[PATCH v9 0/2] hid-steam driver with user mode client dection

[PATCH v9 0/2] hid-steam driver with user mode client dection

[Rodrigo Rivas Costa]

Hello! This is reroll v9 of the Steam Controller driver.

@Pierre-Loup, @Clément, could you please check if this driver is acceptable by
Valve? I think this could be the one ;-).

I've rolled back the synthetic LPAD diagonals. It happens that the actual
coordinates of the pads are rotated about 15 degrees to the center, but the
marks in the pad are aligned to 0/90 degrees. That, and my poor's man
trigonometry, makes clicking the diagonals quite unreliable.
Sorry for the noise, but now I think that we are better limiting ourselves to
the events emitted by the hardware, as is.

Other than that, I've doing some torture testing, with and without the Steam
Client running. I've changed:
 1. The way EPIPE is handled when sending a report: I've noticed that Steam
    Client retries up to 50 times, with little or no delay between them, so I do
    the same.
 2. I've added a fallback in case this driver is unable to get the serial number
    of the controller. Failures on any other report can be ignored safely. But
    failing to get the serial number was preventing the creating of the hidraw
    node (wired controller only), and that could prevent Steam Client from
    working. 
 3. I've received a mail from Valve with a bunch of constants for the
    protocol. Most are related to the setting of new mappings (that we do not
    need) and a few of the rest are deprecated. Anyway, I've renamed the
    constants STEAM_CMD_* to align them with the official names, and added a
    few more that were unknown to me, just for future reference. Still, commands
    used for enabling/disabling lizard mode are the same.

Best regards.

Changes in v9:
 * Remove synthetic diagonals for the DPAD (bad idea).
 * Rename protocol constants to follow Valve names.
 * Rewrite the retry fo steam_send_report() when EPIPE.
 * Add a fallback for failure getting the serial number.

Changes in v8:
 * Add constants for the protocol major magic numbers.
 * Disable/Enable margin of the rpad, together with the lizard-mode.
 * Synthesize diagonals for the DPAD.
 * Fix overflow with Y=-32768.
 * Make lizard_mode parameter a bool, dynamically updatable.

Changes in v7:
 * All the automatic lizard_mode stuff.
 * Added the lizard_mode parameter.
 * The patchset is reduced to 2 commits. The separation of the
   steam_get_serial command no longer makes sense, since I need the
   steam_send_cmd in the first commit to implement the lizard mode.
 * Change the input mapping to conform to Documentation/gamepad.rst.

(v6 was a RFC, it does not count).

Changes in v5:
 * Fix license SPDX to GPL-2.0+.
 * Minor stylistic changes (BIT(3) instead 0x08 and so on).

Changes in v4:
 * Add command to check the wireless connection status on probe, without
   waiting for a message (thanks to Clément Vuchener for the tip).
 * Removed the error code on redundant connection/disconnection messages. That
   was harmless but polluted dmesg.
 * Added buttons for touching the left-pad and right-pad.
 * Fixed a misplaced #include from 2/4 to 1/4.

Changes in v3:
 * Use RCU to do the dynamic connec/disconnect of wireless devices.
 * Remove entries in hid-quirks.c as they are no longer needed. This allows
   this module to be blacklisted without side effects.
 * Do not bypass the virtual keyboard/mouse HID devices to avoid breaking
   existing use cases (lizard mode). A user-space tool to do that is
   linked.
 * Fully separated axes for joystick and left-pad. As it happens.
 * Add fuzz values for left/right pad axes, they are a little wiggly.

Changes in v2:
 * Remove references to USB. Now the interesting interfaces are selected by
   looking for the ones with feature reports.
 * Feature reports buffers are allocated with hid_alloc_report_buf().
 * Feature report length is checked, to avoid overflows in case of
   corrupt/malicius USB devices.
 * Resolution added to the ABS axes.
 * A lot of minor cleanups.

Rodrigo Rivas Costa (2):
  HID: add driver for Valve Steam Controller
  HID: steam: add battery device.

 drivers/hid/Kconfig     |    8 +
 drivers/hid/Makefile    |    1 +
 drivers/hid/hid-ids.h   |    4 +
 drivers/hid/hid-steam.c | 1112 +++++++++++++++++++++++++++++++++++++++
 include/linux/hid.h     |    1 +
 5 files changed, 1126 insertions(+)
 create mode 100644 drivers/hid/hid-steam.c

-- 
2.17.0

[PATCH v9 1/2] HID: add driver for Valve Steam Controller

[Rodrigo Rivas Costa]

There are two ways to connect the Steam Controller: directly to the USB
or with the USB wireless adapter.  Both methods are similar, but the
wireless adapter can connect up to 4 devices at the same time.

The wired device will appear as 3 interfaces: a virtual mouse, a virtual
keyboard and a custom HID device.

The wireless device will appear as 5 interfaces: a virtual keyboard and
4 custom HID devices, that will remain silent until a device is actually
connected.

The custom HID device has a report descriptor with all vendor specific
usages, so the hid-generic is not very useful. In a PC/SteamBox Valve
Steam Client provices a software translation by using hidraw and a
creates a uinput virtual gamepad and XTest keyboard/mouse.

This driver intercepts the hidraw usage, so it can get out of the way
when the Steam Client is in use.

Signed-off-by: Rodrigo Rivas Costa <rodrigorivascosta@gmail.com>
---
 drivers/hid/Kconfig     |   8 +
 drivers/hid/Makefile    |   1 +
 drivers/hid/hid-ids.h   |   4 +
 drivers/hid/hid-steam.c | 973 ++++++++++++++++++++++++++++++++++++++++
 include/linux/hid.h     |   1 +
 5 files changed, 987 insertions(+)
 create mode 100644 drivers/hid/hid-steam.c

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 779c5ae47f36..de5f4849bfe4 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -811,6 +811,14 @@ config HID_SPEEDLINK
 	---help---
 	Support for Speedlink Vicious and Divine Cezanne mouse.
 
+config HID_STEAM
+	tristate "Steam Controller support"
+	depends on HID
+	---help---
+	Say Y here if you have a Steam Controller if you want to use it
+	without running the Steam Client. It supports both the wired and
+	the wireless adaptor.
+
 config HID_STEELSERIES
 	tristate "Steelseries SRW-S1 steering wheel support"
 	depends on HID
diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
index 235bd2a7b333..e146c257285a 100644
--- a/drivers/hid/Makefile
+++ b/drivers/hid/Makefile
@@ -94,6 +94,7 @@ obj-$(CONFIG_HID_SAMSUNG)	+= hid-samsung.o
 obj-$(CONFIG_HID_SMARTJOYPLUS)	+= hid-sjoy.o
 obj-$(CONFIG_HID_SONY)		+= hid-sony.o
 obj-$(CONFIG_HID_SPEEDLINK)	+= hid-speedlink.o
+obj-$(CONFIG_HID_STEAM)		+= hid-steam.o
 obj-$(CONFIG_HID_STEELSERIES)	+= hid-steelseries.o
 obj-$(CONFIG_HID_SUNPLUS)	+= hid-sunplus.o
 obj-$(CONFIG_HID_GREENASIA)	+= hid-gaff.o
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index a0baa5ba5b84..3014991e5d4b 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -987,6 +987,10 @@
 #define USB_VENDOR_ID_STANTUM_SITRONIX		0x1403
 #define USB_DEVICE_ID_MTP_SITRONIX		0x5001
 
