1 files changed, 366 insertions, 0 deletions
diff --git a/drivers/input/keyboard/tm2-touchkey.c b/drivers/input/keyboard/tm2-touchkey.c
new file mode 100644
index 0000000000..0fd761ae05
--- /dev/null
+++ b/drivers/input/keyboard/tm2-touchkey.c
@@ -0,0 +1,366 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * TM2 touchkey device driver
+ *
+ * Copyright 2005 Phil Blundell
+ * Copyright 2016 Samsung Electronics Co., Ltd.
+ *
+ * Author: Beomho Seo <beomho.seo@samsung.com>
+ * Author: Jaechul Lee <jcsing.lee@samsung.com>
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pm.h>
+#include <linux/regulator/consumer.h>
+
+#define TM2_TOUCHKEY_DEV_NAME		"tm2-touchkey"
+
+#define ARIES_TOUCHKEY_CMD_LED_ON	0x1
+#define ARIES_TOUCHKEY_CMD_LED_OFF	0x2
+#define TM2_TOUCHKEY_CMD_LED_ON		0x10
+#define TM2_TOUCHKEY_CMD_LED_OFF	0x20
+#define TM2_TOUCHKEY_BIT_PRESS_EV	BIT(3)
+#define TM2_TOUCHKEY_BIT_KEYCODE	GENMASK(2, 0)
+#define TM2_TOUCHKEY_LED_VOLTAGE_MIN	2500000
+#define TM2_TOUCHKEY_LED_VOLTAGE_MAX	3300000
+
+struct touchkey_variant {
+	u8 keycode_reg;
+	u8 base_reg;
+	u8 cmd_led_on;
+	u8 cmd_led_off;
+	bool no_reg;
+	bool fixed_regulator;
+};
+
+struct tm2_touchkey_data {
+	struct i2c_client *client;
+	struct input_dev *input_dev;
+	struct led_classdev led_dev;
+	struct regulator *vdd;
+	struct regulator_bulk_data regulators[3];
+	const struct touchkey_variant *variant;
+	u32 keycodes[4];
+	int num_keycodes;
+};
+
+static const struct touchkey_variant tm2_touchkey_variant = {
+	.keycode_reg = 0x03,
+	.base_reg = 0x00,
+	.cmd_led_on = TM2_TOUCHKEY_CMD_LED_ON,
+	.cmd_led_off = TM2_TOUCHKEY_CMD_LED_OFF,
+};
+
+static const struct touchkey_variant midas_touchkey_variant = {
+	.keycode_reg = 0x00,
+	.base_reg = 0x00,
+	.cmd_led_on = TM2_TOUCHKEY_CMD_LED_ON,
+	.cmd_led_off = TM2_TOUCHKEY_CMD_LED_OFF,
+};
+
+static struct touchkey_variant aries_touchkey_variant = {
+	.no_reg = true,
+	.fixed_regulator = true,
+	.cmd_led_on = ARIES_TOUCHKEY_CMD_LED_ON,
+	.cmd_led_off = ARIES_TOUCHKEY_CMD_LED_OFF,
+};
+
+static const struct touchkey_variant tc360_touchkey_variant = {
+	.keycode_reg = 0x00,
+	.base_reg = 0x00,
+	.fixed_regulator = true,
+	.cmd_led_on = TM2_TOUCHKEY_CMD_LED_ON,
+	.cmd_led_off = TM2_TOUCHKEY_CMD_LED_OFF,
+};
+
+static int tm2_touchkey_led_brightness_set(struct led_classdev *led_dev,
+					    enum led_brightness brightness)
+{
+	struct tm2_touchkey_data *touchkey =
+		container_of(led_dev, struct tm2_touchkey_data, led_dev);
+	u32 volt;
+	u8 data;
+
+	if (brightness == LED_OFF) {
+		volt = TM2_TOUCHKEY_LED_VOLTAGE_MIN;
+		data = touchkey->variant->cmd_led_off;
+	} else {
+		volt = TM2_TOUCHKEY_LED_VOLTAGE_MAX;
+		data = touchkey->variant->cmd_led_on;
+	}
+
+	if (!touchkey->variant->fixed_regulator)
+		regulator_set_voltage(touchkey->vdd, volt, volt);
+
+	return touchkey->variant->no_reg ?
