Input: wacom - retrieve maximum number of touch points

From the HID usage table when it is supported.

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>

3 files changed, 65 insertions, 24 deletions

diff --git a/drivers/input/tablet/wacom_sys.c b/drivers/input/tablet/wacom_sys.c
index 98e9dd692d68..be13223793fb 100644
--- a/drivers/input/tablet/wacom_sys.c
+++ b/drivers/input/tablet/wacom_sys.c
@@ -28,6 +28,7 @@
 #define HID_USAGE_Y_TILT		0x3e
 #define HID_USAGE_FINGER		0x22
 #define HID_USAGE_STYLUS		0x20
+#define HID_USAGE_CONTACTMAX		0x55
 #define HID_COLLECTION			0xa1
 #define HID_COLLECTION_LOGICAL		0x02
 #define HID_COLLECTION_END		0xc0
@@ -201,6 +202,27 @@ static int wacom_parse_logical_collection(unsigned char *report,
 	return length;
 }
 
+static void wacom_retrieve_report_data(struct usb_interface *intf,
+				       struct wacom_features *features)
+{
+	int result = 0;
+	unsigned char *rep_data;
+
+	rep_data = kmalloc(2, GFP_KERNEL);
+	if (rep_data) {
+
+		rep_data[0] = 12;
+		result = wacom_get_report(intf, WAC_HID_FEATURE_REPORT,
+					  rep_data[0], &rep_data, 2,
+					  WAC_MSG_RETRIES);
+
+		if (result >= 0 && rep_data[1] > 2)
+			features->touch_max = rep_data[1];
+
+		kfree(rep_data);
+	}
+}
+
 /*
  * Interface Descriptor of wacom devices can be incomplete and
  * inconsistent so wacom_features table is used to store stylus
@@ -377,6 +399,11 @@ static int wacom_parse_hid(struct usb_interface *intf,
 				pen = 1;
 				i++;
 				break;
+
+			case HID_USAGE_CONTACTMAX:
+				wacom_retrieve_report_data(intf, features);
+				i++;
+				break;
 			}
 			break;
 
@@ -1085,7 +1112,7 @@ static int wacom_probe(struct usb_interface *intf, const struct usb_device_id *i
 
 	endpoint = &intf->cur_altsetting->endpoint[0].desc;
 
-	/* Retrieve the physical and logical size for OEM devices */
+	/* Retrieve the physical and logical size for touch devices */
 	error = wacom_retrieve_hid_descriptor(intf, features);
 	if (error)
 		goto fail3;
diff --git a/drivers/input/tablet/wacom_wac.c b/drivers/input/tablet/wacom_wac.c
index d96e186f71dc..e5cd0e57d178 100644
--- a/drivers/input/tablet/wacom_wac.c
+++ b/drivers/input/tablet/wacom_wac.c
@@ -1434,7 +1434,7 @@ void wacom_setup_input_capabilities(struct input_dev *input_dev,
 			__set_bit(BTN_TOOL_TRIPLETAP, input_dev->keybit);
 			__set_bit(BTN_TOOL_QUADTAP, input_dev->keybit);
 
-			input_mt_init_slots(input_dev, 16);
+			input_mt_init_slots(input_dev, features->touch_max);
 
 			input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR,
 			                     0, 255, 0, 0);
@@ -1467,7 +1467,7 @@ void wacom_setup_input_capabilities(struct input_dev *input_dev,
 	case TABLETPC2FG:
 		if (features->device_type == BTN_TOOL_FINGER) {
 
-			input_mt_init_slots(input_dev, 2);
+			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);
 			input_set_abs_params(input_dev, ABS_MT_POSITION_X,
@@ -1522,6 +1522,7 @@ void wacom_setup_input_capabilities(struct input_dev *input_dev,
 
