[PATCH v2 0/4] HID: wiiu-drc: Add a driver for the Wii U gamepad

[PATCH v2 0/4] HID: wiiu-drc: Add a driver for the Wii U gamepad

[Emmanuel Gil Peyrot]

This driver is for the DRC (wireless gamepad) when plugged to the DRH of
the Wii U, a chip exposing it as a USB device.

I tried to use this driver on master over usbip on my laptop, but usbip
disconnects the device right after the driver created the
/dev/input/event* files, so instead I have only tested this driver on
the 4.19 branch of the linux-wiiu[1] downstream.

Other than that, pretty much all of the HID parts of the gamepad work,
it’s only missing microphone, camera and NFC input now but those are
mostly standard (read require quirks) and pertain to other subsystems,
so I felt like this can be upstreamed already.

[1] https://gitlab.com/linux-wiiu/linux-wiiu

Changes since v1:
- Rename interfaces to be less redundant.
- Add comments for potentially unclear things.
- Reword some commits to include more needed information.
- Include all needed includes.
- Use helpful helper functions instead of (badly) reimplementing them
  myself.
- Always return the correct type for each function, to avoid some
  bool/int confusion, or returning 0 to mean error.
- Use myself as the module author, even though Ash did most of the
  initial work, I’m the one who will be maintaining this module from now
  on.
- Use input_set_capability() instead of set_bit(…, keybit) to also set
  BIT(EV_KEY) on evbit[0].
- Call hid_hw_start() before input_register_device() but after the setup
  functions, so that hid_hw_open() is never called before it.
- Add missing spin_lock_init() for the battery lock.
- Use a static atomic for the drc_num, and remove the comment about
  using the interface number.
- Interpret battery report as the voltage coming from an ADC, instead of
  the completely wrong ENERGY_NOW it was before.

So basically addressing Jonathan’s and Barnabás’ comments. :)

Ash Logan (1):
  HID: wiiu-drc: Add a driver for this gamepad

Emmanuel Gil Peyrot (3):
  HID: wiiu-drc: Implement touch reports
  HID: wiiu-drc: Add accelerometer, gyroscope and magnetometer readings
  HID: wiiu-drc: Add battery reporting

 drivers/hid/Kconfig        |   7 +
 drivers/hid/Makefile       |   1 +
 drivers/hid/hid-ids.h      |   1 +
 drivers/hid/hid-quirks.c   |   3 +
 drivers/hid/hid-wiiu-drc.c | 551 +++++++++++++++++++++++++++++++++++++
 5 files changed, 563 insertions(+)
 create mode 100644 drivers/hid/hid-wiiu-drc.c

-- 
2.31.1

[PATCH v2 1/4] HID: wiiu-drc: Add a driver for this gamepad

[Emmanuel Gil Peyrot]

From: Ash Logan <ash@heyquark.com>

This driver is for the DRC (gamepad) of the Wii U when wirelessly
connected to the DRH of the console, an internal chip exposing it as a
USB device.

This first patch exposes the buttons and sticks of this device, so that
it can act as a plain game controller.

The report format has been described by the libdrc folks at:
https://libdrc.org/docs/re/sc-input.html

Signed-off-by: Ash Logan <ash@heyquark.com>
Signed-off-by: Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
---
 drivers/hid/Kconfig        |   7 +
 drivers/hid/Makefile       |   1 +
 drivers/hid/hid-ids.h      |   1 +
 drivers/hid/hid-quirks.c   |   3 +
 drivers/hid/hid-wiiu-drc.c | 281 +++++++++++++++++++++++++++++++++++++
 5 files changed, 293 insertions(+)
 create mode 100644 drivers/hid/hid-wiiu-drc.c

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 4bf263c2d61a..7681d4614c0a 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -1105,6 +1105,13 @@ config HID_WACOM
 	  To compile this driver as a module, choose M here: the
 	  module will be called wacom.
 
+config HID_WIIU_DRC
+	tristate "Nintendo Wii U gamepad (DRC) over internal DRH"
+	depends on HID
+	help
+	  Support for the Wii U gamepad, when connected with the Wii U’s
+	  internal DRH chip.
+
 config HID_WIIMOTE
 	tristate "Nintendo Wii / Wii U peripherals"
 	depends on HID
diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
index 193431ec4db8..8fcaaeae4d65 100644
--- a/drivers/hid/Makefile
+++ b/drivers/hid/Makefile
@@ -134,6 +134,7 @@ wacom-objs			:= wacom_wac.o wacom_sys.o
 obj-$(CONFIG_HID_WACOM)		+= wacom.o
 obj-$(CONFIG_HID_WALTOP)	+= hid-waltop.o
 obj-$(CONFIG_HID_WIIMOTE)	+= hid-wiimote.o
+obj-$(CONFIG_HID_WIIU_DRC)	+= hid-wiiu-drc.o
 obj-$(CONFIG_HID_SENSOR_HUB)	+= hid-sensor-hub.o
 obj-$(CONFIG_HID_SENSOR_CUSTOM_SENSOR)	+= hid-sensor-custom.o
 
