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Diffstat (limited to 'drivers/input/keyboard/qt2160.c')
-rw-r--r--drivers/input/keyboard/qt2160.c415
1 files changed, 415 insertions, 0 deletions
diff --git a/drivers/input/keyboard/qt2160.c b/drivers/input/keyboard/qt2160.c
new file mode 100644
index 0000000000..7e3b09642a
--- /dev/null
+++ b/drivers/input/keyboard/qt2160.c
@@ -0,0 +1,415 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * qt2160.c - Atmel AT42QT2160 Touch Sense Controller
+ *
+ * Copyright (C) 2009 Raphael Derosso Pereira <raphaelpereira@gmail.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/i2c.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+
+#define QT2160_VALID_CHIPID 0x11
+
+#define QT2160_CMD_CHIPID 0
+#define QT2160_CMD_CODEVER 1
+#define QT2160_CMD_GSTAT 2
+#define QT2160_CMD_KEYS3 3
+#define QT2160_CMD_KEYS4 4
+#define QT2160_CMD_SLIDE 5
+#define QT2160_CMD_GPIOS 6
+#define QT2160_CMD_SUBVER 7
+#define QT2160_CMD_CALIBRATE 10
+#define QT2160_CMD_DRIVE_X 70
+#define QT2160_CMD_PWMEN_X 74
+#define QT2160_CMD_PWM_DUTY 76
+
+#define QT2160_NUM_LEDS_X 8
+
+#define QT2160_CYCLE_INTERVAL 2000 /* msec - 2 sec */
+
+static unsigned char qt2160_key2code[] = {
+ KEY_0, KEY_1, KEY_2, KEY_3,
+ KEY_4, KEY_5, KEY_6, KEY_7,
+ KEY_8, KEY_9, KEY_A, KEY_B,
+ KEY_C, KEY_D, KEY_E, KEY_F,
+};
+
+#ifdef CONFIG_LEDS_CLASS
+struct qt2160_led {
+ struct qt2160_data *qt2160;
+ struct led_classdev cdev;
+ char name[32];
+ int id;
+ enum led_brightness brightness;
+};
+#endif
+
+struct qt2160_data {
+ struct i2c_client *client;
+ struct input_dev *input;
+ unsigned short keycodes[ARRAY_SIZE(qt2160_key2code)];
+ u16 key_matrix;
+#ifdef CONFIG_LEDS_CLASS
+ struct qt2160_led leds[QT2160_NUM_LEDS_X];
+#endif
+};
+
+static int qt2160_read(struct i2c_client *client, u8 reg);
+static int qt2160_write(struct i2c_client *client, u8 reg, u8 data);
+
+#ifdef CONFIG_LEDS_CLASS
+
+static int qt2160_led_set(struct led_classdev *cdev,
+ enum led_brightness value)
+{
+ struct qt2160_led *led = container_of(cdev, struct qt2160_led, cdev);
+ struct qt2160_data *qt2160 = led->qt2160;
+ struct i2c_client *client = qt2160->client;
+ u32 drive, pwmen;
+
+ if (value != led->brightness) {
+ drive = qt2160_read(client, QT2160_CMD_DRIVE_X);
+ pwmen = qt2160_read(client, QT2160_CMD_PWMEN_X);
+ if (value != LED_OFF) {
+ drive |= BIT(led->id);
+ pwmen |= BIT(led->id);
+
+ } else {
+ drive &= ~BIT(led->id);
+ pwmen &= ~BIT(led->id);
+ }
+ qt2160_write(client, QT2160_CMD_DRIVE_X, drive);
+ qt2160_write(client, QT2160_CMD_PWMEN_X, pwmen);
+
+ /*
+ * Changing this register will change the brightness
+ * of every LED in the qt2160. It's a HW limitation.
+ */
+ if (value != LED_OFF)
+ qt2160_write(client, QT2160_CMD_PWM_DUTY, value);
+
+ led->brightness = value;
+ }
+
+ return 0;
+}
+
+#endif /* CONFIG_LEDS_CLASS */
+
+static int qt2160_read_block(struct i2c_client *client,
+ u8 inireg, u8 *buffer, unsigned int count)
+{
+ int error, idx = 0;
+
+ /*
+ * Can't use SMBus block data read. Check for I2C functionality to speed
+ * things up whenever possible. Otherwise we will be forced to read
+ * sequentially.
