[V6 0/2] arm64: dts: qcom: Configure CTS pin to bias-bus-hold for bluetooth

[V6 0/2] arm64: dts: qcom: Configure CTS pin to bias-bus-hold for bluetooth

[Vijaya Krishna Nivarthi]

WLAN rail was leaking power during RBSC/sleep even after turning BT off.
Change pinctrl configuration to handle same.

Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com>
---
v6: add code comments about how bias-bus-hold could save power
v5: modify subject to include bluetooth
v4: modify subject of each patch to indicate what 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
---

Vijaya Krishna Nivarthi (2):
  arm64: dts: qcom: sc7280-idp: Configure CTS pin to bias-bus-hold for
    bluetooth
  arm64: dts: qcom: sc7280-qcard: Configure CTS pin to bias-bus-hold for
    bluetooth

 arch/arm64/boot/dts/qcom/sc7280-idp.dtsi   | 18 ++++++++++++------
 arch/arm64/boot/dts/qcom/sc7280-qcard.dtsi | 19 ++++++++++++++-----
 2 files changed, 26 insertions(+), 11 deletions(-)

-- 
Qualcomm INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by the Linux Foundation.

[V6 1/2] arm64: dts: qcom: sc7280-idp: Configure CTS pin to bias-bus-hold for bluetooth

[Vijaya Krishna Nivarthi]

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.

[V6 2/2] arm64: dts: qcom: sc7280-qcard: Configure CTS pin to bias-bus-hold for bluetooth

[Vijaya Krishna Nivarthi]

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-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 b833ba1..98b5cd70 100644
--- a/arch/arm64/boot/dts/qcom/sc7280-qcard.dtsi
+++ b/arch/arm64/boot/dts/qcom/sc7280-qcard.dtsi
@@ -398,8 +398,14 @@ mos_bt_uart: &uart7 {
 
 /* 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 @@ mos_bt_uart: &uart7 {
 		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 */
-- 
Qualcomm INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by the Linux Foundation.

Re: [V6 0/2] arm64: dts: qcom: Configure CTS pin to bias-bus-hold for bluetooth

[Doug Anderson]

Bjorn,

On Thu, Apr 21, 2022 at 8:56 AM Vijaya Krishna Nivarthi
<quic_vnivarth@quicinc.com> wrote:
>
> WLAN rail was leaking power during RBSC/sleep even after turning BT off.
> Change pinctrl configuration to handle same.
>
> Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com>
> ---
> v6: add code comments about how bias-bus-hold could save power
> v5: modify subject to include bluetooth
> v4: modify subject of each patch to indicate what 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
> ---
>
> Vijaya Krishna Nivarthi (2):
>   arm64: dts: qcom: sc7280-idp: Configure CTS pin to bias-bus-hold for
>     bluetooth
>   arm64: dts: qcom: sc7280-qcard: Configure CTS pin to bias-bus-hold for
>     bluetooth
>
>  arch/arm64/boot/dts/qcom/sc7280-idp.dtsi   | 18 ++++++++++++------
>  arch/arm64/boot/dts/qcom/sc7280-qcard.dtsi | 19 ++++++++++++++-----
>  2 files changed, 26 insertions(+), 11 deletions(-)

If the tree hasn't closed yet, I think these two patches are waiting
to land and ready to go.

Thanks!

-Doug

Re: [V6 0/2] arm64: dts: qcom: Configure CTS pin to bias-bus-hold for bluetooth

[Bjorn Andersson]

On Thu, 21 Apr 2022 21:26:05 +0530, Vijaya Krishna Nivarthi wrote:
> WLAN rail was leaking power during RBSC/sleep even after turning BT off.
> Change pinctrl configuration to handle same.
> 
> 

Applied, thanks!

[1/2] arm64: dts: qcom: sc7280-idp: Configure CTS pin to bias-bus-hold for bluetooth
      commit: 497b272759986af1aa5a25b5e903d082c67bd8f6
[2/2] arm64: dts: qcom: sc7280-qcard: Configure CTS pin to bias-bus-hold for bluetooth
      commit: 3d0e375bae55c2dfa6dd0762f45ad71f0b192f71

Best regards,
-- 
Bjorn Andersson <bjorn.andersson@linaro.org>