+		i2c_smbus_write_byte(touchkey->client, data) :
+		i2c_smbus_write_byte_data(touchkey->client,
+					  touchkey->variant->base_reg, data);
+}
+
+static int tm2_touchkey_power_enable(struct tm2_touchkey_data *touchkey)
+{
+	int error;
+
+	error = regulator_bulk_enable(ARRAY_SIZE(touchkey->regulators),
+				      touchkey->regulators);
+	if (error)
+		return error;
+
+	/* waiting for device initialization, at least 150ms */
+	msleep(150);
+
+	return 0;
+}
+
+static void tm2_touchkey_power_disable(void *data)
+{
+	struct tm2_touchkey_data *touchkey = data;
+
+	regulator_bulk_disable(ARRAY_SIZE(touchkey->regulators),
+			       touchkey->regulators);
+}
+
+static irqreturn_t tm2_touchkey_irq_handler(int irq, void *devid)
+{
+	struct tm2_touchkey_data *touchkey = devid;
+	int data;
+	int index;
+	int i;
+
+	if (touchkey->variant->no_reg)
+		data = i2c_smbus_read_byte(touchkey->client);
+	else
+		data = i2c_smbus_read_byte_data(touchkey->client,
+						touchkey->variant->keycode_reg);
+	if (data < 0) {
+		dev_err(&touchkey->client->dev,
+			"failed to read i2c data: %d\n", data);
+		goto out;
+	}
+
+	index = (data & TM2_TOUCHKEY_BIT_KEYCODE) - 1;
+	if (index < 0 || index >= touchkey->num_keycodes) {
+		dev_warn(&touchkey->client->dev,
+			 "invalid keycode index %d\n", index);
+		goto out;
+	}
+
+	input_event(touchkey->input_dev, EV_MSC, MSC_SCAN, index);
+
+	if (data & TM2_TOUCHKEY_BIT_PRESS_EV) {
+		for (i = 0; i < touchkey->num_keycodes; i++)
+			input_report_key(touchkey->input_dev,
+					 touchkey->keycodes[i], 0);
+	} else {
+		input_report_key(touchkey->input_dev,
+				 touchkey->keycodes[index], 1);
+	}
+
+	input_sync(touchkey->input_dev);
+
+out:
+	if (touchkey->variant->fixed_regulator &&
+				data & TM2_TOUCHKEY_BIT_PRESS_EV) {
+		/* touch turns backlight on, so make sure we're in sync */
+		if (touchkey->led_dev.brightness == LED_OFF)
+			tm2_touchkey_led_brightness_set(&touchkey->led_dev,
+							LED_OFF);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int tm2_touchkey_probe(struct i2c_client *client)
+{
+	struct device_node *np = client->dev.of_node;
+	struct tm2_touchkey_data *touchkey;
+	int error;
+	int i;
+
+	if (!i2c_check_functionality(client->adapter,
+			I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA)) {
+		dev_err(&client->dev, "incompatible I2C adapter\n");
+		return -EIO;
+	}
+
+	touchkey = devm_kzalloc(&client->dev, sizeof(*touchkey), GFP_KERNEL);
+	if (!touchkey)
+		return -ENOMEM;
+
+	touchkey->client = client;
+	i2c_set_clientdata(client, touchkey);
+
+	touchkey->variant = of_device_get_match_data(&client->dev);
+
+	touchkey->regulators[0].supply = "vcc";
+	touchkey->regulators[1].supply = "vdd";
+	touchkey->regulators[2].supply = "vddio";
+	error = devm_regulator_bulk_get(&client->dev,
+					ARRAY_SIZE(touchkey->regulators),
+					touchkey->regulators);
+	if (error) {
+		dev_err(&client->dev, "failed to get regulators: %d\n", error);
+		return error;
+	}
+
+	/* Save VDD for easy access */
+	touchkey->vdd = touchkey->regulators[1].consumer;
+
+	touchkey->num_keycodes = of_property_read_variable_u32_array(np,
+					"linux,keycodes", touchkey->keycodes, 0,
+					ARRAY_SIZE(touchkey->keycodes));
+	if (touchkey->num_keycodes <= 0) {
+		/* default keycodes */
+		touchkey->keycodes[0] = KEY_PHONE;
+		touchkey->keycodes[1] = KEY_BACK;
+		touchkey->num_keycodes = 2;
+	}
+
+	error = tm2_touchkey_power_enable(touchkey);
+	if (error) {
+		dev_err(&client->dev, "failed to power up device: %d\n", error);
+		return error;
+	}
+
+	error = devm_add_action_or_reset(&client->dev,
+					 tm2_touchkey_power_disable, touchkey);
