Input: wacom - read 3rd gen Bamboo Touch HID data

Override invalid pen based pktlen and x/y_max with touch
values from HID report.

Since active area of pen and touch are same on these
devices, set physical x/y size while pen x/y_max and
resolution are still valid.

Signed-off-by: Chris Bagwell <chris@cnpbagwell.com>
Acked-by: Ping Cheng <pingc@wacom.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

2 files changed, 48 insertions, 2 deletions

diff --git a/drivers/input/tablet/wacom_sys.c b/drivers/input/tablet/wacom_sys.c
index f35ed7cb10a9..ab498e480f3b 100644
--- a/drivers/input/tablet/wacom_sys.c
+++ b/drivers/input/tablet/wacom_sys.c
@@ -28,7 +28,9 @@
 #define HID_USAGE_Y_TILT                0x3e
 #define HID_USAGE_FINGER                0x22
 #define HID_USAGE_STYLUS                0x20
-#define HID_COLLECTION                  0xc0
+#define HID_COLLECTION                  0xa1
+#define HID_COLLECTION_LOGICAL          0x02
+#define HID_COLLECTION_END              0xc0
 
 enum {
         WCM_UNDEFINED = 0,
@@ -165,6 +167,35 @@ static void wacom_close(struct input_dev *dev)
                 usb_autopm_put_interface(wacom->intf);
 }
 
+static int wacom_parse_logical_collection(unsigned char *report,
+                                          struct wacom_features *features)
+{
+        int length = 0;
+
+        if (features->type == BAMBOO_PT) {
+
+                /* Logical collection is only used by 3rd gen Bamboo Touch */
+                features->pktlen = WACOM_PKGLEN_BBTOUCH3;
+                features->device_type = BTN_TOOL_DOUBLETAP;
+
+                /*
+                 * Stylus and Touch have same active area
+                 * so compute physical size based on stylus
+                 * data before its overwritten.
+                 */
+                features->x_phy =
+                        (features->x_max * features->x_resolution) / 100;
+                features->y_phy =
+                        (features->y_max * features->y_resolution) / 100;
+
+                features->x_max = features->y_max =
+                        get_unaligned_le16(&report[10]);
+
+                length = 11;
+        }
+        return length;
+}
+
 /*
  * Interface Descriptor of wacom devices can be incomplete and
  * inconsistent so wacom_features table is used to store stylus
@@ -193,6 +224,10 @@ static void wacom_close(struct input_dev *dev)
  * X/Y maximum as well as the physical size of tablet. Since touch
  * interfaces haven't supported pressure or distance, this is enough
  * information to override invalid values in the wacom_features table.
+ *
+ * 3rd gen Bamboo Touch no longer define a Digitizer-Finger Pysical
+ * Collection. Instead they define a Logical Collection with a single
+ * Logical Maximum for both X and Y.
  */
 static int wacom_parse_hid(struct usb_interface *intf,
                            struct hid_descriptor *hid_desc,
@@ -355,10 +390,20 @@ static int wacom_parse_hid(struct usb_interface *intf,
                         }
                         break;
 
-                case HID_COLLECTION:
+                case HID_COLLECTION_END:
                         /* reset UsagePage and Finger */
                         finger = usage = 0;
                         break;
+
+                case HID_COLLECTION:
+                        i++;
+                        switch (report[i]) {
+                        case HID_COLLECTION_LOGICAL:
+                                i += wacom_parse_logical_collection(&report[i],
+                                                                    features);
+                                break;
+                        }
+                        break;
                 }
         }
 
diff --git a/drivers/input/tablet/wacom_wac.h b/drivers/input/tablet/wacom_wac.h
index 53eb71b68330..af94e6d9d6a9 100644
--- a/drivers/input/tablet/wacom_wac.h
+++ b/drivers/input/tablet/wacom_wac.h
@@ -22,6 +22,7 @@
 #define WACOM_PKGLEN_TPC1FG      5
 #define WACOM_PKGLEN_TPC2FG     14
 #define WACOM_PKGLEN_BBTOUCH    20
+#define WACOM_PKGLEN_BBTOUCH3   64
 
 /* device IDs */
 #define STYLUS_DEVICE_ID        0x02