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 84b8da3e7d09..fbac0dd021f1 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -916,6 +916,7 @@
 #define USB_VENDOR_ID_NINTENDO		0x057e
 #define USB_DEVICE_ID_NINTENDO_WIIMOTE	0x0306
 #define USB_DEVICE_ID_NINTENDO_WIIMOTE2	0x0330
+#define USB_DEVICE_ID_NINTENDO_WIIU_DRH	0x0341
 
 #define USB_VENDOR_ID_NOVATEK		0x0603
 #define USB_DEVICE_ID_NOVATEK_PCT	0x0600
diff --git a/drivers/hid/hid-quirks.c b/drivers/hid/hid-quirks.c
index 3dd6f15f2a67..af400177537e 100644
--- a/drivers/hid/hid-quirks.c
+++ b/drivers/hid/hid-quirks.c
@@ -513,6 +513,9 @@ static const struct hid_device_id hid_have_special_driver[] = {
 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_NINTENDO, USB_DEVICE_ID_NINTENDO_WIIMOTE) },
 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_NINTENDO, USB_DEVICE_ID_NINTENDO_WIIMOTE2) },
 #endif
+#if IS_ENABLED(CONFIG_HID_WIIU_DRC)
+	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_NINTENDO, USB_DEVICE_ID_NINTENDO_WIIU_DRH) },
+#endif
 #if IS_ENABLED(CONFIG_HID_NTI)
 	{ HID_USB_DEVICE(USB_VENDOR_ID_NTI, USB_DEVICE_ID_USB_SUN) },
 #endif
diff --git a/drivers/hid/hid-wiiu-drc.c b/drivers/hid/hid-wiiu-drc.c
new file mode 100644
index 000000000000..875ccfab7bbf
--- /dev/null
+++ b/drivers/hid/hid-wiiu-drc.c
@@ -0,0 +1,281 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * HID driver for Nintendo Wii U gamepad (DRC), connected via console-internal DRH
+ *
+ * Copyright (C) 2021 Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
+ * Copyright (C) 2019 Ash Logan <ash@heyquark.com>
+ * Copyright (C) 2013 Mema Hacking
+ *
+ * Based on the excellent work at http://libdrc.org/docs/re/sc-input.html and
+ * https://bitbucket.org/memahaxx/libdrc/src/master/src/input-receiver.cpp .
+ * libdrc code is licensed under BSD 2-Clause.
+ * Driver based on hid-udraw-ps3.c.
+ */
+
+#include <linux/device.h>
+#include <linux/hid.h>
+#include <linux/input.h>
+#include <linux/minmax.h>
+#include <linux/module.h>
+#include "hid-ids.h"
+
+#define DEVICE_NAME	"Nintendo Wii U gamepad (DRC)"
+
+/* Button and stick constants */
+#define VOLUME_MIN	0
+#define VOLUME_MAX	255
+#define NUM_STICK_AXES	4
+#define STICK_MIN	900
+#define STICK_MAX	3200
+
+#define BUTTON_SYNC	BIT(0)
+#define BUTTON_HOME	BIT(1)
+#define BUTTON_MINUS	BIT(2)
+#define BUTTON_PLUS	BIT(3)
+#define BUTTON_R	BIT(4)
+#define BUTTON_L	BIT(5)
+#define BUTTON_ZR	BIT(6)
+#define BUTTON_ZL	BIT(7)
+#define BUTTON_DOWN	BIT(8)
+#define BUTTON_UP	BIT(9)
+#define BUTTON_RIGHT	BIT(10)
+#define BUTTON_LEFT	BIT(11)
+#define BUTTON_Y	BIT(12)
+#define BUTTON_X	BIT(13)
+#define BUTTON_B	BIT(14)
+#define BUTTON_A	BIT(15)
+
+#define BUTTON_TV	BIT(21)
+#define BUTTON_R3	BIT(22)
+#define BUTTON_L3	BIT(23)
+
+#define BUTTON_POWER	BIT(25)
+
+/*
+ * The device is setup with multiple input devices:
+ * - A joypad with the buttons and sticks.
+ */
+
+struct drc {
+	struct input_dev *joy_input_dev;
+	struct hid_device *hdev;
+};
+
+/*
+ * The format of this report has been reversed by the libdrc project, the
+ * documentation can be found here:
+ * https://libdrc.org/docs/re/sc-input.html
+ *
+ * We receive this report from USB, but it is actually formed on the DRC, the
+ * DRH only retransmits it over USB.
+ */
