projects/linux·blob master · refs

366 lines · 9.5 KiB

1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * TM2 touchkey device driver
4 *
5 * Copyright 2005 Phil Blundell
6 * Copyright 2016 Samsung Electronics Co., Ltd.
7 *
8 * Author: Beomho Seo <[email protected]>
9 * Author: Jaechul Lee <[email protected]>
10 */
11
12#include <linux/bitops.h>
13#include <linux/delay.h>
14#include <linux/device.h>
15#include <linux/i2c.h>
16#include <linux/input.h>
17#include <linux/interrupt.h>
18#include <linux/irq.h>
19#include <linux/leds.h>
20#include <linux/module.h>
21#include <linux/of.h>
22#include <linux/pm.h>
23#include <linux/regulator/consumer.h>
24
25#define TM2_TOUCHKEY_DEV_NAME "tm2-touchkey"
26
27#define ARIES_TOUCHKEY_CMD_LED_ON 0x1
28#define ARIES_TOUCHKEY_CMD_LED_OFF 0x2
29#define TM2_TOUCHKEY_CMD_LED_ON 0x10
30#define TM2_TOUCHKEY_CMD_LED_OFF 0x20
31#define TM2_TOUCHKEY_BIT_PRESS_EV BIT(3)
32#define TM2_TOUCHKEY_BIT_KEYCODE GENMASK(2, 0)
33#define TM2_TOUCHKEY_LED_VOLTAGE_MIN 2500000
34#define TM2_TOUCHKEY_LED_VOLTAGE_MAX 3300000
35
36struct touchkey_variant {
37 u8 keycode_reg;
38 u8 base_reg;
39 u8 cmd_led_on;
40 u8 cmd_led_off;
41 bool no_reg;
42 bool fixed_regulator;
43};
44
45struct tm2_touchkey_data {
46 struct i2c_client *client;
47 struct input_dev *input_dev;
48 struct led_classdev led_dev;
49 struct regulator *vdd;
50 struct regulator_bulk_data regulators[3];
51 const struct touchkey_variant *variant;
52 u32 keycodes[4];
53 int num_keycodes;
54};
55
56static const struct touchkey_variant tm2_touchkey_variant = {
57 .keycode_reg = 0x03,
58 .base_reg = 0x00,
59 .cmd_led_on = TM2_TOUCHKEY_CMD_LED_ON,
60 .cmd_led_off = TM2_TOUCHKEY_CMD_LED_OFF,
61};
62
63static const struct touchkey_variant midas_touchkey_variant = {
64 .keycode_reg = 0x00,
65 .base_reg = 0x00,
66 .cmd_led_on = TM2_TOUCHKEY_CMD_LED_ON,
67 .cmd_led_off = TM2_TOUCHKEY_CMD_LED_OFF,
68};
69
70static struct touchkey_variant aries_touchkey_variant = {
71 .no_reg = true,
72 .fixed_regulator = true,
73 .cmd_led_on = ARIES_TOUCHKEY_CMD_LED_ON,
74 .cmd_led_off = ARIES_TOUCHKEY_CMD_LED_OFF,
75};
76
77static const struct touchkey_variant tc360_touchkey_variant = {
78 .keycode_reg = 0x00,
79 .base_reg = 0x00,
80 .fixed_regulator = true,
81 .cmd_led_on = TM2_TOUCHKEY_CMD_LED_ON,
82 .cmd_led_off = TM2_TOUCHKEY_CMD_LED_OFF,
83};
84
85static int tm2_touchkey_led_brightness_set(struct led_classdev *led_dev,
86 enum led_brightness brightness)
87{
88 struct tm2_touchkey_data *touchkey =
89 container_of(led_dev, struct tm2_touchkey_data, led_dev);
90 u32 volt;
91 u8 data;
92
93 if (brightness == LED_OFF) {
94 volt = TM2_TOUCHKEY_LED_VOLTAGE_MIN;
95 data = touchkey->variant->cmd_led_off;
96 } else {
97 volt = TM2_TOUCHKEY_LED_VOLTAGE_MAX;
98 data = touchkey->variant->cmd_led_on;
99 }
100
101 if (!touchkey->variant->fixed_regulator)
102 regulator_set_voltage(touchkey->vdd, volt, volt);
103
104 return touchkey->variant->no_reg ?
