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SubjectRe: [PATCH v7 3/3] gpio: pca953x: fix address calculation for pcal6524
On Thu, May 17, 2018 at 6:59 AM, H. Nikolaus Schaller <> wrote:

> The register constants are so far defined in a way that they fit
> for the pcal9555a when shifted by the number of banks, i.e. are
> multiplied by 2 in the accessor function.
> Now, the pcal6524 has 3 banks which means the relative offset
> is multiplied by 4 for the standard registers.
> Simply applying the bit shift to the extended registers gives
> a wrong result, since the base offset is already included in
> the offset.
> Therefore, we have to add code to the 24 bit accessor functions
> that adjusts the register number for these exended registers.
> The formula finally used was developed and proposed by
> Andy Shevchenko <>.
> Suggested-by: Andy Shevchenko <>
> Signed-off-by: H. Nikolaus Schaller <>

Patch applied.

Linus Walleij

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