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authorWolfgang Denk <wd@denx.de>2008-09-01 00:16:29 +0200
committerWolfgang Denk <wd@denx.de>2008-09-01 00:16:29 +0200
commite99e9575bbeba1b7c48e046547cae065ec0071de (patch)
treec08553c4d06725bd6013a46068df0059c5b49a00 /common/soft_i2c.c
parenta13b2d937941f6b525abfcfad96c034f94421188 (diff)
parent08ab4e1780fa63c88dd5a5ab52f4ff4ed1ee1878 (diff)
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Merge branch 'Makefile' of git://git.denx.de/u-boot-arm
Diffstat (limited to 'common/soft_i2c.c')
-rw-r--r--common/soft_i2c.c423
1 files changed, 0 insertions, 423 deletions
diff --git a/common/soft_i2c.c b/common/soft_i2c.c
deleted file mode 100644
index 23db2ee..0000000
--- a/common/soft_i2c.c
+++ /dev/null
@@ -1,423 +0,0 @@
-/*
- * (C) Copyright 2001, 2002
- * Wolfgang Denk, DENX Software Engineering, wd@denx.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
- *
- * This has been changed substantially by Gerald Van Baren, Custom IDEAS,
- * vanbaren@cideas.com. It was heavily influenced by LiMon, written by
- * Neil Russell.
- */
-
-#include <common.h>
-#ifdef CONFIG_MPC8260 /* only valid for MPC8260 */
-#include <ioports.h>
-#endif
-#ifdef CONFIG_AT91RM9200 /* need this for the at91rm9200 */
-#include <asm/io.h>
-#include <asm/arch/hardware.h>
-#endif
-#ifdef CONFIG_IXP425 /* only valid for IXP425 */
-#include <asm/arch/ixp425.h>
-#endif
-#ifdef CONFIG_LPC2292
-#include <asm/arch/hardware.h>
-#endif
-#include <i2c.h>
-
-/* #define DEBUG_I2C */
-
-#ifdef DEBUG_I2C
-DECLARE_GLOBAL_DATA_PTR;
-#endif
-
-
-/*-----------------------------------------------------------------------
- * Definitions
- */
-
-#define RETRIES 0
-
-
-#define I2C_ACK 0 /* PD_SDA level to ack a byte */
-#define I2C_NOACK 1 /* PD_SDA level to noack a byte */
-
-
-#ifdef DEBUG_I2C
-#define PRINTD(fmt,args...) do { \
- if (gd->have_console) \
- printf (fmt ,##args); \
- } while (0)
-#else
-#define PRINTD(fmt,args...)
-#endif
-
-/*-----------------------------------------------------------------------
- * Local functions
- */
-static void send_reset (void);
-static void send_start (void);
-static void send_stop (void);
-static void send_ack (int);
-static int write_byte (uchar byte);
-static uchar read_byte (int);
-
-
-/*-----------------------------------------------------------------------
- * Send a reset sequence consisting of 9 clocks with the data signal high
- * to clock any confused device back into an idle state. Also send a
- * <stop> at the end of the sequence for belts & suspenders.
