kernel/Documentation/ABI/testing/sysfs-bus-counter, branch linux-rolling-stable

counter: Alphabetize component_id sysfs attributes Documentation list

2025-08-24T07:58:53Z

Prefer alphabetical order for the component_id sysfs attributes list in the Counter ABI Documentation file. This should make it easier for users to locate a component_id attribute in the list and its respective Documentation entry. Suggested-by: David Lechner Link: https://lore.kernel.org/r/20250615-alphabetize-component_id-doc-v1-1-4c5943b41198@kernel.org Signed-off-by: William Breathitt Gray

counter: Introduce the compare component

2025-03-10T09:00:49Z

Compare registers are used in devices to compare a counter channel against a particular count value (e.g. to check if a threshold has been reached). A macro COUNTER_COMP_COMPARE() is introduced to facilitate the creation of compare components as Count extensions. Link: https://lore.kernel.org/r/20250306-introduce-compare-component-v1-1-93993b3dca9c@kernel.org Signed-off-by: William Breathitt Gray

Documentation: ABI: sysfs-bus-counter: Fix indentation

2023-08-16T13:41:29Z

Fix the indentation of the KernelVersion, Contact, and Description in external_input_phase_clock_select_available block by replacing spaces with tabs similar to other blocks. Reported-by: Pavel Machek Closes: https://lore.kernel.org/r/ZH8D3lCobUJP2T4K@duo.ucw.cz/ Signed-off-by: Biju Das Link: https://lore.kernel.org/r/20230721151243.282435-1-biju.das.jz@bp.renesas.com/ Signed-off-by: William Breathitt Gray

counter: i8254: Introduce the Intel 8254 interface library module

2023-06-08T14:11:17Z

Exposes consumer library functions providing support for interfaces compatible with the venerable Intel 8254 Programmable Interval Timer (PIT). The Intel 8254 PIT first appeared in the early 1980s and was used initially in IBM PC compatibles. The popularity of the original Intel 825x family of chips led to many subsequent variants and clones of the interface in various chips and integrated circuits. Although still popular, interfaces compatible with the Intel 8254 PIT are nowdays typically found embedded in larger VLSI processing chips and FPGA components rather than as discrete ICs. A CONFIG_I8254 Kconfig option is introduced by this patch. Modules wanting access to these i8254 library functions should select this Kconfig option, and import the I8254 symbol namespace. Link: https://lore.kernel.org/r/f6fe32c2db9525d816ab1a01f45abad56c081652.1681665189.git.william.gray@linaro.org/ Signed-off-by: William Breathitt Gray

Documentation: ABI: sysfs-bus-counter: add cascade_counts_enable and external_input_phase_clock_select

2023-04-26T10:40:35Z

This commit adds cascade_counts_enable and external_input_phase_ clock_select items to counter ABI file. (e.g. for Renesas MTU3 hardware used for phase counting). Signed-off-by: Biju Das Reviewed-by: William Breathitt Gray Signed-off-by: Lee Jones Link: https://lore.kernel.org/r/20230330111632.169434-4-biju.das.jz@bp.renesas.com

Documentation: ABI: sysfs-bus-counter: add frequency & num_overflows items

2022-09-30T12:32:35Z

This commit adds frequency and num_overflows items to counter ABI file (e.g. for TI ECAP hardware used in capture operating mode). Signed-off-by: Julien Panis Link: https://lore.kernel.org/r/20220923142437.271328-3-jpanis@baylibre.com/ Signed-off-by: William Breathitt Gray Link: https://lore.kernel.org/r/467ae80e97c586c6bc9c453c6156ffcb5d4853d6.1664318353.git.william.gray@linaro.org Signed-off-by: Greg Kroah-Hartman

counter: Introduce the Count capture component

2022-09-30T12:32:35Z

Some devices provide a latch function to save historic Count values. This patch standardizes exposure of such functionality as Count capture components. A COUNTER_COMP_CAPTURE macro is provided for driver authors to define a capture component. A new event COUNTER_EVENT_CAPTURE is introduced to represent Count value capture events. Cc: Julien Panis Link: https://lore.kernel.org/r/c239572ab4208d0d6728136e82a88ad464369a7a.1664204990.git.william.gray@linaro.org/ Signed-off-by: William Breathitt Gray Link: https://lore.kernel.org/r/3cebaa0b807a225eb277d771504fe6dba7269ffd.1664318353.git.william.gray@linaro.org Signed-off-by: Greg Kroah-Hartman

counter: Introduce the Signal polarity component

2022-09-30T12:32:35Z

The Signal polarity component represents the active level of a respective Signal. There are two possible states: positive (rising edge) and negative (falling edge); enum counter_signal_polarity represents these states. A convenience macro COUNTER_COMP_POLARITY() is provided for driver authors to declare a Signal polarity component. Cc: Julien Panis Link: https://lore.kernel.org/r/8f47d6e1db71a11bb1e2666f8e2a6e9d256d4131.1664204990.git.william.gray@linaro.org/ Signed-off-by: William Breathitt Gray Link: https://lore.kernel.org/r/b6e53438badcb6318997d13dd2fc052f97d808ac.1664318353.git.william.gray@linaro.org Signed-off-by: Greg Kroah-Hartman

counter: Implement events_queue_size sysfs attribute

2021-10-17T09:55:01Z

The events_queue_size sysfs attribute provides a way for users to dynamically configure the Counter events queue size for the Counter character device interface. The size is in number of struct counter_event data structures. The number of elements will be rounded-up to a power of 2 due to a requirement of the kfifo_alloc function called during reallocation of the queue. Cc: Oleksij Rempel Signed-off-by: William Breathitt Gray Link: https://lore.kernel.org/r/c914b2db2ea0a2637633bcc3e86ded3c94783f2e.1632884256.git.vilhelm.gray@gmail.com Signed-off-by: Jonathan Cameron

counter: Implement *_component_id sysfs attributes

2021-10-17T09:54:48Z

The Generic Counter chrdev interface expects users to supply component IDs in order to select extensions for requests. In order for users to know what component ID belongs to which extension this information must be exposed. The *_component_id attribute provides a way for users to discover what component ID belongs to which respective extension. Cc: David Lechner Cc: Gwendal Grignou Cc: Dan Carpenter Signed-off-by: William Breathitt Gray Link: https://lore.kernel.org/r/8961a11edbb882fc689e468194f5be75f572443e.1632884256.git.vilhelm.gray@gmail.com Signed-off-by: Jonathan Cameron