1 files changed, 406 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/elo.c b/drivers/input/touchscreen/elo.c
new file mode 100644
index 000000000..96173232e
--- /dev/null
+++ b/drivers/input/touchscreen/elo.c
@@ -0,0 +1,406 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Elo serial touchscreen driver
+ *
+ * Copyright (c) 2004 Vojtech Pavlik
+ */
+
+
+/*
+ * This driver can handle serial Elo touchscreens using either the Elo standard
+ * 'E271-2210' 10-byte protocol, Elo legacy 'E281A-4002' 6-byte protocol, Elo
+ * legacy 'E271-140' 4-byte protocol and Elo legacy 'E261-280' 3-byte protocol.
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/serio.h>
+#include <linux/ctype.h>
+
+#define DRIVER_DESC	"Elo serial touchscreen driver"
+
+MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+
+/*
+ * Definitions & global arrays.
+ */
+
+#define ELO_MAX_LENGTH		10
+
+#define ELO10_PACKET_LEN	8
+#define ELO10_TOUCH		0x03
+#define ELO10_PRESSURE		0x80
+
+#define ELO10_LEAD_BYTE		'U'
+
+#define ELO10_ID_CMD		'i'
+
+#define ELO10_TOUCH_PACKET	'T'
+#define ELO10_ACK_PACKET	'A'
+#define ELI10_ID_PACKET		'I'
+
+/*
+ * Per-touchscreen data.
+ */
+
+struct elo {
+	struct input_dev *dev;
+	struct serio *serio;
+	struct mutex cmd_mutex;
+	struct completion cmd_done;
+	int id;
+	int idx;
+	unsigned char expected_packet;
+	unsigned char csum;
+	unsigned char data[ELO_MAX_LENGTH];
+	unsigned char response[ELO10_PACKET_LEN];
+	char phys[32];
+};
+
+static void elo_process_data_10(struct elo *elo, unsigned char data)
+{
+	struct input_dev *dev = elo->dev;
+
+	elo->data[elo->idx] = data;
+
+	switch (elo->idx++) {
+	case 0:
+		elo->csum = 0xaa;
+		if (data != ELO10_LEAD_BYTE) {
+			dev_dbg(&elo->serio->dev,
+				"unsynchronized data: 0x%02x\n", data);
+			elo->idx = 0;
+		}
+		break;
+
+	case 9:
+		elo->idx = 0;
+		if (data != elo->csum) {
+			dev_dbg(&elo->serio->dev,
+				"bad checksum: 0x%02x, expected 0x%02x\n",
+				 data, elo->csum);
+			break;
+		}
+		if (elo->data[1] != elo->expected_packet) {
+			if (elo->data[1] != ELO10_TOUCH_PACKET)
+				dev_dbg(&elo->serio->dev,
+					"unexpected packet: 0x%02x\n",
+					 elo->data[1]);
+			break;
+		}
+		if (likely(elo->data[1] == ELO10_TOUCH_PACKET)) {
+			input_report_abs(dev, ABS_X, (elo->data[4] << 8) | elo->data[3]);
+			input_report_abs(dev, ABS_Y, (elo->data[6] << 8) | elo->data[5]);
+			if (elo->data[2] & ELO10_PRESSURE)
+				input_report_abs(dev, ABS_PRESSURE,
+						(elo->data[8] << 8) | elo->data[7]);
+			input_report_key(dev, BTN_TOUCH, elo->data[2] & ELO10_TOUCH);
+			input_sync(dev);
+		} else if (elo->data[1] == ELO10_ACK_PACKET) {
+			if (elo->data[2] == '0')
+				elo->expected_packet = ELO10_TOUCH_PACKET;
+			complete(&elo->cmd_done);
+		} else {
+			memcpy(elo->response, &elo->data[1], ELO10_PACKET_LEN);
+			elo->expected_packet = ELO10_ACK_PACKET;
+		}
+		break;
+	}
+	elo->csum += data;
+}
+
+static void elo_process_data_6(struct elo *elo, unsigned char data)
+{
+	struct input_dev *dev = elo->dev;
+
+	elo->data[elo->idx] = data;
+
+	switch (elo->idx++) {
+
+	case 0:
+		if ((data & 0xc0) != 0xc0)
+			elo->idx = 0;
+		break;
+
+	case 1:
+		if ((data & 0xc0) != 0x80)
+			elo->idx = 0;
+		break;
+
+	case 2:
+		if ((data & 0xc0) != 0x40)
+			elo->idx = 0;
+		break;
+
+	case 3:
+		if (data & 0xc0) {
+			elo->idx = 0;
+			break;
+		}
+
+		input_report_abs(dev, ABS_X, ((elo->data[0] & 0x3f) << 6) | (elo->data[1] & 0x3f));
