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>

4 files changed, 157 insertions, 45 deletions

diff --git a/drivers/input/tablet/wacom.h b/drivers/input/tablet/wacom.h
index b4842d0e61dd..b79d45198d82 100644
--- a/drivers/input/tablet/wacom.h
+++ b/drivers/input/tablet/wacom.h
@@ -135,6 +135,6 @@ extern const struct usb_device_id wacom_ids[];
 
 void wacom_wac_irq(struct wacom_wac *wacom_wac, size_t len);
 void wacom_setup_device_quirks(struct wacom_features *features);
-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);
 #endif
diff --git a/drivers/input/tablet/wacom_sys.c b/drivers/input/tablet/wacom_sys.c
index be13223793fb..86b96f94cd84 100644
--- a/drivers/input/tablet/wacom_sys.c
+++ b/drivers/input/tablet/wacom_sys.c
@@ -317,6 +317,10 @@ static int wacom_parse_hid(struct usb_interface *intf,
                                                         /* need to reset back */
                                                         features->pktlen = WACOM_PKGLEN_TPC2FG;
                                                 }
+
+                                                if (features->type == MTSCREEN)
+                                                        features->pktlen = WACOM_PKGLEN_MTOUCH;
+
                                                 if (features->type == BAMBOO_PT) {
                                                         /* need to reset back */
                                                         features->pktlen = WACOM_PKGLEN_BBTOUCH;
@@ -349,18 +353,15 @@ static int wacom_parse_hid(struct usb_interface *intf,
                         case HID_USAGE_Y:
                                 if (usage == WCM_DESKTOP) {
                                         if (finger) {
-                                                features->device_type = BTN_TOOL_FINGER;
-                                                if (features->type == TABLETPC2FG) {
-                                                        /* need to reset back */
-                                                        features->pktlen = WACOM_PKGLEN_TPC2FG;
+                                                int type = features->type;
+
+                                                if (type == TABLETPC2FG || type == MTSCREEN) {
                                                         features->y_max =
                                                                 get_unaligned_le16(&report[i + 3]);
                                                         features->y_phy =
                                                                 get_unaligned_le16(&report[i + 6]);
                                                         i += 7;
-                                                } else if (features->type == BAMBOO_PT) {
-                                                        /* need to reset back */
-                                                        features->pktlen = WACOM_PKGLEN_BBTOUCH;
+                                                } else if (type == BAMBOO_PT) {
                                                         features->y_phy =
                                                                 get_unaligned_le16(&report[i + 3]);
                                                         features->y_max =
@@ -374,10 +375,6 @@ static int wacom_parse_hid(struct usb_interface *intf,
                                                         i += 4;
                                                 }
                                         } else if (pen) {
-                                                /* penabled only accepts exact bytes of data */
-                                                if (features->type == TABLETPC2FG)
-                                                        features->pktlen = WACOM_PKGLEN_GRAPHIRE;
-                                                features->device_type = BTN_TOOL_PEN;
                                                 features->y_max =
                                                         get_unaligned_le16(&report[i + 3]);
                                                 i += 4;
@@ -440,22 +437,29 @@ static int wacom_query_tablet_data(struct usb_interface *intf, struct wacom_feat
         if (!rep_data)
                 return error;
 
-        /* ask to report tablet data if it is MT Tablet PC or
-         * not a Tablet PC */
-        if (features->type == TABLETPC2FG) {
-                do {
-                        rep_data[0] = 3;
-                        rep_data[1] = 4;
-                        rep_data[2] = 0;
-                        rep_data[3] = 0;
-                        report_id = 3;
-                        error = wacom_set_report(intf, WAC_HID_FEATURE_REPORT,
-                                                 report_id, rep_data, 4, 1);
-                        if (error >= 0)
-                                error = wacom_get_report(intf,
-                                                WAC_HID_FEATURE_REPORT,
-                                                report_id, rep_data, 4, 1);
-                } while ((error < 0 || rep_data[1] != 4) && limit++ < WAC_MSG_RETRIES);
+        /* ask to report Wacom data */
+        if (features->device_type == BTN_TOOL_FINGER) {
+                /* if it is an MT Tablet PC touch */
+                if (features->type == TABLETPC2FG ||
+                    features->type == MTSCREEN) {
+                        do {
+                                rep_data[0] = 3;
+                                rep_data[1] = 4;
+                                rep_data[2] = 0;
+                                rep_data[3] = 0;
+                                report_id = 3;
+                                error = wacom_set_report(intf,
+                                                         WAC_HID_FEATURE_REPORT,
+                                                         report_id,
+                                                         rep_data, 4, 1);
+                                if (error >= 0)
+                                        error = wacom_get_report(intf,
+                                                        WAC_HID_FEATURE_REPORT,
+                                                        report_id,
+                                                        rep_data, 4, 1);
+                        } while ((error < 0 || rep_data[1] != 4) &&
+                                 limit++ < WAC_MSG_RETRIES);
+                }
         } else if (features->type != TABLETPC &&
                    features->type != WIRELESS &&
                    features->device_type == BTN_TOOL_PEN) {
@@ -477,7 +481,7 @@ static int wacom_query_tablet_data(struct usb_interface *intf, struct wacom_feat
 }
 