+static int drc_raw_event(struct hid_device *hdev, struct hid_report *report,
+			 u8 *data, int len)
+{
+	struct drc *drc = hid_get_drvdata(hdev);
+	int i;
+	u32 buttons;
+
+	if (len != 128)
+		return -EINVAL;
+
+	buttons = (data[4] << 24) | (data[80] << 16) | (data[2] << 8) | data[3];
+	/* joypad */
+	input_report_key(drc->joy_input_dev, BTN_DPAD_RIGHT, buttons & BUTTON_RIGHT);
+	input_report_key(drc->joy_input_dev, BTN_DPAD_DOWN, buttons & BUTTON_DOWN);
+	input_report_key(drc->joy_input_dev, BTN_DPAD_LEFT, buttons & BUTTON_LEFT);
+	input_report_key(drc->joy_input_dev, BTN_DPAD_UP, buttons & BUTTON_UP);
+
+	input_report_key(drc->joy_input_dev, BTN_EAST, buttons & BUTTON_A);
+	input_report_key(drc->joy_input_dev, BTN_SOUTH, buttons & BUTTON_B);
+	input_report_key(drc->joy_input_dev, BTN_NORTH, buttons & BUTTON_X);
+	input_report_key(drc->joy_input_dev, BTN_WEST, buttons & BUTTON_Y);
+
+	input_report_key(drc->joy_input_dev, BTN_TL, buttons & BUTTON_L);
+	input_report_key(drc->joy_input_dev, BTN_TL2, buttons & BUTTON_ZL);
+	input_report_key(drc->joy_input_dev, BTN_TR, buttons & BUTTON_R);
+	input_report_key(drc->joy_input_dev, BTN_TR2, buttons & BUTTON_ZR);
+
+	input_report_key(drc->joy_input_dev, BTN_Z, buttons & BUTTON_TV);
+	input_report_key(drc->joy_input_dev, BTN_THUMBL, buttons & BUTTON_L3);
+	input_report_key(drc->joy_input_dev, BTN_THUMBR, buttons & BUTTON_R3);
+
+	input_report_key(drc->joy_input_dev, BTN_SELECT, buttons & BUTTON_MINUS);
+	input_report_key(drc->joy_input_dev, BTN_START, buttons & BUTTON_PLUS);
+	input_report_key(drc->joy_input_dev, BTN_MODE, buttons & BUTTON_HOME);
+
+	input_report_key(drc->joy_input_dev, BTN_DEAD, buttons & BUTTON_POWER);
+
+	for (i = 0; i < NUM_STICK_AXES; i++) {
+		s16 val = (data[7 + 2*i] << 8) | data[6 + 2*i];
+
+		val = clamp(val, STICK_MIN, STICK_MAX);
+
+		switch (i) {
+		case 0:
+			input_report_abs(drc->joy_input_dev, ABS_X, val);
+			break;
+		case 1:
+			input_report_abs(drc->joy_input_dev, ABS_Y, val);
+			break;
+		case 2:
+			input_report_abs(drc->joy_input_dev, ABS_RX, val);
+			break;
+		case 3:
+			input_report_abs(drc->joy_input_dev, ABS_RY, val);
+			break;
+		default:
+			break;
+		}
+	}
+
+	input_report_abs(drc->joy_input_dev, ABS_VOLUME, data[14]);
+	input_sync(drc->joy_input_dev);
+
+	/* let hidraw and hiddev handle the report */
+	return 0;
+}
+
+static int drc_open(struct input_dev *dev)
+{
+	struct drc *drc = input_get_drvdata(dev);
+
+	return hid_hw_open(drc->hdev);
+}
+
+static void drc_close(struct input_dev *dev)
+{
+	struct drc *drc = input_get_drvdata(dev);
+
+	hid_hw_close(drc->hdev);
+}
+
+static struct input_dev *allocate_and_setup(struct hid_device *hdev,
+					    const char *name)
+{
+	struct input_dev *input_dev;
+
+	input_dev = devm_input_allocate_device(&hdev->dev);
+	if (!input_dev)
+		return NULL;
+
+	input_dev->name = name;
+	input_dev->phys = hdev->phys;
+	input_dev->dev.parent = &hdev->dev;
+	input_dev->open = drc_open;
+	input_dev->close = drc_close;
+	input_dev->uniq = hdev->uniq;
+	input_dev->id.bustype = hdev->bus;
+	input_dev->id.vendor  = hdev->vendor;
+	input_dev->id.product = hdev->product;
+	input_dev->id.version = hdev->version;
+	input_set_drvdata(input_dev, hid_get_drvdata(hdev));
+
+	return input_dev;
+}
+
+static bool drc_setup_joypad(struct drc *drc,
