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path: root/drivers/input/touchscreen/touchit213.c
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Diffstat (limited to 'drivers/input/touchscreen/touchit213.c')
-rw-r--r--drivers/input/touchscreen/touchit213.c214
1 files changed, 214 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/touchit213.c b/drivers/input/touchscreen/touchit213.c
new file mode 100644
index 0000000000..fb49687da4
--- /dev/null
+++ b/drivers/input/touchscreen/touchit213.c
@@ -0,0 +1,214 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Sahara TouchIT-213 serial touchscreen driver
+ *
+ * Copyright (c) 2007-2008 Claudio Nieder <private@claudio.ch>
+ *
+ * Based on Touchright driver (drivers/input/touchscreen/touchright.c)
+ * Copyright (c) 2006 Rick Koch <n1gp@hotmail.com>
+ * Copyright (c) 2004 Vojtech Pavlik
+ * and Dan Streetman <ddstreet@ieee.org>
+ */
+
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/serio.h>
+
+#define DRIVER_DESC "Sahara TouchIT-213 serial touchscreen driver"
+
+MODULE_AUTHOR("Claudio Nieder <private@claudio.ch>");
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+
+/*
+ * Definitions & global arrays.
+ */
+
+/*
+ * Data is received through COM1 at 9600bit/s,8bit,no parity in packets
+ * of 5 byte each.
+ *
+ * +--------+ +--------+ +--------+ +--------+ +--------+
+ * |1000000p| |0xxxxxxx| |0xxxxxxx| |0yyyyyyy| |0yyyyyyy|
+ * +--------+ +--------+ +--------+ +--------+ +--------+
+ * MSB LSB MSB LSB
+ *
+ * The value of p is 1 as long as the screen is touched and 0 when
+ * reporting the location where touching stopped, e.g. where the pen was
+ * lifted from the screen.
+ *
+ * When holding the screen in landscape mode as the BIOS text output is
+ * presented, x is the horizontal axis with values growing from left to
+ * right and y is the vertical axis with values growing from top to
+ * bottom.
+ *
+ * When holding the screen in portrait mode with the Sahara logo in its
+ * correct position, x ist the vertical axis with values growing from
+ * top to bottom and y is the horizontal axis with values growing from
+ * right to left.
+ */
+
+#define T213_FORMAT_TOUCH_BIT 0x01
+#define T213_FORMAT_STATUS_BYTE 0x80
+#define T213_FORMAT_STATUS_MASK ~T213_FORMAT_TOUCH_BIT
+
+/*
+ * On my Sahara Touch-IT 213 I have observed x values from 0 to 0x7f0
+ * and y values from 0x1d to 0x7e9, so the actual measurement is
+ * probably done with an 11 bit precision.
+ */
+#define T213_MIN_XC 0
+#define T213_MAX_XC 0x07ff
+#define T213_MIN_YC 0
+#define T213_MAX_YC 0x07ff
+
+/*
+ * Per-touchscreen data.
+ */
+
+struct touchit213 {
+ struct input_dev *dev;
+ struct serio *serio;
+ int idx;
+ unsigned char csum;
+ unsigned char data[5];
+ char phys[32];
+};
+
+static irqreturn_t touchit213_interrupt(struct serio *serio,
+ unsigned char data, unsigned int flags)
+{
+ struct touchit213 *touchit213 = serio_get_drvdata(serio);
+ struct input_dev *dev = touchit213->dev;
+
+ touchit213->data[touchit213->idx] = data;
+
+ switch (touchit213->idx++) {
+ case 0:
+ if ((touchit213->data[0] & T213_FORMAT_STATUS_MASK) !=
+ T213_FORMAT_STATUS_BYTE) {
+ pr_debug("unsynchronized data: 0x%02x\n", data);
+ touchit213->idx = 0;
+ }
+ break;
+
+ case 4:
+ touchit213->idx = 0;
+ input_report_abs(dev, ABS_X,
+ (touchit213->data[1] << 7) | touchit213->data[2]);
+ input_report_abs(dev, ABS_Y,
+ (touchit213->data[3] << 7) | touchit213->data[4]);
+ input_report_key(dev, BTN_TOUCH,
+ touchit213->data[0] & T213_FORMAT_TOUCH_BIT);
+ input_sync(dev);
+ break;
+ }
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * touchit213_disconnect() is the opposite of touchit213_connect()
+ */
+
+static void touchit213_disconnect(struct serio *serio)
+{
+ struct touchit213 *touchit213 = serio_get_drvdata(serio);
+
+ input_get_device(touchit213->dev);
+ input_unregister_device(touchit213->dev);
+ serio_close(serio);
+ serio_set_drvdata(serio, NULL);
+ input_put_device(touchit213->dev);
+ kfree(touchit213);
+}
+
+/*
+ * touchit213_connect() is the routine that is called when someone adds a
+ * new serio device that supports the Touchright protocol and registers it as
+ * an input device.
+ */
+
+static int touchit213_connect(struct serio *serio, struct serio_driver *drv)
+{
+ struct touchit213 *touchit213;
+ struct input_dev *input_dev;
+ int err;
+
+ touchit213 = kzalloc(sizeof(struct touchit213), GFP_KERNEL);
+ input_dev = input_allocate_device();
+ if (!touchit213 || !input_dev) {
+ err = -ENOMEM;
+ goto fail1;
+ }
+
+ touchit213->serio = serio;
+ touchit213->dev = input_dev;
+ snprintf(touchit213->phys, sizeof(touchit213->phys),
+ "%s/input0", serio->phys);
+
+ input_dev->name = "Sahara Touch-iT213 Serial TouchScreen";
+ input_dev->phys = touchit213->phys;
+ input_dev->id.bustype = BUS_RS232;
+ input_dev->id.vendor = SERIO_TOUCHIT213;
+ input_dev->id.product = 0;
+ input_dev->id.version = 0x0100;
+ input_dev->dev.parent = &serio->dev;
+ input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+ input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+ input_set_abs_params(touchit213->dev, ABS_X,
+ T213_MIN_XC, T213_MAX_XC, 0, 0);
+ input_set_abs_params(touchit213->dev, ABS_Y,
+ T213_MIN_YC, T213_MAX_YC, 0, 0);
+
+ serio_set_drvdata(serio, touchit213);
+
+ err = serio_open(serio, drv);
+ if (err)
+ goto fail2;
+
+ err = input_register_device(touchit213->dev);
+ if (err)
+ goto fail3;
+
+ return 0;
+
+ fail3: serio_close(serio);
+ fail2: serio_set_drvdata(serio, NULL);
+ fail1: input_free_device(input_dev);
+ kfree(touchit213);
+ return err;
+}
+
+/*
+ * The serio driver structure.
+ */
+
+static const struct serio_device_id touchit213_serio_ids[] = {
+ {
+ .type = SERIO_RS232,
+ .proto = SERIO_TOUCHIT213,
+ .id = SERIO_ANY,
+ .extra = SERIO_ANY,
+ },
+ { 0 }
+};
+
+MODULE_DEVICE_TABLE(serio, touchit213_serio_ids);
+
+static struct serio_driver touchit213_drv = {
+ .driver = {
+ .name = "touchit213",
+ },
+ .description = DRIVER_DESC,
+ .id_table = touchit213_serio_ids,
+ .interrupt = touchit213_interrupt,
+ .connect = touchit213_connect,
+ .disconnect = touchit213_disconnect,
+};
+
+module_serio_driver(touchit213_drv);