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    /*
    
     * Copyright (C) 2016 Jagan Teki <jteki@openedev.com>
     *		      Christophe Ricard <christophe.ricard@gmail.com>
     *
    
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     * Copyright (C) 2010 Dirk Behme <dirk.behme@googlemail.com>
     *
     * Driver for McSPI controller on OMAP3. Based on davinci_spi.c
     * Copyright (C) 2009 Texas Instruments Incorporated - http://www.ti.com/
     *
     * Copyright (C) 2007 Atmel Corporation
     *
     * Parts taken from linux/drivers/spi/omap2_mcspi.c
     * Copyright (C) 2005, 2006 Nokia Corporation
     *
     * Modified by Ruslan Araslanov <ruslan.araslanov@vitecmm.com>
     *
    
     * SPDX-License-Identifier:	GPL-2.0+
    
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     */
    
    #include <common.h>
    
    #include <dm.h>
    
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    #include <spi.h>
    #include <malloc.h>
    #include <asm/io.h>
    
    
    DECLARE_GLOBAL_DATA_PTR;
    
    
    #if defined(CONFIG_AM33XX) || defined(CONFIG_AM43XX)
    #define OMAP3_MCSPI1_BASE	0x48030100
    #define OMAP3_MCSPI2_BASE	0x481A0100
    #else
    #define OMAP3_MCSPI1_BASE	0x48098000
    #define OMAP3_MCSPI2_BASE	0x4809A000
    #define OMAP3_MCSPI3_BASE	0x480B8000
    #define OMAP3_MCSPI4_BASE	0x480BA000
    #endif
    
    /* per-register bitmasks */
    #define OMAP3_MCSPI_SYSCONFIG_SMARTIDLE (2 << 3)
    #define OMAP3_MCSPI_SYSCONFIG_ENAWAKEUP BIT(2)
    #define OMAP3_MCSPI_SYSCONFIG_AUTOIDLE	BIT(0)
    #define OMAP3_MCSPI_SYSCONFIG_SOFTRESET BIT(1)
    
    #define OMAP3_MCSPI_SYSSTATUS_RESETDONE BIT(0)
    
    #define OMAP3_MCSPI_MODULCTRL_SINGLE	BIT(0)
    #define OMAP3_MCSPI_MODULCTRL_MS	BIT(2)
    #define OMAP3_MCSPI_MODULCTRL_STEST	BIT(3)
    
    #define OMAP3_MCSPI_CHCONF_PHA		BIT(0)
    #define OMAP3_MCSPI_CHCONF_POL		BIT(1)
    #define OMAP3_MCSPI_CHCONF_CLKD_MASK	GENMASK(5, 2)
    #define OMAP3_MCSPI_CHCONF_EPOL		BIT(6)
    #define OMAP3_MCSPI_CHCONF_WL_MASK	GENMASK(11, 7)
    #define OMAP3_MCSPI_CHCONF_TRM_RX_ONLY	BIT(12)
    #define OMAP3_MCSPI_CHCONF_TRM_TX_ONLY	BIT(13)
    #define OMAP3_MCSPI_CHCONF_TRM_MASK	GENMASK(13, 12)
    #define OMAP3_MCSPI_CHCONF_DMAW		BIT(14)
    #define OMAP3_MCSPI_CHCONF_DMAR		BIT(15)
    #define OMAP3_MCSPI_CHCONF_DPE0		BIT(16)
    #define OMAP3_MCSPI_CHCONF_DPE1		BIT(17)
    #define OMAP3_MCSPI_CHCONF_IS		BIT(18)
    #define OMAP3_MCSPI_CHCONF_TURBO	BIT(19)
    #define OMAP3_MCSPI_CHCONF_FORCE	BIT(20)
    
    #define OMAP3_MCSPI_CHSTAT_RXS		BIT(0)
    #define OMAP3_MCSPI_CHSTAT_TXS		BIT(1)
    #define OMAP3_MCSPI_CHSTAT_EOT		BIT(2)
    
    #define OMAP3_MCSPI_CHCTRL_EN		BIT(0)
    #define OMAP3_MCSPI_CHCTRL_DIS		(0 << 0)
    
    #define OMAP3_MCSPI_WAKEUPENABLE_WKEN	BIT(0)
    
    #define MCSPI_PINDIR_D0_IN_D1_OUT	0
    #define MCSPI_PINDIR_D0_OUT_D1_IN	1
    
    
    #define OMAP3_MCSPI_MAX_FREQ		48000000
    #define SPI_WAIT_TIMEOUT		10
    
    /* OMAP3 McSPI registers */
    struct mcspi_channel {
    	unsigned int chconf;		/* 0x2C, 0x40, 0x54, 0x68 */
    	unsigned int chstat;		/* 0x30, 0x44, 0x58, 0x6C */
    	unsigned int chctrl;		/* 0x34, 0x48, 0x5C, 0x70 */
    	unsigned int tx;		/* 0x38, 0x4C, 0x60, 0x74 */
    	unsigned int rx;		/* 0x3C, 0x50, 0x64, 0x78 */
    };
    
    struct mcspi {
    	unsigned char res1[0x10];
    	unsigned int sysconfig;		/* 0x10 */
    	unsigned int sysstatus;		/* 0x14 */
    	unsigned int irqstatus;		/* 0x18 */
    	unsigned int irqenable;		/* 0x1C */
    	unsigned int wakeupenable;	/* 0x20 */
    	unsigned int syst;		/* 0x24 */
    	unsigned int modulctrl;		/* 0x28 */
    	struct mcspi_channel channel[4];
    	/* channel0: 0x2C - 0x3C, bus 0 & 1 & 2 & 3 */
    	/* channel1: 0x40 - 0x50, bus 0 & 1 */
    	/* channel2: 0x54 - 0x64, bus 0 & 1 */
    	/* channel3: 0x68 - 0x78, bus 0 */
    };
    
    
    struct omap3_spi_priv {
    
    	struct mcspi *regs;
    
    	unsigned int cs;
    
    	unsigned int freq;
    	unsigned int mode;
    
    	unsigned int wordlen;
    	unsigned int pin_dir:1;
    
    static void omap3_spi_write_chconf(struct omap3_spi_priv *priv, int val)
    
    	writel(val, &priv->regs->channel[priv->cs].chconf);
    
    	/* Flash post writes to make immediate effect */
    
    	readl(&priv->regs->channel[priv->cs].chconf);
    
    static void omap3_spi_set_enable(struct omap3_spi_priv *priv, int enable)
    
    	writel(enable, &priv->regs->channel[priv->cs].chctrl);
    
    	/* Flash post writes to make immediate effect */
    
    	readl(&priv->regs->channel[priv->cs].chctrl);
    
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    }
    
    
    static int omap3_spi_write(struct omap3_spi_priv *priv, unsigned int len,
    
    			   const void *txp, unsigned long flags)
    
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    {
    
    	ulong start;
    
    	int i, chconf;
    
    	chconf = readl(&priv->regs->channel[priv->cs].chconf);
    
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    	/* Enable the channel */
    
    	omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_EN);
    
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    	chconf &= ~(OMAP3_MCSPI_CHCONF_TRM_MASK | OMAP3_MCSPI_CHCONF_WL_MASK);
    
    	chconf |= (priv->wordlen - 1) << 7;
    
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    	chconf |= OMAP3_MCSPI_CHCONF_TRM_TX_ONLY;
    	chconf |= OMAP3_MCSPI_CHCONF_FORCE;
    
    	omap3_spi_write_chconf(priv, chconf);
    
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    	for (i = 0; i < len; i++) {
    		/* wait till TX register is empty (TXS == 1) */
    
    		start = get_timer(0);
    
    		while (!(readl(&priv->regs->channel[priv->cs].chstat) &
    
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    			 OMAP3_MCSPI_CHSTAT_TXS)) {
    
    			if (get_timer(start) > SPI_WAIT_TIMEOUT) {
    
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    				printf("SPI TXS timed out, status=0x%08x\n",
    
    					readl(&priv->regs->channel[priv->cs].chstat));
    