+			     struct hid_device *hdev)
+{
+	struct input_dev *input_dev;
+
+	input_dev = allocate_and_setup(hdev, DEVICE_NAME " buttons and sticks");
+	if (!input_dev)
+		return false;
+
+	drc->joy_input_dev = input_dev;
+
+	input_set_capability(input_dev, EV_KEY, BTN_DPAD_RIGHT);
+	input_set_capability(input_dev, EV_KEY, BTN_DPAD_DOWN);
+	input_set_capability(input_dev, EV_KEY, BTN_DPAD_LEFT);
+	input_set_capability(input_dev, EV_KEY, BTN_DPAD_UP);
+	input_set_capability(input_dev, EV_KEY, BTN_EAST);
+	input_set_capability(input_dev, EV_KEY, BTN_SOUTH);
+	input_set_capability(input_dev, EV_KEY, BTN_NORTH);
+	input_set_capability(input_dev, EV_KEY, BTN_WEST);
+	input_set_capability(input_dev, EV_KEY, BTN_TL);
+	input_set_capability(input_dev, EV_KEY, BTN_TL2);
+	input_set_capability(input_dev, EV_KEY, BTN_TR);
+	input_set_capability(input_dev, EV_KEY, BTN_TR2);
+	input_set_capability(input_dev, EV_KEY, BTN_THUMBL);
+	input_set_capability(input_dev, EV_KEY, BTN_THUMBR);
+	input_set_capability(input_dev, EV_KEY, BTN_SELECT);
+	input_set_capability(input_dev, EV_KEY, BTN_START);
+	input_set_capability(input_dev, EV_KEY, BTN_MODE);
+
+	/*
+	 * These two buttons are actually TV Control and Power.
+	 *
+	 * TV Control draws a line at the bottom of the DRC’s screen saying to
+	 * go into System Settings (on the original proprietary OS), while
+	 * Power will shutdown the DRC when held for four seconds, but those
+	 * two are still normal buttons otherwise.
+	 */
+	input_set_capability(input_dev, EV_KEY, BTN_Z);
+	input_set_capability(input_dev, EV_KEY, BTN_DEAD);
+
+	input_set_abs_params(input_dev, ABS_X, STICK_MIN, STICK_MAX, 0, 0);
+	input_set_abs_params(input_dev, ABS_Y, STICK_MIN, STICK_MAX, 0, 0);
+	input_set_abs_params(input_dev, ABS_RX, STICK_MIN, STICK_MAX, 0, 0);
+	input_set_abs_params(input_dev, ABS_RY, STICK_MIN, STICK_MAX, 0, 0);
+	input_set_abs_params(input_dev, ABS_VOLUME, VOLUME_MIN, VOLUME_MAX, 0, 0);
+
+	return true;
+}
+
+static int drc_probe(struct hid_device *hdev, const struct hid_device_id *id)
+{
+	struct drc *drc;
+	int ret;
+
+	drc = devm_kzalloc(&hdev->dev, sizeof(struct drc), GFP_KERNEL);
+	if (!drc)
+		return -ENOMEM;
+
+	drc->hdev = hdev;
+
+	hid_set_drvdata(hdev, drc);
+
+	ret = hid_parse(hdev);
+	if (ret) {
+		hid_err(hdev, "parse failed\n");
+		return ret;
+	}
+
+	if (!drc_setup_joypad(drc, hdev)) {
+		hid_err(hdev, "could not allocate interface\n");
+		return -ENOMEM;
+	}
+
+	ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW | HID_CONNECT_DRIVER);
+	if (ret) {
+		hid_err(hdev, "hw start failed\n");
+		return ret;
+	}
+
+	ret = input_register_device(drc->joy_input_dev);
+	if (ret) {
+		hid_err(hdev, "failed to register interface\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct hid_device_id drc_devices[] = {
+	{ HID_USB_DEVICE(USB_VENDOR_ID_NINTENDO, USB_DEVICE_ID_NINTENDO_WIIU_DRH) },
+	{ }
+};
+MODULE_DEVICE_TABLE(hid, drc_devices);
+
+static struct hid_driver drc_driver = {
+	.name = "hid-wiiu-drc",
+	.id_table = drc_devices,
+	.raw_event = drc_raw_event,
+	.probe = drc_probe,
+};
+module_hid_driver(drc_driver);
+
+MODULE_AUTHOR("Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>");
+MODULE_DESCRIPTION("Nintendo Wii U gamepad (DRC) driver");
+MODULE_LICENSE("GPL");
-- 
2.31.1

