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authorMichael Jones <[michael.jones@matrix-vision.de]>2011-09-04 14:01:55 -0400
committerAlbert ARIBAUD <albert.u.boot@aribaud.net>2011-09-12 17:40:48 +0200
commit0607e2b97a907ed3bdf926227e5ad0603a6216ad (patch)
tree860b1b838d48d23cf85f532403d0b4b553ccc8a2
parent569919d8e284c36d4ee981df5fcaa2e188f006a0 (diff)
downloadu-boot-linaro-stable-0607e2b97a907ed3bdf926227e5ad0603a6216ad.tar.gz
ARMV7: OMAP: Write more than 1 byte at a time in i2c_write
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>
-rw-r--r--drivers/i2c/omap24xx_i2c.c136
1 files changed, 58 insertions, 78 deletions
diff --git a/drivers/i2c/omap24xx_i2c.c b/drivers/i2c/omap24xx_i2c.c
index 966ffc4bf..8effc5d52 100644
--- a/drivers/i2c/omap24xx_i2c.c
+++ b/drivers/i2c/omap24xx_i2c.c
@@ -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)