1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
|
/*
* Copyright (C) 1995 Advanced RISC Machines Limited. All rights reserved.
*
* This software may be freely used, copied, modified, and distributed
* provided that the above copyright notice is preserved in all copies of the
* software.
*/
/* -*-C-*-
*
* $Revision: 1.2 $
* $Date: 2003/01/16 10:40:13 $
*
*
* Project: ANGEL
*
* Title: Definitions for device driver interface.
*/
#ifndef angsd_drivers_h
#define angsd_drivers_h
#include "rxtx.h"
#ifndef __cplusplus
typedef struct DeviceDescr DeviceDescr;
typedef struct DriverCall DriverCall;
#endif
/*
* used to pass packets across the driver interface
*/
struct DriverCall
{
struct data_packet dc_packet;
void *dc_context;
};
/*
* used to describe a device driver
*/
struct DeviceDescr
{
char *DeviceName;
int (*DeviceOpen)(const char *name, const char *arg);
int (*DeviceMatch)(const char *name, const char *arg);
void (*DeviceClose)(void);
int (*DeviceRead)(DriverCall *dc, bool block);
int (*DeviceWrite)(DriverCall *dc);
int (*DeviceIoctl)(const int opcode, void *args);
void *SwitcherState; /* used by switcher interface */
};
/*
* Function: DeviceOpen
*
* Purpose: Open a communications device
*
* Pre-conditions: No previous open is still active
*
* Params:
* Input: name Identifies which device to open. This can either be
* a host specific identifier (e.g. "/dev/ttya",
* "COM1:"), or a number which is used to refer to
* `standard' interfaces, so "1" would be the first host
* interface, "2" the second, and so on.
*
* arg Driver specific arguments. For example, some serial
* drivers accept speed and control arguments such as
* "9600" or "19200/NO_BREAK". These arguments are
* completely free-form: it is the individual drivers
* which do the necessary interpretation.
*
* Returns:
* OK: 0
* Error: -1
*/
extern int DeviceOpen(const char *name, const char *arg);
/*
* Function: DeviceMatch
*
* Purpose: Check whether parameters are OK to be passed to DeviceOpen
*
* Params:
* Input: name Identifies which device to open. This can either be
* a host specific identifier (e.g. "/dev/ttya",
* "COM1:"), or a number which is used to refer to
* `standard' interfaces, so "1" would be the first host
* interface, "2" the second, and so on.
*
* arg Driver specific arguments. For example, some serial
* drivers accept speed and control arguments such as
* "9600" or "19200/NO_BREAK". These arguments are
* completely free-form: it is the individual drivers
* which do the necessary interpretation.
*
* Returns:
* OK: 0
* Error: -1
*/
extern int DeviceMatch(const char *name, const char *arg);
/*
* Function: DeviceClose
*
* Purpose: Close a communications device
*
* Pre-conditions: Device must have been previously opened
*
* Params: None
*
* Returns: Nothing
*/
extern void DeviceClose(void);
/*
* Function: DeviceRead
*
* Purpose: Try to read a complete packet from a communications device.
* This read must usually be non-blocking, i.e. it should read as
* many data from the device as needed to complete the packet,
* but it should not wait if the packet is not complete, and no
* more data are currently available from the device.
* As an optimisation the read can optionally block when 'block'
* is TRUE, but only for a short time. It is acceptable for the
* 'block' parameter to be ignored in which case all reads
* should be non-blocking.
*
* Pre-conditions: Device has been opened via DeviceOpen()
*
* Params:
* In/Out: dc Describes the packet being read (dc->dc_packet);
* dc->dc_context is for the driver to store private
* context, and is guaranteed to be NULL the first
* time DeviceRead is called for a given packet.
*
* In: block If TRUE, read may safely block for a short period
* of time (say up to 20ms), to avoid high CPU load
* whilst waiting for a reply.
* If FALSE, read MUST NOT block.
*
* Returns:
* OK: 1 (packet is complete)
* 0 (packet is not yet complete)
* Error: -1 bad packet
*
* Post-conditions: should a calamatous error occur panic() will be called
*/
extern int DeviceRead(DriverCall *dc, bool block);
/*
* Function: DeviceWrite
*
* Purpose: Try to write a packet to a communications device. This write
* must be non-blocking, i.e. it should write as many data to
* the device as is immediately possible, but should not wait
* for space to send any more after that.
*
* Pre-conditions: Device has been opened via DeviceOpen()
*
* Params:
* In/Out: dc Describes the packet being written (dc->dc_packet);
* dc->dc_context is for the driver to store private
* context, and is guaranteed to be NULL the first
* time DeviceWrite is called for a given packet.
*
* Returns:
* OK: 1 (all of the packet has been written)
* 0 (some of the packet remains to be written)
* Error: -1
*/
extern int DeviceWrite(DriverCall *dc);
/*
* Function: DeviceIoctl
*
* Purpose: Perform miscellaneous driver operations
*
* Pre-conditions: Device has been open via DeviceOpen()
*
* Params:
* Input: opcode Reason code indicating the operation to perform
* In/Out: args Pointer to opcode-sensitive arguments/result space
*
* Returns:
* OK: 0
* Error: -1
*/
extern int DeviceIoctl(const int opcode, void *args);
#endif /* !defined(angsd_drivers_h) */
/* EOF drivers.h */
|