+#define USB_VENDOR_ID_VALVE			0x28de
+#define USB_DEVICE_ID_STEAM_CONTROLLER		0x1102
+#define USB_DEVICE_ID_STEAM_CONTROLLER_WIRELESS	0x1142
+
 #define USB_VENDOR_ID_STEELSERIES	0x1038
 #define USB_DEVICE_ID_STEELSERIES_SRWS1	0x1410
 
diff --git a/drivers/hid/hid-steam.c b/drivers/hid/hid-steam.c
new file mode 100644
index 000000000000..36fc85714ea5
--- /dev/null
+++ b/drivers/hid/hid-steam.c
@@ -0,0 +1,973 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * HID driver for Valve Steam Controller
+ *
+ * Copyright (c) 2018 Rodrigo Rivas Costa <rodrigorivascosta@gmail.com>
+ *
+ * Supports both the wired and wireless interfaces.
+ *
+ * This controller has a builtin emulation of mouse and keyboard: the right pad
+ * can be used as a mouse, the shoulder buttons are mouse buttons, A and B
+ * buttons are ENTER and ESCAPE, and so on. This is implemented as additional
+ * HID interfaces.
+ *
+ * This is known as the "lizard mode", because apparently lizards like to use
+ * the computer from the coach, without a proper mouse and keyboard.
+ *
+ * This driver will disable the lizard mode when the input device is opened
+ * and re-enable it when the input device is closed, so as not to break user
+ * mode behaviour. The lizard_mode parameter can be used to change that.
+ *
+ * There are a few user space applications (notably Steam Client) that use
+ * the hidraw interface directly to create input devices (XTest, uinput...).
+ * In order to avoid breaking them this driver creates a layered hidraw device,
+ * so it can detect when the client is running and then:
+ *  - it will not send any command to the controller.
+ *  - this input device will be disabled, to avoid double input of the same
+ *    user action.
+ *
+ * For additional functions, such as changing the right-pad margin or switching
+ * the led, you can use the user-space tool at:
+ *
+ *   https://github.com/rodrigorc/steamctrl
+ */
+
+#include <linux/device.h>
+#include <linux/input.h>
+#include <linux/hid.h>
+#include <linux/module.h>
+#include <linux/workqueue.h>
+#include <linux/mutex.h>
+#include <linux/rcupdate.h>
+#include <linux/delay.h>
+#include "hid-ids.h"
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Rodrigo Rivas Costa <rodrigorivascosta@gmail.com>");
+
+static bool lizard_mode = true;
+
+static DEFINE_MUTEX(steam_devices_lock);
+static LIST_HEAD(steam_devices);
+
+#define STEAM_QUIRK_WIRELESS		BIT(0)
+
+/* Touch pads are 40 mm in diameter and 65535 units */
+#define STEAM_PAD_RESOLUTION 1638
+/* Trigger runs are about 5 mm and 256 units */
+#define STEAM_TRIGGER_RESOLUTION 51
+/* Joystick runs are about 5 mm and 256 units */
+#define STEAM_JOYSTICK_RESOLUTION 51
+
+#define STEAM_PAD_FUZZ 256
+
+/*
+ * Commands that can be sent in a feature report.
+ * Thanks to Valve for some valuable hints.
+ */
+#define STEAM_CMD_SET_MAPPINGS		0x80
+#define STEAM_CMD_CLEAR_MAPPINGS	0x81
+#define STEAM_CMD_GET_MAPPINGS		0x82
+#define STEAM_CMD_GET_ATTRIB		0x83
+#define STEAM_CMD_GET_ATTRIB_LABEL	0x84
+#define STEAM_CMD_DEFAULT_MAPPINGS	0x85
+#define STEAM_CMD_FACTORY_RESET		0x86
+#define STEAM_CMD_WRITE_REGISTER	0x87
+#define STEAM_CMD_CLEAR_REGISTER	0x88
+#define STEAM_CMD_READ_REGISTER		0x89
+#define STEAM_CMD_GET_REGISTER_LABEL	0x8a
+#define STEAM_CMD_GET_REGISTER_MAX	0x8b
+#define STEAM_CMD_GET_REGISTER_DEFAULT	0x8c
+#define STEAM_CMD_SET_MODE		0x8d
+#define STEAM_CMD_DEFAULT_MOUSE		0x8e
+#define STEAM_CMD_FORCEFEEDBAK		0x8f
+#define STEAM_CMD_REQUEST_COMM_STATUS	0xb4
+#define STEAM_CMD_GET_SERIAL		0xae
+
+/* Some useful register ids */
+#define STEAM_REG_LPAD_MODE		0x07
+#define STEAM_REG_RPAD_MODE		0x08
+#define STEAM_REG_RPAD_MARGIN		0x18
+#define STEAM_REG_LED			0x2d
+#define STEAM_REG_GYRO_MODE		0x30
+
+/* Raw event identifiers */
+#define STEAM_EV_INPUT_DATA		0x01
+#define STEAM_EV_CONNECT		0x03
+#define STEAM_EV_BATTERY		0x04
+
+/* Values for GYRO_MODE (bitmask) */
+#define STEAM_GYRO_MODE_OFF		0x0000
+#define STEAM_GYRO_MODE_STEERING	0x0001
+#define STEAM_GYRO_MODE_TILT		0x0002
+#define STEAM_GYRO_MODE_SEND_ORIENTATION	0x0004
+#define STEAM_GYRO_MODE_SEND_RAW_ACCEL		0x0008
+#define STEAM_GYRO_MODE_SEND_RAW_GYRO		0x0010
+
+/* Other random constants */
+#define STEAM_SERIAL_LEN 10
+
+struct steam_device {
+	struct list_head list;
+	spinlock_t lock;
+	struct hid_device *hdev, *client_hdev;
+	struct mutex mutex;
+	bool client_opened, input_opened;
+	struct input_dev __rcu *input;
+	unsigned long quirks;
+	struct work_struct work_connect;
+	bool connected;
+	char serial_no[STEAM_SERIAL_LEN + 1];
+};
+
+static int steam_recv_report(struct steam_device *steam,
+		u8 *data, int size)
+{
+	struct hid_report *r;
+	u8 *buf;
+	int ret;
+
+	r = steam->hdev->report_enum[HID_FEATURE_REPORT].report_id_hash[0];
+	if (hid_report_len(r) < 64)
+		return -EINVAL;
+
+	buf = hid_alloc_report_buf(r, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	/*
+	 * The report ID is always 0, so strip the first byte from the output.
+	 * hid_report_len() is not counting the report ID, so +1 to the length
+	 * or else we get a EOVERFLOW. We are safe from a buffer overflow
+	 * because hid_alloc_report_buf() allocates +7 bytes.
+	 */
+	ret = hid_hw_raw_request(steam->hdev, 0x00,
+			buf, hid_report_len(r) + 1,
+			HID_FEATURE_REPORT, HID_REQ_GET_REPORT);
+	if (ret > 0)
+		memcpy(data, buf + 1, min(size, ret - 1));
+	kfree(buf);
+	return ret;
+}
+
+static int steam_send_report(struct steam_device *steam,
+		u8 *cmd, int size)
+{
+	struct hid_report *r;
+	u8 *buf;
+	unsigned int retries = 50;
+	int ret;
+
+	r = steam->hdev->report_enum[HID_FEATURE_REPORT].report_id_hash[0];
+	if (hid_report_len(r) < 64)
+		return -EINVAL;
+
+	buf = hid_alloc_report_buf(r, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	/* The report ID is always 0 */
+	memcpy(buf + 1, cmd, size);
+
+	/*
+	 * Sometimes the wireless controller fails with EPIPE
+	 * when sending a feature report.
