HID: wacom: rely on actual touch down count to decide touch_down

touch_down is a flag to indicate if there are touches on tablet
or not. Since one set of touch events may be posted over more
than one data packet/touch frame, and pen may come in proximity
while touch events are partially sent, counting all touch events
for the set reflects the actual status of touch_down.

Signed-off-by: Ping Cheng <pingc@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 43 insertions, 32 deletions

diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c
index 69827c928e50..cf767419cdc4 100644
--- a/drivers/hid/wacom_wac.c
+++ b/drivers/hid/wacom_wac.c
@@ -1046,27 +1046,28 @@ static int wacom_24hdt_irq(struct wacom_wac *wacom)
         struct input_dev *input = wacom->input;
         unsigned char *data = wacom->data;
         int i;
-        int current_num_contacts = 0;
+        int current_num_contacts = data[61];
         int contacts_to_send = 0;
         int num_contacts_left = 4; /* maximum contacts per packet */
         int byte_per_packet = WACOM_BYTES_PER_24HDT_PACKET;
         int y_offset = 2;
+        static int contact_with_no_pen_down_count = 0;
 
         if (wacom->features.type == WACOM_27QHDT) {
                 current_num_contacts = data[63];
                 num_contacts_left = 10;
                 byte_per_packet = WACOM_BYTES_PER_QHDTHID_PACKET;
                 y_offset = 0;
-        } else {
-                current_num_contacts = data[61];
         }
 
         /*
          * First packet resets the counter since only the first
          * packet in series will have non-zero current_num_contacts.
          */
-        if (current_num_contacts)
+        if (current_num_contacts) {
                 wacom->num_contacts_left = current_num_contacts;
+                contact_with_no_pen_down_count = 0;
+        }
 
         contacts_to_send = min(num_contacts_left, wacom->num_contacts_left);
 
@@ -1099,15 +1100,16 @@ static int wacom_24hdt_irq(struct wacom_wac *wacom)
                                 input_report_abs(input, ABS_MT_WIDTH_MINOR, min(w, h));
                                 input_report_abs(input, ABS_MT_ORIENTATION, w > h);
                         }
+                        contact_with_no_pen_down_count++;
                 }
         }
         input_mt_report_pointer_emulation(input, true);
 
         wacom->num_contacts_left -= contacts_to_send;
-        if (wacom->num_contacts_left <= 0)
+        if (wacom->num_contacts_left <= 0) {
                 wacom->num_contacts_left = 0;
-
-        wacom->shared->touch_down = (wacom->num_contacts_left > 0);
+                wacom->shared->touch_down = (contact_with_no_pen_down_count > 0);
+        }
         return 1;
 }
 
@@ -1119,6 +1121,7 @@ static int wacom_mt_touch(struct wacom_wac *wacom)
         int current_num_contacts = data[2];
         int contacts_to_send = 0;
         int x_offset = 0;
+        static int contact_with_no_pen_down_count = 0;
 
         /* MTTPC does not support Height and Width */
         if (wacom->features.type == MTTPC || wacom->features.type == MTTPC_B)
@@ -1128,8 +1131,10 @@ static int wacom_mt_touch(struct wacom_wac *wacom)
          * First packet resets the counter since only the first
          * packet in series will have non-zero current_num_contacts.
          */
-        if (current_num_contacts)
+        if (current_num_contacts) {
                 wacom->num_contacts_left = current_num_contacts;
+                contact_with_no_pen_down_count = 0;
+        }
 
         /* There are at most 5 contacts per packet */
         contacts_to_send = min(5, wacom->num_contacts_left);
@@ -1150,15 +1155,16 @@ static int wacom_mt_touch(struct wacom_wac *wacom)
                         int y = get_unaligned_le16(&data[offset + x_offset + 9]);
                         input_report_abs(input, ABS_MT_POSITION_X, x);
                         input_report_abs(input, ABS_MT_POSITION_Y, y);
+                        contact_with_no_pen_down_count++;
                 }
         }
         input_mt_report_pointer_emulation(input, true);
 
         wacom->num_contacts_left -= contacts_to_send;
-        if (wacom->num_contacts_left < 0)
+        if (wacom->num_contacts_left <= 0) {
                 wacom->num_contacts_left = 0;
-
-        wacom->shared->touch_down = (wacom->num_contacts_left > 0);
+                wacom->shared->touch_down = (contact_with_no_pen_down_count > 0);
+        }
         return 1;
 }
 
