[PATCH 0/2] HID: steelseries: Add Rival 3 Wireless battery reporting

[PATCH 0/2] HID: steelseries: Add Rival 3 Wireless battery reporting

[Martin Oberleiter]

The SteelSeries Rival 3 Wireless mouse reports its battery level on
request through its 2.4 GHz receiver, using the protocol rivalcfg
implements. This series exposes it as a power supply.

Patch 1 makes HID_STEELSERIES select POWER_SUPPLY, which the Arctis
headset support already needs and which patch 2 relies on as well.

Patch 2 adds the battery reporting. Desktops currently show the mouse's
battery with a keyboard icon: upower picks the kind from the sibling
input devices and prefers the mouse's auxiliary keyboard interface. That
is a upower heuristic and will be reported there separately.

Tested on a Rival 3 Wireless (receiver 1038:1830) over a night with the
mouse switched off and on again.

The series was written with the help of an AI coding assistant (Claude
Code); details are in the changelog of patch 2.

---
Martin Oberleiter (2):
      HID: steelseries: Select POWER_SUPPLY
      HID: steelseries: Add Rival 3 Wireless battery reporting

 drivers/hid/Kconfig           |   5 +-
 drivers/hid/hid-ids.h         |   1 +
 drivers/hid/hid-steelseries.c | 277 +++++++++++++++++++++++++++++++++++++++++-
 3 files changed, 277 insertions(+), 6 deletions(-)
---
base-commit: 720806515cb6921ab05caaa6f470f7054b56385e
change-id: 20261030-rival3-battery-ad17cd19e128

Best regards,
--  
Martin Oberleiter <martin.oberleiter@netixx.it>

[PATCH 0/2] HID: steelseries: Add Rival 3 Wireless battery reporting

[Martin Oberleiter via B4 Relay]

The SteelSeries Rival 3 Wireless mouse reports its battery level on
request through its 2.4 GHz receiver, using the protocol rivalcfg
implements. This series exposes it as a power supply.

Patch 1 makes HID_STEELSERIES select POWER_SUPPLY, which the Arctis
headset support already needs and which patch 2 relies on as well.

Patch 2 adds the battery reporting. Desktops currently show the mouse's
battery with a keyboard icon: upower picks the kind from the sibling
input devices and prefers the mouse's auxiliary keyboard interface. That
is a upower heuristic and will be reported there separately.

Tested on a Rival 3 Wireless (receiver 1038:1830) over a night with the
mouse switched off and on again.

The series was written with the help of an AI coding assistant (Claude
Code); details are in the changelog of patch 2.

---
Martin Oberleiter (2):
      HID: steelseries: Select POWER_SUPPLY
      HID: steelseries: Add Rival 3 Wireless battery reporting

 drivers/hid/Kconfig           |   5 +-
 drivers/hid/hid-ids.h         |   1 +
 drivers/hid/hid-steelseries.c | 277 +++++++++++++++++++++++++++++++++++++++++-
 3 files changed, 277 insertions(+), 6 deletions(-)
---
base-commit: 720806515cb6921ab05caaa6f470f7054b56385e
change-id: 20261030-rival3-battery-ad17cd19e128

Best regards,
--  
Martin Oberleiter <martin.oberleiter@netixx.it>

[PATCH 1/2] HID: steelseries: Select POWER_SUPPLY

[Martin Oberleiter]

The Arctis headset support registers a power supply for the headset
battery, but HID_STEELSERIES does not select POWER_SUPPLY, and
power_supply_register() has no stub, so a build with POWER_SUPPLY=n
fails to link. Select it, like the other HID drivers that report a
battery.

Fixes: a0c76896c3fb ("HID: steelseries: Add support for Arctis 1 XBox")
Signed-off-by: Martin Oberleiter <martin.oberleiter@netixx.it>
---
 drivers/hid/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 2481bc01c..4d48da4f5 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -1214,6 +1214,7 @@ config STEAM_FF
 config HID_STEELSERIES
 	tristate "Steelseries devices support"
 	depends on USB_HID
+	select POWER_SUPPLY
 	help
 	Support for Steelseries SRW-S1 steering wheel, and the Steelseries
 	Arctis 1 Wireless for XBox, Arctis 7 (2018), Arctis 9, and Arctis

-- 
2.56.0

[PATCH 1/2] HID: steelseries: Select POWER_SUPPLY

[Martin Oberleiter via B4 Relay]

From: Martin Oberleiter <martin.oberleiter@netixx.it>

The Arctis headset support registers a power supply for the headset
battery, but HID_STEELSERIES does not select POWER_SUPPLY, and
power_supply_register() has no stub, so a build with POWER_SUPPLY=n
fails to link. Select it, like the other HID drivers that report a
battery.

Fixes: a0c76896c3fb ("HID: steelseries: Add support for Arctis 1 XBox")
Signed-off-by: Martin Oberleiter <martin.oberleiter@netixx.it>
---
 drivers/hid/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 2481bc01c..4d48da4f5 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -1214,6 +1214,7 @@ config STEAM_FF
 config HID_STEELSERIES
 	tristate "Steelseries devices support"
 	depends on USB_HID
+	select POWER_SUPPLY
 	help
 	Support for Steelseries SRW-S1 steering wheel, and the Steelseries
 	Arctis 1 Wireless for XBox, Arctis 7 (2018), Arctis 9, and Arctis

-- 
2.56.0

[PATCH 2/2] HID: steelseries: Add Rival 3 Wireless battery reporting

[Martin Oberleiter]

The Rival 3 Wireless mouse in 2.4 GHz mode (receiver 1038:1830) reports
its battery level on request: an output report AA 01 on the vendor
interface (interface 3) is answered through the receiver about 80 ms
later by an input report holding the level in percent in the first
byte and a charging flag in the third, followed by zero padding. While
the mouse is off or asleep, the receiver does not answer. This is the
protocol rivalcfg uses.

Register a power supply on that interface and poll it from a delayed
work: every 10 minutes while the mouse answers, every minute while it
does not, and right after resume. As the reply carries no command echo,
it is only accepted while one is awaited and if it has the expected
shape. If the mouse does not answer within 500 ms, the status becomes
unknown and the last level is kept. Until the first reply, report 100%
with an unknown status, as the Arctis headset support does, to avoid a
spurious low battery warning. The mouse's other interfaces are left
closed until userspace opens them, as with hid-generic.

The status polling in hid-steelseries-arctis is not reused: it is built
around headsets with sync and async interfaces and a connection status,
while the mouse needs a single request with a reply timeout.

Userspace talking to interface 3 through hidraw at the same time (e.g.
rivalcfg) can see the driver's replies, and a reply to its own command
with the same shape would be taken as a battery reply.

