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 <[email protected]> driver.
Signed-off-by: Andrew Lunn <[email protected]> CC: Emmanuel Deloget <[email protected]> CC: Barry Carter <[email protected]> --- drivers/i2c/busses/Kconfig | 10 ++ drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-osif.c | 267 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 278 insertions(+) create mode 100644 drivers/i2c/busses/i2c-osif.c diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index cdcbd8368ed3..e7ed9edd79e2 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -788,6 +788,16 @@ config I2C_DIOLAN_U2C This driver can also be built as a module. If so, the module will be called i2c-diolan-u2c. +config I2C_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_PARPORT tristate "Parallel port adapter" depends on PARPORT diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index d00997f3eb3b..4c147862b2a7 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -79,6 +79,7 @@ obj-$(CONFIG_I2C_RCAR) += i2c-rcar.o # External I2C/SMBus adapter drivers obj-$(CONFIG_I2C_DIOLAN_U2C) += i2c-diolan-u2c.o +obj-$(CONFIG_I2C_OSIF) += i2c-osif.o obj-$(CONFIG_I2C_PARPORT) += i2c-parport.o obj-$(CONFIG_I2C_PARPORT_LIGHT) += i2c-parport-light.o obj-$(CONFIG_I2C_TAOS_EVM) += i2c-taos-evm.o diff --git a/drivers/i2c/busses/i2c-osif.c b/drivers/i2c/busses/i2c-osif.c new file mode 100644 index 000000000000..8c12407d88c2 --- /dev/null +++ b/drivers/i2c/busses/i2c-osif.c @@ -0,0 +1,267 @@ +/* + * Driver for RobotFuzz OSIF + * + * Copyright (c) 2007 Barry Carter <[email protected]> + * Copyright (c) 2013 Andrew Lunn <[email protected]> + * + * Based on the i2c-tiny-usb by + * + * Copyright (C) 2006 Til Harbaum ([email protected]) + * + * 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 DRIVER_AUTHOR "Barry Carter <[email protected]>," \ + "Andrew Lunn <[email protected]>" +#define DRIVER_DESC "OSIF driver" + +#define OSIFI2C_READ 20 /* Read from i2c bus */ +#define OSIFI2C_WRITE 21 /* Write to i2c bus */ +#define OSIFI2C_STOP 22 /* Send stop condition */ +#define OSIFI2C_STATUS 23 /* Get status from i2c action */ +#define OSIFI2C_SET_BIT_RATE 24 /* Set the bit rate & prescaler */ + +#define STATUS_ADDRESS_ACK 0 +#define STATUS_ADDRESS_NAK 2 + +static int usb_read(struct i2c_adapter *adapter, int cmd, + int value, int index, void *data, int len); + +static int usb_write(struct i2c_adapter *adapter, int cmd, + int value, int index, void *data, int len); + +/* ----- begin of i2c layer ---------------------------------------------- */ + +static int usb_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num) +{ + unsigned char *pstatus; + struct i2c_msg *pmsg; + int ret = 0; + int i, cmd; + + dev_dbg(&adapter->dev, "master xfer %d messages:\n", num); + + pstatus = kmalloc(sizeof(*pstatus), GFP_KERNEL); + if (!pstatus) + return -ENOMEM; + + for (i = 0; ret >= 0 && i < num; i++) { + + pmsg = &msgs[i]; + + dev_dbg(&adapter->dev, + " %d: %s (flags %d) %d bytes to 0x%02x\n", + i, pmsg->flags & I2C_M_RD ? "read" : "write", + pmsg->flags, pmsg->len, pmsg->addr); + + if (pmsg->flags & I2C_M_RD) { + cmd = OSIFI2C_READ; + + ret = usb_read(adapter, cmd, pmsg->flags, pmsg->addr, + pmsg->buf, pmsg->len); + if (ret != pmsg->len) { + dev_err(&adapter->dev, + "failure reading data\n"); + ret = -EREMOTEIO; + goto out; + } + } else { + cmd = OSIFI2C_WRITE; + + ret = usb_write(adapter, cmd, pmsg->flags, pmsg->addr, + pmsg->buf, pmsg->len); + if (ret != pmsg->len) { + dev_err(&adapter->dev, + "failure writing data\n"); + ret = -EREMOTEIO; + goto out; + } + } + + ret = usb_read(adapter, OSIFI2C_STOP, 0, 0, NULL, 0); + if (ret != 0) { + dev_err(&adapter->dev, "failure sending STOP\n"); + ret = -EREMOTEIO; + goto out; + } + + /* read status */ + ret = usb_read(adapter, OSIFI2C_STATUS, 0, 0, pstatus, 1); + if (ret != 1) { + dev_err(&adapter->dev, "failure reading status\n"); + ret = -EREMOTEIO; + goto out; + } + + dev_dbg(&adapter->dev, "status = %d\n", *pstatus); + if (*pstatus != STATUS_ADDRESS_ACK) { + ret = -EREMOTEIO; + goto out; + } + } + + ret = i; +out: + kfree(pstatus); + return ret; +} + +static u32 usb_func(struct i2c_adapter *adapter) +{ + /* configure for I2c mode and SMBUS emulation */ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +/* This is the actual algorithm we define */ +static struct i2c_algorithm usb_algorithm = { + .master_xfer = usb_xfer, + .functionality = usb_func, +}; + +/* ----- end of i2c layer ---------------------------------------------- */ + +/* ----- begin of usb layer ---------------------------------------------- */ + +/* the usb i2c interface uses a vid/pid pair donated by ftdi */ +#define USB_OSIF_VENDOR_ID 0x1964 +#define USB_OSIF_PRODUCT_ID 0x0001 + +/* table of devices that work with this driver */ +static struct usb_device_id osif_table[] = { + { USB_DEVICE(USB_OSIF_VENDOR_ID, USB_OSIF_PRODUCT_ID) }, + { } /* Terminating entry */ +}; + +MODULE_DEVICE_TABLE(usb, osif_table); + +/* Structure to hold all of our device specific stuff */ +struct priv { + struct usb_device *usb_dev; /* the usb device for this device */ + struct usb_interface *interface; /* the interface for this device */ + struct i2c_adapter adapter; /* i2c related things */ +}; + +static int usb_read(struct i2c_adapter *adapter, int cmd, + int value, int index, void *data, int len) +{ + struct priv *priv = (struct priv *)adapter->algo_data; + + /* do control transfer */ + 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 usb_write(struct i2c_adapter *adapter, int cmd, + int value, int index, void *data, int len) +{ + + struct priv *priv = (struct priv *)adapter->algo_data; + + /* do control transfer */ + 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 void osif_free(struct priv *priv) +{ + usb_put_dev(priv->usb_dev); +} + +static int osif_probe(struct usb_interface *interface, + const struct usb_device_id *id) +{ + struct priv *priv = NULL; + int retval = -ENOMEM; + u16 version; + + dev_dbg(&interface->dev, "probing usb device"); + + /* allocate memory for our device state and initialize it */ + priv = devm_kzalloc(&interface->dev, sizeof(*priv), GFP_KERNEL); + if (priv == NULL) { + dev_err(&interface->dev, "Out of memory\n"); + goto error; + } + + priv->usb_dev = usb_get_dev(interface_to_usbdev(interface)); + priv->interface = interface; + + /* save our data pointer in this interface device */ + usb_set_intfdata(interface, priv); + + 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); + + /* setup i2c adapter description */ + priv->adapter.owner = THIS_MODULE; + priv->adapter.class = I2C_CLASS_HWMON; + priv->adapter.algo = &usb_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 */ + retval = usb_read(&priv->adapter, OSIFI2C_SET_BIT_RATE, 52, 0, NULL, 0); + if (retval != 0) { + dev_err(&interface->dev, "failure sending bit rate"); + retval = -EREMOTEIO; + goto error; + } + + /* and finally attach to i2c layer */ + i2c_add_adapter(&(priv->adapter)); + + /* inform user about successful attachment to i2c layer */ + dev_info(&priv->adapter.dev, "connected OSIF device\n"); + + return 0; + +error: + + if (priv) + osif_free(priv); + + return retval; +} + +static void osif_disconnect(struct usb_interface *interface) +{ + struct priv *priv = usb_get_intfdata(interface); + + i2c_del_adapter(&(priv->adapter)); + usb_set_intfdata(interface, NULL); + osif_free(priv); +} + +static struct usb_driver osif_driver = { + .name = "Open Source InterFace OSIF", + .probe = osif_probe, + .disconnect = osif_disconnect, + .id_table = osif_table, +}; + +module_usb_driver(osif_driver); + +/* ----- end of usb layer ---------------------------------------------- */ + +MODULE_AUTHOR(DRIVER_AUTHOR); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL"); -- 1.8.4.rc3 -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
