1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 /*
3 * Userspace ABI for Counter character devices
4 * Copyright (C) 2020 William Breathitt Gray
5 */
6 #ifndef _UAPI_COUNTER_H_
7 #define _UAPI_COUNTER_H_
8
9 #include <linux/ioctl.h>
10 #include <linux/types.h>
11
12 /* Component type definitions */
13 enum counter_component_type {
14 COUNTER_COMPONENT_NONE,
15 COUNTER_COMPONENT_SIGNAL,
16 COUNTER_COMPONENT_COUNT,
17 COUNTER_COMPONENT_FUNCTION,
18 COUNTER_COMPONENT_SYNAPSE_ACTION,
19 COUNTER_COMPONENT_EXTENSION,
20 };
21
22 /* Component scope definitions */
23 enum counter_scope {
24 COUNTER_SCOPE_DEVICE,
25 COUNTER_SCOPE_SIGNAL,
26 COUNTER_SCOPE_COUNT,
27 };
28
29 /**
30 * struct counter_component - Counter component identification
31 * @type: component type (one of enum counter_component_type)
32 * @scope: component scope (one of enum counter_scope)
33 * @parent: parent ID (matching the ID suffix of the respective parent sysfs
34 * path as described by the ABI documentation file
35 * Documentation/ABI/testing/sysfs-bus-counter)
36 * @id: component ID (matching the ID provided by the respective *_component_id
37 * sysfs attribute of the desired component)
38 *
39 * For example, if the Count 2 ceiling extension of Counter device 4 is desired,
40 * set type equal to COUNTER_COMPONENT_EXTENSION, scope equal to
41 * COUNTER_SCOPE_COUNT, parent equal to 2, and id equal to the value provided by
42 * the respective /sys/bus/counter/devices/counter4/count2/ceiling_component_id
43 * sysfs attribute.
44 */
45 struct counter_component {
46 __u8 type;
47 __u8 scope;
48 __u8 parent;
49 __u8 id;
50 };
51
52 /* Event type definitions */
53 enum counter_event_type {
54 /* Count value increased past ceiling */
55 COUNTER_EVENT_OVERFLOW,
56 /* Count value decreased past floor */
57 COUNTER_EVENT_UNDERFLOW,
58 /* Count value increased past ceiling, or decreased past floor */
59 COUNTER_EVENT_OVERFLOW_UNDERFLOW,
60 /* Count value reached threshold */
61 COUNTER_EVENT_THRESHOLD,
62 /* Index signal detected */
63 COUNTER_EVENT_INDEX,
64 /* State of counter is changed */
65 COUNTER_EVENT_CHANGE_OF_STATE,
66 /* Count value captured */
67 COUNTER_EVENT_CAPTURE,
68 };
69
70 /**
71 * struct counter_watch - Counter component watch configuration
72 * @component: component to watch when event triggers
73 * @event: event that triggers (one of enum counter_event_type)
74 * @channel: event channel (typically 0 unless the device supports concurrent
75 * events of the same type)
76 */
77 struct counter_watch {
78 struct counter_component component;
79 __u8 event;
80 __u8 channel;
81 };
82
83 /*
84 * Queues a Counter watch for the specified event.
85 *
86 * The queued watches will not be applied until COUNTER_ENABLE_EVENTS_IOCTL is
87 * called.
88 */
89 #define COUNTER_ADD_WATCH_IOCTL _IOW(0x3E, 0x00, struct counter_watch)
90 /*
91 * Enables monitoring the events specified by the Counter watches that were
92 * queued by COUNTER_ADD_WATCH_IOCTL.
93 *
94 * If events are already enabled, the new set of watches replaces the old one.
95 * Calling this ioctl also has the effect of clearing the queue of watches added
96 * by COUNTER_ADD_WATCH_IOCTL.
97 */
98 #define COUNTER_ENABLE_EVENTS_IOCTL _IO(0x3E, 0x01)
99 /*
100 * Stops monitoring the previously enabled events.
101 */
102 #define COUNTER_DISABLE_EVENTS_IOCTL _IO(0x3E, 0x02)
103
104 /**
105 * struct counter_event - Counter event data
106 * @timestamp: best estimate of time of event occurrence, in nanoseconds
107 * @value: component value
108 * @watch: component watch configuration
109 * @status: return status (system error number)
110 */
111 struct counter_event {
112 __aligned_u64 timestamp;
113 __aligned_u64 value;
114 struct counter_watch watch;
115 __u8 status;
116 };
117
118 /* Count direction values */
119 enum counter_count_direction {
120 COUNTER_COUNT_DIRECTION_FORWARD,
121 COUNTER_COUNT_DIRECTION_BACKWARD,
122 };
123
124 /* Count mode values */
125 enum counter_count_mode {
126 COUNTER_COUNT_MODE_NORMAL,
127 COUNTER_COUNT_MODE_RANGE_LIMIT,
128 COUNTER_COUNT_MODE_NON_RECYCLE,
129 COUNTER_COUNT_MODE_MODULO_N,
130 COUNTER_COUNT_MODE_INTERRUPT_ON_TERMINAL_COUNT,
131 COUNTER_COUNT_MODE_HARDWARE_RETRIGGERABLE_ONESHOT,
132 COUNTER_COUNT_MODE_RATE_GENERATOR,
133 COUNTER_COUNT_MODE_SQUARE_WAVE_MODE,
134 COUNTER_COUNT_MODE_SOFTWARE_TRIGGERED_STROBE,
135 COUNTER_COUNT_MODE_HARDWARE_TRIGGERED_STROBE,
136 };
137
138 /* Count function values */
139 enum counter_function {
140 COUNTER_FUNCTION_INCREASE,
141 COUNTER_FUNCTION_DECREASE,
142 COUNTER_FUNCTION_PULSE_DIRECTION,
143 COUNTER_FUNCTION_QUADRATURE_X1_A,
144 COUNTER_FUNCTION_QUADRATURE_X1_B,
145 COUNTER_FUNCTION_QUADRATURE_X2_A,
146 COUNTER_FUNCTION_QUADRATURE_X2_B,
147 COUNTER_FUNCTION_QUADRATURE_X4,
148 };
149
150 /* Signal values */
151 enum counter_signal_level {
152 COUNTER_SIGNAL_LEVEL_LOW,
153 COUNTER_SIGNAL_LEVEL_HIGH,
154 };
155
156 /* Action mode values */
157 enum counter_synapse_action {
158 COUNTER_SYNAPSE_ACTION_NONE,
159 COUNTER_SYNAPSE_ACTION_RISING_EDGE,
160 COUNTER_SYNAPSE_ACTION_FALLING_EDGE,
161 COUNTER_SYNAPSE_ACTION_BOTH_EDGES,
162 };
163
164 /* Signal polarity values */
165 enum counter_signal_polarity {
166 COUNTER_SIGNAL_POLARITY_POSITIVE,
167 COUNTER_SIGNAL_POLARITY_NEGATIVE,
168 };
169
170 #endif /* _UAPI_COUNTER_H_ */
171
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