Tested on a Rival 3 Wireless with its 2.4 GHz receiver: the battery
shows up with the level the mouse reports, the status becomes unknown
while the mouse is off, and the level is back within a minute of
switching it on. Mouse input is unaffected.

The protocol was verified on the device and the driver and this
changelog were written with the help of an AI coding assistant (Claude
Code).

Signed-off-by: Martin Oberleiter <martin.oberleiter@netixx.it>
---
 drivers/hid/Kconfig           |   4 +-
 drivers/hid/hid-ids.h         |   1 +
 drivers/hid/hid-steelseries.c | 277 +++++++++++++++++++++++++++++++++++++++++-
 3 files changed, 276 insertions(+), 6 deletions(-)

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 4d48da4f5..cd52f7304 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -1216,9 +1216,9 @@ config HID_STEELSERIES
 	depends on USB_HID
 	select POWER_SUPPLY
 	help
-	Support for Steelseries SRW-S1 steering wheel, and the Steelseries
+	Support for Steelseries SRW-S1 steering wheel, the Steelseries
 	Arctis 1 Wireless for XBox, Arctis 7 (2018), Arctis 9, and Arctis
-	Nova headsets.
+	Nova headsets, and battery reporting for the Rival 3 Wireless mouse.
 
 config HID_SUNPLUS
 	tristate "Sunplus wireless desktop"
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 91319aa65..ca19f00eb 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -1437,6 +1437,7 @@
 #define USB_DEVICE_ID_STEELSERIES_ARCTIS_NOVA_7_X_GEN2_3	0x22ad
 #define USB_DEVICE_ID_STEELSERIES_MSI_KLC   0x1122
 #define USB_DEVICE_ID_STEELSERIES_MSI_ALC   0x1161
+#define USB_DEVICE_ID_STEELSERIES_RIVAL_3_WIRELESS	0x1830
 
 #define USB_VENDOR_ID_SUN		0x0430
 #define USB_DEVICE_ID_RARITAN_KVM_DONGLE	0xcdab
diff --git a/drivers/hid/hid-steelseries.c b/drivers/hid/hid-steelseries.c
index 7292da031..9fa70d21f 100644
--- a/drivers/hid/hid-steelseries.c
+++ b/drivers/hid/hid-steelseries.c
@@ -8,19 +8,25 @@
 /*
  */
 
+#include <linux/completion.h>
 #include <linux/device.h>
 #include <linux/dmi.h>
 #include <linux/hid.h>
 #include <linux/module.h>
+#include <linux/power_supply.h>
 #include <linux/usb.h>
 #include <linux/leds.h>
 #include <linux/led-class-multicolor.h>
 #include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
 
 #include "hid-ids.h"
 
 #define STEELSERIES_SRWS1		BIT(0)
 #define STEELSERIES_MSI_RGB		BIT(1)
+#define STEELSERIES_RIVAL3_WIRELESS	BIT(2)
 
 #define STEELSERIES_MSI_RGB_WVALUE 0x0300 /* Feature report, ID 0 */
 #define STEELSERIES_MSI_RGB_REPORT_LEN 524
@@ -42,6 +48,18 @@ struct steelseries_device {
 	struct mutex rgb_lock; /* protects rgb_buf */
 	u8 *rgb_buf;
 #endif
+
+	/* Rival 3 Wireless battery, on the vendor interface only */
+	bool battery_iface;
+	struct power_supply *battery;
+	struct power_supply_desc battery_desc;
+	struct delayed_work battery_work;
+	struct completion battery_reply;
+	spinlock_t battery_lock; /* protects the fields below */
+	bool battery_awaiting_reply;
+	bool battery_online;
+	bool battery_charging;
+	u8 battery_capacity;
 };
 
 #if IS_BUILTIN(CONFIG_LEDS_CLASS) || \
@@ -564,6 +582,206 @@ static int steelseries_msi_rgb_register(struct steelseries_device *sd)
 }
 #endif
 
