diff options
| -rw-r--r-- | drivers/i2c/omap24xx_i2c.c | 136 |
1 files changed, 58 insertions, 78 deletions
diff --git a/drivers/i2c/omap24xx_i2c.c b/drivers/i2c/omap24xx_i2c.c index 966ffc4..8effc5d 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) |