diff options
Diffstat (limited to 'arch/powerpc/cpu/mpc8260/i2c.c')
| -rw-r--r-- | arch/powerpc/cpu/mpc8260/i2c.c | 785 | 
1 files changed, 785 insertions, 0 deletions
| diff --git a/arch/powerpc/cpu/mpc8260/i2c.c b/arch/powerpc/cpu/mpc8260/i2c.c new file mode 100644 index 000000000..d2bdcc2d8 --- /dev/null +++ b/arch/powerpc/cpu/mpc8260/i2c.c @@ -0,0 +1,785 @@ +/* + * (C) Copyright 2000 + * Paolo Scaffardi, AIRVENT SAM s.p.a - RIMINI(ITALY), arsenio@tin.it + * + * (C) Copyright 2000 Sysgo Real-Time Solutions, GmbH <www.elinos.com> + * Marius Groeger <mgroeger@sysgo.de> + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <common.h> + +#if defined(CONFIG_HARD_I2C) + +#include <asm/cpm_8260.h> +#include <i2c.h> + +/* define to enable debug messages */ +#undef  DEBUG_I2C + +DECLARE_GLOBAL_DATA_PTR; + +#if defined(CONFIG_I2C_MULTI_BUS) +static unsigned int i2c_bus_num __attribute__ ((section (".data"))) = 0; +#endif /* CONFIG_I2C_MULTI_BUS */ + +/* uSec to wait between polls of the i2c */ +#define DELAY_US	100 +/* uSec to wait for the CPM to start processing the buffer */ +#define START_DELAY_US	1000 + +/* + * tx/rx per-byte timeout: we delay DELAY_US uSec between polls so the + * timeout will be (tx_length + rx_length) * DELAY_US * TOUT_LOOP + */ +#define TOUT_LOOP 5 + +/*----------------------------------------------------------------------- + * Set default values + */ +#ifndef	CONFIG_SYS_I2C_SPEED +#define	CONFIG_SYS_I2C_SPEED	50000 +#endif + +/*----------------------------------------------------------------------- + */ + +typedef void (*i2c_ecb_t)(int, int, void *);    /* error callback function */ + +/* This structure keeps track of the bd and buffer space usage. */ +typedef struct i2c_state { +	int		rx_idx;		/* index   to next free Rx BD */ +	int		tx_idx;		/* index   to next free Tx BD */ +	void		*rxbd;		/* pointer to next free Rx BD */ +	void		*txbd;		/* pointer to next free Tx BD */ +	int		tx_space;	/* number  of Tx bytes left   */ +	unsigned char	*tx_buf;	/* pointer to free Tx area    */ +	i2c_ecb_t	err_cb;		/* error callback function    */ +	void		*cb_data;	/* private data to be passed  */ +} i2c_state_t; + +/* flags for i2c_send() and i2c_receive() */ +#define	I2CF_ENABLE_SECONDARY	0x01	/* secondary_address is valid	*/ +#define	I2CF_START_COND		0x02	/* tx: generate start condition	*/ +#define I2CF_STOP_COND		0x04	/* tx: generate stop  condition	*/ + +/* return codes */ +#define I2CERR_NO_BUFFERS	1	/* no more BDs or buffer space	*/ +#define I2CERR_MSG_TOO_LONG	2	/* tried to send/receive to much data   */ +#define I2CERR_TIMEOUT		3	/* timeout in i2c_doio()	*/ +#define I2CERR_QUEUE_EMPTY	4	/* i2c_doio called without send/receive */ +#define I2CERR_IO_ERROR		5	/* had an error during comms	*/ + +/* error callback flags */ +#define I2CECB_RX_ERR		0x10	/* this is a receive error	*/ +#define     I2CECB_RX_OV	0x02	/* receive overrun error	*/ +#define     I2CECB_RX_MASK	0x0f	/* mask for error bits		*/ +#define I2CECB_TX_ERR		0x20	/* this is a transmit error	*/ +#define     I2CECB_TX_CL	0x01	/* transmit collision error	*/ +#define     I2CECB_TX_UN	0x02	/* transmit underflow error	*/ +#define     I2CECB_TX_NAK	0x04	/* transmit no ack error	*/ +#define     I2CECB_TX_MASK	0x0f	/* mask for error bits		*/ +#define I2CECB_TIMEOUT		0x40	/* this is a timeout error	*/ + +#define ERROR_I2C_NONE		0 +#define ERROR_I2C_LENGTH	1 + +#define I2C_WRITE_BIT		0x00 +#define I2C_READ_BIT		0x01 + +#define I2C_RXTX_LEN	128	/* maximum tx/rx buffer length */ + + +#define NUM_RX_BDS 4 +#define NUM_TX_BDS 4 +#define MAX_TX_SPACE 256 + +typedef struct I2C_BD +{ +  unsigned short status; +  unsigned short length; +  unsigned char *addr; +} I2C_BD; +#define BD_I2C_TX_START 0x0400  /* special status for i2c: Start condition */ + +#define BD_I2C_TX_CL	0x0001	/* collision error */ +#define BD_I2C_TX_UN	0x0002	/* underflow error */ +#define BD_I2C_TX_NAK	0x0004	/* no acknowledge error */ +#define BD_I2C_TX_ERR	(BD_I2C_TX_NAK|BD_I2C_TX_UN|BD_I2C_TX_CL) + +#define BD_I2C_RX_ERR	BD_SC_OV + +#ifdef DEBUG_I2C +#define PRINTD(x) printf x +#else +#define PRINTD(x) +#endif + +/* + * Returns the best value of I2BRG to meet desired clock speed of I2C with + * input parameters (clock speed, filter, and predivider value). + * It returns computer speed value and the difference between it and desired + * speed. + */ +static inline int +i2c_roundrate(int hz, int speed, int filter, int modval, +		int *brgval, int *totspeed) +{ +    int moddiv = 1 << (5-(modval & 3)), brgdiv, div; + +    PRINTD(("\t[I2C] trying hz=%d, speed=%d, filter=%d, modval=%d\n", +	hz, speed, filter, modval)); + +    div = moddiv * speed; +    brgdiv = (hz + div - 1) / div; + +    PRINTD(("\t\tmoddiv=%d, brgdiv=%d\n", moddiv, brgdiv)); + +    *brgval = ((brgdiv + 1) / 2) - 3 - (2*filter); + +    if ((*brgval < 0) || (*brgval > 255)) { +	  PRINTD(("\t\trejected brgval=%d\n", *brgval)); +	  return -1; +    } + +    brgdiv = 2 * (*brgval + 3 + (2 * filter)); +    div = moddiv * brgdiv ; +    *totspeed = hz / div; + +    PRINTD(("\t\taccepted brgval=%d, totspeed=%d\n", *brgval, *totspeed)); + +    return  0; +} + +/* + * Sets the I2C clock predivider and divider to meet required clock speed. + */ +static int i2c_setrate(int hz, int speed) +{ +    immap_t	*immap = (immap_t *)CONFIG_SYS_IMMR ; +    volatile i2c8260_t *i2c = (i2c8260_t *)&immap->im_i2c; +    int brgval, +	  modval,	/* 0-3 */ +	  bestspeed_diff = speed, +	  bestspeed_brgval=0, +	  bestspeed_modval=0, +	  bestspeed_filter=0, +	  totspeed, +	  filter = 0; /* Use this fixed value */ + +	for (modval = 0; modval < 4; modval++) +	{ +		if (i2c_roundrate (hz, speed, filter, modval, &brgval, &totspeed) == 0) +		{ +			int diff = speed - totspeed ; + +			if ((diff >= 0) && (diff < bestspeed_diff)) +			{ +				bestspeed_diff	= diff ; +				bestspeed_modval	= modval; +				bestspeed_brgval	= brgval; +				bestspeed_filter	= filter; +			} +		} +	} + +    PRINTD(("[I2C] Best is:\n")); +    PRINTD(("[I2C] CPU=%dhz RATE=%d F=%d I2MOD=%08x I2BRG=%08x