From: txcotrader <txcotrader@gmail.com>
Date: Thu, 4 Apr 2013 17:04:59 -0700 (PDT)
Subject: [U-Boot] PPC4XX Custom Board - Failing to read I2C
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Message-ID: <1365120299377-151609.post@n7.nabble.com>
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To: u-boot@lists.denx.de

After looking deeper I've found a difference in register values when
performing drivers/i2c/ppc4xx_i2c.c->i2c_transfer function.

v1.7.02 code yields:

/* Transfer is in progress
         * we have to wait for upto 5 bytes of data
         * 1 byte chip address+r/w bit then bc bytes
         * of data.
         * udelay(10) is 1 bit time at 100khz
         * Doubled for slop. 20 is too small.
         */
        i = 2*5*8;
        do {
            /* Get status */
            status = in_8((u8 *)IIC_STS);
            printf("gd_ do status->i = %d, status = %d\n", i, status);
            udelay(20);
            i--;
        } while ((status & IIC_STS_PT) && !(status & IIC_STS_ERR) && (i >
0));

gd_ do status->i = 80, status = 40


v2013.01.01 Yields:
        i = 2 * 5 * 8;
        do {
            /* Get status */
            status = in_8(&i2c->sts);
            printf("gd_ do status->i = %d, status = %d\n", i, status);
            udelay(10);
            i--;
        } while ((status & IIC_STS_PT) && !(status & IIC_STS_ERR) &&
             (i > 0));

gd_ do status->i = 80, status = 40

v1.7.02 - include/4xx_i2c.h:#define IIC_STS	
(I2C_REGISTERS_BASE_ADDRESS+IICSTS)
v2013.01.01 - struct ppc4xx_i2c *i2c = (struct ppc4xx_i2c *)I2C_BASE_ADDR;

Newb question, but I should be able to add an offset to correct this issue
right?

Thanks






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