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Diffstat (limited to 'drivers/input/keyboard/dlink-dir685-touchkeys.c')
-rw-r--r--drivers/input/keyboard/dlink-dir685-touchkeys.c155
1 files changed, 155 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 000000000000..88e321b76397
--- /dev/null
+++ b/drivers/input/keyboard/dlink-dir685-touchkeys.c
@@ -0,0 +1,155 @@
+/*
+ * 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 = "dlin-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");