xref: /openbmc/u-boot/drivers/spi/omap3_spi.c (revision f7440928)
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 /* per-register bitmasks */
39 #define OMAP3_MCSPI_SYSCONFIG_SMARTIDLE (2 << 3)
40 #define OMAP3_MCSPI_SYSCONFIG_ENAWAKEUP BIT(2)
41 #define OMAP3_MCSPI_SYSCONFIG_AUTOIDLE	BIT(0)
42 #define OMAP3_MCSPI_SYSCONFIG_SOFTRESET BIT(1)
43 
44 #define OMAP3_MCSPI_SYSSTATUS_RESETDONE BIT(0)
45 
46 #define OMAP3_MCSPI_MODULCTRL_SINGLE	BIT(0)
47 #define OMAP3_MCSPI_MODULCTRL_MS	BIT(2)
48 #define OMAP3_MCSPI_MODULCTRL_STEST	BIT(3)
49 
50 #define OMAP3_MCSPI_CHCONF_PHA		BIT(0)
51 #define OMAP3_MCSPI_CHCONF_POL		BIT(1)
52 #define OMAP3_MCSPI_CHCONF_CLKD_MASK	GENMASK(5, 2)
53 #define OMAP3_MCSPI_CHCONF_EPOL		BIT(6)
54 #define OMAP3_MCSPI_CHCONF_WL_MASK	GENMASK(11, 7)
55 #define OMAP3_MCSPI_CHCONF_TRM_RX_ONLY	BIT(12)
56 #define OMAP3_MCSPI_CHCONF_TRM_TX_ONLY	BIT(13)
57 #define OMAP3_MCSPI_CHCONF_TRM_MASK	GENMASK(13, 12)
58 #define OMAP3_MCSPI_CHCONF_DMAW		BIT(14)
59 #define OMAP3_MCSPI_CHCONF_DMAR		BIT(15)
60 #define OMAP3_MCSPI_CHCONF_DPE0		BIT(16)
61 #define OMAP3_MCSPI_CHCONF_DPE1		BIT(17)
62 #define OMAP3_MCSPI_CHCONF_IS		BIT(18)
63 #define OMAP3_MCSPI_CHCONF_TURBO	BIT(19)
64 #define OMAP3_MCSPI_CHCONF_FORCE	BIT(20)
65 
66 #define OMAP3_MCSPI_CHSTAT_RXS		BIT(0)
67 #define OMAP3_MCSPI_CHSTAT_TXS		BIT(1)
68 #define OMAP3_MCSPI_CHSTAT_EOT		BIT(2)
69 
70 #define OMAP3_MCSPI_CHCTRL_EN		BIT(0)
71 #define OMAP3_MCSPI_CHCTRL_DIS		(0 << 0)
72 
73 #define OMAP3_MCSPI_WAKEUPENABLE_WKEN	BIT(0)
74 #define MCSPI_PINDIR_D0_IN_D1_OUT	0
75 #define MCSPI_PINDIR_D0_OUT_D1_IN	1
76 
77 #define OMAP3_MCSPI_MAX_FREQ		48000000
78 #define SPI_WAIT_TIMEOUT		10
79 
80 /* OMAP3 McSPI registers */
81 struct mcspi_channel {
82 	unsigned int chconf;		/* 0x2C, 0x40, 0x54, 0x68 */
83 	unsigned int chstat;		/* 0x30, 0x44, 0x58, 0x6C */
84 	unsigned int chctrl;		/* 0x34, 0x48, 0x5C, 0x70 */
85 	unsigned int tx;		/* 0x38, 0x4C, 0x60, 0x74 */
86 	unsigned int rx;		/* 0x3C, 0x50, 0x64, 0x78 */
87 };
88 
89 struct mcspi {
90 	unsigned char res1[0x10];
91 	unsigned int sysconfig;		/* 0x10 */
92 	unsigned int sysstatus;		/* 0x14 */
93 	unsigned int irqstatus;		/* 0x18 */
94 	unsigned int irqenable;		/* 0x1C */
95 	unsigned int wakeupenable;	/* 0x20 */
96 	unsigned int syst;		/* 0x24 */
97 	unsigned int modulctrl;		/* 0x28 */
98 	struct mcspi_channel channel[4];
99 	/* channel0: 0x2C - 0x3C, bus 0 & 1 & 2 & 3 */
100 	/* channel1: 0x40 - 0x50, bus 0 & 1 */
101 	/* channel2: 0x54 - 0x64, bus 0 & 1 */
102 	/* channel3: 0x68 - 0x78, bus 0 */
103 };
104 
105 struct omap3_spi_priv {
106 #ifndef CONFIG_DM_SPI
107 	struct spi_slave slave;
108 #endif
109 	struct mcspi *regs;
110 	unsigned int cs;
111 	unsigned int freq;
112 	unsigned int mode;
113 	unsigned int wordlen;
114 	unsigned int pin_dir:1;
115 };
116 
