// SPDX-License-Identifier: GPL-2.0-or-later /* * qt2160.c - Atmel AT42QT2160 Touch Sense Controller * * Copyright (C) 2009 Raphael Derosso Pereira */ #include #include #include #include #include #include #include #include #include #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 ret; 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; 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); } #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) { 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 = 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; 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"); goto err_free_mem; } if (client->irq) { error = request_threaded_irq(client->irq, NULL, qt2160_irq, IRQF_TRIGGER_LOW | IRQF_ONESHOT, "qt2160", input); if (error) { dev_err(&client->dev, "failed to allocate irq %d\n", client->irq); goto err_free_mem; } } else { error = input_setup_polling(input, qt2160_get_key_matrix); if (error) { dev_err(&client->dev, "Failed to setup polling\n"); goto err_free_mem; } input_set_poll_interval(input, QT2160_CYCLE_INTERVAL); } 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); 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 void 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); input_unregister_device(qt2160->input); kfree(qt2160); } 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 "); MODULE_DESCRIPTION("Driver for AT42QT2160 Touch Sensor"); MODULE_LICENSE("GPL");