File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/input/touchscreen/htcpen.c b/drivers/input/touchscreen/htcpen.c
new file mode 100644
index 0000000..92e2243
--- /dev/null
+++ b/drivers/input/touchscreen/htcpen.c
@@ -0,0 +1,248 @@
+/*
+ * HTC Shift touchscreen driver
+ *
+ * Copyright (C) 2008 Pau Oliva Fora <pof@eslack.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/isa.h>
+#include <linux/ioport.h>
+#include <linux/dmi.h>
+
+MODULE_AUTHOR("Pau Oliva Fora <pau@eslack.org>");
+MODULE_DESCRIPTION("HTC Shift touchscreen driver");
+MODULE_LICENSE("GPL");
+
+#define HTCPEN_PORT_IRQ_CLEAR	0x068
+#define HTCPEN_PORT_INIT	0x06c
+#define HTCPEN_PORT_INDEX	0x0250
+#define HTCPEN_PORT_DATA	0x0251
+#define HTCPEN_IRQ		3
+
+#define DEVICE_ENABLE		0xa2
+#define DEVICE_DISABLE		0xa3
+
+#define X_INDEX			3
+#define Y_INDEX			5
+#define TOUCH_INDEX		0xb
+#define LSB_XY_INDEX		0xc
+#define X_AXIS_MAX		2040
+#define Y_AXIS_MAX		2040
+
+static bool invert_x;
+module_param(invert_x, bool, 0644);
+MODULE_PARM_DESC(invert_x, "If set, X axis is inverted");
+static bool invert_y;
+module_param(invert_y, bool, 0644);
+MODULE_PARM_DESC(invert_y, "If set, Y axis is inverted");
+
+static irqreturn_t htcpen_interrupt(int irq, void *handle)
+{
+	struct input_dev *htcpen_dev = handle;
+	unsigned short x, y, xy;
+
+	/* 0 = press; 1 = release */
+	outb_p(TOUCH_INDEX, HTCPEN_PORT_INDEX);
+
+	if (inb_p(HTCPEN_PORT_DATA)) {
+		input_report_key(htcpen_dev, BTN_TOUCH, 0);
+	} else {
+		outb_p(X_INDEX, HTCPEN_PORT_INDEX);
+		x = inb_p(HTCPEN_PORT_DATA);
+
+		outb_p(Y_INDEX, HTCPEN_PORT_INDEX);
+		y = inb_p(HTCPEN_PORT_DATA);
+
+		outb_p(LSB_XY_INDEX, HTCPEN_PORT_INDEX);
+		xy = inb_p(HTCPEN_PORT_DATA);
+
+		/* get high resolution value of X and Y using LSB */
+		x = X_AXIS_MAX - ((x * 8) + ((xy >> 4) & 0xf));
+		y = (y * 8) + (xy & 0xf);
+		if (invert_x)
+			x = X_AXIS_MAX - x;
+		if (invert_y)
+			y = Y_AXIS_MAX - y;
+
+		if (x != X_AXIS_MAX && x != 0) {
+			input_report_key(htcpen_dev, BTN_TOUCH, 1);
+			input_report_abs(htcpen_dev, ABS_X, x);
+			input_report_abs(htcpen_dev, ABS_Y, y);
+		}
+	}
+
+	input_sync(htcpen_dev);
+
+	inb_p(HTCPEN_PORT_IRQ_CLEAR);
+
+	return IRQ_HANDLED;
+}
+
+static int htcpen_open(struct input_dev *dev)
+{
+	outb_p(DEVICE_ENABLE, HTCPEN_PORT_INIT);
+
+	return 0;
+}
+
+static void htcpen_close(struct input_dev *dev)
+{
+	outb_p(DEVICE_DISABLE, HTCPEN_PORT_INIT);
+	synchronize_irq(HTCPEN_IRQ);
+}
+
+static int htcpen_isa_probe(struct device *dev, unsigned int id)
+{
+	struct input_dev *htcpen_dev;
+	int err = -EBUSY;
+
+	if (!request_region(HTCPEN_PORT_IRQ_CLEAR, 1, "htcpen")) {
+		printk(KERN_ERR "htcpen: unable to get IO region 0x%x\n",
+			HTCPEN_PORT_IRQ_CLEAR);
+		goto request_region1_failed;
+	}
+
+	if (!request_region(HTCPEN_PORT_INIT, 1, "htcpen")) {
+		printk(KERN_ERR "htcpen: unable to get IO region 0x%x\n",
+			HTCPEN_PORT_INIT);
+		goto request_region2_failed;
+	}
+
+	if (!request_region(HTCPEN_PORT_INDEX, 2, "htcpen")) {