+ */
+ if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+
+ error = i2c_smbus_write_byte(client, inireg + idx);
+ if (error) {
+ dev_err(&client->dev,
+ "couldn't send request. Returned %d\n", error);
+ return error;
+ }
+
+ error = i2c_master_recv(client, buffer, count);
+ if (error != count) {
+ dev_err(&client->dev,
+ "couldn't read registers. Returned %d bytes\n", error);
+ return error;
+ }
+ } else {
+
+ while (count--) {
+ int data;
+
+ error = i2c_smbus_write_byte(client, inireg + idx);
+ if (error) {
+ dev_err(&client->dev,
+ "couldn't send request. Returned %d\n", error);
+ return error;
+ }
+
+ data = i2c_smbus_read_byte(client);
+ if (data < 0) {
+ dev_err(&client->dev,
+ "couldn't read register. Returned %d\n", data);
+ return data;
+ }
+
+ buffer[idx++] = data;
+ }
+ }
+
+ return 0;
+}
+
+static void qt2160_get_key_matrix(struct input_dev *input)
+{
+ struct qt2160_data *qt2160 = input_get_drvdata(input);
+ struct i2c_client *client = qt2160->client;
+ u8 regs[6];
+ u16 old_matrix, new_matrix;
+ int ret, i, mask;
+
+ dev_dbg(&client->dev, "requesting keys...\n");
+
+ /*
+ * Read all registers from General Status Register
+ * to GPIOs register
+ */
+ ret = qt2160_read_block(client, QT2160_CMD_GSTAT, regs, 6);
+ if (ret) {
+ dev_err(&client->dev,
+ "could not perform chip read.\n");
+ return;
+ }
+
+ old_matrix = qt2160->key_matrix;
+ qt2160->key_matrix = new_matrix = (regs[2] << 8) | regs[1];
+
+ mask = 0x01;
+ for (i = 0; i < 16; ++i, mask <<= 1) {
+ int keyval = new_matrix & mask;
+
+ if ((old_matrix & mask) != keyval) {
+ input_report_key(input, qt2160->keycodes[i], keyval);
+ dev_dbg(&client->dev, "key %d %s\n",
+ i, keyval ? "pressed" : "released");
+ }
+ }
+
+ input_sync(input);
+}
+
+static irqreturn_t qt2160_irq(int irq, void *data)
+{
+ struct input_dev *input = data;
+
+ qt2160_get_key_matrix(input);
+
+ return IRQ_HANDLED;
+}
+
+static int qt2160_read(struct i2c_client *client, u8 reg)
+{
+ int ret;
+
+ ret = i2c_smbus_write_byte(client, reg);
+ if (ret) {
+ dev_err(&client->dev,
+ "couldn't send request. Returned %d\n", ret);
+ return ret;
+ }
+
+ ret = i2c_smbus_read_byte(client);
+ if (ret < 0) {
+ dev_err(&client->dev,
+ "couldn't read register. Returned %d\n", ret);
+ return ret;
+ }
+
+ return ret;
+}
+
+static int qt2160_write(struct i2c_client *client, u8 reg, u8 data)
+{
+ int ret;
+
+ ret = i2c_smbus_write_byte_data(client, reg, data);
+ if (ret < 0)
+ dev_err(&client->dev,
+ "couldn't write data. Returned %d\n", ret);
+
+ return ret;
+}
+
+#ifdef CONFIG_LEDS_CLASS
+
+static int qt2160_register_leds(struct qt2160_data *qt2160)
+{
+ struct i2c_client *client = qt2160->client;
+ int error;
+ int i;
+
+ for (i = 0; i < QT2160_NUM_LEDS_X; i++) {
+ struct qt2160_led *led = &qt2160->leds[i];
+
+ snprintf(led->name, sizeof(led->name), "qt2160:x%d", i);
+ led->cdev.name = led->name;
+ led->cdev.brightness_set_blocking = qt2160_led_set;
+ led->cdev.brightness = LED_OFF;
+ led->id = i;
+ led->qt2160 = qt2160;
+
+ error = devm_led_classdev_register(&client->dev, &led->cdev);
+ if (error)
+ return error;
+ }
+
+ /* Tur off LEDs */
+ qt2160_write(client, QT2160_CMD_DRIVE_X, 0);
+ qt2160_write(client, QT2160_CMD_PWMEN_X, 0);
+ qt2160_write(client, QT2160_CMD_PWM_DUTY, 0);
+
+ return 0;
+}
+
+#else
+
+static inline int qt2160_register_leds(struct qt2160_data *qt2160)
+{
+ return 0;
+}
+
+#endif
