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
<barry.carter@xxxxxxxxx> driver.
Signed-off-by: Andrew Lunn <andrew@xxxxxxx>
CC: Emmanuel Deloget <logout@xxxxxxx>
CC: Barry Carter <barry.carter@xxxxxxxxx>
---
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 <Barry.Carter@xxxxxxxxxxxxx>
+ * Copyright (c) 2013 Andrew Lunn <andrew@xxxxxxx>
+ *
+ * Based on the i2c-tiny-usb by
+ *
+ * Copyright (C) 2006 Til Harbaum (Till@xxxxxxxxxxx)
+ *
+ * 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 <barry.carter@xxxxxxxxxxxxx>," \
+ "Andrew Lunn <andrew@xxxxxxx>"
+#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");
--
1.8.5.1
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