117 static void omap3_spi_write_chconf(struct omap3_spi_priv *priv, int val)
118 {
119 	writel(val, &priv->regs->channel[priv->cs].chconf);
120 	/* Flash post writes to make immediate effect */
121 	readl(&priv->regs->channel[priv->cs].chconf);
122 }
123 
124 static void omap3_spi_set_enable(struct omap3_spi_priv *priv, int enable)
125 {
126 	writel(enable, &priv->regs->channel[priv->cs].chctrl);
127 	/* Flash post writes to make immediate effect */
128 	readl(&priv->regs->channel[priv->cs].chctrl);
129 }
130 
131 static int omap3_spi_write(struct omap3_spi_priv *priv, unsigned int len,
132 			   const void *txp, unsigned long flags)
133 {
134 	ulong start;
135 	int i, chconf;
136 
137 	chconf = readl(&priv->regs->channel[priv->cs].chconf);
138 
139 	/* Enable the channel */
140 	omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_EN);
141 
142 	chconf &= ~(OMAP3_MCSPI_CHCONF_TRM_MASK | OMAP3_MCSPI_CHCONF_WL_MASK);
143 	chconf |= (priv->wordlen - 1) << 7;
144 	chconf |= OMAP3_MCSPI_CHCONF_TRM_TX_ONLY;
145 	chconf |= OMAP3_MCSPI_CHCONF_FORCE;
146 	omap3_spi_write_chconf(priv, chconf);
147 
148 	for (i = 0; i < len; i++) {
149 		/* wait till TX register is empty (TXS == 1) */
150 		start = get_timer(0);
151 		while (!(readl(&priv->regs->channel[priv->cs].chstat) &
152 			 OMAP3_MCSPI_CHSTAT_TXS)) {
153 			if (get_timer(start) > SPI_WAIT_TIMEOUT) {
154 				printf("SPI TXS timed out, status=0x%08x\n",
155 					readl(&priv->regs->channel[priv->cs].chstat));
156 				return -1;
157 			}
158 		}
159 		/* Write the data */
160 		unsigned int *tx = &priv->regs->channel[priv->cs].tx;
161 		if (priv->wordlen > 16)
162 			writel(((u32 *)txp)[i], tx);
163 		else if (priv->wordlen > 8)
164 			writel(((u16 *)txp)[i], tx);
165 		else
166 			writel(((u8 *)txp)[i], tx);
167 	}
168 
169 	/* wait to finish of transfer */
170 	while ((readl(&priv->regs->channel[priv->cs].chstat) &
171 			(OMAP3_MCSPI_CHSTAT_EOT | OMAP3_MCSPI_CHSTAT_TXS)) !=
172 			(OMAP3_MCSPI_CHSTAT_EOT | OMAP3_MCSPI_CHSTAT_TXS))
173 		;
174 
175 	/* Disable the channel otherwise the next immediate RX will get affected */
176 	omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_DIS);
177 
178 	if (flags & SPI_XFER_END) {
179 
180 		chconf &= ~OMAP3_MCSPI_CHCONF_FORCE;
181 		omap3_spi_write_chconf(priv, chconf);
182 	}
183 	return 0;
184 }
185 
186 static int omap3_spi_read(struct omap3_spi_priv *priv, unsigned int len,
187 			  void *rxp, unsigned long flags)
188 {
189 	int i, chconf;
190 	ulong start;
191 
192 	chconf = readl(&priv->regs->channel[priv->cs].chconf);
193 
194 	/* Enable the channel */
195 	omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_EN);
196 
197 	chconf &= ~(OMAP3_MCSPI_CHCONF_TRM_MASK | OMAP3_MCSPI_CHCONF_WL_MASK);
198 	chconf |= (priv->wordlen - 1) << 7;
199 	chconf |= OMAP3_MCSPI_CHCONF_TRM_RX_ONLY;
