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Diffstat (limited to 'Documentation/w1/slaves/w1_ds28e17')
| -rw-r--r-- | Documentation/w1/slaves/w1_ds28e17 | 68 |
1 files changed, 0 insertions, 68 deletions
diff --git a/Documentation/w1/slaves/w1_ds28e17 b/Documentation/w1/slaves/w1_ds28e17 deleted file mode 100644 index 7fcfad5b4a37..000000000000 --- a/Documentation/w1/slaves/w1_ds28e17 +++ /dev/null @@ -1,68 +0,0 @@ -Kernel driver w1_ds28e17 -======================== - -Supported chips: - * Maxim DS28E17 1-Wire-to-I2C Master Bridge - -supported family codes: - W1_FAMILY_DS28E17 0x19 - -Author: Jan Kandziora <jjj@gmx.de> - - -Description ------------ -The DS28E17 is a Onewire slave device which acts as an I2C bus master. - -This driver creates a new I2C bus for any DS28E17 device detected. I2C buses -come and go as the DS28E17 devices come and go. I2C slave devices connected to -a DS28E17 can be accessed by the kernel or userspace tools as if they were -connected to a "native" I2C bus master. - - -An udev rule like the following -------------------------------------------------------------------------------- -SUBSYSTEM=="i2c-dev", KERNEL=="i2c-[0-9]*", ATTRS{name}=="w1-19-*", \ - SYMLINK+="i2c-$attr{name}" -------------------------------------------------------------------------------- -may be used to create stable /dev/i2c- entries based on the unique id of the -DS28E17 chip. - - -Driver parameters are: - -speed: - This sets up the default I2C speed a DS28E17 get configured for as soon - it is connected. The power-on default of the DS28E17 is 400kBaud, but - chips may come and go on the Onewire bus without being de-powered and - as soon the "w1_ds28e17" driver notices a freshly connected, or - reconnected DS28E17 device on the Onewire bus, it will re-apply this - setting. - - Valid values are 100, 400, 900 [kBaud]. Any other value means to leave - alone the current DS28E17 setting on detect. The default value is 100. - -stretch: - This sets up the default stretch value used for freshly connected - DS28E17 devices. It is a multiplier used on the calculation of the busy - wait time for an I2C transfer. This is to account for I2C slave devices - which make heavy use of the I2C clock stretching feature and thus, the - needed timeout cannot be pre-calculated correctly. As the w1_ds28e17 - driver checks the DS28E17's busy flag in a loop after the precalculated - wait time, it should be hardly needed to tweak this setting. - - Leave it at 1 unless you get ETIMEDOUT errors and a "w1_slave_driver - 19-00000002dbd8: busy timeout" in the kernel log. - - Valid values are 1 to 9. The default is 1. - - -The driver creates sysfs files /sys/bus/w1/devices/19-<id>/speed and -/sys/bus/w1/devices/19-<id>/stretch for each device, preloaded with the default -settings from the driver parameters. They may be changed anytime. In addition a -directory /sys/bus/w1/devices/19-<id>/i2c-<nnn> for the I2C bus master sysfs -structure is created. - - -See https://github.com/ianka/w1_ds28e17 for even more information. - |