From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: John Linn <John.Linn@xilinx.com>
Cc: Greg KH <greg@kroah.com>,
linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org
Subject: Re: [PATCH] tty/serial: add support for Xilinx PS UART
Date: Wed, 20 Apr 2011 10:39:28 +0100 [thread overview]
Message-ID: <20110420103928.4049573f@lxorguk.ukuu.org.uk> (raw)
In-Reply-To: <68925dd6-03b8-48af-9f96-0a3f611712e1@VA3EHSMHS020.ehs.local>
> Reading up on it a bit as I'm not an expert on it (like you).
> It's not clear to me what the device driver uses for it's major/minor in
> this case.
If you don't specify then the kernel picks one. udev can then create the
right /dev/ttyPS1/2/3 nodes itself. If you have devtmpfs enabled then
devtmpfs is a virtual file system which will just have the nodes in at as
specified by the drivers. It eliminates all the hard work maintaining
device nodes/ranges in user space.
> The only reason we didn't just use ttyS0 was that it's not a 8250 really
If you'd attempted to use ttyS0 you would indeed have been told to change
it
> and
> since we have are an FPGA people can add real 8250s in soft logic and
> then
> the system would get confusing.
and that's exactly why !
Alan
next prev parent reply other threads:[~2011-04-20 9:38 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-04-19 20:14 [PATCH] tty/serial: add support for Xilinx PS UART John Linn
2011-04-19 21:15 ` Alan Cox
2011-04-19 21:51 ` John Linn
2011-04-20 9:25 ` Alan Cox
2011-04-20 13:43 ` John Linn
2011-04-19 22:22 ` John Linn
2011-04-19 23:21 ` Greg KH
2011-04-19 23:39 ` John Linn
2011-04-19 23:42 ` Greg KH
2011-04-19 23:47 ` John Linn
2011-04-20 9:39 ` Alan Cox [this message]
2011-04-20 15:19 ` John Linn
2011-04-20 15:35 ` Alan Cox
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