DIFF=%dhz\n", +		   hz, speed, +		   bestspeed_filter, bestspeed_modval, bestspeed_brgval, +		   bestspeed_diff)); + +    i2c->i2c_i2mod |= ((bestspeed_modval & 3) << 1) | (bestspeed_filter << 3); +    i2c->i2c_i2brg = bestspeed_brgval & 0xff; + +    PRINTD(("[I2C] i2mod=%08x i2brg=%08x\n", i2c->i2c_i2mod, i2c->i2c_i2brg)); + +    return 1 ; +} + +void i2c_init(int speed, int slaveadd) +{ +	volatile immap_t *immap = (immap_t *)CONFIG_SYS_IMMR ; +	volatile cpm8260_t *cp = (cpm8260_t *)&immap->im_cpm; +	volatile i2c8260_t *i2c	= (i2c8260_t *)&immap->im_i2c; +	volatile iic_t *iip; +	ulong rbase, tbase; +	volatile I2C_BD *rxbd, *txbd; +	uint dpaddr; + +#ifdef CONFIG_SYS_I2C_INIT_BOARD +	/* call board specific i2c bus reset routine before accessing the   */ +	/* environment, which might be in a chip on that bus. For details   */ +	/* about this problem see doc/I2C_Edge_Conditions.                  */ +	i2c_init_board(); +#endif + +	dpaddr = *((unsigned short*)(&immap->im_dprambase[PROFF_I2C_BASE])); +	if (dpaddr == 0) { +	    /* need to allocate dual port ram */ +	    dpaddr = m8260_cpm_dpalloc(64 + +		(NUM_RX_BDS * sizeof(I2C_BD)) + (NUM_TX_BDS * sizeof(I2C_BD)) + +		MAX_TX_SPACE, 64); +	    *((unsigned short*)(&immap->im_dprambase[PROFF_I2C_BASE])) = dpaddr; +	} + +	/* +	 * initialise data in dual port ram: +	 * +	 *	  dpaddr -> parameter ram (64 bytes) +	 *         rbase -> rx BD         (NUM_RX_BDS * sizeof(I2C_BD) bytes) +	 *         tbase -> tx BD         (NUM_TX_BDS * sizeof(I2C_BD) bytes) +	 *                  tx buffer     (MAX_TX_SPACE bytes) +	 */ + +	iip = (iic_t *)&immap->im_dprambase[dpaddr]; +	memset((void*)iip, 0, sizeof(iic_t)); + +	rbase = dpaddr + 64; +	tbase = rbase + NUM_RX_BDS * sizeof(I2C_BD); + +	/* Disable interrupts */ +	i2c->i2c_i2mod = 0x00; +	i2c->i2c_i2cmr = 0x00; +	i2c->i2c_i2cer = 0xff; +	i2c->i2c_i2add = slaveadd; + +	/* +	 * Set the I2C BRG Clock division factor from desired i2c rate +	 * and current CPU rate (we assume sccr dfbgr field is 0; +	 * divide BRGCLK by 1) +	 */ +	PRINTD(("[I2C] Setting rate...\n")); +	i2c_setrate (gd->brg_clk, CONFIG_SYS_I2C_SPEED) ; + +	/* Set I2C controller in master mode */ +	i2c->i2c_i2com = 0x01; + +	/* Initialize Tx/Rx parameters */ +	iip->iic_rbase = rbase; +	iip->iic_tbase = tbase; +	rxbd = (I2C_BD *)((unsigned char *)&immap->im_dprambase[iip->iic_rbase]); +	txbd = (I2C_BD *)((unsigned char *)&immap->im_dprambase[iip->iic_tbase]); + +	PRINTD(("[I2C] rbase = %04x\n", iip->iic_rbase)); +	PRINTD(("[I2C] tbase = %04x\n", iip->iic_tbase)); +	PRINTD(("[I2C] rxbd = %08x\n", (int)rxbd)); +	PRINTD(("[I2C] txbd = %08x\n", (int)txbd)); + +	/* Set big endian byte order */ +	iip->iic_tfcr = 0x10; +	iip->iic_rfcr = 0x10; + +	/* Set maximum receive size. */ +	iip->iic_mrblr = I2C_RXTX_LEN; + +    cp->cp_cpcr = mk_cr_cmd(CPM_CR_I2C_PAGE, +							CPM_CR_I2C_SBLOCK, +							0x00, +							CPM_CR_INIT_TRX) | CPM_CR_FLG; +    do { +		__asm__ __volatile__ ("eieio"); +    } while (cp->cp_cpcr & CPM_CR_FLG); + +	/* Clear events