priv, unsigned int len,
138 			   const void *txp, unsigned long flags)
139 {
140 	ulong start;
141 	int i, chconf;
142 
143 	chconf = readl(&priv->regs->channel[priv->cs].chconf);
144 
145 	/* Enable the channel */
146 	omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_EN);
147 
148 	chconf &= ~(OMAP3_MCSPI_CHCONF_TRM_MASK | OMAP3_MCSPI_CHCONF_WL_MASK);
149 	chconf |= (priv->wordlen - 1) << 7;
150 	chconf |= OMAP3_MCSPI_CHCONF_TRM_TX_ONLY;
151 	chconf |= OMAP3_MCSPI_CHCONF_FORCE;
152 	omap3_spi_write_chconf(priv, chconf);
153 
154 	for (i = 0; i < len; i++) {
155 		/* wait till TX register is empty (TXS == 1) */
156 		start = get_timer(0);
157 		while (!(readl(&priv->regs->channel[priv->cs].chstat) &
158 			 OMAP3_MCSPI_CHSTAT_TXS)) {
159 			if (get_timer(start) > SPI_WAIT_TIMEOUT) {
160 				printf("SPI TXS timed out, status=0x%08x\n",
161 					readl(&priv->regs->channel[priv->cs].chstat));
162 				return -1;
163 			}
164 		}
165 		/* Write the data */
166 		unsigned int *tx = &priv->regs->channel[priv->cs].tx;
167 		if (priv->wordlen > 16)
168 			writel(((u32 *)txp)[i], tx);
169 		else if (priv->wordlen > 8)
170 			writel(((u16 *)txp)[i], tx);
171 		else
172 			writel(((u8 *)txp)[i], tx);
173 	}
174 
175 	/* wait to finish of transfer */
176 	while ((readl(&priv->regs->channel[priv->cs].chstat) &
177 			(OMAP3_MCSPI_CHSTAT_EOT | OMAP3_MCSPI_CHSTAT_TXS)) !=
178 			(OMAP3_MCSPI_CHSTAT_EOT | OMAP3_MCSPI_CHSTAT_TXS))
179 		;
180 
181 	/* Disable the channel otherwise the next immediate RX will get affected */
182 	omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_DIS);
183 
184 	if (flags & SPI_XFER_END) {
185 
186 		chconf &= ~OMAP3_MCSPI_CHCONF_FORCE;
187 		omap3_spi_write_chconf(priv, chconf);
188 	}
189 	return 0;
190 }
191 
192 static int omap3_spi_read(struct omap3_spi_priv *priv, unsigned int len,
193 			  void *rxp, unsigned long flags)
194 {
195 	int i, chconf;
196 	ulong start;
197 
198 	chconf = readl(&priv->regs->channel[priv->cs].chconf);
199 
200 	/* Enable the channel */
201 	omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_EN);
202 
203 	chconf &= ~(OMAP3_MCSPI_CHCONF_TRM_MASK | OMAP3_MCSPI_CHCONF_WL_MASK);
204 	chconf |= (priv->wordlen - 1) << 7;
205 	chconf |= OMAP3_MCSPI_CHCONF_TRM_RX_ONLY;
206 	chconf |= OMAP3_MCSPI_CHCONF_FORCE;
207 	omap3_spi_write_chconf(priv, chconf);
208 
209 	writel(0, &priv->regs->channel[priv->cs].tx);
210 
211 	for (i = 0; i < len; i++) {
212 		start = get_timer(0);
213 		/* Wait till RX register contains data (RXS == 1) */
214 		while (!(readl(&priv->regs->channel[priv->cs].chstat) &
215 			 OMAP3_MCSPI_CHSTAT_RXS)) {
216 			if (get_timer(start) > SPI_WAIT_TIMEOUT) {
217 				printf("SPI RXS timed out, status=0x%08x\n",
218 					readl(&priv->regs->channel[priv->cs].chstat));
219 				return -1;
220 			}
221 		}
222 
223 		/* Disable the channel to prevent furher receiving */
224 		if (i == (len - 1))
225 			omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_DIS);
226 
227 		/* Read the data */
228 		unsigned int *rx = &priv->regs->channel[priv->cs].rx;
229 		if (priv->wordlen > 16)
230 			((u32 *)rxp)[i] = readl(rx);
231 		else if (priv->wordlen > 8)
232 			((u16 *)rxp)[i] = (u16)readl(rx);
233 		else
234 			((u8 *)rxp)[i] = (u8)readl(rx);
235 	}
236 
237 	if (flags & SPI_XFER_END) {
