From: David Brownell <david-b@pacbell.net>
To: Michael Buesch <mb@bu3sch.de>
Cc: Andrew Morton <akpm@linux-foundation.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] spi-gpio: Implement spidelay() for busses that need it.
Date: Mon, 16 Feb 2009 12:42:27 -0800 [thread overview]
Message-ID: <200902161242.27773.david-b@pacbell.net> (raw)
In-Reply-To: <200902151923.00120.mb@bu3sch.de>
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On Sunday 15 February 2009, Michael Buesch wrote:
> + * NOTE: to clock "as fast as we can", set spi_device.max_speed_hz
> + * and spi_transfer.speed_hz to 0.
Won't work; if spi->max_speed_hz is zero, spi_async() and
friends will refuse to queue any messages.
I'm not averse to a solution that lets some boards use a
slowed-down bitbang loop. But it would be a lot easier
if you kept the default the way it is, and just added
that slowdown as an option for the existing customization
case (currently oriented towards speedup, not slowdown).
- Dave
next prev parent reply other threads:[~2009-02-16 20:42 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-02-15 18:22 [PATCH] spi-gpio: Implement spidelay() for busses that need it Michael Buesch
2009-02-16 20:42 ` David Brownell [this message]
2009-02-16 21:53 ` Michael Buesch
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