cregit-Linux how code gets into the kernel

Release 4.7 drivers/input/keyboard/qt2160.c

/*
 *  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); }

Contributors

PersonTokensPropCommitsCommitProp
javier martinjavier martin177100.00%1100.00%
Total177100.00%1100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
javier martinjavier martin44100.00%1100.00%
Total44100.00%1100.00%

#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; }

Contributors

PersonTokensPropCommitsCommitProp
raphael derosso pereiraraphael derosso pereira195100.00%1100.00%
Total195100.00%1100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
raphael derosso pereiraraphael derosso pereira198100.00%1100.00%
Total198100.00%1100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
raphael derosso pereiraraphael derosso pereira5694.92%150.00%
tejun heotejun heo35.08%150.00%
Total59100.00%2100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
raphael derosso pereiraraphael derosso pereira37100.00%1100.00%
Total37100.00%1100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
raphael derosso pereiraraphael derosso pereira51100.00%1100.00%
Total51100.00%1100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
raphael derosso pereiraraphael derosso pereira80100.00%1100.00%
Total80100.00%1100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
raphael derosso pereiraraphael derosso pereira4484.62%150.00%
javier martinjavier martin815.38%150.00%
Total52100.00%2100.00%

#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; }

Contributors

PersonTokensPropCommitsCommitProp
javier martinjavier martin183100.00%1100.00%
Total183100.00%1100.00%


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); } }

Contributors

PersonTokensPropCommitsCommitProp
javier martinjavier martin55100.00%1100.00%
Total55100.00%1100.00%

#else
static inline int qt2160_register_leds(struct qt2160_data *qt2160) { return 0; }

Contributors

PersonTokensPropCommitsCommitProp
javier martinjavier martin15100.00%1100.00%
Total15100.00%1100.00%


static inline void qt2160_unregister_leds(struct qt2160_data *qt2160) { }

Contributors

PersonTokensPropCommitsCommitProp
javier martinjavier martin11100.00%1100.00%
Total11100.00%1100.00%

#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; }

Contributors

PersonTokensPropCommitsCommitProp
raphael derosso pereiraraphael derosso pereira136100.00%1100.00%
Total136100.00%1100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
raphael derosso pereiraraphael derosso pereira43292.70%150.00%
javier martinjavier martin347.30%150.00%
Total466100.00%2100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
raphael derosso pereiraraphael derosso pereira6092.31%150.00%
javier martinjavier martin57.69%150.00%
Total65100.00%2100.00%

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, .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");

Overall Contributors

PersonTokensPropCommitsCommitProp
raphael derosso pereiraraphael derosso pereira150869.88%116.67%
javier martinjavier martin64529.89%233.33%
tejun heotejun heo30.14%116.67%
marton nemethmarton nemeth10.05%116.67%
axel linaxel lin10.05%116.67%
Total2158100.00%6100.00%
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
{% endraw %}