105 i2c_smbus_write_byte(touchkey->client, data) :
106 i2c_smbus_write_byte_data(touchkey->client,
107 touchkey->variant->base_reg, data);
108}
109
110static int tm2_touchkey_power_enable(struct tm2_touchkey_data *touchkey)
111{
112 int error;
113
114 error = regulator_bulk_enable(ARRAY_SIZE(touchkey->regulators),
115 touchkey->regulators);
116 if (error)
117 return error;
118
119 /* waiting for device initialization, at least 150ms */
120 msleep(150);
121
122 return 0;
123}
124
125static void tm2_touchkey_power_disable(void *data)
126{
127 struct tm2_touchkey_data *touchkey = data;
128
129 regulator_bulk_disable(ARRAY_SIZE(touchkey->regulators),
130 touchkey->regulators);
131}
132
133static irqreturn_t tm2_touchkey_irq_handler(int irq, void *devid)
134{
135 struct tm2_touchkey_data *touchkey = devid;
136 int data;
137 int index;
138 int i;
139
140 if (touchkey->variant->no_reg)
141 data = i2c_smbus_read_byte(touchkey->client);
142 else
143 data = i2c_smbus_read_byte_data(touchkey->client,
144 touchkey->variant->keycode_reg);
145 if (data < 0) {
146 dev_err(&touchkey->client->dev,
147 "failed to read i2c data: %d\n", data);
148 goto out;
149 }
150
151 index = (data & TM2_TOUCHKEY_BIT_KEYCODE) - 1;
152 if (index < 0 || index >= touchkey->num_keycodes) {
153 dev_warn(&touchkey->client->dev,
154 "invalid keycode index %d\n", index);
155 goto out;
156 }
157
158 input_event(touchkey->input_dev, EV_MSC, MSC_SCAN, index);
159
160 if (data & TM2_TOUCHKEY_BIT_PRESS_EV) {
161 for (i = 0; i < touchkey->num_keycodes; i++)
162 input_report_key(touchkey->input_dev,
163 touchkey->keycodes[i], 0);
164 } else {
165 input_report_key(touchkey->input_dev,
166 touchkey->keycodes[index], 1);
167 }
168
169 input_sync(touchkey->input_dev);
170
171out:
172 if (touchkey->variant->fixed_regulator &&
173 data & TM2_TOUCHKEY_BIT_PRESS_EV) {
174 /* touch turns backlight on, so make sure we're in sync */
175 if (touchkey->led_dev.brightness == LED_OFF)
176 tm2_touchkey_led_brightness_set(&touchkey->led_dev,
177 LED_OFF);
178 }
179
180 return IRQ_HANDLED;
181}
182
183static int tm2_touchkey_probe(struct i2c_client *client)
184{
185 struct device_node *np = client->dev.of_node;
186 struct tm2_touchkey_data *touchkey;
187 int error;
188 int i;
189
190 if (!i2c_check_functionality(client->adapter,
191 I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA)) {
192 dev_err(&client->dev, "incompatible I2C adapter\n");
193 return -EIO;
194 }
195
196 touchkey = devm_kzalloc(&client->dev, sizeof(*touchkey), GFP_KERNEL);
197 if (!touchkey)
198 return -ENOMEM;
199
200 touchkey->client = client;
201 i2c_set_clientdata(client, touchkey);
202
203 touchkey->variant = of_device_get_match_data(&client->dev);
204
205 touchkey->regulators[0].supply = "vcc";
206 touchkey->regulators[1].supply = "vdd";
207 touchkey->regulators[2].supply = "vddio";
208 error = devm_regulator_bulk_get(&client->dev,
209 ARRAY_SIZE(touchkey->regulators),
210 touchkey->regulators);
211 if (error) {
212 dev_err(&client->dev, "failed to get regulators: %d\n", error);
213 return error;
214 }
215
216 /* Save VDD for easy access */
217 touchkey->vdd = touchkey->regulators[1].consumer;
218
219 touchkey->num_keycodes = of_property_read_variable_u32_array(np,
220 "linux,keycodes", touchkey->keycodes, 0,
221 ARRAY_SIZE(touchkey->keycodes));
222 if (touchkey->num_keycodes <= 0) {
223 /* default keycodes */
224 touchkey->keycodes[0] = KEY_PHONE;
225 touchkey->keycodes[1] = KEY_BACK;
226 touchkey->num_keycodes = 2;
227 }
228
229 error = tm2_touchkey_power_enable(touchkey);
230 if (error) {
231 dev_err(&client->dev, "failed to power up device: %d\n", error);
232 return error;
233 }
234
235 error = devm_add_action_or_reset(&client->dev,
236 tm2_touchkey_power_disable, touchkey);
237 if (error) {
238 dev_err(&client->dev,