[PATCH v2 2/4] HID: wiiu-drc: Implement touch reports

[Emmanuel Gil Peyrot]

There is an inaccessible border on each side, 100 units on the left and
right sides, and 200 units at the top and bottom.  The Y axis is
inverted too, these are the two main quirks of this touch panel.

I’ve been testing with weston-simple-touch mostly, but it also with the
rest of Weston and it aligns perfectly without the need of any
additional calibration.

Signed-off-by: Ash Logan <ash@heyquark.com>
Signed-off-by: Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
---
 drivers/hid/hid-wiiu-drc.c | 86 +++++++++++++++++++++++++++++++++++---
 1 file changed, 81 insertions(+), 5 deletions(-)

diff --git a/drivers/hid/hid-wiiu-drc.c b/drivers/hid/hid-wiiu-drc.c
index 875ccfab7bbf..33c02d3494aa 100644
--- a/drivers/hid/hid-wiiu-drc.c
+++ b/drivers/hid/hid-wiiu-drc.c
@@ -51,13 +51,27 @@
 
 #define BUTTON_POWER	BIT(25)
 
+/* Touch constants */
+/* Resolution in pixels */
+#define RES_X		854
+#define RES_Y		480
+/* Display/touch size in mm */
+#define WIDTH		138
+#define HEIGHT		79
+#define NUM_TOUCH_POINTS 10
+#define MAX_TOUCH_RES	(1 << 12)
+#define TOUCH_BORDER_X	100
+#define TOUCH_BORDER_Y	200
+
 /*
  * The device is setup with multiple input devices:
  * - A joypad with the buttons and sticks.
+ * - The touch area which works as a touchscreen.
  */
 
 struct drc {
 	struct input_dev *joy_input_dev;
+	struct input_dev *touch_input_dev;
 	struct hid_device *hdev;
 };
 
@@ -73,7 +87,7 @@ static int drc_raw_event(struct hid_device *hdev, struct hid_report *report,
 			 u8 *data, int len)
 {
 	struct drc *drc = hid_get_drvdata(hdev);
-	int i;
+	int i, x, y, pressure, base;
 	u32 buttons;
 
 	if (len != 128)
@@ -132,6 +146,42 @@ static int drc_raw_event(struct hid_device *hdev, struct hid_report *report,
 	input_report_abs(drc->joy_input_dev, ABS_VOLUME, data[14]);
 	input_sync(drc->joy_input_dev);
 
+	/* touch */
+	/*
+	 * Average touch points for improved accuracy.  Sadly these are always
+	 * reported extremely close from each other…  Even when the user
+	 * pressed two (or more) different points, all ten values will be
+	 * approximately in the middle of the pressure points.
+	 */
+	x = y = 0;
+	for (i = 0; i < NUM_TOUCH_POINTS; i++) {
+		base = 36 + 4 * i;
+
+		x += ((data[base + 1] & 0xF) << 8) | data[base];
+		y += ((data[base + 3] & 0xF) << 8) | data[base + 2];
+	}
+	x /= NUM_TOUCH_POINTS;
+	y /= NUM_TOUCH_POINTS;
+
+	/* Pressure reporting isn’t properly understood, so we don’t report it yet. */
+	pressure = 0;
+	pressure |= ((data[37] >> 4) & 7) << 0;
+	pressure |= ((data[39] >> 4) & 7) << 3;
+	pressure |= ((data[41] >> 4) & 7) << 6;
+	pressure |= ((data[43] >> 4) & 7) << 9;
+
+	if (pressure != 0) {
+		input_report_key(drc->touch_input_dev, BTN_TOUCH, 1);
+		input_report_key(drc->touch_input_dev, BTN_TOOL_FINGER, 1);
+
+		input_report_abs(drc->touch_input_dev, ABS_X, x);
+		input_report_abs(drc->touch_input_dev, ABS_Y, MAX_TOUCH_RES - y);
+	} else {
+		input_report_key(drc->touch_input_dev, BTN_TOUCH, 0);
+		input_report_key(drc->touch_input_dev, BTN_TOOL_FINGER, 0);
+	}
+	input_sync(drc->touch_input_dev);
+
 	/* let hidraw and hiddev handle the report */
 	return 0;
 }
@@ -223,6 +273,30 @@ static bool drc_setup_joypad(struct drc *drc,
 	return true;
 }
 
+static bool drc_setup_touch(struct drc *drc,
+			    struct hid_device *hdev)
+{
+	struct input_dev *input_dev;
+
+	input_dev = allocate_and_setup(hdev, DEVICE_NAME " touchscreen");
+	if (!input_dev)
+		return false;
+
+	drc->touch_input_dev = input_dev;
+
+	set_bit(INPUT_PROP_DIRECT, input_dev->propbit);
+
+	input_set_abs_params(input_dev, ABS_X, TOUCH_BORDER_X, MAX_TOUCH_RES - TOUCH_BORDER_X, 20, 0);
+	input_abs_set_res(input_dev, ABS_X, RES_X / WIDTH);
+	input_set_abs_params(input_dev, ABS_Y, TOUCH_BORDER_Y, MAX_TOUCH_RES - TOUCH_BORDER_Y, 20, 0);
+	input_abs_set_res(input_dev, ABS_Y, RES_Y / HEIGHT);
+
+	input_set_capability(input_dev, EV_KEY, BTN_TOUCH);
+	input_set_capability(input_dev, EV_KEY, BTN_TOOL_FINGER);
+
+	return true;
+}
+
 static int drc_probe(struct hid_device *hdev, const struct hid_device_id *id)
 {
 	struct drc *drc;
@@ -242,8 +316,9 @@ static int drc_probe(struct hid_device *hdev, const struct hid_device_id *id)
 		return ret;
 	}
 
-	if (!drc_setup_joypad(drc, hdev)) {
-		hid_err(hdev, "could not allocate interface\n");
+	if (!drc_setup_joypad(drc, hdev) ||
+	    !drc_setup_touch(drc, hdev)) {
+		hid_err(hdev, "could not allocate interfaces\n");
 		return -ENOMEM;
 	}
 
@@ -253,9 +328,10 @@ static int drc_probe(struct hid_device *hdev, const struct hid_device_id *id)
 		return ret;
 	}
 
-	ret = input_register_device(drc->joy_input_dev);
+	ret = input_register_device(drc->joy_input_dev) ||
+	      input_register_device(drc->touch_input_dev);
 	if (ret) {
-		hid_err(hdev, "failed to register interface\n");
+		hid_err(hdev, "failed to register interfaces\n");
 		return ret;
 	}
 
-- 
2.31.1

[PATCH v2 3/4] HID: wiiu-drc: Add accelerometer, gyroscope and magnetometer readings

[Emmanuel Gil Peyrot]

These are mostly untested so far, because I have no idea which userland
to test against, but evtest at least seems to give sensible values.

