diff options
Diffstat (limited to 'Documentation/ABI')
| -rw-r--r-- | Documentation/ABI/obsolete/sysfs-gpio (renamed from Documentation/ABI/testing/sysfs-gpio) | 4 | ||||
| -rw-r--r-- | Documentation/ABI/testing/gpio-cdev | 26 |
2 files changed, 29 insertions, 1 deletions
diff --git a/Documentation/ABI/testing/sysfs-gpio b/Documentation/ABI/obsolete/sysfs-gpio index 55ffa2df1c10..867c1fab20e2 100644 --- a/Documentation/ABI/testing/sysfs-gpio +++ b/Documentation/ABI/obsolete/sysfs-gpio @@ -1,7 +1,7 @@ What: /sys/class/gpio/ Date: July 2008 KernelVersion: 2.6.27 -Contact: David Brownell <dbrownell@users.sourceforge.net> +Contact: Linus Walleij <linusw@kernel.org> Description: As a Kconfig option, individual GPIO signals may be accessed from @@ -26,3 +26,5 @@ Description: /label ... (r/o) descriptive, not necessarily unique /ngpio ... (r/o) number of GPIOs; numbered N to N + (ngpio - 1) + This ABI is deprecated and will be removed after 2020. It is + replaced with the GPIO character device. diff --git a/Documentation/ABI/testing/gpio-cdev b/Documentation/ABI/testing/gpio-cdev new file mode 100644 index 000000000000..7b265fbb47e3 --- /dev/null +++ b/Documentation/ABI/testing/gpio-cdev @@ -0,0 +1,26 @@ +What: /dev/gpiochip[0-9]+ +Date: November 2015 +KernelVersion: 4.4 +Contact: linux-gpio@vger.kernel.org +Description: + The character device files /dev/gpiochip* are the interface + between GPIO chips and userspace. + + The ioctl(2)-based ABI is defined and documented in + [include/uapi]<linux/gpio.h>. + + The following file operations are supported: + + open(2) + Currently the only useful flags are O_RDWR. + + ioctl(2) + Initiate various actions. + See the inline documentation in [include/uapi]<linux/gpio.h> + for descriptions of all ioctls. + + close(2) + Stops and free up the I/O contexts that was associated + with the file descriptor. + +Users: TBD |