1 files changed, 238 insertions, 0 deletions
diff --git a/drivers/input/keyboard/cypress-sf.c b/drivers/input/keyboard/cypress-sf.c
new file mode 100644
index 000000000..9a23eed6a
--- /dev/null
+++ b/drivers/input/keyboard/cypress-sf.c
@@ -0,0 +1,238 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Cypress StreetFighter Touchkey Driver
+ *
+ * Copyright (c) 2021 Yassine Oudjana <y.oudjana@protonmail.com>
+ */
+
+#include <linux/bitmap.h>
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/pm.h>
+#include <linux/regulator/consumer.h>
+
+#define CYPRESS_SF_DEV_NAME "cypress-sf"
+
+#define CYPRESS_SF_REG_BUTTON_STATUS	0x4a
+
+struct cypress_sf_data {
+	struct i2c_client *client;
+	struct input_dev *input_dev;
+	struct regulator_bulk_data regulators[2];
+	u32 *keycodes;
+	unsigned long keystates;
+	int num_keys;
+};
+
+static irqreturn_t cypress_sf_irq_handler(int irq, void *devid)
+{
+	struct cypress_sf_data *touchkey = devid;
+	unsigned long keystates, changed;
+	bool new_state;
+	int val, key;
+
+	val = i2c_smbus_read_byte_data(touchkey->client,
+				       CYPRESS_SF_REG_BUTTON_STATUS);
+	if (val < 0) {
+		dev_err(&touchkey->client->dev,
+			"Failed to read button status: %d", val);
+		return IRQ_NONE;
+	}
+	keystates = val;
+
+	bitmap_xor(&changed, &keystates, &touchkey->keystates,
+		   touchkey->num_keys);
+
+	for_each_set_bit(key, &changed, touchkey->num_keys) {
+		new_state = keystates & BIT(key);
+		dev_dbg(&touchkey->client->dev,
+			"Key %d changed to %d", key, new_state);
+		input_report_key(touchkey->input_dev,
+				 touchkey->keycodes[key], new_state);
+	}
+
+	input_sync(touchkey->input_dev);
+	touchkey->keystates = keystates;
+
+	return IRQ_HANDLED;
+}
+
+static void cypress_sf_disable_regulators(void *arg)
+{
+	struct cypress_sf_data *touchkey = arg;
+
+	regulator_bulk_disable(ARRAY_SIZE(touchkey->regulators),
+			       touchkey->regulators);
+}
+
+static int cypress_sf_probe(struct i2c_client *client)
+{
+	struct cypress_sf_data *touchkey;
+	int key, error;
+
+	touchkey = devm_kzalloc(&client->dev, sizeof(*touchkey), GFP_KERNEL);
+	if (!touchkey)
+		return -ENOMEM;
+
+	touchkey->client = client;
+	i2c_set_clientdata(client, touchkey);
+
+	touchkey->regulators[0].supply = "vdd";
+	touchkey->regulators[1].supply = "avdd";
+
+	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;
+	}
+
+	touchkey->num_keys = device_property_read_u32_array(&client->dev,
+							    "linux,keycodes",
+							    NULL, 0);
+	if (touchkey->num_keys < 0) {
+		/* Default key count */
+		touchkey->num_keys = 2;
+	}
+
+	touchkey->keycodes = devm_kcalloc(&client->dev,
+					  touchkey->num_keys,
+					  sizeof(*touchkey->keycodes),
+					  GFP_KERNEL);
+	if (!touchkey->keycodes)
+		return -ENOMEM;
+
+	error = device_property_read_u32_array(&client->dev, "linux,keycodes",
+					       touchkey->keycodes,
+					       touchkey->num_keys);
+
+	if (error) {
+		dev_warn(&client->dev,
+			 "Failed to read keycodes: %d, using defaults\n",
+			 error);
+
+		/* Default keycodes */
+		touchkey->keycodes[0] = KEY_BACK;
+		touchkey->keycodes[1] = KEY_MENU;
+	}
+
+	error = regulator_bulk_enable(ARRAY_SIZE(touchkey->regulators),
+				      touchkey->regulators);
+	if (error) {
+		dev_err(&client->dev,
+			"Failed to enable regulators: %d\n", error);
+		return error;
+	}
+
+	error = devm_add_action_or_reset(&client->dev,
+					 cypress_sf_disable_regulators,
+					 touchkey);
+	if (error)
+		return error;
+
+	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 = CYPRESS_SF_DEV_NAME;
+	touchkey->input_dev->id.bustype = BUS_I2C;
+
+	for (key = 0; key < touchkey->num_keys; ++key)
+		input_set_capability(touchkey->input_dev,
+				     EV_KEY, touchkey->keycodes[key]);
+
+	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, cypress_sf_irq_handler,
+					  IRQF_ONESHOT,
+					  CYPRESS_SF_DEV_NAME, touchkey);
+	if (error) {
+		dev_err(&client->dev,
+			"Failed to register threaded irq: %d", error);
+		return error;
+	}
+
+	return 0;
+};
+
+static int __maybe_unused cypress_sf_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct cypress_sf_data *touchkey = i2c_get_clientdata(client);
+	int error;
+
+	disable_irq(client->irq);
+
+	error = regulator_bulk_disable(ARRAY_SIZE(touchkey->regulators),
+				       touchkey->regulators);
+	if (error) {
+		dev_err(dev, "Failed to disable regulators: %d", error);
+		enable_irq(client->irq);
+		return error;
+	}
+
+	return 0;
+}
+
+static int __maybe_unused cypress_sf_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct cypress_sf_data *touchkey = i2c_get_clientdata(client);
+	int error;
+
+	error = regulator_bulk_enable(ARRAY_SIZE(touchkey->regulators),
+				      touchkey->regulators);
+	if (error) {
+		dev_err(dev, "Failed to enable regulators: %d", error);
+		return error;
+	}
+
+	enable_irq(client->irq);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(cypress_sf_pm_ops,
+			 cypress_sf_suspend, cypress_sf_resume);
+
+static struct i2c_device_id cypress_sf_id_table[] = {
+	{ CYPRESS_SF_DEV_NAME, 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, cypress_sf_id_table);
+
+#ifdef CONFIG_OF
+static const struct of_device_id cypress_sf_of_match[] = {
+	{ .compatible = "cypress,sf3155", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, cypress_sf_of_match);
+#endif
+
+static struct i2c_driver cypress_sf_driver = {
+	.driver = {
+		.name = CYPRESS_SF_DEV_NAME,
+		.pm = &cypress_sf_pm_ops,
+		.of_match_table = of_match_ptr(cypress_sf_of_match),
+	},
+	.id_table = cypress_sf_id_table,
+	.probe_new = cypress_sf_probe,
+};
+module_i2c_driver(cypress_sf_driver);
+
+MODULE_AUTHOR("Yassine Oudjana <y.oudjana@protonmail.com>");
+MODULE_DESCRIPTION("Cypress StreetFighter Touchkey Driver");
+MODULE_LICENSE("GPL v2");