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authorLinus Torvalds <torvalds@linux-foundation.org>2013-02-21 13:57:13 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2013-02-21 13:57:13 -0800
commit7ed214ac2095f561a94335ca672b6c42a1ea40ff (patch)
treeda41901bff1d0d8d61170bf362384fdc61deb3ab /Documentation
parent21eaab6d19ed43e82ed39c8deb7f192134fb4a0e (diff)
parent29e5507ae4ab34397f538f06b7070c81a4e4a2bf (diff)
Merge tag 'char-misc-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver patches from Greg Kroah-Hartman: "Here's the big char/misc driver patches for 3.9-rc1. Nothing major here, just lots of different driver updates (mei, hyperv, ipack, extcon, vmci, etc.). All of these have been in the linux-next tree for a while." * tag 'char-misc-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (209 commits) w1: w1_therm: Add force-pullup option for "broken" sensors w1: ds2482: Added 1-Wire pull-up support to the driver vme: add missing put_device() after device_register() fails extcon: max8997: Use workqueue to check cable state after completing boot of platform extcon: max8997: Set default UART/USB path on probe extcon: max8997: Consolidate duplicate code for checking ADC/CHG cable type extcon: max8997: Set default of ADC debounce time during initialization extcon: max8997: Remove duplicate code related to set H/W line path extcon: max8997: Move defined constant to header file extcon: max77693: Make max77693_extcon_cable static extcon: max8997: Remove unreachable code extcon: max8997: Make max8997_extcon_cable static extcon: max77693: Remove unnecessary goto statement to improve readability extcon: max77693: Convert to devm_input_allocate_device() extcon: gpio: Rename filename of extcon-gpio.c according to kernel naming style CREDITS: update email and address of Harald Hoyer extcon: arizona: Use MICDET for final microphone identification extcon: arizona: Always take the first HPDET reading as the final one extcon: arizona: Clear _trig_sts bits after jack detection extcon: arizona: Don't HPDET magic when headphones are enabled ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/DocBook/uio-howto.tmpl2
-rw-r--r--Documentation/w1/slaves/w1_therm13
2 files changed, 11 insertions, 4 deletions
diff --git a/Documentation/DocBook/uio-howto.tmpl b/Documentation/DocBook/uio-howto.tmpl
index ddb05e98af0..95618159e29 100644
--- a/Documentation/DocBook/uio-howto.tmpl
+++ b/Documentation/DocBook/uio-howto.tmpl
@@ -984,7 +984,7 @@ int main()
return errno;
}
configfd = open(&quot;/sys/class/uio/uio0/device/config&quot;, O_RDWR);
- if (uiofd &lt; 0) {
+ if (configfd &lt; 0) {
perror(&quot;config open:&quot;);
return errno;
}
diff --git a/Documentation/w1/slaves/w1_therm b/Documentation/w1/slaves/w1_therm
index 874a8ca93fe..cc62a95e477 100644
--- a/Documentation/w1/slaves/w1_therm
+++ b/Documentation/w1/slaves/w1_therm
@@ -34,9 +34,16 @@ currently supported. The driver also doesn't support reduced
precision (which would also reduce the conversion time).
The module parameter strong_pullup can be set to 0 to disable the
-strong pullup or 1 to enable. If enabled the 5V strong pullup will be
-enabled when the conversion is taking place provided the master driver
-must support the strong pullup (or it falls back to a pullup
+strong pullup, 1 to enable autodetection or 2 to force strong pullup.
+In case of autodetection, the driver will use the "READ POWER SUPPLY"
+command to check if there are pariste powered devices on the bus.
+If so, it will activate the master's strong pullup.
+In case the detection of parasite devices using this command fails
+(seems to be the case with some DS18S20) the strong pullup can
+be force-enabled.
+If the strong pullup is enabled, the master's strong pullup will be
+driven when the conversion is taking place, provided the master driver
+does support the strong pullup (or it falls back to a pullup
resistor). The DS18b20 temperature sensor specification lists a
maximum current draw of 1.5mA and that a 5k pullup resistor is not
sufficient. The strong pullup is designed to provide the additional