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    				return -1;
    			}
    		}
    		/* Write the data */
    
    		unsigned int *tx = &priv->regs->channel[priv->cs].tx;
    		if (priv->wordlen > 16)
    
    			writel(((u32 *)txp)[i], tx);
    
    		else if (priv->wordlen > 8)
    
    			writel(((u16 *)txp)[i], tx);
    		else
    			writel(((u8 *)txp)[i], tx);
    
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    	}
    
    
    	/* wait to finish of transfer */
    
    	while ((readl(&priv->regs->channel[priv->cs].chstat) &
    			(OMAP3_MCSPI_CHSTAT_EOT | OMAP3_MCSPI_CHSTAT_TXS)) !=
    			(OMAP3_MCSPI_CHSTAT_EOT | OMAP3_MCSPI_CHSTAT_TXS))
    		;
    
    
    	/* Disable the channel otherwise the next immediate RX will get affected */
    
    	omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_DIS);
    
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    	if (flags & SPI_XFER_END) {
    
    		chconf &= ~OMAP3_MCSPI_CHCONF_FORCE;
    
    		omap3_spi_write_chconf(priv, chconf);
    
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    	}
    	return 0;
    }
    
    
    static int omap3_spi_read(struct omap3_spi_priv *priv, unsigned int len,
    
    			  void *rxp, unsigned long flags)
    
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    {
    
    	int i, chconf;
    
    	ulong start;
    
    
    	chconf = readl(&priv->regs->channel[priv->cs].chconf);
    
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    	/* Enable the channel */
    
    	omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_EN);
    
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    	chconf &= ~(OMAP3_MCSPI_CHCONF_TRM_MASK | OMAP3_MCSPI_CHCONF_WL_MASK);
    
    	chconf |= (priv->wordlen - 1) << 7;
    
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    	chconf |= OMAP3_MCSPI_CHCONF_TRM_RX_ONLY;
    	chconf |= OMAP3_MCSPI_CHCONF_FORCE;
    
    	omap3_spi_write_chconf(priv, chconf);
    
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    	writel(0, &priv->regs->channel[priv->cs].tx);
    
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    	for (i = 0; i < len; i++) {
    
    		start = get_timer(0);
    
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    		/* Wait till RX register contains data (RXS == 1) */
    
    		while (!(readl(&priv->regs->channel[priv->cs].chstat) &
    
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    			 OMAP3_MCSPI_CHSTAT_RXS)) {
    
    			if (get_timer(start) > SPI_WAIT_TIMEOUT) {
    
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    				printf("SPI RXS timed out, status=0x%08x\n",
    
    					readl(&priv->regs->channel[priv->cs].chstat));
    
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    				return -1;
    			}
    		}
    
    
    		/* Disable the channel to prevent furher receiving */
    
    		if (i == (len - 1))
    			omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_DIS);
    
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    		/* Read the data */
    
    		unsigned int *rx = &priv->regs->channel[priv->cs].rx;
    		if (priv->wordlen > 16)
    
    			((u32 *)rxp)[i] = readl(rx);
    
    		else if (priv->wordlen > 8)
    
    			((u16 *)rxp)[i] = (u16)readl(rx);
    		else
    			((u8 *)rxp)[i] = (u8)readl(rx);
    
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    	}
    
    	if (flags & SPI_XFER_END) {
    		chconf &= ~OMAP3_MCSPI_CHCONF_FORCE;
    
    		omap3_spi_write_chconf(priv, chconf);
    
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    	}
    
    	return 0;
    }
    
    
    /*McSPI Transmit Receive Mode*/
    
    static int omap3_spi_txrx(struct omap3_spi_priv *priv, unsigned int len,
    
    			  const void *txp, void *rxp, unsigned long flags)
    
    	ulong start;
    
    	int chconf, i = 0;
    
    	chconf = readl(&priv->regs->channel[priv->cs].chconf);
    
    
    	/*Enable SPI channel*/
    
    	omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_EN);
    
