serial: core: Add big-endian iotype

Since most drivers interpret UPIO_MEM32 to mean "little-endian" and use
readl/writel to access the registers, add a parallel UPIO_MEM32BE to
request the use of big-endian MMIO accessors (ioread32be/iowrite32be).

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 9 insertions, 6 deletions

diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 5c8b8f50f787..57ca61b14670 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -2153,6 +2153,7 @@ uart_report_port(struct uart_driver *drv, struct uart_port *port)
                 break;
         case UPIO_MEM:
         case UPIO_MEM32:
+        case UPIO_MEM32BE:
         case UPIO_AU:
         case UPIO_TSI:
                 snprintf(address, sizeof(address),
@@ -2796,6 +2797,7 @@ int uart_match_port(struct uart_port *port1, struct uart_port *port2)
                        (port1->hub6   == port2->hub6);
         case UPIO_MEM:
         case UPIO_MEM32:
+        case UPIO_MEM32BE:
         case UPIO_AU:
         case UPIO_TSI:
                 return (port1->mapbase == port2->mapbase);
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 3231a43f6acf..057038cf2788 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -142,12 +142,13 @@ struct uart_port {
         unsigned char           iotype;                 /* io access style */
         unsigned char           unused1;
 
-#define UPIO_PORT               (0)
-#define UPIO_HUB6               (1)
-#define UPIO_MEM                (2)
-#define UPIO_MEM32              (3)
-#define UPIO_AU                 (4)                     /* Au1x00 and RT288x type IO */
-#define UPIO_TSI                (5)                     /* Tsi108/109 type IO */
+#define UPIO_PORT               (0)                     /* 8b I/O port access */
+#define UPIO_HUB6               (1)                     /* Hub6 ISA card */
+#define UPIO_MEM                (2)                     /* 8b MMIO access */
+#define UPIO_MEM32              (3)                     /* 32b little endian */
+#define UPIO_MEM32BE            (4)                     /* 32b big endian */
+#define UPIO_AU                 (5)                     /* Au1x00 and RT288x type IO */
+#define UPIO_TSI                (6)                     /* Tsi108/109 type IO */
 
         unsigned int            read_status_mask;       /* driver specific */
         unsigned int            ignore_status_mask;     /* driver specific */