+	if (error) {
+		dev_err(&client->dev,
+			"failed to install poweroff handler: %d\n", error);
+		return error;
+	}
+
+	/* input device */
+	touchkey->input_dev = devm_input_allocate_device(&client->dev);
+	if (!touchkey->input_dev) {
+		dev_err(&client->dev, "failed to allocate input device\n");
+		return -ENOMEM;
+	}
+
+	touchkey->input_dev->name = TM2_TOUCHKEY_DEV_NAME;
+	touchkey->input_dev->id.bustype = BUS_I2C;
+
+	touchkey->input_dev->keycode = touchkey->keycodes;
+	touchkey->input_dev->keycodemax = touchkey->num_keycodes;
+	touchkey->input_dev->keycodesize = sizeof(touchkey->keycodes[0]);
+
+	input_set_capability(touchkey->input_dev, EV_MSC, MSC_SCAN);
+	for (i = 0; i < touchkey->num_keycodes; i++)
+		input_set_capability(touchkey->input_dev, EV_KEY,
+				     touchkey->keycodes[i]);
+
+	error = input_register_device(touchkey->input_dev);
+	if (error) {
+		dev_err(&client->dev,
+			"failed to register input device: %d\n", error);
+		return error;
+	}
+
+	error = devm_request_threaded_irq(&client->dev, client->irq,
+					  NULL, tm2_touchkey_irq_handler,
+					  IRQF_ONESHOT,
+					  TM2_TOUCHKEY_DEV_NAME, touchkey);
+	if (error) {
+		dev_err(&client->dev,
+			"failed to request threaded irq: %d\n", error);
+		return error;
+	}
+
+	/* led device */
+	touchkey->led_dev.name = TM2_TOUCHKEY_DEV_NAME;
+	touchkey->led_dev.brightness = LED_ON;
+	touchkey->led_dev.max_brightness = LED_ON;
+	touchkey->led_dev.brightness_set_blocking =
+					tm2_touchkey_led_brightness_set;
+
+	error = devm_led_classdev_register(&client->dev, &touchkey->led_dev);
+	if (error) {
+		dev_err(&client->dev,
+			"failed to register touchkey led: %d\n", error);
+		return error;
+	}
+
+	if (touchkey->variant->fixed_regulator)
+		tm2_touchkey_led_brightness_set(&touchkey->led_dev, LED_ON);
+
+	return 0;
+}
+
+static int tm2_touchkey_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct tm2_touchkey_data *touchkey = i2c_get_clientdata(client);
+
+	disable_irq(client->irq);
+	tm2_touchkey_power_disable(touchkey);
+
+	return 0;
+}
+
+static int tm2_touchkey_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct tm2_touchkey_data *touchkey = i2c_get_clientdata(client);
+	int ret;
+
+	enable_irq(client->irq);
+
+	ret = tm2_touchkey_power_enable(touchkey);
+	if (ret)
+		dev_err(dev, "failed to enable power: %d\n", ret);
+
+	return ret;
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(tm2_touchkey_pm_ops,
+				tm2_touchkey_suspend, tm2_touchkey_resume);
+
+static const struct i2c_device_id tm2_touchkey_id_table[] = {
+	{ TM2_TOUCHKEY_DEV_NAME, 0 },
+	{ },
+};
+MODULE_DEVICE_TABLE(i2c, tm2_touchkey_id_table);
+
+static const struct of_device_id tm2_touchkey_of_match[] = {
+	{
+		.compatible = "cypress,tm2-touchkey",
+		.data = &tm2_touchkey_variant,
+	}, {
+		.compatible = "cypress,midas-touchkey",
+		.data = &midas_touchkey_variant,
+	}, {
+		.compatible = "cypress,aries-touchkey",
+		.data = &aries_touchkey_variant,
+	}, {
+		.compatible = "coreriver,tc360-touchkey",
+		.data = &tc360_touchkey_variant,
+	},
+	{ },
+};
+MODULE_DEVICE_TABLE(of, tm2_touchkey_of_match);
+
+static struct i2c_driver tm2_touchkey_driver = {
+	.driver = {
+		.name = TM2_TOUCHKEY_DEV_NAME,
+		.pm = pm_sleep_ptr(&tm2_touchkey_pm_ops),
+		.of_match_table = tm2_touchkey_of_match,
+	},
+	.probe = tm2_touchkey_probe,
+	.id_table = tm2_touchkey_id_table,
+};
+module_i2c_driver(tm2_touchkey_driver);
+
+MODULE_AUTHOR("Beomho Seo <beomho.seo@samsung.com>");
+MODULE_AUTHOR("Jaechul Lee <jcsing.lee@samsung.com>");
+MODULE_DESCRIPTION("Samsung touchkey driver");
+MODULE_LICENSE("GPL v2");