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
31 enum mcs_touchkey_type {
32 MCS5000_TOUCHKEY,
33 MCS5080_TOUCHKEY,
34 };
35
36 struct mcs_touchkey_chip {
37 unsigned int status_reg;
38 unsigned int pressbit;
39 unsigned int press_invert;
40 unsigned int baseval;
41 };
42
43 struct 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
mcs_touchkey_interrupt(int irq,void * dev_id)54 static 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, 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(input, EV_MSC, MSC_SCAN, data->key_val);
85 input_report_key(input, data->key_code, pressed);
86 input_sync(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
mcs_touchkey_probe(struct i2c_client * client,const struct i2c_device_id * id)95 static int mcs_touchkey_probe(struct i2c_client *client,
96 const struct i2c_device_id *id)
97 {
98 const struct mcs_platform_data *pdata;
99 struct mcs_touchkey_data *data;
100 struct input_dev *input_dev;
101 unsigned int fw_reg;
102 int fw_ver;
103 int error;
104 int i;
105
106 pdata = dev_get_platdata(&client->dev);
107 if (!pdata) {
108 dev_err(&client->dev, "no platform data defined\n");
109 return -EINVAL;
110 }
111
112 data = kzalloc(struct_size(data, keycodes, pdata->key_maxval + 1),
113 GFP_KERNEL);
114 input_dev = input_allocate_device();
115 if (!data || !input_dev) {
116 dev_err(&client->dev, "Failed to allocate memory\n");
117 error = -ENOMEM;
118 goto err_free_mem;
119 }
120
121 data->client = client;
122 data->input_dev = input_dev;
123
124 if (id->driver_data == MCS5000_TOUCHKEY) {
125 data->chip.status_reg = MCS5000_TOUCHKEY_STATUS;
126 data->chip.pressbit = MCS5000_TOUCHKEY_STATUS_PRESS;
127 data->chip.baseval = MCS5000_TOUCHKEY_BASE_VAL;
128 fw_reg = MCS5000_TOUCHKEY_FW;
129 } else {
130 data->chip.status_reg = MCS5080_TOUCHKEY_STATUS;
131 data->chip.pressbit = MCS5080_TOUCHKEY_STATUS_PRESS;
132 data->chip.press_invert = 1;
133 data->chip.baseval = MCS5080_TOUCHKEY_BASE_VAL;
134 fw_reg = MCS5080_TOUCHKEY_FW;
135 }
136
137 fw_ver = i2c_smbus_read_byte_data(client, fw_reg);
138 if (fw_ver < 0) {
139 error = fw_ver;
140 dev_err(&client->dev, "i2c read error[%d]\n", error);
141 goto err_free_mem;
142 }
143 dev_info(&client->dev, "Firmware version: %d\n", fw_ver);
144
145 input_dev->name = "MELFAS MCS Touchkey";
146 input_dev->id.bustype = BUS_I2C;
147 input_dev->dev.parent = &client->dev;
148 input_dev->evbit[0] = BIT_MASK(EV_KEY);
149 if (!pdata->no_autorepeat)
150 input_dev->evbit[0] |= BIT_MASK(EV_REP);
151 input_dev->keycode = data->keycodes;
152 input_dev->keycodesize = sizeof(data->keycodes[0]);
153 input_dev->keycodemax = pdata->key_maxval + 1;
154
155 for (i = 0; i < pdata->keymap_size; i++) {
156 unsigned int val = MCS_KEY_VAL(pdata->keymap[i]);
157 unsigned int code = MCS_KEY_CODE(pdata->keymap[i]);
158
159 data->keycodes[val] = code;
160 __set_bit(code, input_dev->keybit);
161 }
162
163 input_set_capability(input_dev, EV_MSC, MSC_SCAN);
164 input_set_drvdata(input_dev, data);
165
166 if (pdata->cfg_pin)
167 pdata->cfg_pin();
168
169 if (pdata->poweron) {
170 data->poweron = pdata->poweron;
171 data->poweron(true);
172 }
173
174 error = request_threaded_irq(client->irq, NULL, mcs_touchkey_interrupt,
175 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
176 client->dev.driver->name, data);
177 if (error) {
178 dev_err(&client->dev, "Failed to register interrupt\n");
179 goto err_free_mem;
180 }
181
182 error = input_register_device(input_dev);
183 if (error)
184 goto err_free_irq;
185
186 i2c_set_clientdata(client, data);
187 return 0;
188
189 err_free_irq:
190 free_irq(client->irq, data);
191 err_free_mem:
192 input_free_device(input_dev);
193 kfree(data);
194 return error;
195 }
196
mcs_touchkey_remove(struct i2c_client * client)197 static int mcs_touchkey_remove(struct i2c_client *client)
198 {
199 struct mcs_touchkey_data *data = i2c_get_clientdata(client);
200
201 free_irq(client->irq, data);
202 if (data->poweron)
203 data->poweron(false);
204 input_unregister_device(data->input_dev);
205 kfree(data);
206
207 return 0;
208 }
209
mcs_touchkey_shutdown(struct i2c_client * client)210 static void mcs_touchkey_shutdown(struct i2c_client *client)
211 {
212 struct mcs_touchkey_data *data = i2c_get_clientdata(client);
213
214 if (data->poweron)
215 data->poweron(false);
216 }
217
218 #ifdef CONFIG_PM_SLEEP
mcs_touchkey_suspend(struct device * dev)219 static int mcs_touchkey_suspend(struct device *dev)
220 {
221 struct mcs_touchkey_data *data = dev_get_drvdata(dev);
222 struct i2c_client *client = data->client;
223
224 /* Disable the work */
225 disable_irq(client->irq);
226
227 /* Finally turn off the power */
228 if (data->poweron)
229 data->poweron(false);
230
231 return 0;
232 }
233
mcs_touchkey_resume(struct device * dev)234 static int mcs_touchkey_resume(struct device *dev)
235 {
236 struct mcs_touchkey_data *data = dev_get_drvdata(dev);
237 struct i2c_client *client = data->client;
238
239 /* Enable the device first */
240 if (data->poweron)
241 data->poweron(true);
242
243 /* Enable irq again */
244 enable_irq(client->irq);
245
246 return 0;
247 }
248 #endif
249
250 static SIMPLE_DEV_PM_OPS(mcs_touchkey_pm_ops,
251 mcs_touchkey_suspend, mcs_touchkey_resume);
252
253 static const struct i2c_device_id mcs_touchkey_id[] = {
254 { "mcs5000_touchkey", MCS5000_TOUCHKEY },
255 { "mcs5080_touchkey", MCS5080_TOUCHKEY },
256 { }
257 };
258 MODULE_DEVICE_TABLE(i2c, mcs_touchkey_id);
259
260 static struct i2c_driver mcs_touchkey_driver = {
261 .driver = {
262 .name = "mcs_touchkey",
263 .pm = &mcs_touchkey_pm_ops,
264 },
265 .probe = mcs_touchkey_probe,
266 .remove = mcs_touchkey_remove,
267 .shutdown = mcs_touchkey_shutdown,
268 .id_table = mcs_touchkey_id,
269 };
270
271 module_i2c_driver(mcs_touchkey_driver);
272
273 /* Module information */
274 MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
275 MODULE_AUTHOR("HeungJun Kim <riverful.kim@samsung.com>");
276 MODULE_DESCRIPTION("Touchkey driver for MELFAS MCS5000/5080 controller");
277 MODULE_LICENSE("GPL");
278