238 		chconf &= ~OMAP3_MCSPI_CHCONF_FORCE;
239 		omap3_spi_write_chconf(priv, chconf);
240 	}
241 
242 	return 0;
243 }
244 
245 /*McSPI Transmit Receive Mode*/
246 static int omap3_spi_txrx(struct omap3_spi_priv *priv, unsigned int len,
247 			  const void *txp, void *rxp, unsigned long flags)
248 {
249 	ulong start;
250 	int chconf, i = 0;
251 
252 	chconf = readl(&priv->regs->channel[priv->cs].chconf);
253 
254 	/*Enable SPI channel*/
255 	omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_EN);
256 
257 	/*set TRANSMIT-RECEIVE Mode*/
258 	chconf &= ~(OMAP3_MCSPI_CHCONF_TRM_MASK | OMAP3_MCSPI_CHCONF_WL_MASK);
259 	chconf |= (priv->wordlen - 1) << 7;
260 	chconf |= OMAP3_MCSPI_CHCONF_FORCE;
261 	omap3_spi_write_chconf(priv, chconf);
262 
263 	/*Shift in and out 1 byte at time*/
264 	for (i=0; i < len; i++){
265 		/* Write: wait for TX empty (TXS == 1)*/
266 		start = get_timer(0);
267 		while (!(readl(&priv->regs->channel[priv->cs].chstat) &
268 			 OMAP3_MCSPI_CHSTAT_TXS)) {
269 			if (get_timer(start) > SPI_WAIT_TIMEOUT) {
270 				printf("SPI TXS timed out, status=0x%08x\n",
271 					readl(&priv->regs->channel[priv->cs].chstat));
272 				return -1;
273 			}
274 		}
275 		/* Write the data */
276 		unsigned int *tx = &priv->regs->channel[priv->cs].tx;
277 		if (priv->wordlen > 16)
278 			writel(((u32 *)txp)[i], tx);
279 		else if (priv->wordlen > 8)
280 			writel(((u16 *)txp)[i], tx);
281 		else
282 			writel(((u8 *)txp)[i], tx);
283 
284 		/*Read: wait for RX containing data (RXS == 1)*/
285 		start = get_timer(0);
286 		while (!(readl(&priv->regs->channel[priv->cs].chstat) &
287 			 OMAP3_MCSPI_CHSTAT_RXS)) {
288 			if (get_timer(start) > SPI_WAIT_TIMEOUT) {
289 				printf("SPI RXS timed out, status=0x%08x\n",
290 					readl(&priv->regs->channel[priv->cs].chstat));
291 				return -1;
292 			}
293 		}
294 		/* Read the data */
295 		unsigned int *rx = &priv->regs->channel[priv->cs].rx;
296 		if (priv->wordlen > 16)
297 			((u32 *)rxp)[i] = readl(rx);
298 		else if (priv->wordlen > 8)
299 			((u16 *)rxp)[i] = (u16)readl(rx);
300 		else
301 			((u8 *)rxp)[i] = (u8)readl(rx);
302 	}
303 	/* Disable the channel */
304 	omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_DIS);
305 
306 	/*if transfer must be terminated disable the channel*/
307 	if (flags & SPI_XFER_END) {
308 		chconf &= ~OMAP3_MCSPI_CHCONF_FORCE;
309 		omap3_spi_write_chconf(priv, chconf);
310 	}
311 
312 	return 0;
313 }
314 
315 static int _spi_xfer(struct omap3_spi_priv *priv, unsigned int bitlen,
316 		     const void *dout, void *din, unsigned long flags)
317 {
318 	unsigned int	len;
319 	int ret = -1;
320 
321 	if (priv->wordlen < 4 || priv->wordlen > 32) {
322 		printf("omap3_spi: invalid wordlen %d\n", priv->wordlen);
323 		return -1;
324 	}
325 
326 	if (bitlen % priv->wordlen)
327 		return -1;
328 
329 	len = bitlen / priv->wordlen;
330 
331 	if (bitlen == 0) {	 /* only change CS */
332 		int chconf = readl(&priv->regs->channel[priv->cs].chconf);
333 
334 		if (flags & SPI_XFER_BEGIN) {
335 			omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_EN);
336 			chconf |= OMAP3_MCSPI_CHCONF_FORCE;
337 			omap3_spi_write_chconf(priv, chconf);
338 		}
339 		if (flags & SPI_XFER_END) {
340 			chconf &= ~OMAP3_MCSPI_CHCONF_FORCE;
341 			omap3_spi_write_chconf(priv, chconf);
342 			omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_DIS);
