* Tony Lindgren <[EMAIL PROTECTED]> [080328 13:47]:
> For some reason doing a twl4030 write-read cycle can hang the I2C bus
> on omap3430. And doing the write and read separately in twl4030_i2c_read()
> seems to fix the problem...
> 
> Not intended for applying, just a temporary workaround.

Uh, please ignore this one, git-send-email weirdness where it sends
all files ending in .patch.. The series should only contain two patches.

Tony

> 
> diff --git a/drivers/i2c/chips/twl4030-core.c 
> b/drivers/i2c/chips/twl4030-core.c
> index ded86e7..62868b0 100644
> --- a/drivers/i2c/chips/twl4030-core.c
> +++ b/drivers/i2c/chips/twl4030-core.c
> @@ -327,6 +327,7 @@ int twl4030_i2c_read(u8 mod_no, u8 * value, u8 reg, u8 
> num_bytes)
>               return -EPERM;
>       }
>       mutex_lock(&twl->xfer_lock);
> +
>       /* [MSG1] fill the register address data */
>       msg = &twl->xfer_msg[0];
>       msg->addr = twl->address;
> @@ -334,18 +335,25 @@ int twl4030_i2c_read(u8 mod_no, u8 * value, u8 reg, u8 
> num_bytes)
>       msg->flags = 0; /* Read the register value */
>       val = twl4030_map[mod_no].base + reg;
>       msg->buf = &val;
> +     ret = i2c_transfer(twl->client.adapter, twl->xfer_msg, 1);
> +     if (ret < 0)
> +             goto out;
> + 
>       /* [MSG2] fill the data rx buffer */
>       msg = &twl->xfer_msg[1];
>       msg->addr = twl->address;
>       msg->flags = I2C_M_RD;  /* Read the register value */
>       msg->len = num_bytes;   /* only n bytes */
>       msg->buf = value;
> -     ret = i2c_transfer(twl->client.adapter, twl->xfer_msg, 2);
> +     ret = i2c_transfer(twl->client.adapter, twl->xfer_msg, 1);
> +
> +out:
>       mutex_unlock(&twl->xfer_lock);
>  
>       /* i2cTransfer returns num messages.translate it pls.. */
>       if (ret >= 0)
>               ret = 0;
> +
>       return ret;
>  }
>  
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