1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 *  HID driver for gaming keys on Razer Blackwidow gaming keyboards
  4 *  Macro Key Keycodes: M1 = 191, M2 = 192, M3 = 193, M4 = 194, M5 = 195
  5 *
  6 *  Copyright (c) 2021 Jelle van der Waa <jvanderwaa@redhat.com>
  7 */
  8
  9#include <linux/device.h>
 10#include <linux/hid.h>
 11#include <linux/module.h>
 12#include <linux/random.h>
 13#include <linux/sched.h>
 14#include <linux/usb.h>
 15#include <linux/wait.h>
 16
 17#include "hid-ids.h"
 18
 19#define map_key_clear(c) hid_map_usage_clear(hi, usage, bit, max, EV_KEY, (c))
 20
 21#define RAZER_BLACKWIDOW_TRANSFER_BUF_SIZE	91
 22
 23static bool macro_key_remapping = 1;
 24module_param(macro_key_remapping, bool, 0644);
 25MODULE_PARM_DESC(macro_key_remapping, " on (Y) off (N)");
 26
 27
 28static unsigned char blackwidow_init[RAZER_BLACKWIDOW_TRANSFER_BUF_SIZE] = {
 29	0x00,
 30	0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x04,
 31	0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 32	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 33	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 34	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 35	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 36	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 37	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 38	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 39	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 40	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 41	0x04, 0x00
 42};
 43
 44static int razer_input_mapping(struct hid_device *hdev,
 45		struct hid_input *hi, struct hid_field *field,
 46		struct hid_usage *usage, unsigned long **bit, int *max)
 47{
 48
 49	if (!macro_key_remapping)
 50		return 0;
 51
 52	if ((usage->hid & HID_UP_KEYBOARD) != HID_UP_KEYBOARD)
 53		return 0;
 54
 55	switch (usage->hid & ~HID_UP_KEYBOARD) {
 56	case 0x68:
 57		map_key_clear(KEY_MACRO1);
 58		return 1;
 59	case 0x69:
 60		map_key_clear(KEY_MACRO2);
 61		return 1;
 62	case 0x6a:
 63		map_key_clear(KEY_MACRO3);
 64		return 1;
 65	case 0x6b:
 66		map_key_clear(KEY_MACRO4);
 67		return 1;
 68	case 0x6c:
 69		map_key_clear(KEY_MACRO5);
 70		return 1;
 71	}
 72
 73	return 0;
 74}
 75
 76static int razer_probe(struct hid_device *hdev, const struct hid_device_id *id)
 77{
 78	char *buf;
 79	int ret = 0;
 80
 81	ret = hid_parse(hdev);
 82	if (ret)
 83		return ret;
 84
 85	/*
 86	 * Only send the enable macro keys command for the third device
 87	 * identified as mouse input.
 88	 */
 89	if (hdev->type == HID_TYPE_USBMOUSE) {
 90		buf = kmemdup(blackwidow_init, RAZER_BLACKWIDOW_TRANSFER_BUF_SIZE, GFP_KERNEL);
 91		if (buf == NULL)
 92			return -ENOMEM;
 93
 94		ret = hid_hw_raw_request(hdev, 0, buf, RAZER_BLACKWIDOW_TRANSFER_BUF_SIZE,
 95				HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
 96		if (ret != RAZER_BLACKWIDOW_TRANSFER_BUF_SIZE)
 97			hid_err(hdev, "failed to enable macro keys: %d\n", ret);
 98
 99		kfree(buf);
100	}
101
102	return hid_hw_start(hdev, HID_CONNECT_DEFAULT);
103}
104
105static const struct hid_device_id razer_devices[] = {
106	{ HID_USB_DEVICE(USB_VENDOR_ID_RAZER,
107		USB_DEVICE_ID_RAZER_BLACKWIDOW) },
108	{ HID_USB_DEVICE(USB_VENDOR_ID_RAZER,
109		USB_DEVICE_ID_RAZER_BLACKWIDOW_CLASSIC) },
110	{ HID_USB_DEVICE(USB_VENDOR_ID_RAZER,
111		USB_DEVICE_ID_RAZER_BLACKWIDOW_ULTIMATE) },
112	{ }
113};
114MODULE_DEVICE_TABLE(hid, razer_devices);
115
116static struct hid_driver razer_driver = {
117	.name = "razer",
118	.id_table = razer_devices,
119	.input_mapping = razer_input_mapping,
120	.probe = razer_probe,
121};
122module_hid_driver(razer_driver);
123
124MODULE_AUTHOR("Jelle van der Waa <jvanderwaa@redhat.com>");
125MODULE_LICENSE("GPL");