1 // SPDX-License-Identifier: GPL-2.0-only
3 * TM2 touchkey device driver
5 * Copyright 2005 Phil Blundell
6 * Copyright 2016 Samsung Electronics Co., Ltd.
8 * Author: Beomho Seo <beomho.seo@samsung.com>
9 * Author: Jaechul Lee <jcsing.lee@samsung.com>
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>
22 #include <linux/of_device.h>
24 #include <linux/regulator/consumer.h>
26 #define TM2_TOUCHKEY_DEV_NAME "tm2-touchkey"
28 #define ARIES_TOUCHKEY_CMD_LED_ON 0x1
29 #define ARIES_TOUCHKEY_CMD_LED_OFF 0x2
30 #define TM2_TOUCHKEY_CMD_LED_ON 0x10
31 #define TM2_TOUCHKEY_CMD_LED_OFF 0x20
32 #define TM2_TOUCHKEY_BIT_PRESS_EV BIT(3)
33 #define TM2_TOUCHKEY_BIT_KEYCODE GENMASK(2, 0)
34 #define TM2_TOUCHKEY_LED_VOLTAGE_MIN 2500000
35 #define TM2_TOUCHKEY_LED_VOLTAGE_MAX 3300000
37 struct touchkey_variant {
46 struct tm2_touchkey_data {
47 struct i2c_client *client;
48 struct input_dev *input_dev;
49 struct led_classdev led_dev;
50 struct regulator *vdd;
51 struct regulator_bulk_data regulators[2];
52 const struct touchkey_variant *variant;
57 static const struct touchkey_variant tm2_touchkey_variant = {
60 .cmd_led_on = TM2_TOUCHKEY_CMD_LED_ON,
61 .cmd_led_off = TM2_TOUCHKEY_CMD_LED_OFF,
64 static const struct touchkey_variant midas_touchkey_variant = {
67 .cmd_led_on = TM2_TOUCHKEY_CMD_LED_ON,
68 .cmd_led_off = TM2_TOUCHKEY_CMD_LED_OFF,
71 static struct touchkey_variant aries_touchkey_variant = {
73 .fixed_regulator = true,
74 .cmd_led_on = ARIES_TOUCHKEY_CMD_LED_ON,
75 .cmd_led_off = ARIES_TOUCHKEY_CMD_LED_OFF,
78 static int tm2_touchkey_led_brightness_set(struct led_classdev *led_dev,
79 enum led_brightness brightness)
81 struct tm2_touchkey_data *touchkey =
82 container_of(led_dev, struct tm2_touchkey_data, led_dev);
86 if (brightness == LED_OFF) {
87 volt = TM2_TOUCHKEY_LED_VOLTAGE_MIN;
88 data = touchkey->variant->cmd_led_off;
90 volt = TM2_TOUCHKEY_LED_VOLTAGE_MAX;
91 data = touchkey->variant->cmd_led_on;
94 if (!touchkey->variant->fixed_regulator)
95 regulator_set_voltage(touchkey->vdd, volt, volt);
97 return touchkey->variant->no_reg ?
98 i2c_smbus_write_byte(touchkey->client, data) :
99 i2c_smbus_write_byte_data(touchkey->client,
100 touchkey->variant->base_reg, data);
103 static int tm2_touchkey_power_enable(struct tm2_touchkey_data *touchkey)
107 error = regulator_bulk_enable(ARRAY_SIZE(touchkey->regulators),
108 touchkey->regulators);
112 /* waiting for device initialization, at least 150ms */
118 static void tm2_touchkey_power_disable(void *data)
120 struct tm2_touchkey_data *touchkey = data;
122 regulator_bulk_disable(ARRAY_SIZE(touchkey->regulators),
123 touchkey->regulators);
126 static irqreturn_t tm2_touchkey_irq_handler(int irq, void *devid)
128 struct tm2_touchkey_data *touchkey = devid;
133 if (touchkey->variant->no_reg)
134 data = i2c_smbus_read_byte(touchkey->client);
136 data = i2c_smbus_read_byte_data(touchkey->client,
137 touchkey->variant->keycode_reg);
139 dev_err(&touchkey->client->dev,
140 "failed to read i2c data: %d\n", data);
144 index = (data & TM2_TOUCHKEY_BIT_KEYCODE) - 1;
145 if (index < 0 || index >= touchkey->num_keycodes) {
146 dev_warn(&touchkey->client->dev,
147 "invalid keycode index %d\n", index);
151 if (data & TM2_TOUCHKEY_BIT_PRESS_EV) {
152 for (i = 0; i < touchkey->num_keycodes; i++)
153 input_report_key(touchkey->input_dev,
154 touchkey->keycodes[i], 0);
156 input_report_key(touchkey->input_dev,
157 touchkey->keycodes[index], 1);
160 input_sync(touchkey->input_dev);
163 if (touchkey->variant->fixed_regulator &&
164 data & TM2_TOUCHKEY_BIT_PRESS_EV) {
165 /* touch turns backlight on, so make sure we're in sync */
166 if (touchkey->led_dev.brightness == LED_OFF)
167 tm2_touchkey_led_brightness_set(&touchkey->led_dev,
174 static int tm2_touchkey_probe(struct i2c_client *client,
175 const struct i2c_device_id *id)
177 struct device_node *np = client->dev.of_node;
178 struct tm2_touchkey_data *touchkey;
182 if (!i2c_check_functionality(client->adapter,
183 I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA)) {
184 dev_err(&client->dev, "incompatible I2C adapter\n");