200 	chconf |= OMAP3_MCSPI_CHCONF_FORCE;
201 	omap3_spi_write_chconf(priv, chconf);
202 
203 	writel(0, &priv->regs->channel[priv->cs].tx);
204 
205 	for (i = 0; i < len; i++) {
206 		start = get_timer(0);
207 		/* Wait till RX register contains data (RXS == 1) */
208 		while (!(readl(&priv->regs->channel[priv->cs].chstat) &
209 			 OMAP3_MCSPI_CHSTAT_RXS)) {
210 			if (get_timer(start) > SPI_WAIT_TIMEOUT) {
211 				printf("SPI RXS timed out, status=0x%08x\n",
212 					readl(&priv->regs->channel[priv->cs].chstat));
213 				return -1;
214 			}
215 		}
216 
217 		/* Disable the channel to prevent furher receiving */
218 		if (i == (len - 1))
219 			omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_DIS);
220 
221 		/* Read the data */
222 		unsigned int *rx = &priv->regs->channel[priv->cs].rx;
223 		if (priv->wordlen > 16)
224 			((u32 *)rxp)[i] = readl(rx);
225 		else if (priv->wordlen > 8)
226 			((u16 *)rxp)[i] = (u16)readl(rx);
227 		else
228 			((u8 *)rxp)[i] = (u8)readl(rx);
229 	}
230 
231 	if (flags & SPI_XFER_END) {
232 		chconf &= ~OMAP3_MCSPI_CHCONF_FORCE;
233 		omap3_spi_write_chconf(priv, chconf);
234 	}
235 
236 	return 0;
237 }
238 
239 /*McSPI Transmit Receive Mode*/
240 static int omap3_spi_txrx(struct omap3_spi_priv *priv, unsigned int len,
241 			  const void *txp, void *rxp, unsigned long flags)
242 {
243 	ulong start;
244 	int chconf, i = 0;
245 
246 	chconf = readl(&priv->regs->channel[priv->cs].chconf);
247 
248 	/*Enable SPI channel*/
249 	omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_EN);
250 
251 	/*set TRANSMIT-RECEIVE Mode*/
252 	chconf &= ~(OMAP3_MCSPI_CHCONF_TRM_MASK | OMAP3_MCSPI_CHCONF_WL_MASK);
253 	chconf |= (priv->wordlen - 1) << 7;
254 	chconf |= OMAP3_MCSPI_CHCONF_FORCE;
255 	omap3_spi_write_chconf(priv, chconf);
256 
257 	/*Shift in and out 1 byte at time*/
258 	for (i=0; i < len; i++){
259 		/* Write: wait for TX empty (TXS == 1)*/
260 		start = get_timer(0);
261 		while (!(readl(&priv->regs->channel[priv->cs].chstat) &
262 			 OMAP3_MCSPI_CHSTAT_TXS)) {
263 			if (get_timer(start) > SPI_WAIT_TIMEOUT) {
264 				printf("SPI TXS timed out, status=0x%08x\n",
265 					readl(&priv->regs->channel[priv->cs].chstat));
266 				return -1;
267 			}
268 		}
269 		/* Write the data */
270 		unsigned int *tx = &priv->regs->channel[priv->cs].tx;
271 		if (priv->wordlen > 16)
272 			writel(((u32 *)txp)[i], tx);
273 		else if (priv->wordlen > 8)
274 			writel(((u16 *)txp)[i], tx);
275 		else
276 			writel(((u8 *)txp)[i], tx);
277 
278 		/*Read: wait for RX containing data (RXS == 1)*/
279 		start = get_timer(0);
280 		while (!(readl(&priv->regs->channel[priv->cs].chstat) &
281 			 OMAP3_MCSPI_CHSTAT_RXS)) {
282 			if (get_timer(start) > SPI_WAIT_TIMEOUT) {
283 				printf("SPI RXS timed out, status=0x%08x\n",