+		printk(KERN_ERR "htcpen: unable to get IO region 0x%x\n",
+			HTCPEN_PORT_INDEX);
+		goto request_region3_failed;
+	}
+
+	htcpen_dev = input_allocate_device();
+	if (!htcpen_dev) {
+		printk(KERN_ERR "htcpen: can't allocate device\n");
+		err = -ENOMEM;
+		goto input_alloc_failed;
+	}
+
+	htcpen_dev->name = "HTC Shift EC TouchScreen";
+	htcpen_dev->id.bustype = BUS_ISA;
+
+	htcpen_dev->evbit[0] = BIT_MASK(EV_ABS) | BIT_MASK(EV_KEY);
+	htcpen_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+	input_set_abs_params(htcpen_dev, ABS_X, 0, X_AXIS_MAX, 0, 0);
+	input_set_abs_params(htcpen_dev, ABS_Y, 0, Y_AXIS_MAX, 0, 0);
+
+	htcpen_dev->open = htcpen_open;
+	htcpen_dev->close = htcpen_close;
+
+	err = request_irq(HTCPEN_IRQ, htcpen_interrupt, 0, "htcpen",
+			htcpen_dev);
+	if (err) {
+		printk(KERN_ERR "htcpen: irq busy\n");
+		goto request_irq_failed;
+	}
+
+	inb_p(HTCPEN_PORT_IRQ_CLEAR);
+
+	err = input_register_device(htcpen_dev);
+	if (err)
+		goto input_register_failed;
+
+	dev_set_drvdata(dev, htcpen_dev);
+
+	return 0;
+
+ input_register_failed:
+	free_irq(HTCPEN_IRQ, htcpen_dev);
+ request_irq_failed:
+	input_free_device(htcpen_dev);
+ input_alloc_failed:
+	release_region(HTCPEN_PORT_INDEX, 2);
+ request_region3_failed:
+	release_region(HTCPEN_PORT_INIT, 1);
+ request_region2_failed:
+	release_region(HTCPEN_PORT_IRQ_CLEAR, 1);
+ request_region1_failed:
+	return err;
+}
+
+static int htcpen_isa_remove(struct device *dev, unsigned int id)
+{
+	struct input_dev *htcpen_dev = dev_get_drvdata(dev);
+
+	input_unregister_device(htcpen_dev);
+
+	free_irq(HTCPEN_IRQ, htcpen_dev);
+
+	release_region(HTCPEN_PORT_INDEX, 2);
+	release_region(HTCPEN_PORT_INIT, 1);
+	release_region(HTCPEN_PORT_IRQ_CLEAR, 1);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int htcpen_isa_suspend(struct device *dev, unsigned int n,
+				pm_message_t state)
+{
+	outb_p(DEVICE_DISABLE, HTCPEN_PORT_INIT);
+
+	return 0;
+}
+
+static int htcpen_isa_resume(struct device *dev, unsigned int n)
+{
+	outb_p(DEVICE_ENABLE, HTCPEN_PORT_INIT);
+
+	return 0;
+}
+#endif
+
+static struct isa_driver htcpen_isa_driver = {
+	.probe		= htcpen_isa_probe,
+	.remove		= htcpen_isa_remove,
+#ifdef CONFIG_PM
+	.suspend	= htcpen_isa_suspend,
+	.resume		= htcpen_isa_resume,
+#endif
+	.driver = {
+		.owner	= THIS_MODULE,
+		.name	= "htcpen",
+	}
+};
+
+static struct dmi_system_id htcshift_dmi_table[] __initdata = {
+	{
+		.ident = "Shift",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "High Tech Computer Corp"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Shift"),
+		},
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(dmi, htcshift_dmi_table);
+
+static int __init htcpen_isa_init(void)
+{
+	if (!dmi_check_system(htcshift_dmi_table))
+		return -ENODEV;
+
+	return isa_register_driver(&htcpen_isa_driver, 1);
+}
+
+static void __exit htcpen_isa_exit(void)
+{
+	isa_unregister_driver(&htcpen_isa_driver);
+}
+
+module_init(htcpen_isa_init);
+module_exit(htcpen_isa_exit);