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Merge branch 'master' of git://git.denx.de/u-boot-i2c

utp
Wolfgang Denk 2009-09-07 23:20:04 +02:00
commit 0052a051f6
4 changed files with 77 additions and 4 deletions

7
README
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@ -1366,6 +1366,13 @@ The following options need to be configured:
therefore be cleared to 0 (See, eg, MPC823e User's Manual
p.16-473). So, set CONFIG_SYS_I2C_SLAVE to 0.
CONFIG_SYS_I2C_INIT_MPC5XXX
When a board is reset during an i2c bus transfer
chips might think that the current transfer is still
in progress. Reset the slave devices by sending start
commands until the slave device responds.
That's all that's required for CONFIG_HARD_I2C.
If you use the software i2c interface (CONFIG_SOFT_I2C)

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@ -207,6 +207,52 @@ static int receive_bytes(uchar chip, char *buf, int len)
return 0;
}
#if defined(CONFIG_SYS_I2C_INIT_MPC5XXX)
#define FDR510(x) (u8) (((x & 0x20) >> 3) | (x & 0x3))
#define FDR432(x) (u8) ((x & 0x1C) >> 2)
/*
* Reset any i2c devices that may have been interrupted during a system reset.
* Normally this would be accomplished by clocking the line until SCL and SDA
* are released and then sending a start condtiion (From an Atmel datasheet).
* There is no direct access to the i2c pins so instead create start commands
* through the i2c interface. Send a start command then delay for the SDA Hold
* time, repeat this by disabling/enabling the bus a total of 9 times.
*/
static void send_reset(void)
{
struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE;
int i;
u32 delay;
u8 fdr;
int SDA_Tap[] = { 3, 3, 4, 4, 1, 1, 2, 2};
struct mpc5xxx_i2c_tap scltap[] = {
{4, 1},
{4, 2},
{6, 4},
{6, 8},
{14, 16},
{30, 32},
{62, 64},
{126, 128}
};
fdr = (u8)mpc_reg_in(&regs->mfdr);
delay = scltap[FDR432(fdr)].scl2tap + ((SDA_Tap[FDR510(fdr)] - 1) * \
scltap[FDR432(fdr)].tap2tap) + 3;
for (i = 0; i < 9; i++) {
mpc_reg_out(&regs->mcr, I2C_EN|I2C_STA|I2C_TX, I2C_INIT_MASK);
udelay(delay);
mpc_reg_out(&regs->mcr, 0, I2C_INIT_MASK);
udelay(delay);
}
mpc_reg_out(&regs->mcr, I2C_EN, I2C_INIT_MASK);
}
#endif /* CONFIG_SYS_I2c_INIT_MPC5XXX */
/**************** I2C API ****************/
void i2c_init(int speed, int saddr)
@ -225,6 +271,9 @@ void i2c_init(int speed, int saddr)
mpc_reg_out(&regs->mcr, I2C_EN, I2C_INIT_MASK);
mpc_reg_out(&regs->msr, 0, I2C_IF);
#if defined(CONFIG_SYS_I2C_INIT_MPC5XXX)
send_reset();
#endif
return;
}

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@ -1,5 +1,5 @@
/*
* Copyright 2006 Freescale Semiconductor, Inc.
* Copyright 2006,2009 Freescale Semiconductor, Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
@ -26,7 +26,21 @@
#include <asm/io.h>
#include <asm/fsl_i2c.h> /* HW definitions */
#define I2C_TIMEOUT (CONFIG_SYS_HZ / 4)
/* The maximum number of microseconds we will wait until another master has
* released the bus. If not defined in the board header file, then use a
* generic value.
*/
#ifndef CONFIG_I2C_MBB_TIMEOUT
#define CONFIG_I2C_MBB_TIMEOUT 100000
#endif
/* The maximum number of microseconds we will wait for a read or write
* operation to complete. If not defined in the board header file, then use a
* generic value.
*/
#ifndef CONFIG_I2C_TIMEOUT
#define CONFIG_I2C_TIMEOUT 10000
#endif
#define I2C_READ_BIT 1
#define I2C_WRITE_BIT 0
@ -213,9 +227,10 @@ static __inline__ int
i2c_wait4bus(void)
{
unsigned long long timeval = get_ticks();
const unsigned long long timeout = usec2ticks(CONFIG_I2C_MBB_TIMEOUT);
while (readb(&i2c_dev[i2c_bus_num]->sr) & I2C_SR_MBB) {
if ((get_ticks() - timeval) > usec2ticks(I2C_TIMEOUT))
if ((get_ticks() - timeval) > timeout)
return -1;
}
@ -227,6 +242,7 @@ i2c_wait(int write)
{
u32 csr;
unsigned long long timeval = get_ticks();
const unsigned long long timeout = usec2ticks(CONFIG_I2C_TIMEOUT);
do {
csr = readb(&i2c_dev[i2c_bus_num]->sr);
@ -251,7 +267,7 @@ i2c_wait(int write)
}
return 0;
} while ((get_ticks() - timeval) < usec2ticks(I2C_TIMEOUT));
} while ((get_ticks() - timeval) < timeout);
debug("i2c_wait: timed out\n");
return -1;

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@ -110,6 +110,7 @@
#define CONFIG_SYS_I2C_MODULE 2 /* Select I2C module #1 or #2 */
#define CONFIG_SYS_I2C_SPEED 100000 /* 100 kHz */
#define CONFIG_SYS_I2C_SLAVE 0x7F
#define CONFIG_SYS_I2C_INIT_MPC5XXX /* Reset devices on i2c bus */
/*
* EEPROM CAT24WC32 configuration