linux/drivers/w1/masters
Mariusz Bialonczyk f704938c0e w1: enable active pullup for DS2482 by default
This commit enables the active pullup (APU bit) by default for
the DS2482 1-Wire master.

>From the DS2482 datasheet:
"The APU bit controls whether an active pullup (controlled slew-rate
transistor) or a passive pullup (Rwpu resistor) will be used to drive
a 1-Wire line from low to high. When APU = 0, active pullup is disabled
(resistor mode). Active Pullup should always be selected unless there is
only a single slave on the 1-Wire line."

According to the module author, Ben Gardner:
"It doesn't look like active pullup would cause any hurt if there
is only a single slave."
And my tests with multiple and single slaves on 1-Wire bus
confirms that.

This active pullup can be manually disabled using the introduced
module parameter:
  active_pullup = 0

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-01 14:04:19 -07:00
..
ds1wm.c
ds2482.c w1: enable active pullup for DS2482 by default 2016-05-01 14:04:19 -07:00
ds2490.c
Kconfig
Makefile
matrox_w1.c
mxc_w1.c
omap_hdq.c
w1-gpio.c