Purge the rx queue as soon as a user closes the port, just after the
port stop callback invocation. This is to prevent feeding a user that
will open the port next time with outdated and possibly unrelated
data.
While at it also remove the odd skb_queue_purge() call in the port
device destroy callback. The queue will be purged just before the
callback is ivoncated in the wwan_remove_port() function.
Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is not unreasonable to assume that users will use terminal emulation
software to communicate directly with a WWAN device over the AT port.
But terminal emulators will refuse to work with a device that does not
support terminal IOCTLs (e.g. TCGETS, TCSETS, TIOCMSET, etc.). To make
it possible to interact with the WWAN AT port using a terminal emulator,
implement a minimal set of terminal IOCTLs.
The implementation is rather stub, no passed data are actually used to
control a port behaviour. An obtained configuration is kept inside the
port structure and returned back by a request. The latter is done to
fool a program that will test the configuration status by comparing the
readed back data from the device with earlier configured ones.
Tested with fresh versions of minicom and picocom terminal apps.
MBIM, QMI and other ports for binary protocols can hardly be considered
a terminal device, so terminal IOCTLs are only implemented for the AT
port.
Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is quite common for a userpace program to fetch the buffered amount
of data in the rx queue to avoid the read block. Implement the TIOCINQ
ioctl to make the migration to the WWAN port usage smooth.
Despite the fact that the read call will return no more data than the
size of a first skb in the queue, TIOCINQ returns the entire amount of
buffered data (sum of all queued skbs). This is done to prevent the
breaking of programs that optimize reading, avoiding it if the buffered
amount of data is too small.
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>
Currently, we limit the total ports number to 256. It is quite common
for PBX or SMS gateway to be equipped with a lot of modems. In now days,
a modem could have 2-4 control ports or even more, what only accelerates
the ports exhausing rate.
To avoid facing the port number limitation issue reports, increase the
limit up the maximum number of minors (i.e. up to 1 << MINORBITS).
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>
At the moment, the port name is allocated based on the parent device
name, port id and the port type. Where the port id specifies nothing but
the ports registration order and is only used to make the port name
unique.
Most likely, to configure a WWAN device, the user will look for a port
of a specific type (e.g. AT port or MBIM port, etc.). The current naming
scheme can make it difficult to find a port of a specific type.
Consider a WWAN device that has 3 ports: AT port, MBIM port, and another
one AT port. With the global port index, the port names will be:
* wwan0p1at
* wwan0p2mbim
* wwan0p3at
To find the MBIM port, user should know in advance the device ports
composition (i.e. the user should know that the MBIM port is the 2nd
one) or carefully examine the whole ports list. It is not unusual for
USB modems to have a different composition, even if they are build on a
same chipset. Moreover, some modems able to change the ports composition
based on the user's configuration. All this makes port names fully
unpredictable.
To make naming more user-friendly, remove the global port id and
enumerate ports by its type. E.g.:
* wwan0p1at -> wwan0at0
* wwan0p2mbim -> wwan0mbim0
* wwan0p3at -> wwan0at1
With this naming scheme, the first AT port name will always be wwanXat0,
the first MBIM port name will always be wwanXmbim0, etc.
Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Usually a device name is spelled in lowercase, let us follow this
practice in the WWAN subsystem as well. The bottom line is that such
name is easier to type.
To keep the device type attribute contents more natural (i.e., spell
abbreviations in uppercase), while making the device name lowercase,
turn the port type strings array to an array of structure that contains
both the port type name and the device name suffix.
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>
This array is indexed by port type. Make it self-descriptive by using
the port type enum values as indices in the array initializer.
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>
It is quite unusual when some value can not be equal to a defined range
max value. Also most subsystems defines FOO_TYPE_MAX as a maximum valid
value. So turn the WAN_PORT_MAX meaning from the number of supported
port types to the maximum valid port type.
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>
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>
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>
Add index sysfs attribute for WWAN devices. This index is used to
uniquely indentify and reference a WWAN device. 'index' is the
attribute name that other device classes use (wireless, v4l2-dev,
rfkill, etc...).
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The port type is by default part of the WWAN port device name.
However device name can not be considered as a 'stable' API and
may be subject to change in the future. This change adds a proper
device attribute that can be used to determine the WWAN protocol/
type.
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ensure that the poll system call returns proper error flags when port
is removed (nullified port ops), allowing user side to properly fail,
without further read or write.
Fixes: 9a44c1cc63 ("net: Add a WWAN subsystem")
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The mhi_wwan_rx_budget_dec function is supposed to return true if
RX buffer budget has been successfully decremented, allowing to queue
a new RX buffer for transfer. However the current implementation is
broken when RX budget is '1', in which case budget is decremented but
false is returned, preventing to requeue one buffer, and leading to
RX buffer starvation.
Fixes: fa588eba63 ("net: Add Qcom WWAN control driver")
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
bit operation helpers such as test_bit, clear_bit, etc take bit
position as parameter and not value. Current usage causes double
shift => BIT(BIT(0)). Fix that in wwan_core and mhi_wwan_ctrl.
Fixes: 9a44c1cc63 ("net: Add a WWAN subsystem")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The MHI WWWAN control driver allows MHI QCOM-based modems to expose
different modem control protocols/ports via the WWAN framework, so that
userspace modem tools or daemon (e.g. ModemManager) can control WWAN
config and state (APN config, SMS, provider selection...). A QCOM-based
modem can expose one or several of the following protocols:
- AT: Well known AT commands interactive protocol (microcom, minicom...)
- MBIM: Mobile Broadband Interface Model (libmbim, mbimcli)
- QMI: QCOM MSM/Modem Interface (libqmi, qmicli)
- QCDM: QCOM Modem diagnostic interface (libqcdm)
- FIREHOSE: XML-based protocol for Modem firmware management
(qmi-firmware-update)
Note that this patch is mostly a rework of the earlier MHI UCI
tentative that was a generic interface for accessing MHI bus from
userspace. As suggested, this new version is WWAN specific and is
dedicated to only expose channels used for controlling a modem, and
for which related opensource userpace support exist.
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This change introduces initial support for a WWAN framework. Given the
complexity and heterogeneity of existing WWAN hardwares and interfaces,
there is no strict definition of what a WWAN device is and how it should
be represented. It's often a collection of multiple devices that perform
the global WWAN feature (netdev, tty, chardev, etc).
One usual way to expose modem controls and configuration is via high
level protocols such as the well known AT command protocol, MBIM or
QMI. The USB modems started to expose them as character devices, and
user daemons such as ModemManager learnt to use them.
This initial version adds the concept of WWAN port, which is a logical
pipe to a modem control protocol. The protocols are rawly exposed to
user via character device, allowing straigthforward support in existing
tools (ModemManager, ofono...). The WWAN core takes care of the generic
part, including character device management, and relies on port driver
operations to receive/submit protocol data.
Since the different devices exposing protocols for a same WWAN hardware
do not necessarily know about each others (e.g. two different USB
interfaces, PCI/MHI channel devices...) and can be created/removed in
different orders, the WWAN core ensures that all WAN ports contributing
to the 'whole' WWAN feature are grouped under the same virtual WWAN
device, relying on the provided parent device (e.g. mhi controller,
USB device). It's a 'trick' I copied from Johannes's earlier WWAN
subsystem proposal.
This initial version is purposely minimalist, it's essentially moving
the generic part of the previously proposed mhi_wwan_ctrl driver inside
a common WWAN framework, but the implementation is open and flexible
enough to allow extension for further drivers.
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sergey Ryazanov