input: mouse: bcm5974: Add driver for Apple Magic Trackpad 2

Added support for Apple Magic Trackpad 2 in bcm5974 (MacBook Tochpad) driver.
The Magic Trackpad 2 needs to be switched into the finger-reporting-mode,
just like the other macbook touchpads as well. But the format is different to
the ones before. The Header is 12 Bytes long and each reported finger is
additional 9 Bytes. The data order is as well different.

The driver currently only supports USB. One option would be to integrate
bluetooth support into the bcm driver or to move the driver to the
hid-magicmouse which supports bluetooth. I integrated the driver into the bcm
and not the magicmouse driver, because this way i was able to compare the
outcome with the macbook touchpad as i dont own a magicmouse or a magictrackpad.

The patch has been tested by several people with a dkms:
https://github.com/robbi5/magictrackpad2-dkms
torvalds#332

Signed-off-by: Marek Wyborski <marek.wyborski@emwesoft.com>

drivers/hid/hid-apple.c

@@ -554,6 +554,8 @@ static const struct hid_device_id apple_devices[] = {
 		.driver_data = APPLE_HAS_FN | APPLE_ISO_KEYBOARD },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_WELLSPRING9_JIS),
 		.driver_data = APPLE_HAS_FN | APPLE_RDESC_JIS },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_MAGICTRACKPAD2),
+		.driver_data = APPLE_HAS_FN },
 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_ALU_WIRELESS_2009_ANSI),
 		.driver_data = APPLE_NUMLOCK_EMULATION | APPLE_HAS_FN },
 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_ALU_WIRELESS_2009_ISO),

drivers/hid/hid-core.c

@@ -1842,6 +1842,7 @@ static const struct hid_device_id hid_have_special_driver[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_WELLSPRING9_ANSI) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_WELLSPRING9_ISO) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_WELLSPRING9_JIS) },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_MAGICTRACKPAD2) },
 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_ALU_WIRELESS_2009_ANSI) },
 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_ALU_WIRELESS_2009_ISO) },
 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_ALU_WIRELESS_2009_JIS) },
@@ -2576,6 +2577,7 @@ static const struct hid_device_id hid_mouse_ignore_list[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_WELLSPRING9_ANSI) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_WELLSPRING9_ISO) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_WELLSPRING9_JIS) },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_MAGICTRACKPAD2) },
 	{ 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) },
 	{ }

drivers/hid/hid-ids.h

@@ -86,6 +86,7 @@
 #define USB_DEVICE_ID_APPLE_MIGHTYMOUSE	0x0304
 #define USB_DEVICE_ID_APPLE_MAGICMOUSE	0x030d
 #define USB_DEVICE_ID_APPLE_MAGICTRACKPAD	0x030e
+#define USB_DEVICE_ID_APPLE_MAGICTRACKPAD2	0x0265
 #define USB_DEVICE_ID_APPLE_FOUNTAIN_ANSI	0x020e
 #define USB_DEVICE_ID_APPLE_FOUNTAIN_ISO	0x020f
 #define USB_DEVICE_ID_APPLE_GEYSER_ANSI	0x0214

drivers/input/mouse/bcm5974.c

@@ -16,6 +16,7 @@
  * Copyright (C) 2005	   Peter Osterlund (petero2@telia.com)
  * Copyright (C) 2005	   Michael Hanselmann (linux-kernel@hansmi.ch)
  * Copyright (C) 2006	   Nicolas Boichat (nicolas@boichat.ch)
+ * Copyright (C) 2016	   Marek Wyborski (marek.wyborski@emwesoft.com)
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -96,6 +97,8 @@
 #define USB_DEVICE_ID_APPLE_WELLSPRING9_ANSI	0x0272
 #define USB_DEVICE_ID_APPLE_WELLSPRING9_ISO	0x0273
 #define USB_DEVICE_ID_APPLE_WELLSPRING9_JIS	0x0274
+/* MagicTrackpad2 (2015) */
+#define USB_DEVICE_ID_APPLE_MAGICTRACKPAD2	0x0265
 
 #define BCM5974_DEVICE(prod) {					\
 	.match_flags = (USB_DEVICE_ID_MATCH_DEVICE |		\
@@ -161,6 +164,8 @@ static const struct usb_device_id bcm5974_table[] = {
 	BCM5974_DEVICE(USB_DEVICE_ID_APPLE_WELLSPRING9_ANSI),
 	BCM5974_DEVICE(USB_DEVICE_ID_APPLE_WELLSPRING9_ISO),
 	BCM5974_DEVICE(USB_DEVICE_ID_APPLE_WELLSPRING9_JIS),
+	/* MagicTrackpad2 */
+	BCM5974_DEVICE(USB_DEVICE_ID_APPLE_MAGICTRACKPAD2),
 	/* Terminating entry */
 	{}
 };
@@ -190,20 +195,23 @@ enum tp_type {
 	TYPE1,			/* plain trackpad */
 	TYPE2,			/* button integrated in trackpad */
 	TYPE3,			/* additional header fields since June 2013 */
-	TYPE4			/* additional header field for pressure data */
+	TYPE4,			/* additional header field for pressure data */
+	TYPE5			/* format for magic trackpad 2 */
 };
 
