From: Peter Rosin <peda@axentia.se>
To: linux-kernel@vger.kernel.org
Cc: Peter Rosin <peda@axentia.se>, Sebastian Reichel <sre@kernel.org>,
        Rob Herring <robh+dt@kernel.org>, Mark Rutland <mark.rutland@arm.com>,
        Jon Hunter <jonathanh@nvidia.com>,
        Stephen Warren <swarren@wwwdotorg.org>, linux-pm@vger.kernel.org,
        devicetree@vger.kernel.org
Subject: [PATCH v4] dt-bindings: power: supply: bq24735: reverse the polarity of ac-detect
Date: Fri, 16 Dec 2016 10:44:00 +0100
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The ACOK pin on the bq24735 is active-high, of course meaning that when
AC is OK the pin is high. However, all Tegra dts files have incorrectly
specified active-high even though the signal is inverted on the Tegra
boards. This has worked since the Linux driver has also inverted the
meaning of the GPIO. Fix this situation by simply specifying in the
bindings what everybody else agrees on; that the ti,ac-detect-gpios is
active on AC adapter absence.

Signed-off-by: Peter Rosin <peda@axentia.se>
---
 Documentation/devicetree/bindings/power/supply/ti,bq24735.txt | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

Hi!

v3 -> v4 changes:
- improve the bindings text in the spirit of remarks from Jon Hunter

(There were no v1 nor v2, I made a mistake and started from v3 this time.)

This patch is the result of this discussion:
http://marc.info/?t=148152531800002

I don't like how it changes the one thing that is seems correct, but
what to do?

Cheers,
peda

diff --git a/Documentation/devicetree/bindings/power/supply/ti,bq24735.txt b/Documentation/devicetree/bindings/power/supply/ti,bq24735.txt
index 3bf55757ceec..c95e16e2dc56 100644
--- a/Documentation/devicetree/bindings/power/supply/ti,bq24735.txt
+++ b/Documentation/devicetree/bindings/power/supply/ti,bq24735.txt
@@ -8,8 +8,10 @@ Optional properties :
  - interrupts : Specify the interrupt to be used to trigger when the AC
    adapter is either plugged in or removed.
  - ti,ac-detect-gpios : This GPIO is optionally used to read the AC adapter
-   presence. This is a Host GPIO that is configured as an input and
-   connected to the bq24735.
+   status. This is a Host GPIO that is configured as an input and connected
+   to the ACOK pin on the bq24735. Note: for backwards compatibility reasons,
+   the GPIO must be active on AC adapter absence despite ACOK being active
+   (high) on AC adapter presence.
  - ti,charge-current : Used to control and set the charging current. This value
    must be between 128mA and 8.128A with a 64mA step resolution. The POR value
    is 0x0000h. This number is in mA (e.g. 8192), see spec for more information
-- 
2.1.4