From 83e53a8f120f2f273cf0ad717f5372ab79ac24fe Mon Sep 17 00:00:00 2001 From: Andrew Lunn Date: Sat, 11 Jan 2014 00:23:59 +0100 Subject: [PATCH] i2c: Add bus driver for for OSIF USB i2c device. OSIF, Open Source InterFace, is a USB based i2c bus master. The origional design was based on i2c-tiny-usb, but more modern versions of the firmware running on the MegaAVR microcontroller use a different protocol over the USB. This code is based on Barry Carter driver. Signed-off-by: Andrew Lunn Signed-off-by: Wolfram Sang --- drivers/i2c/busses/Kconfig | 10 ++ drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-robotfuzz-osif.c | 202 ++++++++++++++++++++++++ 3 files changed, 213 insertions(+) create mode 100644 drivers/i2c/busses/i2c-robotfuzz-osif.c diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 98a3f1ffc3b7..6bcdea5856af 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -874,6 +874,16 @@ config I2C_PARPORT_LIGHT This support is also available as a module. If so, the module will be called i2c-parport-light. +config I2C_ROBOTFUZZ_OSIF + tristate "RobotFuzz Open Source InterFace USB adapter" + depends on USB + help + If you say yes to this option, support will be included for the + RobotFuzz Open Source InterFace USB to I2C interface. + + This driver can also be built as a module. If so, the module + will be called i2c-osif. + config I2C_TAOS_EVM tristate "TAOS evaluation module" depends on TTY diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index dca041b1b99d..a08931fe73e1 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -84,6 +84,7 @@ obj-$(CONFIG_I2C_RCAR) += i2c-rcar.o obj-$(CONFIG_I2C_DIOLAN_U2C) += i2c-diolan-u2c.o obj-$(CONFIG_I2C_PARPORT) += i2c-parport.o obj-$(CONFIG_I2C_PARPORT_LIGHT) += i2c-parport-light.o +obj-$(CONFIG_I2C_ROBOTFUZZ_OSIF) += i2c-robotfuzz-osif.o obj-$(CONFIG_I2C_TAOS_EVM) += i2c-taos-evm.o obj-$(CONFIG_I2C_TINY_USB) += i2c-tiny-usb.o obj-$(CONFIG_I2C_VIPERBOARD) += i2c-viperboard.o diff --git a/drivers/i2c/busses/i2c-robotfuzz-osif.c b/drivers/i2c/busses/i2c-robotfuzz-osif.c new file mode 100644 index 000000000000..ced9c6a308d1 --- /dev/null +++ b/drivers/i2c/busses/i2c-robotfuzz-osif.c @@ -0,0 +1,202 @@ +/* + * Driver for RobotFuzz OSIF + * + * Copyright (c) 2013 Andrew Lunn + * Copyright (c) 2007 Barry Carter + * + * 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 +#include +#include +#include +#include +#include + +#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 = 0; + int i, cmd; + + for (i = 0; ret >= 0 && i < num; i++) { + pmsg = &msgs[i]; + + if (pmsg->flags & I2C_M_RD) { + cmd = OSIFI2C_READ; + + ret = osif_usb_read(adapter, cmd, pmsg->flags, + pmsg->addr, pmsg->buf, + pmsg->len); + if (ret != pmsg->len) { + dev_err(&adapter->dev, "failure reading data\n"); + return -EREMOTEIO; + } + } else { + cmd = OSIFI2C_WRITE; + + ret = osif_usb_write(adapter, cmd, 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 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 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 "); +MODULE_AUTHOR("Barry Carter "); +MODULE_DESCRIPTION("RobotFuzz OSIF driver"); +MODULE_LICENSE("GPL v2"); -- 2.34.1