HID: asus: Add T100CHI bluetooth keyboard dock special keys mapping

The Asus Transformer T100CHI comes with a Bluetooth keyboard dock which
uses the same 0xff31 Asus vendor HUT page as other Asus keyboards.

This commit adds its device-id to hid-asus and fixes an issue in the
descriptor of the 0xff31 Usage, which together fixes the special keys
on this keyboard not working.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 27 insertions, 0 deletions

diff --git a/drivers/hid/hid-asus.c b/drivers/hid/hid-asus.c
index b2501b64ab9d..43fb4a331cf3 100644
--- a/drivers/hid/hid-asus.c
+++ b/drivers/hid/hid-asus.c
@@ -65,6 +65,7 @@ MODULE_DESCRIPTION("Asus HID Keyboard and TouchPad");
 #define QUIRK_NO_CONSUMER_USAGES        BIT(4)
 #define QUIRK_USE_KBD_BACKLIGHT         BIT(5)
 #define QUIRK_T100_KEYBOARD             BIT(6)
+#define QUIRK_T100CHI                   BIT(7)
 
 #define I2C_KEYBOARD_QUIRKS                     (QUIRK_FIX_NOTEBOOK_REPORT | \
                                                  QUIRK_NO_INIT_REPORTS | \
@@ -619,11 +620,34 @@ static __u8 *asus_report_fixup(struct hid_device *hdev, __u8 *rdesc,
                 hid_info(hdev, "Fixing up Asus notebook report descriptor\n");
                 rdesc[55] = 0xdd;
         }
+        /* For the T100TA keyboard dock */
         if (drvdata->quirks & QUIRK_T100_KEYBOARD &&
                  *rsize == 76 && rdesc[73] == 0x81 && rdesc[74] == 0x01) {
                 hid_info(hdev, "Fixing up Asus T100 keyb report descriptor\n");
                 rdesc[74] &= ~HID_MAIN_ITEM_CONSTANT;
         }
+        /* For the T100CHI keyboard dock */
+        if (drvdata->quirks & QUIRK_T100CHI &&
+                 *rsize == 403 && rdesc[388] == 0x09 && rdesc[389] == 0x76) {
+                /*
+                 * Change Usage (76h) to Usage Minimum (00h), Usage Maximum
+                 * (FFh) and clear the flags in the Input() byte.
+                 * Note the descriptor has a bogus 0 byte at the end so we
+                 * only need 1 extra byte.
+                 */
+                *rsize = 404;
+                rdesc = kmemdup(rdesc, *rsize, GFP_KERNEL);
+                if (!rdesc)
+                        return NULL;
+
+                hid_info(hdev, "Fixing up T100CHI keyb report descriptor\n");
+                memmove(rdesc + 392, rdesc + 390, 12);
+                rdesc[388] = 0x19;
+                rdesc[389] = 0x00;
+                rdesc[390] = 0x29;
+                rdesc[391] = 0xff;
+                rdesc[402] = 0x00;
+        }
 
         return rdesc;
 }
@@ -643,6 +667,9 @@ static const struct hid_device_id asus_devices[] = {
         { HID_USB_DEVICE(USB_VENDOR_ID_CHICONY, USB_DEVICE_ID_ASUS_AK1D) },
         { HID_USB_DEVICE(USB_VENDOR_ID_TURBOX, USB_DEVICE_ID_ASUS_MD_5110) },
         { HID_USB_DEVICE(USB_VENDOR_ID_JESS, USB_DEVICE_ID_ASUS_MD_5112) },
+        { HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ASUSTEK,
+                USB_DEVICE_ID_ASUSTEK_T100CHI_KEYBOARD), QUIRK_T100CHI },
+
         { }
 };
 MODULE_DEVICE_TABLE(hid, asus_devices);