- */
-static void send_reset(void)
-{
-#ifdef CONFIG_MPC8260
- volatile ioport_t *iop = ioport_addr((immap_t *)CFG_IMMR, I2C_PORT);
-#endif
-#ifdef CONFIG_8xx
- volatile immap_t *immr = (immap_t *)CFG_IMMR;
-#endif
- int j;
-
- I2C_SCL(1);
- I2C_SDA(1);
-#ifdef I2C_INIT
- I2C_INIT;
-#endif
- I2C_TRISTATE;
- for(j = 0; j < 9; j++) {
- I2C_SCL(0);
- I2C_DELAY;
- I2C_DELAY;
- I2C_SCL(1);
- I2C_DELAY;
- I2C_DELAY;
- }
- send_stop();
- I2C_TRISTATE;
-}
-
-/*-----------------------------------------------------------------------
- * START: High -> Low on SDA while SCL is High
- */
-static void send_start(void)
-{
-#ifdef CONFIG_MPC8260
- volatile ioport_t *iop = ioport_addr((immap_t *)CFG_IMMR, I2C_PORT);
-#endif
-#ifdef CONFIG_8xx
- volatile immap_t *immr = (immap_t *)CFG_IMMR;
-#endif
-
- I2C_DELAY;
- I2C_SDA(1);
- I2C_ACTIVE;
- I2C_DELAY;
- I2C_SCL(1);
- I2C_DELAY;
- I2C_SDA(0);
- I2C_DELAY;
-}
-
-/*-----------------------------------------------------------------------
- * STOP: Low -> High on SDA while SCL is High
- */
-static void send_stop(void)
-{
-#ifdef CONFIG_MPC8260
- volatile ioport_t *iop = ioport_addr((immap_t *)CFG_IMMR, I2C_PORT);
-#endif
-#ifdef CONFIG_8xx
- volatile immap_t *immr = (immap_t *)CFG_IMMR;
-#endif
-
- I2C_SCL(0);
- I2C_DELAY;
- I2C_SDA(0);
- I2C_ACTIVE;
- I2C_DELAY;
- I2C_SCL(1);
- I2C_DELAY;
- I2C_SDA(1);
- I2C_DELAY;
- I2C_TRISTATE;
-}
-
-
-/*-----------------------------------------------------------------------
- * ack should be I2C_ACK or I2C_NOACK
- */
-static void send_ack(int ack)
-{
-#ifdef CONFIG_MPC8260
- volatile ioport_t *iop = ioport_addr((immap_t *)CFG_IMMR, I2C_PORT);
-#endif
-#ifdef CONFIG_8xx
- volatile immap_t *immr = (immap_t *)CFG_IMMR;
-#endif
-
- I2C_SCL(0);
- I2C_DELAY;
- I2C_ACTIVE;
- I2C_SDA(ack);
- I2C_DELAY;
- I2C_SCL(1);
- I2C_DELAY;
- I2C_DELAY;
- I2C_SCL(0);
- I2C_DELAY;
-}
-
-
-/*-----------------------------------------------------------------------
- * Send 8 bits and look for an acknowledgement.
- */
-static int write_byte(uchar data)
-{
-#ifdef CONFIG_MPC8260
- volatile ioport_t *iop = ioport_addr((immap_t *)CFG_IMMR, I2C_PORT);
-#endif
-#ifdef CONFIG_8xx
- volatile immap_t *immr = (immap_t *)CFG_IMMR;
-#endif
- int j;
- int nack;
-
- I2C_ACTIVE;
- for(j = 0; j < 8; j++) {
- I2C_SCL(0);
- I2C_DELAY;
- I2C_SDA(data & 0x80);
- I2C_DELAY;
- I2C_SCL(1);
- I2C_DELAY;
- I2C_DELAY;
-
- data <<= 1;
- }
-
- /*
- * Look for an <ACK>(negative logic) and return it.
- */
- I2C_SCL(0);
- I2C_DELAY;
- I2C_SDA(1);
- I2C_TRISTATE;
- I2C_DELAY;
- I2C_SCL(1);
- I2C_DELAY;
- I2C_DELAY;
- nack = I2C_READ;
- I2C_SCL(0);
- I2C_DELAY;
- I2C_ACTIVE;
-
- return(nack); /* not a nack is an ack */
-}
-
-
-/*-----------------------------------------------------------------------
- * if ack == I2C_ACK, ACK the byte so can continue reading, else
- * send I2C_NOACK to end the read.
- */
-static uchar read_byte(int ack)
-{
-#ifdef CONFIG_MPC8260
- volatile ioport_t *iop = ioport_addr((immap_t *)CFG_IMMR, I2C_PORT);
-#endif
-#ifdef CONFIG_8xx
- volatile immap_t *immr = (immap_t *)CFG_IMMR;
-#endif
- int data;
- int j;
-
- /*
- * Read 8 bits, MSB first.
- */
- I2C_TRISTATE;
- I2C_SDA(1);
- data = 0;
- for(j = 0; j < 8; j++) {
- I2C_SCL(0);
- I2C_DELAY;
- I2C_SCL(1);
- I2C_DELAY;
- data <<= 1;
- data |= I2C_READ;
- I2C_DELAY;
- }
- send_ack(ack);
-
- return(data);
-}
-
-/*=====================================================================*/
-/* Public Functions */
-/*=====================================================================*/
-
-/*-----------------------------------------------------------------------
- * Initialization
- */
-void i2c_init (int speed, int slaveaddr)
-{
- /*
- * WARNING: Do NOT save speed in a static variable: if the
- * I2C routines are called before RAM is initialized (to read
- * the DIMM SPD, for instance), RAM won't be usable and your
- * system will crash.
- */
- send_reset ();
-}
-
-/*-----------------------------------------------------------------------
- * Probe to see if a chip is present. Also good for checking for the
- * completion of EEPROM writes since the chip stops responding until
- * the write completes (typically 10mSec).
- */
-int i2c_probe(uchar addr)
-{
- int rc;
-
- /*
- * perform 1 byte write transaction with just address byte
- * (fake write)
- */
- send_start();
- rc = write_byte ((addr << 1) | 0);
- send_stop();
-
- return (rc ? 1 : 0);
-}
-
-/*-----------------------------------------------------------------------
- * Read bytes
- */
-int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
-{
- int shift;
- PRINTD("i2c_read: chip %02X addr %02X alen %d buffer %p len %d\n",
- chip, addr, alen, buffer, len);
-
-#ifdef CFG_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)) & CFG_I2C_EEPROM_ADDR_OVERFLOW);
-
- PRINTD("i2c_read: fix addr_overflow: chip %02X addr %02X\n",
- chip, addr);
-#endif
-
- /*
- * Do the addressing portion of a write cycle to set the
- * chip's address pointer. If the address length is zero,
- * don't do the normal write cycle to set the address pointer,
- * there is no address pointer in this chip.
- */
- send_start();
- if(alen > 0) {
- if(write_byte(chip << 1)) { /* write cycle */
- send_stop();
- PRINTD("i2c_read, no chip responded %02X\n", chip);
- return(1);
- }
- shift = (alen-1) * 8;
- while(alen-- > 0) {
- if(write_byte(addr >> shift)) {
- PRINTD("i2c_read, address not <ACK>ed\n");
- return(1);
- }
- shift -= 8;
- }
- send_stop(); /* reportedly some chips need a full stop */
- send_start();
- }
- /*
- * Send the chip address again, this time for a read cycle.
- * Then read the data. On the last byte, we do a NACK instead
- * of an ACK(len == 0) to terminate the read.
- */
- write_byte((chip << 1) | 1); /* read cycle */
- while(len-- > 0) {
- *buffer++ = read_byte(len == 0);
- }
- send_stop();
- return(0);
-}
-
-/*-----------------------------------------------------------------------
- * Write bytes
- */
-int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
-{
- int shift, failures = 0;
-
- PRINTD("i2c_write: chip %02X addr %02X alen %d buffer %p len %d\n",
- chip, addr, alen, buffer, len);
-
- send_start();
- if(write_byte(chip << 1)) { /* write cycle */
- send_stop();
- PRINTD("i2c_write, no chip responded %02X\n", chip);
- return(1);
- }
- shift = (alen-1) * 8;
- while(alen-- > 0) {
- if(write_byte(addr >> shift)) {
- PRINTD("i2c_write, address not <ACK>ed\n");
- return(1);
- }
- shift -= 8;
- }
-
- while(len-- > 0) {
- if(write_byte(*buffer++)) {
- failures++;
- }
- }
- send_stop();
- return(failures);
-}
-
-/*-----------------------------------------------------------------------
- * Read a register
- */
-uchar i2c_reg_read(uchar i2c_addr, uchar reg)
-{
- uchar buf;
-
- i2c_read(i2c_addr, reg, 1, &buf, 1);
-
- return(buf);
-}
-
-/*-----------------------------------------------------------------------
- * Write a register
- */
-void i2c_reg_write(uchar i2c_addr, uchar reg, uchar val)
-{
- i2c_write(i2c_addr, reg, 1, &val, 1);
-}