+/*
+ * Rival 3 Wireless (2.4 GHz receiver): the battery level is read with an
+ * output report AA 01 on the vendor interface. The mouse answers through
+ * the receiver about 80 ms later with an input report whose first byte is
+ * the level in percent and whose third byte is the charging flag. There is
+ * no command echo, so a reply is only accepted while one is awaited. While
+ * the mouse is off or asleep, the receiver does not answer at all.
+ */
+#define STEELSERIES_RIVAL3_WIRELESS_IFACE		3
+#define STEELSERIES_RIVAL3_WIRELESS_REPLY_TIMEOUT_MS	500
+#define STEELSERIES_RIVAL3_WIRELESS_POLL_ONLINE_MS	(10 * 60 * 1000)
+#define STEELSERIES_RIVAL3_WIRELESS_POLL_OFFLINE_MS	(60 * 1000)
+
+static bool steelseries_rival3_is_battery_iface(struct hid_device *hdev)
+{
+	struct usb_interface *intf = steelseries_hid_to_usb_intf(hdev);
+
+	return intf && intf->cur_altsetting->desc.bInterfaceNumber ==
+		STEELSERIES_RIVAL3_WIRELESS_IFACE;
+}
+
+static const enum power_supply_property steelseries_rival3_battery_props[] = {
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_SCOPE,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_MODEL_NAME,
+	POWER_SUPPLY_PROP_MANUFACTURER,
+};
+
+static int steelseries_rival3_battery_get_property(struct power_supply *psy,
+						   enum power_supply_property psp,
+						   union power_supply_propval *val)
+{
+	struct steelseries_device *sd = power_supply_get_drvdata(psy);
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&sd->battery_lock, flags);
+	switch (psp) {
+	case POWER_SUPPLY_PROP_PRESENT:
+		val->intval = 1;
+		break;
+	case POWER_SUPPLY_PROP_STATUS:
+		if (!sd->battery_online)
+			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
+		else if (sd->battery_charging)
+			val->intval = POWER_SUPPLY_STATUS_CHARGING;
+		else
+			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
+		break;
+	case POWER_SUPPLY_PROP_SCOPE:
+		val->intval = POWER_SUPPLY_SCOPE_DEVICE;
+		break;
+	case POWER_SUPPLY_PROP_CAPACITY:
+		val->intval = sd->battery_capacity;
+		break;
+	case POWER_SUPPLY_PROP_MODEL_NAME:
+		val->strval = "Rival 3 Wireless";
+		break;
+	case POWER_SUPPLY_PROP_MANUFACTURER:
+		val->strval = "SteelSeries";
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	spin_unlock_irqrestore(&sd->battery_lock, flags);
+
+	return ret;
+}
+
+static void steelseries_rival3_battery_work(struct work_struct *work)
+{
+	struct steelseries_device *sd = container_of(work,
+			struct steelseries_device, battery_work.work);
+	static const u8 request[] = { 0x00, 0xaa, 0x01 }; /* report ID 0 */
+	bool was_online, was_charging, online, changed;
+	unsigned long flags, timeout;
+	u8 old_capacity;
+	u8 *buf;
+	int ret;
+
+	spin_lock_irqsave(&sd->battery_lock, flags);
+	was_online = sd->battery_online;
+	was_charging = sd->battery_charging;
+	old_capacity = sd->battery_capacity;
+	spin_unlock_irqrestore(&sd->battery_lock, flags);
+
+	buf = kmemdup(request, sizeof(request), GFP_KERNEL);
+	if (!buf) {
+		ret = -ENOMEM;
+		goto update;
+	}
+
+	spin_lock_irqsave(&sd->battery_lock, flags);
+	reinit_completion(&sd->battery_reply);
+	sd->battery_awaiting_reply = true;
+	spin_unlock_irqrestore(&sd->battery_lock, flags);
+
+	ret = hid_hw_raw_request(sd->hdev, 0x00, buf, sizeof(request),
+				 HID_OUTPUT_REPORT, HID_REQ_SET_REPORT);
+	kfree(buf);
+	if (ret >= 0) {
+		timeout = msecs_to_jiffies(STEELSERIES_RIVAL3_WIRELESS_REPLY_TIMEOUT_MS);
+		ret = wait_for_completion_timeout(&sd->battery_reply, timeout) ? 0 : -ETIMEDOUT;
+	}
+
+update:
+	spin_lock_irqsave(&sd->battery_lock, flags);
+	/* A reply may still have arrived right after the timeout. */
+	if (ret && sd->battery_awaiting_reply) {
+		/* Keep the last level; the mouse is off or asleep. */
+		sd->battery_awaiting_reply = false;
+		sd->battery_online = false;
+	} else {
+		ret = 0;
+	}
+	online = sd->battery_online;
+	changed = online != was_online ||
+		  sd->battery_charging != was_charging ||
+		  sd->battery_capacity != old_capacity;
+	spin_unlock_irqrestore(&sd->battery_lock, flags);
+
+	if (ret)
+		hid_dbg(sd->hdev, "No battery reply: %d\n", ret);
+	if (changed)
+		power_supply_changed(sd->battery);
+
+	schedule_delayed_work(&sd->battery_work, msecs_to_jiffies(online ?
+			STEELSERIES_RIVAL3_WIRELESS_POLL_ONLINE_MS :
+			STEELSERIES_RIVAL3_WIRELESS_POLL_OFFLINE_MS));
+}
+
+static int steelseries_rival3_battery_register(struct steelseries_device *sd)
+{
+	struct power_supply_config battery_cfg = { .drv_data = sd, };
+	struct hid_device *hdev = sd->hdev;
+	struct power_supply *battery;
+
+	spin_lock_init(&sd->battery_lock);
+	init_completion(&sd->battery_reply);
+	INIT_DELAYED_WORK(&sd->battery_work, steelseries_rival3_battery_work);
+	/* Avoid a 0% warning before the first reply; status stays unknown. */
+	sd->battery_capacity = 100;
+
+	sd->battery_desc.type = POWER_SUPPLY_TYPE_BATTERY;
+	sd->battery_desc.properties = steelseries_rival3_battery_props;
+	sd->battery_desc.num_properties = ARRAY_SIZE(steelseries_rival3_battery_props);
+	sd->battery_desc.get_property = steelseries_rival3_battery_get_property;
+	sd->battery_desc.name = devm_kasprintf(&hdev->dev, GFP_KERNEL,
+					       "steelseries_mouse_battery_%s",
+					       hdev->uniq[0] ? hdev->uniq :
+					       dev_name(&hdev->dev));
+	if (!sd->battery_desc.name)
+		return -ENOMEM;
+
+	battery = devm_power_supply_register(&hdev->dev, &sd->battery_desc,
+					     &battery_cfg);
+	if (IS_ERR(battery))
+		return PTR_ERR(battery);
+
+	power_supply_powers(battery, &hdev->dev);
+	sd->battery = battery;
+	sd->battery_iface = true;
+
+	return 0;
+}
+
+static int steelseries_raw_event(struct hid_device *hdev,
+				 struct hid_report *report, u8 *data, int size)
+{
+	struct steelseries_device *sd;
+	unsigned long flags;
+
+	if (hdev->product != USB_DEVICE_ID_STEELSERIES_RIVAL_3_WIRELESS)
+		return 0;
+
+	sd = hid_get_drvdata(hdev);
+	if (!sd || !sd->battery_iface)
+		return 0;
+
+	/* level, 0, charging, then zero padding */
+	if (size < 3 || data[0] > 100 || data[1] ||
+	    memchr_inv(data + 3, 0, size - 3))
+		return 0;
+
+	spin_lock_irqsave(&sd->battery_lock, flags);
+	if (sd->battery_awaiting_reply) {
+		sd->battery_capacity = data[0];
+		sd->battery_charging = data[2];
+		sd->battery_online = true;
+		sd->battery_awaiting_reply = false;
+		complete(&sd->battery_reply);
+	}
+	spin_unlock_irqrestore(&sd->battery_lock, flags);
+
+	return 0;
+}
+
 static int steelseries_probe(struct hid_device *hdev, const struct hid_device_id *id)
 {
 	struct steelseries_device *sd;
@@ -593,17 +811,38 @@ static int steelseries_probe(struct hid_device *hdev, const struct hid_device_id
 		}
 	}
 
+	if (sd->quirks & STEELSERIES_RIVAL3_WIRELESS &&
+	    !steelseries_rival3_is_battery_iface(hdev))
+		sd->quirks &= ~STEELSERIES_RIVAL3_WIRELESS;
+
 	ret = hid_parse(hdev);
 	if (ret)
 		return ret;
 
+	if (sd->quirks & STEELSERIES_RIVAL3_WIRELESS) {
+		ret = steelseries_rival3_battery_register(sd);
+		if (ret) {
+			hid_warn(hdev,
+				 "Failed to register battery: %d, continuing without battery reporting\n",
+				 ret);
+			sd->quirks &= ~STEELSERIES_RIVAL3_WIRELESS;
+		}
+	}
+
 	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
 	if (ret)
 		return ret;
 
