diff options
Diffstat (limited to 'drivers/staging/fieldbus/Documentation/ABI/fieldbus-dev-cdev')
| -rw-r--r-- | drivers/staging/fieldbus/Documentation/ABI/fieldbus-dev-cdev | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/drivers/staging/fieldbus/Documentation/ABI/fieldbus-dev-cdev b/drivers/staging/fieldbus/Documentation/ABI/fieldbus-dev-cdev new file mode 100644 index 000000000000..45f631ea32a6 --- /dev/null +++ b/drivers/staging/fieldbus/Documentation/ABI/fieldbus-dev-cdev @@ -0,0 +1,31 @@ +What: /dev/fieldbus_devX +Date: December 2018 +KernelVersion: 5.1 (staging) +Contact: Sven Van Asbroeck <TheSven73@gmail.com> +Description: + The cdev interface to drivers for Fieldbus Device Memory + (aka. Process Memory). + + The following file operations are supported: + + open(2) + Create an I/O context associated with the file descriptor. + + read(2) + Read from Process Memory's "read area". + Clears POLLERR | POLLPRI from the file descriptor. + + write(2) + Write to Process Memory's "write area". + + poll(2), select(2), epoll_wait(2) etc. + When a "Process Memory Read Area Changed" event occurs, + POLLERR | POLLPRI will be set on the file descriptor. + Note that POLLIN | POLLOUT events are always set, because the + process memory area is always readable and writable. + + close(2) + Free up the I/O context that was associated + with the file descriptor. + +Users: TBD |