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    SubjectRe: [PATCH V2] i2c-imx: do not allow interruptions when waiting for I2C to complete (resend)
    Ben Dooks wrote:
    > On Tue, Jun 15, 2010 at 12:20:38PM +0200, Marc Kleine-Budde wrote:
    >> The i2c_imx_trx_complete() function is using
    >> wait_event_interruptible_timeout() to wait for the I2C controller to
    >> signal that it has completed an I2C bus operation. If the process that
    >> causes the I2C operation receives a signal, the wait will be
    >> interrupted, returning an error. It is better to let the I2C operation
    >> finished before handling the signal (i.e. returning into userspace).
    >> It is safe to use wait_event_timeout() instead, because the timeout
    >> will allow the process to exit if the I2C bus hangs. It's also better
    >> to allow the I2C operation to finish, because unacknowledged I2C
    >> operations can cause the I2C bus to hang.
    > Hmm, if it times out, do you need to at-least try sending a stop
    > on the bus? or does the caller do that for you?

    The caller of the caller does this. "i2c_imx_xfer" will call
    "i2c_imx_stop", and this function will generate the stop condition if
    not already done so.

    I'm sending a V3 version of the patch, which removes the only written to
    variable "result".

    cheers, Marc

    Pengutronix e.K. | Marc Kleine-Budde |
    Industrial Linux Solutions | Phone: +49-231-2826-924 |
    Vertretung West/Dortmund | Fax: +49-5121-206917-5555 |
    Amtsgericht Hildesheim, HRA 2686 | |

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