-	ret = hid_hw_open(hdev);
-	if (ret)
-		goto err_stop;
+	/* Only the Rival 3 Wireless battery interface needs to stay open. */
+	if (hdev->product != USB_DEVICE_ID_STEELSERIES_RIVAL_3_WIRELESS ||
+	    sd->battery_iface) {
+		ret = hid_hw_open(hdev);
+		if (ret)
+			goto err_stop;
+	}
+
+	if (sd->battery_iface)
+		schedule_delayed_work(&sd->battery_work, msecs_to_jiffies(1000));
 
 	if (sd->quirks & STEELSERIES_MSI_RGB) {
 		ret = steelseries_msi_rgb_register(sd);
@@ -624,6 +863,8 @@ static int steelseries_probe(struct hid_device *hdev, const struct hid_device_id
 
 static void steelseries_remove(struct hid_device *hdev)
 {
+	struct steelseries_device *sd;
+
 	if (hdev->product == USB_DEVICE_ID_STEELSERIES_SRWS1) {
 #if IS_BUILTIN(CONFIG_LEDS_CLASS) || \
     (IS_MODULE(CONFIG_LEDS_CLASS) && IS_MODULE(CONFIG_HID_STEELSERIES))
@@ -632,10 +873,32 @@ static void steelseries_remove(struct hid_device *hdev)
 		return;
 	}
 
-	hid_hw_close(hdev);
+	sd = hid_get_drvdata(hdev);
+	if (sd->battery_iface)
+		cancel_delayed_work_sync(&sd->battery_work);
+
+	if (hdev->product != USB_DEVICE_ID_STEELSERIES_RIVAL_3_WIRELESS ||
+	    sd->battery_iface)
+		hid_hw_close(hdev);
 	hid_hw_stop(hdev);
 }
 
+static int steelseries_resume(struct hid_device *hdev)
+{
+	struct steelseries_device *sd;
+
+	if (hdev->product != USB_DEVICE_ID_STEELSERIES_RIVAL_3_WIRELESS)
+		return 0;
+
+	/* Polls during suspend fail, so do not wait for the next one. */
+	sd = hid_get_drvdata(hdev);
+	if (sd && sd->battery_iface)
+		mod_delayed_work(system_wq, &sd->battery_work,
+				 msecs_to_jiffies(1000));
+
+	return 0;
+}
+
 static const __u8 *steelseries_srws1_report_fixup(struct hid_device *hdev,
 		__u8 *rdesc, unsigned int *rsize)
 {
@@ -656,6 +919,9 @@ static const struct hid_device_id steelseries_devices[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_STEELSERIES, USB_DEVICE_ID_STEELSERIES_SRWS1),
 	  .driver_data = STEELSERIES_SRWS1 },
 
+	{ HID_USB_DEVICE(USB_VENDOR_ID_STEELSERIES, USB_DEVICE_ID_STEELSERIES_RIVAL_3_WIRELESS),
+	  .driver_data = STEELSERIES_RIVAL3_WIRELESS },
+
 #if STEELSERIES_HAS_LEDS_MULTICOLOR
 	{ /* MSI Raider A18 KLC */
 	  HID_USB_DEVICE(USB_VENDOR_ID_STEELSERIES, USB_DEVICE_ID_STEELSERIES_MSI_KLC),
@@ -675,6 +941,9 @@ static struct hid_driver steelseries_driver = {
 	.id_table = steelseries_devices,
 	.probe = steelseries_probe,
 	.remove = steelseries_remove,
+	.raw_event = steelseries_raw_event,
+	.resume = pm_ptr(steelseries_resume),
+	.reset_resume = pm_ptr(steelseries_resume),
 	.report_fixup = steelseries_srws1_report_fixup,
 };
 

-- 
2.56.0

[PATCH 2/2] HID: steelseries: Add Rival 3 Wireless battery reporting

[Martin Oberleiter via B4 Relay]

From: Martin Oberleiter <martin.oberleiter@netixx.it>

The Rival 3 Wireless mouse in 2.4 GHz mode (receiver 1038:1830) reports
its battery level on request: an output report AA 01 on the vendor
interface (interface 3) is answered through the receiver about 80 ms
later by an input report holding the level in percent in the first
byte and a charging flag in the third, followed by zero padding. While
the mouse is off or asleep, the receiver does not answer. This is the
protocol rivalcfg uses.

Register a power supply on that interface and poll it from a delayed
work: every 10 minutes while the mouse answers, every minute while it
does not, and right after resume. As the reply carries no command echo,
it is only accepted while one is awaited and if it has the expected
shape. If the mouse does not answer within 500 ms, the status becomes
unknown and the last level is kept. Until the first reply, report 100%
with an unknown status, as the Arctis headset support does, to avoid a
spurious low battery warning. The mouse's other interfaces are left
closed until userspace opens them, as with hid-generic.

The status polling in hid-steelseries-arctis is not reused: it is built
around headsets with sync and async interfaces and a connection status,
while the mouse needs a single request with a reply timeout.

Userspace talking to interface 3 through hidraw at the same time (e.g.
rivalcfg) can see the driver's replies, and a reply to its own command
with the same shape would be taken as a battery reply.

Tested on a Rival 3 Wireless with its 2.4 GHz receiver: the battery
shows up with the level the mouse reports, the status becomes unknown
while the mouse is off, and the level is back within a minute of
switching it on. Mouse input is unaffected.

The protocol was verified on the device and the driver and this
changelog were written with the help of an AI coding assistant (Claude
Code).

Signed-off-by: Martin Oberleiter <martin.oberleiter@netixx.it>
---
 drivers/hid/Kconfig           |   4 +-
 drivers/hid/hid-ids.h         |   1 +
 drivers/hid/hid-steelseries.c | 277 +++++++++++++++++++++++++++++++++++++++++-
 3 files changed, 276 insertions(+), 6 deletions(-)

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 4d48da4f5..cd52f7304 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -1216,9 +1216,9 @@ config HID_STEELSERIES
 	depends on USB_HID
 	select POWER_SUPPLY
 	help
-	Support for Steelseries SRW-S1 steering wheel, and the Steelseries
+	Support for Steelseries SRW-S1 steering wheel, the Steelseries
 	Arctis 1 Wireless for XBox, Arctis 7 (2018), Arctis 9, and Arctis
-	Nova headsets.
+	Nova headsets, and battery reporting for the Rival 3 Wireless mouse.
 
 config HID_SUNPLUS
 	tristate "Sunplus wireless desktop"
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 91319aa65..ca19f00eb 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -1437,6 +1437,7 @@
 #define USB_DEVICE_ID_STEELSERIES_ARCTIS_NOVA_7_X_GEN2_3	0x22ad
 #define USB_DEVICE_ID_STEELSERIES_MSI_KLC   0x1122
 #define USB_DEVICE_ID_STEELSERIES_MSI_ALC   0x1161
+#define USB_DEVICE_ID_STEELSERIES_RIVAL_3_WIRELESS	0x1830
 
 #define USB_VENDOR_ID_SUN		0x0430
 #define USB_DEVICE_ID_RARITAN_KVM_DONGLE	0xcdab
diff --git a/drivers/hid/hid-steelseries.c b/drivers/hid/hid-steelseries.c
index 7292da031..9fa70d21f 100644
--- a/drivers/hid/hid-steelseries.c
+++ b/drivers/hid/hid-steelseries.c
@@ -8,19 +8,25 @@
 /*
  */
 
