Commit a98e892c authored by Werner Sembach's avatar Werner Sembach Committed by Benjamin Tissoires
Browse files

HID: core: Add functions for HID drivers to react on first open and last close call 



Adds a new function to the hid_driver struct that is called when the
userspace starts using the device, and another one that is called when
userspace stop using the device. With this a hid driver can implement
special suspend handling for devices currently not in use.

Signed-off-by: default avatarWerner Sembach <wse@tuxedocomputers.com>
Link: https://patch.msgid.link/20250211133950.422232-1-wse@tuxedocomputers.com


Signed-off-by: default avatarBenjamin Tissoires <bentiss@kernel.org>
parent a0580023

drivers/hid/hid-core.c

+8 −1
Original line number Diff line number Diff line
@@ -2396,6 +2396,9 @@ int hid_hw_open(struct hid_device *hdev) 
		ret = hdev->ll_driver->open(hdev);

		if (ret)

			hdev->ll_open_count--;



		if (hdev->driver->on_hid_hw_open)

			hdev->driver->on_hid_hw_open(hdev);

	}



	mutex_unlock(&hdev->ll_open_lock);
@@ -2415,8 +2418,12 @@ EXPORT_SYMBOL_GPL(hid_hw_open); 
void hid_hw_close(struct hid_device *hdev)

{

	mutex_lock(&hdev->ll_open_lock);

	if (!--hdev->ll_open_count)

	if (!--hdev->ll_open_count) {

		hdev->ll_driver->close(hdev);



		if (hdev->driver->on_hid_hw_close)

			hdev->driver->on_hid_hw_close(hdev);

	}

	mutex_unlock(&hdev->ll_open_lock);

}

EXPORT_SYMBOL_GPL(hid_hw_close);

include/linux/hid.h

+4 −0
Original line number Diff line number Diff line
@@ -795,6 +795,8 @@ struct hid_usage_id { 
 * @suspend: invoked on suspend (NULL means nop)

 * @resume: invoked on resume if device was not reset (NULL means nop)

 * @reset_resume: invoked on resume if device was reset (NULL means nop)

 * @on_hid_hw_open: invoked when hid core opens first instance (NULL means nop)

 * @on_hid_hw_close: invoked when hid core closes last instance (NULL means nop)

 *

 * probe should return -errno on error, or 0 on success. During probe,

 * input will not be passed to raw_event unless hid_device_io_start is
@@ -850,6 +852,8 @@ struct hid_driver { 
	int (*suspend)(struct hid_device *hdev, pm_message_t message);

	int (*resume)(struct hid_device *hdev);

	int (*reset_resume)(struct hid_device *hdev);

	void (*on_hid_hw_open)(struct hid_device *hdev);

	void (*on_hid_hw_close)(struct hid_device *hdev);



/* private: */

	struct device_driver driver;