Re: [PATCH V2 2/3] arm64: dts: qcom: sc7180: Add sleep pin ctrl for BT uart

From: Akash Asthana
Date: Tue Jul 28 2020 - 01:38:53 EST



On 7/24/2020 9:28 AM, satya priya wrote:
Add sleep pin ctrl for BT uart, and also change the bias
configuration to match Bluetooth module.


Reviewed-by: Akash Asthana <akashast@xxxxxxxxxxxxxx>

Signed-off-by: satya priya <skakit@xxxxxxxxxxxxxx>
---
Changes in V2:
- This patch adds sleep state for BT UART. Newly added in V2.

arch/arm64/boot/dts/qcom/sc7180-idp.dts | 42 ++++++++++++++++++++++++++++-----
1 file changed, 36 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/sc7180-idp.dts b/arch/arm64/boot/dts/qcom/sc7180-idp.dts
index 26cc491..bc919f2 100644
--- a/arch/arm64/boot/dts/qcom/sc7180-idp.dts
+++ b/arch/arm64/boot/dts/qcom/sc7180-idp.dts
@@ -469,20 +469,50 @@
&qup_uart3_default {
pinconf-cts {
- /*
- * Configure a pull-down on 38 (CTS) to match the pull of
- * the Bluetooth module.
- */
+ /* Configure no pull on 38 (CTS) to match Bluetooth module */
pins = "gpio38";
+ bias-disable;
+ };
+
+ pinconf-rts {
+ /* We'll drive 39 (RTS), so configure pull-down */
+ pins = "gpio39";
+ drive-strength = <2>;
bias-pull-down;
+ };
+
+ pinconf-tx {
+ /* We'll drive 40 (TX), so no pull */
+ pins = "gpio40";
+ drive-strength = <2>;
+ bias-disable;
output-high;
};
+ pinconf-rx {
+ /*
+ * Configure a pull-up on 41 (RX). This is needed to avoid
+ * garbage data when the TX pin of the Bluetooth module is
+ * in tri-state (module powered off or not driving the
+ * signal yet).
+ */
+ pins = "gpio41";
+ bias-pull-up;
+ };
+};
+
+&qup_uart3_sleep {
+ pinconf-cts {
+ /* Configure no-pull on 38 (CTS) to match Bluetooth module */
+ pins = "gpio38";
+ bias-disable;
+ };
+
pinconf-rts {
- /* We'll drive 39 (RTS), so no pull */
+ /* We'll drive 39 (RTS), so configure pull-down */
pins = "gpio39";
drive-strength = <2>;
- bias-disable;
+ bias-pull-down;
};
pinconf-tx {

--
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