linux-toradex.git/drivers/bluetooth/hci_h5.c, branch v5.18

Bluetooth: hci_uart: add missing NULL check in h5_enqueue

2022-03-18T16:12:07+00:00

Syzbot hit general protection fault in __pm_runtime_resume(). The problem
was in missing NULL check.

hu->serdev can be NULL and we should not blindly pass &serdev->dev
somewhere, since it will cause GPF.

Reported-by: syzbot+b9bd12fbed3485a3e51f@syzkaller.appspotmail.com
Fixes: d9dd833cf6d2 ("Bluetooth: hci_h5: Add runtime suspend")
Signed-off-by: Pavel Skripkin 
Signed-off-by: Marcel Holtmann

Bluetooth: hci_h5: Add power reset via gpio in h5_btrtl_open

2022-01-26T13:39:35+00:00

Add power reset for bluetooth via enable-gpios in h5_btrtl_open function.

While testing the RTL8822CS SDIO WiFi/BT adapter, it was found that in
some cases the kernel could not initialize BT firmware. However,
manually resetting the adapter via gpio (off/on sequence) allows it to
start correctly.
Apparently, when the system starts, the adapter is in an undefined state
(including unknown gpio state after starting uboot). A forced reset helps
to initialize the adapter in most cases. It has been found experimentally
that 100 ms is sufficient for a reset.

Signed-off-by: Vyacheslav Bocharov 
Signed-off-by: Marcel Holtmann

Bluetooth: hci_h5: directly return hci_uart_register_device() ret-val

2021-09-24T09:48:02+00:00

Since the hci_uart_register_device() call is the last thing we do in
h5_serdev_probe() we can simply directly return its return-value.

Cc: Archie Pusaka 
Suggested-by: Archie Pusaka 
Signed-off-by: Hans de Goede 
Signed-off-by: Marcel Holtmann

Bluetooth: hci_h5: Fix (runtime)suspend issues on RTL8723BS HCIs

2021-09-24T09:35:53+00:00

The recently added H5_WAKEUP_DISABLE h5->flags flag gets checked in
h5_btrtl_open(), but it gets set in h5_serdev_probe() *after*
calling  hci_uart_register_device() and thus after h5_btrtl_open()
is called, set this flag earlier.

Also on devices where suspend/resume involves fully re-probing the HCI,
runtime-pm suspend should not be used, make the runtime-pm setup
conditional on the H5_WAKEUP_DISABLE flag too.

This fixes the HCI being removed and then re-added every 10 seconds
because it was being reprobed as soon as it was runtime-suspended.

Fixes: 66f077dde749 ("Bluetooth: hci_h5: add WAKEUP_DISABLE flag")
Fixes: d9dd833cf6d2 ("Bluetooth: hci_h5: Add runtime suspend")
Signed-off-by: Hans de Goede 
Reviewed-by: Archie Pusaka 
Signed-off-by: Marcel Holtmann

Bluetooth: hci_uart: fix GPF in h5_recv

2021-09-10T07:38:43+00:00

Syzbot hit general protection fault in h5_recv(). The problem was in
missing NULL check.

hu->serdev can be NULL and we cannot blindly pass &serdev->dev
somewhere, since it can cause GPF.

Fixes: d9dd833cf6d2 ("Bluetooth: hci_h5: Add runtime suspend")
Reported-and-tested-by: syzbot+7d41312fe3f123a6f605@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin 
Signed-off-by: Marcel Holtmann

Bluetooth: hci_h5: Add runtime suspend

2021-07-23T12:10:23+00:00

This patch allows the controller to suspend after a short period of
inactivity.

Signed-off-by: Archie Pusaka 
Reviewed-by: Abhishek Pandit-Subedi 
Reviewed-by: Hilda Wu 
Signed-off-by: Marcel Holtmann

Bluetooth: hci_h5: btrtl: Maintain flow control if wakeup is enabled

2021-07-23T12:10:23+00:00

For chips that doesn't reset on suspend, we need to provide the correct
value of flow_control when it resumes. Therefore, store the flow
control value when reading from the config file to be reused upon
suspend.