284 					readl(&priv->regs->channel[priv->cs].chstat));
285 				return -1;
286 			}
287 		}
288 		/* Read the data */
289 		unsigned int *rx = &priv->regs->channel[priv->cs].rx;
290 		if (priv->wordlen > 16)
291 			((u32 *)rxp)[i] = readl(rx);
292 		else if (priv->wordlen > 8)
293 			((u16 *)rxp)[i] = (u16)readl(rx);
294 		else
295 			((u8 *)rxp)[i] = (u8)readl(rx);
296 	}
297 	/* Disable the channel */
298 	omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_DIS);
299 
300 	/*if transfer must be terminated disable the channel*/
301 	if (flags & SPI_XFER_END) {
302 		chconf &= ~OMAP3_MCSPI_CHCONF_FORCE;
303 		omap3_spi_write_chconf(priv, chconf);
304 	}
305 
306 	return 0;
307 }
308 
309 static int _spi_xfer(struct omap3_spi_priv *priv, unsigned int bitlen,
310 		     const void *dout, void *din, unsigned long flags)
311 {
312 	unsigned int	len;
313 	int ret = -1;
314 
315 	if (priv->wordlen < 4 || priv->wordlen > 32) {
316 		printf("omap3_spi: invalid wordlen %d\n", priv->wordlen);
317 		return -1;
318 	}
319 
320 	if (bitlen % priv->wordlen)
321 		return -1;
322 
323 	len = bitlen / priv->wordlen;
324 
325 	if (bitlen == 0) {	 /* only change CS */
326 		int chconf = readl(&priv->regs->channel[priv->cs].chconf);
327 
328 		if (flags & SPI_XFER_BEGIN) {
329 			omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_EN);
330 			chconf |= OMAP3_MCSPI_CHCONF_FORCE;
331 			omap3_spi_write_chconf(priv, chconf);
332 		}
333 		if (flags & SPI_XFER_END) {
334 			chconf &= ~OMAP3_MCSPI_CHCONF_FORCE;
335 			omap3_spi_write_chconf(priv, chconf);
336 			omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_DIS);
337 		}
338 		ret = 0;
339 	} else {
340 		if (dout != NULL && din != NULL)
341 			ret = omap3_spi_txrx(priv, len, dout, din, flags);
342 		else if (dout != NULL)
343 			ret = omap3_spi_write(priv, len, dout, flags);
344 		else if (din != NULL)
345 			ret = omap3_spi_read(priv, len, din, flags);
346 	}
347 	return ret;
348 }
349 
350 static void _omap3_spi_set_speed(struct omap3_spi_priv *priv)
351 {
352 	uint32_t confr, div = 0;
353 
354 	confr = readl(&priv->regs->channel[priv->cs].chconf);
355 
356 	/* Calculate clock divisor. Valid range: 0x0 - 0xC ( /1 - /4096 ) */
357 	if (priv->freq) {
358 		while (div <= 0xC && (OMAP3_MCSPI_MAX_FREQ / (1 << div))
359 					> priv->freq)
360 			div++;
361 	} else {
362 		 div = 0xC;
363 	}
364 
365 	/* set clock divisor */
366 	confr &= ~OMAP3_MCSPI_CHCONF_CLKD_MASK;
367 	confr |= div << 2;
368 
369 	omap3_spi_write_chconf(priv, confr);
370 }
371 
372 static void _omap3_spi_set_mode(struct omap3_spi_priv *priv)
373 {
374 	uint32_t confr;
375 
376 	confr = readl(&priv->regs->channel[priv->cs].chconf);
377 
378 	/* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
379 	 * REVISIT: this controller could support SPI_3WIRE mode.
