diff options
Diffstat (limited to 'Documentation/ABI/testing')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-firmware-sgi_uv | 27 | ||||
| -rw-r--r-- | Documentation/ABI/testing/sysfs-gpio | 26 |
2 files changed, 53 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-firmware-sgi_uv b/Documentation/ABI/testing/sysfs-firmware-sgi_uv new file mode 100644 index 00000000000..4573fd4b787 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-firmware-sgi_uv @@ -0,0 +1,27 @@ +What: /sys/firmware/sgi_uv/ +Date: August 2008 +Contact: Russ Anderson <rja@sgi.com> +Description: + The /sys/firmware/sgi_uv directory contains information + about the SGI UV platform. + + Under that directory are a number of files: + + partition_id + coherence_id + + The partition_id entry contains the partition id. + SGI UV systems can be partitioned into multiple physical + machines, which each partition running a unique copy + of the operating system. Each partition will have a unique + partition id. To display the partition id, use the command: + + cat /sys/firmware/sgi_uv/partition_id + + The coherence_id entry contains the coherence id. + A partitioned SGI UV system can have one or more coherence + domain. The coherence id indicates which coherence domain + this partition is in. To display the coherence id, use the + command: + + cat /sys/firmware/sgi_uv/coherence_id diff --git a/Documentation/ABI/testing/sysfs-gpio b/Documentation/ABI/testing/sysfs-gpio new file mode 100644 index 00000000000..8aab8092ad3 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-gpio @@ -0,0 +1,26 @@ +What: /sys/class/gpio/ +Date: July 2008 +KernelVersion: 2.6.27 +Contact: David Brownell <dbrownell@users.sourceforge.net> +Description: + + As a Kconfig option, individual GPIO signals may be accessed from + userspace. GPIOs are only made available to userspace by an explicit + "export" operation. If a given GPIO is not claimed for use by + kernel code, it may be exported by userspace (and unexported later). + Kernel code may export it for complete or partial access. + + GPIOs are identified as they are inside the kernel, using integers in + the range 0..INT_MAX. See Documentation/gpio.txt for more information. + + /sys/class/gpio + /export ... asks the kernel to export a GPIO to userspace + /unexport ... to return a GPIO to the kernel + /gpioN ... for each exported GPIO #N + /value ... always readable, writes fail for input GPIOs + /direction ... r/w as: in, out (default low); write: high, low + /gpiochipN ... for each gpiochip; #N is its first GPIO + /base ... (r/o) same as N + /label ... (r/o) descriptive, not necessarily unique + /ngpio ... (r/o) number of GPIOs; numbered N to N + (ngpio - 1) + |