The magnetometer doesn’t have dedicated INPUT_PROP_ACCELEROMETER
buttons, so I used three clearly invalid absolute values, in the hope
that someone will fix that eventually.  Another solution might be to go
for the iio subsystem instead, but then it wouldn’t be tied to the HID
any longer and I would feel uneasy about that.  Especially because
multiple such gamepads could be connected to a single computer.

Signed-off-by: Ash Logan <ash@heyquark.com>
Signed-off-by: Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
---
 drivers/hid/hid-wiiu-drc.c | 77 ++++++++++++++++++++++++++++++++++++--
 1 file changed, 74 insertions(+), 3 deletions(-)

diff --git a/drivers/hid/hid-wiiu-drc.c b/drivers/hid/hid-wiiu-drc.c
index 33c02d3494aa..a631d405119e 100644
--- a/drivers/hid/hid-wiiu-drc.c
+++ b/drivers/hid/hid-wiiu-drc.c
@@ -63,15 +63,25 @@
 #define TOUCH_BORDER_X	100
 #define TOUCH_BORDER_Y	200
 
+/* Accelerometer, gyroscope and magnetometer constants */
+#define ACCEL_MIN	-(1 << 15)
+#define ACCEL_MAX	((1 << 15) - 1)
+#define GYRO_MIN	-(1 << 23)
+#define GYRO_MAX	((1 << 23) - 1)
+#define MAGNET_MIN	-(1 << 15)
+#define MAGNET_MAX	((1 << 15) - 1)
+
 /*
  * The device is setup with multiple input devices:
  * - A joypad with the buttons and sticks.
  * - The touch area which works as a touchscreen.
+ * - An accelerometer + gyroscope + magnetometer device.
  */
 
 struct drc {
 	struct input_dev *joy_input_dev;
 	struct input_dev *touch_input_dev;
+	struct input_dev *accel_input_dev;
 	struct hid_device *hdev;
 };
 
@@ -87,7 +97,7 @@ static int drc_raw_event(struct hid_device *hdev, struct hid_report *report,
 			 u8 *data, int len)
 {
 	struct drc *drc = hid_get_drvdata(hdev);
-	int i, x, y, pressure, base;
+	int i, x, y, z, pressure, base;
 	u32 buttons;
 
 	if (len != 128)
@@ -182,6 +192,31 @@ static int drc_raw_event(struct hid_device *hdev, struct hid_report *report,
 	}
 	input_sync(drc->touch_input_dev);
 
+	/* accelerometer */
+	x = (data[16] << 8) | data[15];
+	y = (data[18] << 8) | data[17];
+	z = (data[20] << 8) | data[19];
+	input_report_abs(drc->accel_input_dev, ABS_X, (int16_t)x);
+	input_report_abs(drc->accel_input_dev, ABS_Y, (int16_t)y);
+	input_report_abs(drc->accel_input_dev, ABS_Z, (int16_t)z);
+
+	/* gyroscope */
+	x = (data[23] << 24) | (data[22] << 16) | (data[21] << 8);
+	y = (data[26] << 24) | (data[25] << 16) | (data[24] << 8);
+	z = (data[29] << 24) | (data[28] << 16) | (data[27] << 8);
+	input_report_abs(drc->accel_input_dev, ABS_RX, x >> 8);
+	input_report_abs(drc->accel_input_dev, ABS_RY, y >> 8);
+	input_report_abs(drc->accel_input_dev, ABS_RZ, z >> 8);
+
+	/* magnetometer */
+	x = (data[31] << 8) | data[30];
+	y = (data[33] << 8) | data[32];
+	z = (data[35] << 8) | data[34];
+	input_report_abs(drc->accel_input_dev, ABS_THROTTLE, (int16_t)x);
+	input_report_abs(drc->accel_input_dev, ABS_RUDDER, (int16_t)y);
+	input_report_abs(drc->accel_input_dev, ABS_WHEEL, (int16_t)z);
+	input_sync(drc->accel_input_dev);
+
 	/* let hidraw and hiddev handle the report */
 	return 0;
 }
@@ -297,6 +332,40 @@ static bool drc_setup_touch(struct drc *drc,
 	return true;
 }
 