343 		}
344 		ret = 0;
345 	} else {
346 		if (dout != NULL && din != NULL)
347 			ret = omap3_spi_txrx(priv, len, dout, din, flags);
348 		else if (dout != NULL)
349 			ret = omap3_spi_write(priv, len, dout, flags);
350 		else if (din != NULL)
351 			ret = omap3_spi_read(priv, len, din, flags);
352 	}
353 	return ret;
354 }
355 
356 static void _omap3_spi_set_speed(struct omap3_spi_priv *priv)
357 {
358 	uint32_t confr, div = 0;
359 
360 	confr = readl(&priv->regs->channel[priv->cs].chconf);
361 
362 	/* Calculate clock divisor. Valid range: 0x0 - 0xC ( /1 - /4096 ) */
363 	if (priv->freq) {
364 		while (div <= 0xC && (OMAP3_MCSPI_MAX_FREQ / (1 << div))
365 					> priv->freq)
366 			div++;
367 	} else {
368 		 div = 0xC;
369 	}
370 
371 	/* set clock divisor */
372 	confr &= ~OMAP3_MCSPI_CHCONF_CLKD_MASK;
373 	confr |= div << 2;
374 
375 	omap3_spi_write_chconf(priv, confr);
376 }
377 
378 static void _omap3_spi_set_mode(struct omap3_spi_priv *priv)
379 {
380 	uint32_t confr;
381 
382 	confr = readl(&priv->regs->channel[priv->cs].chconf);
383 
384 	/* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
385 	 * REVISIT: this controller could support SPI_3WIRE mode.
386 	 */
387 	if (priv->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
388 		confr &= ~(OMAP3_MCSPI_CHCONF_IS|OMAP3_MCSPI_CHCONF_DPE1);
389 		confr |= OMAP3_MCSPI_CHCONF_DPE0;
390 	} else {
391 		confr &= ~OMAP3_MCSPI_CHCONF_DPE0;
392 		confr |= OMAP3_MCSPI_CHCONF_IS|OMAP3_MCSPI_CHCONF_DPE1;
393 	}
394 
395 	/* set SPI mode 0..3 */
396 	confr &= ~(OMAP3_MCSPI_CHCONF_POL | OMAP3_MCSPI_CHCONF_PHA);
397 	if (priv->mode & SPI_CPHA)
398 		confr |= OMAP3_MCSPI_CHCONF_PHA;
399 	if (priv->mode & SPI_CPOL)
400 		confr |= OMAP3_MCSPI_CHCONF_POL;
401 
402 	/* set chipselect polarity; manage with FORCE */
403 	if (!(priv->mode & SPI_CS_HIGH))
404 		confr |= OMAP3_MCSPI_CHCONF_EPOL; /* active-low; normal */
405 	else
406 		confr &= ~OMAP3_MCSPI_CHCONF_EPOL;
407 
408 	/* Transmit & receive mode */
409 	confr &= ~OMAP3_MCSPI_CHCONF_TRM_MASK;
410 
411 	omap3_spi_write_chconf(priv, confr);
412 }
413 
414 static void _omap3_spi_set_wordlen(struct omap3_spi_priv *priv)
415 {
416 	unsigned int confr;
417 
418 	/* McSPI individual channel configuration */
419 	confr = readl(&priv->regs->channel[priv->wordlen].chconf);
420 
421 	/* wordlength */
422 	confr &= ~OMAP3_MCSPI_CHCONF_WL_MASK;
423 	confr |= (priv->wordlen - 1) << 7;
424 
425 	omap3_spi_write_chconf(priv, confr);
426 }
427 
428 static void spi_reset(struct mcspi *regs)
429 {
430 	unsigned int tmp;
431 
432 	writel(OMAP3_MCSPI_SYSCONFIG_SOFTRESET, &regs->sysconfig);
433 	do {
434 		tmp = readl(&regs->sysstatus);
435 	} while (!(tmp & OMAP3_MCSPI_SYSSTATUS_RESETDONE));
436 
437 	writel(OMAP3_MCSPI_SYSCONFIG_AUTOIDLE |
438 	       OMAP3_MCSPI_SYSCONFIG_ENAWAKEUP |
439 	       OMAP3_MCSPI_SYSCONFIG_SMARTIDLE, &regs->sysconfig);
440 
441 	writel(OMAP3_MCSPI_WAKEUPENABLE_WKEN, &regs->wakeupenable);
442 }
443 
444 static void _omap3_spi_claim_bus(struct omap3_spi_priv *priv)
445 {
446 	unsigned int conf;
447 
448 	spi_reset(priv->regs);
449 
450 	/*
451 	 * setup when switching from (reset default) slave mode
452 	 * to single-channel master mode
453 	 */
454 	conf = readl(&priv->regs->modulctrl);
455 	conf &= ~(OMAP3_MCSPI_MODULCTRL_STEST | OMAP3_MCSPI_MODULCTRL_MS);
