[PATCH v3] ARM: dts: samsung: exynos4210-*: Fix Bluetooth nodes

From: Paul Cercueil

Date: Fri Sep 18 2026 - 17:38:03 EST


The BCM4330 Bluetooth chip is capable of doing 4 Mbps over UART. The
Exynos 4210 however, can only do a maximum of 3 Mbps. Add this
information to the Bluetooth nodes using the 'max-speed' property.

This fixes extremely choppy audio when connected to external Bluetooth
speakers.

The BCM4330 is connected using CTS/RTS too, so add the 'uart-has-rtscts'
property. The driver does not seem to check for it but that still should
be there.

Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
---

Apologies if you receive this email for the second time. I messed up
on the previous one and forgot to Cc the lists. Since nothing
changed, this is still v3.

Cheers,
-Paul

Changes:

V1 was: "ARM: dts: samsung: exynos4210-i9100: Fix Bluetooth node"

-v2: Drop max-speed property. It's only supposed to be used in some
cases, which don't apply here. As this was the "fix" for getting
Bluetooth to work on my device, which will be applied to the
driver instead, the Fixes: tag was removed.

-v3: Re-introduce max-speed property :)
Turns out the use case does indeed apply here.
Also update the other Exynos4210 based boards.

arch/arm/boot/dts/samsung/exynos4210-i9100.dts | 4 ++++
arch/arm/boot/dts/samsung/exynos4210-trats.dts | 5 +++++
arch/arm/boot/dts/samsung/exynos4210-universal_c210.dts | 5 +++++
3 files changed, 14 insertions(+)

diff --git a/arch/arm/boot/dts/samsung/exynos4210-i9100.dts b/arch/arm/boot/dts/samsung/exynos4210-i9100.dts
index 7da64500246c..ff369eac344f 100644
--- a/arch/arm/boot/dts/samsung/exynos4210-i9100.dts
+++ b/arch/arm/boot/dts/samsung/exynos4210-i9100.dts
@@ -868,9 +868,13 @@ &serial_0 {
pinctrl-names = "default";
pinctrl-0 = <&bt_en>, <&bt_res>, <&uart0_data>, <&uart0_fctl>;

+ uart-has-rtscts;
+
bluetooth {
compatible = "brcm,bcm4330-bt";

+ max-speed = <3000000>;
+
shutdown-gpios = <&gpl0 4 GPIO_ACTIVE_HIGH>;
reset-gpios = <&gpl1 0 GPIO_ACTIVE_LOW>;
device-wakeup-gpios = <&gpx3 1 GPIO_ACTIVE_HIGH>;
diff --git a/arch/arm/boot/dts/samsung/exynos4210-trats.dts b/arch/arm/boot/dts/samsung/exynos4210-trats.dts
index eb286e25835e..c517f6d1d7c2 100644
--- a/arch/arm/boot/dts/samsung/exynos4210-trats.dts
+++ b/arch/arm/boot/dts/samsung/exynos4210-trats.dts
@@ -537,8 +537,13 @@ &serial_0 {
pinctrl-0 = <&uart0_data &uart0_fctl>;
pinctrl-names = "default";

+ uart-has-rtscts;
+
bluetooth {
compatible = "brcm,bcm4330-bt";
+
+ max-speed = <3000000>;
+
pinctrl-0 = <&bt_shutdown &bt_device_wakeup &bt_host_wakeup>;
pinctrl-names = "default";
shutdown-gpios = <&gpl1 0 GPIO_ACTIVE_HIGH>;
diff --git a/arch/arm/boot/dts/samsung/exynos4210-universal_c210.dts b/arch/arm/boot/dts/samsung/exynos4210-universal_c210.dts
index 71df3843d8ba..9b345e16c44f 100644
--- a/arch/arm/boot/dts/samsung/exynos4210-universal_c210.dts
+++ b/arch/arm/boot/dts/samsung/exynos4210-universal_c210.dts
@@ -630,8 +630,13 @@ &serial_0 {
pinctrl-0 = <&uart0_data &uart0_fctl>;
pinctrl-names = "default";

+ uart-has-rtscts;
+
bluetooth {
compatible = "brcm,bcm4330-bt";
+
+ max-speed = <3000000>;
+
pinctrl-0 = <&bt_shutdown &bt_device_wakeup &bt_host_wakeup>;
pinctrl-names = "default";
shutdown-gpios = <&gpe1 4 GPIO_ACTIVE_HIGH>;
--
2.53.0