239 "failed to install poweroff handler: %d\n", error);
240 return error;
241 }
242
243 /* input device */
244 touchkey->input_dev = devm_input_allocate_device(&client->dev);
245 if (!touchkey->input_dev) {
246 dev_err(&client->dev, "failed to allocate input device\n");
247 return -ENOMEM;
248 }
249
250 touchkey->input_dev->name = TM2_TOUCHKEY_DEV_NAME;
251 touchkey->input_dev->id.bustype = BUS_I2C;
252
253 touchkey->input_dev->keycode = touchkey->keycodes;
254 touchkey->input_dev->keycodemax = touchkey->num_keycodes;
255 touchkey->input_dev->keycodesize = sizeof(touchkey->keycodes[0]);
256
257 input_set_capability(touchkey->input_dev, EV_MSC, MSC_SCAN);
258 for (i = 0; i < touchkey->num_keycodes; i++)
259 input_set_capability(touchkey->input_dev, EV_KEY,
260 touchkey->keycodes[i]);
261
262 error = input_register_device(touchkey->input_dev);
263 if (error) {
264 dev_err(&client->dev,
265 "failed to register input device: %d\n", error);
266 return error;
267 }
268
269 error = devm_request_threaded_irq(&client->dev, client->irq,
270 NULL, tm2_touchkey_irq_handler,
271 IRQF_ONESHOT,
272 TM2_TOUCHKEY_DEV_NAME, touchkey);
273 if (error) {
274 dev_err(&client->dev,
275 "failed to request threaded irq: %d\n", error);
276 return error;
277 }
278
279 /* led device */
280 touchkey->led_dev.name = TM2_TOUCHKEY_DEV_NAME;
281 touchkey->led_dev.brightness = LED_ON;
282 touchkey->led_dev.max_brightness = LED_ON;
283 touchkey->led_dev.brightness_set_blocking =
284 tm2_touchkey_led_brightness_set;
285
286 error = devm_led_classdev_register(&client->dev, &touchkey->led_dev);
287 if (error) {
288 dev_err(&client->dev,
289 "failed to register touchkey led: %d\n", error);
290 return error;
291 }
292
293 if (touchkey->variant->fixed_regulator)
294 tm2_touchkey_led_brightness_set(&touchkey->led_dev, LED_ON);
295
296 return 0;
297}
298
299static int tm2_touchkey_suspend(struct device *dev)
300{
301 struct i2c_client *client = to_i2c_client(dev);
302 struct tm2_touchkey_data *touchkey = i2c_get_clientdata(client);
303
304 disable_irq(client->irq);
305 tm2_touchkey_power_disable(touchkey);
306
307 return 0;
308}
309
310static int tm2_touchkey_resume(struct device *dev)
311{
312 struct i2c_client *client = to_i2c_client(dev);
313 struct tm2_touchkey_data *touchkey = i2c_get_clientdata(client);
314 int ret;
315
316 enable_irq(client->irq);
317
318 ret = tm2_touchkey_power_enable(touchkey);
319 if (ret)
320 dev_err(dev, "failed to enable power: %d\n", ret);
321
322 return ret;
323}
324
325static DEFINE_SIMPLE_DEV_PM_OPS(tm2_touchkey_pm_ops,
326 tm2_touchkey_suspend, tm2_touchkey_resume);
327
328static const struct i2c_device_id tm2_touchkey_id_table[] = {
329 { .name = TM2_TOUCHKEY_DEV_NAME },
330 { }
331};
332MODULE_DEVICE_TABLE(i2c, tm2_touchkey_id_table);
333
334static const struct of_device_id tm2_touchkey_of_match[] = {
335 {
336 .compatible = "cypress,tm2-touchkey",
337 .data = &tm2_touchkey_variant,
338 }, {
339 .compatible = "cypress,midas-touchkey",
340 .data = &midas_touchkey_variant,
341 }, {
342 .compatible = "cypress,aries-touchkey",
343 .data = &aries_touchkey_variant,
344 }, {
345 .compatible = "coreriver,tc360-touchkey",
346 .data = &tc360_touchkey_variant,
347 },
348 { },
349};
350MODULE_DEVICE_TABLE(of, tm2_touchkey_of_match);
351
352static struct i2c_driver tm2_touchkey_driver = {
353 .driver = {
354 .name = TM2_TOUCHKEY_DEV_NAME,
355 .pm = pm_sleep_ptr(&tm2_touchkey_pm_ops),
356 .of_match_table = tm2_touchkey_of_match,
357 },
358 .probe = tm2_touchkey_probe,
359 .id_table = tm2_touchkey_id_table,
360};
361module_i2c_driver(tm2_touchkey_driver);
362
363MODULE_AUTHOR("Beomho Seo <[email protected]>");
364MODULE_AUTHOR("Jaechul Lee <[email protected]>");
365MODULE_DESCRIPTION("Samsung touchkey driver");
366MODULE_LICENSE("GPL v2");