456 	conf |= OMAP3_MCSPI_MODULCTRL_SINGLE;
457 
458 	writel(conf, &priv->regs->modulctrl);
459 
460 	_omap3_spi_set_mode(priv);
461 	_omap3_spi_set_speed(priv);
462 }
463 
464 #ifndef CONFIG_DM_SPI
465 
466 static inline struct omap3_spi_priv *to_omap3_spi(struct spi_slave *slave)
467 {
468 	return container_of(slave, struct omap3_spi_priv, slave);
469 }
470 
471 void spi_init(void)
472 {
473 	/* do nothing */
474 }
475 
476 void spi_free_slave(struct spi_slave *slave)
477 {
478 	struct omap3_spi_priv *priv = to_omap3_spi(slave);
479 
480 	free(priv);
481 }
482 
483 int spi_claim_bus(struct spi_slave *slave)
484 {
485 	struct omap3_spi_priv *priv = to_omap3_spi(slave);
486 
487 	_omap3_spi_claim_bus(priv);
488 	_omap3_spi_set_wordlen(priv);
489 	_omap3_spi_set_mode(priv);
490 	_omap3_spi_set_speed(priv);
491 
492 	return 0;
493 }
494 
495 void spi_release_bus(struct spi_slave *slave)
496 {
497 	struct omap3_spi_priv *priv = to_omap3_spi(slave);
498 
499 	/* Reset the SPI hardware */
500 	spi_reset(priv->regs);
501 }
502 
503 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
504 				     unsigned int max_hz, unsigned int mode)
505 {
506 	struct omap3_spi_priv *priv;
507 	struct mcspi *regs;
508 
509 	/*
510 	 * OMAP3 McSPI (MultiChannel SPI) has 4 busses (modules)
511 	 * with different number of chip selects (CS, channels):
512 	 * McSPI1 has 4 CS (bus 0, cs 0 - 3)
513 	 * McSPI2 has 2 CS (bus 1, cs 0 - 1)
514 	 * McSPI3 has 2 CS (bus 2, cs 0 - 1)
515 	 * McSPI4 has 1 CS (bus 3, cs 0)
516 	 */
517 
518 	switch (bus) {
519 	case 0:
520 		 regs = (struct mcspi *)OMAP3_MCSPI1_BASE;
521 		 break;
522 #ifdef OMAP3_MCSPI2_BASE
523 	case 1:
524 		 regs = (struct mcspi *)OMAP3_MCSPI2_BASE;
525 		 break;
526 #endif
527 #ifdef OMAP3_MCSPI3_BASE
528 	case 2:
529 		 regs = (struct mcspi *)OMAP3_MCSPI3_BASE;
530 		 break;
531 #endif
532 #ifdef OMAP3_MCSPI4_BASE
533 	case 3:
534 		 regs = (struct mcspi *)OMAP3_MCSPI4_BASE;
535 		 break;
536 #endif
537 	default:
538 		 printf("SPI error: unsupported bus %i.  Supported busses 0 - 3\n", bus);
539 		 return NULL;
540 	}
541 
542 	if (((bus == 0) && (cs > 3)) ||
543 	    ((bus == 1) && (cs > 1)) ||
544 	    ((bus == 2) && (cs > 1)) ||
545 	    ((bus == 3) && (cs > 0))) {
546 		printf("SPI error: unsupported chip select %i on bus %i\n", cs, bus);
547 		return NULL;
548 	}
549 
550 	if (max_hz > OMAP3_MCSPI_MAX_FREQ) {
551 		printf("SPI error: unsupported frequency %i Hz. Max frequency is 48 Mhz\n", max_hz);
552 		return NULL;
553 	}
554 
555 	if (mode > SPI_MODE_3) {
556 		printf("SPI error: unsupported SPI mode %i\n", mode);
557 		return NULL;
558 	}
559 
560 	priv = spi_alloc_slave(struct omap3_spi_priv, bus, cs);
561 	if (!priv) {
562 		printf("SPI error: malloc of SPI structure failed\n");
563 		return NULL;
564 	}
565 
566 	priv->regs = regs;
567 	priv->cs = cs;
568 	priv->freq = max_hz;
569 	priv->mode = mode;
570 	priv->wordlen = priv->slave.wordlen;
571 #ifdef CONFIG_OMAP3_SPI_D0_D1_SWAPPED
572 	priv->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
573 #endif
574 
575 	return &priv->slave;
576 }
577 
578 int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
579 	     const void *dout, void *din, unsigned long flags)
580 {
581 	struct omap3_spi_priv *priv = to_omap3_spi(slave);
582 
