1/*
 2 * HID driver for primax and similar keyboards with in-band modifiers
 3 *
 4 * Copyright 2011 Google Inc. All Rights Reserved
 5 *
 6 * Author:
 7 *	Terry Lambert <tlambert@google.com>
 8 *
 9 * This software is licensed under the terms of the GNU General Public
10 * License version 2, as published by the Free Software Foundation, and
11 * may be copied, distributed, and modified under those terms.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 * GNU General Public License for more details.
17 */
18
19#include <linux/device.h>
20#include <linux/hid.h>
21#include <linux/module.h>
22
23#include "hid-ids.h"
24
25static int px_raw_event(struct hid_device *hid, struct hid_report *report,
26	 u8 *data, int size)
27{
28	int idx = size;
29
30	switch (report->id) {
31	case 0:		/* keyboard input */
32		/*
33		 * Convert in-band modifier key values into out of band
34		 * modifier bits and pull the key strokes from the report.
35		 * Thus a report data set which looked like:
36		 *
37		 * [00][00][E0][30][00][00][00][00]
38		 * (no modifier bits + "Left Shift" key + "1" key)
39		 *
40		 * Would be converted to:
41		 *
42		 * [01][00][00][30][00][00][00][00]
43		 * (Left Shift modifier bit + "1" key)
44		 *
45		 * As long as it's in the size range, the upper level
46		 * drivers don't particularly care if there are in-band
47		 * 0-valued keys, so they don't stop parsing.
48		 */
49		while (--idx > 1) {
50			if (data[idx] < 0xE0 || data[idx] > 0xE7)
51				continue;
52			data[0] |= (1 << (data[idx] - 0xE0));
53			data[idx] = 0;
54		}
55		hid_report_raw_event(hid, HID_INPUT_REPORT, data, size, 0);
56		return 1;
57
58	default:	/* unknown report */
59		/* Unknown report type; pass upstream */
60		hid_info(hid, "unknown report type %d\n", report->id);
61		break;
62	}
63
64	return 0;
65}
66
67static const struct hid_device_id px_devices[] = {
68	{ HID_USB_DEVICE(USB_VENDOR_ID_PRIMAX, USB_DEVICE_ID_PRIMAX_KEYBOARD) },
69	{ }
70};
71MODULE_DEVICE_TABLE(hid, px_devices);
72
73static struct hid_driver px_driver = {
74	.name = "primax",
75	.id_table = px_devices,
76	.raw_event = px_raw_event,
77};
78module_hid_driver(px_driver);
79
80MODULE_AUTHOR("Terry Lambert <tlambert@google.com>");
81MODULE_LICENSE("GPL");

 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * HID driver for primax and similar keyboards with in-band modifiers
 4 *
 5 * Copyright 2011 Google Inc. All Rights Reserved
 6 *
 7 * Author:
 8 *	Terry Lambert <tlambert@google.com>
 
 
 
 
 
 
 
 
 
 9 */
10
11#include <linux/device.h>
12#include <linux/hid.h>
13#include <linux/module.h>
14
15#include "hid-ids.h"
16
17static int px_raw_event(struct hid_device *hid, struct hid_report *report,
18	 u8 *data, int size)
19{
20	int idx = size;
21
22	switch (report->id) {
23	case 0:		/* keyboard input */
24		/*
25		 * Convert in-band modifier key values into out of band
26		 * modifier bits and pull the key strokes from the report.
27		 * Thus a report data set which looked like:
28		 *
29		 * [00][00][E0][30][00][00][00][00]
30		 * (no modifier bits + "Left Shift" key + "1" key)
31		 *
32		 * Would be converted to:
33		 *
34		 * [01][00][00][30][00][00][00][00]
35		 * (Left Shift modifier bit + "1" key)
36		 *
37		 * As long as it's in the size range, the upper level
38		 * drivers don't particularly care if there are in-band
39		 * 0-valued keys, so they don't stop parsing.
40		 */
41		while (--idx > 1) {
42			if (data[idx] < 0xE0 || data[idx] > 0xE7)
43				continue;
44			data[0] |= (1 << (data[idx] - 0xE0));
45			data[idx] = 0;
46		}
47		hid_report_raw_event(hid, HID_INPUT_REPORT, data, size, 0);
48		return 1;
49
50	default:	/* unknown report */
51		/* Unknown report type; pass upstream */
52		hid_info(hid, "unknown report type %d\n", report->id);
53		break;
54	}
55
56	return 0;
57}
58
59static const struct hid_device_id px_devices[] = {
60	{ HID_USB_DEVICE(USB_VENDOR_ID_PRIMAX, USB_DEVICE_ID_PRIMAX_KEYBOARD) },
61	{ }
62};
63MODULE_DEVICE_TABLE(hid, px_devices);
64
65static struct hid_driver px_driver = {
66	.name = "primax",
67	.id_table = px_devices,
68	.raw_event = px_raw_event,
69};
70module_hid_driver(px_driver);
71
72MODULE_AUTHOR("Terry Lambert <tlambert@google.com>");
73MODULE_LICENSE("GPL");