+		input_report_abs(dev, ABS_Y, ((elo->data[2] & 0x3f) << 6) | (elo->data[3] & 0x3f));
+
+		if (elo->id == 2) {
+			input_report_key(dev, BTN_TOUCH, 1);
+			input_sync(dev);
+			elo->idx = 0;
+		}
+
+		break;
+
+	case 4:
+		if (data) {
+			input_sync(dev);
+			elo->idx = 0;
+		}
+		break;
+
+	case 5:
+		if ((data & 0xf0) == 0) {
+			input_report_abs(dev, ABS_PRESSURE, elo->data[5]);
+			input_report_key(dev, BTN_TOUCH, !!elo->data[5]);
+		}
+		input_sync(dev);
+		elo->idx = 0;
+		break;
+	}
+}
+
+static void elo_process_data_3(struct elo *elo, unsigned char data)
+{
+	struct input_dev *dev = elo->dev;
+
+	elo->data[elo->idx] = data;
+
+	switch (elo->idx++) {
+
+	case 0:
+		if ((data & 0x7f) != 0x01)
+			elo->idx = 0;
+		break;
+	case 2:
+		input_report_key(dev, BTN_TOUCH, !(elo->data[1] & 0x80));
+		input_report_abs(dev, ABS_X, elo->data[1]);
+		input_report_abs(dev, ABS_Y, elo->data[2]);
+		input_sync(dev);
+		elo->idx = 0;
+		break;
+	}
+}
+
+static irqreturn_t elo_interrupt(struct serio *serio,
+		unsigned char data, unsigned int flags)
+{
+	struct elo *elo = serio_get_drvdata(serio);
+
+	switch (elo->id) {
+	case 0:
+		elo_process_data_10(elo, data);
+		break;
+
+	case 1:
+	case 2:
+		elo_process_data_6(elo, data);
+		break;
+
+	case 3:
+		elo_process_data_3(elo, data);
+		break;
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int elo_command_10(struct elo *elo, unsigned char *packet)
+{
+	int rc = -1;
+	int i;
+	unsigned char csum = 0xaa + ELO10_LEAD_BYTE;
+
+	mutex_lock(&elo->cmd_mutex);
+
+	serio_pause_rx(elo->serio);
+	elo->expected_packet = toupper(packet[0]);
+	init_completion(&elo->cmd_done);
+	serio_continue_rx(elo->serio);
+
+	if (serio_write(elo->serio, ELO10_LEAD_BYTE))
+		goto out;
+
+	for (i = 0; i < ELO10_PACKET_LEN; i++) {
+		csum += packet[i];
+		if (serio_write(elo->serio, packet[i]))
+			goto out;
+	}
+
+	if (serio_write(elo->serio, csum))
+		goto out;
+
+	wait_for_completion_timeout(&elo->cmd_done, HZ);
+
+	if (elo->expected_packet == ELO10_TOUCH_PACKET) {
+		/* We are back in reporting mode, the command was ACKed */
+		memcpy(packet, elo->response, ELO10_PACKET_LEN);
+		rc = 0;
+	}
+
+ out:
+	mutex_unlock(&elo->cmd_mutex);
+	return rc;
+}
+
+static int elo_setup_10(struct elo *elo)
+{
+	static const char *elo_types[] = { "Accu", "Dura", "Intelli", "Carroll" };
+	struct input_dev *dev = elo->dev;
+	unsigned char packet[ELO10_PACKET_LEN] = { ELO10_ID_CMD };
+
+	if (elo_command_10(elo, packet))
+		return -1;
+
+	dev->id.version = (packet[5] << 8) | packet[4];
+
+	input_set_abs_params(dev, ABS_X, 96, 4000, 0, 0);
+	input_set_abs_params(dev, ABS_Y, 96, 4000, 0, 0);
+	if (packet[3] & ELO10_PRESSURE)
+		input_set_abs_params(dev, ABS_PRESSURE, 0, 255, 0, 0);
+
+	dev_info(&elo->serio->dev,
+		 "%sTouch touchscreen, fw: %02x.%02x, features: 0x%02x, controller: 0x%02x\n",
+		 elo_types[(packet[1] -'0') & 0x03],
+		 packet[5], packet[4], packet[3], packet[7]);
+
+	return 0;
+}
+
+/*
+ * elo_disconnect() is the opposite of elo_connect()
+ */
+
+static void elo_disconnect(struct serio *serio)
+{
+	struct elo *elo = serio_get_drvdata(serio);
+
+	input_get_device(elo->dev);
+	input_unregister_device(elo->dev);
+	serio_close(serio);
+	serio_set_drvdata(serio, NULL);
+	input_put_device(elo->dev);
+	kfree(elo);
+}
+
+/*
+ * elo_connect() is the routine that is called when someone adds a
+ * new serio device that supports Gunze protocol and registers it as
+ * an input device.