583 	return _spi_xfer(priv, bitlen, dout, din, flags);
584 }
585 
586 #else
587 
588 static int omap3_spi_claim_bus(struct udevice *dev)
589 {
590 	struct udevice *bus = dev->parent;
591 	struct omap3_spi_priv *priv = dev_get_priv(bus);
592 	struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
593 
594 	priv->cs = slave_plat->cs;
595 	priv->mode = slave_plat->mode;
596 	priv->freq = slave_plat->max_hz;
597 	_omap3_spi_claim_bus(priv);
598 
599 	return 0;
600 }
601 
602 static int omap3_spi_release_bus(struct udevice *dev)
603 {
604 	struct udevice *bus = dev->parent;
605 	struct omap3_spi_priv *priv = dev_get_priv(bus);
606 
607 	/* Reset the SPI hardware */
608 	spi_reset(priv->regs);
609 
610 	return 0;
611 }
612 
613 static int omap3_spi_set_wordlen(struct udevice *dev, unsigned int wordlen)
614 {
615 	struct udevice *bus = dev->parent;
616 	struct omap3_spi_priv *priv = dev_get_priv(bus);
617 	struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
618 
619 	priv->cs = slave_plat->cs;
620 	priv->wordlen = wordlen;
621 	_omap3_spi_set_wordlen(priv);
622 
623 	return 0;
624 }
625 
626 static int omap3_spi_probe(struct udevice *dev)
627 {
628 	struct omap3_spi_priv *priv = dev_get_priv(dev);
629 	const void *blob = gd->fdt_blob;
630 	int node = dev_of_offset(dev);
631 
632 	struct omap2_mcspi_platform_config* data =
633 		(struct omap2_mcspi_platform_config*)dev_get_driver_data(dev);
634 
635 	priv->regs = (struct mcspi *)(dev_get_addr(dev) + data->regs_offset);
636 	priv->pin_dir = fdtdec_get_uint(blob, node, "ti,pindir-d0-out-d1-in",
637 					    MCSPI_PINDIR_D0_IN_D1_OUT);
638 	priv->wordlen = SPI_DEFAULT_WORDLEN;
639 	return 0;
640 }
641 
642 static int omap3_spi_xfer(struct udevice *dev, unsigned int bitlen,
643 			    const void *dout, void *din, unsigned long flags)
644 {
645 	struct udevice *bus = dev->parent;
646 	struct omap3_spi_priv *priv = dev_get_priv(bus);
647 
648 	return _spi_xfer(priv, bitlen, dout, din, flags);
649 }
650 
651 static int omap3_spi_set_speed(struct udevice *bus, unsigned int speed)
652 {
653 	return 0;
654 }
655 
656 static int omap3_spi_set_mode(struct udevice *bus, uint mode)
657 {
658 	return 0;
659 }
660 
661 static const struct dm_spi_ops omap3_spi_ops = {
662 	.claim_bus      = omap3_spi_claim_bus,
663 	.release_bus    = omap3_spi_release_bus,
664 	.set_wordlen    = omap3_spi_set_wordlen,
665 	.xfer	    = omap3_spi_xfer,
666 	.set_speed      = omap3_spi_set_speed,
667 	.set_mode	= omap3_spi_set_mode,
668 	/*
669 	 * cs_info is not needed, since we require all chip selects to be
670 	 * in the device tree explicitly
671 	 */
672 };
673 
674 static struct omap2_mcspi_platform_config omap2_pdata = {
675 	.regs_offset = 0,
676 };
677 
678 static struct omap2_mcspi_platform_config omap4_pdata = {
679 	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
680 };
681 
682 static const struct udevice_id omap3_spi_ids[] = {
683 	{ .compatible = "ti,omap2-mcspi", .data = (ulong)&omap2_pdata },
684 	{ .compatible = "ti,omap4-mcspi", .data = (ulong)&omap4_pdata },
685 	{ }
686 };
687 
688 U_BOOT_DRIVER(omap3_spi) = {
689 	.name   = "omap3_spi",
690 	.id     = UCLASS_SPI,
691 	.of_match = omap3_spi_ids,
692 	.probe = omap3_spi_probe,
693 	.ops    = &omap3_spi_ops,
694 	.priv_auto_alloc_size = sizeof(struct omap3_spi_priv),
695 };
696 #endif
697