From mboxrd@z Thu Jan  1 00:00:00 1970
From: Michael Hanselmann <linux-kernel@hansmi.ch>
Subject: Re: Hang in uart_block_til_ready()
Date: Sun, 2 Apr 2006 17:42:40 +0200
Message-ID: <20060402154240.GB402@hansmi.ch>
References: <20060402135138.GC2954@hansmi.ch> <20060402143827.GA3565@flint.arm.linux.org.uk> <20060402151739.GA402@hansmi.ch> <20060402152350.GA5283@flint.arm.linux.org.uk>
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On Sun, Apr 02, 2006 at 04:23:50PM +0100, Russell King wrote:
> Have you checked the state of the DCD line in both cases?  Look in
> /proc/tty/driver/serial.

HP box:
2: uart:16550A port:000003E8 irq:4 tx:12888 rx:147 RTS|CTS|DTR|DSR

other box:
0: uart:16550A port:000003F8 irq:4 tx:18886 rx:299 RTS|CTS|DTR|DSR|CD

So, yes. The other box has CD set (unless CD is not DCD). It might be
that the serial cable used there does this, but I can't check it because
the box is several hundreds of kilometers away.

> Probably "works" on the first box because it happens to have DCD asserted
> on the real serial port.

Yes, that explains it.

Thanks for your help,
Michael

--=20
Gentoo Linux developer, http://hansmi.ch/, http://forkbomb.ch/

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