    
    	/*set TRANSMIT-RECEIVE Mode*/
    
    	chconf &= ~(OMAP3_MCSPI_CHCONF_TRM_MASK | OMAP3_MCSPI_CHCONF_WL_MASK);
    
    	chconf |= (priv->wordlen - 1) << 7;
    
    	chconf |= OMAP3_MCSPI_CHCONF_FORCE;
    
    	omap3_spi_write_chconf(priv, chconf);
    
    
    	/*Shift in and out 1 byte at time*/
    	for (i=0; i < len; i++){
    		/* Write: wait for TX empty (TXS == 1)*/
    
    		start = get_timer(0);
    
    		while (!(readl(&priv->regs->channel[priv->cs].chstat) &
    
    			 OMAP3_MCSPI_CHSTAT_TXS)) {
    
    			if (get_timer(start) > SPI_WAIT_TIMEOUT) {
    
    				printf("SPI TXS timed out, status=0x%08x\n",
    
    					readl(&priv->regs->channel[priv->cs].chstat));
    
    				return -1;
    			}
    		}
    		/* Write the data */
    
    		unsigned int *tx = &priv->regs->channel[priv->cs].tx;
    		if (priv->wordlen > 16)
    
    			writel(((u32 *)txp)[i], tx);
    
    		else if (priv->wordlen > 8)
    
    			writel(((u16 *)txp)[i], tx);
    		else
    			writel(((u8 *)txp)[i], tx);
    
    
    		/*Read: wait for RX containing data (RXS == 1)*/
    
    		start = get_timer(0);
    
    		while (!(readl(&priv->regs->channel[priv->cs].chstat) &
    
    			 OMAP3_MCSPI_CHSTAT_RXS)) {
    
    			if (get_timer(start) > SPI_WAIT_TIMEOUT) {
    
    				printf("SPI RXS timed out, status=0x%08x\n",
    
    					readl(&priv->regs->channel[priv->cs].chstat));
    
    				return -1;
    			}
    		}
    		/* Read the data */
    
    		unsigned int *rx = &priv->regs->channel[priv->cs].rx;
    		if (priv->wordlen > 16)
    
    			((u32 *)rxp)[i] = readl(rx);
    
    		else if (priv->wordlen > 8)
    
    			((u16 *)rxp)[i] = (u16)readl(rx);
    		else
    			((u8 *)rxp)[i] = (u8)readl(rx);
    
    	/* Disable the channel */
    
    	omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_DIS);
    
    
    	/*if transfer must be terminated disable the channel*/
    	if (flags & SPI_XFER_END) {
    		chconf &= ~OMAP3_MCSPI_CHCONF_FORCE;
    
    		omap3_spi_write_chconf(priv, chconf);
    
    static int _spi_xfer(struct omap3_spi_priv *priv, unsigned int bitlen,
    		     const void *dout, void *din, unsigned long flags)
    
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    {
    	unsigned int	len;
    	int ret = -1;
    
    
    	if (priv->wordlen < 4 || priv->wordlen > 32) {
    		printf("omap3_spi: invalid wordlen %d\n", priv->wordlen);
    
    	if (bitlen % priv->wordlen)
    
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    		return -1;
    
    
    	len = bitlen / priv->wordlen;
    
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    	if (bitlen == 0) {	 /* only change CS */
    
    		int chconf = readl(&priv->regs->channel[priv->cs].chconf);
    
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    		if (flags & SPI_XFER_BEGIN) {
    
    			omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_EN);
    
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    			chconf |= OMAP3_MCSPI_CHCONF_FORCE;
    
    			omap3_spi_write_chconf(priv, chconf);
    
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    		}
    		if (flags & SPI_XFER_END) {
    			chconf &= ~OMAP3_MCSPI_CHCONF_FORCE;
    
    			omap3_spi_write_chconf(priv, chconf);
    			omap3_spi_set_enable(priv, OMAP3_MCSPI_CHCTRL_DIS);
    
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    		}
    		ret = 0;
    	} else {
    
    		if (dout != NULL && din != NULL)
    
    			ret = omap3_spi_txrx(priv, len, dout, din, flags);
    
    		else if (dout != NULL)
    
    			ret = omap3_spi_write(priv, len, dout, flags);
    
    		else if (din != NULL)
    
    			ret = omap3_spi_read(priv, len, din, flags);
    