@@ -1196,29 +1202,25 @@ static int wacom_tpc_single_touch(struct wacom_wac *wacom, size_t len)
 {
         unsigned char *data = wacom->data;
         struct input_dev *input = wacom->input;
-        bool prox;
+        bool prox = !wacom->shared->stylus_in_proximity;
         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;
-                        x = get_unaligned_le16(&data[1]);
-                        y = get_unaligned_le16(&data[3]);
-                } else if (len == WACOM_PKGLEN_TPC1FG_B) {
-                        prox = data[2] & 0x01;
-                        x = get_unaligned_le16(&data[3]);
-                        y = get_unaligned_le16(&data[5]);
-                } else {
-                        prox = data[1] & 0x01;
-                        x = le16_to_cpup((__le16 *)&data[2]);
-                        y = le16_to_cpup((__le16 *)&data[4]);
-                }
-        } else
-                /* force touch out when pen is in prox */
-                prox = 0;
+        if (len == WACOM_PKGLEN_TPC1FG) {
+                prox = prox && (data[0] & 0x01);
+                x = get_unaligned_le16(&data[1]);
+                y = get_unaligned_le16(&data[3]);
+        } else if (len == WACOM_PKGLEN_TPC1FG_B) {
+                prox = prox && (data[2] & 0x01);
+                x = get_unaligned_le16(&data[3]);
+                y = get_unaligned_le16(&data[5]);
+        } else {
+                prox = prox && (data[1] & 0x01);
+                x = le16_to_cpup((__le16 *)&data[2]);
+                y = le16_to_cpup((__le16 *)&data[4]);
+        }
 
         if (prox) {
                 input_report_abs(input, ABS_X, x);
@@ -1616,6 +1618,7 @@ static int wacom_bpt_touch(struct wacom_wac *wacom)
         struct input_dev *pad_input = wacom->pad_input;
         unsigned char *data = wacom->data;
         int i;
+        int contact_with_no_pen_down_count = 0;
 
         if (data[0] != 0x02)
             return 0;
@@ -1643,6 +1646,7 @@ static int wacom_bpt_touch(struct wacom_wac *wacom)
                         }
                         input_report_abs(input, ABS_MT_POSITION_X, x);
                         input_report_abs(input, ABS_MT_POSITION_Y, y);
+                        contact_with_no_pen_down_count++;
                 }
         }
 
@@ -1652,11 +1656,12 @@ static int wacom_bpt_touch(struct wacom_wac *wacom)
         input_report_key(pad_input, BTN_FORWARD, (data[1] & 0x04) != 0);
         input_report_key(pad_input, BTN_BACK, (data[1] & 0x02) != 0);
         input_report_key(pad_input, BTN_RIGHT, (data[1] & 0x01) != 0);
+        wacom->shared->touch_down = (contact_with_no_pen_down_count > 0);
 
         return 1;
 }
 
-static void wacom_bpt3_touch_msg(struct wacom_wac *wacom, unsigned char *data)
+static int wacom_bpt3_touch_msg(struct wacom_wac *wacom, unsigned char *data, int last_touch_count)
 {
         struct wacom_features *features = &wacom->features;
         struct input_dev *input = wacom->input;
@@ -1664,7 +1669,7 @@ static void wacom_bpt3_touch_msg(struct wacom_wac *wacom, unsigned char *data)
         int slot = input_mt_get_slot_by_key(input, data[0]);
 
         if (slot < 0)
-                return;
+                return 0;
 
         touch = touch && !wacom->shared->stylus_in_proximity;
 
@@ -1696,7 +1701,9 @@ static void wacom_bpt3_touch_msg(struct wacom_wac *wacom, unsigned char *data)
                 input_report_abs(input, ABS_MT_POSITION_Y, y);
                 input_report_abs(input, ABS_MT_TOUCH_MAJOR, width);
                 input_report_abs(input, ABS_MT_TOUCH_MINOR, height);
+                last_touch_count++;
         }
+        return last_touch_count;
 }
 
 static void wacom_bpt3_button_msg(struct wacom_wac *wacom, unsigned char *data)
@@ -1721,6 +1728,7 @@ static int wacom_bpt3_touch(struct wacom_wac *wacom)
         unsigned char *data = wacom->data;
         int count = data[1] & 0x07;
         int i;
+        int contact_with_no_pen_down_count = 0;
 
         if (data[0] != 0x02)
             return 0;
@@ -1731,12 +1739,15 @@ static int wacom_bpt3_touch(struct wacom_wac *wacom)
                 int msg_id = data[offset];
 
                 if (msg_id >= 2 && msg_id <= 17)
-                        wacom_bpt3_touch_msg(wacom, data + offset);
+                        contact_with_no_pen_down_count = 
+                            wacom_bpt3_touch_msg(wacom, data + offset,
+                                                 contact_with_no_pen_down_count);
                 else if (msg_id == 128)
                         wacom_bpt3_button_msg(wacom, data + offset);
 
         }
         input_mt_report_pointer_emulation(input, true);
+        wacom->shared->touch_down = (contact_with_no_pen_down_count > 0);
 
         return 1;
 }