[PATCH] [media] winbond-cir: Fix initialization

[Sean Young <sean@mess.org>]

The serial driver will detect the winbond cir device as a serial port,
since it looks exactly like a serial port unless you know what it is
from the PNP ID.

Winbond CIR 00:04: Region 0x2f8-0x2ff already in use!
Winbond CIR 00:04: disabled
Winbond CIR: probe of 00:04 failed with error -16

Signed-off-by: Sean Young <sean@mess.org>
---
 drivers/media/rc/winbond-cir.c | 21 ++++++++++++++++++++-
 drivers/tty/serial/8250/8250.c |  1 +
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/drivers/media/rc/winbond-cir.c b/drivers/media/rc/winbond-cir.c
index 54ee348..20a0bbb 100644
--- a/drivers/media/rc/winbond-cir.c
+++ b/drivers/media/rc/winbond-cir.c
@@ -55,6 +55,7 @@
 #include <linux/slab.h>
 #include <linux/wait.h>
 #include <linux/sched.h>
+#include <linux/serial_8250.h>
 #include <media/rc-core.h>
 
 #define DRVNAME "winbond-cir"
@@ -957,6 +958,7 @@ wbcir_probe(struct pnp_dev *device, const struct pnp_device_id *dev_id)
 	struct device *dev = &device->dev;
 	struct wbcir_data *data;
 	int err;
+	struct resource *io;
 
 	if (!(pnp_port_len(device, 0) == EHFUNC_IOMEM_LEN &&
 	      pnp_port_len(device, 1) == WAKEUP_IOMEM_LEN &&
@@ -1049,7 +1051,24 @@ wbcir_probe(struct pnp_dev *device, const struct pnp_device_id *dev_id)
 		goto exit_release_wbase;
 	}
 
-	if (!request_region(data->sbase, SP_IOMEM_LEN, DRVNAME)) {
+	io = request_region(data->sbase, SP_IOMEM_LEN, DRVNAME);
+
+	/*
+	 * The winbond cir device looks exactly like an NS16550A serial port
+	 * unless you know what it is. We've got here via the PNP ID.
+	 */
+#ifdef CONFIG_SERIAL_8250
+	if (!io) {
+		struct uart_port port = { .iobase = data->sbase };
+		int line = serial8250_find_port(&port);
+		if (line >= 0) {
+			serial8250_unregister_port(line);
+
+			io = request_region(data->sbase, SP_IOMEM_LEN, DRVNAME);
+		}
+	}
+#endif
+	if (!io) {
 		dev_err(dev, "Region 0x%lx-0x%lx already in use!\n",
 			data->sbase, data->sbase + SP_IOMEM_LEN - 1);
 		err = -EBUSY;
diff --git a/drivers/tty/serial/8250/8250.c b/drivers/tty/serial/8250/8250.c
index 5c27f7e..d38615f 100644
--- a/drivers/tty/serial/8250/8250.c
+++ b/drivers/tty/serial/8250/8250.c
@@ -2914,6 +2914,7 @@ int serial8250_find_port(struct uart_port *p)
 	}
 	return -ENODEV;
 }
+EXPORT_SYMBOL(serial8250_find_port);
 
 #define SERIAL8250_CONSOLE	&serial8250_console
 #else
-- 
1.7.11.2