usb/misc/usbled: Add Riso Kagaku Webmail Notifier

Add support for the "Webmail Notifier" (USB powered LED for signaling
new emails) made by Riso Kagaku Corp. which displays 7 distinct colors.

USB Protocol initially reverse engineered by
	https://code.google.com/p/usbmailnotifier/.
Signed-off-by: Christian Vogel <vogelchr@vogel.cx>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/misc/usbled.c

@@ -22,8 +22,27 @@
 enum led_type {
 	DELCOM_VISUAL_SIGNAL_INDICATOR,
 	DREAM_CHEEKY_WEBMAIL_NOTIFIER,
+	RISO_KAGAKU_LED
 };
 
+/* the Webmail LED made by RISO KAGAKU CORP. decodes a color index
+   internally, we want to keep the red+green+blue sysfs api, so we decode
+   from 1-bit RGB to the riso kagaku color index according to this table... */
+
+static unsigned const char riso_kagaku_tbl[] = {
+/* R+2G+4B -> riso kagaku color index */
+	[0] = 0, /* black   */
+	[1] = 2, /* red     */
+	[2] = 1, /* green   */
+	[3] = 5, /* yellow  */
+	[4] = 3, /* blue    */
+	[5] = 6, /* magenta */
+	[6] = 4, /* cyan    */
+	[7] = 7  /* white   */
+};
+
+#define RISO_KAGAKU_IX(r,g,b) riso_kagaku_tbl[((r)?1:0)+((g)?2:0)+((b)?4:0)]
+
 /* table of devices that work with this driver */
 static const struct usb_device_id id_table[] = {
 	{ USB_DEVICE(0x0fc5, 0x1223),
@@ -32,6 +51,8 @@ static const struct usb_device_id id_table[] = {
 			.driver_info = DREAM_CHEEKY_WEBMAIL_NOTIFIER },
 	{ USB_DEVICE(0x1d34, 0x000a),
 			.driver_info = DREAM_CHEEKY_WEBMAIL_NOTIFIER },
+	{ USB_DEVICE(0x1294, 0x1320),
+			.driver_info = RISO_KAGAKU_LED },
 	{ },
 };
 MODULE_DEVICE_TABLE(usb, id_table);
@@ -48,6 +69,7 @@ static void change_color(struct usb_led *led)
 {
 	int retval = 0;
 	unsigned char *buffer;
+	int actlength;
 
 	buffer = kmalloc(8, GFP_KERNEL);
 	if (!buffer) {
@@ -104,6 +126,18 @@ static void change_color(struct usb_led *led)
 					2000);
 		break;
 
+	case RISO_KAGAKU_LED:
+		buffer[0] = RISO_KAGAKU_IX(led->red, led->green, led->blue);
+		buffer[1] = 0;
+		buffer[2] = 0;
+		buffer[3] = 0;
+		buffer[4] = 0;
+
+		retval = usb_interrupt_msg(led->udev,
+			usb_sndctrlpipe(led->udev, 2),
+			buffer, 5, &actlength, 1000 /*ms timeout*/);
+		break;
+
 	default:
 		dev_err(&led->udev->dev, "unknown device type %d\n", led->type);
 	}