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    SubjectRe: [PATCH 10/13] tty: serial: omap: remove some dead code
    Hi,

    On Thu, Apr 24, 2014 at 11:41:15AM +1000, NeilBrown wrote:
    > On Wed, 23 Apr 2014 20:21:00 -0500 Felipe Balbi <balbi@ti.com> wrote:
    >
    > > I have no problem either way, just that unused code doesn't have to be
    > > sitting in the tree and I'm not entirely sure this GPIO should be
    > > handled by omap-serial.c, perhaps something more generic inside
    > > serial-core so other UART drivers can benefit from it.
    >
    > Perhaps. But there there are more people I need to convince :-)

    heh, Greg is in Cc, that'd be a good start.

    > > > On the other hand, if you can point out to me what I'm missing, and how I can
    > > > solve my problem with any virtual GPIOs, I'm all ears.
    > > >
    > > > To make my problem simple and explicit: I have a device attached to a UART
    > > > which has a separate regulator. The regulator should be powered on if and
    > >
    > > So you're using DTR to power the GPIO and hoping that the regulator
    > > stabilizes quickly enough so that by the time your open() finishes you
    > > don't have to add nonsensical msleep() calls before writing to the
    > > device. Sounds a bit fragile to me.
    >
    > The gpio_set call is synchronous, and the gpio-regulator driver could add a

    sure, but it's synchronous towards toggling the GPIO, pulling it high.
    It doesn't guarantee that the far-end regulator's output will be fully
    changed.

    > delay (I think).

    yeah, that'd be part of the regulator-gpio with the startup-delay-ns
    property (IIRC)

    > > > only if the /dev/ttyXX interface to the UART is open. The device is a
    > > > bluetooth transceiver.
    > >
    > > considering this is a BTUART device, why didn't you do this at the ldisc
    > > level ? hci_uart_open() sounds like a good choice from a quick thinking.
    > >
    >
    > I'll have a look into that, thanks.

    so, Ack for $subject or not ?

    --
    balbi
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