1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * HID driver for CMedia CM6533 audio jack controls
4 *
5 * Copyright (C) 2015 Ben Chen <ben_chen@bizlinktech.com>
6 */
7
8#include <linux/device.h>
9#include <linux/hid.h>
10#include <linux/module.h>
11#include "hid-ids.h"
12
13MODULE_AUTHOR("Ben Chen");
14MODULE_DESCRIPTION("CM6533 HID jack controls");
15MODULE_LICENSE("GPL");
16
17#define CM6533_JD_TYPE_COUNT      1
18#define CM6533_JD_RAWEV_LEN	 16
19#define CM6533_JD_SFX_OFFSET	  8
20
21/*
22*
23*CM6533 audio jack HID raw events:
24*
25*Plug in:
26*01000600 002083xx 080008c0 10000000
27*about 3 seconds later...
28*01000a00 002083xx 08000380 10000000
29*01000600 002083xx 08000380 10000000
30*
31*Plug out:
32*01000400 002083xx 080008c0 x0000000
33*/
34
35static const u8 ji_sfx[] = { 0x08, 0x00, 0x08, 0xc0 };
36static const u8 ji_in[]  = { 0x01, 0x00, 0x06, 0x00 };
37static const u8 ji_out[] = { 0x01, 0x00, 0x04, 0x00 };
38
39static int jack_switch_types[CM6533_JD_TYPE_COUNT] = {
40	SW_HEADPHONE_INSERT,
41};
42
43struct cmhid {
44	struct input_dev *input_dev;
45	struct hid_device *hid;
46	unsigned short switch_map[CM6533_JD_TYPE_COUNT];
47};
48
49static void hp_ev(struct hid_device *hid, struct cmhid *cm, int value)
50{
51	input_report_switch(cm->input_dev, SW_HEADPHONE_INSERT, value);
52	input_sync(cm->input_dev);
53}
54
55static int cmhid_raw_event(struct hid_device *hid, struct hid_report *report,
56	 u8 *data, int len)
57{
58	struct cmhid *cm = hid_get_drvdata(hid);
59
60	if (len != CM6533_JD_RAWEV_LEN)
61		goto out;
62	if (memcmp(data+CM6533_JD_SFX_OFFSET, ji_sfx, sizeof(ji_sfx)))
63		goto out;
64
65	if (!memcmp(data, ji_out, sizeof(ji_out))) {
66		hp_ev(hid, cm, 0);
67		goto out;
68	}
69	if (!memcmp(data, ji_in, sizeof(ji_in))) {
70		hp_ev(hid, cm, 1);
71		goto out;
72	}
73
74out:
75	return 0;
76}
77
78static int cmhid_input_configured(struct hid_device *hid,
79		struct hid_input *hidinput)
80{
81	struct input_dev *input_dev = hidinput->input;
82	struct cmhid *cm = hid_get_drvdata(hid);
83	int i;
84
85	cm->input_dev = input_dev;
86	memcpy(cm->switch_map, jack_switch_types, sizeof(cm->switch_map));
87	input_dev->evbit[0] = BIT(EV_SW);
88	for (i = 0; i < CM6533_JD_TYPE_COUNT; i++)
89		input_set_capability(cm->input_dev,
90				EV_SW, jack_switch_types[i]);
91	return 0;
92}
93
94static int cmhid_input_mapping(struct hid_device *hid,
95		struct hid_input *hi, struct hid_field *field,
96		struct hid_usage *usage, unsigned long **bit, int *max)
97{
98	return -1;
99}
100
101static int cmhid_probe(struct hid_device *hid, const struct hid_device_id *id)
102{
103	int ret;
104	struct cmhid *cm;
105
106	cm = kzalloc(sizeof(struct cmhid), GFP_KERNEL);
107	if (!cm) {
108		ret = -ENOMEM;
109		goto allocfail;
110	}
111
112	cm->hid = hid;
113
114	hid->quirks |= HID_QUIRK_HIDINPUT_FORCE;
115	hid_set_drvdata(hid, cm);
116
117	ret = hid_parse(hid);
118	if (ret) {
119		hid_err(hid, "parse failed\n");
120		goto fail;
121	}
122
123	ret = hid_hw_start(hid, HID_CONNECT_DEFAULT | HID_CONNECT_HIDDEV_FORCE);
124	if (ret) {
125		hid_err(hid, "hw start failed\n");
126		goto fail;
127	}
128
129	return 0;
130fail:
131	kfree(cm);
132allocfail:
133	return ret;
134}
135
136static void cmhid_remove(struct hid_device *hid)
137{
138	struct cmhid *cm = hid_get_drvdata(hid);
139
140	hid_hw_stop(hid);
141	kfree(cm);
142}
143
144static const struct hid_device_id cmhid_devices[] = {
145	{ HID_USB_DEVICE(USB_VENDOR_ID_CMEDIA, USB_DEVICE_ID_CM6533) },
146	{ }
147};
148MODULE_DEVICE_TABLE(hid, cmhid_devices);
149
150static struct hid_driver cmhid_driver = {
151	.name = "cm6533_jd",
152	.id_table = cmhid_devices,
153	.raw_event = cmhid_raw_event,
154	.input_configured = cmhid_input_configured,
155	.probe = cmhid_probe,
156	.remove = cmhid_remove,
157	.input_mapping = cmhid_input_mapping,
158};
159module_hid_driver(cmhid_driver);
160
161