Changes in v7: - Implemented u32 enums; enum types can now be used directly for callbacks and values - Fixed refcount underflow bug - Refactored all err check to check for err < 0; this should help prevent future oversights on valid positive return valids - Use mutex instead of raw_spin_lock in counter_chrdev_read(); kifo_to_user() can now safely sleep - Renamed COUNTER_COMPONENT_DUMMY to COUNTER_COMPONENT_NONE to make purpose more obvious - Introduced a watch_validate() callback - Consolidated the functionality to clear the watches to the counter_clear_watches() function - Reimplemented counter_push_event() as a void function; on error, errno is returned via struct counter_event so that it can be handled by userspace (because interrupt handlers can't do much for this) - Renamed the events_config() callback to events_configure(); "events_config" could be confused as a read callback when this is actually intended to configure the device for the requested events - Reimplemented 104-QUAD-8 driver to use events_configure() and watch_validate() callbacks; irq_trigger_enable sysfs attribute removed because events_configure() now serves this purpose The changes for this revision were much simpler compared to the previous revisions. I don't have any further questions for this patchset, so it's really just a search for possible bugs or regressions now. Please test and verify this patchset on your systems, and ACK appropriately. To summarize the main points: there are no changes to the existing Counter sysfs userspace interface; a Counter character device interface is introduced that allows Counter events and associated data to be read() by userspace; the events_configure() and watch_validate() driver callbacks are introduced to support Counter events; and IRQ support is added to the 104-QUAD-8 driver, serving as an example of how to support the new Counter events functionality. William Breathitt Gray (5): counter: Internalize sysfs interface code docs: counter: Update to reflect sysfs internalization counter: Add character device interface docs: counter: Document character device interface counter: 104-quad-8: Add IRQ support for the ACCES 104-QUAD-8 Documentation/ABI/testing/sysfs-bus-counter | 18 +- .../ABI/testing/sysfs-bus-counter-104-quad-8 | 25 + Documentation/driver-api/generic-counter.rst | 416 ++++- .../userspace-api/ioctl/ioctl-number.rst | 1 + MAINTAINERS | 2 +- drivers/counter/104-quad-8.c | 799 +++++---- drivers/counter/Kconfig | 6 +- drivers/counter/Makefile | 1 + drivers/counter/counter-chrdev.c | 490 ++++++ drivers/counter/counter-chrdev.h | 16 + drivers/counter/counter-core.c | 182 ++ drivers/counter/counter-sysfs.c | 868 ++++++++++ drivers/counter/counter-sysfs.h | 13 + drivers/counter/counter.c | 1496 ----------------- drivers/counter/ftm-quaddec.c | 61 +- drivers/counter/microchip-tcb-capture.c | 103 +- drivers/counter/stm32-lptimer-cnt.c | 181 +- drivers/counter/stm32-timer-cnt.c | 149 +- drivers/counter/ti-eqep.c | 224 +-- include/linux/counter.h | 716 ++++---- include/linux/counter_enum.h | 45 - include/uapi/linux/counter.h | 123 ++ 22 files changed, 3259 insertions(+), 2676 deletions(-) create mode 100644 drivers/counter/counter-chrdev.c create mode 100644 drivers/counter/counter-chrdev.h create mode 100644 drivers/counter/counter-core.c create mode 100644 drivers/counter/counter-sysfs.c create mode 100644 drivers/counter/counter-sysfs.h delete mode 100644 drivers/counter/counter.c delete mode 100644 include/linux/counter_enum.h create mode 100644 include/uapi/linux/counter.h -- 2.29.2