+	 * Doing a HID_REQ_GET_REPORT and waiting for a while
+	 * seems to fix that.
+	 */
+	do {
+		ret = hid_hw_raw_request(steam->hdev, 0,
+				buf, size + 1,
+				HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
+		if (ret != -EPIPE)
+			break;
+		msleep(20);
+	} while (--retries);
+
+	kfree(buf);
+	if (ret < 0)
+		hid_err(steam->hdev, "%s: error %d (%*ph)\n", __func__,
+				ret, size, cmd);
+	return ret;
+}
+
+static inline int steam_send_report_byte(struct steam_device *steam, u8 cmd)
+{
+	return steam_send_report(steam, &cmd, 1);
+}
+
+static int steam_write_registers(struct steam_device *steam,
+		/* u8 reg, u16 val */...)
+{
+	/* Send: 0x87 len (reg valLo valHi)* */
+	u8 reg;
+	u16 val;
+	u8 cmd[64] = {STEAM_CMD_WRITE_REGISTER, 0x00};
+	va_list args;
+
+	va_start(args, steam);
+	for (;;) {
+		reg = va_arg(args, int);
+		if (reg == 0)
+			break;
+		val = va_arg(args, int);
+		cmd[cmd[1] + 2] = reg;
+		cmd[cmd[1] + 3] = val & 0xff;
+		cmd[cmd[1] + 4] = val >> 8;
+		cmd[1] += 3;
+	}
+	va_end(args);
+
+	return steam_send_report(steam, cmd, 2 + cmd[1]);
+}
+
+static int steam_get_serial(struct steam_device *steam)
+{
+	/*
+	 * Send: 0xae 0x15 0x01
+	 * Recv: 0xae 0x15 0x01 serialnumber (10 chars)
+	 */
+	int ret;
+	u8 cmd[] = {STEAM_CMD_GET_SERIAL, 0x15, 0x01};
+	u8 reply[3 + STEAM_SERIAL_LEN + 1];
+
+	ret = steam_send_report(steam, cmd, sizeof(cmd));
+	if (ret < 0)
+		return ret;
+	ret = steam_recv_report(steam, reply, sizeof(reply));
+	if (ret < 0)
+		return ret;
+	if (reply[0] != 0xae || reply[1] != 0x15 || reply[2] != 0x01)
+		return -EIO;
+	reply[3 + STEAM_SERIAL_LEN] = 0;
+	strlcpy(steam->serial_no, reply + 3, sizeof(steam->serial_no));
+	return 0;
+}
+
+/*
+ * This command requests the wireless adaptor to post an event
+ * with the connection status. Useful if this driver is loaded when
+ * the controller is already connected.
+ */
+static inline int steam_request_conn_status(struct steam_device *steam)
+{
+	return steam_send_report_byte(steam, STEAM_CMD_REQUEST_COMM_STATUS);
+}
+
+static void steam_set_lizard_mode(struct steam_device *steam, bool enable)
+{
+	if (enable) {
+		/* enable esc, enter, cursors */
+		steam_send_report_byte(steam, STEAM_CMD_DEFAULT_MAPPINGS);
+		/* enable mouse */
+		steam_send_report_byte(steam, STEAM_CMD_DEFAULT_MOUSE);
+		steam_write_registers(steam,
+			STEAM_REG_RPAD_MARGIN, 0x01, /* enable margin */
+			0);
+	} else {
+		/* disable esc, enter, cursor */
+		steam_send_report_byte(steam, STEAM_CMD_CLEAR_MAPPINGS);
+		steam_write_registers(steam,
+			STEAM_REG_RPAD_MODE, 0x07, /* disable mouse */
+			STEAM_REG_RPAD_MARGIN, 0x00, /* disable margin */
+			0);
+	}
+}
+
+static void steam_update_lizard_mode(struct steam_device *steam)
+{
+	mutex_lock(&steam->mutex);
+	if (!steam->client_opened) {
+		if (steam->input_opened)
+			steam_set_lizard_mode(steam, false);
+		else
+			steam_set_lizard_mode(steam, lizard_mode);
+	}
+	mutex_unlock(&steam->mutex);
+}
+
+static int steam_input_open(struct input_dev *dev)
+{
+	struct steam_device *steam = input_get_drvdata(dev);
+	int ret;
+
+	ret = hid_hw_open(steam->hdev);
+	if (ret)
+		return ret;
+
+	mutex_lock(&steam->mutex);
+	steam->input_opened = true;
+	if (!steam->client_opened && lizard_mode)
+		steam_set_lizard_mode(steam, false);
+	mutex_unlock(&steam->mutex);
+	return 0;
+}
+
+static void steam_input_close(struct input_dev *dev)
+{
+	struct steam_device *steam = input_get_drvdata(dev);
+
+	mutex_lock(&steam->mutex);
+	steam->input_opened = false;
+	if (!steam->client_opened && lizard_mode)
+		steam_set_lizard_mode(steam, true);
+	mutex_unlock(&steam->mutex);
+
+	hid_hw_close(steam->hdev);
+}
+
+static int steam_register(struct steam_device *steam)
+{
+	struct hid_device *hdev = steam->hdev;
+	struct input_dev *input;
+	int ret;
+
+	rcu_read_lock();
+	input = rcu_dereference(steam->input);
+	rcu_read_unlock();
+	if (input) {
+		dbg_hid("%s: already connected\n", __func__);
+		return 0;
+	}
+
+	/*
+	 * Unlikely, but getting the serial could fail, and it is not so
+	 * important, so make up a serial number and go on.
+	 */
+	if (steam_get_serial(steam) < 0)
+		strlcpy(steam->serial_no, "XXXXXXXXXX",
+				sizeof(steam->serial_no));
+
+	hid_info(hdev, "Steam Controller '%s' connected",
+			steam->serial_no);
+
+	input = input_allocate_device();
+	if (!input)
+		return -ENOMEM;
+
+	input_set_drvdata(input, steam);
+	input->dev.parent = &hdev->dev;
+	input->open = steam_input_open;
+	input->close = steam_input_close;
+
+	input->name = (steam->quirks & STEAM_QUIRK_WIRELESS) ?
+		"Wireless Steam Controller" :
+		"Steam Controller";
+	input->phys = hdev->phys;
+	input->uniq = steam->serial_no;
+	input->id.bustype = hdev->bus;
+	input->id.vendor = hdev->vendor;
+	input->id.product = hdev->product;
+	input->id.version = hdev->version;
+
+	input_set_capability(input, EV_KEY, BTN_TR2);
+	input_set_capability(input, EV_KEY, BTN_TL2);
+	input_set_capability(input, EV_KEY, BTN_TR);
+	input_set_capability(input, EV_KEY, BTN_TL);
+	input_set_capability(input, EV_KEY, BTN_Y);
+	input_set_capability(input, EV_KEY, BTN_B);
+	input_set_capability(input, EV_KEY, BTN_X);
+	input_set_capability(input, EV_KEY, BTN_A);
+	input_set_capability(input, EV_KEY, BTN_DPAD_UP);
+	input_set_capability(input, EV_KEY, BTN_DPAD_RIGHT);
+	input_set_capability(input, EV_KEY, BTN_DPAD_LEFT);
+	input_set_capability(input, EV_KEY, BTN_DPAD_DOWN);
+	input_set_capability(input, EV_KEY, BTN_SELECT);
+	input_set_capability(input, EV_KEY, BTN_MODE);
+	input_set_capability(input, EV_KEY, BTN_START);
+	input_set_capability(input, EV_KEY, BTN_GEAR_DOWN);
+	input_set_capability(input, EV_KEY, BTN_GEAR_UP);
+	input_set_capability(input, EV_KEY, BTN_THUMBR);
+	input_set_capability(input, EV_KEY, BTN_THUMBL);
+	input_set_capability(input, EV_KEY, BTN_THUMB);
+	input_set_capability(input, EV_KEY, BTN_THUMB2);
+
+	input_set_abs_params(input, ABS_HAT2Y, 0, 255, 0, 0);