+static bool drc_setup_accel(struct drc *drc,
+			    struct hid_device *hdev)
+{
+	struct input_dev *input_dev;
+
+	input_dev = allocate_and_setup(hdev, DEVICE_NAME " accelerometer, gyroscope and magnetometer");
+	if (!input_dev)
+		return false;
+
+	drc->accel_input_dev = input_dev;
+
+	set_bit(INPUT_PROP_ACCELEROMETER, input_dev->propbit);
+
+	/* 1G accel is reported as about -7900 */
+	input_set_abs_params(input_dev, ABS_X, ACCEL_MIN, ACCEL_MAX, 0, 0);
+	input_set_abs_params(input_dev, ABS_Y, ACCEL_MIN, ACCEL_MAX, 0, 0);
+	input_set_abs_params(input_dev, ABS_Z, ACCEL_MIN, ACCEL_MAX, 0, 0);
+
+	/* gyroscope */
+	input_set_abs_params(input_dev, ABS_RX, GYRO_MIN, GYRO_MAX, 0, 0);
+	input_set_abs_params(input_dev, ABS_RY, GYRO_MIN, GYRO_MAX, 0, 0);
+	input_set_abs_params(input_dev, ABS_RZ, GYRO_MIN, GYRO_MAX, 0, 0);
+
+	/* magnetometer */
+	/* TODO: Figure out which ABS_* would make more sense to expose, or
+	 * maybe go for the iio subsystem?
+	 */
+	input_set_abs_params(input_dev, ABS_THROTTLE, MAGNET_MIN, MAGNET_MAX, 0, 0);
+	input_set_abs_params(input_dev, ABS_RUDDER, MAGNET_MIN, MAGNET_MAX, 0, 0);
+	input_set_abs_params(input_dev, ABS_WHEEL, MAGNET_MIN, MAGNET_MAX, 0, 0);
+
+	return true;
+}
+
 static int drc_probe(struct hid_device *hdev, const struct hid_device_id *id)
 {
 	struct drc *drc;
@@ -317,7 +386,8 @@ static int drc_probe(struct hid_device *hdev, const struct hid_device_id *id)
 	}
 
 	if (!drc_setup_joypad(drc, hdev) ||
-	    !drc_setup_touch(drc, hdev)) {
+	    !drc_setup_touch(drc, hdev) ||
+	    !drc_setup_accel(drc, hdev)) {
 		hid_err(hdev, "could not allocate interfaces\n");
 		return -ENOMEM;
 	}
@@ -329,7 +399,8 @@ static int drc_probe(struct hid_device *hdev, const struct hid_device_id *id)
 	}
 
 	ret = input_register_device(drc->joy_input_dev) ||
-	      input_register_device(drc->touch_input_dev);
+	      input_register_device(drc->touch_input_dev) ||
+	      input_register_device(drc->accel_input_dev);
 	if (ret) {
 		hid_err(hdev, "failed to register interfaces\n");
 		return ret;
-- 
2.31.1

[PATCH v2 4/4] HID: wiiu-drc: Add battery reporting

[Emmanuel Gil Peyrot]

On my DRC the values only go between 142 (battery LED blinking red
before shutdown) and 178 (charge LED stopping), it seems to be the same
on other units according to other testers.  This might be the raw
voltage value as reported by an ADC, so adding a linear interpolation
between two common battery voltage values.

A spinlock is used to avoid the battery level and status from being
reported unsynchronised.

Signed-off-by: Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
---
 drivers/hid/hid-wiiu-drc.c | 123 +++++++++++++++++++++++++++++++++++++
 1 file changed, 123 insertions(+)

diff --git a/drivers/hid/hid-wiiu-drc.c b/drivers/hid/hid-wiiu-drc.c
index a631d405119e..c1c883641b67 100644
--- a/drivers/hid/hid-wiiu-drc.c
+++ b/drivers/hid/hid-wiiu-drc.c
@@ -17,6 +17,8 @@
 #include <linux/input.h>
 #include <linux/minmax.h>
 #include <linux/module.h>
+#include <linux/power_supply.h>
+#include <linux/spinlock.h>
 #include "hid-ids.h"
 
 #define DEVICE_NAME	"Nintendo Wii U gamepad (DRC)"
@@ -71,6 +73,13 @@
 #define MAGNET_MIN	-(1 << 15)
 #define MAGNET_MAX	((1 << 15) - 1)
 
+/* ADC constants for the battery */
+#define BATTERY_CHARGING_BIT	BIT(6)
+#define BATTERY_MIN	142
+#define BATTERY_MAX	178
+#define VOLTAGE_MIN	3270000
+#define VOLTAGE_MAX	4100000
+
 /*
  * The device is setup with multiple input devices:
  * - A joypad with the buttons and sticks.
@@ -83,6 +92,12 @@ struct drc {
 	struct input_dev *touch_input_dev;
 	struct input_dev *accel_input_dev;
 	struct hid_device *hdev;
+
+	struct power_supply *battery;
+	struct power_supply_desc battery_desc;
+	spinlock_t battery_lock;
+	u8 battery_energy;
+	int battery_status;
 };
 
