From: Joerg Roedel <jroedel@xxxxxxx> 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: Peter Hurley <peter@xxxxxxxxxxxxxxxxxx> Cc: Michael Welling <mwelling@xxxxxxxx> Cc: Joe Schultz <jschultz@xxxxxxxxxxx> Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> --- drivers/tty/serial/8250/8250_core.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index 37fff12..4124a91 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -2164,6 +2164,21 @@ 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()) -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html