+#include <linux/completion.h>
 #include <linux/device.h>
 #include <linux/dmi.h>
 #include <linux/hid.h>
 #include <linux/module.h>
+#include <linux/power_supply.h>
 #include <linux/usb.h>
 #include <linux/leds.h>
 #include <linux/led-class-multicolor.h>
 #include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
 
 #include "hid-ids.h"
 
 #define STEELSERIES_SRWS1		BIT(0)
 #define STEELSERIES_MSI_RGB		BIT(1)
+#define STEELSERIES_RIVAL3_WIRELESS	BIT(2)
 
 #define STEELSERIES_MSI_RGB_WVALUE 0x0300 /* Feature report, ID 0 */
 #define STEELSERIES_MSI_RGB_REPORT_LEN 524
@@ -42,6 +48,18 @@ struct steelseries_device {
 	struct mutex rgb_lock; /* protects rgb_buf */
 	u8 *rgb_buf;
 #endif
+
+	/* Rival 3 Wireless battery, on the vendor interface only */
+	bool battery_iface;
+	struct power_supply *battery;
+	struct power_supply_desc battery_desc;
+	struct delayed_work battery_work;
+	struct completion battery_reply;
+	spinlock_t battery_lock; /* protects the fields below */
+	bool battery_awaiting_reply;
+	bool battery_online;
+	bool battery_charging;
+	u8 battery_capacity;
 };
 
 #if IS_BUILTIN(CONFIG_LEDS_CLASS) || \
@@ -564,6 +582,206 @@ static int steelseries_msi_rgb_register(struct steelseries_device *sd)
 }
 #endif
 
+/*
+ * Rival 3 Wireless (2.4 GHz receiver): the battery level is read with an
+ * output report AA 01 on the vendor interface. The mouse answers through
+ * the receiver about 80 ms later with an input report whose first byte is
+ * the level in percent and whose third byte is the charging flag. There is
+ * no command echo, so a reply is only accepted while one is awaited. While
+ * the mouse is off or asleep, the receiver does not answer at all.
+ */
+#define STEELSERIES_RIVAL3_WIRELESS_IFACE		3
+#define STEELSERIES_RIVAL3_WIRELESS_REPLY_TIMEOUT_MS	500
+#define STEELSERIES_RIVAL3_WIRELESS_POLL_ONLINE_MS	(10 * 60 * 1000)
+#define STEELSERIES_RIVAL3_WIRELESS_POLL_OFFLINE_MS	(60 * 1000)
+
+static bool steelseries_rival3_is_battery_iface(struct hid_device *hdev)
+{
+	struct usb_interface *intf = steelseries_hid_to_usb_intf(hdev);
+
+	return intf && intf->cur_altsetting->desc.bInterfaceNumber ==
+		STEELSERIES_RIVAL3_WIRELESS_IFACE;
+}
+
+static const enum power_supply_property steelseries_rival3_battery_props[] = {
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_SCOPE,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_MODEL_NAME,
+	POWER_SUPPLY_PROP_MANUFACTURER,
+};
+
+static int steelseries_rival3_battery_get_property(struct power_supply *psy,
+						   enum power_supply_property psp,
+						   union power_supply_propval *val)
+{
+	struct steelseries_device *sd = power_supply_get_drvdata(psy);
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&sd->battery_lock, flags);
+	switch (psp) {
+	case POWER_SUPPLY_PROP_PRESENT:
+		val->intval = 1;
+		break;
+	case POWER_SUPPLY_PROP_STATUS:
+		if (!sd->battery_online)
+			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
+		else if (sd->battery_charging)
+			val->intval = POWER_SUPPLY_STATUS_CHARGING;
+		else
+			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
+		break;
+	case POWER_SUPPLY_PROP_SCOPE:
+		val->intval = POWER_SUPPLY_SCOPE_DEVICE;
+		break;
+	case POWER_SUPPLY_PROP_CAPACITY:
+		val->intval = sd->battery_capacity;
+		break;
+	case POWER_SUPPLY_PROP_MODEL_NAME:
+		val->strval = "Rival 3 Wireless";
+		break;
+	case POWER_SUPPLY_PROP_MANUFACTURER:
+		val->strval = "SteelSeries";
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	spin_unlock_irqrestore(&sd->battery_lock, flags);
+
+	return ret;
+}
+
+static void steelseries_rival3_battery_work(struct work_struct *work)
+{
+	struct steelseries_device *sd = container_of(work,
+			struct steelseries_device, battery_work.work);
+	static const u8 request[] = { 0x00, 0xaa, 0x01 }; /* report ID 0 */
+	bool was_online, was_charging, online, changed;
+	unsigned long flags, timeout;
+	u8 old_capacity;
+	u8 *buf;
+	int ret;
+
+	spin_lock_irqsave(&sd->battery_lock, flags);
+	was_online = sd->battery_online;
+	was_charging = sd->battery_charging;
+	old_capacity = sd->battery_capacity;
+	spin_unlock_irqrestore(&sd->battery_lock, flags);
+
+	buf = kmemdup(request, sizeof(request), GFP_KERNEL);
+	if (!buf) {
+		ret = -ENOMEM;
+		goto update;
+	}
+
+	spin_lock_irqsave(&sd->battery_lock, flags);
+	reinit_completion(&sd->battery_reply);
+	sd->battery_awaiting_reply = true;
+	spin_unlock_irqrestore(&sd->battery_lock, flags);
+
+	ret = hid_hw_raw_request(sd->hdev, 0x00, buf, sizeof(request),
+				 HID_OUTPUT_REPORT, HID_REQ_SET_REPORT);
+	kfree(buf);
+	if (ret >= 0) {
+		timeout = msecs_to_jiffies(STEELSERIES_RIVAL3_WIRELESS_REPLY_TIMEOUT_MS);
+		ret = wait_for_completion_timeout(&sd->battery_reply, timeout) ? 0 : -ETIMEDOUT;
+	}
+
+update:
+	spin_lock_irqsave(&sd->battery_lock, flags);
+	/* A reply may still have arrived right after the timeout. */
+	if (ret && sd->battery_awaiting_reply) {
+		/* Keep the last level; the mouse is off or asleep. */
+		sd->battery_awaiting_reply = false;
+		sd->battery_online = false;
+	} else {
+		ret = 0;
+	}
+	online = sd->battery_online;
+	changed = online != was_online ||
+		  sd->battery_charging != was_charging ||
+		  sd->battery_capacity != old_capacity;
+	spin_unlock_irqrestore(&sd->battery_lock, flags);
+
+	if (ret)
+		hid_dbg(sd->hdev, "No battery reply: %d\n", ret);
+	if (changed)
+		power_supply_changed(sd->battery);
+
+	schedule_delayed_work(&sd->battery_work, msecs_to_jiffies(online ?
+			STEELSERIES_RIVAL3_WIRELESS_POLL_ONLINE_MS :
+			STEELSERIES_RIVAL3_WIRELESS_POLL_OFFLINE_MS));
+}
+
+static int steelseries_rival3_battery_register(struct steelseries_device *sd)
+{
+	struct power_supply_config battery_cfg = { .drv_data = sd, };
+	struct hid_device *hdev = sd->hdev;
+	struct power_supply *battery;
+
+	spin_lock_init(&sd->battery_lock);
+	init_completion(&sd->battery_reply);
+	INIT_DELAYED_WORK(&sd->battery_work, steelseries_rival3_battery_work);
+	/* Avoid a 0% warning before the first reply; status stays unknown. */
+	sd->battery_capacity = 100;
+
+	sd->battery_desc.type = POWER_SUPPLY_TYPE_BATTERY;
+	sd->battery_desc.properties = steelseries_rival3_battery_props;
+	sd->battery_desc.num_properties = ARRAY_SIZE(steelseries_rival3_battery_props);
+	sd->battery_desc.get_property = steelseries_rival3_battery_get_property;
+	sd->battery_desc.name = devm_kasprintf(&hdev->dev, GFP_KERNEL,
+					       "steelseries_mouse_battery_%s",
+					       hdev->uniq[0] ? hdev->uniq :
+					       dev_name(&hdev->dev));
+	if (!sd->battery_desc.name)
+		return -ENOMEM;
+
+	battery = devm_power_supply_register(&hdev->dev, &sd->battery_desc,
+					     &battery_cfg);
+	if (IS_ERR(battery))
+		return PTR_ERR(battery);
+
+	power_supply_powers(battery, &hdev->dev);
+	sd->battery = battery;
+	sd->battery_iface = true;
+
+	return 0;
+}
+
+static int steelseries_raw_event(struct hid_device *hdev,
+				 struct hid_report *report, u8 *data, int size)
+{
+	struct steelseries_device *sd;
+	unsigned long flags;
+
+	if (hdev->product != USB_DEVICE_ID_STEELSERIES_RIVAL_3_WIRELESS)
+		return 0;
+
+	sd = hid_get_drvdata(hdev);
+	if (!sd || !sd->battery_iface)
+		return 0;
+
+	/* level, 0, charging, then zero padding */
+	if (size < 3 || data[0] > 100 || data[1] ||
+	    memchr_inv(data + 3, 0, size - 3))
+		return 0;
+
+	spin_lock_irqsave(&sd->battery_lock, flags);
+	if (sd->battery_awaiting_reply) {
+		sd->battery_capacity = data[0];
+		sd->battery_charging = data[2];
+		sd->battery_online = true;
+		sd->battery_awaiting_reply = false;
+		complete(&sd->battery_reply);
+	}
+	spin_unlock_irqrestore(&sd->battery_lock, flags);
+
+	return 0;
+}
+
 static int steelseries_probe(struct hid_device *hdev, const struct hid_device_id *id)
 {
 	struct steelseries_device *sd;
@@ -593,17 +811,38 @@ static int steelseries_probe(struct hid_device *hdev, const struct hid_device_id
 		}
 	}
 
