1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Touchkey driver for MELFAS MCS5000/5080 controller
4 *
5 * Copyright (C) 2010 Samsung Electronics Co.Ltd
6 * Author: HeungJun Kim <riverful.kim@samsung.com>
7 * Author: Joonyoung Shim <jy0922.shim@samsung.com>
8 */
9
10#include <linux/module.h>
11#include <linux/i2c.h>
12#include <linux/interrupt.h>
13#include <linux/input.h>
14#include <linux/irq.h>
15#include <linux/slab.h>
16#include <linux/platform_data/mcs.h>
17#include <linux/pm.h>
18
19/* MCS5000 Touchkey */
20#define MCS5000_TOUCHKEY_STATUS 0x04
21#define MCS5000_TOUCHKEY_STATUS_PRESS 7
22#define MCS5000_TOUCHKEY_FW 0x0a
23#define MCS5000_TOUCHKEY_BASE_VAL 0x61
24
25/* MCS5080 Touchkey */
26#define MCS5080_TOUCHKEY_STATUS 0x00
27#define MCS5080_TOUCHKEY_STATUS_PRESS 3
28#define MCS5080_TOUCHKEY_FW 0x01
29#define MCS5080_TOUCHKEY_BASE_VAL 0x1
30
31enum mcs_touchkey_type {
32 MCS5000_TOUCHKEY,
33 MCS5080_TOUCHKEY,
34};
35
36struct mcs_touchkey_chip {
37 unsigned int status_reg;
38 unsigned int pressbit;
39 unsigned int press_invert;
40 unsigned int baseval;
41};
42
43struct mcs_touchkey_data {
44 void (*poweron)(bool);
45
46 struct i2c_client *client;
47 struct input_dev *input_dev;
48 struct mcs_touchkey_chip chip;
49 unsigned int key_code;
50 unsigned int key_val;
51 unsigned short keycodes[];
52};
53
54static irqreturn_t mcs_touchkey_interrupt(int irq, void *dev_id)
55{
56 struct mcs_touchkey_data *data = dev_id;
57 struct mcs_touchkey_chip *chip = &data->chip;
58 struct i2c_client *client = data->client;
59 struct input_dev *input = data->input_dev;
60 unsigned int key_val;
61 unsigned int pressed;
62 int val;
63
64 val = i2c_smbus_read_byte_data(client, command: chip->status_reg);
65 if (val < 0) {
66 dev_err(&client->dev, "i2c read error [%d]\n", val);
67 goto out;
68 }
69
70 pressed = (val & (1 << chip->pressbit)) >> chip->pressbit;
71 if (chip->press_invert)
72 pressed ^= chip->press_invert;
73
74 /* key_val is 0 when released, so we should use key_val of press. */
75 if (pressed) {
76 key_val = val & (0xff >> (8 - chip->pressbit));
77 if (!key_val)
78 goto out;
79 key_val -= chip->baseval;
80 data->key_code = data->keycodes[key_val];
81 data->key_val = key_val;
82 }
83
84 input_event(dev: input, EV_MSC, MSC_SCAN, value: data->key_val);
85 input_report_key(dev: input, code: data->key_code, value: pressed);
86 input_sync(dev: input);
87
88 dev_dbg(&client->dev, "key %d %d %s\n", data->key_val, data->key_code,
89 pressed ? "pressed" : "released");
90
91 out:
92 return IRQ_HANDLED;
93}
94
95static void mcs_touchkey_poweroff(void *data)
96{
97 struct mcs_touchkey_data *touchkey = data;
98
99 touchkey->poweron(false);
100}
101
102static int mcs_touchkey_probe(struct i2c_client *client)
103{
104 const struct i2c_device_id *id = i2c_client_get_device_id(client);
105 const struct mcs_platform_data *pdata;
106 struct mcs_touchkey_data *data;
107 struct input_dev *input_dev;
108 unsigned int fw_reg;
109 int fw_ver;
110 int error;
111 int i;
112
113 pdata = dev_get_platdata(dev: &client->dev);
114 if (!pdata) {
115 dev_err(&client->dev, "no platform data defined\n");
116 return -EINVAL;
117 }
118
119 data = devm_kzalloc(dev: &client->dev,
120 struct_size(data, keycodes, pdata->key_maxval + 1),
121 GFP_KERNEL);
122 if (!data)
123 return -ENOMEM;
124
125 input_dev = devm_input_allocate_device(&client->dev);
126 if (!input_dev) {
127 dev_err(&client->dev, "Failed to allocate input device\n");
128 return -ENOMEM;
129 }
130
131 data->client = client;
132 data->input_dev = input_dev;
133
134 if (id->driver_data == MCS5000_TOUCHKEY) {
135 data->chip.status_reg = MCS5000_TOUCHKEY_STATUS;
136 data->chip.pressbit = MCS5000_TOUCHKEY_STATUS_PRESS;
137 data->chip.baseval = MCS5000_TOUCHKEY_BASE_VAL;
138 fw_reg = MCS5000_TOUCHKEY_FW;
