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path: root/drivers/input/touchscreen/fujitsu_ts.c
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Diffstat (limited to 'drivers/input/touchscreen/fujitsu_ts.c')
-rw-r--r--drivers/input/touchscreen/fujitsu_ts.c173
1 files changed, 173 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/fujitsu_ts.c b/drivers/input/touchscreen/fujitsu_ts.c
new file mode 100644
index 0000000000..3b0b8fccc3
--- /dev/null
+++ b/drivers/input/touchscreen/fujitsu_ts.c
@@ -0,0 +1,173 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Fujitsu serial touchscreen driver
+ *
+ * Copyright (c) Dmitry Torokhov <dtor@mail.ru>
+ */
+
+
+#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 "Fujitsu serial touchscreen driver"
+
+MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+
+#define FUJITSU_LENGTH 5
+
+/*
+ * Per-touchscreen data.
+ */
+struct fujitsu {
+ struct input_dev *dev;
+ struct serio *serio;
+ int idx;
+ unsigned char data[FUJITSU_LENGTH];
+ char phys[32];
+};
+
+/*
+ * Decode serial data (5 bytes per packet)
+ * First byte
+ * 1 C 0 0 R S S S
+ * Where C is 1 while in calibration mode (which we don't use)
+ * R is 1 when no coordinate corection was done.
+ * S are button state
+ */
+static irqreturn_t fujitsu_interrupt(struct serio *serio,
+ unsigned char data, unsigned int flags)
+{
+ struct fujitsu *fujitsu = serio_get_drvdata(serio);
+ struct input_dev *dev = fujitsu->dev;
+
+ if (fujitsu->idx == 0) {
+ /* resync skip until start of frame */
+ if ((data & 0xf0) != 0x80)
+ return IRQ_HANDLED;
+ } else {
+ /* resync skip garbage */
+ if (data & 0x80) {
+ fujitsu->idx = 0;
+ return IRQ_HANDLED;
+ }
+ }
+
+ fujitsu->data[fujitsu->idx++] = data;
+ if (fujitsu->idx == FUJITSU_LENGTH) {
+ input_report_abs(dev, ABS_X,
+ (fujitsu->data[2] << 7) | fujitsu->data[1]);
+ input_report_abs(dev, ABS_Y,
+ (fujitsu->data[4] << 7) | fujitsu->data[3]);
+ input_report_key(dev, BTN_TOUCH,
+ (fujitsu->data[0] & 0x03) != 2);
+ input_sync(dev);
+ fujitsu->idx = 0;
+ }
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * fujitsu_disconnect() is the opposite of fujitsu_connect()
+ */
+static void fujitsu_disconnect(struct serio *serio)
+{
+ struct fujitsu *fujitsu = serio_get_drvdata(serio);
+
+ input_get_device(fujitsu->dev);
+ input_unregister_device(fujitsu->dev);
+ serio_close(serio);
+ serio_set_drvdata(serio, NULL);
+ input_put_device(fujitsu->dev);
+ kfree(fujitsu);
+}
+
+/*
+ * fujitsu_connect() is the routine that is called when someone adds a
+ * new serio device that supports the Fujitsu protocol and registers it
+ * as input device.
+ */
+static int fujitsu_connect(struct serio *serio, struct serio_driver *drv)
+{
+ struct fujitsu *fujitsu;
+ struct input_dev *input_dev;
+ int err;
+
+ fujitsu = kzalloc(sizeof(struct fujitsu), GFP_KERNEL);
+ input_dev = input_allocate_device();
+ if (!fujitsu || !input_dev) {
+ err = -ENOMEM;
+ goto fail1;
+ }
+
+ fujitsu->serio = serio;
+ fujitsu->dev = input_dev;
+ snprintf(fujitsu->phys, sizeof(fujitsu->phys),
+ "%s/input0", serio->phys);
+
+ input_dev->name = "Fujitsu Serial Touchscreen";
+ input_dev->phys = fujitsu->phys;
+ input_dev->id.bustype = BUS_RS232;
+ input_dev->id.vendor = SERIO_FUJITSU;
+ input_dev->id.product = 0;
+ input_dev->id.version = 0x0100;
+ 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(input_dev, ABS_X, 0, 4096, 0, 0);
+ input_set_abs_params(input_dev, ABS_Y, 0, 4096, 0, 0);
+ serio_set_drvdata(serio, fujitsu);
+
+ err = serio_open(serio, drv);
+ if (err)
+ goto fail2;
+
+ err = input_register_device(fujitsu->dev);
+ if (err)
+ goto fail3;
+
+ return 0;
+
+ fail3:
+ serio_close(serio);
+ fail2:
+ serio_set_drvdata(serio, NULL);
+ fail1:
+ input_free_device(input_dev);
+ kfree(fujitsu);
+ return err;
+}
+
+/*
+ * The serio driver structure.
+ */
+static const struct serio_device_id fujitsu_serio_ids[] = {
+ {
+ .type = SERIO_RS232,
+ .proto = SERIO_FUJITSU,
+ .id = SERIO_ANY,
+ .extra = SERIO_ANY,
+ },
+ { 0 }
+};
+
+MODULE_DEVICE_TABLE(serio, fujitsu_serio_ids);
+
+static struct serio_driver fujitsu_drv = {
+ .driver = {
+ .name = "fujitsu_ts",
+ },
+ .description = DRIVER_DESC,
+ .id_table = fujitsu_serio_ids,
+ .interrupt = fujitsu_interrupt,
+ .connect = fujitsu_connect,
+ .disconnect = fujitsu_disconnect,
+};
+
+module_serio_driver(fujitsu_drv);