leandrof/u-boot
1
0
Fork 1
Code Issues Pull Requests Packages Projects Releases Wiki Activity

ARMV7: OMAP: Write more than 1 byte at a time in i2c_write

Browse Source 
This allows the EEPROM layer to send a single i2c write command
per page, and wait CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS between
i2c write commands.

Signed-off-by: Michael Jones <michael.jones@matrix-vision.de>
Acked-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>
This commit is contained in:
Michael Jones 2011-09-04 14:01:55 -04:00 committed by Albert ARIBAUD
parent 569919d8e2
commit 0607e2b97a
1 changed files with 58 additions and 78 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

136
drivers/i2c/omap24xx_i2c.c
View File

@ -216,77 +216,6 @@ read_exit:
return i2c_error;
}
static int i2c_write_byte (u8 devaddr, u8 regoffset, u8 value)
{
int i2c_error = 0;
u16 status;
/* wait until bus not busy */
wait_for_bb ();
/* two bytes */
writew (2, &i2c_base->cnt);
/* set slave address */
writew (devaddr, &i2c_base->sa);
/* stop bit needed here */
writew (I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
I2C_CON_STP, &i2c_base->con);
while (1) {
status = wait_for_pin();
if (status == 0 || status & I2C_STAT_NACK) {
i2c_error = 1;
goto write_exit;
}
if (status & I2C_STAT_XRDY) {
#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
defined(CONFIG_OMAP44XX)
/* send register offset */
writeb(regoffset, &i2c_base->data);
writew(I2C_STAT_XRDY, &i2c_base->stat);
while (1) {
status = wait_for_pin();
if (status == 0 || status & I2C_STAT_NACK) {
i2c_error = 1;
goto write_exit;
}
if (status & I2C_STAT_XRDY) {
/* send data */
writeb(value, &i2c_base->data);
writew(I2C_STAT_XRDY, &i2c_base->stat);
}
if (status & I2C_STAT_ARDY) {
writew(I2C_STAT_ARDY, &i2c_base->stat);
break;
}
}
break;
#else
/* send out two bytes */
writew((value << 8) + regoffset, &i2c_base->data);
writew(I2C_STAT_XRDY, &i2c_base->stat);
#endif
}
if (status & I2C_STAT_ARDY) {
writew(I2C_STAT_ARDY, &i2c_base->stat);
break;
}
}
wait_for_bb();
status = readw(&i2c_base->stat);
if (status & I2C_STAT_NACK)
i2c_error = 1;
write_exit:
flush_fifo();
writew (0xFFFF, &i2c_base->stat);
writew (0, &i2c_base->cnt);
return i2c_error;
}
static void flush_fifo(void)
{ u16 stat;
@ -372,26 +301,77 @@ int i2c_read (uchar chip, uint addr, int alen, uchar * buffer, int len)
int i2c_write (uchar chip, uint addr, int alen, uchar * buffer, int len)
{
int i;
u16 status;
int i2c_error = 0;
if (alen > 1) {
printf ("I2C read: addr len %d not supported\n", alen);
printf("I2C write: addr len %d not supported\n", alen);
return 1;
}
if (addr + len > 256) {
printf ("I2C read: address out of range\n");
printf("I2C write: address 0x%x + 0x%x out of range\n",
addr, len);
return 1;
}
/* wait until bus not busy */
wait_for_bb();
/* start address phase - will write regoffset + len bytes data */
/* TODO consider case when !CONFIG_OMAP243X/34XX/44XX */
writew(alen + len, &i2c_base->cnt);
/* set slave address */
writew(chip, &i2c_base->sa);
/* stop bit needed here */
writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
I2C_CON_STP, &i2c_base->con);
/* Send address byte */
status = wait_for_pin();
if (status == 0 || status & I2C_STAT_NACK) {
i2c_error = 1;
printf("error waiting for i2c address ACK (status=0x%x)\n",
status);
goto write_exit;
}
if (status & I2C_STAT_XRDY) {
writeb(addr & 0xFF, &i2c_base->data);
writew(I2C_STAT_XRDY, &i2c_base->stat);
} else {
i2c_error = 1;
printf("i2c bus not ready for transmit (status=0x%x)\n",
status);
goto write_exit;
}
/* address phase is over, now write data */
for (i = 0; i < len; i++) {
if (i2c_write_byte (chip, addr + i, buffer[i])) {
printf ("I2C read: I/O error\n");
i2c_init (CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
return 1;
status = wait_for_pin();
if (status == 0 || status & I2C_STAT_NACK) {
i2c_error = 1;
printf("i2c error waiting for data ACK (status=0x%x)\n",
status);
goto write_exit;
}
if (status & I2C_STAT_XRDY) {
writeb(buffer[i], &i2c_base->data);
writew(I2C_STAT_XRDY, &i2c_base->stat);
} else {
i2c_error = 1;
printf("i2c bus not ready for Tx (i=%d)\n", i);
goto write_exit;
}
}
return 0;
write_exit:
flush_fifo();
writew(0xFFFF, &i2c_base->stat);
return i2c_error;
}
static void wait_for_bb (void)