Commit Graph

5 Commits

Author SHA1 Message Date
Sergey Ryazanov
ca374290aa wwan: core: support default netdev creation
Most, if not each WWAN device driver will create a netdev for the
default data channel. Therefore, add an option for the WWAN netdev ops
registration function to create a default netdev for the WWAN device.

A WWAN device driver should pass a default data channel link id to the
ops registering function to request the creation of a default netdev, or
a special value WWAN_NO_DEFAULT_LINK to inform the WWAN core that the
default netdev should not be created.

For now, only wwan_hwsim utilize the default link creation option. Other
drivers will be reworked next.

Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
CC: M Chetan Kumar <m.chetan.kumar@intel.com>
CC: Intel Corporation <linuxwwan@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 10:01:16 -07:00
Sergey Ryazanov
9f0248ea47 wwan: core: no more hold netdev ops owning module
The WWAN netdev ops owner holding was used to protect from the
unexpected memory disappear. This approach causes a dependency cycle
(driver -> core -> driver) and effectively prevents a WWAN driver
unloading. E.g. WWAN hwsim could not be unloaded until all simulated
devices are removed:

~# modprobe wwan_hwsim devices=2
~# lsmod | grep wwan
wwan_hwsim             16384  2
wwan                   20480  1 wwan_hwsim
~# rmmod wwan_hwsim
rmmod: ERROR: Module wwan_hwsim is in use
~# echo > /sys/kernel/debug/wwan_hwsim/hwsim0/destroy
~# echo > /sys/kernel/debug/wwan_hwsim/hwsim1/destroy
~# lsmod | grep wwan
wwan_hwsim             16384  0
wwan                   20480  1 wwan_hwsim
~# rmmod wwan_hwsim

For a real device driver this will cause an inability to unload module
until a served device is physically detached.

Since the last commit we are removing all child netdev(s) when a driver
unregister the netdev ops. This allows us to permit the driver
unloading, since any sane driver will call ops unregistering on a device
deinitialization. So, remove the holding of an ops owner to make it
easier to unload a driver module. The owner field has also beed removed
from the ops structure as there are no more users of this field.

Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 10:01:16 -07:00
Sergey Ryazanov
f842f48891 wwan_hwsim: support network interface creation
Add support for networking interface creation via the WWAN core by
registering the WWAN netdev creation ops for each simulated WWAN device.
Implemented minimalistic netdev support where the xmit callback just
consumes all egress skbs.

This should help with WWAN network interfaces creation testing.

Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 10:01:16 -07:00
Sergey Ryazanov
9ee23f48f6 wwan_hwsim: add debugfs management interface
wwan_hwsim creates and removes simulated control ports on module loading
and unloading. It would be helpful to be able to create/remove devices
and ports at run-time to trigger wwan port (un-)register actions without
module reloading.

Some simulator objects (e.g. ports) do not have the underling device and
it is not possible to fully manage the simulator via sysfs. wwan_hsim
intend for developers, so implement it as a self-contained debugfs based
management interface.

Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-08 14:33:43 -07:00
Sergey Ryazanov
f36a111a74 wwan_hwsim: WWAN device simulator
This driver simulates a set of WWAN device with a set of AT control
ports. It can be used to test WWAN kernel framework as well as user
space tools.

Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-08 14:33:43 -07:00