--- /dev/null
+/*
+ * qt2160.c - Atmel AT42QT2160 Touch Sense Controller
+ *
+ * Copyright (C) 2009 Raphael Derosso Pereira <raphaelpereira@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#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 (2*HZ)
+
+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;
+ struct work_struct work;
+ char name[32];
+ int id;
+ enum led_brightness new_brightness;
+};
+#endif
+
+struct qt2160_data {
+ struct i2c_client *client;
+ struct input_dev *input;
+ struct delayed_work dwork;
+ spinlock_t lock; /* Protects canceling/rescheduling of dwork */
+ unsigned short keycodes[ARRAY_SIZE(qt2160_key2code)];
+ u16 key_matrix;
+#ifdef CONFIG_LEDS_CLASS
+ struct qt2160_led leds[QT2160_NUM_LEDS_X];
+ struct mutex led_lock;
+#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 void qt2160_led_work(struct work_struct *work)
+{
+ struct qt2160_led *led = container_of(work, struct qt2160_led, work);
+ struct qt2160_data *qt2160 = led->qt2160;
+ struct i2c_client *client = qt2160->client;
+ int value = led->new_brightness;
+ u32 drive, pwmen;
+
+ mutex_lock(&qt2160->led_lock);
+
+ drive = qt2160_read(client, QT2160_CMD_DRIVE_X);
+ pwmen = qt2160_read(client, QT2160_CMD_PWMEN_X);
+ if (value != LED_OFF) {
+ drive |= (1 << led->id);
+ pwmen |= (1 << led->id);
+
+ } else {
+ drive &= ~(1 << led->id);
+ pwmen &= ~(1 << 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);
+
+ mutex_unlock(&qt2160->led_lock);
+}
+
+static void qt2160_led_set(struct led_classdev *cdev,
+ enum led_brightness value)
+{
+ struct qt2160_led *led = container_of(cdev, struct qt2160_led, cdev);
+
+ led->new_brightness = value;
+ schedule_work(&led->work);
+}
+
+#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 int qt2160_get_key_matrix(struct qt2160_data *qt2160)
+{
+ struct i2c_client *client = qt2160->client;
+ struct input_dev *input = qt2160->input;
+ 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 ret;
+ }
+
+ 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);
+
+ return 0;
+}
+
+static irqreturn_t qt2160_irq(int irq, void *_qt2160)
+{
+ struct qt2160_data *qt2160 = _qt2160;
+ unsigned long flags;
+
+ spin_lock_irqsave(&qt2160->lock, flags);
+
+ mod_delayed_work(system_wq, &qt2160->dwork, 0);
+
+ spin_unlock_irqrestore(&qt2160->lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+static void qt2160_schedule_read(struct qt2160_data *qt2160)
+{
+ spin_lock_irq(&qt2160->lock);
+ schedule_delayed_work(&qt2160->dwork, QT2160_CYCLE_INTERVAL);
+ spin_unlock_irq(&qt2160->lock);
+}
+
+static void qt2160_worker(struct work_struct *work)
+{
+ struct qt2160_data *qt2160 =
+ container_of(work, struct qt2160_data, dwork.work);
+
+ dev_dbg(&qt2160->client->dev, "worker\n");
+
+ qt2160_get_key_matrix(qt2160);
+
+ /* Avoid device lock up by checking every so often */
+ qt2160_schedule_read(qt2160);
+}
+
+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 ret;
+ int i;
+
+ mutex_init(&qt2160->led_lock);
+
+ 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 = qt2160_led_set;
+ led->cdev.brightness = LED_OFF;
+ led->id = i;
+ led->qt2160 = qt2160;
+
+ INIT_WORK(&led->work, qt2160_led_work);
+
+ ret = led_classdev_register(&client->dev, &led->cdev);
+ if (ret < 0)
+ return ret;
+ }
+
+ /* 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;
+}
+
+static void qt2160_unregister_leds(struct qt2160_data *qt2160)
+{
+ int i;
+
+ for (i = 0; i < QT2160_NUM_LEDS_X; i++) {
+ led_classdev_unregister(&qt2160->leds[i].cdev);
+ cancel_work_sync(&qt2160->leds[i].work);
+ }
+}
+
+#else
+
+static inline int qt2160_register_leds(struct qt2160_data *qt2160)
+{
+ return 0;
+}
+
+static inline void qt2160_unregister_leds(struct qt2160_data *qt2160)
+{
+}
+
+#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,
+ const struct i2c_device_id *id)
+{
+ struct qt2160_data *qt2160;
+ struct input_dev *input;
+ int i;
+ int error;
+
+ /* Check functionality */
+ error = i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_BYTE);
+ if (!error) {
+ 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 = kzalloc(sizeof(struct qt2160_data), GFP_KERNEL);
+ input = input_allocate_device();
+ if (!qt2160 || !input) {
+ dev_err(&client->dev, "insufficient memory\n");
+ error = -ENOMEM;
+ goto err_free_mem;
+ }
+
+ qt2160->client = client;
+ qt2160->input = input;
+ INIT_DELAYED_WORK(&qt2160->dwork, qt2160_worker);
+ spin_lock_init(&qt2160->lock);
+
+ 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);
+
+ /* Calibrate device */
+ error = qt2160_write(client, QT2160_CMD_CALIBRATE, 1);
+ if (error) {
+ dev_err(&client->dev, "failed to calibrate device\n");
+ goto err_free_mem;
+ }
+
+ if (client->irq) {
+ error = request_irq(client->irq, qt2160_irq,
+ IRQF_TRIGGER_FALLING, "qt2160", qt2160);
+ if (error) {
+ dev_err(&client->dev,
+ "failed to allocate irq %d\n", client->irq);
+ goto err_free_mem;
+ }
+ }
+
+ error = qt2160_register_leds(qt2160);
+ if (error) {
+ dev_err(&client->dev, "Failed to register leds\n");
+ goto err_free_irq;
+ }
+
+ error = input_register_device(qt2160->input);
+ if (error) {
+ dev_err(&client->dev,
+ "Failed to register input device\n");
+ goto err_unregister_leds;
+ }
+
+ i2c_set_clientdata(client, qt2160);
+ qt2160_schedule_read(qt2160);
+
+ return 0;
+
+err_unregister_leds:
+ qt2160_unregister_leds(qt2160);
+err_free_irq:
+ if (client->irq)
+ free_irq(client->irq, qt2160);
+err_free_mem:
+ input_free_device(input);
+ kfree(qt2160);
+ return error;
+}
+
+static int qt2160_remove(struct i2c_client *client)
+{
+ struct qt2160_data *qt2160 = i2c_get_clientdata(client);
+
+ qt2160_unregister_leds(qt2160);
+
+ /* Release IRQ so no queue will be scheduled */
+ if (client->irq)
+ free_irq(client->irq, qt2160);
+
+ cancel_delayed_work_sync(&qt2160->dwork);
+
+ input_unregister_device(qt2160->input);
+ kfree(qt2160);
+
+ 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",
+ .owner = THIS_MODULE,
+ },
+
+ .id_table = qt2160_idtable,
+ .probe = qt2160_probe,
+ .remove = qt2160_remove,
+};
+
+module_i2c_driver(qt2160_driver);
+
+MODULE_AUTHOR("Raphael Derosso Pereira <raphaelpereira@gmail.com>");
+MODULE_DESCRIPTION("Driver for AT42QT2160 Touch Sensor");
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff