Changes in v14: - Initialize counter_fops owner to THIS_MODULE - Implement ops_exist_lock to prevent counter->ops use during removal - Set counter->ops to NULL on counter_unregister to indicate removal; chrdev callbacks return -ENODEV if driver is removed - Refactor counter_fops read, poll, ioctl, and release callbacks to utilize ops_exist_lock where needed and to check counter->ops - Wake up sleeping chrdev read() on counter_unregister - Move chrdev_lock introduce to the "counter: Add character device interface" patch; this is a more appropriate place to introduce this lock because the chrdev code is intended from the get-go to only allow for a single open() at a time For convenience, this patchset is also available on my personal git repo: https://gitlab.com/vilhelmgray/iio/-/tree/counter_chrdev_v14 The patches preceding "counter: Internalize sysfs interface code" are primarily cleanup and fixes that can be picked up and applied now to the IIO tree if so desired. The "counter: Internalize sysfs interface code" patch as well may be considered for pickup because it is relatively safe and makes no changes to the userspace interface. To summarize the main points of this patchset: 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 (17): counter: 104-quad-8: Return error when invalid mode during ceiling_write counter: Return error code on invalid modes counter: Standardize to ERANGE for limit exceeded errors counter: Rename counter_signal_value to counter_signal_level counter: Rename counter_count_function to counter_function counter: Internalize sysfs interface code counter: Update counter.h comments to reflect sysfs internalization docs: counter: Update to reflect sysfs internalization counter: Move counter enums to uapi header counter: Add character device interface docs: counter: Document character device interface tools/counter: Create Counter tools counter: Implement signalZ_action_component_id sysfs attribute counter: Implement *_component_id sysfs attributes counter: Implement events_queue_size sysfs attribute counter: 104-quad-8: Replace mutex with spinlock counter: 104-quad-8: Add IRQ support for the ACCES 104-QUAD-8 Documentation/ABI/testing/sysfs-bus-counter | 38 +- Documentation/driver-api/generic-counter.rst | 358 +++- .../userspace-api/ioctl/ioctl-number.rst | 1 + MAINTAINERS | 3 +- drivers/counter/104-quad-8.c | 728 ++++---- drivers/counter/Kconfig | 6 +- drivers/counter/Makefile | 1 + drivers/counter/counter-chrdev.c | 553 ++++++ drivers/counter/counter-chrdev.h | 14 + drivers/counter/counter-core.c | 192 +++ drivers/counter/counter-sysfs.c | 962 +++++++++++ drivers/counter/counter-sysfs.h | 13 + drivers/counter/counter.c | 1496 ----------------- drivers/counter/ftm-quaddec.c | 59 +- drivers/counter/intel-qep.c | 150 +- drivers/counter/interrupt-cnt.c | 73 +- drivers/counter/microchip-tcb-capture.c | 103 +- drivers/counter/stm32-lptimer-cnt.c | 211 ++- drivers/counter/stm32-timer-cnt.c | 147 +- drivers/counter/ti-eqep.c | 205 ++- include/linux/counter.h | 719 ++++---- include/linux/counter_enum.h | 45 - include/uapi/linux/counter.h | 154 ++ tools/Makefile | 13 +- tools/counter/Build | 1 + tools/counter/Makefile | 53 + tools/counter/counter_example.c | 93 + 27 files changed, 3623 insertions(+), 2768 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 create mode 100644 tools/counter/Build create mode 100644 tools/counter/Makefile create mode 100644 tools/counter/counter_example.c -- 2.32.0