 static int wacom_retrieve_hid_descriptor(struct usb_interface *intf,
-                struct wacom_features *features)
+                                         struct wacom_features *features)
 {
         int error = 0;
         struct usb_host_interface *interface = intf->cur_altsetting;
@@ -505,10 +509,13 @@ static int wacom_retrieve_hid_descriptor(struct usb_interface *intf,
                 }
         }
 
-        /* only Tablet PCs and Bamboo P&T need to retrieve the info */
-        if ((features->type != TABLETPC) && (features->type != TABLETPC2FG) &&
-            (features->type != BAMBOO_PT))
+        /* only devices that support touch need to retrieve the info */
+        if (features->type != TABLETPC &&
+            features->type != TABLETPC2FG &&
+            features->type != BAMBOO_PT &&
+            features->type != MTSCREEN) {
                 goto out;
+        }
 
         if (usb_get_extra_descriptor(interface, HID_DEVICET_HID, &hid_desc)) {
                 if (usb_get_extra_descriptor(&interface->endpoint[0],
@@ -978,8 +985,10 @@ static int wacom_register_input(struct wacom *wacom)
         int error;
 
         input_dev = input_allocate_device();
-        if (!input_dev)
-                return -ENOMEM;
+        if (!input_dev) {
+                error = -ENOMEM;
+                goto fail1;
+        }
 
         input_dev->name = wacom_wac->name;
         input_dev->dev.parent = &intf->dev;
@@ -989,14 +998,20 @@ static int wacom_register_input(struct wacom *wacom)
         input_set_drvdata(input_dev, wacom);
 
         wacom_wac->input = input_dev;
-        wacom_setup_input_capabilities(input_dev, wacom_wac);
+        error = wacom_setup_input_capabilities(input_dev, wacom_wac);
+        if (error)
+                goto fail1;
 
         error = input_register_device(input_dev);
-        if (error) {
-                input_free_device(input_dev);
-                wacom_wac->input = NULL;
-        }
+        if (error)
+                goto fail2;
+
+        return 0;
 
+fail2:
+        input_free_device(input_dev);
+        wacom_wac->input = NULL;
+fail1:
         return error;
 }
 
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) },
diff --git a/drivers/input/tablet/wacom_wac.h b/drivers/input/tablet/wacom_wac.h
index 321269c1ac4c..78fbd3f42009 100644
--- a/drivers/input/tablet/wacom_wac.h
+++ b/drivers/input/tablet/wacom_wac.h
@@ -25,6 +25,10 @@
 #define WACOM_PKGLEN_BBTOUCH3   64
 #define WACOM_PKGLEN_BBPEN      10
 #define WACOM_PKGLEN_WIRELESS   32
+#define WACOM_PKGLEN_MTOUCH     62
+
+/* wacom data size per MT contact */
+#define WACOM_BYTES_PER_MT_PACKET       11
 
 /* device IDs */
 #define STYLUS_DEVICE_ID        0x02
@@ -41,6 +45,7 @@
 #define WACOM_REPORT_INTUOS5PAD         3
 #define WACOM_REPORT_TPC1FG             6
 #define WACOM_REPORT_TPC2FG             13
+#define WACOM_REPORT_TPCMT              13
 #define WACOM_REPORT_TPCHID             15
 #define WACOM_REPORT_TPCST              16
 
@@ -76,6 +81,7 @@ enum {
         WACOM_MO,
         TABLETPC,
         TABLETPC2FG,
+        MTSCREEN,
         MAX_TYPE
 };
 
@@ -118,6 +124,8 @@ struct wacom_wac {
         struct input_dev *input;
         int pid;
         int battery_capacity;
+        int num_contacts_left;
+        int *slots;
 };
 
 #endif