 /* trackpad finger data offsets, le16-aligned */
 #define HEADER_TYPE1		(13 * sizeof(__le16))
 #define HEADER_TYPE2		(15 * sizeof(__le16))
 #define HEADER_TYPE3		(19 * sizeof(__le16))
 #define HEADER_TYPE4		(23 * sizeof(__le16))
+#define HEADER_TYPE5		( 6 * sizeof(__le16))
 
 /* trackpad button data offsets */
 #define BUTTON_TYPE1		0
 #define BUTTON_TYPE2		15
 #define BUTTON_TYPE3		23
 #define BUTTON_TYPE4		31
+#define BUTTON_TYPE5		1
 
 /* list of device capability bits */
 #define HAS_INTEGRATED_BUTTON	1
@@ -213,18 +221,21 @@ enum tp_type {
 #define FSIZE_TYPE2		(14 * sizeof(__le16))
 #define FSIZE_TYPE3		(14 * sizeof(__le16))
 #define FSIZE_TYPE4		(15 * sizeof(__le16))
+#define FSIZE_TYPE5		(9)
 
 /* offset from header to finger struct */
 #define DELTA_TYPE1		(0 * sizeof(__le16))
 #define DELTA_TYPE2		(0 * sizeof(__le16))
 #define DELTA_TYPE3		(0 * sizeof(__le16))
 #define DELTA_TYPE4		(1 * sizeof(__le16))
+#define DELTA_TYPE5		(0 * sizeof(__le16))
 
 /* usb control message mode switch data */
 #define USBMSG_TYPE1		8, 0x300, 0, 0, 0x1, 0x8
 #define USBMSG_TYPE2		8, 0x300, 0, 0, 0x1, 0x8
 #define USBMSG_TYPE3		8, 0x300, 0, 0, 0x1, 0x8
 #define USBMSG_TYPE4		2, 0x302, 2, 1, 0x1, 0x0
+#define USBMSG_TYPE5		2, 0x302, 1, 1, 0x1, 0x0
 
 /* Wellspring initialization constants */
 #define BCM5974_WELLSPRING_MODE_READ_REQUEST_ID		1
@@ -247,6 +258,18 @@ struct tp_finger {
 	__le16 multi;		/* one finger: varies, more fingers: constant */
 } __attribute__((packed,aligned(2)));
 
+/* trackpad finger structure for type5 (magic trackpad), le16-aligned */
+struct tp_finger_type5 {
+	u8 abs_x;		/* absolute x coodinate */
+	u8 abs_x_y;		/* absolute x,y coodinate */
+	u8 abs_y[2];		/* absolute y coodinate */
+	u8 touch_major;		/* touch area, major axis */
+	u8 touch_minor;		/* touch area, minor axis */
+	u8 size;		/* tool area, size */
+	u8 pressure;		/* pressure on forcetouch touchpad */
+	u8 orientation_origin;	/* orientation and id */
+} __attribute__((packed,aligned(2)));
+
 /* trackpad finger data size, empirically at least ten fingers */
 #define MAX_FINGERS		16
 #define MAX_FINGER_ORIENTATION	16384
@@ -497,6 +520,19 @@ static const struct bcm5974_config bcm5974_config_table[] = {
 		{ SN_COORD, -203, 6803 },
 		{ SN_ORIENT, -MAX_FINGER_ORIENTATION, MAX_FINGER_ORIENTATION }
 	},
+	{
+		USB_DEVICE_ID_APPLE_MAGICTRACKPAD2,
+		USB_DEVICE_ID_APPLE_MAGICTRACKPAD2,
+		USB_DEVICE_ID_APPLE_MAGICTRACKPAD2,
+		HAS_INTEGRATED_BUTTON,
+		0, sizeof(struct bt_data),
+		0x83, DATAFORMAT(TYPE5),
+		{ SN_PRESSURE, 0, 300 },
+		{ SN_WIDTH, 0, 2048 },
+		{ SN_COORD, -3678, 3934 },
+		{ SN_COORD, -2479, 2586 },
+		{ SN_ORIENT, -MAX_FINGER_ORIENTATION, MAX_FINGER_ORIENTATION }
+	},
 	{}
 };
 
@@ -539,9 +575,13 @@ static void setup_events_to_report(struct input_dev *input_dev,
 	/* finger touch area */
 	set_abs(input_dev, ABS_MT_TOUCH_MAJOR, &cfg->w);
 	set_abs(input_dev, ABS_MT_TOUCH_MINOR, &cfg->w);
+
 	/* finger approach area */
-	set_abs(input_dev, ABS_MT_WIDTH_MAJOR, &cfg->w);
-	set_abs(input_dev, ABS_MT_WIDTH_MINOR, &cfg->w);
+	if (cfg->tp_type != TYPE5) {
+		set_abs(input_dev, ABS_MT_WIDTH_MAJOR, &cfg->w);
+		set_abs(input_dev, ABS_MT_WIDTH_MINOR, &cfg->w);
+	}
+
 	/* finger orientation */
 	set_abs(input_dev, ABS_MT_ORIENTATION, &cfg->o);
 	/* finger position */
@@ -596,6 +636,23 @@ static void report_finger_data(struct input_dev *input, int slot,
 	input_report_abs(input, ABS_MT_POSITION_Y, pos->y);
 }
 