+
+static bool qt2160_identify(struct i2c_client *client)
+{
+ int id, ver, rev;
+
+ /* Read Chid ID to check if chip is valid */
+ id = qt2160_read(client, QT2160_CMD_CHIPID);
+ if (id != QT2160_VALID_CHIPID) {
+ dev_err(&client->dev, "ID %d not supported\n", id);
+ return false;
+ }
+
+ /* Read chip firmware version */
+ ver = qt2160_read(client, QT2160_CMD_CODEVER);
+ if (ver < 0) {
+ dev_err(&client->dev, "could not get firmware version\n");
+ return false;
+ }
+
+ /* Read chip firmware revision */
+ rev = qt2160_read(client, QT2160_CMD_SUBVER);
+ if (rev < 0) {
+ dev_err(&client->dev, "could not get firmware revision\n");
+ return false;
+ }
+
+ dev_info(&client->dev, "AT42QT2160 firmware version %d.%d.%d\n",
+ ver >> 4, ver & 0xf, rev);
+
+ return true;
+}
+
+static int qt2160_probe(struct i2c_client *client)
+{
+ struct qt2160_data *qt2160;
+ struct input_dev *input;
+ int i;
+ int error;
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE)) {
+ dev_err(&client->dev, "%s adapter not supported\n",
+ dev_driver_string(&client->adapter->dev));
+ return -ENODEV;
+ }
+
+ if (!qt2160_identify(client))
+ return -ENODEV;
+
+ /* Chip is valid and active. Allocate structure */
+ qt2160 = devm_kzalloc(&client->dev, sizeof(*qt2160), GFP_KERNEL);
+ if (!qt2160)
+ return -ENOMEM;
+
+ input = devm_input_allocate_device(&client->dev);
+ if (!input)
+ return -ENOMEM;
+
+ qt2160->client = client;
+ qt2160->input = input;
+
+ input->name = "AT42QT2160 Touch Sense Keyboard";
+ input->id.bustype = BUS_I2C;
+
+ input->keycode = qt2160->keycodes;
+ input->keycodesize = sizeof(qt2160->keycodes[0]);
+ input->keycodemax = ARRAY_SIZE(qt2160_key2code);
+
+ __set_bit(EV_KEY, input->evbit);
+ __clear_bit(EV_REP, input->evbit);
+ for (i = 0; i < ARRAY_SIZE(qt2160_key2code); i++) {
+ qt2160->keycodes[i] = qt2160_key2code[i];
+ __set_bit(qt2160_key2code[i], input->keybit);
+ }
+ __clear_bit(KEY_RESERVED, input->keybit);
+
+ input_set_drvdata(input, qt2160);
+
+ /* Calibrate device */
+ error = qt2160_write(client, QT2160_CMD_CALIBRATE, 1);
+ if (error) {
+ dev_err(&client->dev, "failed to calibrate device\n");
+ return error;
+ }
+
+ if (client->irq) {
+ error = devm_request_threaded_irq(&client->dev, client->irq,
+ NULL, qt2160_irq,
+ IRQF_ONESHOT,
+ "qt2160", input);
+ if (error) {
+ dev_err(&client->dev,
+ "failed to allocate irq %d\n", client->irq);
+ return error;
+ }
+ } else {
+ error = input_setup_polling(input, qt2160_get_key_matrix);
+ if (error) {
+ dev_err(&client->dev, "Failed to setup polling\n");
+ return error;
+ }
+ input_set_poll_interval(input, QT2160_CYCLE_INTERVAL);
+ }
+
+ error = qt2160_register_leds(qt2160);
+ if (error) {
+ dev_err(&client->dev, "Failed to register leds\n");
+ return error;
+ }
+
+ error = input_register_device(qt2160->input);
+ if (error) {
+ dev_err(&client->dev,
+ "Failed to register input device\n");
+ return error;
+ }
+
+ return 0;
+}
+
+static const struct i2c_device_id qt2160_idtable[] = {
+ { "qt2160", 0, },
+ { }
+};
+
+MODULE_DEVICE_TABLE(i2c, qt2160_idtable);
+
+static struct i2c_driver qt2160_driver = {
+ .driver = {
+ .name = "qt2160",
+ },
+
+ .id_table = qt2160_idtable,
+ .probe = qt2160_probe,
+};
+
+module_i2c_driver(qt2160_driver);
+
+MODULE_AUTHOR("Raphael Derosso Pereira <raphaelpereira@gmail.com>");
+MODULE_DESCRIPTION("Driver for AT42QT2160 Touch Sensor");
+MODULE_LICENSE("GPL");