+	if (sd->quirks & STEELSERIES_RIVAL3_WIRELESS &&
+	    !steelseries_rival3_is_battery_iface(hdev))
+		sd->quirks &= ~STEELSERIES_RIVAL3_WIRELESS;
+
 	ret = hid_parse(hdev);
 	if (ret)
 		return ret;
 
+	if (sd->quirks & STEELSERIES_RIVAL3_WIRELESS) {
+		ret = steelseries_rival3_battery_register(sd);
+		if (ret) {
+			hid_warn(hdev,
+				 "Failed to register battery: %d, continuing without battery reporting\n",
+				 ret);
+			sd->quirks &= ~STEELSERIES_RIVAL3_WIRELESS;
+		}
+	}
+
 	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
 	if (ret)
 		return ret;
 
-	ret = hid_hw_open(hdev);
-	if (ret)
-		goto err_stop;
+	/* Only the Rival 3 Wireless battery interface needs to stay open. */
+	if (hdev->product != USB_DEVICE_ID_STEELSERIES_RIVAL_3_WIRELESS ||
+	    sd->battery_iface) {
+		ret = hid_hw_open(hdev);
+		if (ret)
+			goto err_stop;
+	}
+
+	if (sd->battery_iface)
+		schedule_delayed_work(&sd->battery_work, msecs_to_jiffies(1000));
 
 	if (sd->quirks & STEELSERIES_MSI_RGB) {
 		ret = steelseries_msi_rgb_register(sd);
@@ -624,6 +863,8 @@ static int steelseries_probe(struct hid_device *hdev, const struct hid_device_id
 
 static void steelseries_remove(struct hid_device *hdev)
 {
+	struct steelseries_device *sd;
+
 	if (hdev->product == USB_DEVICE_ID_STEELSERIES_SRWS1) {
 #if IS_BUILTIN(CONFIG_LEDS_CLASS) || \
     (IS_MODULE(CONFIG_LEDS_CLASS) && IS_MODULE(CONFIG_HID_STEELSERIES))
@@ -632,10 +873,32 @@ static void steelseries_remove(struct hid_device *hdev)
 		return;
 	}
 
-	hid_hw_close(hdev);
+	sd = hid_get_drvdata(hdev);
+	if (sd->battery_iface)
+		cancel_delayed_work_sync(&sd->battery_work);
+
+	if (hdev->product != USB_DEVICE_ID_STEELSERIES_RIVAL_3_WIRELESS ||
+	    sd->battery_iface)
+		hid_hw_close(hdev);
 	hid_hw_stop(hdev);
 }
 
+static int steelseries_resume(struct hid_device *hdev)
+{
+	struct steelseries_device *sd;
+
+	if (hdev->product != USB_DEVICE_ID_STEELSERIES_RIVAL_3_WIRELESS)
+		return 0;
+
+	/* Polls during suspend fail, so do not wait for the next one. */
+	sd = hid_get_drvdata(hdev);
+	if (sd && sd->battery_iface)
+		mod_delayed_work(system_wq, &sd->battery_work,
+				 msecs_to_jiffies(1000));
+
+	return 0;
+}
+
 static const __u8 *steelseries_srws1_report_fixup(struct hid_device *hdev,
 		__u8 *rdesc, unsigned int *rsize)
 {
@@ -656,6 +919,9 @@ static const struct hid_device_id steelseries_devices[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_STEELSERIES, USB_DEVICE_ID_STEELSERIES_SRWS1),
 	  .driver_data = STEELSERIES_SRWS1 },
 
+	{ HID_USB_DEVICE(USB_VENDOR_ID_STEELSERIES, USB_DEVICE_ID_STEELSERIES_RIVAL_3_WIRELESS),
+	  .driver_data = STEELSERIES_RIVAL3_WIRELESS },
+
 #if STEELSERIES_HAS_LEDS_MULTICOLOR
 	{ /* MSI Raider A18 KLC */
 	  HID_USB_DEVICE(USB_VENDOR_ID_STEELSERIES, USB_DEVICE_ID_STEELSERIES_MSI_KLC),
@@ -675,6 +941,9 @@ static struct hid_driver steelseries_driver = {
 	.id_table = steelseries_devices,
 	.probe = steelseries_probe,
 	.remove = steelseries_remove,
+	.raw_event = steelseries_raw_event,
+	.resume = pm_ptr(steelseries_resume),
+	.reset_resume = pm_ptr(steelseries_resume),
 	.report_fixup = steelseries_srws1_report_fixup,
 };
 

-- 
2.56.0

Re: [PATCH 2/2] HID: steelseries: Add Rival 3 Wireless battery reporting

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 4 potential issue(s) to consider:
- [High] HID: steelseries: missing suspend and runtime PM handling for battery_work
- [High] HID: steelseries: UAF on probe failure after steelseries_resume() arms work
- [High] HID: steelseries: race between steelseries_remove() and steelseries_resume()
- [Medium] HID: steelseries: deprecated system_wq mismatch in steelseries_resume()
--

commit bd1d30fd1ed7cb8e4a6c8b3c38fe5d24efafb14d
Author: Martin Oberleiter <martin.oberleiter@netixx.it>

HID: steelseries: Add Rival 3 Wireless battery reporting

This commit adds power_supply battery reporting for the SteelSeries Rival 3
Wireless mouse in 2.4 GHz receiver mode by polling vendor interface 3 via a
delayed work item and parsing the asynchronous input report replies.

> diff --git a/drivers/hid/hid-steelseries.c b/drivers/hid/hid-steelseries.c
> index 7292da0313e11..9fa70d21f49de 100644
> --- a/drivers/hid/hid-steelseries.c
> +++ b/drivers/hid/hid-steelseries.c
[ ... ]
> +static void steelseries_rival3_battery_work(struct work_struct *work)
> +{
> +	struct steelseries_device *sd = container_of(work,
> +			struct steelseries_device, battery_work.work);
> +	static const u8 request[] = { 0x00, 0xaa, 0x01 }; /* report ID 0 */
> +	bool was_online, was_charging, online, changed;
> +	unsigned long flags, timeout;
> +	u8 old_capacity;
> +	u8 *buf;
> +	int ret;
> +
> +	spin_lock_irqsave(&sd->battery_lock, flags);
> +	was_online = sd->battery_online;
> +	was_charging = sd->battery_charging;
> +	old_capacity = sd->battery_capacity;
> +	spin_unlock_irqrestore(&sd->battery_lock, flags);
> +
> +	buf = kmemdup(request, sizeof(request), GFP_KERNEL);
> +	if (!buf) {
> +		ret = -ENOMEM;
> +		goto update;
> +	}
> +
> +	spin_lock_irqsave(&sd->battery_lock, flags);
> +	reinit_completion(&sd->battery_reply);
> +	sd->battery_awaiting_reply = true;
> +	spin_unlock_irqrestore(&sd->battery_lock, flags);
> +
> +	ret = hid_hw_raw_request(sd->hdev, 0x00, buf, sizeof(request),
> +				 HID_OUTPUT_REPORT, HID_REQ_SET_REPORT);
> +	kfree(buf);
> +	if (ret >= 0) {
> +		timeout = msecs_to_jiffies(STEELSERIES_RIVAL3_WIRELESS_REPLY_TIMEOUT_MS);
> +		ret = wait_for_completion_timeout(&sd->battery_reply, timeout) ? 0 : -ETIMEDOUT;
> +	}
> +
> +update:
> +	spin_lock_irqsave(&sd->battery_lock, flags);
> +	/* A reply may still have arrived right after the timeout. */
> +	if (ret && sd->battery_awaiting_reply) {
> +		/* Keep the last level; the mouse is off or asleep. */
> +		sd->battery_awaiting_reply = false;
> +		sd->battery_online = false;
> +	} else {
> +		ret = 0;
> +	}
> +	online = sd->battery_online;
> +	changed = online != was_online ||
> +		  sd->battery_charging != was_charging ||
> +		  sd->battery_capacity != old_capacity;
> +	spin_unlock_irqrestore(&sd->battery_lock, flags);
> +
> +	if (ret)
> +		hid_dbg(sd->hdev, "No battery reply: %d\n", ret);
> +	if (changed)
> +		power_supply_changed(sd->battery);

[Severity: High]
What happens when steelseries_rival3_battery_work() in
drivers/hid/hid-steelseries.c runs during system suspend, suspend-to-idle
(s2idle), or USB runtime autosuspend?

Because steelseries_driver registers .resume and .reset_resume callbacks
without a matching .suspend callback and queues sd->battery_work on a
non-freezable workqueue, steelseries_rival3_battery_work() can fire after
usbhid's hid_suspend() has stopped I/O and usb_suspend() has cleared
udev->can_submit (or while the system is in s2idle).

When hid_hw_raw_request() fails with -EHOSTUNREACH (or
wait_for_completion_timeout() times out with -ETIMEDOUT),
steelseries_rival3_battery_work() sets sd->battery_online = false. If the
mouse was previously online (was_online == true), changed becomes true and
power_supply_changed(sd->battery) is called:

    steelseries_rival3_battery_work()
      power_supply_changed(sd->battery)
        pm_stay_awake(&psy->dev)

Because battery_cfg.no_wakeup_source is left false in
steelseries_rival3_battery_register(), __power_supply_register() initializes
sd->battery->dev as a wakeup source, so pm_stay_awake() will abort system
suspend or wake the system from s2idle while also dropping the poll interval
to 1 minute.

In addition, usbhid enables USB runtime autosuspend and usbhid_open() drops
its usb_autopm reference before returning. Unlike
steelseries_msi_rgb_set_blocking() in the same file,
steelseries_rival3_battery_work() does not wrap the transfer and reply wait
with hid_hw_power(sd->hdev, PM_HINT_FULLON) and hid_hw_power(sd->hdev,
PM_HINT_NORMAL). Consequently, polls while the receiver is runtime-suspended
fail without waking the interface, and every runtime autoresume invokes
hid_resume() -> steelseries_resume(), resetting the 10-minute poll timer to
1 second.

Should steelseries_driver provide a .suspend callback that cancels
sd->battery_work, and should steelseries_rival3_battery_work() hold
hid_hw_power(sd->hdev, PM_HINT_FULLON) across the request and completion
wait?

> +
> +	schedule_delayed_work(&sd->battery_work, msecs_to_jiffies(online ?
> +			STEELSERIES_RIVAL3_WIRELESS_POLL_ONLINE_MS :
> +			STEELSERIES_RIVAL3_WIRELESS_POLL_OFFLINE_MS));
> +}
> +
> +static int steelseries_rival3_battery_register(struct steelseries_device *sd)
> +{
[ ... ]
> +	power_supply_powers(battery, &hdev->dev);
> +	sd->battery = battery;
> +	sd->battery_iface = true;
> +
> +	return 0;
> +}
[ ... ]
> @@ -593,17 +811,38 @@ static int steelseries_probe(struct hid_device *hdev, const struct hid_device_id
>  		}
>  	}
>  
> +	if (sd->quirks & STEELSERIES_RIVAL3_WIRELESS &&
> +	    !steelseries_rival3_is_battery_iface(hdev))
> +		sd->quirks &= ~STEELSERIES_RIVAL3_WIRELESS;
> +
>  	ret = hid_parse(hdev);
>  	if (ret)
>  		return ret;
>  
> +	if (sd->quirks & STEELSERIES_RIVAL3_WIRELESS) {
> +		ret = steelseries_rival3_battery_register(sd);
> +		if (ret) {
> +			hid_warn(hdev,
> +				 "Failed to register battery: %d, continuing without battery reporting\n",
> +				 ret);
> +			sd->quirks &= ~STEELSERIES_RIVAL3_WIRELESS;
> +		}
> +	}
> +
>  	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
>  	if (ret)
>  		return ret;
>  
> -	ret = hid_hw_open(hdev);
> -	if (ret)
> -		goto err_stop;
> +	/* Only the Rival 3 Wireless battery interface needs to stay open. */
> +	if (hdev->product != USB_DEVICE_ID_STEELSERIES_RIVAL_3_WIRELESS ||
> +	    sd->battery_iface) {
> +		ret = hid_hw_open(hdev);
> +		if (ret)
> +			goto err_stop;
> +	}

[Severity: High]
Can a failed probe in steelseries_probe() in drivers/hid/hid-steelseries.c
leave sd->battery_work armed after devres frees sd?

In __hid_device_probe(), hdev->driver is set to &steelseries_driver before
steelseries_probe() runs. In steelseries_probe(),
steelseries_rival3_battery_register() sets sd->battery_iface = true before
hid_hw_start() and hid_hw_open() are called.

If the parent usb_interface is runtime-suspended when hid_hw_open() is
called, usbhid_open() calls usb_autopm_get_interface(usbhid->intf), which
synchronously runs:

    usbhid_open()
      usb_autopm_get_interface()
        hid_resume()
          hid_driver_resume()
            steelseries_resume()
              mod_delayed_work(system_wq, &sd->battery_work, ...)

Because sd->battery_iface is already true, steelseries_resume() arms
sd->battery_work. If hid_hw_open() then fails (for example, when
hid_start_in() fails and usbhid_open() returns -EBUSY), steelseries_probe()
jumps to err_stop and returns without cancelling sd->battery_work, after
which __hid_device_probe() frees sd via devres_release_group() while the
delayed work timer is still pending.

Would it be safer to register the battery and set sd->battery_iface = true
only after hid_hw_start() and hid_hw_open() have succeeded (or cancel
sd->battery_work in the error path)?

[ ... ]
> @@ -632,10 +873,32 @@ static void steelseries_remove(struct hid_device *hdev)
>  		return;
>  	}
>  
> -	hid_hw_close(hdev);
> +	sd = hid_get_drvdata(hdev);
> +	if (sd->battery_iface)
> +		cancel_delayed_work_sync(&sd->battery_work);
> +
> +	if (hdev->product != USB_DEVICE_ID_STEELSERIES_RIVAL_3_WIRELESS ||
> +	    sd->battery_iface)
> +		hid_hw_close(hdev);
>  	hid_hw_stop(hdev);
>  }

[Severity: High]
Could steelseries_resume() race with steelseries_remove() in
drivers/hid/hid-steelseries.c and re-queue sd->battery_work during driver
unbind?

In hid_device_remove(), hdrv->remove(hdev) is called first, followed by
devres_release_group(&hdev->dev, hdev->devres_group_id), and hdev->driver is
only set to NULL afterwards. Meanwhile, usbhid's hid_resume() and
hid_reset_resume() invoke steelseries_resume() on the parent usb_interface
without holding device_lock(&hdev->dev) or hdev->driver_input_lock.

Because steelseries_remove() calls cancel_delayed_work_sync() rather than
disable_delayed_work_sync() and leaves sd->battery_iface true while
hid_hw_close(), hid_hw_stop(), and devres_release_group() execute, a
concurrent runtime resume or reset_resume on the USB interface can see
sd && sd->battery_iface and call mod_delayed_work() after
cancel_delayed_work_sync() has already returned, re-arming sd->battery_work
on memory that devres_release_group() is freeing.

Should steelseries_remove() use disable_delayed_work_sync(&sd->battery_work)
to prevent sd->battery_work from being re-queued once teardown begins?

>  
> +static int steelseries_resume(struct hid_device *hdev)
> +{
> +	struct steelseries_device *sd;
> +
> +	if (hdev->product != USB_DEVICE_ID_STEELSERIES_RIVAL_3_WIRELESS)
> +		return 0;
> +
> +	/* Polls during suspend fail, so do not wait for the next one. */
> +	sd = hid_get_drvdata(hdev);
> +	if (sd && sd->battery_iface)
> +		mod_delayed_work(system_wq, &sd->battery_work,
> +				 msecs_to_jiffies(1000));

[Severity: Medium]
In steelseries_resume() in drivers/hid/hid-steelseries.c, mod_delayed_work()
queues sd->battery_work onto system_wq, whereas steelseries_probe() and
steelseries_rival3_battery_work() use schedule_delayed_work(), which queues
onto system_percpu_wq.

In kernel/workqueue.c, system_wq and system_percpu_wq are separate
workqueue_struct instances, and system_wq is marked with __WQ_DEPRECATED,
causing __queue_work() to emit a runtime deprecation warning when the timer
expires:

    workqueue: work func steelseries_rival3_battery_work enqueued on deprecated workqueue. Use system_{percpu|dfl}_wq instead.

Mixing two different workqueue_struct instances for the same delayed_work
also bypasses __queue_work()'s single-workqueue non-reentrancy check
(worker->current_pwq->wq == wq), allowing steelseries_rival3_battery_work()
to execute concurrently on two CPUs and race on
reinit_completion(&sd->battery_reply) and sd->battery_awaiting_reply.

Should steelseries_resume() pass system_percpu_wq to mod_delayed_work() so
all scheduling of sd->battery_work uses the same non-deprecated workqueue?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261030-rival3-battery-v1-0-6b1feeaf1f52@netixx.it?part=2