RE: [PATCH v3] Bluetooth: btusb: Fix suspend issue for Realtek devices
From: Max Chou
Date: Mon Aug 19 2019 - 05:29:11 EST
Dear Kernel Maintainer Marcel,
Sorry for the inconvenience. For the original target, this patch is edited for low power consumption hence controller should not receive DEVICE_REMOTE_WAKE_UP that it's able to save power in suspend mode because BT wake-up function is disabled.
In upstream driver, there should be higher priority for function rather than performance. In other words, this patch can meet the low power consumption in suspend mode but will lose BT wake-up function. It is not a good idea for that. Please help to revert this modification.
From: Marcel Holtmann <marcel@xxxxxxxxxxxx>
Sent: Wednesday, August 14, 2019 9:54 PM
To: alex_lu <alex_lu@xxxxxxxxxxxxxx>
Cc: Johan Hedberg <johan.hedberg@xxxxxxxxx>; linux-bluetooth@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Max Chou <max.chou@xxxxxxxxxxx>
Subject: Re: [PATCH v3] Bluetooth: btusb: Fix suspend issue for Realtek devices
> From the perspective of controller, global suspend means there is no
> SET_FEATURE (DEVICE_REMOTE_WAKEUP) and controller would drop the
> firmware. It would consume less power. So we should not send this kind
> of SET_FEATURE when host goes to suspend state.
> Otherwise, when making device enter selective suspend, host should
> send SET_FEATURE to make sure the firmware remains.
> Signed-off-by: Alex Lu <alex_lu@xxxxxxxxxxxxxx>
> Changes in v3:
> - Change to fit for bluetooth-next
> Changes in v2:
> - Change flag to be more descriptive
> - Delete pointless #ifdef CONFIG_BT_HCIBTUSB_RTL and #endif
> drivers/bluetooth/btusb.c | 34 ++++++++++++++++++++++++++++++----
> 1 file changed, 30 insertions(+), 4 deletions(-)
patch has been applied to bluetooth-next tree.
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