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    SubjectRe: CLK_OF_DECLARE advice required
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    Am 31.05.2017 um 17:27 schrieb Stephen Warren:
    > On 05/30/2017 06:23 AM, Phil Elwell wrote:
    >> Hi,
    >>
    >> I've run into a problem using the fixed-factor clock on Raspberry Pi
    >> and I'd
    >> like some advice before I submit a patch.
    >>
    >> Some context: the aim is to use a standard UART and some external
    >> circuitry
    >> as a MIDI interface. This would be straightforward except that Linux
    >> doesn't
    >> recognise the required 31.25KHz as a valid UART baud rate. Rhe
    >> workaround is
    >> to declare the UART clock such that the reported rate differs from
    >> the actual
    >> rate. If one sets the reported rate to be (actual*38400)/31250 then
    >> requesting a 38400 baud rate will result in an actual 31250 baud signal.
    >
    > This sounds like the wrong approach. Forcing the port to use a
    > different clock rate than the user requests would prevent anyone from
    > using that port for its standard purpose; it'd turn what should be a
    > runtime decision into a compile-time decision.
    >
    > Are you sure there's no way to simply select the correct baud rate on
    > the port? I see plenty of references to configuring custom baud rates
    > under Linux when I search Google, e.g.:
    >
    >> https://stackoverflow.com/questions/12646324/how-to-set-a-custom-baud-rate-on-linux
    >>
    > "How to set a custom baud rate on Linux?"
    >
    >> https://sourceware.org/ml/libc-help/2009-06/msg00016.html
    > "Re: Terminal interface and non-standard baudrates"
    >

    I remember this gist from Peter Hurley:

    https://gist.github.com/peterhurley/fbace59b55d87306a5b8

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