380 	 */
381 	if (priv->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
382 		confr &= ~(OMAP3_MCSPI_CHCONF_IS|OMAP3_MCSPI_CHCONF_DPE1);
383 		confr |= OMAP3_MCSPI_CHCONF_DPE0;
384 	} else {
385 		confr &= ~OMAP3_MCSPI_CHCONF_DPE0;
386 		confr |= OMAP3_MCSPI_CHCONF_IS|OMAP3_MCSPI_CHCONF_DPE1;
387 	}
388 
389 	/* set SPI mode 0..3 */
390 	confr &= ~(OMAP3_MCSPI_CHCONF_POL | OMAP3_MCSPI_CHCONF_PHA);
391 	if (priv->mode & SPI_CPHA)
392 		confr |= OMAP3_MCSPI_CHCONF_PHA;
393 	if (priv->mode & SPI_CPOL)
394 		confr |= OMAP3_MCSPI_CHCONF_POL;
395 
396 	/* set chipselect polarity; manage with FORCE */
397 	if (!(priv->mode & SPI_CS_HIGH))
398 		confr |= OMAP3_MCSPI_CHCONF_EPOL; /* active-low; normal */
399 	else
400 		confr &= ~OMAP3_MCSPI_CHCONF_EPOL;
401 
402 	/* Transmit & receive mode */
403 	confr &= ~OMAP3_MCSPI_CHCONF_TRM_MASK;
404 
405 	omap3_spi_write_chconf(priv, confr);
406 }
407 
408 static void _omap3_spi_set_wordlen(struct omap3_spi_priv *priv)
409 {
410 	unsigned int confr;
411 
412 	/* McSPI individual channel configuration */
413 	confr = readl(&priv->regs->channel[priv->wordlen].chconf);
414 
415 	/* wordlength */
416 	confr &= ~OMAP3_MCSPI_CHCONF_WL_MASK;
417 	confr |= (priv->wordlen - 1) << 7;
418 
419 	omap3_spi_write_chconf(priv, confr);
420 }
421 
422 static void spi_reset(struct mcspi *regs)
423 {
424 	unsigned int tmp;
425 
426 	writel(OMAP3_MCSPI_SYSCONFIG_SOFTRESET, &regs->sysconfig);
427 	do {
428 		tmp = readl(&regs->sysstatus);
429 	} while (!(tmp & OMAP3_MCSPI_SYSSTATUS_RESETDONE));
430 
431 	writel(OMAP3_MCSPI_SYSCONFIG_AUTOIDLE |
432 	       OMAP3_MCSPI_SYSCONFIG_ENAWAKEUP |
433 	       OMAP3_MCSPI_SYSCONFIG_SMARTIDLE, &regs->sysconfig);
434 
435 	writel(OMAP3_MCSPI_WAKEUPENABLE_WKEN, &regs->wakeupenable);
436 }
437 
438 static void _omap3_spi_claim_bus(struct omap3_spi_priv *priv)
439 {
440 	unsigned int conf;
441 
442 	spi_reset(priv->regs);
443 
444 	/*
445 	 * setup when switching from (reset default) slave mode
446 	 * to single-channel master mode
447 	 */
448 	conf = readl(&priv->regs->modulctrl);
449 	conf &= ~(OMAP3_MCSPI_MODULCTRL_STEST | OMAP3_MCSPI_MODULCTRL_MS);
450 	conf |= OMAP3_MCSPI_MODULCTRL_SINGLE;
451 
452 	writel(conf, &priv->regs->modulctrl);
453 
454 	_omap3_spi_set_mode(priv);
455 	_omap3_spi_set_speed(priv);
456 }
457 
458 #ifndef CONFIG_DM_SPI
459 
460 static inline struct omap3_spi_priv *to_omap3_spi(struct spi_slave *slave)
461 {
462 	return container_of(slave, struct omap3_spi_priv, slave);
463 }
464 
465 void spi_init(void)
466 {
467 	/* do nothing */
468 }
469 
470 void spi_free_slave(struct spi_slave *slave)
471 {
472 	struct omap3_spi_priv *priv = to_omap3_spi(slave);
473 
474 	free(priv);
475 }
476 
477 int spi_claim_bus(struct spi_slave *slave)
478 {