and interrupts */ +	i2c->i2c_i2cer = 0xff; +	i2c->i2c_i2cmr = 0x00; +} + +static +void i2c_newio(i2c_state_t *state) +{ +	volatile immap_t *immap = (immap_t *)CONFIG_SYS_IMMR ; +	volatile iic_t *iip; +	uint dpaddr; + +	PRINTD(("[I2C] i2c_newio\n")); + +	dpaddr = *((unsigned short*)(&immap->im_dprambase[PROFF_I2C_BASE])); +	iip = (iic_t *)&immap->im_dprambase[dpaddr]; +	state->rx_idx = 0; +	state->tx_idx = 0; +	state->rxbd = (void*)&immap->im_dprambase[iip->iic_rbase]; +	state->txbd = (void*)&immap->im_dprambase[iip->iic_tbase]; +	state->tx_space = MAX_TX_SPACE; +	state->tx_buf = (uchar*)state->txbd + NUM_TX_BDS * sizeof(I2C_BD); +	state->err_cb = NULL; +	state->cb_data = NULL; + +	PRINTD(("[I2C] rxbd = %08x\n", (int)state->rxbd)); +	PRINTD(("[I2C] txbd = %08x\n", (int)state->txbd)); +	PRINTD(("[I2C] tx_buf = %08x\n", (int)state->tx_buf)); + +	/* clear the buffer memory */ +	memset((char *)state->tx_buf, 0, MAX_TX_SPACE); +} + +static +int i2c_send(i2c_state_t *state, +			 unsigned char address, +			 unsigned char secondary_address, +			 unsigned int flags, +			 unsigned short size, +			 unsigned char *dataout) +{ +	volatile I2C_BD *txbd; +	int i,j; + +	PRINTD(("[I2C] i2c_send add=%02d sec=%02d flag=%02d size=%d\n", +			address, secondary_address, flags, size)); + +	/* trying to send message larger than BD */ +	if (size > I2C_RXTX_LEN) +	  return I2CERR_MSG_TOO_LONG; + +	/* no more free bds */ +	if (state->tx_idx >= NUM_TX_BDS || state->tx_space < (2 + size)) +	  return I2CERR_NO_BUFFERS; + +	txbd = (I2C_BD *)state->txbd; +	txbd->addr = state->tx_buf; + +	PRINTD(("[I2C] txbd = %08x\n", (int)txbd)); + +    if (flags & I2CF_START_COND) +    { +	PRINTD(("[I2C] Formatting addresses...\n")); +	if (flags & I2CF_ENABLE_SECONDARY) +	{ +		txbd->length = size + 2;  /* Length of message plus dest addresses */ +		txbd->addr[0] = address << 1; +		txbd->addr[1] = secondary_address; +		i = 2; +	} +	else +	{ +		txbd->length = size + 1;  /* Length of message plus dest address */ +		txbd->addr[0] = address << 1;  /* Write destination address to BD */ +		i = 1; +	} +    } +    else +    { +	txbd->length = size;  /* Length of message */ +	i = 0; +    } + +	/* set up txbd */ +	txbd->status = BD_SC_READY; +	if (flags & I2CF_START_COND) +	  txbd->status |= BD_I2C_TX_START; +	if (flags & I2CF_STOP_COND) +	  txbd->status |= BD_SC_LAST | BD_SC_WRAP; + +	/* Copy data to send into buffer */ +	PRINTD(("[I2C] copy data...\n")); +	for(j = 0; j < size; i++, j++) +	  txbd->addr[i] = dataout[j]; + +	PRINTD(("[I2C] txbd: length=0x%04x status=0x%04x addr[0]=0x%02x addr[1]=0x%02x\n", +		   txbd->length, +		   txbd->status, +		   txbd->addr[0], +		   txbd->addr[1])); + +	/* advance state */ +	state->tx_buf += txbd->length; +	state->tx_space -= txbd->length; +	state->tx_idx++; +	state->txbd = (void*)(txbd + 1); + +	return 0; +} + +static +int i2c_receive(i2c_state_t *state, +				unsigned char address, +				unsigned char secondary_address, +				unsigned int flags, +				unsigned short size_to_expect, +				