+ */
+
+static int elo_connect(struct serio *serio, struct serio_driver *drv)
+{
+	struct elo *elo;
+	struct input_dev *input_dev;
+	int err;
+
+	elo = kzalloc(sizeof(struct elo), GFP_KERNEL);
+	input_dev = input_allocate_device();
+	if (!elo || !input_dev) {
+		err = -ENOMEM;
+		goto fail1;
+	}
+
+	elo->serio = serio;
+	elo->id = serio->id.id;
+	elo->dev = input_dev;
+	elo->expected_packet = ELO10_TOUCH_PACKET;
+	mutex_init(&elo->cmd_mutex);
+	init_completion(&elo->cmd_done);
+	snprintf(elo->phys, sizeof(elo->phys), "%s/input0", serio->phys);
+
+	input_dev->name = "Elo Serial TouchScreen";
+	input_dev->phys = elo->phys;
+	input_dev->id.bustype = BUS_RS232;
+	input_dev->id.vendor = SERIO_ELO;
+	input_dev->id.product = elo->id;
+	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);
+
+	serio_set_drvdata(serio, elo);
+	err = serio_open(serio, drv);
+	if (err)
+		goto fail2;
+
+	switch (elo->id) {
+
+	case 0: /* 10-byte protocol */
+		if (elo_setup_10(elo)) {
+			err = -EIO;
+			goto fail3;
+		}
+
+		break;
+
+	case 1: /* 6-byte protocol */
+		input_set_abs_params(input_dev, ABS_PRESSURE, 0, 15, 0, 0);
+		fallthrough;
+
+	case 2: /* 4-byte protocol */
+		input_set_abs_params(input_dev, ABS_X, 96, 4000, 0, 0);
+		input_set_abs_params(input_dev, ABS_Y, 96, 4000, 0, 0);
+		break;
+
+	case 3: /* 3-byte protocol */
+		input_set_abs_params(input_dev, ABS_X, 0, 255, 0, 0);
+		input_set_abs_params(input_dev, ABS_Y, 0, 255, 0, 0);
+		break;
+	}
+
+	err = input_register_device(elo->dev);
+	if (err)
+		goto fail3;
+
+	return 0;
+
+ fail3: serio_close(serio);
+ fail2:	serio_set_drvdata(serio, NULL);
+ fail1:	input_free_device(input_dev);
+	kfree(elo);
+	return err;
+}
+
+/*
+ * The serio driver structure.
+ */
+
+static const struct serio_device_id elo_serio_ids[] = {
+	{
+		.type	= SERIO_RS232,
+		.proto	= SERIO_ELO,
+		.id	= SERIO_ANY,
+		.extra	= SERIO_ANY,
+	},
+	{ 0 }
+};
+
+MODULE_DEVICE_TABLE(serio, elo_serio_ids);
+
+static struct serio_driver elo_drv = {
+	.driver		= {
+		.name	= "elo",
+	},
+	.description	= DRIVER_DESC,
+	.id_table	= elo_serio_ids,
+	.interrupt	= elo_interrupt,
+	.connect	= elo_connect,
+	.disconnect	= elo_disconnect,
+};
+
+module_serio_driver(elo_drv);