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    SubjectRe: [PATCH 2/2] gpiolib: Fix array members of same chip processed separately
    On Mon, Sep 24, 2018 at 1:52 AM Janusz Krzysztofik <jmkrzyszt@gmail.com> wrote:

    > New code introduced by commit bf9346f5d47b ("gpiolib: Identify arrays
    > matching GPIO hardware") forcibly tries to find an array member which
    > has its array index number equal to its hardware pin number and set
    > up an array info for possible fast bitmap processing of all arrray
    > pins belonging to that chip which also satisfy that numbering rule.
    >
    > Depending on array content, it may happen that consecutive array
    > members which belong to the same chip but don't have array indexes
    > equal to their pin hardware numbers will be split into groups, some of
    > them processed together via the fast bitmap path, and rest of them
    > separetely. However, applications may expect all those pins being
    > processed together with a single call to .set_multiple() chip callback,
    > like that was done before the change.
    >
    > Limit applicability of fast bitmap processing path to cases where all
    > pins of consecutive array members starting from 0 which belong to the
    > same chip have their hardware numbers equal to their corresponding
    > array indexes. That should still speed up processing of applications
    > using whole GPIO banks as I/O ports, while not breaking simultaneous
    > manipulation of consecutive pins of the same chip which don't follow
    > the equal numbering rule.
    >
    > Cc: Jonathan Corbet <corbet@lwn.net>
    > Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>

    Patch applied!

    Yours,
    Linus Walleij

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