// SPDX-License-Identifier: GPL-2.0-only/* * Touchright serial touchscreen driver * * Copyright (c) 2006 Rick Koch <n1gp@hotmail.com> * * Based on MicroTouch driver (drivers/input/touchscreen/mtouch.c) * 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	"Touchright serial touchscreen driver" MODULE_AUTHOR("Rick Koch <n1gp@hotmail.com>");MODULE_DESCRIPTION(DRIVER_DESC);MODULE_LICENSE("GPL"); /* * Definitions & global arrays. */ #define TR_FORMAT_TOUCH_BIT	0x01#define TR_FORMAT_STATUS_BYTE	0x40#define TR_FORMAT_STATUS_MASK	~TR_FORMAT_TOUCH_BIT #define TR_LENGTH 5 #define TR_MIN_XC 0#define TR_MAX_XC 0x1ff#define TR_MIN_YC 0#define TR_MAX_YC 0x1ff /* * Per-touchscreen data. */ struct tr {	struct input_dev *dev;	struct serio *serio;	int idx;	unsigned char data[TR_LENGTH];	char phys[32];}; static irqreturn_t tr_interrupt(struct serio *serio,		unsigned char data, unsigned int flags){	struct tr *tr = serio_get_drvdata(serio);	struct input_dev *dev = tr->dev; 	tr->data[tr->idx] = data; 	if ((tr->data[0] & TR_FORMAT_STATUS_MASK) == TR_FORMAT_STATUS_BYTE) {		if (++tr->idx == TR_LENGTH) {			input_report_abs(dev, ABS_X,				(tr->data[1] << 5) | (tr->data[2] >> 1));			input_report_abs(dev, ABS_Y,				(tr->data[3] << 5) | (tr->data[4] >> 1));			input_report_key(dev, BTN_TOUCH,				tr->data[0] & TR_FORMAT_TOUCH_BIT);			input_sync(dev);			tr->idx = 0;		}	} 	return IRQ_HANDLED;} /* * tr_disconnect() is the opposite of tr_connect() */ static void tr_disconnect(struct serio *serio){	struct tr *tr = serio_get_drvdata(serio); 	input_get_device(tr->dev);	input_unregister_device(tr->dev);	serio_close(serio);	serio_set_drvdata(serio, NULL);	input_put_device(tr->dev);	kfree(tr);} /* * tr_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 tr_connect(struct serio *serio, struct serio_driver *drv){	struct tr *tr;	struct input_dev *input_dev;	int err; 	tr = kzalloc(sizeof(*tr), GFP_KERNEL);	input_dev = input_allocate_device();	if (!tr || !input_dev) {		err = -ENOMEM;		goto fail1;	} 	tr->serio = serio;	tr->dev = input_dev;	snprintf(tr->phys, sizeof(tr->phys), "%s/input0", serio->phys); 	input_dev->name = "Touchright Serial TouchScreen";	input_dev->phys = tr->phys;	input_dev->id.bustype = BUS_RS232;	input_dev->id.vendor = SERIO_TOUCHRIGHT;	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(tr->dev, ABS_X, TR_MIN_XC, TR_MAX_XC, 0, 0);	input_set_abs_params(tr->dev, ABS_Y, TR_MIN_YC, TR_MAX_YC, 0, 0); 	serio_set_drvdata(serio, tr); 	err = serio_open(serio, drv);	if (err)		goto fail2; 	err = input_register_device(tr->dev);	if (err)		goto fail3; 	return 0;  fail3:	serio_close(serio); fail2:	serio_set_drvdata(serio, NULL); fail1:	input_free_device(input_dev);	kfree(tr);	return err;} /* * The serio driver structure. */ static const struct serio_device_id tr_serio_ids[] = {	{		.type	= SERIO_RS232,		.proto	= SERIO_TOUCHRIGHT,		.id	= SERIO_ANY,		.extra	= SERIO_ANY,	},	{ 0 }}; MODULE_DEVICE_TABLE(serio, tr_serio_ids); static struct serio_driver tr_drv = {	.driver		= {		.name	= "touchright",	},	.description	= DRIVER_DESC,	.id_table	= tr_serio_ids,	.interrupt	= tr_interrupt,	.connect	= tr_connect,	.disconnect	= tr_disconnect,}; module_serio_driver(tr_drv);