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author | Minkyu Kang <mk7.kang@samsung.com> | 2010-04-19 10:26:18 +0900 |
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committer | Minkyu Kang <mk7.kang@samsung.com> | 2010-04-19 10:26:18 +0900 |
commit | 83653121d7382fccfe329cb732f77f116341ef1d (patch) | |
tree | 0b1ce6764252af15dfb2614372de98a44a7ec61f /arch/ppc/cpu/mpc8260/i2c.c | |
parent | 0f1f21a345e02a68ec16f7ab9e7dc687f9276089 (diff) | |
parent | 07739bcef5da07cc4a4edef8b91014ccc332eda3 (diff) | |
download | u-boot-imx-83653121d7382fccfe329cb732f77f116341ef1d.zip u-boot-imx-83653121d7382fccfe329cb732f77f116341ef1d.tar.gz u-boot-imx-83653121d7382fccfe329cb732f77f116341ef1d.tar.bz2 |
Merge branch 'master' of git://git.denx.de/u-boot-arm
Conflicts:
cpu/arm1176/cpu.c
cpu/arm1176/start.S
cpu/arm_cortexa8/s5pc1xx/Makefile
cpu/arm_cortexa8/s5pc1xx/clock.c
drivers/serial/serial_s5p.c
include/asm-arm/arch-s5pc1xx/clk.h
include/asm-arm/arch-s5pc1xx/gpio.h
include/asm-arm/arch-s5pc1xx/uart.h
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
Diffstat (limited to 'arch/ppc/cpu/mpc8260/i2c.c')
-rw-r--r-- | arch/ppc/cpu/mpc8260/i2c.c | 785 |
1 files changed, 785 insertions, 0 deletions
diff --git a/arch/ppc/cpu/mpc8260/i2c.c b/arch/ppc/cpu/mpc8260/i2c.c new file mode 100644 index 0000000..d2bdcc2 --- /dev/null +++ b/arch/ppc/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 */ |