1/*
  2 * HID driver for CMedia CM6533 audio jack controls
  3 *
  4 * Copyright (C) 2015 Ben Chen <ben_chen@bizlinktech.com>
  5 *
  6 * This software is licensed under the terms of the GNU General Public
  7 * License version 2, as published by the Free Software Foundation, and
  8 * may be copied, distributed, and modified under those terms.
  9 *
 10 * This program is distributed in the hope that it will be useful,
 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 13 * GNU General Public License for more details.
 14 */
 15
 16#include <linux/device.h>
 17#include <linux/hid.h>
 18#include <linux/module.h>
 19#include "hid-ids.h"
 20
 21MODULE_AUTHOR("Ben Chen");
 22MODULE_DESCRIPTION("CM6533 HID jack controls");
 23MODULE_LICENSE("GPL");
 24
 25#define CM6533_JD_TYPE_COUNT      1
 26#define CM6533_JD_RAWEV_LEN	 16
 27#define CM6533_JD_SFX_OFFSET	  8
 28
 29/*
 30*
 31*CM6533 audio jack HID raw events:
 32*
 33*Plug in:
 34*01000600 002083xx 080008c0 10000000
 35*about 3 seconds later...
 36*01000a00 002083xx 08000380 10000000
 37*01000600 002083xx 08000380 10000000
 38*
 39*Plug out:
 40*01000400 002083xx 080008c0 x0000000
 41*/
 42
 43static const u8 ji_sfx[] = { 0x08, 0x00, 0x08, 0xc0 };
 44static const u8 ji_in[]  = { 0x01, 0x00, 0x06, 0x00 };
 45static const u8 ji_out[] = { 0x01, 0x00, 0x04, 0x00 };
 46
 47static int jack_switch_types[CM6533_JD_TYPE_COUNT] = {
 48	SW_HEADPHONE_INSERT,
 49};
 50
 51struct cmhid {
 52	struct input_dev *input_dev;
 53	struct hid_device *hid;
 54	unsigned short switch_map[CM6533_JD_TYPE_COUNT];
 55};
 56
 57static void hp_ev(struct hid_device *hid, struct cmhid *cm, int value)
 58{
 59	input_report_switch(cm->input_dev, SW_HEADPHONE_INSERT, value);
 60	input_sync(cm->input_dev);
 61}
 62
 63static int cmhid_raw_event(struct hid_device *hid, struct hid_report *report,
 64	 u8 *data, int len)
 65{
 66	struct cmhid *cm = hid_get_drvdata(hid);
 67
 68	if (len != CM6533_JD_RAWEV_LEN)
 69		goto out;
 70	if (memcmp(data+CM6533_JD_SFX_OFFSET, ji_sfx, sizeof(ji_sfx)))
 71		goto out;
 72
 73	if (!memcmp(data, ji_out, sizeof(ji_out))) {
 74		hp_ev(hid, cm, 0);
 75		goto out;
 76	}
 77	if (!memcmp(data, ji_in, sizeof(ji_in))) {
 78		hp_ev(hid, cm, 1);
 79		goto out;
 80	}
 81
 82out:
 83	return 0;
 84}
 85
 86static int cmhid_input_configured(struct hid_device *hid,
 87		struct hid_input *hidinput)
 88{
 89	struct input_dev *input_dev = hidinput->input;
 90	struct cmhid *cm = hid_get_drvdata(hid);
 91	int i;
 92
 93	cm->input_dev = input_dev;
 94	memcpy(cm->switch_map, jack_switch_types, sizeof(cm->switch_map));
 95	input_dev->evbit[0] = BIT(EV_SW);
 96	for (i = 0; i < CM6533_JD_TYPE_COUNT; i++)
 97		input_set_capability(cm->input_dev,
 98				EV_SW, jack_switch_types[i]);
 99	return 0;
100}
101
102static int cmhid_input_mapping(struct hid_device *hid,
103		struct hid_input *hi, struct hid_field *field,
104		struct hid_usage *usage, unsigned long **bit, int *max)
105{
106	return -1;
107}
108
109static int cmhid_probe(struct hid_device *hid, const struct hid_device_id *id)
110{
111	int ret;
112	struct cmhid *cm;
113
114	cm = kzalloc(sizeof(struct cmhid), GFP_KERNEL);
115	if (!cm) {
116		ret = -ENOMEM;
117		goto allocfail;
118	}
119
120	cm->hid = hid;
121
122	hid->quirks |= HID_QUIRK_HIDINPUT_FORCE;
123	hid_set_drvdata(hid, cm);
124
125	ret = hid_parse(hid);
126	if (ret) {
127		hid_err(hid, "parse failed\n");
128		goto fail;
129	}
130
131	ret = hid_hw_start(hid, HID_CONNECT_DEFAULT | HID_CONNECT_HIDDEV_FORCE);
132	if (ret) {
133		hid_err(hid, "hw start failed\n");
134		goto fail;
135	}
136
137	return 0;
138fail:
139	kfree(cm);
140allocfail:
141	return ret;
142}
143
144static void cmhid_remove(struct hid_device *hid)
145{
146	struct cmhid *cm = hid_get_drvdata(hid);
147
148	hid_hw_stop(hid);
149	kfree(cm);
150}
151
152static const struct hid_device_id cmhid_devices[] = {
153	{ HID_USB_DEVICE(USB_VENDOR_ID_CMEDIA, USB_DEVICE_ID_CM6533) },
154	{ }
155};
156MODULE_DEVICE_TABLE(hid, cmhid_devices);
157
158static struct hid_driver cmhid_driver = {
159	.name = "cm6533_jd",
160	.id_table = cmhid_devices,
161	.raw_event = cmhid_raw_event,
162	.input_configured = cmhid_input_configured,
163	.probe = cmhid_probe,
164	.remove = cmhid_remove,
165	.input_mapping = cmhid_input_mapping,
166};
167module_hid_driver(cmhid_driver);
168