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/prescaler_available
  61 What:           /sys/bus/counter/devices/counterX/countY/signalZ_action_available
  62 KernelVersion:  5.2
  63 Contact:        linux-iio@vger.kernel.org
  64 Description:
  65                 Discrete set of available values for the respective Count Y
  66                 configuration are listed in this file. Values are delimited by
  67                 newline characters.
  68
  69 What:           /sys/bus/counter/devices/counterX/countY/direction
  70 KernelVersion:  5.2
  71 Contact:        linux-iio@vger.kernel.org
  72 Description:
  73                 Read-only attribute that indicates the count direction of Count
  74                 Y. Two count directions are available: forward and backward.
  75
  76                 Some counter devices are able to determine the direction of
  77                 their counting. For example, quadrature encoding counters can
  78                 determine the direction of movement by evaluating the leading
  79                 phase of the respective A and B quadrature encoding signals.
  80                 This attribute exposes such count directions.
  81
  82 What:           /sys/bus/counter/devices/counterX/countY/enable
  83 KernelVersion:  5.2
  84 Contact:        linux-iio@vger.kernel.org
  85 Description:
  86                 Whether channel Y counter is enabled. Valid attribute values are
  87                 boolean.
  88
  89                 This attribute is intended to serve as a pause/unpause mechanism
  90                 for Count Y. Suppose a counter device is used to count the total
  91                 movement of a conveyor belt: this attribute allows an operator
  92                 to temporarily pause the counter, service the conveyor belt,
  93                 and then finally unpause the counter to continue where it had
  94                 left off.
  95
  96 What:           /sys/bus/counter/devices/counterX/countY/error_noise
  97 KernelVersion:  5.2
  98 Contact:        linux-iio@vger.kernel.org
  99 Description:
 100                 Read-only attribute that indicates whether excessive noise is
 101                 present at the channel Y counter inputs.
 102
 103 What:           /sys/bus/counter/devices/counterX/countY/function
 104 KernelVersion:  5.2
 105 Contact:        linux-iio@vger.kernel.org
 106 Description:
 107                 Count function mode of Count Y; count function evaluation is
 108                 triggered by conditions specified by the Count Y signalZ_action
 109                 attributes. The following count functions are available:
 110
 111                 increase:
 112                         Accumulated count is incremented.
 113
 114                 decrease:
 115                         Accumulated count is decremented.
 116
 117                 pulse-direction:
 118                         Rising edges on signal A updates the respective count.
 119                         The input level of signal B determines direction.
 120
 121                 quadrature x1 a:
 122                         If direction is forward, rising edges on quadrature pair
 123                         signal A updates the respective count; if the direction
 124                         is backward, falling edges on quadrature pair signal A
 125                         updates the respective count. Quadrature encoding
 126                         determines the direction.
 127
 128                 quadrature x1 b:
 129                         If direction is forward, rising edges on quadrature pair
 130                         signal B updates the respective count; if the direction
 131                         is backward, falling edges on quadrature pair signal B
 132                         updates the respective count. Quadrature encoding
 133                         determines the direction.
 134
 135                 quadrature x2 a:
 136                         Any state transition on quadrature pair signal A updates
 137                         the respective count. Quadrature encoding determines the
 138                         direction.
 139
 140                 quadrature x2 b:
 141                         Any state transition on quadrature pair signal B updates
 142                         the respective count. Quadrature encoding determines the
 143                         direction.
 144
 145                 quadrature x4:
 146                         Any state transition on either quadrature pair signals
 147                         updates the respective count. Quadrature encoding
 148                         determines the direction.
 149
 150 What:           /sys/bus/counter/devices/counterX/countY/name
 151 KernelVersion:  5.2
 152 Contact:        linux-iio@vger.kernel.org
 153 Description:
 154                 Read-only attribute that indicates the device-specific name of
 155                 Count Y. If possible, this should match the name of the
 156                 respective channel as it appears in the device datasheet.
 157
 158 What:           /sys/bus/counter/devices/counterX/countY/prescaler
 159 KernelVersion:  5.2
 160 Contact:        linux-iio@vger.kernel.org
 161 Description:
 162                 Configure the prescaler value associated with Count Y.
 163                 On the FlexTimer, the counter clock source passes through a
 164                 prescaler (i.e. a counter). This acts like a clock
 165                 divider.
 166
 167 What:           /sys/bus/counter/devices/counterX/countY/preset
 168 KernelVersion:  5.2
 169 Contact:        linux-iio@vger.kernel.org
 170 Description:
 171                 If the counter device supports preset registers -- registers
 172                 used to load counter channels to a set count upon device-defined
 173                 preset operation trigger events -- the preset count for channel
 174                 Y is provided by this attribute.
 175
 176 What:           /sys/bus/counter/devices/counterX/countY/preset_enable
 177 KernelVersion:  5.2
 178 Contact:        linux-iio@vger.kernel.org
 179 Description:
 180                 Whether channel Y counter preset operation is enabled. Valid
 181                 attribute values are boolean.