+	input_set_abs_params(input, ABS_HAT2X, 0, 255, 0, 0);
+	input_set_abs_params(input, ABS_X, -32767, 32767, 0, 0);
+	input_set_abs_params(input, ABS_Y, -32767, 32767, 0, 0);
+	input_set_abs_params(input, ABS_RX, -32767, 32767,
+			STEAM_PAD_FUZZ, 0);
+	input_set_abs_params(input, ABS_RY, -32767, 32767,
+			STEAM_PAD_FUZZ, 0);
+	input_set_abs_params(input, ABS_HAT0X, -32767, 32767,
+			STEAM_PAD_FUZZ, 0);
+	input_set_abs_params(input, ABS_HAT0Y, -32767, 32767,
+			STEAM_PAD_FUZZ, 0);
+	input_abs_set_res(input, ABS_X, STEAM_JOYSTICK_RESOLUTION);
+	input_abs_set_res(input, ABS_Y, STEAM_JOYSTICK_RESOLUTION);
+	input_abs_set_res(input, ABS_RX, STEAM_PAD_RESOLUTION);
+	input_abs_set_res(input, ABS_RY, STEAM_PAD_RESOLUTION);
+	input_abs_set_res(input, ABS_HAT0X, STEAM_PAD_RESOLUTION);
+	input_abs_set_res(input, ABS_HAT0Y, STEAM_PAD_RESOLUTION);
+	input_abs_set_res(input, ABS_HAT2Y, STEAM_TRIGGER_RESOLUTION);
+	input_abs_set_res(input, ABS_HAT2X, STEAM_TRIGGER_RESOLUTION);
+
+	ret = input_register_device(input);
+	if (ret)
+		goto input_register_fail;
+
+	rcu_assign_pointer(steam->input, input);
+
+	return 0;
+
+input_register_fail:
+	input_free_device(input);
+	return ret;
+}
+
+static void steam_unregister(struct steam_device *steam)
+{
+	struct input_dev *input;
+
+	rcu_read_lock();
+	input = rcu_dereference(steam->input);
+	rcu_read_unlock();
+
+	if (input) {
+		RCU_INIT_POINTER(steam->input, NULL);
+		synchronize_rcu();
+		hid_info(steam->hdev, "Steam Controller '%s' disconnected",
+				steam->serial_no);
+		input_unregister_device(input);
+	}
+}
+
+static void steam_work_connect_cb(struct work_struct *work)
+{
+	struct steam_device *steam = container_of(work, struct steam_device,
+							work_connect);
+	unsigned long flags;
+	bool connected;
+	int ret;
+
+	spin_lock_irqsave(&steam->lock, flags);
+	connected = steam->connected;
+	spin_unlock_irqrestore(&steam->lock, flags);
+
+	if (connected) {
+		ret = steam_register(steam);
+		if (ret) {
+			hid_err(steam->hdev,
+				"%s:steam_register failed with error %d\n",
+				__func__, ret);
+		}
+	} else {
+		steam_unregister(steam);
+	}
+}
+
+static bool steam_is_valve_interface(struct hid_device *hdev)
+{
+	struct hid_report_enum *rep_enum;
+
+	/*
+	 * The wired device creates 3 interfaces:
+	 *  0: emulated mouse.
+	 *  1: emulated keyboard.
+	 *  2: the real game pad.
+	 * The wireless device creates 5 interfaces:
+	 *  0: emulated keyboard.
+	 *  1-4: slots where up to 4 real game pads will be connected to.
+	 * We know which one is the real gamepad interface because they are the
+	 * only ones with a feature report.
+	 */
+	rep_enum = &hdev->report_enum[HID_FEATURE_REPORT];
+	return !list_empty(&rep_enum->report_list);
+}
+
+static int steam_client_ll_parse(struct hid_device *hdev)
+{
+	struct steam_device *steam = hid_get_drvdata(hdev);
+
+	return hid_parse_report(hdev, steam->hdev->dev_rdesc,
+			steam->hdev->dev_rsize);
+}
+
+static int steam_client_ll_start(struct hid_device *hdev)
+{
+	return 0;
+}
+
+static void steam_client_ll_stop(struct hid_device *hdev)
+{
+}
+
+static int steam_client_ll_open(struct hid_device *hdev)
+{
+	struct steam_device *steam = hid_get_drvdata(hdev);
+	int ret;
+
+	ret = hid_hw_open(steam->hdev);
+	if (ret)
+		return ret;
+
+	mutex_lock(&steam->mutex);
+	steam->client_opened = true;
+	mutex_unlock(&steam->mutex);
+	return ret;
+}
+
+static void steam_client_ll_close(struct hid_device *hdev)
+{
+	struct steam_device *steam = hid_get_drvdata(hdev);
+
+	mutex_lock(&steam->mutex);
+	steam->client_opened = false;
+	if (steam->input_opened)
+		steam_set_lizard_mode(steam, false);
+	else
+		steam_set_lizard_mode(steam, lizard_mode);
+	mutex_unlock(&steam->mutex);
+
+	hid_hw_close(steam->hdev);
+}
+
+static int steam_client_ll_raw_request(struct hid_device *hdev,
+				unsigned char reportnum, u8 *buf,
+				size_t count, unsigned char report_type,
+				int reqtype)
+{
+	struct steam_device *steam = hid_get_drvdata(hdev);
+
+	return hid_hw_raw_request(steam->hdev, reportnum, buf, count,
+			report_type, reqtype);
+}
+
+static struct hid_ll_driver steam_client_ll_driver = {
+	.parse = steam_client_ll_parse,
+	.start = steam_client_ll_start,
+	.stop = steam_client_ll_stop,
+	.open = steam_client_ll_open,
+	.close = steam_client_ll_close,
+	.raw_request = steam_client_ll_raw_request,
+};
+
+static struct hid_device *steam_create_client_hid(struct hid_device *hdev)
+{
+	struct hid_device *client_hdev;
+
+	client_hdev = hid_allocate_device();
+	if (IS_ERR(client_hdev))
+		return client_hdev;
+
+	client_hdev->ll_driver = &steam_client_ll_driver;
+	client_hdev->dev.parent = hdev->dev.parent;
+	client_hdev->bus = hdev->bus;
+	client_hdev->vendor = hdev->vendor;
+	client_hdev->product = hdev->product;
+	strlcpy(client_hdev->name, hdev->name,
+			sizeof(client_hdev->name));
+	strlcpy(client_hdev->phys, hdev->phys,
+			sizeof(client_hdev->phys));
+	/*
+	 * Since we use the same device info than the real interface to
+	 * trick userspace, we will be calling steam_probe recursively.
+	 * We need to recognize the client interface somehow.
+	 */
+	client_hdev->group = HID_GROUP_STEAM;
+	return client_hdev;
+}
+
+static int steam_probe(struct hid_device *hdev,
+				const struct hid_device_id *id)
+{
+	struct steam_device *steam;
+	int ret;
+
+	ret = hid_parse(hdev);
+	if (ret) {
+		hid_err(hdev,
+			"%s:parse of hid interface failed\n", __func__);
+		return ret;
+	}
+
+	/*
+	 * The virtual client_dev is only used for hidraw.
+	 * Also avoid the recursive probe.
+	 */
+	if (hdev->group == HID_GROUP_STEAM)
+		return hid_hw_start(hdev, HID_CONNECT_HIDRAW);
+	/*
+	 * The non-valve interfaces (mouse and keyboard emulation) are
+	 * connected without changes.
+	 */
+	if (!steam_is_valve_interface(hdev))
+		return hid_hw_start(hdev, HID_CONNECT_DEFAULT);
+
+	steam = devm_kzalloc(&hdev->dev, sizeof(*steam), GFP_KERNEL);
+	if (!steam) {
+		ret = -ENOMEM;
+		goto steam_alloc_fail;
+	}
