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/ceiling_component_id
 207 What:           /sys/bus/counter/devices/counterX/countY/floor_component_id
 208 What:           /sys/bus/counter/devices/counterX/countY/count_mode_component_id
 209 What:           /sys/bus/counter/devices/counterX/countY/direction_component_id
 210 What:           /sys/bus/counter/devices/counterX/countY/enable_component_id
 211 What:           /sys/bus/counter/devices/counterX/countY/error_noise_component_id
 212 What:           /sys/bus/counter/devices/counterX/countY/prescaler_component_id
 213 What:           /sys/bus/counter/devices/counterX/countY/preset_component_id
 214 What:           /sys/bus/counter/devices/counterX/countY/preset_enable_component_id
 215 What:           /sys/bus/counter/devices/counterX/countY/signalZ_action_component_id
 216 What:           /sys/bus/counter/devices/counterX/signalY/cable_fault_component_id
 217 What:           /sys/bus/counter/devices/counterX/signalY/cable_fault_enable_component_id
 218 What:           /sys/bus/counter/devices/counterX/signalY/filter_clock_prescaler_component_id
 219 What:           /sys/bus/counter/devices/counterX/signalY/index_polarity_component_id
 220 What:           /sys/bus/counter/devices/counterX/signalY/synchronous_mode_component_id
 221 KernelVersion:  5.16
 222 Contact:        linux-iio@vger.kernel.org
 223 Description:
 224                 Read-only attribute that indicates the component ID of the
 225                 respective extension or Synapse.
 226
 227 What:           /sys/bus/counter/devices/counterX/countY/spike_filter_ns
 228 KernelVersion:  5.14
 229 Contact:        linux-iio@vger.kernel.org
 230 Description:
 231                 If the counter device supports programmable spike filter this
 232                 attribute indicates the value in nanoseconds where noise pulses
 233                 shorter or equal to configured value are ignored. Value 0 means
 234                 filter is disabled.
 235
 236 What:           /sys/bus/counter/devices/counterX/events_queue_size
 237 KernelVersion:  5.16
 238 Contact:        linux-iio@vger.kernel.org
 239 Description:
 240                 Size of the Counter events queue in number of struct
 241                 counter_event data structures. The number of elements will be
 242                 rounded-up to a power of 2.
 243
 244 What:           /sys/bus/counter/devices/counterX/name
 245 KernelVersion:  5.2
 246 Contact:        linux-iio@vger.kernel.org
 247 Description:
 248                 Read-only attribute that indicates the device-specific name of
 249                 the Counter. This should match the name of the device as it
 250                 appears in its respective datasheet.
 251
 252 What:           /sys/bus/counter/devices/counterX/num_counts
 253 KernelVersion:  5.2
 254 Contact:        linux-iio@vger.kernel.org
 255 Description:
 256                 Read-only attribute that indicates the total number of Counts
 257                 belonging to the Counter.
 258
 259 What:           /sys/bus/counter/devices/counterX/num_signals
 260 KernelVersion:  5.2
 261 Contact:        linux-iio@vger.kernel.org
 262 Description:
 263                 Read-only attribute that indicates the total number of Signals
 264                 belonging to the Counter.
 265
 266 What:           /sys/bus/counter/devices/counterX/signalY/cable_fault
 267 KernelVersion:  5.7
 268 Contact:        linux-iio@vger.kernel.org
 269 Description:
 270                 Read-only attribute that indicates whether a differential
 271                 encoder cable fault (not connected or loose wires) is detected
 272                 for the respective channel of Signal Y. Valid attribute values
 273                 are boolean. Detection must first be enabled via the
 274                 corresponding cable_fault_enable attribute.
 275
 276 What:           /sys/bus/counter/devices/counterX/signalY/cable_fault_enable
 277 KernelVersion:  5.7
 278 Contact:        linux-iio@vger.kernel.org
 279 Description:
 280                 Whether detection of differential encoder cable faults for the
 281                 respective channel of Signal Y is enabled. Valid attribute
 282                 values are boolean.
 283
 284 What:           /sys/bus/counter/devices/counterX/signalY/filter_clock_prescaler
 285 KernelVersion:  5.7
 286 Contact:        linux-iio@vger.kernel.org
 287 Description:
 288                 Filter clock factor for input Signal Y. This prescaler value
 289                 affects the inputs of both quadrature pair signals.
 290
 291 What:           /sys/bus/counter/devices/counterX/signalY/index_polarity
 292 KernelVersion:  5.2
 293 Contact:        linux-iio@vger.kernel.org
 294 Description:
 295                 Active level of index input Signal Y; irrelevant in
 296                 non-synchronous load mode.
 297
 298 What:           /sys/bus/counter/devices/counterX/signalY/index_polarity_available
 299 What:           /sys/bus/counter/devices/counterX/signalY/synchronous_mode_available
 300 KernelVersion:  5.2
 301 Contact:        linux-iio@vger.kernel.org
 302 Description:
 303                 Discrete set of available values for the respective Signal Y
 304                 configuration are listed in this file.
 305
 306 What:           /sys/bus/counter/devices/counterX/signalY/name
 307 KernelVersion:  5.2
 308 Contact:        linux-iio@vger.kernel.org
 309 Description:
 310                 Read-only attribute that indicates the device-specific name of
 311                 Signal Y. If possible, this should match the name of the
 312                 respective signal as it appears in the device datasheet.
 313
 314 What:           /sys/bus/counter/devices/counterX/signalY/signal
 315 KernelVersion:  5.2
 316 Contact:        linux-iio@vger.kernel.org
 317 Description:
 318                 Signal level state of Signal Y. The following signal level
 319                 states are available:
 320
 321                 low:
 322                         Low level state.
 323
 324                 high:
 325                         High level state.
 326
 327 What:           /sys/bus/counter/devices/counterX/signalY/synchronous_mode
 328 KernelVersion:  5.2
 329 Contact:        linux-iio@vger.kernel.org
 330 Description:
 331                 Configure the counter associated with Signal Y for
 332                 non-synchronous or synchronous load mode. Synchronous load mode
 333                 cannot be selected in non-quadrature (Pulse-Direction) clock
 334                 mode.
 335
 336                 non-synchronous:
 337                         A logic low level is the active level at this index
 338                         input. The index function (as enabled via preset_enable)
 339                         is performed directly on the active level of the index
 340                         input.
 341
 342                 synchronous:
 343                         Intended for interfacing with encoder Index output in
 344                         quadrature clock mode. The active level is configured
 345                         via index_polarity. The index function (as enabled via
 346                         preset_enable) is performed synchronously with the
 347                         quadrature clock on the active level of the index input.