serial: 8250_of: Add IO space support

Currently the 8250_of driver only supports MEM IO type
accesses.

Some development boards (Huawei D03, specifically) require
IO space access for 8250-compatible OF driver support, so
add it.

The modification is quite simple: just set the port iotype
and associated flags depending on the device address
resource type.

Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c
index 3de8d6a412462097cbc845bbd690da18daa09b04..bfb37f0be22f2e5e732c1b18153d45a137b7ff13 100644 (file)
--- a/drivers/tty/serial/8250/8250_of.c
+++ b/drivers/tty/serial/8250/8250_of.c
@@ -92,13 +92,43 @@ static int of_platform_serial_setup(struct platform_device *ofdev,
                goto err_unprepare;
        }
 
+       port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_FIXED_PORT |
+                                 UPF_FIXED_TYPE;
        spin_lock_init(&port->lock);
-       port->mapbase = resource.start;
-       port->mapsize = resource_size(&resource);
 
-       /* Check for shifted address mapping */
-       if (of_property_read_u32(np, "reg-offset", &prop) == 0)
-               port->mapbase += prop;
+       if (resource_type(&resource) == IORESOURCE_IO) {
+               port->iotype = UPIO_PORT;
+               port->iobase = resource.start;
+       } else {
+               port->mapbase = resource.start;
+               port->mapsize = resource_size(&resource);
+
+               /* Check for shifted address mapping */
+               if (of_property_read_u32(np, "reg-offset", &prop) == 0)
+                       port->mapbase += prop;
+
+               port->iotype = UPIO_MEM;
+               if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
+                       switch (prop) {
+                       case 1:
+                               port->iotype = UPIO_MEM;
+                               break;
+                       case 2:
+                               port->iotype = UPIO_MEM16;
+                               break;
+                       case 4:
+                               port->iotype = of_device_is_big_endian(np) ?
+                                              UPIO_MEM32BE : UPIO_MEM32;
+                               break;
+                       default:
+                               dev_warn(&ofdev->dev, "unsupported reg-io-width (%d)\n",
+                                        prop);
+                               ret = -EINVAL;
+                               goto err_dispose;
+                       }
+               }
+               port->flags |= UPF_IOREMAP;
+       }
 
        /* Check for registers offset within the devices address range */
        if (of_property_read_u32(np, "reg-shift", &prop) == 0)
@@ -114,26 +144,6 @@ static int of_platform_serial_setup(struct platform_device *ofdev,
                port->line = ret;
 
        port->irq = irq_of_parse_and_map(np, 0);
-       port->iotype = UPIO_MEM;
-       if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
-               switch (prop) {
-               case 1:
-                       port->iotype = UPIO_MEM;
-                       break;
-               case 2:
-                       port->iotype = UPIO_MEM16;
-                       break;
-               case 4:
-                       port->iotype = of_device_is_big_endian(np) ?
-                                      UPIO_MEM32BE : UPIO_MEM32;
-                       break;
-               default:
-                       dev_warn(&ofdev->dev, "unsupported reg-io-width (%d)\n",
-                                prop);
-                       ret = -EINVAL;
-                       goto err_dispose;
-               }
-       }
 
        info->rst = devm_reset_control_get_optional_shared(&ofdev->dev, NULL);
        if (IS_ERR(info->rst)) {
@@ -147,8 +157,6 @@ static int of_platform_serial_setup(struct platform_device *ofdev,
 
        port->type = type;
        port->uartclk = clk;
-       port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_IOREMAP
-               | UPF_FIXED_PORT | UPF_FIXED_TYPE;
        port->irqflags |= IRQF_SHARED;
 
        if (of_property_read_bool(np, "no-loopback-test"))