Documentation/ABI/testing/sysfs-bus-counter

   1 What:           /sys/bus/counter/devices/counterX/countY/count
   2 KernelVersion:  5.2
   3 Contact:        linux-iio@vger.kernel.org
   4 Description:
   5                 Count data of Count Y represented as a string.
   6
   7 What:           /sys/bus/counter/devices/counterX/countY/ceiling
   8 KernelVersion:  5.2
   9 Contact:        linux-iio@vger.kernel.org
  10 Description:
  11                 Count value ceiling for Count Y. This is the upper limit for the
  12                 respective counter.
  13
  14 What:           /sys/bus/counter/devices/counterX/countY/floor
  15 KernelVersion:  5.2
  16 Contact:        linux-iio@vger.kernel.org
  17 Description:
  18                 Count value floor for Count Y. This is the lower limit for the
  19                 respective counter.
  20
  21 What:           /sys/bus/counter/devices/counterX/countY/count_mode
  22 KernelVersion:  5.2
  23 Contact:        linux-iio@vger.kernel.org
  24 Description:
  25                 Count mode for channel Y. The ceiling and floor values for
  26                 Count Y are used by the count mode where required. The following
  27                 count modes are available:
  28
  29                 normal:
  30                         Counting is continuous in either direction.
  31
  32                 range limit:
  33                         An upper or lower limit is set, mimicking limit switches
  34                         in the mechanical counterpart. The upper limit is set to
  35                         the Count Y ceiling value, while the lower limit is set
  36                         to the Count Y floor value. The counter freezes at
  37                         count = ceiling when counting up, and at count = floor
  38                         when counting down. At either of these limits, the
  39                         counting is resumed only when the count direction is
  40                         reversed.
  41
  42                 non-recycle:
  43                         The counter is disabled whenever a counter overflow or
  44                         underflow takes place. The counter is re-enabled when a
  45                         new count value is loaded to the counter via a preset
  46                         operation or direct write.
  47
  48                 modulo-n:
  49                         A count value boundary is set between the Count Y floor
  50                         value and the Count Y ceiling value. The counter is
  51                         reset to the Count Y floor value at count = ceiling when
  52                         counting up, while the counter is set to the Count Y
  53                         ceiling value at count = floor when counting down; the
  54                         counter does not freeze at the boundary points, but
  55                         counts continuously throughout.
  56
  57 What:           /sys/bus/counter/devices/counterX/countY/count_mode_available
  58 What:           /sys/bus/counter/devices/counterX/countY/error_noise_available
  59 What:           /sys/bus/counter/devices/counterX/countY/function_available
  60 What:           /sys/bus/counter/devices/counterX/countY/signalZ_action_available
  61 KernelVersion:  5.2
  62 Contact:        linux-iio@vger.kernel.org
  63 Description:
  64                 Discrete set of available values for the respective Count Y
  65                 configuration are listed in this file. Values are delimited by
  66                 newline characters.
  67
  68 What:           /sys/bus/counter/devices/counterX/countY/direction
  69 KernelVersion:  5.2
  70 Contact:        linux-iio@vger.kernel.org
  71 Description:
  72                 Read-only attribute that indicates the count direction of Count
  73                 Y. Two count directions are available: forward and backward.
  74
  75                 Some counter devices are able to determine the direction of
  76                 their counting. For example, quadrature encoding counters can
  77                 determine the direction of movement by evaluating the leading
  78                 phase of the respective A and B quadrature encoding signals.
  79                 This attribute exposes such count directions.
  80
  81 What:           /sys/bus/counter/devices/counterX/countY/enable
  82 KernelVersion:  5.2
  83 Contact:        linux-iio@vger.kernel.org
  84 Description:
  85                 Whether channel Y counter is enabled. Valid attribute values are
  86                 boolean.
  87
  88                 This attribute is intended to serve as a pause/unpause mechanism
  89                 for Count Y. Suppose a counter device is used to count the total
  90                 movement of a conveyor belt: this attribute allows an operator
  91                 to temporarily pause the counter, service the conveyor belt,
  92                 and then finally unpause the counter to continue where it had
  93                 left off.
  94
  95 What:           /sys/bus/counter/devices/counterX/countY/error_noise
  96 KernelVersion:  5.2
  97 Contact:        linux-iio@vger.kernel.org
  98 Description:
  99                 Read-only attribute that indicates whether excessive noise is
 100                 present at the channel Y counter inputs.
