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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/input/keyboard/tca6416-keypad.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/input/keyboard/tca6416-keypad.c')
-rw-r--r-- | drivers/input/keyboard/tca6416-keypad.c | 312 |
1 files changed, 312 insertions, 0 deletions
diff --git a/drivers/input/keyboard/tca6416-keypad.c b/drivers/input/keyboard/tca6416-keypad.c new file mode 100644 index 0000000000..8af59ced1e --- /dev/null +++ b/drivers/input/keyboard/tca6416-keypad.c @@ -0,0 +1,312 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Driver for keys on TCA6416 I2C IO expander + * + * Copyright (C) 2010 Texas Instruments + * + * Author : Sriramakrishnan.A.G. <srk@ti.com> + */ + +#include <linux/types.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/workqueue.h> +#include <linux/gpio.h> +#include <linux/i2c.h> +#include <linux/input.h> +#include <linux/tca6416_keypad.h> + +#define TCA6416_INPUT 0 +#define TCA6416_OUTPUT 1 +#define TCA6416_INVERT 2 +#define TCA6416_DIRECTION 3 + +#define TCA6416_POLL_INTERVAL 100 /* msec */ + +static const struct i2c_device_id tca6416_id[] = { + { "tca6416-keys", 16, }, + { "tca6408-keys", 8, }, + { } +}; +MODULE_DEVICE_TABLE(i2c, tca6416_id); + +struct tca6416_drv_data { + struct input_dev *input; + struct tca6416_button data[]; +}; + +struct tca6416_keypad_chip { + uint16_t reg_output; + uint16_t reg_direction; + uint16_t reg_input; + + struct i2c_client *client; + struct input_dev *input; + int io_size; + int irqnum; + u16 pinmask; + bool use_polling; + struct tca6416_button buttons[]; +}; + +static int tca6416_write_reg(struct tca6416_keypad_chip *chip, int reg, u16 val) +{ + int error; + + error = chip->io_size > 8 ? + i2c_smbus_write_word_data(chip->client, reg << 1, val) : + i2c_smbus_write_byte_data(chip->client, reg, val); + if (error < 0) { + dev_err(&chip->client->dev, + "%s failed, reg: %d, val: %d, error: %d\n", + __func__, reg, val, error); + return error; + } + + return 0; +} + +static int tca6416_read_reg(struct tca6416_keypad_chip *chip, int reg, u16 *val) +{ + int retval; + + retval = chip->io_size > 8 ? + i2c_smbus_read_word_data(chip->client, reg << 1) : + i2c_smbus_read_byte_data(chip->client, reg); + if (retval < 0) { + dev_err(&chip->client->dev, "%s failed, reg: %d, error: %d\n", + __func__, reg, retval); + return retval; + } + + *val = (u16)retval; + return 0; +} + +static void tca6416_keys_scan(struct input_dev *input) +{ + struct tca6416_keypad_chip *chip = input_get_drvdata(input); + u16 reg_val, val; + int error, i, pin_index; + + error = tca6416_read_reg(chip, TCA6416_INPUT, ®_val); + if (error) + return; + + reg_val &= chip->pinmask; + + /* Figure out which lines have changed */ + val = reg_val ^ chip->reg_input; + chip->reg_input = reg_val; + + for (i = 0, pin_index = 0; i < 16; i++) { + if (val & (1 << i)) { + struct tca6416_button *button = &chip->buttons[pin_index]; + unsigned int type = button->type ?: EV_KEY; + int state = ((reg_val & (1 << i)) ? 1 : 0) + ^ button->active_low; + + input_event(input, type, button->code, !!state); + input_sync(input); + } + + if (chip->pinmask & (1 << i)) + pin_index++; + } +} + +/* + * This is threaded IRQ handler and this can (and will) sleep. + */ +static irqreturn_t tca6416_keys_isr(int irq, void *dev_id) +{ + tca6416_keys_scan(dev_id); + + return IRQ_HANDLED; +} + +static int tca6416_keys_open(struct input_dev *dev) +{ + struct tca6416_keypad_chip *chip = input_get_drvdata(dev); + + if (!chip->use_polling) { + /* Get initial device state in case it has switches */ + tca6416_keys_scan(dev); + enable_irq(chip->client->irq); + } + + return 0; +} + +static void tca6416_keys_close(struct input_dev *dev) +{ + struct tca6416_keypad_chip *chip = input_get_drvdata(dev); + + if (!chip->use_polling) + disable_irq(chip->client->irq); +} + +static int tca6416_setup_registers(struct tca6416_keypad_chip *chip) +{ + int error; + + error = tca6416_read_reg(chip, TCA6416_OUTPUT, &chip->reg_output); + if (error) + return error; + + error = tca6416_read_reg(chip, TCA6416_DIRECTION, &chip->reg_direction); + if (error) + return error; + + /* ensure that keypad pins are set to input */ + error = tca6416_write_reg(chip, TCA6416_DIRECTION, + chip->reg_direction | chip->pinmask); + if (error) + return error; + + error = tca6416_read_reg(chip, TCA6416_DIRECTION, &chip->reg_direction); + if (error) + return error; + + error = tca6416_read_reg(chip, TCA6416_INPUT, &chip->reg_input); + if (error) + return error; + + chip->reg_input &= chip->pinmask; + + return 0; +} + +static int tca6416_keypad_probe(struct i2c_client *client) +{ + const struct i2c_device_id *id = i2c_client_get_device_id(client); + struct tca6416_keys_platform_data *pdata; + struct tca6416_keypad_chip *chip; + struct input_dev *input; + int error; + int i; + + /* Check functionality */ + 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; + } + + pdata = dev_get_platdata(&client->dev); + if (!pdata) { + dev_dbg(&client->dev, "no platform data\n"); + return -EINVAL; + } + + chip = devm_kzalloc(&client->dev, + struct_size(chip, buttons, pdata->nbuttons), + GFP_KERNEL); + if (!chip) + return -ENOMEM; + + input = devm_input_allocate_device(&client->dev); + if (!input) + return -ENOMEM; + + chip->client = client; + chip->input = input; + chip->io_size = id->driver_data; + chip->pinmask = pdata->pinmask; + chip->use_polling = pdata->use_polling; + + input->phys = "tca6416-keys/input0"; + input->name = client->name; + + input->open = tca6416_keys_open; + input->close = tca6416_keys_close; + + input->id.bustype = BUS_HOST; + input->id.vendor = 0x0001; + input->id.product = 0x0001; + input->id.version = 0x0100; + + /* Enable auto repeat feature of Linux input subsystem */ + if (pdata->rep) + __set_bit(EV_REP, input->evbit); + + for (i = 0; i < pdata->nbuttons; i++) { + unsigned int type; + + chip->buttons[i] = pdata->buttons[i]; + type = (pdata->buttons[i].type) ?: EV_KEY; + input_set_capability(input, type, pdata->buttons[i].code); + } + + input_set_drvdata(input, chip); + + /* + * Initialize cached registers from their original values. + * we can't share this chip with another i2c master. + */ + error = tca6416_setup_registers(chip); + if (error) + return error; + + if (chip->use_polling) { + error = input_setup_polling(input, tca6416_keys_scan); + if (error) { + dev_err(&client->dev, "Failed to setup polling\n"); + return error; + } + + input_set_poll_interval(input, TCA6416_POLL_INTERVAL); + } else { + error = devm_request_threaded_irq(&client->dev, client->irq, + NULL, tca6416_keys_isr, + IRQF_TRIGGER_FALLING | + IRQF_ONESHOT | + IRQF_NO_AUTOEN, + "tca6416-keypad", input); + if (error) { + dev_dbg(&client->dev, + "Unable to claim irq %d; error %d\n", + client->irq, error); + return error; + } + } + + error = input_register_device(input); + if (error) { + dev_dbg(&client->dev, + "Unable to register input device, error: %d\n", error); + return error; + } + + i2c_set_clientdata(client, chip); + + return 0; +} + +static struct i2c_driver tca6416_keypad_driver = { + .driver = { + .name = "tca6416-keypad", + }, + .probe = tca6416_keypad_probe, + .id_table = tca6416_id, +}; + +static int __init tca6416_keypad_init(void) +{ + return i2c_add_driver(&tca6416_keypad_driver); +} + +subsys_initcall(tca6416_keypad_init); + +static void __exit tca6416_keypad_exit(void) +{ + i2c_del_driver(&tca6416_keypad_driver); +} +module_exit(tca6416_keypad_exit); + +MODULE_AUTHOR("Sriramakrishnan <srk@ti.com>"); +MODULE_DESCRIPTION("Keypad driver over tca6416 IO expander"); +MODULE_LICENSE("GPL"); |