diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/stable/sysfs-bus-w1 | 11 | ||||
| -rw-r--r-- | Documentation/w1/w1.generic | 30 |
2 files changed, 30 insertions, 11 deletions
diff --git a/Documentation/ABI/stable/sysfs-bus-w1 b/Documentation/ABI/stable/sysfs-bus-w1 new file mode 100644 index 000000000000..140d85b4ae92 --- /dev/null +++ b/Documentation/ABI/stable/sysfs-bus-w1 @@ -0,0 +1,11 @@ +What: /sys/bus/w1/devices/.../w1_master_timeout_us +Date: April 2015 +Contact: Dmitry Khromov <dk@icelogic.net> +Description: Bus scanning interval, microseconds component. + Some of 1-Wire devices commonly associated with physical access + control systems are attached/generate presence for as short as + 100 ms - hence the tens-to-hundreds milliseconds scan intervals + are required. + see Documentation/w1/w1.generic for detailed information. +Users: any user space application which wants to know bus scanning + interval diff --git a/Documentation/w1/w1.generic b/Documentation/w1/w1.generic index b2033c64c7da..b3ffaf8cfab2 100644 --- a/Documentation/w1/w1.generic +++ b/Documentation/w1/w1.generic @@ -76,21 +76,24 @@ See struct w1_bus_master definition in w1.h for details. w1 master sysfs interface ------------------------------------------------------------------ -<xx-xxxxxxxxxxxxx> - a directory for a found device. The format is family-serial +<xx-xxxxxxxxxxxxx> - A directory for a found device. The format is family-serial bus - (standard) symlink to the w1 bus driver - (standard) symlink to the w1 driver -w1_master_add - Manually register a slave device -w1_master_attempts - the number of times a search was attempted +w1_master_add - (rw) manually register a slave device +w1_master_attempts - (ro) the number of times a search was attempted w1_master_max_slave_count - - maximum number of slaves to search for at a time -w1_master_name - the name of the device (w1_bus_masterX) -w1_master_pullup - 5V strong pullup 0 enabled, 1 disabled -w1_master_remove - Manually remove a slave device -w1_master_search - the number of searches left to do, -1=continual (default) + - (rw) maximum number of slaves to search for at a time +w1_master_name - (ro) the name of the device (w1_bus_masterX) +w1_master_pullup - (rw) 5V strong pullup 0 enabled, 1 disabled +w1_master_remove - (rw) manually remove a slave device +w1_master_search - (rw) the number of searches left to do, + -1=continual (default) w1_master_slave_count - - the number of slaves found -w1_master_slaves - the names of the slaves, one per line -w1_master_timeout - the delay in seconds between searches + - (ro) the number of slaves found +w1_master_slaves - (ro) the names of the slaves, one per line +w1_master_timeout - (ro) the delay in seconds between searches +w1_master_timeout_us + - (ro) the delay in microseconds beetwen searches If you have a w1 bus that never changes (you don't add or remove devices), you can set the module parameter search_count to a small positive number @@ -101,6 +104,11 @@ generally only make sense when searching is disabled, as a search will redetect manually removed devices that are present and timeout manually added devices that aren't on the bus. +Bus searches occur at an interval, specified as a summ of timeout and +timeout_us module parameters (either of which may be 0) for as long as +w1_master_search remains greater than 0 or is -1. Each search attempt +decrements w1_master_search by 1 (down to 0) and increments +w1_master_attempts by 1. w1 slave sysfs interface ------------------------------------------------------------------ |