Input: wacom - add 0xE5 (MT device) support

Main part of patch is adding support for a new Wacom MT touch
packet and labels these devices using MTSCREEN type.

Other items of interest:

Delete some duplicate code in HID parsing for Y info since
its already done in X path.

In wacom_query_tablet_data(), only invoke the set report
that requests tablets to send Wacom Touch packets for
Finger interfaces.  Mostly, this is to make code intent clear.

Tested-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Chris Bagwell <chris@cnpbagwell.com>
Signed-off-by: Ping Cheng <pingc@wacom.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1 files changed, 94 insertions, 5 deletions

diff --git a/drivers/input/tablet/wacom_wac.c b/drivers/input/tablet/wacom_wac.c
index e5cd0e57d178..10e5cf870359 100644
--- a/drivers/input/tablet/wacom_wac.c
+++ b/drivers/input/tablet/wacom_wac.c
@@ -768,6 +768,72 @@ static int wacom_intuos_irq(struct wacom_wac *wacom)
         return 1;
 }
 
+static int find_slot_from_contactid(struct wacom_wac *wacom, int contactid)
+{
+        int touch_max = wacom->features.touch_max;
+        int i;
+
+        if (!wacom->slots)
+                return -1;
+
+        for (i = 0; i < touch_max; ++i) {
+                if (wacom->slots[i] == contactid)
+                        return i;
+        }
+        for (i = 0; i < touch_max; ++i) {
+                if (wacom->slots[i] == -1)
+                        return i;
+        }
+        return -1;
+}
+
+static int wacom_mt_touch(struct wacom_wac *wacom)
+{
+        struct input_dev *input = wacom->input;
+        char *data = wacom->data;
+        int i;
+        int current_num_contacts = data[2];
+        int contacts_to_send = 0;
+
+        /*
+         * First packet resets the counter since only the first
+         * packet in series will have non-zero current_num_contacts.
+         */
+        if (current_num_contacts)
+                wacom->num_contacts_left = current_num_contacts;
+
+        /* There are at most 5 contacts per packet */
+        contacts_to_send = min(5, wacom->num_contacts_left);
+
+        for (i = 0; i < contacts_to_send; i++) {
+                int offset = (WACOM_BYTES_PER_MT_PACKET * i) + 3;
+                bool touch = data[offset] & 0x1;
+                int id = le16_to_cpup((__le16 *)&data[offset + 1]);
+                int slot = find_slot_from_contactid(wacom, id);
+
+                if (slot < 0)
+                        continue;
+
+                input_mt_slot(input, slot);
+                input_mt_report_slot_state(input, MT_TOOL_FINGER, touch);
+                if (touch) {
+                        int x = le16_to_cpup((__le16 *)&data[offset + 7]);
+                        int y = le16_to_cpup((__le16 *)&data[offset + 9]);
+                        input_report_abs(input, ABS_MT_POSITION_X, x);
+                        input_report_abs(input, ABS_MT_POSITION_Y, y);
+                }
+                wacom->slots[slot] = touch ? id : -1;
+        }
+
+        input_mt_report_pointer_emulation(input, true);
+
+        wacom->num_contacts_left -= contacts_to_send;
+        if (wacom->num_contacts_left < 0)
+                wacom->num_contacts_left = 0;
+
+        return 1;
+}
+
 static int wacom_tpc_mt_touch(struct wacom_wac *wacom)
 {
         struct input_dev *input = wacom->input;
@@ -806,6 +872,9 @@ static int wacom_tpc_single_touch(struct wacom_wac *wacom, size_t len)
         bool prox;
         int x = 0, y = 0;
 
+        if (wacom->features.touch_max > 1 || len > WACOM_PKGLEN_TPC2FG)
+                return 0;
+
         if (!wacom->shared->stylus_in_proximity) {
                 if (len == WACOM_PKGLEN_TPC1FG) {
                         prox = data[0] & 0x01;
@@ -873,10 +942,10 @@ static int wacom_tpc_irq(struct wacom_wac *wacom, size_t len)
 
         switch (len) {
         case WACOM_PKGLEN_TPC1FG:
-                 return wacom_tpc_single_touch(wacom, len);
+                return wacom_tpc_single_touch(wacom, len);
 
         case WACOM_PKGLEN_TPC2FG:
-                return wacom_tpc_mt_touch(wacom);
+                return wacom_tpc_mt_touch(wacom);
 
         default:
                 switch (data[0]) {
@@ -885,6 +954,9 @@ static int wacom_tpc_irq(struct wacom_wac *wacom, size_t len)
                 case WACOM_REPORT_TPCST:
                         return wacom_tpc_single_touch(wacom, len);
 
