tty: serial core: decouple pm states from ACPI

The serial core is using power states lifted from ACPI for no
good reason. Remove this reference from the documentation and
alter all users to use an enum specific to the serial core
instead, and define it in <linux/serial_core.h>.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 13 insertions, 1 deletions

diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index c6690a2a27fb..a116daa13113 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -208,13 +208,25 @@ static inline void serial_port_out(struct uart_port *up, int offset, int value)
 	up->serial_out(up, offset, value);
 }
 
+/**
+ * enum uart_pm_state - power states for UARTs
+ * @UART_PM_STATE_ON: UART is powered, up and operational
+ * @UART_PM_STATE_OFF: UART is powered off
+ * @UART_PM_STATE_UNDEFINED: sentinel
+ */
+enum uart_pm_state {
+	UART_PM_STATE_ON = 0,
+	UART_PM_STATE_OFF = 3, /* number taken from ACPI */
+	UART_PM_STATE_UNDEFINED,
+};
+
 /*
  * This is the state information which is persistent across opens.
  */
 struct uart_state {
 	struct tty_port		port;
 
-	int			pm_state;
+	enum uart_pm_state	pm_state;
 	struct circ_buf		xmit;
 
 	struct uart_port	*uart_port;