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>

diff --git a/drivers/i2c/omap24xx_i2c.c b/drivers/i2c/omap24xx_i2c.c
index 966ffc4bfff768859dc5afb9ddfbf4363ca4a218..8effc5d520eb3026e0802229fa1c90e01dca2efe 100644 (file)
--- 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)