139 } else {
140 data->chip.status_reg = MCS5080_TOUCHKEY_STATUS;
141 data->chip.pressbit = MCS5080_TOUCHKEY_STATUS_PRESS;
142 data->chip.press_invert = 1;
143 data->chip.baseval = MCS5080_TOUCHKEY_BASE_VAL;
144 fw_reg = MCS5080_TOUCHKEY_FW;
145 }
146
147 fw_ver = i2c_smbus_read_byte_data(client, command: fw_reg);
148 if (fw_ver < 0) {
149 dev_err(&client->dev, "i2c read error[%d]\n", fw_ver);
150 return fw_ver;
151 }
152 dev_info(&client->dev, "Firmware version: %d\n", fw_ver);
153
154 input_dev->name = "MELFAS MCS Touchkey";
155 input_dev->id.bustype = BUS_I2C;
156 input_dev->evbit[0] = BIT_MASK(EV_KEY);
157 if (!pdata->no_autorepeat)
158 input_dev->evbit[0] |= BIT_MASK(EV_REP);
159 input_dev->keycode = data->keycodes;
160 input_dev->keycodesize = sizeof(data->keycodes[0]);
161 input_dev->keycodemax = pdata->key_maxval + 1;
162
163 for (i = 0; i < pdata->keymap_size; i++) {
164 unsigned int val = MCS_KEY_VAL(pdata->keymap[i]);
165 unsigned int code = MCS_KEY_CODE(pdata->keymap[i]);
166
167 data->keycodes[val] = code;
168 __set_bit(code, input_dev->keybit);
169 }
170
171 input_set_capability(dev: input_dev, EV_MSC, MSC_SCAN);
172 input_set_drvdata(dev: input_dev, data);
173
174 if (pdata->cfg_pin)
175 pdata->cfg_pin();
176
177 if (pdata->poweron) {
178 data->poweron = pdata->poweron;
179 data->poweron(true);
180
181 error = devm_add_action_or_reset(&client->dev,
182 mcs_touchkey_poweroff, data);
183 if (error)
184 return error;
185 }
186
187 error = devm_request_threaded_irq(dev: &client->dev, irq: client->irq,
188 NULL, thread_fn: mcs_touchkey_interrupt,
189 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
190 devname: client->dev.driver->name, dev_id: data);
191 if (error) {
192 dev_err(&client->dev, "Failed to register interrupt\n");
193 return error;
194 }
195
196 error = input_register_device(input_dev);
197 if (error)
198 return error;
199
200 i2c_set_clientdata(client, data);
201 return 0;
202}
203
204static void mcs_touchkey_shutdown(struct i2c_client *client)
205{
206 struct mcs_touchkey_data *data = i2c_get_clientdata(client);
207
208 if (data->poweron)
209 data->poweron(false);
210}
211
212static int mcs_touchkey_suspend(struct device *dev)
213{
214 struct mcs_touchkey_data *data = dev_get_drvdata(dev);
215 struct i2c_client *client = data->client;
216
217 /* Disable the work */
218 disable_irq(irq: client->irq);
219
220 /* Finally turn off the power */
221 if (data->poweron)
222 data->poweron(false);
223
224 return 0;
225}
226
227static int mcs_touchkey_resume(struct device *dev)
228{
229 struct mcs_touchkey_data *data = dev_get_drvdata(dev);
230 struct i2c_client *client = data->client;
231
232 /* Enable the device first */
233 if (data->poweron)
234 data->poweron(true);
235
236 /* Enable irq again */
237 enable_irq(irq: client->irq);
238
239 return 0;
240}
241
242static DEFINE_SIMPLE_DEV_PM_OPS(mcs_touchkey_pm_ops,
243 mcs_touchkey_suspend, mcs_touchkey_resume);
244
245static const struct i2c_device_id mcs_touchkey_id[] = {
246 { "mcs5000_touchkey", MCS5000_TOUCHKEY },
247 { "mcs5080_touchkey", MCS5080_TOUCHKEY },
248 { }
249};
250MODULE_DEVICE_TABLE(i2c, mcs_touchkey_id);
251
252static struct i2c_driver mcs_touchkey_driver = {
253 .driver = {
254 .name = "mcs_touchkey",
255 .pm = pm_sleep_ptr(&mcs_touchkey_pm_ops),
256 },
257 .probe = mcs_touchkey_probe,
258 .shutdown = mcs_touchkey_shutdown,
259 .id_table = mcs_touchkey_id,
260};
261
262module_i2c_driver(mcs_touchkey_driver);
263
264/* Module information */
265MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
266MODULE_AUTHOR("HeungJun Kim <riverful.kim@samsung.com>");
267MODULE_DESCRIPTION("Touchkey driver for MELFAS MCS5000/5080 controller");
268MODULE_LICENSE("GPL");
269

source code of linux/drivers/input/keyboard/mcs_touchkey.c