Merge tag 'spi-fix-v5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
[linux-2.6-microblaze.git] / Documentation / ABI / testing / sysfs-bus-iio-counter-104-quad-8
1 What:           /sys/bus/iio/devices/iio:deviceX/in_count_count_mode_available
2 What:           /sys/bus/iio/devices/iio:deviceX/in_count_noise_error_available
3 What:           /sys/bus/iio/devices/iio:deviceX/in_count_quadrature_mode_available
4 What:           /sys/bus/iio/devices/iio:deviceX/in_index_index_polarity_available
5 What:           /sys/bus/iio/devices/iio:deviceX/in_index_synchronous_mode_available
6 KernelVersion:  4.10
7 Contact:        linux-iio@vger.kernel.org
8 Description:
9                 This interface is deprecated; please use the Counter subsystem.
10
11                 Discrete set of available values for the respective counter
12                 configuration are listed in this file.
13
14 What:           /sys/bus/iio/devices/iio:deviceX/in_countY_count_mode
15 KernelVersion:  4.10
16 Contact:        linux-iio@vger.kernel.org
17 Description:
18                 This interface is deprecated; please use the Counter subsystem.
19
20                 Count mode for channel Y. Four count modes are available:
21                 normal, range limit, non-recycle, and modulo-n. The preset value
22                 for channel Y is used by the count mode where required.
23
24                 Normal:
25                         Counting is continuous in either direction.
26
27                 Range Limit:
28                         An upper or lower limit is set, mimicking limit switches
29                         in the mechanical counterpart. The upper limit is set to
30                         the preset value, while the lower limit is set to 0. The
31                         counter freezes at count = preset when counting up, and
32                         at count = 0 when counting down. At either of these
33                         limits, the counting is resumed only when the count
34                         direction is reversed.
35
36                 Non-recycle:
37                         Counter is disabled whenever a 24-bit count overflow or
38                         underflow takes place. The counter is re-enabled when a
39                         new count value is loaded to the counter via a preset
40                         operation or write to raw.
41
42                 Modulo-N:
43                         A count boundary is set between 0 and the preset value.
44                         The counter is reset to 0 at count = preset when
45                         counting up, while the counter is set to the preset
46                         value at count = 0 when counting down; the counter does
47                         not freeze at the bundary points, but counts
48                         continuously throughout.
49
50 What:           /sys/bus/iio/devices/iio:deviceX/in_countY_noise_error
51 KernelVersion:  4.10
52 Contact:        linux-iio@vger.kernel.org
53 Description:
54                 This interface is deprecated; please use the Counter subsystem.
55
56                 Read-only attribute that indicates whether excessive noise is
57                 present at the channel Y count inputs in quadrature clock mode;
58                 irrelevant in non-quadrature clock mode.
59
60 What:           /sys/bus/iio/devices/iio:deviceX/in_countY_preset
61 KernelVersion:  4.10
62 Contact:        linux-iio@vger.kernel.org
63 Description:
64                 This interface is deprecated; please use the Counter subsystem.
65
66                 If the counter device supports preset registers, the preset
67                 count for channel Y is provided by this attribute.
68
69 What:           /sys/bus/iio/devices/iio:deviceX/in_countY_quadrature_mode
70 KernelVersion:  4.10
71 Contact:        linux-iio@vger.kernel.org
72 Description:
73                 This interface is deprecated; please use the Counter subsystem.
74
75                 Configure channel Y counter for non-quadrature or quadrature
76                 clock mode. Selecting non-quadrature clock mode will disable
77                 synchronous load mode. In quadrature clock mode, the channel Y
78                 scale attribute selects the encoder phase division (scale of 1
79                 selects full-cycle, scale of 0.5 selects half-cycle, scale of
80                 0.25 selects quarter-cycle) processed by the channel Y counter.
81
82                 Non-quadrature:
83                         The filter and decoder circuit are bypassed. Encoder A
84                         input serves as the count input and B as the UP/DOWN
85                         direction control input, with B = 1 selecting UP Count
86                         mode and B = 0 selecting Down Count mode.
87
88                 Quadrature:
89                         Encoder A and B inputs are digitally filtered and
90                         decoded for UP/DN clock.
91
92 What:           /sys/bus/iio/devices/iio:deviceX/in_countY_set_to_preset_on_index
93 KernelVersion:  4.10
94 Contact:        linux-iio@vger.kernel.org
95 Description:
96                 This interface is deprecated; please use the Counter subsystem.
97
98                 Whether to set channel Y counter with channel Y preset value
99                 when channel Y index input is active, or continuously count.
100                 Valid attribute values are boolean.
101
102 What:           /sys/bus/iio/devices/iio:deviceX/in_indexY_index_polarity
103 KernelVersion:  4.10
104 Contact:        linux-iio@vger.kernel.org
105 Description:
106                 This interface is deprecated; please use the Counter subsystem.
107
108                 Active level of channel Y index input; irrelevant in
109                 non-synchronous load mode.
110
111 What:           /sys/bus/iio/devices/iio:deviceX/in_indexY_synchronous_mode
112 KernelVersion:  4.10
113 Contact:        linux-iio@vger.kernel.org
114 Description:
115                 This interface is deprecated; please use the Counter subsystem.
116
117                 Configure channel Y counter for non-synchronous or synchronous
118                 load mode. Synchronous load mode cannot be selected in
119                 non-quadrature clock mode.
120
121                 Non-synchronous:
122                         A logic low level is the active level at this index
123                         input. The index function (as enabled via
124                         set_to_preset_on_index) is performed directly on the
125                         active level of the index input.
126
127                 Synchronous:
128                         Intended for interfacing with encoder Index output in
129                         quadrature clock mode. The active level is configured
130                         via index_polarity. The index function (as enabled via
131                         set_to_preset_on_index) is performed synchronously with
132                         the quadrature clock on the active level of the index
133                         input.