HID: multitouch: add haptic multitouch support

If CONFIG_HID_HAPTIC is enabled, and the device is recognized to have
simple haptic capabilities, try initializing the haptic device, check
input frames for pressure and handle it using hid_haptic_* API.

Signed-off-by: Angela Czubak <aczubak@google.com>
Co-developed-by: Jonathan Denose <jdenose@google.com>
Signed-off-by: Jonathan Denose <jdenose@google.com>
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>

Author: Angela Czubak

drivers/hid/hid-haptic.h

@@ -103,19 +103,25 @@ int hid_haptic_input_configured(struct hid_device *hdev,
 {
 	return 0;
 }
+static inline
+void hid_haptic_reset(struct hid_device *hdev, struct hid_haptic_device *haptic)
+{}
+static inline
 int hid_haptic_init(struct hid_device *hdev, struct hid_haptic_device **haptic_ptr)
 {
 	return 0;
 }
 static inline
-void hid_haptic_handle_press_release(struct hid_haptic_device *haptic)
-{}
+void hid_haptic_handle_press_release(struct hid_haptic_device *haptic) {}
 static inline
-void hid_haptic_pressure_reset(struct hid_haptic_device *haptic)
-{}
+bool hid_haptic_handle_input(struct hid_haptic_device *haptic)
+{
+	return false;
+}
+static inline
+void hid_haptic_pressure_reset(struct hid_haptic_device *haptic) {}
 static inline
 void hid_haptic_pressure_increase(struct hid_haptic_device *haptic,
 				  __s32 pressure)
 {}
 #endif
-

drivers/hid/hid-multitouch.c

@@ -49,6 +49,8 @@ MODULE_LICENSE("GPL");
 
 #include "hid-ids.h"
 
+#include "hid-haptic.h"
+
 /* quirks to control the device */
 #define MT_QUIRK_NOT_SEEN_MEANS_UP	BIT(0)
 #define MT_QUIRK_SLOT_IS_CONTACTID	BIT(1)
@@ -168,11 +170,13 @@ struct mt_report_data {
 struct mt_device {
 	struct mt_class mtclass;	/* our mt device class */
 	struct timer_list release_timer;	/* to release sticky fingers */
+	struct hid_haptic_device *haptic;	/* haptic related configuration */
 	struct hid_device *hdev;	/* hid_device we're attached to */
 	unsigned long mt_io_flags;	/* mt flags (MT_IO_FLAGS_*) */
 	__u8 inputmode_value;	/* InputMode HID feature value */
 	__u8 maxcontacts;
 	bool is_buttonpad;	/* is this device a button pad? */
+	bool is_haptic_touchpad;	/* is this device a haptic touchpad? */
 	bool serial_maybe;	/* need to check for serial protocol */
 
 	struct list_head applications;
@@ -533,6 +537,8 @@ static void mt_feature_mapping(struct hid_device *hdev,
 			mt_get_feature(hdev, field->report);
 		break;
 	}
+
+	hid_haptic_feature_mapping(hdev, td->haptic, field, usage);
 }
 
 static void set_abs(struct input_dev *input, unsigned int code,
@@ -888,6 +894,9 @@ static int mt_touch_input_mapping(struct hid_device *hdev, struct hid_input *hi,
 		case HID_DG_TIPPRESSURE:
 			set_abs(hi->input, ABS_MT_PRESSURE, field,
 				cls->sn_pressure);
+			td->is_haptic_touchpad =
+				hid_haptic_check_pressure_unit(td->haptic,
+							       hi, field);
 			MT_STORE_FIELD(p);
 			return 1;
 		case HID_DG_SCANTIME:
@@ -1008,6 +1017,8 @@ static void mt_sync_frame(struct mt_device *td, struct mt_application *app,
 
 	app->num_received = 0;
 	app->left_button_state = 0;
+	if (td->is_haptic_touchpad)
+		hid_haptic_pressure_reset(td->haptic);
 
 	if (test_bit(MT_IO_FLAGS_ACTIVE_SLOTS, &td->mt_io_flags))
 		set_bit(MT_IO_FLAGS_PENDING_SLOTS, &td->mt_io_flags);
@@ -1165,6 +1176,9 @@ static int mt_process_slot(struct mt_device *td, struct input_dev *input,
 			minor = minor >> 1;
 		}
 
