Re: [PATCH v2] Bluetooth: btusb: fix bt fiwmare downloading failure issue for qca btsoc.

[Marcel Holtmann]

Hi Zijun,

> This is btsoc timing issue, after host start to downloading bt firmware,
> ep2 need time to switch from function acl to function dfu, so host add
> 20ms delay as workaround.
> 
> Signed-off-by: Tim Jiang <tjiang@xxxxxxxxxxxxxx>
> ---
> drivers/bluetooth/btusb.c | 1 +
> 1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
> index 5245714..b0743db 100644
> --- a/drivers/bluetooth/btusb.c
> +++ b/drivers/bluetooth/btusb.c
> @@ -4064,6 +4064,7 @@ static int btusb_setup_qca_download_fw(struct hci_dev *hdev,
> 
> 	sent += size;
> 	count -= size;

you need a comment here explain why this is needed.

> +	msleep(20);
> 
> 	while (count) {
> 		size = min_t(size_t, count, QCA_DFU_PACKET_LEN);

Regards

Marcel