diff options
Diffstat (limited to 'drivers/input/keyboard/qt2160.c')
| -rw-r--r-- | drivers/input/keyboard/qt2160.c | 397 |
1 files changed, 397 insertions, 0 deletions
diff --git a/drivers/input/keyboard/qt2160.c b/drivers/input/keyboard/qt2160.c new file mode 100644 index 000000000000..191cc51d6cf8 --- /dev/null +++ b/drivers/input/keyboard/qt2160.c @@ -0,0 +1,397 @@ +/* + * 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/init.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_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, +}; + +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; +}; + +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); + + __cancel_delayed_work(&qt2160->dwork); + schedule_delayed_work(&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 __devinit 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 __devinit qt2160_write(struct i2c_client *client, u8 reg, u8 data) +{ + int error; + + error = i2c_smbus_write_byte(client, reg); + if (error) { + dev_err(&client->dev, + "couldn't send request. Returned %d\n", error); + return error; + } + + error = i2c_smbus_write_byte(client, data); + if (error) { + dev_err(&client->dev, + "couldn't write data. Returned %d\n", error); + return error; + } + + return error; +} + + +static bool __devinit 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 __devinit 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 = input_register_device(qt2160->input); + if (error) { + dev_err(&client->dev, + "Failed to register input device\n"); + goto err_free_irq; + } + + i2c_set_clientdata(client, qt2160); + qt2160_schedule_read(qt2160); + + return 0; + +err_free_irq: + if (client->irq) + free_irq(client->irq, qt2160); +err_free_mem: + input_free_device(input); + kfree(qt2160); + return error; +} + +static int __devexit qt2160_remove(struct i2c_client *client) +{ + struct qt2160_data *qt2160 = i2c_get_clientdata(client); + + /* 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); + + i2c_set_clientdata(client, NULL); + return 0; +} + +static 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 = __devexit_p(qt2160_remove), +}; + +static int __init qt2160_init(void) +{ + return i2c_add_driver(&qt2160_driver); +} +module_init(qt2160_init); + +static void __exit qt2160_cleanup(void) +{ + i2c_del_driver(&qt2160_driver); +} +module_exit(qt2160_cleanup); + +MODULE_AUTHOR("Raphael Derosso Pereira <raphaelpereira@gmail.com>"); +MODULE_DESCRIPTION("Driver for AT42QT2160 Touch Sensor"); +MODULE_LICENSE("GPL"); |