HID: proper LED-mapping for SpaceNavigator

This change introduces a mapping for LED indicators between the HID
specification and the Linux input subsystem. The previous code properly
mapped the LEDs relevant for Keyboards, but garbeled the remaining ones.
With this change all LED enums from the input system get mapped to more
or less equivalent LED numbers from the HID specification.

This patch also ensures that the unused bits in a HID report to the
device are zeroed out. This makes the 3Dconnexion SpaceNavigator fully
usable with the linux input system.

Signed-off-by: Simon Budig <simon@budig.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/hid-core.c

@@ -880,6 +880,10 @@ static void hid_output_field(struct hid_field *field, __u8 *data)
 	unsigned size = field->report_size;
 	unsigned n;
 
+	/* make sure the unused bits in the last byte are zeros */
+	if (count > 0 && size > 0)
+		data[(count*size-1)/8] = 0;
+
 	for (n = 0; n < count; n++) {
 		if (field->logical_minimum < 0)	/* signed values */
 			implement(data, offset + n * size, size, s32ton(field->value[n], size));

drivers/hid/hid-input.c

@@ -364,9 +364,22 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel
 			break;
 
 		case HID_UP_LED:
-			if (((usage->hid - 1) & 0xffff) >= LED_MAX)
-				goto ignore;
-			map_led((usage->hid - 1) & 0xffff);
+
+			switch (usage->hid & 0xffff) {                        /* HID-Value:                   */
+				case 0x01:  map_led (LED_NUML);     break;    /*   "Num Lock"                 */
+				case 0x02:  map_led (LED_CAPSL);    break;    /*   "Caps Lock"                */
+				case 0x03:  map_led (LED_SCROLLL);  break;    /*   "Scroll Lock"              */
+				case 0x04:  map_led (LED_COMPOSE);  break;    /*   "Compose"                  */
+				case 0x05:  map_led (LED_KANA);     break;    /*   "Kana"                     */
+				case 0x27:  map_led (LED_SLEEP);    break;    /*   "Stand-By"                 */
+				case 0x4c:  map_led (LED_SUSPEND);  break;    /*   "System Suspend"           */
+				case 0x09:  map_led (LED_MUTE);     break;    /*   "Mute"                     */
+				case 0x4b:  map_led (LED_MISC);     break;    /*   "Generic Indicator"        */
+				case 0x19:  map_led (LED_MAIL);     break;    /*   "Message Waiting"          */
+				case 0x4d:  map_led (LED_CHARGING); break;    /*   "External Power Connected" */
+
+				default: goto ignore;
+			}
 			break;
 
 		case HID_UP_DIGITIZER: