Re: [PATCH v6] HID: ayaneo: Add AYANEO 3 detachable controller driver

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [Low] HID: ayaneo: spurious -ENODEV errors and traffic on LED
  unregister
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commit 503e8577930caa05e37b8ae2f759096d42ca369b
Author: Matías Martínez <hello@matias.me>

HID: ayaneo: Add AYANEO 3 detachable controller driver

This commit adds a HID driver for the AYANEO 3 detachable controller,
supporting module identification, software eject, rumble intensity,
configuration reset, and multicolor LED control on its vendor interface.

> diff --git a/drivers/hid/hid-ayaneo.c b/drivers/hid/hid-ayaneo.c
> new file mode 100644
> index 0000000000000..abb754a2a0534
> --- /dev/null
> +++ b/drivers/hid/hid-ayaneo.c

[ ... ]

> +static int ayaneo_led_set(struct led_classdev *cdev, enum led_brightness value)
> +{
> +	struct led_classdev_mc *mc = lcdev_to_mccdev(cdev);
> +	struct ayaneo *aya = container_of(mc, struct ayaneo, mcled);
> +	int ret, i;
> +
> +	ACQUIRE(mutex_intr, lock)(&aya->lock);
> +	ret = ACQUIRE_ERR(mutex_intr, &lock);
> +	if (ret)
> +		return ret;
> +
> +	led_mc_calc_color_components(mc, value);
> +	aya->brightness = min(value, U8_MAX);
> +	for (i = 0; i < ARRAY_SIZE(aya->subleds); i++)
> +		aya->rgb[i] = min(aya->subleds[i].brightness, U8_MAX);
> +
> +	ret = ayaneo_send_config(aya, 0);
> +	if (ret)
> +		hid_err(aya->hdev, "failed to update RGB config: %d\n", ret);
> +	return ret;
> +}

[ ... ]

> +static int ayaneo_register_led(struct ayaneo *aya)
> +{
> +	struct led_classdev *cdev = &aya->mcled.led_cdev;
> +	int ret, i;

[ ... ]

> +	cdev->color = LED_COLOR_ID_RGB;
> +	cdev->brightness = 0;
> +	cdev->max_brightness = U8_MAX;
> +	cdev->brightness_set_blocking = ayaneo_led_set;

[Severity: Low]
Does unregistering the LED on controller power-off or unbind log spurious
-ENODEV errors and send unwanted config traffic?

When the controller is powered off (including after an eject handshake) or
disconnected, usb_disconnect() marks the device detached before
ayaneo_remove() runs.  led_classdev_multicolor_unregister() then issues an
LED_OFF write via set_brightness_work, which fails with -ENODEV in
ayaneo_send().  Because cdev->flags does not set LED_HW_PLUGGABLE and
ayaneo_led_set() logs all errors unconditionally, both ayaneo_led_set() and
the LED core log -ENODEV errors on every disconnect.

In addition, when the driver is unbound while aya->configured is false, that
same LED_OFF write during unregister still sends a 65-byte config report to
the device, even though the driver otherwise avoids sending traffic unless
userspace has configured it.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261113232228.17553-1-hello@matias.me?part=1