188 touchkey = devm_kzalloc(&client->dev, sizeof(*touchkey), GFP_KERNEL);
192 touchkey->client = client;
193 i2c_set_clientdata(client, touchkey);
195 touchkey->variant = of_device_get_match_data(&client->dev);
197 touchkey->regulators[0].supply = "vcc";
198 touchkey->regulators[1].supply = "vdd";
199 error = devm_regulator_bulk_get(&client->dev,
200 ARRAY_SIZE(touchkey->regulators),
201 touchkey->regulators);
203 dev_err(&client->dev, "failed to get regulators: %d\n", error);
207 /* Save VDD for easy access */
208 touchkey->vdd = touchkey->regulators[1].consumer;
210 touchkey->num_keycodes = of_property_read_variable_u32_array(np,
211 "linux,keycodes", touchkey->keycodes, 0,
212 ARRAY_SIZE(touchkey->keycodes));
213 if (touchkey->num_keycodes <= 0) {
214 /* default keycodes */
215 touchkey->keycodes[0] = KEY_PHONE;
216 touchkey->keycodes[1] = KEY_BACK;
217 touchkey->num_keycodes = 2;
220 error = tm2_touchkey_power_enable(touchkey);
222 dev_err(&client->dev, "failed to power up device: %d\n", error);
226 error = devm_add_action_or_reset(&client->dev,
227 tm2_touchkey_power_disable, touchkey);
229 dev_err(&client->dev,
230 "failed to install poweroff handler: %d\n", error);
235 touchkey->input_dev = devm_input_allocate_device(&client->dev);
236 if (!touchkey->input_dev) {
237 dev_err(&client->dev, "failed to allocate input device\n");
241 touchkey->input_dev->name = TM2_TOUCHKEY_DEV_NAME;
242 touchkey->input_dev->id.bustype = BUS_I2C;
244 for (i = 0; i < touchkey->num_keycodes; i++)
245 input_set_capability(touchkey->input_dev, EV_KEY,
246 touchkey->keycodes[i]);
248 error = input_register_device(touchkey->input_dev);
250 dev_err(&client->dev,
251 "failed to register input device: %d\n", error);
255 error = devm_request_threaded_irq(&client->dev, client->irq,
256 NULL, tm2_touchkey_irq_handler,
258 TM2_TOUCHKEY_DEV_NAME, touchkey);
260 dev_err(&client->dev,
261 "failed to request threaded irq: %d\n", error);
266 touchkey->led_dev.name = TM2_TOUCHKEY_DEV_NAME;
267 touchkey->led_dev.brightness = LED_ON;
268 touchkey->led_dev.max_brightness = LED_ON;
269 touchkey->led_dev.brightness_set_blocking =
270 tm2_touchkey_led_brightness_set;
272 error = devm_led_classdev_register(&client->dev, &touchkey->led_dev);
274 dev_err(&client->dev,
275 "failed to register touchkey led: %d\n", error);
279 if (touchkey->variant->fixed_regulator)
280 tm2_touchkey_led_brightness_set(&touchkey->led_dev, LED_ON);
285 static int __maybe_unused tm2_touchkey_suspend(struct device *dev)
287 struct i2c_client *client = to_i2c_client(dev);
288 struct tm2_touchkey_data *touchkey = i2c_get_clientdata(client);
290 disable_irq(client->irq);
291 tm2_touchkey_power_disable(touchkey);
296 static int __maybe_unused tm2_touchkey_resume(struct device *dev)
298 struct i2c_client *client = to_i2c_client(dev);
299 struct tm2_touchkey_data *touchkey = i2c_get_clientdata(client);
302 enable_irq(client->irq);
304 ret = tm2_touchkey_power_enable(touchkey);
306 dev_err(dev, "failed to enable power: %d\n", ret);
311 static SIMPLE_DEV_PM_OPS(tm2_touchkey_pm_ops,
312 tm2_touchkey_suspend, tm2_touchkey_resume);
314 static const struct i2c_device_id tm2_touchkey_id_table[] = {
315 { TM2_TOUCHKEY_DEV_NAME, 0 },
318 MODULE_DEVICE_TABLE(i2c, tm2_touchkey_id_table);
320 static const struct of_device_id tm2_touchkey_of_match[] = {
322 .compatible = "cypress,tm2-touchkey",
323 .data = &tm2_touchkey_variant,
325 .compatible = "cypress,midas-touchkey",
326 .data = &midas_touchkey_variant,
328 .compatible = "cypress,aries-touchkey",
329 .data = &aries_touchkey_variant,
333 MODULE_DEVICE_TABLE(of, tm2_touchkey_of_match);
335 static struct i2c_driver tm2_touchkey_driver = {
337 .name = TM2_TOUCHKEY_DEV_NAME,
338 .pm = &tm2_touchkey_pm_ops,
339 .of_match_table = of_match_ptr(tm2_touchkey_of_match),
341 .probe = tm2_touchkey_probe,
342 .id_table = tm2_touchkey_id_table,
344 module_i2c_driver(tm2_touchkey_driver);
346 MODULE_AUTHOR("Beomho Seo <beomho.seo@samsung.com>");
347 MODULE_AUTHOR("Jaechul Lee <jcsing.lee@samsung.com>");
348 MODULE_DESCRIPTION("Samsung touchkey driver");
349 MODULE_LICENSE("GPL v2");