+static void report_finger_data_type5(struct input_dev *input, int slot,
+			       const struct input_mt_pos *pos,
+			       const struct tp_finger_type5 *f)
+{
+		input_mt_slot(input, slot);
+		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
+
+		input_report_abs(input, ABS_MT_TOUCH_MAJOR,
+				 raw2int(f->touch_major) << 2);
+		input_report_abs(input, ABS_MT_TOUCH_MINOR,
+				 raw2int(f->touch_minor) << 2);
+		input_report_abs(input, ABS_MT_ORIENTATION,
+			MAX_FINGER_ORIENTATION - ((f->orientation_origin & 0xf0) << 6));
+		input_report_abs(input, ABS_MT_POSITION_X, pos->x << 1);
+		input_report_abs(input, ABS_MT_POSITION_Y, pos->y << 1);
+}
+
 static void report_synaptics_data(struct input_dev *input,
 				  const struct bcm5974_config *cfg,
 				  const struct tp_finger *f, int raw_n)
@@ -615,11 +672,31 @@ static void report_synaptics_data(struct input_dev *input,
 	input_report_abs(input, ABS_TOOL_WIDTH, abs_w);
 }
 
+static void report_synaptics_data_type5(struct input_dev *input,
+				  const struct bcm5974_config *cfg,
+				  const struct tp_finger_type5 *f, int raw_n)
+{
+	int abs_p = 0, abs_w = 0;
+
+	if (raw_n) {
+		int p = f->pressure;
+		int w = f->size;
+		if (p && w) {
+			abs_p = p;
+			abs_w = w;
+		}
+	}
+
+	input_report_abs(input, ABS_PRESSURE, abs_p);
+	input_report_abs(input, ABS_TOOL_WIDTH, abs_w);
+}
+
 /* report trackpad data as logical trackpad state */
 static int report_tp_state(struct bcm5974 *dev, int size)
 {
 	const struct bcm5974_config *c = &dev->cfg;
 	const struct tp_finger *f;
+	const struct tp_finger_type5 *f_type5;
 	struct input_dev *input = dev->input;
 	int raw_n, i, n = 0;
 
@@ -629,23 +706,47 @@ static int report_tp_state(struct bcm5974 *dev, int size)
 	raw_n = (size - c->tp_header) / c->tp_fsize;
 
 	for (i = 0; i < raw_n; i++) {
+
 		f = get_tp_finger(dev, i);
-		if (raw2int(f->touch_major) == 0)
-			continue;
-		dev->pos[n].x = raw2int(f->abs_x);
-		dev->pos[n].y = c->y.min + c->y.max - raw2int(f->abs_y);
+
+		if (c->tp_type != TYPE5) {
+			if (raw2int(f->touch_major) == 0)
+				continue;
+			dev->pos[n].x = raw2int(f->abs_x);
+			dev->pos[n].y = c->y.min + c->y.max - raw2int(f->abs_y);
+		}
+		else {
+			u16 tmp_x;
+			u32 tmp_y;
+			f_type5 = (const struct tp_finger_type5*) f;
+			if (f_type5->pressure == 0)
+				continue;
+			tmp_x = le16_to_cpu(*((__le16*)f_type5)) & 0x1fff;
+			dev->pos[n].x = (s16) (tmp_x << 3) >> 3;
+			tmp_y = (s32) le32_to_cpu(*((__le32*)f_type5));
+			dev->pos[n].y = -(s32) (tmp_y << 6) >> 19;
+		}
 		dev->index[n++] = f;
 	}
 
 	input_mt_assign_slots(input, dev->slots, dev->pos, n, 0);
 
-	for (i = 0; i < n; i++)
-		report_finger_data(input, dev->slots[i],
-				   &dev->pos[i], dev->index[i]);
+	for (i = 0; i < n; i++) {
+		if (c->tp_type != TYPE5)
+			report_finger_data(input, dev->slots[i],
+					   &dev->pos[i], dev->index[i]);
+		else
+			report_finger_data_type5(input, dev->slots[i], &dev->pos[i],
+					(const struct tp_finger_type5 *) dev->index[i]);
+	}
 
 	input_mt_sync_frame(input);
 
-	report_synaptics_data(input, c, get_tp_finger(dev, 0), raw_n);
+	if (c->tp_type != TYPE5)
+		report_synaptics_data(input, c, get_tp_finger(dev, 0), raw_n);
+	else
+		report_synaptics_data_type5(input, c,
+			(const struct tp_finger_type5*) get_tp_finger(dev, 0), raw_n);
 
 	/* later types report button events via integrated button only */
 	if (c->caps & HAS_INTEGRATED_BUTTON) {