+	steam->hdev = hdev;
+	hid_set_drvdata(hdev, steam);
+	spin_lock_init(&steam->lock);
+	mutex_init(&steam->mutex);
+	steam->quirks = id->driver_data;
+	INIT_WORK(&steam->work_connect, steam_work_connect_cb);
+
+	steam->client_hdev = steam_create_client_hid(hdev);
+	if (IS_ERR(steam->client_hdev)) {
+		ret = PTR_ERR(steam->client_hdev);
+		goto client_hdev_fail;
+	}
+	hid_set_drvdata(steam->client_hdev, steam);
+
+	/*
+	 * With the real steam controller interface, do not connect hidraw.
+	 * Instead, create the client_hid and connect that.
+	 */
+	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_HIDRAW);
+	if (ret)
+		goto hid_hw_start_fail;
+
+	ret = hid_add_device(steam->client_hdev);
+	if (ret)
+		goto client_hdev_add_fail;
+
+	if (steam->quirks & STEAM_QUIRK_WIRELESS) {
+		ret = hid_hw_open(hdev);
+		if (ret) {
+			hid_err(hdev,
+				"%s:hid_hw_open for wireless\n",
+				__func__);
+			goto hid_hw_open_fail;
+		}
+		hid_info(hdev, "Steam wireless receiver connected");
+		steam_request_conn_status(steam);
+	} else {
+		ret = steam_register(steam);
+		if (ret) {
+			hid_err(hdev,
+				"%s:steam_register failed with error %d\n",
+				__func__, ret);
+			goto input_register_fail;
+		}
+	}
+
+	mutex_lock(&steam_devices_lock);
+	steam_update_lizard_mode(steam);
+	list_add(&steam->list, &steam_devices);
+	mutex_unlock(&steam_devices_lock);
+
+	return 0;
+
+hid_hw_open_fail:
+input_register_fail:
+client_hdev_add_fail:
+	hid_hw_stop(hdev);
+hid_hw_start_fail:
+	hid_destroy_device(steam->client_hdev);
+client_hdev_fail:
+	cancel_work_sync(&steam->work_connect);
+steam_alloc_fail:
+	hid_err(hdev, "%s: failed with error %d\n",
+			__func__, ret);
+	return ret;
+}
+
+static void steam_remove(struct hid_device *hdev)
+{
+	struct steam_device *steam = hid_get_drvdata(hdev);
+
+	if (!steam || hdev->group == HID_GROUP_STEAM) {
+		hid_hw_stop(hdev);
+		return;
+	}
+
+	mutex_lock(&steam_devices_lock);
+	list_del(&steam->list);
+	mutex_unlock(&steam_devices_lock);
+
+	hid_destroy_device(steam->client_hdev);
+	steam->client_opened = false;
+	cancel_work_sync(&steam->work_connect);
+	if (steam->quirks & STEAM_QUIRK_WIRELESS) {
+		hid_info(hdev, "Steam wireless receiver disconnected");
+		hid_hw_close(hdev);
+	}
+	hid_hw_stop(hdev);
+	steam_unregister(steam);
+}
+
+static void steam_do_connect_event(struct steam_device *steam, bool connected)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&steam->lock, flags);
+	steam->connected = connected;
+	spin_unlock_irqrestore(&steam->lock, flags);
+
+	if (schedule_work(&steam->work_connect) == 0)
+		dbg_hid("%s: connected=%d event already queued\n",
+				__func__, connected);
+}
+
+/*
+ * Some input data in the protocol has the opposite sign.
+ * Clamp the values to 32767..-32767 so that the range is
+ * symmetrical and can be negated safely.
+ */
+static inline s16 steam_le16(u8 *data)
+{
+	s16 x = (s16) le16_to_cpup((__le16 *)data);
+
+	return x == -32768 ? -32767 : x;
+}
+
+/*
+ * The size for this message payload is 60.
+ * The known values are:
+ *  (* values are not sent through wireless)
+ *  (* accelerator/gyro is disabled by default)
+ *  Offset| Type  | Mapped to |Meaning
+ * -------+-------+-----------+--------------------------
+ *  4-7   | u32   | --        | sequence number
+ *  8-10  | 24bit | see below | buttons
+ *  11    | u8    | ABS_HAT2Y | left trigger
+ *  12    | u8    | ABS_HAT2X | right trigger
+ *  13-15 | --    | --        | always 0
+ *  16-17 | s16   | ABS_X/ABS_HAT0X     | X value
+ *  18-19 | s16   | ABS_Y/ABS_HAT0Y     | Y value
+ *  20-21 | s16   | ABS_RX    | right-pad X value
+ *  22-23 | s16   | ABS_RY    | right-pad Y value
+ *  24-25 | s16   | --        | * left trigger
+ *  26-27 | s16   | --        | * right trigger
+ *  28-29 | s16   | --        | * accelerometer X value
+ *  30-31 | s16   | --        | * accelerometer Y value
+ *  32-33 | s16   | --        | * accelerometer Z value
+ *  34-35 | s16   | --        | gyro X value
+ *  36-36 | s16   | --        | gyro Y value
+ *  38-39 | s16   | --        | gyro Z value
+ *  40-41 | s16   | --        | quaternion W value
+ *  42-43 | s16   | --        | quaternion X value
+ *  44-45 | s16   | --        | quaternion Y value
+ *  46-47 | s16   | --        | quaternion Z value
+ *  48-49 | --    | --        | always 0
+ *  50-51 | s16   | --        | * left trigger (uncalibrated)
+ *  52-53 | s16   | --        | * right trigger (uncalibrated)
+ *  54-55 | s16   | --        | * joystick X value (uncalibrated)
+ *  56-57 | s16   | --        | * joystick Y value (uncalibrated)
+ *  58-59 | s16   | --        | * left-pad X value
+ *  60-61 | s16   | --        | * left-pad Y value
+ *  62-63 | u16   | --        | * battery voltage
+ *
+ * The buttons are:
+ *  Bit  | Mapped to  | Description
+ * ------+------------+--------------------------------
+ *  8.0  | BTN_TR2    | right trigger fully pressed
+ *  8.1  | BTN_TL2    | left trigger fully pressed
+ *  8.2  | BTN_TR     | right shoulder
+ *  8.3  | BTN_TL     | left shoulder
+ *  8.4  | BTN_Y      | button Y
+ *  8.5  | BTN_B      | button B
+ *  8.6  | BTN_X      | button X
+ *  8.7  | BTN_A      | button A
+ *  9.0  | BTN_DPAD_UP    | lef-pad up
+ *  9.1  | BTN_DPAD_RIGHT | lef-pad right
+ *  9.2  | BTN_DPAD_LEFT  | lef-pad left
+ *  9.3  | BTN_DPAD_DOWN  | lef-pad down
+ *  9.4  | BTN_SELECT | menu left
+ *  9.5  | BTN_MODE   | steam logo
+ *  9.6  | BTN_START  | menu right
+ *  9.7  | BTN_GEAR_DOWN | left back lever
+ * 10.0  | BTN_GEAR_UP   | right back lever
+ * 10.1  | --         | left-pad clicked
+ * 10.2  | BTN_THUMBR | right-pad clicked
+ * 10.3  | BTN_THUMB  | left-pad touched (but see explanation below)
+ * 10.4  | BTN_THUMB2 | right-pad touched
+ * 10.5  | --         | unknown
+ * 10.6  | BTN_THUMBL | joystick clicked
+ * 10.7  | --         | lpad_and_joy
+ */
+
+static void steam_do_input_event(struct steam_device *steam,
+		struct input_dev *input, u8 *data)
