HID: asus: Add i2c touchpad support

Update the hid-asus module to add multitouch support for the Asus i2c touchpad.

This patch aims to resolve the issue raised here:
https://bugzilla.kernel.org/show_bug.cgi?id=120181

The issue is in relation to an Asus touchpad device which currently does not
have multitouch support.

The device currently falls through to the hid-generic driver which
treats the device as a mouse.

This patch aims to add the multitouch support.

[jkosina@suse.cz: move most of the 'patch comment' into actual changelog]
[jkosina@suse.cz: drop hunk that changes ->name of the driver]
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Brendan McGrath <redmcg@redmandi.dyndns.org>
Signed-off-by: Victor Vlasenko <victor.vlasenko@sysgears.com>
Signed-off-by: Frederik Wenigwieser <frederik.wenigwieser@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/Kconfig

@@ -138,7 +138,7 @@ config HID_ASUS
 	tristate "Asus"
 	depends on I2C_HID
 	---help---
-	Support for Asus notebook built-in keyboard via i2c.
+	Support for Asus notebook built-in keyboard and touchpad via i2c.
 
 	Supported devices:
 	- EeeBook X205TA

drivers/hid/hid-asus.c

@@ -11,6 +11,12 @@
  *  This module based on hid-ortek by
  *  Copyright (c) 2010 Johnathon Harris <jmharris@gmail.com>
  *  Copyright (c) 2011 Jiri Kosina
+ *
+ *  This module has been updated to add support for Asus i2c touchpad.
+ *
+ *  Copyright (c) 2016 Brendan McGrath <redmcg@redmandi.dyndns.org>
+ *  Copyright (c) 2016 Victor Vlasenko <victor.vlasenko@sysgears.com>
+ *  Copyright (c) 2016 Frederik Wenigwieser <frederik.wenigwieser@gmail.com>
  */
 
 /*
@@ -20,16 +26,287 @@
  * any later version.
  */
 
-#include <linux/device.h>
 #include <linux/hid.h>
 #include <linux/module.h>
+#include <linux/input/mt.h>
 
 #include "hid-ids.h"
 