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    	}
    	return ret;
    }
    
    
    static void _omap3_spi_set_speed(struct omap3_spi_priv *priv)
    {
    	uint32_t confr, div = 0;
    
    	confr = readl(&priv->regs->channel[priv->cs].chconf);
    
    	/* Calculate clock divisor. Valid range: 0x0 - 0xC ( /1 - /4096 ) */
    	if (priv->freq) {
    		while (div <= 0xC && (OMAP3_MCSPI_MAX_FREQ / (1 << div))
    					> priv->freq)
    			div++;
    	} else {
    		 div = 0xC;
    	}
    
    	/* set clock divisor */
    	confr &= ~OMAP3_MCSPI_CHCONF_CLKD_MASK;
    	confr |= div << 2;
    
    	omap3_spi_write_chconf(priv, confr);
    }
    
    static void _omap3_spi_set_mode(struct omap3_spi_priv *priv)
    {
    	uint32_t confr;
    
    	confr = readl(&priv->regs->channel[priv->cs].chconf);
    
    	/* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
    	 * REVISIT: this controller could support SPI_3WIRE mode.
    	 */
    	if (priv->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
    		confr &= ~(OMAP3_MCSPI_CHCONF_IS|OMAP3_MCSPI_CHCONF_DPE1);
    		confr |= OMAP3_MCSPI_CHCONF_DPE0;
    	} else {
    		confr &= ~OMAP3_MCSPI_CHCONF_DPE0;
    		confr |= OMAP3_MCSPI_CHCONF_IS|OMAP3_MCSPI_CHCONF_DPE1;
    	}
    
    	/* set SPI mode 0..3 */
    	confr &= ~(OMAP3_MCSPI_CHCONF_POL | OMAP3_MCSPI_CHCONF_PHA);
    	if (priv->mode & SPI_CPHA)
    		confr |= OMAP3_MCSPI_CHCONF_PHA;
    	if (priv->mode & SPI_CPOL)
    		confr |= OMAP3_MCSPI_CHCONF_POL;
    
    	/* set chipselect polarity; manage with FORCE */
    	if (!(priv->mode & SPI_CS_HIGH))
    		confr |= OMAP3_MCSPI_CHCONF_EPOL; /* active-low; normal */
    	else
    		confr &= ~OMAP3_MCSPI_CHCONF_EPOL;
    
    	/* Transmit & receive mode */
    	confr &= ~OMAP3_MCSPI_CHCONF_TRM_MASK;
    
    	omap3_spi_write_chconf(priv, confr);
    }
    
    static void _omap3_spi_set_wordlen(struct omap3_spi_priv *priv)
    {
    	unsigned int confr;
    
    	/* McSPI individual channel configuration */
    	confr = readl(&priv->regs->channel[priv->wordlen].chconf);
    
    	/* wordlength */
    	confr &= ~OMAP3_MCSPI_CHCONF_WL_MASK;
    	confr |= (priv->wordlen - 1) << 7;
    
    	omap3_spi_write_chconf(priv, confr);
    }
    
    static void spi_reset(struct mcspi *regs)
    {
    	unsigned int tmp;
    
    	writel(OMAP3_MCSPI_SYSCONFIG_SOFTRESET, &regs->sysconfig);
    	do {
    		tmp = readl(&regs->sysstatus);
    	} while (!(tmp & OMAP3_MCSPI_SYSSTATUS_RESETDONE));
    
    	writel(OMAP3_MCSPI_SYSCONFIG_AUTOIDLE |
    	       OMAP3_MCSPI_SYSCONFIG_ENAWAKEUP |
    	       OMAP3_MCSPI_SYSCONFIG_SMARTIDLE, &regs->sysconfig);
    
    	writel(OMAP3_MCSPI_WAKEUPENABLE_WKEN, &regs->wakeupenable);
    }
    
    static void _omap3_spi_claim_bus(struct omap3_spi_priv *priv)
    {
    	unsigned int conf;
    
    	spi_reset(priv->regs);
    