+{
+	/* 24 bits of buttons */
+	u8 b8, b9, b10;
+	s16 x, y;
+	bool lpad_touched, lpad_and_joy;
+
+	b8 = data[8];
+	b9 = data[9];
+	b10 = data[10];
+
+	input_report_abs(input, ABS_HAT2Y, data[11]);
+	input_report_abs(input, ABS_HAT2X, data[12]);
+
+	/*
+	 * These two bits tells how to interpret the values X and Y.
+	 * lpad_and_joy tells that the joystick and the lpad are used at the
+	 * same time.
+	 * lpad_touched tells whether X/Y are to be read as lpad coord or
+	 * joystick values.
+	 * (lpad_touched || lpad_and_joy) tells if the lpad is really touched.
+	 */
+	lpad_touched = b10 & BIT(3);
+	lpad_and_joy = b10 & BIT(7);
+	x = steam_le16(data + 16);
+	y = -steam_le16(data + 18);
+
+	input_report_abs(input, lpad_touched ? ABS_HAT0X : ABS_X, x);
+	input_report_abs(input, lpad_touched ? ABS_HAT0Y : ABS_Y, y);
+	/* Check if joystick is centered */
+	if (lpad_touched && !lpad_and_joy) {
+		input_report_abs(input, ABS_X, 0);
+		input_report_abs(input, ABS_Y, 0);
+	}
+	/* Check if lpad is untouched */
+	if (!(lpad_touched || lpad_and_joy)) {
+		input_report_abs(input, ABS_HAT0X, 0);
+		input_report_abs(input, ABS_HAT0Y, 0);
+	}
+
+	input_report_abs(input, ABS_RX, steam_le16(data + 20));
+	input_report_abs(input, ABS_RY, -steam_le16(data + 22));
+
+	input_event(input, EV_KEY, BTN_TR2, !!(b8 & BIT(0)));
+	input_event(input, EV_KEY, BTN_TL2, !!(b8 & BIT(1)));
+	input_event(input, EV_KEY, BTN_TR, !!(b8 & BIT(2)));
+	input_event(input, EV_KEY, BTN_TL, !!(b8 & BIT(3)));
+	input_event(input, EV_KEY, BTN_Y, !!(b8 & BIT(4)));
+	input_event(input, EV_KEY, BTN_B, !!(b8 & BIT(5)));
+	input_event(input, EV_KEY, BTN_X, !!(b8 & BIT(6)));
+	input_event(input, EV_KEY, BTN_A, !!(b8 & BIT(7)));
+	input_event(input, EV_KEY, BTN_SELECT, !!(b9 & BIT(4)));
+	input_event(input, EV_KEY, BTN_MODE, !!(b9 & BIT(5)));
+	input_event(input, EV_KEY, BTN_START, !!(b9 & BIT(6)));
+	input_event(input, EV_KEY, BTN_GEAR_DOWN, !!(b9 & BIT(7)));
+	input_event(input, EV_KEY, BTN_GEAR_UP, !!(b10 & BIT(0)));
+	input_event(input, EV_KEY, BTN_THUMBR, !!(b10 & BIT(2)));
+	input_event(input, EV_KEY, BTN_THUMBL, !!(b10 & BIT(6)));
+	input_event(input, EV_KEY, BTN_THUMB, lpad_touched || lpad_and_joy);
+	input_event(input, EV_KEY, BTN_THUMB2, !!(b10 & BIT(4)));
+	input_event(input, EV_KEY, BTN_DPAD_UP, !!(b9 & BIT(0)));
+	input_event(input, EV_KEY, BTN_DPAD_RIGHT, !!(b9 & BIT(1)));
+	input_event(input, EV_KEY, BTN_DPAD_LEFT, !!(b9 & BIT(2)));
+	input_event(input, EV_KEY, BTN_DPAD_DOWN, !!(b9 & BIT(3)));
+
+	input_sync(input);
+}
+
+static int steam_raw_event(struct hid_device *hdev,
+			struct hid_report *report, u8 *data,
+			int size)
+{
+	struct steam_device *steam = hid_get_drvdata(hdev);
+	struct input_dev *input;
+
+	if (!steam)
+		return 0;
+
+	if (steam->client_opened)
+		hid_input_report(steam->client_hdev, HID_FEATURE_REPORT,
+				data, size, 0);
+	/*
+	 * All messages are size=64, all values little-endian.
+	 * The format is:
+	 *  Offset| Meaning
+	 * -------+--------------------------------------------
+	 *  0-1   | always 0x01, 0x00, maybe protocol version?
+	 *  2     | type of message
+	 *  3     | length of the real payload (not checked)
+	 *  4-n   | payload data, depends on the type
+	 *
+	 * There are these known types of message:
+	 *  0x01: input data (60 bytes)
+	 *  0x03: wireless connect/disconnect (1 byte)
+	 *  0x04: battery status (11 bytes)
+	 */
+
+	if (size != 64 || data[0] != 1 || data[1] != 0)
+		return 0;
+
+	switch (data[2]) {
+	case STEAM_EV_INPUT_DATA:
+		if (steam->client_opened)
+			return 0;
+		rcu_read_lock();
+		input = rcu_dereference(steam->input);
+		if (likely(input)) {
+			steam_do_input_event(steam, input, data);
+		} else {
+			dbg_hid("%s: input data without connect event\n",
+					__func__);
+			steam_do_connect_event(steam, true);
+		}
+		rcu_read_unlock();
+		break;
+	case STEAM_EV_CONNECT:
+		/*
+		 * The payload of this event is a single byte:
+		 *  0x01: disconnected.
+		 *  0x02: connected.
+		 */
+		switch (data[4]) {
+		case 0x01:
+			steam_do_connect_event(steam, false);
+			break;
+		case 0x02:
+			steam_do_connect_event(steam, true);
+			break;
+		}
+		break;
+	case STEAM_EV_BATTERY:
+		/* TODO: battery info */
+		break;
+	}
+	return 0;
+}
+
+static int steam_param_set_lizard_mode(const char *val,
+					const struct kernel_param *kp)
+{
+	struct steam_device *steam;
+	int ret;
+
+	ret = param_set_bool(val, kp);
+	if (ret)
+		return ret;
+
+	mutex_lock(&steam_devices_lock);
+	list_for_each_entry(steam, &steam_devices, list) {
+		steam_update_lizard_mode(steam);
+	}
+	mutex_unlock(&steam_devices_lock);
+	return 0;
+}
+
+static const struct kernel_param_ops steam_lizard_mode_ops = {
+	.set	= steam_param_set_lizard_mode,
+	.get	= param_get_bool,
+};
+
+module_param_cb(lizard_mode, &steam_lizard_mode_ops, &lizard_mode, 0644);
+MODULE_PARM_DESC(lizard_mode,
+	"Enable mouse and keyboard emulation (lizard mode) when the gamepad is not in use");
+
+static const struct hid_device_id steam_controllers[] = {
+	{ /* Wired Steam Controller */
+	  HID_USB_DEVICE(USB_VENDOR_ID_VALVE,
+		USB_DEVICE_ID_STEAM_CONTROLLER)
+	},
+	{ /* Wireless Steam Controller */
+	  HID_USB_DEVICE(USB_VENDOR_ID_VALVE,
+		USB_DEVICE_ID_STEAM_CONTROLLER_WIRELESS),
+	  .driver_data = STEAM_QUIRK_WIRELESS
+	},
+	{}
+};
+
+MODULE_DEVICE_TABLE(hid, steam_controllers);
+
+static struct hid_driver steam_controller_driver = {
+	.name = "hid-steam",
+	.id_table = steam_controllers,
+	.probe = steam_probe,
+	.remove = steam_remove,
+	.raw_event = steam_raw_event,
+};
+
+module_hid_driver(steam_controller_driver);
diff --git a/include/linux/hid.h b/include/linux/hid.h
index d491027a7c22..5e5d76589954 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -364,6 +364,7 @@ struct hid_item {
 #define HID_GROUP_RMI				0x0100
 #define HID_GROUP_WACOM				0x0101
 #define HID_GROUP_LOGITECH_DJ_DEVICE		0x0102
+#define HID_GROUP_STEAM				0x0103
 