Signed-off-by: Archie Pusaka 
Reviewed-by: Abhishek Pandit-Subedi 
Reviewed-by: Hilda Wu 
Signed-off-by: Marcel Holtmann

Bluetooth: hci_h5: add WAKEUP_DISABLE flag

2021-07-23T12:10:23+00:00

Some RTL chips resets the FW on suspend, so wakeup is disabled on
those chips. This patch introduces this WAKEUP_DISABLE flag so that
chips that doesn't reset FW on suspend can leave the flag unset and
is allowed to wake the host.

This patch also left RTL8822 WAKEUP_DISABLE flag unset, therefore
allowing it to wake the host, and preventing reprobing on resume.

Signed-off-by: Archie Pusaka 
Reviewed-by: Abhishek Pandit-Subedi 
Reviewed-by: Hilda Wu 
Signed-off-by: Marcel Holtmann

Bluetooth: hci_h5: Disable the hci_suspend_notifier for btrtl devices

2021-07-22T14:06:09+00:00

The hci_suspend_notifier which was introduced last year, is causing
problems for uart attached btrtl devices. These devices may loose their
firmware and their baudrate setting over a suspend/resume.

Since we don't even know the baudrate after a suspend/resume recovering
from this is tricky. The driver solves this by treating these devices
the same as USB BT HCIs which drop of the bus during suspend.

Specifically the driver:
1. Simply unconditionally turns the device fully off during
   system-suspend to save maximum power.
2. Calls device_reprobe() from a workqueue to fully re-init the device
   from scratch on system-resume (unregistering the old HCI and
   registering a new HCI).

This means that these devices do not benefit from the suspend / resume
handling work done by the hci_suspend_notifier. At best this unnecessarily
adds some time to the suspend/resume time.

But in practice this is actually causing problems:

1. These btrtl devices seem to not like the HCI_OP_WRITE_SCAN_ENABLE(
SCAN_DISABLED) request being send to them when entering the
BT_SUSPEND_CONFIGURE_WAKE state. The same request send on
BT_SUSPEND_DISCONNECT works fine, but the second one send (unnecessarily?)
from the BT_SUSPEND_CONFIGURE_WAKE transition causes the device to hang:

[  573.497754] PM: suspend entry (s2idle)
[  573.554615] Filesystems sync: 0.056 seconds
[  575.837753] Bluetooth: hci0: Timed out waiting for suspend events
[  575.837801] Bluetooth: hci0: Suspend timeout bit: 4
[  575.837925] Bluetooth: hci0: Suspend notifier action (3) failed: -110

2. The PM_POST_SUSPEND / BT_RUNNING transition races with the
driver-unbinding done by the device_reprobe() work.
If the hci_suspend_notifier wins the race it is talking to a dead
device leading to the following errors being logged:

[  598.686060] Bluetooth: hci0: Timed out waiting for suspend events
[  598.686124] Bluetooth: hci0: Suspend timeout bit: 5
[  598.686237] Bluetooth: hci0: Suspend notifier action (4) failed: -110

In both cases things still work, but the suspend-notifier is causing
these ugly errors getting logged and ut increase both the suspend- and
the resume-time by 2 seconds.

This commit avoids these problems by disabling the hci_suspend_notifier.

Cc: Luiz Augusto von Dentz 
Cc: Vasily Khoruzhick 
Cc: Abhishek Pandit-Subedi 
Signed-off-by: Hans de Goede 
Signed-off-by: Marcel Holtmann

Bluetooth: hci_h5: Add RTL8822CS capabilities

2021-06-26T05:12:34+00:00

RTL8822 chipset supports WBS, and this information is conveyed in
btusb.c. However, the UART driver doesn't have this information just
yet.

Signed-off-by: Archie Pusaka 
Reviewed-by: Abhishek Pandit-Subedi 
Signed-off-by: Marcel Holtmann