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From: "Tobias Arp" <tobiasarp@gmx.de>
To: linux-serial@vger.kernel.org
Subject: ST16C654 stoppes transmitting after a while
Date: Tue, 17 Jul 2012 09:43:55 +0200	[thread overview]
Message-ID: <20120717074355.80180@gmx.net> (raw)

Hi,

we use on our system (ARM board Processor EP9315) a quad uart (ST16C654) with kernel 3.2 (the quad uart is connected only to one irq, so the four interfaces of the quad uart have to share this irq). Multiple simultanous  connections are working fine for some hours (3 Modem connections and one null modem connection / transferring data in both directions with hardware handshake (CRTSCTS) enabled). Then one connection can't send data to the remote host anymore (often the null modem connection). The driver is the 8250 serial driver.

I found out that the hw_stopped flag is set to 1 but not set to 0 again although CTS is set (measuring with the oscilloscope and reading out the modem status register are confirming this / i modified the serial8250_get_mctrl function to print out these values).

It seems to me that an CTS change (UART_MSR_DCTS) is lost.
Could this cause this behaviour?

Any suggestions for a workaround are appreciated.

Thanks in  advance

Tobias





             reply	other threads:[~2012-07-17  7:43 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-07-17  7:43 Tobias Arp [this message]
2012-07-17  9:52 ` ST16C654 stoppes transmitting after a while Alan Cox
2012-07-17 10:05   ` Tobias Arp
2012-07-17 11:21     ` Alan Cox
2012-07-17 11:36       ` Tobias Arp
2012-07-17 16:38         ` Alan Cox
2012-07-18  6:37           ` Tobias Arp
2012-07-18  7:45             ` Tobias Arp
2012-07-18 11:08               ` Alan Cox
2012-07-18 11:16                 ` Tobias Arp
2012-07-20  4:25             ` Tobias Arp
2012-07-20 10:10             ` Tobias Arp

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