• Evgeniy Polyakov's avatar
    [PATCH] w1: Added default generic read/write operations. · f522d239
    Evgeniy Polyakov authored
    Special file in each w1 slave device's directory called "rw" is created
    each time new slave and no appropriate w1 family is registered.
    "rw" file supports read and write operations, which allows to perform
    almost any kind of operations. Each logical operation is a transaction
    in nature, which can contain several (two or one) low-level operations.
    Let's see how one can read EEPROM context:
    1. one must write control buffer, i.e. buffer containing command byte
    and two byte address. At this step bus is reset and appropriate device
    is selected using either W1_SKIP_ROM or W1_MATCH_ROM command.
    Then provided control buffer is being written to the wire.
    2. reading. This will issue reading eeprom response.
    It is possible that between 1. and 2. w1 master thread will reset bus for
    searching and slave device will be even removed, but in this case 0xff will
    be read, since no device was selected.
    Signed-off-by: default avatarEvgeniy Polyakov <johnpol@2ka.mipt.ru>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
w1.generic 4.41 KB