Commit da891641 authored Jul 16, 2015 by Joerg Roedel Committed by Greg Kroah-Hartman Jul 23, 2015

serial: 8250: Do XR17V35X specific wakeup in serial8250_do_startup



The XR17V35X UART needs the ECB bit set in its XR_EFR
register to enable access to IER [7:5], ISR [5:4], FCR[5:4],
MCR[7:5], and MSR [7:0].

Also reset the IER register to mask interrupts after access
to all bits of this register has been enabled.

This makes my 8-port XR17V35X working with the in-kernel
serial driver.

Cc: Joe Schultz <jschultz@xes-inc.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent ee3ad90b

drivers/tty/serial/8250/8250_port.c

+15 −0

Original line number	Diff line number	Diff line
		@@ -1834,6 +1834,21 @@ int serial8250_do_startup(struct uart_port *port)
		*/
		enable_rsa(up);
		#endif

		if (port->type == PORT_XR17V35X) {
		/*
		* First enable access to IER [7:5], ISR [5:4], FCR [5:4],
		* MCR [7:5] and MSR [7:0]
		*/
		serial_port_out(port, UART_XR_EFR, UART_EFR_ECB);

		/*
		* Make sure all interrups are masked until initialization is
		* complete and the FIFOs are cleared
		*/
		serial_port_out(port, UART_IER, 0);
		}

		/*
		* Clear the FIFO buffers and disable them.
		* (they will be reenabled in set_termios())