+MODULE_AUTHOR("Yusuke Fujimaki <usk.fujimaki@gmail.com>");
+MODULE_AUTHOR("Brendan McGrath <redmcg@redmandi.dyndns.org>");
+MODULE_AUTHOR("Victor Vlasenko <victor.vlasenko@sysgears.com>");
+MODULE_AUTHOR("Frederik Wenigwieser <frederik.wenigwieser@gmail.com>");
+MODULE_DESCRIPTION("Asus HID Keyboard and TouchPad");
+
+#define FEATURE_REPORT_ID 0x0d
+#define INPUT_REPORT_ID 0x5d
+
+#define INPUT_REPORT_SIZE 28
+
+#define MAX_CONTACTS 5
+
+#define MAX_X 2794
+#define MAX_Y 1758
+#define MAX_TOUCH_MAJOR 8
+#define MAX_PRESSURE 128
+
+#define CONTACT_DATA_SIZE 5
+
+#define BTN_LEFT_MASK 0x01
+#define CONTACT_TOOL_TYPE_MASK 0x80
+#define CONTACT_X_MSB_MASK 0xf0
+#define CONTACT_Y_MSB_MASK 0x0f
+#define CONTACT_TOUCH_MAJOR_MASK 0x07
+#define CONTACT_PRESSURE_MASK 0x7f
+
+#define QUIRK_FIX_NOTEBOOK_REPORT	BIT(0)
+#define QUIRK_NO_INIT_REPORTS		BIT(1)
+#define QUIRK_SKIP_INPUT_MAPPING	BIT(2)
+#define QUIRK_IS_MULTITOUCH		BIT(3)
+
+#define NOTEBOOK_QUIRKS			QUIRK_FIX_NOTEBOOK_REPORT
+#define TOUCHPAD_QUIRKS			(QUIRK_NO_INIT_REPORTS | \
+						 QUIRK_SKIP_INPUT_MAPPING | \
+						 QUIRK_IS_MULTITOUCH)
+
+#define TRKID_SGN       ((TRKID_MAX + 1) >> 1)
+
+struct asus_drvdata {
+	unsigned long quirks;
+	struct input_dev *input;
+};
+
+static void asus_report_contact_down(struct input_dev *input,
+		int toolType, u8 *data)
+{
+	int touch_major, pressure;
+	int x = (data[0] & CONTACT_X_MSB_MASK) << 4 | data[1];
+	int y = MAX_Y - ((data[0] & CONTACT_Y_MSB_MASK) << 8 | data[2]);
+
+	if (toolType == MT_TOOL_PALM) {
+		touch_major = MAX_TOUCH_MAJOR;
+		pressure = MAX_PRESSURE;
+	} else {
+		touch_major = (data[3] >> 4) & CONTACT_TOUCH_MAJOR_MASK;
+		pressure = data[4] & CONTACT_PRESSURE_MASK;
+	}
+
+	input_report_abs(input, ABS_MT_POSITION_X, x);
+	input_report_abs(input, ABS_MT_POSITION_Y, y);
+	input_report_abs(input, ABS_MT_TOUCH_MAJOR, touch_major);
+	input_report_abs(input, ABS_MT_PRESSURE, pressure);
+}
+
+/* Required for Synaptics Palm Detection */
+static void asus_report_tool_width(struct input_dev *input)
+{
+	struct input_mt *mt = input->mt;
+	struct input_mt_slot *oldest;
+	int oldid, count, i;
+
+	oldest = NULL;
+	oldid = mt->trkid;
+	count = 0;
+
+	for (i = 0; i < mt->num_slots; ++i) {
+		struct input_mt_slot *ps = &mt->slots[i];
+		int id = input_mt_get_value(ps, ABS_MT_TRACKING_ID);
+
+		if (id < 0)
+			continue;
+		if ((id - oldid) & TRKID_SGN) {
+			oldest = ps;
+			oldid = id;
+		}
+		count++;
+	}
+
+	if (oldest) {
+		input_report_abs(input, ABS_TOOL_WIDTH,
+			input_mt_get_value(oldest, ABS_MT_TOUCH_MAJOR));
+	}
+}
+
+static void asus_report_input(struct input_dev *input, u8 *data)
+{
+	int i;
+	u8 *contactData = data + 2;
+
+	for (i = 0; i < MAX_CONTACTS; i++) {
+		bool down = !!(data[1] & BIT(i+3));
+		int toolType = contactData[3] & CONTACT_TOOL_TYPE_MASK ?
+						MT_TOOL_PALM : MT_TOOL_FINGER;
+
+		input_mt_slot(input, i);
+		input_mt_report_slot_state(input, toolType, down);
+
+		if (down) {
+			asus_report_contact_down(input, toolType, contactData);
+			contactData += CONTACT_DATA_SIZE;
+		}
+	}
+
+	input_report_key(input, BTN_LEFT, data[1] & BTN_LEFT_MASK);
+	asus_report_tool_width(input);
+
+	input_mt_sync_frame(input);
+	input_sync(input);
+}
+
+static int asus_raw_event(struct hid_device *hdev,
+		struct hid_report *report, u8 *data, int size)
+{
+	struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+
+	if (drvdata->quirks & QUIRK_IS_MULTITOUCH &&
+					 data[0] == INPUT_REPORT_ID &&
+						size == INPUT_REPORT_SIZE) {
+		asus_report_input(drvdata->input, data);
+		return 1;
+	}
+
+	return 0;
+}
+
+static int asus_input_configured(struct hid_device *hdev, struct hid_input *hi)
+{
+	struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+
+	if (drvdata->quirks & QUIRK_IS_MULTITOUCH) {
+		int ret;
+		struct input_dev *input = hi->input;
+
+		input_set_abs_params(input, ABS_MT_POSITION_X, 0, MAX_X, 0, 0);
+		input_set_abs_params(input, ABS_MT_POSITION_Y, 0, MAX_Y, 0, 0);
+		input_set_abs_params(input, ABS_TOOL_WIDTH, 0, MAX_TOUCH_MAJOR, 0, 0);
+		input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0, MAX_TOUCH_MAJOR, 0, 0);
+		input_set_abs_params(input, ABS_MT_PRESSURE, 0, MAX_PRESSURE, 0, 0);
+
+		__set_bit(BTN_LEFT, input->keybit);
+		__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
+
+		ret = input_mt_init_slots(input, MAX_CONTACTS, INPUT_MT_POINTER);
+
+		if (ret) {
+			hid_err(hdev, "Asus input mt init slots failed: %d\n", ret);
+			return ret;
+		}
+
+		drvdata->input = input;
+	}
+
+	return 0;
+}
+
+static int asus_input_mapping(struct hid_device *hdev,
+		struct hid_input *hi, struct hid_field *field,
+		struct hid_usage *usage, unsigned long **bit,
+		int *max)
+{
+	struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+
+	if (drvdata->quirks & QUIRK_SKIP_INPUT_MAPPING) {
+		/* Don't map anything from the HID report.
+		 * We do it all manually in asus_input_configured
+		 */
+		return -1;
+	}
+
+	return 0;
+}
+
+static int asus_start_multitouch(struct hid_device *hdev)
+{
+	int ret;
+	const unsigned char buf[] = { FEATURE_REPORT_ID, 0x00, 0x03, 0x01, 0x00 };
+	unsigned char *dmabuf = kmemdup(buf, sizeof(buf), GFP_KERNEL);
+
+	if (!dmabuf) {
+		ret = -ENOMEM;
+		hid_err(hdev, "Asus failed to alloc dma buf: %d\n", ret);
+		return ret;
+	}
+
+	ret = hid_hw_raw_request(hdev, dmabuf[0], dmabuf, sizeof(buf),
+					HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
+
+	kfree(dmabuf);
+
+	if (ret != sizeof(buf)) {
+		hid_err(hdev, "Asus failed to start multitouch: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int __maybe_unused asus_reset_resume(struct hid_device *hdev)
+{
+	struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+
+	if (drvdata->quirks & QUIRK_IS_MULTITOUCH)
+		return asus_start_multitouch(hdev);
+
+	return 0;
+}
+
+static int asus_probe(struct hid_device *hdev, const struct hid_device_id *id)
+{
+	int ret;
+	struct asus_drvdata *drvdata;
+
+	drvdata = devm_kzalloc(&hdev->dev, sizeof(*drvdata), GFP_KERNEL);
+	if (drvdata == NULL) {
+		hid_err(hdev, "Can't alloc Asus descriptor\n");
+		return -ENOMEM;
+	}
+
+	hid_set_drvdata(hdev, drvdata);
+
+	drvdata->quirks = id->driver_data;
+
+	if (drvdata->quirks & QUIRK_NO_INIT_REPORTS)
+		hdev->quirks |= HID_QUIRK_NO_INIT_REPORTS;
+
+	ret = hid_parse(hdev);
+	if (ret) {
+		hid_err(hdev, "Asus hid parse failed: %d\n", ret);
+		return ret;
+	}
+
+	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
+	if (ret) {
+		hid_err(hdev, "Asus hw start failed: %d\n", ret);
+		return ret;
+	}
+
+	if (!drvdata->input) {
+		hid_err(hdev, "Asus input not registered\n");
+		ret = -ENOMEM;
+		goto err_stop_hw;
+	}
+
+	drvdata->input->name = "Asus TouchPad";
+
+	if (drvdata->quirks & QUIRK_IS_MULTITOUCH) {
+		ret = asus_start_multitouch(hdev);
+		if (ret)
+			goto err_stop_hw;
+	}
+
+	return 0;
+err_stop_hw:
+	hid_hw_stop(hdev);
+	return ret;
+}
+
 static __u8 *asus_report_fixup(struct hid_device *hdev, __u8 *rdesc,
 		unsigned int *rsize)
 {
-	if (*rsize >= 56 && rdesc[54] == 0x25 && rdesc[55] == 0x65) {
+	struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+
+	if (drvdata->quirks & QUIRK_FIX_NOTEBOOK_REPORT &&
+			*rsize >= 56 && rdesc[54] == 0x25 && rdesc[55] == 0x65) {
 		hid_info(hdev, "Fixing up Asus notebook report descriptor\n");
 		rdesc[55] = 0xdd;
 	}
@@ -37,15 +314,25 @@ static __u8 *asus_report_fixup(struct hid_device *hdev, __u8 *rdesc,
 }
 
