// SPDX-License-Identifier: GPL-2.0-or-later /* * HID driver for ELECOM devices: * - BM084 Bluetooth Mouse * - EX-G Trackballs (M-XT3DRBK, M-XT3URBK, M-XT4DRBK) * - DEFT Trackballs (M-DT1DRBK, M-DT1URBK, M-DT2DRBK, M-DT2URBK) * - HUGE Trackballs (M-HT1DRBK, M-HT1URBK) * * Copyright (c) 2010 Richard Nauber <Richard.Nauber@gmail.com> * Copyright (c) 2016 Yuxuan Shui <yshuiv7@gmail.com> * Copyright (c) 2017 Diego Elio Pettenò <flameeyes@flameeyes.eu> * Copyright (c) 2017 Alex Manoussakis <amanou@gnu.org> * Copyright (c) 2017 Tomasz Kramkowski <tk@the-tk.com> * Copyright (c) 2020 YOSHIOKA Takuma <lo48576@hard-wi.red> */ /* */ #include <linux/device.h> #include <linux/hid.h> #include <linux/module.h> #include "hid-ids.h" /* * Certain ELECOM mice misreport their button count meaning that they only work * correctly with the ELECOM mouse assistant software which is unavailable for * Linux. A four extra INPUT reports and a FEATURE report are described by the * report descriptor but it does not appear that these enable software to * control what the extra buttons map to. The only simple and straightforward * solution seems to involve fixing up the report descriptor. */ #define MOUSE_BUTTONS_MAX 8 static void mouse_button_fixup(struct hid_device *hdev, __u8 *rdesc, unsigned int rsize, unsigned int button_bit_count, unsigned int padding_bit, unsigned int button_report_size, unsigned int button_usage_maximum, int nbuttons) { if (rsize < 32 || rdesc[button_bit_count] != 0x95 || rdesc[button_report_size] != 0x75 || rdesc[button_report_size + 1] != 0x01 || rdesc[button_usage_maximum] != 0x29 || rdesc[padding_bit] != 0x75) return; hid_info(hdev, "Fixing up Elecom mouse button count\n"); nbuttons = clamp(nbuttons, 0, MOUSE_BUTTONS_MAX); rdesc[button_bit_count + 1] = nbuttons; rdesc[button_usage_maximum + 1] = nbuttons; rdesc[padding_bit + 1] = MOUSE_BUTTONS_MAX - nbuttons; } static __u8 *elecom_report_fixup(struct hid_device *hdev, __u8 *rdesc, unsigned int *rsize) { switch (hdev->product) { case USB_DEVICE_ID_ELECOM_BM084: /* The BM084 Bluetooth mouse includes a non-existing horizontal * wheel in the HID descriptor. */ if (*rsize >= 48 && rdesc[46] == 0x05 && rdesc[47] == 0x0c) { hid_info(hdev, "Fixing up Elecom BM084 report descriptor\n"); rdesc[47] = 0x00; } break; case USB_DEVICE_ID_ELECOM_M_XGL20DLBK: /* * Report descriptor format: * 20: button bit count * 28: padding bit count * 22: button report size * 14: button usage maximum */ mouse_button_fixup(hdev, rdesc, *rsize, 20, 28, 22, 14, 8); break; case USB_DEVICE_ID_ELECOM_M_XT3URBK: case USB_DEVICE_ID_ELECOM_M_XT3DRBK: case USB_DEVICE_ID_ELECOM_M_XT4DRBK: /* * Report descriptor format: * 12: button bit count * 30: padding bit count * 14: button report size * 20: button usage maximum */ mouse_button_fixup(hdev, rdesc, *rsize, 12, 30, 14, 20, 6); break; case USB_DEVICE_ID_ELECOM_M_DT1URBK: case USB_DEVICE_ID_ELECOM_M_DT1DRBK: case USB_DEVICE_ID_ELECOM_M_HT1URBK: case USB_DEVICE_ID_ELECOM_M_HT1DRBK: /* * Report descriptor format: * 12: button bit count * 30: padding bit count * 14: button report size * 20: button usage maximum */ mouse_button_fixup(hdev, rdesc, *rsize, 12, 30, 14, 20, 8); break; } return rdesc; } static const struct hid_device_id elecom_devices[] = { { HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_BM084) }, { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XGL20DLBK) }, { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT3URBK) }, { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT3DRBK) }, { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT4DRBK) }, { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_DT1URBK) }, { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_DT1DRBK) }, { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1URBK) }, { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1DRBK) }, { } }; MODULE_DEVICE_TABLE(hid, elecom_devices); static struct hid_driver elecom_driver = { .name = "elecom", .id_table = elecom_devices, .report_fixup = elecom_report_fixup }; module_hid_driver(elecom_driver); MODULE_LICENSE("GPL");