479 	struct omap3_spi_priv *priv = to_omap3_spi(slave);
480 
481 	_omap3_spi_claim_bus(priv);
482 	_omap3_spi_set_wordlen(priv);
483 	_omap3_spi_set_mode(priv);
484 	_omap3_spi_set_speed(priv);
485 
486 	return 0;
487 }
488 
489 void spi_release_bus(struct spi_slave *slave)
490 {
491 	struct omap3_spi_priv *priv = to_omap3_spi(slave);
492 
493 	/* Reset the SPI hardware */
494 	spi_reset(priv->regs);
495 }
496 
497 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
498 				     unsigned int max_hz, unsigned int mode)
499 {
500 	struct omap3_spi_priv *priv;
501 	struct mcspi *regs;
502 
503 	/*
504 	 * OMAP3 McSPI (MultiChannel SPI) has 4 busses (modules)
505 	 * with different number of chip selects (CS, channels):
506 	 * McSPI1 has 4 CS (bus 0, cs 0 - 3)
507 	 * McSPI2 has 2 CS (bus 1, cs 0 - 1)
508 	 * McSPI3 has 2 CS (bus 2, cs 0 - 1)
509 	 * McSPI4 has 1 CS (bus 3, cs 0)
510 	 */
511 
512 	switch (bus) {
513 	case 0:
514 		 regs = (struct mcspi *)OMAP3_MCSPI1_BASE;
515 		 break;
516 #ifdef OMAP3_MCSPI2_BASE
517 	case 1:
518 		 regs = (struct mcspi *)OMAP3_MCSPI2_BASE;
519 		 break;
520 #endif
521 #ifdef OMAP3_MCSPI3_BASE
522 	case 2:
523 		 regs = (struct mcspi *)OMAP3_MCSPI3_BASE;
524 		 break;
525 #endif
526 #ifdef OMAP3_MCSPI4_BASE
527 	case 3:
528 		 regs = (struct mcspi *)OMAP3_MCSPI4_BASE;
529 		 break;
530 #endif
531 	default:
532 		 printf("SPI error: unsupported bus %i.  Supported busses 0 - 3\n", bus);
533 		 return NULL;
534 	}
535 
536 	if (((bus == 0) && (cs > 3)) ||
537 	    ((bus == 1) && (cs > 1)) ||
538 	    ((bus == 2) && (cs > 1)) ||
539 	    ((bus == 3) && (cs > 0))) {
540 		printf("SPI error: unsupported chip select %i on bus %i\n", cs, bus);
541 		return NULL;
542 	}
543 
544 	if (max_hz > OMAP3_MCSPI_MAX_FREQ) {
545 		printf("SPI error: unsupported frequency %i Hz. Max frequency is 48 Mhz\n", max_hz);
546 		return NULL;
547 	}
548 
549 	if (mode > SPI_MODE_3) {
550 		printf("SPI error: unsupported SPI mode %i\n", mode);
551 		return NULL;
552 	}
553 
554 	priv = spi_alloc_slave(struct omap3_spi_priv, bus, cs);
555 	if (!priv) {
556 		printf("SPI error: malloc of SPI structure failed\n");
557 		return NULL;
558 	}
559 
560 	priv->regs = regs;
561 	priv->cs = cs;
562 	priv->freq = max_hz;
563 	priv->mode = mode;
564 	priv->wordlen = priv->slave.wordlen;
565 #ifdef CONFIG_OMAP3_SPI_D0_D1_SWAPPED
566 	priv->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
567 #endif
568 
569 	return &priv->slave;
570 }
571 
572 int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
573 	     const void *dout, void *din, unsigned long flags)
574 {
575 	struct omap3_spi_priv *priv = to_omap3_spi(slave);
576 
577 	return _spi_xfer(priv, bitlen, dout, din, flags);
578 }
579 
580 #else
581 
582 static int omap3_spi_claim_bus(struct udevice *dev)
583 {