+                case WACOM_REPORT_TPCMT:
+                        return wacom_mt_touch(wacom);
+
                 case WACOM_REPORT_PENABLED:
                         return wacom_tpc_pen(wacom);
                 }
@@ -1164,6 +1236,7 @@ void wacom_wac_irq(struct wacom_wac *wacom_wac, size_t len)
 
         case TABLETPC:
         case TABLETPC2FG:
+        case MTSCREEN:
                 sync = wacom_tpc_irq(wacom_wac, len);
                 break;
 
@@ -1237,7 +1310,8 @@ void wacom_setup_device_quirks(struct wacom_features *features)
         /* these device have multiple inputs */
         if (features->type == TABLETPC || features->type == TABLETPC2FG ||
             features->type == BAMBOO_PT || features->type == WIRELESS ||
-            (features->type >= INTUOS5S && features->type <= INTUOS5L))
+            (features->type >= INTUOS5S && features->type <= INTUOS5L) ||
+            features->type == MTSCREEN)
                 features->quirks |= WACOM_QUIRK_MULTI_INPUT;
 
         /* quirk for bamboo touch with 2 low res touches */
@@ -1268,8 +1342,8 @@ static unsigned int wacom_calculate_touch_res(unsigned int logical_max,
        return (logical_max * 100) / physical_max;
 }
 
-void wacom_setup_input_capabilities(struct input_dev *input_dev,
-                                    struct wacom_wac *wacom_wac)
+int wacom_setup_input_capabilities(struct input_dev *input_dev,
+                                   struct wacom_wac *wacom_wac)
 {
         struct wacom_features *features = &wacom_wac->features;
         int i;
@@ -1465,8 +1539,18 @@ void wacom_setup_input_capabilities(struct input_dev *input_dev,
                 break;
 
         case TABLETPC2FG:
+        case MTSCREEN:
                 if (features->device_type == BTN_TOOL_FINGER) {
 
+                        wacom_wac->slots = kmalloc(features->touch_max *
+                                                        sizeof(int),
+                                                   GFP_KERNEL);
+                        if (!wacom_wac->slots)
+                                return -ENOMEM;
+
+                        for (i = 0; i < features->touch_max; i++)
+                                wacom_wac->slots[i] = -1;
+
                         input_mt_init_slots(input_dev, features->touch_max);
                         input_set_abs_params(input_dev, ABS_MT_TOOL_TYPE,
                                         0, MT_TOOL_MAX, 0, 0);
@@ -1552,6 +1636,7 @@ void wacom_setup_input_capabilities(struct input_dev *input_dev,
                 }
                 break;
         }
+        return 0;
 }
 
 static const struct wacom_features wacom_features_0x00 =
@@ -1784,6 +1869,9 @@ static const struct wacom_features wacom_features_0xE3 =
         { "Wacom ISDv4 E3",       WACOM_PKGLEN_TPC2FG,    26202, 16325,  255,
           0, TABLETPC2FG, WACOM_INTUOS_RES, WACOM_INTUOS_RES,
           .touch_max = 2 };
+static const struct wacom_features wacom_features_0xE5 =
+        { "Wacom ISDv4 E5",       WACOM_PKGLEN_MTOUCH,    26202, 16325,  255,
+          0, MTSCREEN, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
 static const struct wacom_features wacom_features_0xE6 =
         { "Wacom ISDv4 E6",       WACOM_PKGLEN_TPC2FG,    27760, 15694,  255,
           0, TABLETPC2FG, WACOM_INTUOS_RES, WACOM_INTUOS_RES,
@@ -1962,6 +2050,7 @@ const struct usb_device_id wacom_ids[] = {
         { USB_DEVICE_WACOM(0x9F) },
         { USB_DEVICE_WACOM(0xE2) },
         { USB_DEVICE_WACOM(0xE3) },
+        { USB_DEVICE_WACOM(0xE5) },
         { USB_DEVICE_WACOM(0xE6) },
         { USB_DEVICE_WACOM(0xEC) },
         { USB_DEVICE_WACOM(0x47) },