+		if (td->is_haptic_touchpad)
+			hid_haptic_pressure_increase(td->haptic, *slot->p);
+
 		x = hdev->quirks & HID_QUIRK_X_INVERT ?
 			input_abs_get_max(input, ABS_MT_POSITION_X) - *slot->x :
 			*slot->x;
@@ -1366,6 +1380,9 @@ static int mt_touch_input_configured(struct hid_device *hdev,
 	if (cls->is_indirect)
 		app->mt_flags |= INPUT_MT_POINTER;
 
+	if (td->is_haptic_touchpad)
+		app->mt_flags |= INPUT_MT_TOTAL_FORCE;
+
 	if (app->quirks & MT_QUIRK_NOT_SEEN_MEANS_UP)
 		app->mt_flags |= INPUT_MT_DROP_UNUSED;
 
@@ -1401,6 +1418,7 @@ static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi,
 	struct mt_device *td = hid_get_drvdata(hdev);
 	struct mt_application *application;
 	struct mt_report_data *rdata;
+	int ret;
 
 	rdata = mt_find_report_data(td, field->report);
 	if (!rdata) {
@@ -1463,6 +1481,11 @@ static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi,
 	if (field->physical == HID_DG_STYLUS)
 		hi->application = HID_DG_STYLUS;
 
+	ret = hid_haptic_input_mapping(hdev, td->haptic, hi, field, usage, bit,
+				       max);
+	if (ret != 0)
+		return ret;
+
 	/* let hid-core decide for the others */
 	return 0;
 }
@@ -1685,6 +1708,14 @@ static int mt_input_configured(struct hid_device *hdev, struct hid_input *hi)
 	struct hid_report *report;
 	int ret;
 
+	if (td->is_haptic_touchpad && (td->mtclass.name == MT_CLS_WIN_8 ||
+	    td->mtclass.name == MT_CLS_WIN_8_FORCE_MULTI_INPUT)) {
+		if (hid_haptic_input_configured(hdev, td->haptic, hi) == 0)
+			td->is_haptic_touchpad = false;
+	} else {
+		td->is_haptic_touchpad = false;
+	}
+
 	list_for_each_entry(report, &hi->reports, hidinput_list) {
 		rdata = mt_find_report_data(td, report);
 		if (!rdata) {
@@ -1827,6 +1858,11 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
 		dev_err(&hdev->dev, "cannot allocate multitouch data\n");
 		return -ENOMEM;
 	}
+	td->haptic = devm_kzalloc(&hdev->dev, sizeof(*(td->haptic)), GFP_KERNEL);
+	if (!td->haptic)
+		return -ENOMEM;
+
+	td->haptic->hdev = hdev;
 	td->hdev = hdev;
 	td->mtclass = *mtclass;
 	td->inputmode_value = MT_INPUTMODE_TOUCHSCREEN;
@@ -1895,6 +1931,17 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
 
 	mt_set_modes(hdev, HID_LATENCY_NORMAL, TOUCHPAD_REPORT_ALL);
 
+	if (td->is_haptic_touchpad) {
+		if (hid_haptic_init(hdev, &td->haptic)) {
+			dev_warn(&hdev->dev, "Cannot allocate haptic for %s\n",
+				 hdev->name);
+			td->is_haptic_touchpad = false;
+			devm_kfree(&hdev->dev, td->haptic);
+		}
+	} else {
+		devm_kfree(&hdev->dev, td->haptic);
+	}
+
 	return 0;
 }