unsigned char *datain) +{ +	volatile I2C_BD *rxbd, *txbd; + +	PRINTD(("[I2C] i2c_receive %02d %02d %02d\n", address, secondary_address, flags)); + +	/* Expected to receive too much */ +	if (size_to_expect > I2C_RXTX_LEN) +	  return I2CERR_MSG_TOO_LONG; + +	/* no more free bds */ +	if (state->tx_idx >= NUM_TX_BDS || state->rx_idx >= NUM_RX_BDS +		 || state->tx_space < 2) +	  return I2CERR_NO_BUFFERS; + +	rxbd = (I2C_BD *)state->rxbd; +	txbd = (I2C_BD *)state->txbd; + +	PRINTD(("[I2C] rxbd = %08x\n", (int)rxbd)); +	PRINTD(("[I2C] txbd = %08x\n", (int)txbd)); + +	txbd->addr = state->tx_buf; + +	/* set up TXBD for destination address */ +	if (flags & I2CF_ENABLE_SECONDARY) +	{ +		txbd->length = 2; +		txbd->addr[0] = address << 1;   /* Write data */ +		txbd->addr[1] = secondary_address;  /* Internal address */ +		txbd->status = BD_SC_READY; +	} +	else +	{ +		txbd->length = 1 + size_to_expect; +		txbd->addr[0] = (address << 1) | 0x01; +		txbd->status = BD_SC_READY; +		memset(&txbd->addr[1], 0, txbd->length); +	} + +	/* set up rxbd for reception */ +	rxbd->status = BD_SC_EMPTY; +	rxbd->length = size_to_expect; +	rxbd->addr = datain; + +	txbd->status |= BD_I2C_TX_START; +	if (flags & I2CF_STOP_COND) +	{ +		txbd->status |= BD_SC_LAST | BD_SC_WRAP; +		rxbd->status |= BD_SC_WRAP; +	} + +	PRINTD(("[I2C] txbd: length=0x%04x status=0x%04x addr[0]=0x%02x addr[1]=0x%02x\n", +		   txbd->length, +		   txbd->status, +		   txbd->addr[0], +		   txbd->addr[1])); +	PRINTD(("[I2C] rxbd: length=0x%04x status=0x%04x addr[0]=0x%02x addr[1]=0x%02x\n", +		   rxbd->length, +		   rxbd->status, +		   rxbd->addr[0], +		   rxbd->addr[1])); + +	/* advance state */ +	state->tx_buf += txbd->length; +	state->tx_space -= txbd->length; +	state->tx_idx++; +	state->txbd = (void*)(txbd + 1); +	state->rx_idx++; +	state->rxbd = (void*)(rxbd + 1); + +	return 0; +} + + +static +int i2c_doio(i2c_state_t *state) +{ +	volatile immap_t *immap = (immap_t *)CONFIG_SYS_IMMR ; +	volatile iic_t *iip; +	volatile i2c8260_t *i2c	= (i2c8260_t *)&immap->im_i2c; +	volatile I2C_BD *txbd, *rxbd; +	int  n, i, b, rxcnt = 0, rxtimeo = 0, txcnt = 0, txtimeo = 0, rc = 0; +	uint dpaddr; + +	PRINTD(("[I2C] i2c_doio\n")); + +	if (state->tx_idx <= 0 && state->rx_idx <= 0) { +		PRINTD(("[I2C] No I/O is queued\n")); +		return I2CERR_QUEUE_EMPTY; +	} + +	dpaddr = *((unsigned short*)(&immap->im_dprambase[PROFF_I2C_BASE])); +	iip = (iic_t *)&immap->im_dprambase[dpaddr]; +	iip->iic_rbptr = iip->iic_rbase; +	iip->iic_tbptr = iip->iic_tbase; + +	/* Enable I2C */ +	PRINTD(("[I2C] Enabling I2C...\n")); +	i2c->i2c_i2mod |= 0x01; + +	/* Begin transmission */ +	i2c->i2c_i2com |= 0x80; + +	/* Loop until transmit & receive completed */ + +	if ((n = state->tx_idx) > 0) { + +		txbd = ((I2C_BD*)state->txbd) - n; +		for (i = 0; i < n; i++) { +			txtimeo += TOUT_LOOP * txbd->length; +			txbd++; +		} + +		txbd--; /* wait until last in list is done */ + +		PRINTD(("[I2C] Transmitting...