diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-robotfuzz-osif.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-robotfuzz-osif.c | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-robotfuzz-osif.c b/drivers/i2c/busses/i2c-robotfuzz-osif.c new file mode 100644 index 0000000000..66dfa211e7 --- /dev/null +++ b/drivers/i2c/busses/i2c-robotfuzz-osif.c @@ -0,0 +1,196 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * 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) + */ + +#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_write(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_write(&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"); |