 /*
  * HID protocol status
-- 
2.17.0

[PATCH v9 2/2] HID: steam: add battery device.

[Rodrigo Rivas Costa]

The wireless Steam Controller is battery operated, so add the battery
device and power information.
---
 drivers/hid/hid-steam.c | 141 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 140 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/hid-steam.c b/drivers/hid/hid-steam.c
index 36fc85714ea5..af7ebb618867 100644
--- a/drivers/hid/hid-steam.c
+++ b/drivers/hid/hid-steam.c
@@ -40,6 +40,7 @@
 #include <linux/mutex.h>
 #include <linux/rcupdate.h>
 #include <linux/delay.h>
+#include <linux/power_supply.h>
 #include "hid-ids.h"
 
 MODULE_LICENSE("GPL");
@@ -118,6 +119,10 @@ struct steam_device {
 	struct work_struct work_connect;
 	bool connected;
 	char serial_no[STEAM_SERIAL_LEN + 1];
+	struct power_supply_desc battery_desc;
+	struct power_supply __rcu *battery;
+	u8 battery_charge;
+	u16 voltage;
 };
 
 static int steam_recv_report(struct steam_device *steam,
@@ -316,6 +321,85 @@ static void steam_input_close(struct input_dev *dev)
 	hid_hw_close(steam->hdev);
 }
 
+static enum power_supply_property steam_battery_props[] = {
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_SCOPE,
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_CAPACITY,
+};
+
+static int steam_battery_get_property(struct power_supply *psy,
+				enum power_supply_property psp,
+				union power_supply_propval *val)
+{
+	struct steam_device *steam = power_supply_get_drvdata(psy);
+	unsigned long flags;
+	s16 volts;
+	u8 batt;
+	int ret = 0;
+
+	spin_lock_irqsave(&steam->lock, flags);
+	volts = steam->voltage;
+	batt = steam->battery_charge;
+	spin_unlock_irqrestore(&steam->lock, flags);
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_PRESENT:
+		val->intval = 1;
+		break;
+	case POWER_SUPPLY_PROP_SCOPE:
+		val->intval = POWER_SUPPLY_SCOPE_DEVICE;
+		break;
+	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+		val->intval = volts * 1000; /* mV -> uV */
+		break;
+	case POWER_SUPPLY_PROP_CAPACITY:
+		val->intval = batt;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	return ret;
+}
+
+static int steam_battery_register(struct steam_device *steam)
+{
+	struct power_supply *battery;
+	struct power_supply_config battery_cfg = { .drv_data = steam, };
+	unsigned long flags;
+	int ret;
+
+	steam->battery_desc.type = POWER_SUPPLY_TYPE_BATTERY;
+	steam->battery_desc.properties = steam_battery_props;
+	steam->battery_desc.num_properties = ARRAY_SIZE(steam_battery_props);
+	steam->battery_desc.get_property = steam_battery_get_property;
+	steam->battery_desc.name = devm_kasprintf(&steam->hdev->dev,
+			GFP_KERNEL, "steam-controller-%s-battery",
+			steam->serial_no);
+	if (!steam->battery_desc.name)
+		return -ENOMEM;
+
+	/* avoid the warning of 0% battery while waiting for the first info */
+	spin_lock_irqsave(&steam->lock, flags);
+	steam->voltage = 3000;
+	steam->battery_charge = 100;
+	spin_unlock_irqrestore(&steam->lock, flags);
+
+	battery = power_supply_register(&steam->hdev->dev,
+			&steam->battery_desc, &battery_cfg);
+	if (IS_ERR(battery)) {
+		ret = PTR_ERR(battery);
+		hid_err(steam->hdev,
+				"%s:power_supply_register failed with error %d\n",
+				__func__, ret);
+		return ret;
+	}
+	rcu_assign_pointer(steam->battery, battery);
+	power_supply_powers(battery, &steam->hdev->dev);
+	return 0;
+}
+
 static int steam_register(struct steam_device *steam)
 {
 	struct hid_device *hdev = steam->hdev;
@@ -409,6 +493,10 @@ static int steam_register(struct steam_device *steam)
 
 	rcu_assign_pointer(steam->input, input);
 
+	/* ignore battery errors, we can live without it */
+	if (steam->quirks & STEAM_QUIRK_WIRELESS)
+		steam_battery_register(steam);
+
 	return 0;
 
 input_register_fail:
@@ -419,11 +507,18 @@ static int steam_register(struct steam_device *steam)
 static void steam_unregister(struct steam_device *steam)
 {
 	struct input_dev *input;
+	struct power_supply *battery;
 
 	rcu_read_lock();
 	input = rcu_dereference(steam->input);
+	battery = rcu_dereference(steam->battery);
 	rcu_read_unlock();
 
+	if (battery) {
+		RCU_INIT_POINTER(steam->battery, NULL);
+		synchronize_rcu();
+		power_supply_unregister(battery);
+	}
 	if (input) {
 		RCU_INIT_POINTER(steam->input, NULL);
 		synchronize_rcu();
@@ -851,12 +946,44 @@ static void steam_do_input_event(struct steam_device *steam,
 	input_sync(input);
 }
 