(txbd=0x%08lx)\n", (ulong)txbd)); + +		udelay(START_DELAY_US);	/* give it time to start */ +		while((txbd->status & BD_SC_READY) && (++txcnt < txtimeo)) { +			udelay(DELAY_US); +			if (ctrlc()) +				return (-1); +			__asm__ __volatile__ ("eieio"); +		} +	} + +	if (txcnt < txtimeo && (n = state->rx_idx) > 0) { + +		rxbd = ((I2C_BD*)state->rxbd) - n; +		for (i = 0; i < n; i++) { +			rxtimeo += TOUT_LOOP * rxbd->length; +			rxbd++; +		} + +		rxbd--; /* wait until last in list is done */ + +		PRINTD(("[I2C] Receiving...(rxbd=0x%08lx)\n", (ulong)rxbd)); + +		udelay(START_DELAY_US);	/* give it time to start */ +		while((rxbd->status & BD_SC_EMPTY) && (++rxcnt < rxtimeo)) { +			udelay(DELAY_US); +			if (ctrlc()) +				return (-1); +			__asm__ __volatile__ ("eieio"); +		} +	} + +	/* Turn off I2C */ +	i2c->i2c_i2mod &= ~0x01; + +	if ((n = state->tx_idx) > 0) { +		for (i = 0; i < n; i++) { +			txbd = ((I2C_BD*)state->txbd) - (n - i); +			if ((b = txbd->status & BD_I2C_TX_ERR) != 0) { +				if (state->err_cb != NULL) +					(*state->err_cb)(I2CECB_TX_ERR|b, i, +						state->cb_data); +				if (rc == 0) +					rc = I2CERR_IO_ERROR; +			} +		} +	} + +	if ((n = state->rx_idx) > 0) { +		for (i = 0; i < n; i++) { +			rxbd = ((I2C_BD*)state->rxbd) - (n - i); +			if ((b = rxbd->status & BD_I2C_RX_ERR) != 0) { +				if (state->err_cb != NULL) +					(*state->err_cb)(I2CECB_RX_ERR|b, i, +						state->cb_data); +				if (rc == 0) +					rc = I2CERR_IO_ERROR; +			} +		} +	} + +	if ((txtimeo > 0 && txcnt >= txtimeo) || \ +	    (rxtimeo > 0 && rxcnt >= rxtimeo)) { +		if (state->err_cb != NULL) +			(*state->err_cb)(I2CECB_TIMEOUT, -1, state->cb_data); +		if (rc == 0) +			rc = I2CERR_TIMEOUT; +	} + +	return (rc); +} + +static void +i2c_probe_callback(int flags, int xnum, void *data) +{ +	/* +	 * the only acceptable errors are a transmit NAK or a receive +	 * overrun - tx NAK means the device does not exist, rx OV +	 * means the device must have responded to the slave address +	 * even though the transfer failed +	 */ +	if (flags == (I2CECB_TX_ERR|I2CECB_TX_NAK)) +		*(int *)data |= 1; +	if (flags == (I2CECB_RX_ERR|I2CECB_RX_OV)) +		*(int *)data |= 2; +} + +int +i2c_probe(uchar chip) +{ +	i2c_state_t state; +	int rc, err_flag; +	uchar buf[1]; + +	i2c_newio(&state); + +	state.err_cb = i2c_probe_callback; +	state.cb_data = (void *) &err_flag; +	err_flag = 0; + +	rc = i2c_receive(&state, chip, 0, I2CF_START_COND|I2CF_STOP_COND, 1, buf); + +	if (rc != 0) +		return (rc);	/* probe failed */ + +	rc = i2c_doio(&state); + +	if (rc == 0) +		return (0);	/* device exists - read succeeded */ + +	if (rc == I2CERR_TIMEOUT) +		return (-1);	/* device does not exist - timeout */ + +	if (rc != I2CERR_IO_ERROR || err_flag == 0) +		return (rc);	/* probe failed */ + +	if (err_flag & 1) +		return (-1);	/* device does not exist - had transmit NAK */ + +	return (0);	/* device exists - had receive overrun */ +} + + +int +i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len) +{ +	i2c_state_t state; +	uchar xaddr[4]; +	int rc; + +	xaddr[0] = (addr >> 24) & 0xFF; +	xaddr[1] = (addr >> 