lkml.org 
[lkml]   [2022]   [Apr]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[V6 1/2] arm64: dts: qcom: sc7280-idp: Configure CTS pin to bias-bus-hold for bluetooth
Date
WLAN rail was leaking power during RBSC/sleep even after turning BT off.
Change active and sleep pinctrl configurations to handle same.

Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
---
v6: add code comments about how bias-bus-hold could save power
v5: modify subject to include bluetooth
v4: modify subject of patch to indicate file it is applying to
v3: apply same change to active state and other sc7280*.dts* as well
v2: used bias-bus-hold as per review comments
v1: intial patch used bias-disable for sleep pinctrl in sc7280-idp only
---
arch/arm64/boot/dts/qcom/sc7280-idp.dtsi | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/sc7280-idp.dtsi b/arch/arm64/boot/dts/qcom/sc7280-idp.dtsi
index 015a347..6c2aab6 100644
--- a/arch/arm64/boot/dts/qcom/sc7280-idp.dtsi
+++ b/arch/arm64/boot/dts/qcom/sc7280-idp.dtsi
@@ -400,10 +400,13 @@

&qup_uart7_cts {
/*
- * Configure a pull-down on CTS to match the pull of
- * the Bluetooth module.
+ * Configure a bias-bus-hold on CTS to lower power
+ * usage when Bluetooth is turned off. Bus hold will
+ * maintain a low power state regardless of whether
+ * the Bluetooth module drives the pin in either
+ * direction or leaves the pin fully unpowered.
*/
- bias-pull-down;
+ bias-bus-hold;
};

&qup_uart7_rts {
@@ -495,10 +498,13 @@
pins = "gpio28";
function = "gpio";
/*
- * Configure a pull-down on CTS to match the pull of
- * the Bluetooth module.
+ * Configure a bias-bus-hold on CTS to lower power
+ * usage when Bluetooth is turned off. Bus hold will
+ * maintain a low power state regardless of whether
+ * the Bluetooth module drives the pin in either
+ * direction or leaves the pin fully unpowered.
*/
- bias-pull-down;
+ bias-bus-hold;
};

qup_uart7_sleep_rts: qup-uart7-sleep-rts {
--
Qualcomm INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by the Linux Foundation.
\
 
 \ /
  Last update: 2022-04-21 17:57    [W:0.038 / U:0.124 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site