3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jonas Gorski <jonas.gor...@gmail.com>

commit 0a5191efe06b5103909206e4fbcff81d30283f8e upstream.

Since commit aef9a7bd9b67 ("serial/uart/8250: Add tunable RX interrupt
trigger I/F of FIFO buffers"), the port's default FCR value isn't used
in serial8250_do_set_termios anymore, but copied over once in
serial8250_config_port and then modified as needed.

Unfortunately, serial8250_config_port will never be called if the port
is shared between kernel and userspace, and the port's flag doesn't have
UPF_BOOT_AUTOCONF, which would trigger a serial8250_config_port as well.

This causes garbled output from userspace:

[    5.220000] random: procd urandom read with 49 bits of entropy available
ers
   [kee

Fix this by forcing it to be configured on boot, resulting in the
expected output:

[    5.250000] random: procd urandom read with 50 bits of entropy available
Press the [f] key and hit [enter] to enter failsafe mode
Press the [1], [2], [3] or [4] key and hit [enter] to select the debug level

Fixes: aef9a7bd9b67 ("serial/uart/8250: Add tunable RX interrupt trigger I/F of 
FIFO buffers")
Signed-off-by: Jonas Gorski <jonas.gor...@gmail.com>
Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Cc: Yoshihiro YUNOMAE <yoshihiro.yunomae...@hitachi.com>
Cc: Florian Fainelli <f.faine...@gmail.com>
Cc: Nicolas Schichan <nschic...@freebox.fr>
Cc: linux-m...@linux-mips.org
Cc: linux-ser...@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17544/
Signed-off-by: Ralf Baechle <r...@linux-mips.org>
Cc: James Hogan <jho...@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 arch/mips/ar7/platform.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/mips/ar7/platform.c
+++ b/arch/mips/ar7/platform.c
@@ -581,7 +581,7 @@ static int __init ar7_register_uarts(voi
        uart_port.type          = PORT_AR7;
        uart_port.uartclk       = clk_get_rate(bus_clk) / 2;
        uart_port.iotype        = UPIO_MEM32;
-       uart_port.flags         = UPF_FIXED_TYPE;
+       uart_port.flags         = UPF_FIXED_TYPE | UPF_BOOT_AUTOCONF;
        uart_port.regshift      = 2;
 
        uart_port.line          = 0;


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