Re: [PATCH V2] i2c: designware: fix race between subsequent xfers

From: Andy Shevchenko
Date: Fri Jun 07 2013 - 05:19:14 EST


On Fri, Jun 7, 2013 at 11:51 AM, Christian Ruppert
<christian.ruppert@xxxxxxxxxx> wrote:
> The designware block is not always properly disabled in the case of
> transfer errors. Interrupts from aborted transfers might be handled
> after the data structures for the following transfer are initialised but
> before the hardware is set up. This can corrupt the data structures to
> the point that the system is stuck in an infinite interrupt loop (where
> FIFOs are never emptied because dev->msg_read_idx == dev->msgs_num).
>
> This patch cleanly disables the designware-i2c hardware at the end of
> every transfer, be it successful or not.
>
> This patch requires https://patchwork.kernel.org/patch/2601241/ to be
> applied first.

What if you just move disabling code from i2c_dw_xfer_init() to the
top of i2c_dw_xfer() ?
Will it help?

--
With Best Regards,
Andy Shevchenko
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/