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    SubjectRe: [PATCH 2/2] i2c-designware-pci: Index Haswell ULT bus names from 0
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    Hi Wolfram,

    On Thu, Nov 14, 2013 at 10:05 AM, Wolfram Sang <wsa@the-dreams.de> wrote:
    >> In the chromeos_laptop driver, I do by-name matching of i2c busses to
    >> find busses and instantiate devices, so there is value to have each
    >> named something predictable.
    >
    > Any why don't you use fixed bus numbers which you can attach the devices
    > to?

    On this particular set of systems, there are two other classes of i2c
    adapters that use dynamically assigned bus numbers, specifically the
    i915 gmbus adapters, and the i801_smbus adapter. This is why
    chromeos_laptop uses the name matching, as some of the boards that it
    supports have devices on those dynamic busses.

    I can't guarantee that these other busses will always have the same
    bus numbers, nor can I guarantee that this driver
    (i2c_designware_pcidrv) is loaded before or after the others, so it
    seemed the right thing to do to to make sure that the names of each of
    the adapters correspond to how they are referred to on various
    schematics and datasheets.


    --
    Benson Leung
    Software Engineer, Chrom* OS
    bleung@chromium.org


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