input: add qt1070 touch keyboard support

use irq pin as the pin is asserted untill we clear it
This will allow to do not poll on i2c which slow down barebox

If no irq_pin is provided fall back on i2c polling

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

3 files changed, 305 insertions, 0 deletions

diff --git a/drivers/input/Kconfig b/drivers/input/Kconfig
index 15979a2761..846483c794 100644
--- a/drivers/input/Kconfig
+++ b/drivers/input/Kconfig
@@ -30,4 +30,12 @@ config KEYBOARD_IMX_KEYPAD
 	  setup logic must also provide a 'matrix_keymap_data' structure,
 	  defining the used keys.
 
+config KEYBOARD_QT1070
+	tristate "Atmel AT42QT1070 Touch Sensor Chip"
+	depends on I2C
+	select POLLER
+	help
+	  Say Y here if you want to use Atmel AT42QT1070 QTouch
+	  Sensor chip as input device.
+
 endmenu
diff --git a/drivers/input/Makefile b/drivers/input/Makefile
index 3d105cc8b0..d042980b15 100644
--- a/drivers/input/Makefile
+++ b/drivers/input/Makefile
@@ -1,2 +1,3 @@
 obj-$(CONFIG_KEYBOARD_GPIO) += gpio_keys.o
 obj-$(CONFIG_KEYBOARD_IMX_KEYPAD) += imx_keypad.o
+obj-$(CONFIG_KEYBOARD_QT1070) += qt1070.o
diff --git a/drivers/input/qt1070.c b/drivers/input/qt1070.c
new file mode 100644
index 0000000000..c66189e9c7
--- /dev/null
+++ b/drivers/input/qt1070.c
@@ -0,0 +1,296 @@
+/*
+ * Copyright (C) 2012 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
+ *
+ * Under GPLv2
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <init.h>
+#include <clock.h>
+#include <poller.h>
+#include <kfifo.h>
+#include <i2c/i2c.h>
+#include <malloc.h>
+#include <readkey.h>
+#include <input/qt1070.h>
+#include <gpio.h>
+
+#define QT1070_CHIP_ID		0x2e
+
+#define QT1070_READ_CHIP_ID	0x00
+#define QT1070_FW_VERSION	0x01
+#define QT1070_DET_STATUS	0x02
+#define QT1070_KEY_STATUS	0x03
+
+/* Calibrate */
+#define QT1070_CALIBRATE_CMD	0x38
+#define QT1070_CAL_TIME		200
+
+/* Reset */
+#define QT1070_RESET		0x39
+#define QT1070_RESET_TIME	255
+
+static int default_code[QT1070_NB_BUTTONS] = {
+	KEY_ENTER, KEY_HOME, KEY_UP, KEY_DOWN,
+	KEY_RIGHT, KEY_LEFT, KEY_CLEAR_SCREEN };
+
+struct qt1070_data {
+	int code[QT1070_NB_BUTTONS];
+
+	int irq_pin;
+
+	u64 start;
+
+	/* optional */
+	int fifo_size;
+
+	struct i2c_client *client;
+	u8 button_state[QT1070_NB_BUTTONS];
+	u8 previous_state;
+
+	struct kfifo *recv_fifo;
+	struct poller_struct poller;
+	struct console_device cdev;
+};
+
+static inline struct qt1070_data *
+poller_to_qt_data(struct poller_struct *poller)
+{
+	return container_of(poller, struct qt1070_data, poller);
+}
+
+static inline struct qt1070_data *
+cdev_to_qt_data(struct console_device *cdev)
+{
+	return container_of(cdev, struct qt1070_data, cdev);
+}
+
+static bool qt1070_read(struct qt1070_data *data, u8 reg, u8 *val)
+{
+	int ret;
+
+	ret = i2c_read_reg(data->client, reg, val, 1);
+
+	if (ret < 0)
+		return ret;
+	if (ret != 1)
+		return -EIO;
+	return 0;
+}
+
+static bool qt1070_write(struct qt1070_data *data, u8 reg, const u8 val)
+{
+	int ret;
+
+	ret = i2c_write_reg(data->client, reg, &val, 1);
+	if (ret < 0)
+		return ret;
+	if (ret != 1)
+		return -EIO;
+	return 0;
+}
+
+static void qt1070_poller(struct poller_struct *poller)
+{
+	struct qt1070_data *data = poller_to_qt_data(poller);
+	int i;
+	u8 buf, bt;
+	u8 mask = 0x1;
+
+	if (gpio_is_valid(data->irq_pin)) {
+		/* active low */
+		if (gpio_get_value(data->irq_pin))
+			return;
+	}
+
+	qt1070_read(data, QT1070_DET_STATUS, &buf);
+
+	if (qt1070_read(data, QT1070_KEY_STATUS, &buf))
+		return;
+
+	if (!buf & !data->previous_state)
+		return;
+
+	for (i = 0; i < QT1070_NB_BUTTONS; i++) {
+		bt = buf & mask;
+
+		if (!bt && data->button_state[i]) {
+			dev_dbg(data->cdev.dev, "release key(%d) as %d\n", i, data->code[i]);
+			kfifo_put(data->recv_fifo, (u_char*)&data->code[i], sizeof(int));