 182
 183 What:           /sys/bus/counter/devices/counterX/countY/signalZ_action
 184 KernelVersion:  5.2
 185 Contact:        linux-iio@vger.kernel.org
 186 Description:
 187                 Action mode of Count Y for Signal Z. This attribute indicates
 188                 the condition of Signal Z that triggers the count function
 189                 evaluation for Count Y. The following action modes are
 190                 available:
 191
 192                 none:
 193                         Signal does not trigger the count function. In
 194                         Pulse-Direction count function mode, this Signal is
 195                         evaluated as Direction.
 196
 197                 rising edge:
 198                         Low state transitions to high state.
 199
 200                 falling edge:
 201                         High state transitions to low state.
 202
 203                 both edges:
 204                         Any state transition.
 205
 206 What:           /sys/bus/counter/devices/counterX/countY/spike_filter_ns
 207 KernelVersion:  5.14
 208 Contact:        linux-iio@vger.kernel.org
 209 Description:
 210                 If the counter device supports programmable spike filter this
 211                 attribute indicates the value in nanoseconds where noise pulses
 212                 shorter or equal to configured value are ignored. Value 0 means
 213                 filter is disabled.
 214
 215 What:           /sys/bus/counter/devices/counterX/name
 216 KernelVersion:  5.2
 217 Contact:        linux-iio@vger.kernel.org
 218 Description:
 219                 Read-only attribute that indicates the device-specific name of
 220                 the Counter. This should match the name of the device as it
 221                 appears in its respective datasheet.
 222
 223 What:           /sys/bus/counter/devices/counterX/num_counts
 224 KernelVersion:  5.2
 225 Contact:        linux-iio@vger.kernel.org
 226 Description:
 227                 Read-only attribute that indicates the total number of Counts
 228                 belonging to the Counter.
 229
 230 What:           /sys/bus/counter/devices/counterX/num_signals
 231 KernelVersion:  5.2
 232 Contact:        linux-iio@vger.kernel.org
 233 Description:
 234                 Read-only attribute that indicates the total number of Signals
 235                 belonging to the Counter.
 236
 237 What:           /sys/bus/counter/devices/counterX/signalY/cable_fault
 238 KernelVersion:  5.7
 239 Contact:        linux-iio@vger.kernel.org
 240 Description:
 241                 Read-only attribute that indicates whether a differential
 242                 encoder cable fault (not connected or loose wires) is detected
 243                 for the respective channel of Signal Y. Valid attribute values
 244                 are boolean. Detection must first be enabled via the
 245                 corresponding cable_fault_enable attribute.
 246
 247 What:           /sys/bus/counter/devices/counterX/signalY/cable_fault_enable
 248 KernelVersion:  5.7
 249 Contact:        linux-iio@vger.kernel.org
 250 Description:
 251                 Whether detection of differential encoder cable faults for the
 252                 respective channel of Signal Y is enabled. Valid attribute
 253                 values are boolean.
 254
 255 What:           /sys/bus/counter/devices/counterX/signalY/filter_clock_prescaler
 256 KernelVersion:  5.7
 257 Contact:        linux-iio@vger.kernel.org
 258 Description:
 259                 Filter clock factor for input Signal Y. This prescaler value
 260                 affects the inputs of both quadrature pair signals.
 261
 262 What:           /sys/bus/counter/devices/counterX/signalY/index_polarity
 263 KernelVersion:  5.2
 264 Contact:        linux-iio@vger.kernel.org
 265 Description:
 266                 Active level of index input Signal Y; irrelevant in
 267                 non-synchronous load mode.
 268
 269 What:           /sys/bus/counter/devices/counterX/signalY/index_polarity_available
 270 What:           /sys/bus/counter/devices/counterX/signalY/synchronous_mode_available
 271 KernelVersion:  5.2
 272 Contact:        linux-iio@vger.kernel.org
 273 Description:
 274                 Discrete set of available values for the respective Signal Y
 275                 configuration are listed in this file.
 276
 277 What:           /sys/bus/counter/devices/counterX/signalY/name
 278 KernelVersion:  5.2
 279 Contact:        linux-iio@vger.kernel.org
 280 Description:
 281                 Read-only attribute that indicates the device-specific name of
 282                 Signal Y. If possible, this should match the name of the
 283                 respective signal as it appears in the device datasheet.
 284
 285 What:           /sys/bus/counter/devices/counterX/signalY/signal
 286 KernelVersion:  5.2
 287 Contact:        linux-iio@vger.kernel.org
 288 Description:
 289                 Signal data of Signal Y represented as a string.
 290
 291 What:           /sys/bus/counter/devices/counterX/signalY/synchronous_mode
 292 KernelVersion:  5.2
 293 Contact:        linux-iio@vger.kernel.org
 294 Description:
 295                 Configure the counter associated with Signal Y for
 296                 non-synchronous or synchronous load mode. Synchronous load mode
 297                 cannot be selected in non-quadrature (Pulse-Direction) clock
 298                 mode.
 299
 300                 non-synchronous:
 301                         A logic low level is the active level at this index
 302                         input. The index function (as enabled via preset_enable)
 303                         is performed directly on the active level of the index
 304                         input.
 305
 306                 synchronous:
 307                         Intended for interfacing with encoder Index output in
 308                         quadrature clock mode. The active level is configured
 309                         via index_polarity. The index function (as enabled via
 310                         preset_enable) is performed synchronously with the
 311                         quadrature clock on the active level of the index input.