    	/*
    	 * setup when switching from (reset default) slave mode
    	 * to single-channel master mode
    	 */
    	conf = readl(&priv->regs->modulctrl);
    	conf &= ~(OMAP3_MCSPI_MODULCTRL_STEST | OMAP3_MCSPI_MODULCTRL_MS);
    	conf |= OMAP3_MCSPI_MODULCTRL_SINGLE;
    
    	writel(conf, &priv->regs->modulctrl);
    
    	_omap3_spi_set_mode(priv);
    	_omap3_spi_set_speed(priv);
    }
    
    #ifndef CONFIG_DM_SPI
    
    struct omap3_spi_slave {
    	struct spi_slave	 slave;
    	struct omap3_spi_priv   spi_priv;
    };
    
    struct omap3_spi_priv *priv;
    
    static inline struct omap3_spi_slave *to_omap3_spi(struct spi_slave *slave)
    {
    	return container_of(slave, struct omap3_spi_slave, slave);
    }
    
    void spi_init(void)
    
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    {
    
    	/* do nothing */
    
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    }
    
    
    void spi_free_slave(struct spi_slave *slave)
    
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    {
    
    	struct omap3_spi_slave *ds = to_omap3_spi(slave);
    
    	free(ds);
    }
    
    int spi_claim_bus(struct spi_slave *slave)
    {
    	_omap3_spi_claim_bus(priv);
    	_omap3_spi_set_wordlen(priv);
    	_omap3_spi_set_mode(priv);
    	_omap3_spi_set_speed(priv);
    
    	return 0;
    
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    }
    
    
    void spi_release_bus(struct spi_slave *slave)
    
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    {
    
    	/* Reset the SPI hardware */
    	spi_reset(priv->regs);
    
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    }
    
    
    struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
    				     unsigned int max_hz, unsigned int mode)
    {
    	struct omap3_spi_slave *ds;
    	struct mcspi *regs;
    
    	/*
    	 * OMAP3 McSPI (MultiChannel SPI) has 4 busses (modules)
    	 * with different number of chip selects (CS, channels):
    	 * McSPI1 has 4 CS (bus 0, cs 0 - 3)
    	 * McSPI2 has 2 CS (bus 1, cs 0 - 1)
    	 * McSPI3 has 2 CS (bus 2, cs 0 - 1)
    	 * McSPI4 has 1 CS (bus 3, cs 0)
    	 */
    
    	switch (bus) {
    	case 0:
    		 regs = (struct mcspi *)OMAP3_MCSPI1_BASE;
    		 break;
    #ifdef OMAP3_MCSPI2_BASE
    	case 1:
    		 regs = (struct mcspi *)OMAP3_MCSPI2_BASE;
    		 break;
    #endif
    #ifdef OMAP3_MCSPI3_BASE
    	case 2:
    		 regs = (struct mcspi *)OMAP3_MCSPI3_BASE;
    		 break;
    #endif
    #ifdef OMAP3_MCSPI4_BASE
    	case 3:
    		 regs = (struct mcspi *)OMAP3_MCSPI4_BASE;
    		 break;
    #endif
    	default:
    		 printf("SPI error: unsupported bus %i.  Supported busses 0 - 3\n", bus);
    		 return NULL;
    	}
    
    	if (((bus == 0) && (cs > 3)) ||
    	    ((bus == 1) && (cs > 1)) ||
    	    ((bus == 2) && (cs > 1)) ||
    	    ((bus == 3) && (cs > 0))) {
    		printf("SPI error: unsupported chip select %i on bus %i\n", cs, bus);
    		return NULL;
    	}
    
    	if (max_hz > OMAP3_MCSPI_MAX_FREQ) {
    		printf("SPI error: unsupported frequency %i Hz. Max frequency is 48 Mhz\n", max_hz);
    		return NULL;
    	}
    
    	if (mode > SPI_MODE_3) {
    		printf("SPI error: unsupported SPI mode %i\n", mode);
    		return NULL;
    	}
    
    	ds = spi_alloc_slave(struct omap3_spi_slave, bus, cs);
    	if (!ds) {
    		printf("SPI error: malloc of SPI structure failed\n");
    		return NULL;
    	}
    
    	priv = &ds->spi_priv;
    
    	priv->regs = regs;
    	priv->cs = cs;
    	priv->freq = max_hz;
    	priv->mode = mode;
    	priv->wordlen = ds->slave.wordlen;
    #ifdef CONFIG_OMAP3_SPI_D0_D1_SWAPPED
    	priv->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
    #endif
    
    	return &ds->slave;
    }
    
    int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
    	     const void *dout, void *din, unsigned long flags)
    { return _spi_xfer(priv, bitlen, dout, din, flags); }
    
