Re: [RFC PATCH v6 0/5] Bluetooth: Handle system suspend gracefully

[Marcel Holtmann <marcel@holtmann.org>]

Hi Abhishek,

> This patch series prepares the Bluetooth controller for system suspend
> by disconnecting all devices and preparing the event filter and LE
> whitelist with devices that can wake the system from suspend.
> 
> The main motivation for doing this is so we can enable Bluetooth as
> a wake up source during suspend without it being noisy. Bluetooth should
> wake the system when a HID device receives user input but otherwise not
> send any events to the host.
> 
> This patch series was tested on several Chromebooks with both btusb and
> hci_serdev on kernel 4.19. The set of tests was basically the following:
> * Reconnects after suspend succeed
> * HID devices can wake the system from suspend (needs some related bluez
>  changes to call the Set Wake Capable management command)
> * System properly pauses and unpauses discovery + advertising around
>  suspend
> * System does not wake from any events from non wakeable devices
> 
> Series 2 has refactored the change into multiple smaller commits as
> requested. I tried to simplify some of the whitelist filtering edge
> cases but unfortunately it remains quite complex.
> 
> Series 3 has refactored it further and should have resolved the
> whitelisting complexity in series 2.
> 
> Series 4 adds a fix to check for powered down and powering down adapters.
> 
> Series 5 moves set_wake_capable to the last patch in the series and
> changes BT_DBG to bt_dev_dbg.
> 
> Please review and provide any feedback.
> 
> Thanks
> Abhishek
> 
> 
> Changes in v6:
> * Removed unused variables in hci_req_prepare_suspend
> * Add int old_state to this patch
> 
> Changes in v5:
> * Convert BT_DBG to bt_dev_dbg
> * Added wakeable list and changed BT_DBG to bt_dev_dbg
> * Add wakeable to hci_conn_params and change BT_DBG to bt_dev_dbg
> * Changed BT_DBG to bt_dev_dbg
> * Wakeable entries moved to other commits
> * Patch moved to end of series
> 
> Changes in v4:
> * Added check for mgmt_powering_down and hdev_is_powered in notifier
> 
> Changes in v3:
> * Refactored to only handle BR/EDR devices
> * Split LE changes into its own commit
> * Added wakeable property to le_conn_param
> * Use wakeable list for BR/EDR and wakeable property for LE
> 
> Changes in v2:
> * Moved pm notifier registration into its own patch and moved params out
>  of separate suspend_state
> * Refactored filters and whitelist settings to its own patch
> * Refactored update_white_list to have clearer edge cases
> * Add connected devices to whitelist (previously missing corner case)
> * Refactored pause discovery + advertising into its own patch
> 
> Abhishek Pandit-Subedi (5):
>  Bluetooth: Handle PM_SUSPEND_PREPARE and PM_POST_SUSPEND
>  Bluetooth: Handle BR/EDR devices during suspend
>  Bluetooth: Handle LE devices during suspend
>  Bluetooth: Pause discovery and advertising during suspend
>  Bluetooth: Add mgmt op set_wake_capable
> 
> include/net/bluetooth/hci.h      |  17 +-
> include/net/bluetooth/hci_core.h |  43 ++++
> include/net/bluetooth/mgmt.h     |   7 +
> net/bluetooth/hci_core.c         | 102 ++++++++++
> net/bluetooth/hci_event.c        |  24 +++
> net/bluetooth/hci_request.c      | 331 ++++++++++++++++++++++++++-----
> net/bluetooth/hci_request.h      |   2 +
> net/bluetooth/mgmt.c             |  92 +++++++++
> 8 files changed, 558 insertions(+), 60 deletions(-)

patches 1-4 have been applied to bluetooth-next tree.

I skipped patch 5 since now we have to discuss how best the API for setting the wakeable devices will be. Care to start up a discussion thread for that?

Regards

Marcel