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    Subject[PATCH 17/30] W1: w1_io.c reset comments and msleep
    w1_reset_bus, added some comments about the timing and switched to
    msleep for the later delay. I don't have the hardware to test the
    sleep after reset change. The one wire doesn't have a timing requirement between commands so it is fine. I do have the USB hardware and it would be in big trouble with 10ms interrupt transfers
    to find that the reset completed.

    Signed-off-by: David Fries <david@fries.net>
    Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
    ---
    drivers/w1/w1_io.c | 14 +++++++++++++-
    1 files changed, 13 insertions(+), 1 deletions(-)

    diff --git a/drivers/w1/w1_io.c b/drivers/w1/w1_io.c
    index a2f0d5f..dd2ecef 100644
    --- a/drivers/w1/w1_io.c
    +++ b/drivers/w1/w1_io.c
    @@ -293,12 +293,24 @@ int w1_reset_bus(struct w1_master *dev)
    result = dev->bus_master->reset_bus(dev->bus_master->data) & 0x1;
    else {
    dev->bus_master->write_bit(dev->bus_master->data, 0);
    + /* minimum 480, max ? us
    + * be nice and sleep, except 18b20 spec lists 960us maximum,
    + * so until we can sleep with microsecond accuracy, spin.
    + * Feel free to come up with some other way to give up the
    + * cpu for such a short amount of time AND get it back in
    + * the maximum amount of time.
    + */
    w1_delay(480);
    dev->bus_master->write_bit(dev->bus_master->data, 1);
    w1_delay(70);

    result = dev->bus_master->read_bit(dev->bus_master->data) & 0x1;
    - w1_delay(410);
    + /* minmum 70 (above) + 410 = 480 us
    + * There aren't any timing requirements between a reset and
    + * the following transactions. Sleeping is safe here.
    + */
    + /* w1_delay(410); min required time */
    + msleep(1);
    }

    return result;
    --
    1.4.4.4[unhandled content-type:application/pgp-signature]
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