 /*
@@ -99,6 +114,7 @@ static int drc_raw_event(struct hid_device *hdev, struct hid_report *report,
 	struct drc *drc = hid_get_drvdata(hdev);
 	int i, x, y, z, pressure, base;
 	u32 buttons;
+	unsigned long flags;
 
 	if (len != 128)
 		return -EINVAL;
@@ -217,6 +233,17 @@ static int drc_raw_event(struct hid_device *hdev, struct hid_report *report,
 	input_report_abs(drc->accel_input_dev, ABS_WHEEL, (int16_t)z);
 	input_sync(drc->accel_input_dev);
 
+	/* battery */
+	spin_lock_irqsave(&drc->battery_lock, flags);
+	drc->battery_energy = data[5];
+	if (drc->battery_energy == BATTERY_MAX)
+		drc->battery_status = POWER_SUPPLY_STATUS_FULL;
+	else if (data[4] & BATTERY_CHARGING_BIT)
+		drc->battery_status = POWER_SUPPLY_STATUS_CHARGING;
+	else
+		drc->battery_status = POWER_SUPPLY_STATUS_DISCHARGING;
+	spin_unlock_irqrestore(&drc->battery_lock, flags);
+
 	/* let hidraw and hiddev handle the report */
 	return 0;
 }
@@ -366,6 +393,96 @@ static bool drc_setup_accel(struct drc *drc,
 	return true;
 }
 
+static enum power_supply_property drc_battery_props[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_VOLTAGE_MAX,
+	POWER_SUPPLY_PROP_VOLTAGE_MIN,
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_SCOPE,
+};
+
+static int drc_battery_get_property(struct power_supply *psy,
+				    enum power_supply_property psp,
+				    union power_supply_propval *val)
+{
+	struct drc *drc = power_supply_get_drvdata(psy);
+	unsigned long flags;
+	int ret = 0;
+	u8 battery_energy;
+	int battery_status;
+
+	spin_lock_irqsave(&drc->battery_lock, flags);
+	battery_energy = drc->battery_energy;
+	battery_status = drc->battery_status;
+	spin_unlock_irqrestore(&drc->battery_lock, flags);
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_STATUS:
+		val->intval = battery_status;
+		break;
+	case POWER_SUPPLY_PROP_PRESENT:
+		val->intval = 1;
+		break;
+	case POWER_SUPPLY_PROP_VOLTAGE_MAX:
+		val->intval = VOLTAGE_MAX;
+		break;
+	case POWER_SUPPLY_PROP_VOLTAGE_MIN:
+		val->intval = VOLTAGE_MIN;
+		break;
+	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+		val->intval = fixp_linear_interpolate(BATTERY_MIN, VOLTAGE_MIN,
+						      BATTERY_MAX, VOLTAGE_MAX,
+						      battery_energy);
+		break;
+	case POWER_SUPPLY_PROP_CAPACITY:
+		val->intval = fixp_linear_interpolate(BATTERY_MIN, 0,
+						      BATTERY_MAX, 100,
+						      battery_energy);
+		break;
+	case POWER_SUPPLY_PROP_SCOPE:
+		val->intval = POWER_SUPPLY_SCOPE_DEVICE;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	return ret;
+}
+
+static int drc_setup_battery(struct drc *drc,
+			     struct hid_device *hdev)
+{
+	struct power_supply_config psy_cfg = { .drv_data = drc, };
+	static atomic_t drc_num = ATOMIC_INIT(0);
+	int ret;
+
+	spin_lock_init(&drc->battery_lock);
+
+	drc->battery_desc.properties = drc_battery_props;
+	drc->battery_desc.num_properties = ARRAY_SIZE(drc_battery_props);
+	drc->battery_desc.get_property = drc_battery_get_property;
+	drc->battery_desc.type = POWER_SUPPLY_TYPE_BATTERY;
+	drc->battery_desc.use_for_apm = 0;
+
+	drc->battery_desc.name = devm_kasprintf(&hdev->dev, GFP_KERNEL,
+						"wiiu-drc-%i-battery", atomic_fetch_inc(&drc_num));
+	if (!drc->battery_desc.name)
+		return -ENOMEM;
+
+	drc->battery = devm_power_supply_register(&hdev->dev, &drc->battery_desc, &psy_cfg);
+	if (IS_ERR(drc->battery)) {
+		ret = PTR_ERR(drc->battery);
+		hid_err(hdev, "Unable to register battery device\n");
+		return ret;
+	}
+
+	power_supply_powers(drc->battery, &hdev->dev);
+
+	return 0;
+}
+
 static int drc_probe(struct hid_device *hdev, const struct hid_device_id *id)
 {
 	struct drc *drc;
@@ -392,6 +509,12 @@ static int drc_probe(struct hid_device *hdev, const struct hid_device_id *id)
 		return -ENOMEM;
 	}
 
+	ret = drc_setup_battery(drc, hdev);
+	if (ret) {
+		hid_err(hdev, "could not allocate battery interface\n");
+		return ret;
+	}
+
 	ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW | HID_CONNECT_DRIVER);
 	if (ret) {
 		hid_err(hdev, "hw start failed\n");
-- 
2.31.1