    #else
    
    static int omap3_spi_claim_bus(struct udevice *dev)
    {
    	struct udevice *bus = dev->parent;
    	struct omap3_spi_priv *priv = dev_get_priv(bus);
    	struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
    
    	priv->cs = slave_plat->cs;
    	priv->mode = slave_plat->mode;
    	priv->freq = slave_plat->max_hz;
    	_omap3_spi_claim_bus(priv);
    
    	return 0;
    }
    
    static int omap3_spi_release_bus(struct udevice *dev)
    {
    	struct udevice *bus = dev->parent;
    	struct omap3_spi_priv *priv = dev_get_priv(bus);
    
    	/* Reset the SPI hardware */
    	spi_reset(priv->regs);
    
    	return 0;
    }
    
    static int omap3_spi_set_wordlen(struct udevice *dev, unsigned int wordlen)
    {
    	struct udevice *bus = dev->parent;
    	struct omap3_spi_priv *priv = dev_get_priv(bus);
    	struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
    
    	priv->cs = slave_plat->cs;
    	priv->wordlen = wordlen;
    	_omap3_spi_set_wordlen(priv);
    
    	return 0;
    }
    
    static int omap3_spi_probe(struct udevice *dev)
    {
    	struct omap3_spi_priv *priv = dev_get_priv(dev);
    	const void *blob = gd->fdt_blob;
    	int node = dev->of_offset;
    
    	priv->regs = (struct mcspi *)dev_get_addr(dev);
    	priv->pin_dir = fdtdec_get_uint(blob, node, "ti,pindir-d0-out-d1-in",
    					    MCSPI_PINDIR_D0_IN_D1_OUT);
    	priv->wordlen = SPI_DEFAULT_WORDLEN;
    	return 0;
    }
    
    static int omap3_spi_xfer(struct udevice *dev, unsigned int bitlen,
    			    const void *dout, void *din, unsigned long flags)
    {
    	struct udevice *bus = dev->parent;
    	struct omap3_spi_priv *priv = dev_get_priv(bus);
    
    	return _spi_xfer(priv, bitlen, dout, din, flags);
    }
    
    static int omap3_spi_set_speed(struct udevice *bus, unsigned int speed)
    {
    	return 0;
    }
    
    static int omap3_spi_set_mode(struct udevice *bus, uint mode)
    {
    	return 0;
    }
    
    static const struct dm_spi_ops omap3_spi_ops = {
    	.claim_bus      = omap3_spi_claim_bus,
    	.release_bus    = omap3_spi_release_bus,
    	.set_wordlen    = omap3_spi_set_wordlen,
    	.xfer	    = omap3_spi_xfer,
    	.set_speed      = omap3_spi_set_speed,
    	.set_mode	= omap3_spi_set_mode,
    	/*
    	 * cs_info is not needed, since we require all chip selects to be
    	 * in the device tree explicitly
    	 */
    };
    
    static const struct udevice_id omap3_spi_ids[] = {
    	{ .compatible = "ti,omap2-mcspi" },
    	{ .compatible = "ti,omap4-mcspi" },
    	{ }
    };
    
    U_BOOT_DRIVER(omap3_spi) = {
    	.name   = "omap3_spi",
    	.id     = UCLASS_SPI,
    	.of_match = omap3_spi_ids,
    	.probe = omap3_spi_probe,
    	.ops    = &omap3_spi_ops,
    	.priv_auto_alloc_size = sizeof(struct omap3_spi_priv),
    	.probe = omap3_spi_probe,
    };
    #endif