584 	struct udevice *bus = dev->parent;
585 	struct omap3_spi_priv *priv = dev_get_priv(bus);
586 	struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
587 
588 	priv->cs = slave_plat->cs;
589 	priv->mode = slave_plat->mode;
590 	priv->freq = slave_plat->max_hz;
591 	_omap3_spi_claim_bus(priv);
592 
593 	return 0;
594 }
595 
596 static int omap3_spi_release_bus(struct udevice *dev)
597 {
598 	struct udevice *bus = dev->parent;
599 	struct omap3_spi_priv *priv = dev_get_priv(bus);
600 
601 	/* Reset the SPI hardware */
602 	spi_reset(priv->regs);
603 
604 	return 0;
605 }
606 
607 static int omap3_spi_set_wordlen(struct udevice *dev, unsigned int wordlen)
608 {
609 	struct udevice *bus = dev->parent;
610 	struct omap3_spi_priv *priv = dev_get_priv(bus);
611 	struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
612 
613 	priv->cs = slave_plat->cs;
614 	priv->wordlen = wordlen;
615 	_omap3_spi_set_wordlen(priv);
616 
617 	return 0;
618 }
619 
620 static int omap3_spi_probe(struct udevice *dev)
621 {
622 	struct omap3_spi_priv *priv = dev_get_priv(dev);
623 	const void *blob = gd->fdt_blob;
624 	int node = dev->of_offset;
625 
626 	priv->regs = (struct mcspi *)dev_get_addr(dev);
627 	priv->pin_dir = fdtdec_get_uint(blob, node, "ti,pindir-d0-out-d1-in",
628 					    MCSPI_PINDIR_D0_IN_D1_OUT);
629 	priv->wordlen = SPI_DEFAULT_WORDLEN;
630 	return 0;
631 }
632 
633 static int omap3_spi_xfer(struct udevice *dev, unsigned int bitlen,
634 			    const void *dout, void *din, unsigned long flags)
635 {
636 	struct udevice *bus = dev->parent;
637 	struct omap3_spi_priv *priv = dev_get_priv(bus);
638 
639 	return _spi_xfer(priv, bitlen, dout, din, flags);
640 }
641 
642 static int omap3_spi_set_speed(struct udevice *bus, unsigned int speed)
643 {
644 	return 0;
645 }
646 
647 static int omap3_spi_set_mode(struct udevice *bus, uint mode)
648 {
649 	return 0;
650 }
651 
652 static const struct dm_spi_ops omap3_spi_ops = {
653 	.claim_bus      = omap3_spi_claim_bus,
654 	.release_bus    = omap3_spi_release_bus,
655 	.set_wordlen    = omap3_spi_set_wordlen,
656 	.xfer	    = omap3_spi_xfer,
657 	.set_speed      = omap3_spi_set_speed,
658 	.set_mode	= omap3_spi_set_mode,
659 	/*
660 	 * cs_info is not needed, since we require all chip selects to be
661 	 * in the device tree explicitly
662 	 */
663 };
664 
665 static const struct udevice_id omap3_spi_ids[] = {
666 	{ .compatible = "ti,omap2-mcspi" },
667 	{ .compatible = "ti,omap4-mcspi" },
668 	{ }
669 };
670 
671 U_BOOT_DRIVER(omap3_spi) = {
672 	.name   = "omap3_spi",
673 	.id     = UCLASS_SPI,
674 	.of_match = omap3_spi_ids,
675 	.probe = omap3_spi_probe,
676 	.ops    = &omap3_spi_ops,
677 	.priv_auto_alloc_size = sizeof(struct omap3_spi_priv),
678 	.probe = omap3_spi_probe,
679 };
680 #endif
681