[PATCH v1] Revert "Bluetooth: core: Fix missing power_on work cancel on HCI close"

From: Max Krummenacher
Date: Tue Jun 14 2022 - 14:17:44 EST


From: Max Krummenacher <max.krummenacher@xxxxxxxxxxx>

This reverts commit ff7f2926114d3a50f5ffe461a9bce8d761748da5.

The commit ff7f2926114d ("Bluetooth: core: Fix missing power_on work
cancel on HCI close") introduced between v5.18 and v5.19-rc1 makes
going to suspend freeze. v5.19-rc2 is equally affected.

This has been seen on a Colibri iMX6ULL WB which has a Marvell 8997
based WiFi / Bluetooth module connected over SDIO.

With 'v5.18' or 'v5.19-rc1 with said commit reverted' a suspend/resume
cycle looks as follows and the device is functional after the resume:

root@imx6ull:~# rfkill
ID TYPE DEVICE SOFT HARD
0 bluetooth hci0 blocked unblocked
1 wlan phy0 blocked unblocked
root@imx6ull:~# echo enabled > /sys/class/tty/ttymxc0/power/wakeup
root@imx6ull:~# date;echo mem > /sys/power/state;date
Tue Jun 14 14:43:03 UTC 2022
[ 6393.464497] PM: suspend entry (deep)
[ 6393.529398] Filesystems sync: 0.064 seconds
[ 6393.594006] Freezing user space processes ... (elapsed 0.015 seconds) done.
[ 6393.610266] OOM killer disabled.
[ 6393.610285] Freezing remaining freezable tasks ... (elapsed 0.013 seconds) done.
[ 6393.623727] printk: Suspending console(s) (use no_console_suspend to debug)

~~ suspended until console initiates the resume

[ 6394.023552] fec 20b4000.ethernet eth0: Link is Down
[ 6394.049902] PM: suspend devices took 0.300 seconds
[ 6394.091654] Disabling non-boot CPUs ...
[ 6394.565896] PM: resume devices took 0.440 seconds
[ 6394.681350] OOM killer enabled.
[ 6394.681369] Restarting tasks ... done.
[ 6394.741157] random: crng reseeded on system resumption
[ 6394.813135] PM: suspend exit
Tue Jun 14 14:43:11 UTC 2022
[ 6396.403873] fec 20b4000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx
[ 6396.404347] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
root@imx6ull:~#

With 'v5.19-rc1' suspend freezes in the suspend phase, i.e. power
consumption is not lowered and no wakeup source initiates a wakup.

root@imx6ull:~# rfkill
ID TYPE DEVICE SOFT HARD
0 bluetooth hci0 blocked unblocked
1 wlan phy0 blocked unblocked
root@imx6ull:~# echo enabled > /sys/class/tty/ttymxc0/power/wakeup
root@imx6ull:~# date;echo mem > /sys/power/state;date
Tue Jun 14 12:40:38 UTC 2022
[ 122.476333] PM: suspend entry (deep)
[ 122.556012] Filesystems sync: 0.079 seconds

~~ no further kernel output

If one first unbinds the bluetooth device driver, suspend / resume works
as expected also with 'v5.19-rc1':

root@imx6ull:~# echo mmc1:0001:2 > /sys/bus/sdio/drivers/btmrvl_sdio/unbind
root@imx6ull:~# rfkill
ID TYPE DEVICE SOFT HARD
1 wlan phy0 blocked unblocked
root@imx6ull:~# echo enabled > /sys/class/tty/ttymxc0/power/wakeup
root@imx6ull:~# date;echo mem > /sys/power/state;date
Tue Jun 14 14:59:26 UTC 2022
[ 123.530310] PM: suspend entry (deep)
[ 123.595432] Filesystems sync: 0.064 seconds
[ 123.672478] Freezing user space processes ... (elapsed 0.028 seconds) done.
[ 123.701848] OOM killer disabled.
[ 123.701869] Freezing remaining freezable tasks ... (elapsed 0.007 seconds) done.
[ 123.709993] printk: Suspending console(s) (use no_console_suspend to debug)
[ 124.097772] fec 20b4000.ethernet eth0: Link is Down
[ 124.124795] PM: suspend devices took 0.280 seconds
[ 124.165893] Disabling non-boot CPUs ...
[ 124.632959] PM: resume devices took 0.430 seconds
[ 124.750164] OOM killer enabled.
[ 124.750187] Restarting tasks ... done.
[ 124.827899] random: crng reseeded on system resumption
[ 124.923183] PM: suspend exit
Tue Jun 14 14:59:31 UTC 2022
[ 127.520321] fec 20b4000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx
[ 127.520514] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
root@imx6ull:~#

Signed-off-by: Max Krummenacher <max.krummenacher@xxxxxxxxxxx>

---

net/bluetooth/hci_core.c | 2 ++
net/bluetooth/hci_sync.c | 1 -
2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 59a5c1341c26..19df3905c5f8 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -2675,6 +2675,8 @@ void hci_unregister_dev(struct hci_dev *hdev)
list_del(&hdev->list);
write_unlock(&hci_dev_list_lock);

+ cancel_work_sync(&hdev->power_on);
+
hci_cmd_sync_clear(hdev);

if (!test_bit(HCI_QUIRK_NO_SUSPEND_NOTIFIER, &hdev->quirks))
diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index 286d6767f017..1739e8cb3291 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -4088,7 +4088,6 @@ int hci_dev_close_sync(struct hci_dev *hdev)

bt_dev_dbg(hdev, "");

- cancel_work_sync(&hdev->power_on);
cancel_delayed_work(&hdev->power_off);
cancel_delayed_work(&hdev->ncmd_timer);

--
2.20.1