 			__set_bit(BTN_TOOL_FINGER, input_dev->keybit);
 			__set_bit(BTN_TOOL_DOUBLETAP, input_dev->keybit);
+			input_mt_init_slots(input_dev, features->touch_max);
 
 			if (features->pktlen == WACOM_PKGLEN_BBTOUCH3) {
 				__set_bit(BTN_TOOL_TRIPLETAP,
@@ -1529,13 +1530,9 @@ void wacom_setup_input_capabilities(struct input_dev *input_dev,
 				__set_bit(BTN_TOOL_QUADTAP,
 					  input_dev->keybit);
 
-				input_mt_init_slots(input_dev, 16);
-
 				input_set_abs_params(input_dev,
 						     ABS_MT_TOUCH_MAJOR,
 						     0, 255, 0, 0);
-			} else {
-				input_mt_init_slots(input_dev, 2);
 			}
 
 			input_set_abs_params(input_dev, ABS_MT_POSITION_X,
@@ -1724,13 +1721,16 @@ static const struct wacom_features wacom_features_0xBC =
 	  63, INTUOS4, WACOM_INTUOS3_RES, WACOM_INTUOS3_RES };
 static const struct wacom_features wacom_features_0x26 =
 	{ "Wacom Intuos5 touch S", WACOM_PKGLEN_INTUOS,  31496, 19685, 2047,
-	  63, INTUOS5S, WACOM_INTUOS3_RES, WACOM_INTUOS3_RES };
+	  63, INTUOS5S, WACOM_INTUOS3_RES, WACOM_INTUOS3_RES,
+	  .touch_max = 16 };
 static const struct wacom_features wacom_features_0x27 =
 	{ "Wacom Intuos5 touch M", WACOM_PKGLEN_INTUOS,  44704, 27940, 2047,
-	  63, INTUOS5, WACOM_INTUOS3_RES, WACOM_INTUOS3_RES };
+	  63, INTUOS5, WACOM_INTUOS3_RES, WACOM_INTUOS3_RES,
+	  .touch_max = 16 };
 static const struct wacom_features wacom_features_0x28 =
 	{ "Wacom Intuos5 touch L", WACOM_PKGLEN_INTUOS, 65024, 40640, 2047,
-	  63, INTUOS5L, WACOM_INTUOS3_RES, WACOM_INTUOS3_RES };
+	  63, INTUOS5L, WACOM_INTUOS3_RES, WACOM_INTUOS3_RES,
+	  .touch_max = 16 };
 static const struct wacom_features wacom_features_0x29 =
 	{ "Wacom Intuos5 S", WACOM_PKGLEN_INTUOS,  31496, 19685, 2047,
 	  63, INTUOS5S, WACOM_INTUOS3_RES, WACOM_INTUOS3_RES };
@@ -1778,13 +1778,16 @@ static const struct wacom_features wacom_features_0x9F =
 	  0, TABLETPC, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
 static const struct wacom_features wacom_features_0xE2 =
 	{ "Wacom ISDv4 E2",       WACOM_PKGLEN_TPC2FG,    26202, 16325,  255,
-	  0, TABLETPC2FG, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
+	  0, TABLETPC2FG, WACOM_INTUOS_RES, WACOM_INTUOS_RES,
+	  .touch_max = 2 };
 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 };
+	  0, TABLETPC2FG, WACOM_INTUOS_RES, WACOM_INTUOS_RES,
+	  .touch_max = 2 };
 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 };
+	  0, TABLETPC2FG, WACOM_INTUOS_RES, WACOM_INTUOS_RES,
+	.touch_max = 2 };
 static const struct wacom_features wacom_features_0xEC =
 	{ "Wacom ISDv4 EC",       WACOM_PKGLEN_GRAPHIRE,  25710, 14500,  255,
 	  0, TABLETPC,    WACOM_INTUOS_RES, WACOM_INTUOS_RES };
@@ -1793,19 +1796,22 @@ static const struct wacom_features wacom_features_0x47 =
 	  31, INTUOS, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
 static const struct wacom_features wacom_features_0x84 =
 	{ "Wacom Wireless Receiver", WACOM_PKGLEN_WIRELESS, 0, 0, 0,
-	  0, WIRELESS, 0, 0 };
+	  0, WIRELESS, 0, 0, .touch_max = 16 };
 static const struct wacom_features wacom_features_0xD0 =
 	{ "Wacom Bamboo 2FG",     WACOM_PKGLEN_BBFUN,     14720,  9200, 1023,
-	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
+	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES,
+	  .touch_max = 2 };
 static const struct wacom_features wacom_features_0xD1 =
 	{ "Wacom Bamboo 2FG 4x5", WACOM_PKGLEN_BBFUN,     14720,  9200, 1023,
-	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
