Re: [PATCH v5] gpio: add support for FTDI's MPSSE as GPIO

From: Greg KH
Date: Sun Oct 13 2024 - 10:52:41 EST


On Wed, Oct 09, 2024 at 09:11:31AM -0400, Mary Strodl wrote:
> FTDI FT2232H is a USB to GPIO chip. Sealevel produces some devices
> with this chip. FT2232H presents itself as a composite device with two
> interfaces (each is an "MPSSE"). Each MPSSE has two banks (high and low)
> of 8 GPIO each. I believe some MPSSE's have only one bank, but I don't
> know how to identify them (I don't have any for testing) and as a result
> are unsupported for the time being.
>
> Additionally, this driver provides software polling-based interrupts for
> edge detection. For the Sealevel device I have to test with, this works
> well because there is hardware debouncing. From talking to Sealevel's
> people, this is their preferred way to do edge detection.
>
> Signed-off-by: Mary Strodl <mstrodl@xxxxxxxxxxx>
> Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
> ---
>
> (Resent because I forgot to cc gregkh last time)

USB stuff looks sane, no objection from me there.