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/hid/hid-roccat-common.c b/drivers/hid/hid-roccat-common.c
new file mode 100644
index 0000000..02e28e9
--- /dev/null
+++ b/drivers/hid/hid-roccat-common.c
@@ -0,0 +1,180 @@
+/*
+ * Roccat common functions for device specific drivers
+ *
+ * Copyright (c) 2011 Stefan Achatz <erazor_de@users.sourceforge.net>
+ */
+
+/*
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ */
+
+#include <linux/hid.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include "hid-roccat-common.h"
+
+static inline uint16_t roccat_common2_feature_report(uint8_t report_id)
+{
+	return 0x300 | report_id;
+}
+
+int roccat_common2_receive(struct usb_device *usb_dev, uint report_id,
+		void *data, uint size)
+{
+	char *buf;
+	int len;
+
+	buf = kmalloc(size, GFP_KERNEL);
+	if (buf == NULL)
+		return -ENOMEM;
+
+	len = usb_control_msg(usb_dev, usb_rcvctrlpipe(usb_dev, 0),
+			HID_REQ_GET_REPORT,
+			USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
+			roccat_common2_feature_report(report_id),
+			0, buf, size, USB_CTRL_SET_TIMEOUT);
+
+	memcpy(data, buf, size);
+	kfree(buf);
+	return ((len < 0) ? len : ((len != size) ? -EIO : 0));
+}
+EXPORT_SYMBOL_GPL(roccat_common2_receive);
+
+int roccat_common2_send(struct usb_device *usb_dev, uint report_id,
+		void const *data, uint size)
+{
+	char *buf;
+	int len;
+
+	buf = kmemdup(data, size, GFP_KERNEL);
+	if (buf == NULL)
+		return -ENOMEM;
+
+	len = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
+			HID_REQ_SET_REPORT,
+			USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
+			roccat_common2_feature_report(report_id),
+			0, buf, size, USB_CTRL_SET_TIMEOUT);
+
+	kfree(buf);
+	return ((len < 0) ? len : ((len != size) ? -EIO : 0));
+}
+EXPORT_SYMBOL_GPL(roccat_common2_send);
+
+enum roccat_common2_control_states {
+	ROCCAT_COMMON_CONTROL_STATUS_CRITICAL = 0,
+	ROCCAT_COMMON_CONTROL_STATUS_OK = 1,
+	ROCCAT_COMMON_CONTROL_STATUS_INVALID = 2,
+	ROCCAT_COMMON_CONTROL_STATUS_BUSY = 3,
+	ROCCAT_COMMON_CONTROL_STATUS_CRITICAL_NEW = 4,
+};
+
+static int roccat_common2_receive_control_status(struct usb_device *usb_dev)
+{
+	int retval;
+	struct roccat_common2_control control;
+
+	do {
+		msleep(50);
+		retval = roccat_common2_receive(usb_dev,
+				ROCCAT_COMMON_COMMAND_CONTROL,
+				&control, sizeof(struct roccat_common2_control));
+
+		if (retval)
+			return retval;
+
+		switch (control.value) {
+		case ROCCAT_COMMON_CONTROL_STATUS_OK:
+			return 0;
+		case ROCCAT_COMMON_CONTROL_STATUS_BUSY:
+			msleep(500);
+			continue;
+		case ROCCAT_COMMON_CONTROL_STATUS_INVALID:
+		case ROCCAT_COMMON_CONTROL_STATUS_CRITICAL:
+		case ROCCAT_COMMON_CONTROL_STATUS_CRITICAL_NEW:
+			return -EINVAL;
+		default:
+			dev_err(&usb_dev->dev,
+					"roccat_common2_receive_control_status: "
+					"unknown response value 0x%x\n",
+					control.value);
+			return -EINVAL;
+		}
+
+	} while (1);
+}
+
+int roccat_common2_send_with_status(struct usb_device *usb_dev,
+		uint command, void const *buf, uint size)
+{
+	int retval;
+
+	retval = roccat_common2_send(usb_dev, command, buf, size);
+	if (retval)
+		return retval;
+
+	msleep(100);
+
+	return roccat_common2_receive_control_status(usb_dev);
+}
+EXPORT_SYMBOL_GPL(roccat_common2_send_with_status);
+
+int roccat_common2_device_init_struct(struct usb_device *usb_dev,
+		struct roccat_common2_device *dev)
+{
+	mutex_init(&dev->lock);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(roccat_common2_device_init_struct);
+
+ssize_t roccat_common2_sysfs_read(struct file *fp, struct kobject *kobj,
+		char *buf, loff_t off, size_t count,
+		size_t real_size, uint command)
+{
+	struct device *dev =
+			container_of(kobj, struct device, kobj)->parent->parent;
+	struct roccat_common2_device *roccat_dev = hid_get_drvdata(dev_get_drvdata(dev));
+	struct usb_device *usb_dev = interface_to_usbdev(to_usb_interface(dev));
+	int retval;
+
+	if (off >= real_size)
+		return 0;
+
+	if (off != 0 || count != real_size)
+		return -EINVAL;
+
+	mutex_lock(&roccat_dev->lock);
+	retval = roccat_common2_receive(usb_dev, command, buf, real_size);
+	mutex_unlock(&roccat_dev->lock);
+
+	return retval ? retval : real_size;
+}
+EXPORT_SYMBOL_GPL(roccat_common2_sysfs_read);
+
+ssize_t roccat_common2_sysfs_write(struct file *fp, struct kobject *kobj,
+		void const *buf, loff_t off, size_t count,
+		size_t real_size, uint command)
+{
+	struct device *dev =
+			container_of(kobj, struct device, kobj)->parent->parent;
+	struct roccat_common2_device *roccat_dev = hid_get_drvdata(dev_get_drvdata(dev));
+	struct usb_device *usb_dev = interface_to_usbdev(to_usb_interface(dev));
+	int retval;
+
+	if (off != 0 || count != real_size)
+		return -EINVAL;
+
+	mutex_lock(&roccat_dev->lock);
+	retval = roccat_common2_send_with_status(usb_dev, command, buf, real_size);
+	mutex_unlock(&roccat_dev->lock);
+
+	return retval ? retval : real_size;
+}
+EXPORT_SYMBOL_GPL(roccat_common2_sysfs_write);
+
+MODULE_AUTHOR("Stefan Achatz");
+MODULE_DESCRIPTION("USB Roccat common driver");
+MODULE_LICENSE("GPL v2");