[PATCH AUTOSEL 5.18 26/49] arm64: dts: qcom: sc7280-qcard: Configure CTS pin to bias-bus-hold for bluetooth

From: Sasha Levin
Date: Wed Jun 01 2022 - 09:54:47 EST


From: Vijaya Krishna Nivarthi <quic_vnivarth@xxxxxxxxxxx>

[ Upstream commit 3d0e375bae55c2dfa6dd0762f45ad71f0b192f71 ]

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@xxxxxxxxxxx>
Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Link: https://lore.kernel.org/r/1650556567-4995-3-git-send-email-quic_vnivarth@xxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/arm64/boot/dts/qcom/sc7280-qcard.dtsi | 19 ++++++++++++++-----
1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/sc7280-qcard.dtsi b/arch/arm64/boot/dts/qcom/sc7280-qcard.dtsi
index b833ba1e8f4a..98b5cd70bca5 100644
--- a/arch/arm64/boot/dts/qcom/sc7280-qcard.dtsi
+++ b/arch/arm64/boot/dts/qcom/sc7280-qcard.dtsi
@@ -398,8 +398,14 @@ &qup_i2c13_data_clk {

/* For mos_bt_uart */
&qup_uart7_cts {
- /* Configure a pull-down on CTS to match the pull of the Bluetooth module. */
- bias-pull-down;
+ /*
+ * 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-bus-hold;
};

/* For mos_bt_uart */
@@ -490,10 +496,13 @@ qup_uart7_sleep_cts: qup-uart7-sleep-cts {
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;
};

/* For mos_bt_uart */
--
2.35.1