Re: [PATCH v2] ARM: dts: exynos: Add bluetooth support to manta

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Missing `max-speed` property in the Bluetooth node significantly restricts UART bandwidth.
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commit 661518d39bb3c0a9a3884e1d914c3ff2bc70cf74
Author: Lukas Timmermann <linux@timmermann.space>

ARM: dts: exynos: Add bluetooth support to manta

This commit enables the bcm4330-bt device for manta boards on serial0.
It also adds the necessary pin definitions and interrupt handling for wakeup.

> diff --git a/arch/arm/boot/dts/samsung/exynos5250-manta.dts b/arch/arm/boot/dts/samsung/exynos5250-manta.dts
> index 24a27b342227b..76d3657eb22f0 100644
> --- a/arch/arm/boot/dts/samsung/exynos5250-manta.dts
> +++ b/arch/arm/boot/dts/samsung/exynos5250-manta.dts

[ ... ]

> @@ -536,7 +557,25 @@ &sd1_cmd {
>  
>  /* Bluetooth */
>  &serial_0 {
> -	status = "disabled";
> +	pinctrl-0 = <&uart0_data &uart0_fctl>;
> +	pinctrl-names = "default";
> +
> +	bluetooth {
> +		compatible = "brcm,bcm4330-bt";
> +
> +		pinctrl-0 = <&bt_reg_on &bt_wake &bt_host_wakeup>;

[Severity: Medium]
Should this node include a max-speed property to negotiate a high-speed
UART connection?

Without max-speed, the brcm,bcm4330-bt driver in drivers/bluetooth/hci_bcm.c
leaves the oper_speed at 0 and skips negotiating a higher baud rate. This
forces the UART to operate at its default 115200 bps. 

Operating at 115200 bps restricts the bandwidth to around 11.5 KB/s, which
can cause high-bandwidth Bluetooth profiles like A2DP to stutter or fail.
Other Exynos boards typically set max-speed (e.g., max-speed = <3000000>)
to prevent this bottleneck.

> +		pinctrl-names = "default";
> +
> +		shutdown-gpios = <&gph0 0 GPIO_ACTIVE_HIGH>;
> +		device-wakeup-gpios = <&gph1 3 GPIO_ACTIVE_HIGH>;

[ ... ]

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260614-manta-bluetooth-v2-1-52de06cabf9d@timmermann.space?part=1