Commit da12b224 authored by Hans de Goede's avatar Hans de Goede Committed by Benjamin Tissoires
Browse files

HID: logitech-dj: deal with some KVMs adding an extra interface to the usbdev 



My Aten cs1764a KVM adds an extra interface to the receiver through which
it forwards mouse events, if a separate mouse is plugged in next to the
receiver dongle. This interface is present even if no extra mouse is
plugged in.

logitech-dj trying to handle this extra interface causes mouse events send
through the extra interface to not be properly handled.

This commit fixes this by treating any extra interfaces as hid-generic
interfaces.

Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarBenjamin Tissoires <benjamin.tissoires@redhat.com>
parent aca22a35

drivers/hid/hid-logitech-dj.c

+31 −1
Original line number Diff line number Diff line
@@ -27,6 +27,7 @@ 
#include <linux/module.h>

#include <linux/kfifo.h>

#include <linux/delay.h>

#include <linux/usb.h> /* For to_usb_interface for kvm extra intf check */

#include <asm/unaligned.h>

#include "hid-ids.h"
@@ -1463,6 +1464,9 @@ static int logi_dj_raw_event(struct hid_device *hdev, 
	struct dj_receiver_dev *djrcv_dev = hid_get_drvdata(hdev);

	dbg_hid("%s, size:%d\n", __func__, size);



	if (!djrcv_dev)

		return 0;



	if (!hdev->report_enum[HID_INPUT_REPORT].numbered) {



		if (djrcv_dev->unnumbered_application == HID_GD_KEYBOARD) {
@@ -1532,6 +1536,8 @@ static int logi_dj_probe(struct hid_device *hdev, 
	struct hid_report_enum *rep_enum;

	struct hid_report *rep;

	struct dj_receiver_dev *djrcv_dev;

	struct usb_interface *intf;

	unsigned int no_dj_interfaces = 0;

	bool has_hidpp = false;

	unsigned long flags;

	int retval;
@@ -1547,6 +1553,27 @@ static int logi_dj_probe(struct hid_device *hdev, 
		return retval;

	}



	/*

	 * Some KVMs add an extra interface for e.g. mouse emulation. If we

	 * treat these as logitech-dj interfaces then this causes input events

	 * reported through this extra interface to not be reported correctly.

	 * To avoid this, we treat these as generic-hid devices.

	 */

	switch (id->driver_data) {

	case recvr_type_dj:		no_dj_interfaces = 3; break;

	case recvr_type_hidpp:		no_dj_interfaces = 2; break;

	case recvr_type_gaming_hidpp:	no_dj_interfaces = 3; break;

	case recvr_type_27mhz:		no_dj_interfaces = 2; break;

	}

	if (hid_is_using_ll_driver(hdev, &usb_hid_driver)) {

		intf = to_usb_interface(hdev->dev.parent);

		if (intf && intf->altsetting->desc.bInterfaceNumber >=

							no_dj_interfaces) {

			hdev->quirks |= HID_QUIRK_INPUT_PER_APP;

			return hid_hw_start(hdev, HID_CONNECT_DEFAULT);

		}

	}



	rep_enum = &hdev->report_enum[HID_INPUT_REPORT];



	/* no input reports, bail out */
@@ -1642,7 +1669,7 @@ static int logi_dj_reset_resume(struct hid_device *hdev) 
	int retval;

	struct dj_receiver_dev *djrcv_dev = hid_get_drvdata(hdev);



	if (djrcv_dev->hidpp != hdev)

	if (!djrcv_dev || djrcv_dev->hidpp != hdev)

		return 0;



	retval = logi_dj_recv_switch_to_dj_mode(djrcv_dev, 0);
@@ -1664,6 +1691,9 @@ static void logi_dj_remove(struct hid_device *hdev) 


	dbg_hid("%s\n", __func__);



	if (!djrcv_dev)

		return hid_hw_stop(hdev);



	/*

	 * This ensures that if the work gets requeued from another

	 * interface of the same receiver it will be a no-op.

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