+	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES,
+	  .touch_max = 2 };
 static const struct wacom_features wacom_features_0xD2 =
 	{ "Wacom Bamboo Craft",   WACOM_PKGLEN_BBFUN,     14720,  9200, 1023,
 	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
 static const struct wacom_features wacom_features_0xD3 =
 	{ "Wacom Bamboo 2FG 6x8", WACOM_PKGLEN_BBFUN,     21648, 13700, 1023,
-	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
+	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES,
+	  .touch_max = 2 };
 static const struct wacom_features wacom_features_0xD4 =
 	{ "Wacom Bamboo Pen",     WACOM_PKGLEN_BBFUN,     14720,  9200, 1023,
 	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
@@ -1814,28 +1820,35 @@ static const struct wacom_features wacom_features_0xD5 =
 	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
 static const struct wacom_features wacom_features_0xD6 =
 	{ "Wacom BambooPT 2FG 4x5", WACOM_PKGLEN_BBFUN,   14720,  9200, 1023,
-	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
+	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES,
+	  .touch_max = 2 };
 static const struct wacom_features wacom_features_0xD7 =
 	{ "Wacom BambooPT 2FG Small", WACOM_PKGLEN_BBFUN, 14720,  9200, 1023,
-	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
+	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES,
+	  .touch_max = 2 };
 static const struct wacom_features wacom_features_0xD8 =
 	{ "Wacom Bamboo Comic 2FG", WACOM_PKGLEN_BBFUN,   21648, 13700, 1023,
-	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
+	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES,
+	  .touch_max = 2 };
 static const struct wacom_features wacom_features_0xDA =
 	{ "Wacom Bamboo 2FG 4x5 SE", WACOM_PKGLEN_BBFUN,  14720,  9200, 1023,
-	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
+	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES,
+	  .touch_max = 2 };
 static struct wacom_features wacom_features_0xDB =
 	{ "Wacom Bamboo 2FG 6x8 SE", WACOM_PKGLEN_BBFUN,  21648, 13700, 1023,
-	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
+	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES,
+	  .touch_max = 2 };
 static const struct wacom_features wacom_features_0xDD =
         { "Wacom Bamboo Connect", WACOM_PKGLEN_BBPEN,     14720,  9200, 1023,
           31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
 static const struct wacom_features wacom_features_0xDE =
         { "Wacom Bamboo 16FG 4x5", WACOM_PKGLEN_BBPEN,    14720,  9200, 1023,
-          31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
+	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES,
+	  .touch_max = 16 };
 static const struct wacom_features wacom_features_0xDF =
         { "Wacom Bamboo 16FG 6x8", WACOM_PKGLEN_BBPEN,    21648, 13700, 1023,
-          31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
+	  31, BAMBOO_PT, WACOM_INTUOS_RES, WACOM_INTUOS_RES,
+	  .touch_max = 16 };
 static const struct wacom_features wacom_features_0x6004 =
 	{ "ISD-V4",               WACOM_PKGLEN_GRAPHIRE,  12800,  8000,  255,
 	  0, TABLETPC, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
diff --git a/drivers/input/tablet/wacom_wac.h b/drivers/input/tablet/wacom_wac.h
index 17ba1868f0cd..321269c1ac4c 100644
--- a/drivers/input/tablet/wacom_wac.h
+++ b/drivers/input/tablet/wacom_wac.h
@@ -99,6 +99,7 @@ struct wacom_features {
 	int pressure_fuzz;
 	int distance_fuzz;
 	unsigned quirks;
+	unsigned touch_max;
 };
 
 struct wacom_shared {