tty: serial: exar: Relocate sleep wake-up handling

Exar sleep wake-up handling has been done on a per-channel basis by
virtue of INT0 being accessible from each channel's address space. I
believe this was initially done out of necessity, but now that Exar
devices have their own driver, we can do things more efficiently by
registering a dedicated INT0 handler at the PCI device level.

I see this change providing the following benefits:

    1. If more than one port is active, eliminates the redundant bus
       cycles for reading INT0 on every interrupt.
    2. This note associated with hooking in the per-channel handler in
       8250_port.c is resolved:
        /* Fixme: probably not the best place for this */

Cc: Matt Schulte <matts@commtech-fastcom.com>
Signed-off-by: Aaron Sierra <asierra@xes-inc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 0 insertions, 26 deletions

diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 11434551ac0a..1328c7e70108 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -441,7 +441,6 @@ static void io_serial_out(struct uart_port *p, int offset, int value)
 }
 
 static int serial8250_default_handle_irq(struct uart_port *port);
-static int exar_handle_irq(struct uart_port *port);
 
 static void set_io_from_upio(struct uart_port *p)
 {
@@ -1884,26 +1883,6 @@ static int serial8250_default_handle_irq(struct uart_port *port)
 }
 
 /*
- * These Exar UARTs have an extra interrupt indicator that could
- * fire for a few unimplemented interrupts.  One of which is a
- * wakeup event when coming out of sleep.  Put this here just
- * to be on the safe side that these interrupts don't go unhandled.
- */
-static int exar_handle_irq(struct uart_port *port)
-{
-	unsigned int iir = serial_port_in(port, UART_IIR);
-	int ret = 0;
-
-	if (((port->type == PORT_XR17V35X) || (port->type == PORT_XR17D15X)) &&
-	    serial_port_in(port, UART_EXAR_INT0) != 0)
-		ret = 1;
-
-	ret |= serial8250_handle_irq(port, iir);
-
-	return ret;
-}
-
-/*
  * Newer 16550 compatible parts such as the SC16C650 & Altera 16550 Soft IP
  * have a programmable TX threshold that triggers the THRE interrupt in
  * the IIR register. In this case, the THRE interrupt indicates the FIFO
@@ -3067,11 +3046,6 @@ static void serial8250_config_port(struct uart_port *port, int flags)
 	if (port->type == PORT_UNKNOWN)
 		serial8250_release_std_resource(up);
 
-	/* Fixme: probably not the best place for this */
-	if ((port->type == PORT_XR17V35X) ||
-	   (port->type == PORT_XR17D15X))
-		port->handle_irq = exar_handle_irq;
-
 	register_dev_spec_attr_grp(up);
 	up->fcr = uart_config[up->port.type].fcr;
 }