Input: add a driver for TSC-40 serial touchscreen
This patch adds the TSC-40 serial touchscreen driver and should be
compatible with TSC-10 and TSC-25.
The driver was written by Linutronix on behalf of Bachmann electronic GmbH.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/touchscreen/tsc40.c b/drivers/input/touchscreen/tsc40.c
new file mode 100644
index 0000000..29d5ed4
--- /dev/null
+++ b/drivers/input/touchscreen/tsc40.c
@@ -0,0 +1,184 @@
+/*
+ * TSC-40 serial touchscreen driver. It should be compatible with
+ * TSC-10 and 25.
+ *
+ * Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+ * License: GPLv2 as published by the FSF.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/serio.h>
+#include <linux/init.h>
+
+#define PACKET_LENGTH 5
+struct tsc_ser {
+ struct input_dev *dev;
+ struct serio *serio;
+ u32 idx;
+ unsigned char data[PACKET_LENGTH];
+ char phys[32];
+};
+
+static void tsc_process_data(struct tsc_ser *ptsc)
+{
+ struct input_dev *dev = ptsc->dev;
+ u8 *data = ptsc->data;
+ u32 x;
+ u32 y;
+
+ x = ((data[1] & 0x03) << 8) | data[2];
+ y = ((data[3] & 0x03) << 8) | data[4];
+
+ input_report_abs(dev, ABS_X, x);
+ input_report_abs(dev, ABS_Y, y);
+ input_report_key(dev, BTN_TOUCH, 1);
+
+ input_sync(dev);
+}
+
+static irqreturn_t tsc_interrupt(struct serio *serio,
+ unsigned char data, unsigned int flags)
+{
+ struct tsc_ser *ptsc = serio_get_drvdata(serio);
+ struct input_dev *dev = ptsc->dev;
+
+ ptsc->data[ptsc->idx] = data;
+ switch (ptsc->idx++) {
+ case 0:
+ if (unlikely((data & 0x3e) != 0x10)) {
+ dev_dbg(&serio->dev,
+ "unsynchronized packet start (0x%02x)\n", data);
+ ptsc->idx = 0;
+ } else if (!(data & 0x01)) {
+ input_report_key(dev, BTN_TOUCH, 0);
+ input_sync(dev);
+ ptsc->idx = 0;
+ }
+ break;
+
+ case 1:
+ case 3:
+ if (unlikely(data & 0xfc)) {
+ dev_dbg(&serio->dev,
+ "unsynchronized data 0x%02x at offset %d\n",
+ data, ptsc->idx - 1);
+ ptsc->idx = 0;
+ }
+ break;
+
+ case 4:
+ tsc_process_data(ptsc);
+ ptsc->idx = 0;
+ break;
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int tsc_connect(struct serio *serio, struct serio_driver *drv)
+{
+ struct tsc_ser *ptsc;
+ struct input_dev *input_dev;
+ int error;
+
+ ptsc = kzalloc(sizeof(struct tsc_ser), GFP_KERNEL);
+ input_dev = input_allocate_device();
+ if (!ptsc || !input_dev) {
+ error = -ENOMEM;
+ goto fail1;
+ }
+
+ ptsc->serio = serio;
+ ptsc->dev = input_dev;
+ snprintf(ptsc->phys, sizeof(ptsc->phys), "%s/input0", serio->phys);
+
+ input_dev->name = "TSC-10/25/40 Serial TouchScreen";
+ input_dev->phys = ptsc->phys;
+ input_dev->id.bustype = BUS_RS232;
+ input_dev->id.vendor = SERIO_TSC40;
+ input_dev->id.product = 40;
+ input_dev->id.version = 0x0001;
+ input_dev->dev.parent = &serio->dev;
+
+ input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+ __set_bit(BTN_TOUCH, input_dev->keybit);
+ input_set_abs_params(ptsc->dev, ABS_X, 0, 0x3ff, 0, 0);
+ input_set_abs_params(ptsc->dev, ABS_Y, 0, 0x3ff, 0, 0);
+ input_set_abs_params(ptsc->dev, ABS_PRESSURE, 0, 0, 0, 0);
+
+ serio_set_drvdata(serio, ptsc);
+
+ error = serio_open(serio, drv);
+ if (error)
+ goto fail2;
+
+ error = input_register_device(ptsc->dev);
+ if (error)
+ goto fail3;
+
+ return 0;
+
+fail3:
+ serio_close(serio);
+fail2:
+ serio_set_drvdata(serio, NULL);
+fail1:
+ input_free_device(input_dev);
+ kfree(ptsc);
+ return error;
+}
+
+static void tsc_disconnect(struct serio *serio)
+{
+ struct tsc_ser *ptsc = serio_get_drvdata(serio);
+
+ serio_close(serio);
+
+ input_unregister_device(ptsc->dev);
+ kfree(ptsc);
+
+ serio_set_drvdata(serio, NULL);
+}
+
+static struct serio_device_id tsc_serio_ids[] = {
+ {
+ .type = SERIO_RS232,
+ .proto = SERIO_TSC40,
+ .id = SERIO_ANY,
+ .extra = SERIO_ANY,
+ },
+ { 0 }
+};
+MODULE_DEVICE_TABLE(serio, tsc_serio_ids);
+
+#define DRIVER_DESC "TSC-10/25/40 serial touchscreen driver"
+
+static struct serio_driver tsc_drv = {
+ .driver = {
+ .name = "tsc40",
+ },
+ .description = DRIVER_DESC,
+ .id_table = tsc_serio_ids,
+ .interrupt = tsc_interrupt,
+ .connect = tsc_connect,
+ .disconnect = tsc_disconnect,
+};
+
+static int __init tsc_ser_init(void)
+{
+ return serio_register_driver(&tsc_drv);
+}
+module_init(tsc_ser_init);
+
+static void __exit tsc_exit(void)
+{
+ serio_unregister_driver(&tsc_drv);
+}
+module_exit(tsc_exit);
+
+MODULE_AUTHOR("Sebastian Andrzej Siewior <bigeasy@linutronix.de>");
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL v2");