WORKAROUND: arm64: dts: qcom: purwa-iot-evk: support Bluetooth over both USB and UART#1078
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…oth USB and UART On Purwa boards, a single M.2 slot may host either a UART-based or a USB-based Bluetooth device. As a result, the UART controller node is always present in DT, while the USB path is hot-pluggable. When Bluetooth operates over USB, the presence of the UART DT node still causes the hci_qca UART driver to probe. During probe or power sequencing, the driver may deassert BT_EN, cutting power to the shared Bluetooth device and disconnecting the USB interface. Model BT_EN as an always-on fixed regulator so it cannot be toggled by the UART probe. This prevents the UART driver from interfering with Bluetooth operation when the device is connected over USB. Workaround will be reverted once the M.2 solutionis available upstream. Signed-off-by: Wei Deng <wei.deng@oss.qualcomm.com>
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WORKAROUND: arm64: dts: qcom: purwa-iot-evk: support Bluetooth over both USB and UART
On Purwa boards, a single M.2 slot may host either a UART-based or a USB-based Bluetooth device. As a result, the UART controller node is always present in DT, while the USB path is hot-pluggable.
When Bluetooth operates over USB, the presence of the UART DT node still causes the hci_qca UART driver to probe. During probe or power sequencing, the driver may deassert BT_EN, cutting power to the shared Bluetooth device and disconnecting the USB interface.
Model BT_EN as an always-on fixed regulator so it cannot be toggled by the UART probe. This prevents the UART driver from interfering with Bluetooth operation when the device is connected over USB.
Workaround will be reverted once the M.2 solutionis available upstream.
CRs-Fixed: 4514156