16) & 0xFF; +	xaddr[2] = (addr >>  8) & 0xFF; +	xaddr[3] =  addr        & 0xFF; + +#ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW +	 /* +	  * EEPROM chips that implement "address overflow" are ones +	  * like Catalyst 24WC04/08/16 which has 9/10/11 bits of address +	  * and the extra bits end up in the "chip address" bit slots. +	  * This makes a 24WC08 (1Kbyte) chip look like four 256 byte +	  * chips. +	  * +	  * Note that we consider the length of the address field to still +	  * be one byte because the extra address bits are hidden in the +	  * chip address. +	  */ +	chip |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW); +#endif + +	i2c_newio(&state); + +	rc = i2c_send(&state, chip, 0, I2CF_START_COND, alen, &xaddr[4-alen]); +	if (rc != 0) { +		printf("i2c_read: i2c_send failed (%d)\n", rc); +		return 1; +	} + +	rc = i2c_receive(&state, chip, 0, I2CF_STOP_COND, len, buffer); +	if (rc != 0) { +		printf("i2c_read: i2c_receive failed (%d)\n", rc); +		return 1; +	} + +	rc = i2c_doio(&state); +	if (rc != 0) { +		printf("i2c_read: i2c_doio failed (%d)\n", rc); +		return 1; +	} +	return 0; +} + +int +i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len) +{ +	i2c_state_t state; +	uchar xaddr[4]; +	int rc; + +	xaddr[0] = (addr >> 24) & 0xFF; +	xaddr[1] = (addr >> 16) & 0xFF; +	xaddr[2] = (addr >>  8) & 0xFF; +	xaddr[3] =  addr        & 0xFF; + +#ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW +	 /* +	  * EEPROM chips that implement "address overflow" are ones +	  * like Catalyst 24WC04/08/16 which has 9/10/11 bits of address +	  * and the extra bits end up in the "chip address" bit slots. +	  * This makes a 24WC08 (1Kbyte) chip look like four 256 byte +	  * chips. +	  * +	  * Note that we consider the length of the address field to still +	  * be one byte because the extra address bits are hidden in the +	  * chip address. +	  */ +	chip |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW); +#endif + +	i2c_newio(&state); + +	rc = i2c_send(&state, chip, 0, I2CF_START_COND, alen, &xaddr[4-alen]); +	if (rc != 0) { +		printf("i2c_write: first i2c_send failed (%d)\n", rc); +		return 1; +	} + +	rc = i2c_send(&state, 0, 0, I2CF_STOP_COND, len, buffer); +	if (rc != 0) { +		printf("i2c_write: second i2c_send failed (%d)\n", rc); +		return 1; +	} + +	rc = i2c_doio(&state); +	if (rc != 0) { +		printf("i2c_write: i2c_doio failed (%d)\n", rc); +		return 1; +	} +	return 0; +} + +#if defined(CONFIG_I2C_MULTI_BUS) +/* + * Functions for multiple I2C bus handling + */ +unsigned int i2c_get_bus_num(void) +{ +	return i2c_bus_num; +} + +int i2c_set_bus_num(unsigned int bus) +{ +#if defined(CONFIG_I2C_MUX) +	if (bus < CONFIG_SYS_MAX_I2C_BUS) { +		i2c_bus_num = bus; +	} else { +		int	ret; + +		ret = i2x_mux_select_mux(bus); +		if (ret == 0) +			i2c_bus_num = bus; +		else +			return ret; +	} +#else +	if (bus >= CONFIG_SYS_MAX_I2C_BUS) +		return -1; +	i2c_bus_num = bus; +#endif +	return 0; +} + +#endif	/* CONFIG_I2C_MULTI_BUS */ +#endif	/* CONFIG_HARD_I2C */ |