+/*
+ * The size for this message payload is 11.
+ * The known values are:
+ *  Offset| Type  | Meaning
+ * -------+-------+---------------------------
+ *  4-7   | u32   | sequence number
+ *  8-11  | --    | always 0
+ *  12-13 | u16   | voltage (mV)
+ *  14    | u8    | battery percent
+ */
+static void steam_do_battery_event(struct steam_device *steam,
+		struct power_supply *battery, u8 *data)
+{
+	unsigned long flags;
+
+	s16 volts = steam_le16(data + 12);
+	u8 batt = data[14];
+
+	/* Creating the battery may have failed */
+	rcu_read_lock();
+	battery = rcu_dereference(steam->battery);
+	if (likely(battery)) {
+		spin_lock_irqsave(&steam->lock, flags);
+		steam->voltage = volts;
+		steam->battery_charge = batt;
+		spin_unlock_irqrestore(&steam->lock, flags);
+		power_supply_changed(battery);
+	}
+	rcu_read_unlock();
+}
+
 static int steam_raw_event(struct hid_device *hdev,
 			struct hid_report *report, u8 *data,
 			int size)
 {
 	struct steam_device *steam = hid_get_drvdata(hdev);
 	struct input_dev *input;
+	struct power_supply *battery;
 
 	if (!steam)
 		return 0;
@@ -914,7 +1041,19 @@ static int steam_raw_event(struct hid_device *hdev,
 		}
 		break;
 	case STEAM_EV_BATTERY:
-		/* TODO: battery info */
+		if (steam->quirks & STEAM_QUIRK_WIRELESS) {
+			rcu_read_lock();
+			battery = rcu_dereference(steam->battery);
+			if (likely(battery)) {
+				steam_do_battery_event(steam, battery, data);
+			} else {
+				dbg_hid(
+					"%s: battery data without connect event\n",
+					__func__);
+				steam_do_connect_event(steam, true);
+			}
+			rcu_read_unlock();
+		}
 		break;
 	}
 	return 0;
-- 
2.17.0

Re: [PATCH v9 0/2] hid-steam driver with user mode client dection

[Jiri Kosina]

On Mon, 16 Apr 2018, Rodrigo Rivas Costa wrote:

> Hello! This is reroll v9 of the Steam Controller driver.
> 
> @Pierre-Loup, @Clément, could you please check if this driver is acceptable by
> Valve? I think this could be the one ;-).
> 
> I've rolled back the synthetic LPAD diagonals. It happens that the actual
> coordinates of the pads are rotated about 15 degrees to the center, but the
> marks in the pad are aligned to 0/90 degrees. That, and my poor's man
> trigonometry, makes clicking the diagonals quite unreliable.
> Sorry for the noise, but now I think that we are better limiting ourselves to
> the events emitted by the hardware, as is.
> 
> Other than that, I've doing some torture testing, with and without the Steam
> Client running. I've changed:
>  1. The way EPIPE is handled when sending a report: I've noticed that Steam
>     Client retries up to 50 times, with little or no delay between them, so I do
>     the same.
>  2. I've added a fallback in case this driver is unable to get the serial number
>     of the controller. Failures on any other report can be ignored safely. But
>     failing to get the serial number was preventing the creating of the hidraw
>     node (wired controller only), and that could prevent Steam Client from
>     working. 
>  3. I've received a mail from Valve with a bunch of constants for the
>     protocol. Most are related to the setting of new mappings (that we do not
>     need) and a few of the rest are deprecated. Anyway, I've renamed the
>     constants STEAM_CMD_* to align them with the official names, and added a
>     few more that were unknown to me, just for future reference. Still, commands
>     used for enabling/disabling lizard mode are the same.

If noone has any objections (last chance to raise them), I'll be queuing 
this for 4.18.

Thanks,

-- 
Jiri Kosina
SUSE Labs

Re: [PATCH v9 0/2] hid-steam driver with user mode client dection

[Rodrigo Rivas Costa]

On Fri, May 04, 2018 at 10:12:51AM +0200, Jiri Kosina wrote:
> On Mon, 16 Apr 2018, Rodrigo Rivas Costa wrote:
> 
> > Hello! This is reroll v9 of the Steam Controller driver.
> > 
> > @Pierre-Loup, @Clément, could you please check if this driver is acceptable by
> > Valve? I think this could be the one ;-).
> > 
> > I've rolled back the synthetic LPAD diagonals. It happens that the actual
> > coordinates of the pads are rotated about 15 degrees to the center, but the
> > marks in the pad are aligned to 0/90 degrees. That, and my poor's man
> > trigonometry, makes clicking the diagonals quite unreliable.
> > Sorry for the noise, but now I think that we are better limiting ourselves to
> > the events emitted by the hardware, as is.
> > 
> > Other than that, I've doing some torture testing, with and without the Steam
> > Client running. I've changed:
> >  1. The way EPIPE is handled when sending a report: I've noticed that Steam
> >     Client retries up to 50 times, with little or no delay between them, so I do
> >     the same.
> >  2. I've added a fallback in case this driver is unable to get the serial number
> >     of the controller. Failures on any other report can be ignored safely. But
> >     failing to get the serial number was preventing the creating of the hidraw
> >     node (wired controller only), and that could prevent Steam Client from
> >     working. 
> >  3. I've received a mail from Valve with a bunch of constants for the
> >     protocol. Most are related to the setting of new mappings (that we do not
> >     need) and a few of the rest are deprecated. Anyway, I've renamed the
> >     constants STEAM_CMD_* to align them with the official names, and added a
> >     few more that were unknown to me, just for future reference. Still, commands
> >     used for enabling/disabling lizard mode are the same.
> 
> If noone has any objections (last chance to raise them), I'll be queuing 
> this for 4.18.

That would be great, thanks!

Now that my distro upgraded to 4.16, without the hid-quirks array, I've been
testing it a bit more. 

It works great, but I've noticed that I've missed a couple of lines when
creating the client hdev.  It doesn't seem to cause any harm, and anyway 'type'
and 'country' are currently both 0 in my controller; only 'version' is visibly
different but who uses that?

Anyway, this would be the change, I don't know if it is worth a whole reroll...

diff --git a/drivers/hid/hid-steam.c b/drivers/hid/hid-steam.c
index af7ebb618867..cb86cc834201 100644
--- a/drivers/hid/hid-steam.c
+++ b/drivers/hid/hid-steam.c
@@ -651,6 +651,9 @@ static struct hid_device *steam_create_client_hid(struct hid_device *hdev)
        client_hdev->bus = hdev->bus;
        client_hdev->vendor = hdev->vendor;
        client_hdev->product = hdev->product;
+       client_hdev->version = hdev->version;
+       client_hdev->type = hdev->type;
+       client_hdev->country = hdev->country;
        strlcpy(client_hdev->name, hdev->name,
                        sizeof(client_hdev->name));
        strlcpy(client_hdev->phys, hdev->phys,

Best regards,
--
Rodrigo Rivas Costa

> 
> Thanks,
> 
> -- 
> Jiri Kosina
> SUSE Labs
> 

Re: [PATCH v9 0/2] hid-steam driver with user mode client dection

[Jiri Kosina]

On Fri, 4 May 2018, Rodrigo Rivas Costa wrote:

> > If noone has any objections (last chance to raise them), I'll be 
> > queuing this for 4.18.
> 
> That would be great, thanks!
> 
> Now that my distro upgraded to 4.16, without the hid-quirks array, I've been
> testing it a bit more. 
> 
> It works great, but I've noticed that I've missed a couple of lines when
> creating the client hdev.  It doesn't seem to cause any harm, and anyway 'type'
> and 'country' are currently both 0 in my controller; only 'version' is visibly
> different but who uses that?
> 
> Anyway, this would be the change, I don't know if it is worth a whole reroll...

I've put this on top of your patches and queued in for-4.18/hid-steam. 
Thanks,

-- 
Jiri Kosina
SUSE Labs