[USB]Add Samsung SGH-I500/Android modem ID switch to visor driver

[Maciej Szmigiero <mhej@o2.pl>]

[USB]Add Samsung SGH-I500/Android modem ID switch to visor driver

Samsung decided to reuse USB ID of its old CDMA phone SGH-I500 for the
modem part of some of their Android phones. At least Galaxy Spica
is affected.

This modem needs ACM driver and does not work with visor driver which
binds the conflicting ID for SGH-I500.
Because SGH-I500 is pretty an old hardware its best to add switch to visor
driver in cause somebody still wants to use that phone with Linux.

Note that this is needed only when using the Android phone as modem,
not in USB storage or ADB mode.

Signed-off-by: Maciej Szmigiero <mhej@o2.pl>

diff --git a/drivers/usb/serial/visor.c b/drivers/usb/serial/visor.c
index 15a5d89..5e56ab3 100644
--- a/drivers/usb/serial/visor.c
+++ b/drivers/usb/serial/visor.c
@@ -52,6 +52,7 @@ static int palm_os_4_probe(struct usb_serial *serial,
 
 /* Parameters that may be passed into the module. */
 static int debug;
+static int enable_i500;
 static __u16 vendor;
 static __u16 product;
 
@@ -479,6 +480,10 @@ static int visor_probe(struct usb_serial *serial,
 
 	dbg("%s", __func__);
 
+	if ((!enable_i500) && (id->idVendor == SAMSUNG_VENDOR_ID) &&
+		(id->idProduct == SAMSUNG_SPH_I500_ID))
+		return -ENODEV;
+
 	if (serial->dev->actconfig->desc.bConfigurationValue != 1) {
 		dev_err(&serial->dev->dev, "active config #%d != 1 ??\n",
 			serial->dev->actconfig->desc.bConfigurationValue);
@@ -718,6 +723,11 @@ MODULE_LICENSE("GPL");
 module_param(debug, bool, S_IRUGO | S_IWUSR);
 MODULE_PARM_DESC(debug, "Debug enabled or not");
 
+module_param(enable_i500, bool, S_IRUGO);
+MODULE_PARM_DESC(enable_i500, "Enable support for Samsung SPH-I500. "
+				"Causes USBID conflict with modem in Samsung "
+				"Android phones");
+
 module_param(vendor, ushort, 0);
 MODULE_PARM_DESC(vendor, "User specified vendor ID");
 module_param(product, ushort, 0);