v4.19.13 snapshot.
diff --git a/drivers/i2c/busses/i2c-robotfuzz-osif.c b/drivers/i2c/busses/i2c-robotfuzz-osif.c
new file mode 100644
index 0000000..d848cf5
--- /dev/null
+++ b/drivers/i2c/busses/i2c-robotfuzz-osif.c
@@ -0,0 +1,199 @@
+/*
+ * Driver for RobotFuzz OSIF
+ *
+ * Copyright (c) 2013 Andrew Lunn <andrew@lunn.ch>
+ * Copyright (c) 2007 Barry Carter <Barry.Carter@robotfuzz.com>
+ *
+ * Based on the i2c-tiny-usb by
+ *
+ * Copyright (C) 2006 Til Harbaum (Till@Harbaum.org)
+ *
+ * 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, version 2.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+
+#define OSIFI2C_READ 20
+#define OSIFI2C_WRITE 21
+#define OSIFI2C_STOP 22
+#define OSIFI2C_STATUS 23
+#define OSIFI2C_SET_BIT_RATE 24
+
+#define STATUS_ADDRESS_ACK 0
+#define STATUS_ADDRESS_NAK 2
+
+struct osif_priv {
+ struct usb_device *usb_dev;
+ struct usb_interface *interface;
+ struct i2c_adapter adapter;
+ unsigned char status;
+};
+
+static int osif_usb_read(struct i2c_adapter *adapter, int cmd,
+ int value, int index, void *data, int len)
+{
+ struct osif_priv *priv = adapter->algo_data;
+
+ return usb_control_msg(priv->usb_dev, usb_rcvctrlpipe(priv->usb_dev, 0),
+ cmd, USB_TYPE_VENDOR | USB_RECIP_INTERFACE |
+ USB_DIR_IN, value, index, data, len, 2000);
+}
+
+static int osif_usb_write(struct i2c_adapter *adapter, int cmd,
+ int value, int index, void *data, int len)
+{
+
+ struct osif_priv *priv = adapter->algo_data;
+
+ return usb_control_msg(priv->usb_dev, usb_sndctrlpipe(priv->usb_dev, 0),
+ cmd, USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
+ value, index, data, len, 2000);
+}
+
+static int osif_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
+ int num)
+{
+ struct osif_priv *priv = adapter->algo_data;
+ struct i2c_msg *pmsg;
+ int ret;
+ int i;
+
+ for (i = 0; i < num; i++) {
+ pmsg = &msgs[i];
+
+ if (pmsg->flags & I2C_M_RD) {
+ ret = osif_usb_read(adapter, OSIFI2C_READ,
+ pmsg->flags, pmsg->addr,
+ pmsg->buf, pmsg->len);
+ if (ret != pmsg->len) {
+ dev_err(&adapter->dev, "failure reading data\n");
+ return -EREMOTEIO;
+ }
+ } else {
+ ret = osif_usb_write(adapter, OSIFI2C_WRITE,
+ pmsg->flags, pmsg->addr,
+ pmsg->buf, pmsg->len);
+ if (ret != pmsg->len) {
+ dev_err(&adapter->dev, "failure writing data\n");
+ return -EREMOTEIO;
+ }
+ }
+
+ ret = osif_usb_read(adapter, OSIFI2C_STOP, 0, 0, NULL, 0);
+ if (ret) {
+ dev_err(&adapter->dev, "failure sending STOP\n");
+ return -EREMOTEIO;
+ }
+
+ /* read status */
+ ret = osif_usb_read(adapter, OSIFI2C_STATUS, 0, 0,
+ &priv->status, 1);
+ if (ret != 1) {
+ dev_err(&adapter->dev, "failure reading status\n");
+ return -EREMOTEIO;
+ }
+
+ if (priv->status != STATUS_ADDRESS_ACK) {
+ dev_dbg(&adapter->dev, "status = %d\n", priv->status);
+ return -EREMOTEIO;
+ }
+ }
+
+ return i;
+}
+
+static u32 osif_func(struct i2c_adapter *adapter)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm osif_algorithm = {
+ .master_xfer = osif_xfer,
+ .functionality = osif_func,
+};
+
+#define USB_OSIF_VENDOR_ID 0x1964
+#define USB_OSIF_PRODUCT_ID 0x0001
+
+static const struct usb_device_id osif_table[] = {
+ { USB_DEVICE(USB_OSIF_VENDOR_ID, USB_OSIF_PRODUCT_ID) },
+ { }
+};
+MODULE_DEVICE_TABLE(usb, osif_table);
+
+static int osif_probe(struct usb_interface *interface,
+ const struct usb_device_id *id)
+{
+ int ret;
+ struct osif_priv *priv;
+ u16 version;
+
+ priv = devm_kzalloc(&interface->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->usb_dev = usb_get_dev(interface_to_usbdev(interface));
+ priv->interface = interface;
+
+ usb_set_intfdata(interface, priv);
+
+ priv->adapter.owner = THIS_MODULE;
+ priv->adapter.class = I2C_CLASS_HWMON;
+ priv->adapter.algo = &osif_algorithm;
+ priv->adapter.algo_data = priv;
+ snprintf(priv->adapter.name, sizeof(priv->adapter.name),
+ "OSIF at bus %03d device %03d",
+ priv->usb_dev->bus->busnum, priv->usb_dev->devnum);
+
+ /*
+ * Set bus frequency. The frequency is:
+ * 120,000,000 / ( 16 + 2 * div * 4^prescale).
+ * Using dev = 52, prescale = 0 give 100KHz */
+ ret = osif_usb_read(&priv->adapter, OSIFI2C_SET_BIT_RATE, 52, 0,
+ NULL, 0);
+ if (ret) {
+ dev_err(&interface->dev, "failure sending bit rate");
+ usb_put_dev(priv->usb_dev);
+ return ret;
+ }
+
+ i2c_add_adapter(&(priv->adapter));
+
+ version = le16_to_cpu(priv->usb_dev->descriptor.bcdDevice);
+ dev_info(&interface->dev,
+ "version %x.%02x found at bus %03d address %03d",
+ version >> 8, version & 0xff,
+ priv->usb_dev->bus->busnum, priv->usb_dev->devnum);
+
+ return 0;
+}
+
+static void osif_disconnect(struct usb_interface *interface)
+{
+ struct osif_priv *priv = usb_get_intfdata(interface);
+
+ i2c_del_adapter(&(priv->adapter));
+ usb_set_intfdata(interface, NULL);
+ usb_put_dev(priv->usb_dev);
+}
+
+static struct usb_driver osif_driver = {
+ .name = "RobotFuzz Open Source InterFace, OSIF",
+ .probe = osif_probe,
+ .disconnect = osif_disconnect,
+ .id_table = osif_table,
+};
+
+module_usb_driver(osif_driver);
+
+MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
+MODULE_AUTHOR("Barry Carter <barry.carter@robotfuzz.com>");
+MODULE_DESCRIPTION("RobotFuzz OSIF driver");
+MODULE_LICENSE("GPL v2");