+		} else if (bt) {
+			dev_dbg(data->cdev.dev, "pressed key(%d) as %d\n", i, data->code[i]);
+		}
+
+		data->button_state[i] = bt;
+		mask <<= 1;
+	}
+
+	data->previous_state = buf;
+}
+
+static void qt1070_reset_poller(struct poller_struct *poller)
+{
+	struct qt1070_data *data = poller_to_qt_data(poller);
+	u8 buf;
+
+	if (!is_timeout_non_interruptible(data->start, QT1070_RESET_TIME * MSECOND))
+		return;
+
+	/* clear the status */
+	qt1070_read(data, QT1070_DET_STATUS, &buf);
+
+	poller->func = qt1070_poller;
+}
+
+static void qt1070_calibrate_poller(struct poller_struct *poller)
+{
+	struct qt1070_data *data = poller_to_qt_data(poller);
+	int ret;
+
+	if (!is_timeout_non_interruptible(data->start, QT1070_CAL_TIME * MSECOND))
+		return;
+
+	/* Soft reset */
+	ret = qt1070_write(data, QT1070_RESET, 1);
+	if (ret) {
+		dev_err(data->cdev.dev, "can not reset the chip (%d)\n", ret);
+		poller_unregister(poller);
+		return;
+	}
+	data->start = get_time_ns();
+
+	poller->func = qt1070_reset_poller;
+}
+
+static int qt1070_tstc(struct console_device *cdev)
+{
+	struct qt1070_data *data = cdev_to_qt_data(cdev);
+
+	return (kfifo_len(data->recv_fifo) == 0) ? 0 : 1;
+}
+
+static int qt1070_getc(struct console_device *cdev)
+{
+	int code = 0;
+	struct qt1070_data *data = cdev_to_qt_data(cdev);
+
+	kfifo_get(data->recv_fifo, (u_char*)&code, sizeof(int));
+	return code;
+}
+
+static int qt1070_pdata_init(struct device_d *dev, struct qt1070_data *data)
+{
+	struct qt1070_platform_data *pdata = dev->platform_data;
+	int ret;
+
+	if (!pdata)
+		return 0;
+
+	if (pdata->nb_code)
+		memcpy(data->code, pdata->code, sizeof(int) * pdata->nb_code);
+
+	if (!gpio_is_valid(pdata->irq_pin))
+		return 0;
+
+	ret = gpio_request(pdata->irq_pin, "qt1070");
+	if (ret)
+		return ret;
+
+	ret = gpio_direction_input(pdata->irq_pin);
+	if (ret)
+		goto err;
+
+	data->irq_pin = pdata->irq_pin;
+
+	return 0;
+err:
+	gpio_free(pdata->irq_pin);
+	return ret;
+}
+
+static int qt1070_probe(struct device_d *dev)
+{
+	struct console_device *cdev;
+	struct qt1070_data *data;
+	u8 fw_version, chip_id;
+	int ret;
+	char buf[6];
+
+	data = xzalloc(sizeof(*data));
+	data->client = to_i2c_client(dev);
+	data->irq_pin = -EINVAL;
+
+	ret = qt1070_read(data, QT1070_READ_CHIP_ID, &chip_id);
+	if (ret) {
+		dev_err(dev, "can not read chip id (%d)\n", ret);
+		goto err;
+	}
+
+	if (chip_id != QT1070_CHIP_ID) {
+		dev_err(dev, "unsupported id 0x%x\n", chip_id);
+		ret = -ENXIO;
+		goto err;
+	}
+
+	ret = qt1070_read(data, QT1070_FW_VERSION, &fw_version);
+	if (ret) {
+		dev_err(dev, "can not read firmware version (%d)\n", ret);
+		goto err;
+	}
+
+	sprintf(buf, "0x%x", fw_version);
+	dev_add_param_fixed(dev, "fw_version", buf);
+	sprintf(buf, "0x%x", chip_id);
+	dev_add_param_fixed(dev, "chip_ip", buf);
+
+	ret = qt1070_pdata_init(dev, data);
+	if (ret) {
+		dev_err(dev, "can not get pdata (%d)\n", ret);
+		goto err;
+	}
+
+	/* Calibrate device */
+	ret = qt1070_write(data, QT1070_CALIBRATE_CMD, 1);
+	if (ret) {
+		dev_err(dev, "can not calibrate the chip (%d)\n", ret);
+		goto err;
+	}
+	data->start = get_time_ns();
+
+	memcpy(data->code, default_code, sizeof(int) * ARRAY_SIZE(default_code));
+
+	data->fifo_size = 50;
+	data->recv_fifo = kfifo_alloc(data->fifo_size);
+
+	data->poller.func = qt1070_calibrate_poller;
+
+	cdev = &data->cdev;
+	cdev->dev = dev;
+	cdev->f_caps = CONSOLE_STDIN;
+	cdev->tstc = qt1070_tstc;
+	cdev->getc = qt1070_getc;
+
+	console_register(&data->cdev);
+
+	ret = poller_register(&data->poller);
+	if (ret)
+		goto err;
+
+	return 0;
+err:
+	free(data);
+	return ret;
+}
+
+static struct driver_d qt1070_driver = {
+	.name	= "qt1070",
+	.probe	= qt1070_probe,
+};
+
+static int qt1070_init(void)
+{
+	i2c_register_driver(&qt1070_driver);
+	return 0;
+}
+device_initcall(qt1070_init);