 static const struct hid_device_id asus_devices[] = {
-	{ HID_I2C_DEVICE(USB_VENDOR_ID_ASUSTEK, USB_DEVICE_ID_ASUSTEK_NOTEBOOK_KEYBOARD) },
+	{ HID_I2C_DEVICE(USB_VENDOR_ID_ASUSTEK,
+		 USB_DEVICE_ID_ASUSTEK_NOTEBOOK_KEYBOARD), NOTEBOOK_QUIRKS},
+	{ HID_I2C_DEVICE(USB_VENDOR_ID_ASUSTEK,
+			 USB_DEVICE_ID_ASUSTEK_TOUCHPAD), TOUCHPAD_QUIRKS },
 	{ }
 };
 MODULE_DEVICE_TABLE(hid, asus_devices);
 
 static struct hid_driver asus_driver = {
-	.name = "asus",
-	.id_table = asus_devices,
-	.report_fixup = asus_report_fixup
+	.name			= "asus",
+	.id_table		= asus_devices,
+	.report_fixup		= asus_report_fixup,
+	.probe                  = asus_probe,
+	.input_mapping          = asus_input_mapping,
+	.input_configured       = asus_input_configured,
+#ifdef CONFIG_PM
+	.reset_resume           = asus_reset_resume,
+#endif
+	.raw_event		= asus_raw_event
 };
 module_hid_driver(asus_driver);
 

drivers/hid/hid-core.c

@@ -1857,6 +1857,7 @@ static const struct hid_device_id hid_have_special_driver[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_FOUNTAIN_TP_ONLY) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_GEYSER1_TP_ONLY) },
 	{ HID_I2C_DEVICE(USB_VENDOR_ID_ASUSTEK, USB_DEVICE_ID_ASUSTEK_NOTEBOOK_KEYBOARD) },
+	{ HID_I2C_DEVICE(USB_VENDOR_ID_ASUSTEK, USB_DEVICE_ID_ASUSTEK_TOUCHPAD) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_AUREAL, USB_DEVICE_ID_AUREAL_W01RN) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_BELKIN, USB_DEVICE_ID_FLIP_KVM) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_BETOP_2185BFM, 0x2208) },

drivers/hid/hid-ids.h

@@ -171,6 +171,7 @@
 #define USB_DEVICE_ID_ASUSTEK_LCM	0x1726
 #define USB_DEVICE_ID_ASUSTEK_LCM2	0x175b
 #define USB_DEVICE_ID_ASUSTEK_NOTEBOOK_KEYBOARD	0x8585
+#define USB_DEVICE_ID_ASUSTEK_TOUCHPAD	0x0101
 
 #define USB_VENDOR_ID_ATEN		0x0557
 #define USB_DEVICE_ID_ATEN_UC100KM	0x2004