blob: ced9c6a308d1258a4bf664067670c9dfa650a424 [file] [log] [blame]
Andrew Lunn83e53a82014-01-11 00:23:59 +01001/*
2 * Driver for RobotFuzz OSIF
3 *
4 * Copyright (c) 2013 Andrew Lunn <andrew@lunn.ch>
5 * Copyright (c) 2007 Barry Carter <Barry.Carter@robotfuzz.com>
6 *
7 * Based on the i2c-tiny-usb by
8 *
9 * Copyright (C) 2006 Til Harbaum (Till@Harbaum.org)
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License as
13 * published by the Free Software Foundation, version 2.
14 */
15
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/errno.h>
19#include <linux/i2c.h>
20#include <linux/slab.h>
21#include <linux/usb.h>
22
23#define OSIFI2C_READ 20
24#define OSIFI2C_WRITE 21
25#define OSIFI2C_STOP 22
26#define OSIFI2C_STATUS 23
27#define OSIFI2C_SET_BIT_RATE 24
28
29#define STATUS_ADDRESS_ACK 0
30#define STATUS_ADDRESS_NAK 2
31
32struct osif_priv {
33 struct usb_device *usb_dev;
34 struct usb_interface *interface;
35 struct i2c_adapter adapter;
36 unsigned char status;
37};
38
39static int osif_usb_read(struct i2c_adapter *adapter, int cmd,
40 int value, int index, void *data, int len)
41{
42 struct osif_priv *priv = adapter->algo_data;
43
44 return usb_control_msg(priv->usb_dev, usb_rcvctrlpipe(priv->usb_dev, 0),
45 cmd, USB_TYPE_VENDOR | USB_RECIP_INTERFACE |
46 USB_DIR_IN, value, index, data, len, 2000);
47}
48
49static int osif_usb_write(struct i2c_adapter *adapter, int cmd,
50 int value, int index, void *data, int len)
51{
52
53 struct osif_priv *priv = adapter->algo_data;
54
55 return usb_control_msg(priv->usb_dev, usb_sndctrlpipe(priv->usb_dev, 0),
56 cmd, USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
57 value, index, data, len, 2000);
58}
59
60static int osif_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
61 int num)
62{
63 struct osif_priv *priv = adapter->algo_data;
64 struct i2c_msg *pmsg;
65 int ret = 0;
66 int i, cmd;
67
68 for (i = 0; ret >= 0 && i < num; i++) {
69 pmsg = &msgs[i];
70
71 if (pmsg->flags & I2C_M_RD) {
72 cmd = OSIFI2C_READ;
73
74 ret = osif_usb_read(adapter, cmd, pmsg->flags,
75 pmsg->addr, pmsg->buf,
76 pmsg->len);
77 if (ret != pmsg->len) {
78 dev_err(&adapter->dev, "failure reading data\n");
79 return -EREMOTEIO;
80 }
81 } else {
82 cmd = OSIFI2C_WRITE;
83
84 ret = osif_usb_write(adapter, cmd, pmsg->flags,
85 pmsg->addr, pmsg->buf, pmsg->len);
86 if (ret != pmsg->len) {
87 dev_err(&adapter->dev, "failure writing data\n");
88 return -EREMOTEIO;
89 }
90 }
91
92 ret = osif_usb_read(adapter, OSIFI2C_STOP, 0, 0, NULL, 0);
93 if (ret) {
94 dev_err(&adapter->dev, "failure sending STOP\n");
95 return -EREMOTEIO;
96 }
97
98 /* read status */
99 ret = osif_usb_read(adapter, OSIFI2C_STATUS, 0, 0,
100 &priv->status, 1);
101 if (ret != 1) {
102 dev_err(&adapter->dev, "failure reading status\n");
103 return -EREMOTEIO;
104 }
105
106 if (priv->status != STATUS_ADDRESS_ACK) {
107 dev_dbg(&adapter->dev, "status = %d\n", priv->status);
108 return -EREMOTEIO;
109 }
110 }
111
112 return i;
113}
114
115static u32 osif_func(struct i2c_adapter *adapter)
116{
117 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
118}
119
120static struct i2c_algorithm osif_algorithm = {
121 .master_xfer = osif_xfer,
122 .functionality = osif_func,
123};
124
125#define USB_OSIF_VENDOR_ID 0x1964
126#define USB_OSIF_PRODUCT_ID 0x0001
127
128static struct usb_device_id osif_table[] = {
129 { USB_DEVICE(USB_OSIF_VENDOR_ID, USB_OSIF_PRODUCT_ID) },
130 { }
131};
132MODULE_DEVICE_TABLE(usb, osif_table);
133
134static int osif_probe(struct usb_interface *interface,
135 const struct usb_device_id *id)
136{
137 int ret;
138 struct osif_priv *priv;
139 u16 version;
140
141 priv = devm_kzalloc(&interface->dev, sizeof(*priv), GFP_KERNEL);
142 if (!priv)
143 return -ENOMEM;
144
145 priv->usb_dev = usb_get_dev(interface_to_usbdev(interface));
146 priv->interface = interface;
147
148 usb_set_intfdata(interface, priv);
149
150 priv->adapter.owner = THIS_MODULE;
151 priv->adapter.class = I2C_CLASS_HWMON;
152 priv->adapter.algo = &osif_algorithm;
153 priv->adapter.algo_data = priv;
154 snprintf(priv->adapter.name, sizeof(priv->adapter.name),
155 "OSIF at bus %03d device %03d",
156 priv->usb_dev->bus->busnum, priv->usb_dev->devnum);
157
158 /*
159 * Set bus frequency. The frequency is:
160 * 120,000,000 / ( 16 + 2 * div * 4^prescale).
161 * Using dev = 52, prescale = 0 give 100KHz */
162 ret = osif_usb_read(&priv->adapter, OSIFI2C_SET_BIT_RATE, 52, 0,
163 NULL, 0);
164 if (ret) {
165 dev_err(&interface->dev, "failure sending bit rate");
166 usb_put_dev(priv->usb_dev);
167 return ret;
168 }
169
170 i2c_add_adapter(&(priv->adapter));
171
172 version = le16_to_cpu(priv->usb_dev->descriptor.bcdDevice);
173 dev_info(&interface->dev,
174 "version %x.%02x found at bus %03d address %03d",
175 version >> 8, version & 0xff,
176 priv->usb_dev->bus->busnum, priv->usb_dev->devnum);
177
178 return 0;
179}
180
181static void osif_disconnect(struct usb_interface *interface)
182{
183 struct osif_priv *priv = usb_get_intfdata(interface);
184
185 i2c_del_adapter(&(priv->adapter));
186 usb_set_intfdata(interface, NULL);
187 usb_put_dev(priv->usb_dev);
188}
189
190static struct usb_driver osif_driver = {
191 .name = "RobotFuzz Open Source InterFace, OSIF",
192 .probe = osif_probe,
193 .disconnect = osif_disconnect,
194 .id_table = osif_table,
195};
196
197module_usb_driver(osif_driver);
198
199MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
200MODULE_AUTHOR("Barry Carter <barry.carter@robotfuzz.com>");
201MODULE_DESCRIPTION("RobotFuzz OSIF driver");
202MODULE_LICENSE("GPL v2");