w1/slaves/w1_ds28e17.rst

7   * Maxim DS28E17 1-Wire-to-I2C Master Bridge
19 -----------
20 The DS28E17 is a Onewire slave device which acts as an I2C bus master.
23 come and go as the DS28E17 devices come and go. I2C slave devices connected to
24 a DS28E17 can be accessed by the kernel or userspace tools as if they were
28 An udev rule like the following::
30   SUBSYSTEM=="i2c-dev", KERNEL=="i2c-[0-9]*", ATTRS{name}=="w1-19-*", \
31           SYMLINK+="i2c-$attr{name}"
33 may be used to create stable /dev/i2c- entries based on the unique id of the
40 	This sets up the default I2C speed a DS28E17 get configured for as soon
41 	it is connected. The power-on default	of the DS28E17 is 400kBaud, but
42 	chips may come and go on the Onewire bus without being de-powered and
43 	as soon the "w1_ds28e17" driver notices a freshly connected, or
44 	reconnected DS28E17 device on the Onewire bus, it will re-apply this
48 	alone the current DS28E17 setting on detect. The default value is 100.
51 	This sets up the default stretch value used for freshly connected
52 	DS28E17 devices. It is a multiplier used on the calculation of the busy
54 	which make heavy use of the I2C clock stretching feature and thus, the
55 	needed timeout cannot be pre-calculated correctly. As the w1_ds28e17
56 	driver checks the DS28E17's busy flag in a loop after the precalculated
60 	19-00000002dbd8: busy timeout" in the kernel log.
62 	Valid values are 1 to 9. The default is 1.
65 The driver creates sysfs files /sys/bus/w1/devices/19-<id>/speed and
66 /sys/bus/w1/devices/19-<id>/stretch for each device, preloaded with the default
67 settings from the driver parameters. They may be changed anytime. In addition a
68 directory /sys/bus/w1/devices/19-<id>/i2c-<nnn> for the I2C bus master sysfs