 101
 102 What:           /sys/bus/counter/devices/counterX/countY/function
 103 KernelVersion:  5.2
 104 Contact:        linux-iio@vger.kernel.org
 105 Description:
 106                 Count function mode of Count Y; count function evaluation is
 107                 triggered by conditions specified by the Count Y signalZ_action
 108                 attributes. The following count functions are available:
 109
 110                 increase:
 111                         Accumulated count is incremented.
 112
 113                 decrease:
 114                         Accumulated count is decremented.
 115
 116                 pulse-direction:
 117                         Rising edges on signal A updates the respective count.
 118                         The input level of signal B determines direction.
 119
 120                 quadrature x1 a:
 121                         If direction is forward, rising edges on quadrature pair
 122                         signal A updates the respective count; if the direction
 123                         is backward, falling edges on quadrature pair signal A
 124                         updates the respective count. Quadrature encoding
 125                         determines the direction.
 126
 127                 quadrature x1 b:
 128                         If direction is forward, rising edges on quadrature pair
 129                         signal B updates the respective count; if the direction
 130                         is backward, falling edges on quadrature pair signal B
 131                         updates the respective count. Quadrature encoding
 132                         determines the direction.
 133
 134                 quadrature x2 a:
 135                         Any state transition on quadrature pair signal A updates
 136                         the respective count. Quadrature encoding determines the
 137                         direction.
 138
 139                 quadrature x2 b:
 140                         Any state transition on quadrature pair signal B updates
 141                         the respective count. Quadrature encoding determines the
 142                         direction.
 143
 144                 quadrature x4:
 145                         Any state transition on either quadrature pair signals
 146                         updates the respective count. Quadrature encoding
 147                         determines the direction.
 148
 149 What:           /sys/bus/counter/devices/counterX/countY/name
 150 KernelVersion:  5.2
 151 Contact:        linux-iio@vger.kernel.org
 152 Description:
 153                 Read-only attribute that indicates the device-specific name of
 154                 Count Y. If possible, this should match the name of the
 155                 respective channel as it appears in the device datasheet.
 156
 157 What:           /sys/bus/counter/devices/counterX/countY/preset
 158 KernelVersion:  5.2
 159 Contact:        linux-iio@vger.kernel.org
 160 Description:
 161                 If the counter device supports preset registers -- registers
 162                 used to load counter channels to a set count upon device-defined
 163                 preset operation trigger events -- the preset count for channel
 164                 Y is provided by this attribute.
 165
 166 What:           /sys/bus/counter/devices/counterX/countY/preset_enable
 167 KernelVersion:  5.2
 168 Contact:        linux-iio@vger.kernel.org
 169 Description:
 170                 Whether channel Y counter preset operation is enabled. Valid
 171                 attribute values are boolean.
 172
 173 What:           /sys/bus/counter/devices/counterX/countY/signalZ_action
 174 KernelVersion:  5.2
 175 Contact:        linux-iio@vger.kernel.org
 176 Description:
 177                 Action mode of Count Y for Signal Z. This attribute indicates
 178                 the condition of Signal Z that triggers the count function
 179                 evaluation for Count Y. The following action modes are
 180                 available:
 181
 182                 none:
 183                         Signal does not trigger the count function. In
 184                         Pulse-Direction count function mode, this Signal is
 185                         evaluated as Direction.
 186
 187                 rising edge:
 188                         Low state transitions to high state.
 189
 190                 falling edge:
 191                         High state transitions to low state.
 192
 193                 both edges:
 194                         Any state transition.
 195
 196 What:           /sys/bus/counter/devices/counterX/name
 197 KernelVersion:  5.2
 198 Contact:        linux-iio@vger.kernel.org
 199 Description:
 200                 Read-only attribute that indicates the device-specific name of
 201                 the Counter. This should match the name of the device as it
 202                 appears in its respective datasheet.
 203
 204 What:           /sys/bus/counter/devices/counterX/num_counts
 205 KernelVersion:  5.2
 206 Contact:        linux-iio@vger.kernel.org
 207 Description:
 208                 Read-only attribute that indicates the total number of Counts
 209                 belonging to the Counter.
 210
 211 What:           /sys/bus/counter/devices/counterX/num_signals
 212 KernelVersion:  5.2
 213 Contact:        linux-iio@vger.kernel.org
 214 Description:
 215                 Read-only attribute that indicates the total number of Signals
 216                 belonging to the Counter.
 217
 218 What:           /sys/bus/counter/devices/counterX/signalY/signal
 219 KernelVersion:  5.2
 220 Contact:        linux-iio@vger.kernel.org
 221 Description:
 222                 Signal data of Signal Y represented as a string.
 223
 224 What:           /sys/bus/counter/devices/counterX/signalY/name
 225 KernelVersion:  5.2
 226 Contact:        linux-iio@vger.kernel.org
 227 Description:
 228                 Read-only attribute that indicates the device-specific name of
 229                 Signal Y. If possible, this should match the name of the
 230                 respective signal as it appears in the device datasheet.