diff options
Diffstat (limited to 'drivers/input/keyboard/dlink-dir685-touchkeys.c')
| -rw-r--r-- | drivers/input/keyboard/dlink-dir685-touchkeys.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/drivers/input/keyboard/dlink-dir685-touchkeys.c b/drivers/input/keyboard/dlink-dir685-touchkeys.c new file mode 100644 index 000000000..a69dcc3bd --- /dev/null +++ b/drivers/input/keyboard/dlink-dir685-touchkeys.c @@ -0,0 +1,156 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * D-Link DIR-685 router I2C-based Touchkeys input driver + * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org> + * + * This is a one-off touchkey controller based on the Cypress Semiconductor + * CY8C214 MCU with some firmware in its internal 8KB flash. The circuit + * board inside the router is named E119921 + */ + +#include <linux/module.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/input.h> +#include <linux/slab.h> +#include <linux/bitops.h> + +struct dir685_touchkeys { + struct device *dev; + struct i2c_client *client; + struct input_dev *input; + unsigned long cur_key; + u16 codes[7]; +}; + +static irqreturn_t dir685_tk_irq_thread(int irq, void *data) +{ + struct dir685_touchkeys *tk = data; + const int num_bits = min_t(int, ARRAY_SIZE(tk->codes), 16); + unsigned long changed; + u8 buf[6]; + unsigned long key; + int i; + int err; + + memset(buf, 0, sizeof(buf)); + err = i2c_master_recv(tk->client, buf, sizeof(buf)); + if (err != sizeof(buf)) { + dev_err(tk->dev, "short read %d\n", err); + return IRQ_HANDLED; + } + + dev_dbg(tk->dev, "IN: %*ph\n", (int)sizeof(buf), buf); + key = be16_to_cpup((__be16 *) &buf[4]); + + /* Figure out if any bits went high or low since last message */ + changed = tk->cur_key ^ key; + for_each_set_bit(i, &changed, num_bits) { + dev_dbg(tk->dev, "key %d is %s\n", i, + test_bit(i, &key) ? "down" : "up"); + input_report_key(tk->input, tk->codes[i], test_bit(i, &key)); + } + + /* Store currently down keys */ + tk->cur_key = key; + input_sync(tk->input); + + return IRQ_HANDLED; +} + +static int dir685_tk_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct dir685_touchkeys *tk; + struct device *dev = &client->dev; + u8 bl_data[] = { 0xa7, 0x40 }; + int err; + int i; + + tk = devm_kzalloc(&client->dev, sizeof(*tk), GFP_KERNEL); + if (!tk) + return -ENOMEM; + + tk->input = devm_input_allocate_device(dev); + if (!tk->input) + return -ENOMEM; + + tk->client = client; + tk->dev = dev; + + tk->input->keycodesize = sizeof(u16); + tk->input->keycodemax = ARRAY_SIZE(tk->codes); + tk->input->keycode = tk->codes; + tk->codes[0] = KEY_UP; + tk->codes[1] = KEY_DOWN; + tk->codes[2] = KEY_LEFT; + tk->codes[3] = KEY_RIGHT; + tk->codes[4] = KEY_ENTER; + tk->codes[5] = KEY_WPS_BUTTON; + /* + * This key appears in the vendor driver, but I have + * not been able to activate it. + */ + tk->codes[6] = KEY_RESERVED; + + __set_bit(EV_KEY, tk->input->evbit); + for (i = 0; i < ARRAY_SIZE(tk->codes); i++) + __set_bit(tk->codes[i], tk->input->keybit); + __clear_bit(KEY_RESERVED, tk->input->keybit); + + tk->input->name = "D-Link DIR-685 touchkeys"; + tk->input->id.bustype = BUS_I2C; + + err = input_register_device(tk->input); + if (err) + return err; + + /* Set the brightness to max level */ + err = i2c_master_send(client, bl_data, sizeof(bl_data)); + if (err != sizeof(bl_data)) + dev_warn(tk->dev, "error setting brightness level\n"); + + if (!client->irq) { + dev_err(dev, "no IRQ on the I2C device\n"); + return -ENODEV; + } + err = devm_request_threaded_irq(dev, client->irq, + NULL, dir685_tk_irq_thread, + IRQF_ONESHOT, + "dir685-tk", tk); + if (err) { + dev_err(dev, "can't request IRQ\n"); + return err; + } + + return 0; +} + +static const struct i2c_device_id dir685_tk_id[] = { + { "dir685tk", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, dir685_tk_id); + +#ifdef CONFIG_OF +static const struct of_device_id dir685_tk_of_match[] = { + { .compatible = "dlink,dir685-touchkeys" }, + {}, +}; +MODULE_DEVICE_TABLE(of, dir685_tk_of_match); +#endif + +static struct i2c_driver dir685_tk_i2c_driver = { + .driver = { + .name = "dlink-dir685-touchkeys", + .of_match_table = of_match_ptr(dir685_tk_of_match), + }, + .probe = dir685_tk_probe, + .id_table = dir685_tk_id, +}; +module_i2c_driver(dir685_tk_i2c_driver); + +MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>"); +MODULE_DESCRIPTION("D-Link DIR-685 touchkeys driver"); +MODULE_LICENSE("GPL"); |