Only TCP sockets should send a NULL packet
if the server closes the connection or there
is a socket error.
UDP sockets do not need to do this because
they are connectionless.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
Fix hard fault due to NULL being passed as argument into
rssi_handler, which now derives the gsm_modem struct pointer from
the argument.
Signed-off-by: Yong Cong Sin <yongcong.sin@gmail.com>
gsm_ppp_stop should cancel possible running work items.
Signed-off-by: Yong Cong Sin <yongcong.sin@gmail.com>
Signed-off-by: Wouter Cappelle <wouter.cappelle@crodeon.com>
The 'work' argument of a delayable work's handler should be
converted to delayable work before passing into the CONTAINER_OF
macro.
Signed-off-by: Yong Cong Sin <yongcong.sin@gmail.com>
The driver performs AT commands configurations using the
system workqueue, this can delay the workqueue by up to 6
seconds to wait for the modem replies, which isn't ideal.
This PR creates a dedicated workqueue for the gsm, and
provides a helper function to reschedule work items to the
gsm workqueue.
Signed-off-by: Yong Cong Sin <yongcong.sin@gmail.com>
Implemented driver for the simcom sim7080 modem.
This driver features Socket offloading, TCP, UDP, DNS,
SMS, GPS and FTP.
Signed-off-by: Lukas Gehreke <lk.gehreke@gmail.com>
The device PM subsystem _depends_ on device, not vice-versa. Devices
only hold a reference to struct pm_device now, and initialize this
reference with the value provided in Z_DEVICE_DEFINE. This requirement
can be solved with a forward struct declaration, meaning there is no
need to include device PM headers.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
Since drivers implement a callback based on action and not the state,
we should be using the API based on the action instead of the one based
on the state.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
The modem sockets poll implementation does not allow
a combination of poll on modem sockets and on other sockets
like eventfd. This blocks trivial application signalling. Current
users are using a poll timeout, which needs to check if other
work needs to be done in the thread (eg: lwm2m engine).
To allow proper signalling with eventfd, the non offload poll
methods needs to work for the modem sockets.
This commit is implementing this for POLLIN.
Signed-off-by: Wouter Cappelle <wouter.cappelle@crodeon.com>
The previous bf68b67 commit incorrectly passes minfo.mdm_rssi
value to the modem context data_rssi member during the driver
initialization which causes the `modem info` shell command
to return 0 as RSSI value. Fix that by changing data_rssi
modem ctx member to a pointer that is assigned to the RSSI
variable stored within the modem driver context structure.
Signed-off-by: Bartosz Bilas <bartosz.bilas@hotmail.com>
CONFIG_UART_MUX_DEVICE_NAME is used as a prefix for the uart muxes
name. Pointer comparison will always return false
Fix#39774
Signed-off-by: Guillaume Lager <g.lager@innoseis.com>
drivers: modem: gsm: Quectel EC21 and BG9x act as a gsm modem without
problem, but COPS commands can returns just one value with 'mode'.
Format and oper are not mandatory. This modification reads 'mode'.
Also a modification on modem_cmd_read_cops_cmd is needed.
Signed-off-by: Jair Jack <jack@icatorze.com.br>
Add RSSI member into gsm_ppp_modem_info structure in order to
get that information using the gsm_ppp_modem_info function.
Signed-off-by: Bartosz Bilas <b.bilas@grinn-global.com>
Make modem_info structure public in order to allow the user
to get modem information using gsm_ppp_modem_info function.
Move modem info query commands into separate function
that's called only once during gsm configuring because
there is no necessity to re-querying modem since
they should not change.
Signed-off-by: Bartosz Bilas <b.bilas@grinn-global.com>
With the introduction of `EXPERIMENTAL` and `WARN_EXPERIMENTAL` in
Zephyr all drivers settings having `[EXPERIMENTAL]` in their
prompt has has been updated to include `select EXPERIMENTAL` so that
developers can enable warnings when experimental features are enabled.
Signed-off-by: Torsten Rasmussen <Torsten.Rasmussen@nordicsemi.no>
The current modem sockets poll implementation has 2 limitations
as of today:
- not following posix spec wrt timeout of -1 (should be forever,
but as today it's was returning immediately)
- not able to poll from multiple threads on different sockets
on the same modem.
This pull request should implement these limitations.
Signed-off-by: Wouter Cappelle <wouter.cappelle@crodeon.com>
When creating a socket, be sure to check the address
family and set the correct address family option in
the AT command.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
Allow the user to register function callbacks that
are executed during gsm modem configuring and stopping.
Signed-off-by: Bartosz Bilas <bartosz.bilas@hotmail.com>
Changes the modem_context_sprint_ip addr to write into a provided
buffer. This approach fixes a referencing to a non existing stack
variable, without using a lot of stack space.
Tested using the by building all used modems and tested on HW using
IPv4.
Fixes: #38459
Signed-off-by: Sjors Hettinga <s.a.hettinga@gmail.com>
When creating a socket, all of the registered socket implementation are
processed in a sequence, allowing to find appropriate socket
implementation for specified family/type/protocol. So far however,
the order of processing was not clearly defined, leaving ambiguity if
multiple implmentations supported the same set of parameters.
Fix this, by registering socket priority along with implementation. This
makes the processing order of particular socket implementations
explicit, giving more flexibility to the user, for example when it's
neeed to prioritze one implementation over another if they support the
same set of parameters.
Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
Fixes: #38403
Removing unneeded `imply GPIO` and `CONFIG_GPIO=y` occurrences where no
files are added to the gpio zephyr library.
Also removed `CONFIG_GPIO=y` occurences where this is handled by
defconfigs for the soc or board.
Selection of GPIO without selecting any drivers results in the warning:
> No SOURCES given to Zephyr library: drivers__gpio
>
> Excluding target from build.
Signed-off-by: Torsten Rasmussen <Torsten.Rasmussen@nordicsemi.no>
The interrupt config flags for an IO should be separate
from the standard IO configs because the interrupt config
is a separate API.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
Add support for Quectel modem in gsm_ppp modem driver.
The CMUX cmd is based on MUX application notes v1.0(2020-09-22)
for BG95, BG77 and BG600L. Tested and working on EC21e.
As the gsm_ppp doesn't do power control, it is required to power
on the modem manually in the application.
Signed-off-by: Yong Cong Sin <yongcong.sin@gmail.com>
Ensure the GPRS connection APN settings match the PDP
context. This it best to ensure proper IP connectivity.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
Ensure that the IP family is synchronized between the PDP
context and the GPRS connection.
There were cases where they could get out of sync.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
Assign the IPv6 address from the LTE network to the
network iface.
Configure DNS resolver with IPv6 DNS address from the
LTE network.
Fix socket AT commands to account for IPv6 addresses.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
In the DNS work callback ensure the iface is up
(on the LTE network) before trying to reconfigure the
DNS resolver with the DNS address.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
Fix power-save-mode (PSM) operation.
When in PSM, do not bring the networking interface down
when an out-of-coverage event occurs.
When PSM goes into hibernate, this will cause an
out-of-coverage event to occur, even though the device
still has access to service.
Keeping the networking interface in the up state
allows an app to send data whenever it needs to.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
Using DTR to control sleep modes is a legacy mode
of operation. Remove control of DTR IO.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
Sleep mode 0 (driven by DTR) is only recommended for use
as a legacy option.
Sleep mode 1 is recommend by Sierra Wireless.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
Snprintf calls should be avoid when not necessary, instead snprintk
should be used as it offers the same functionnalities at a lower cost
in flash.
Signed-off-by: Xavier Chapron <xavier.chapron@stimio.fr>
Position over LTE (PoLTE) can be used to locate a device as
an alternative to GNSS.
Increase RX thread stack size for PoLTE processing.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
Allow application control for starting modem driver.
This allows network attach to be randomized.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
For low power operation, set the IP connection reconfig
flag when receiving a startup report.
This will ensure the GPRS connection is reconfigured
before any socket operations take place.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
Allow the driver to run if a SIM card is not present.
This allows public HL7800 APIs like firmware updates
to be used even if no network is available.
Remove duplicate query ICCID command.
Signed-off-by: Andrew Hedin <andrew.hedin@lairdconnect.com>
bugfix: NULL termination is required by
dns_resolve_reconfigure API so null terminate the DNS
server list.
Fix checkpatch warning.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
net_buf_skipcrlf() will remove all \r\n characters from the buffer.
If the data after CONNECT\r\n contained \r or \n it would
be removed, resulting in dropped data.
Fix this to only remove two bytes to ensure data is not dropped.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
Change socket RX trailer (EOF) missing to warning and
keep socket RX data instead of discarding.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
It should be "u-blox,sara-r4", because the vendor prefix for this
company is "u-blox", not "ublox".
Signed-off-by: Martí Bolívar <marti.bolivar@nordicsemi.no>
Instead of putting object files inside libzephyr.a,
simply build a separate static library as most other
driver types are doing this already.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
According to the documentation the OFF state has to be used when the
devices is fully turned off, ie, power removed. Most drivers were using
a sort of fall-through for all non-active states, leading to behaviors
not following the specifications.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
The verb tense for the suspended state was not consistent with other
states. The likely reason: state was being used as a command/action.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
The difference between low power and suspend states is a thin blur line
that is is not clear and most drivers have used indistinctly. This patch
converges to the usage of the suspend state for low power, since
contrary to the low power state, it is used by both system and runtime
device PM. The low power state is still kept, but its future is unclear
and needs some discussion.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
When building tests/drivers/build_all/modem on native_posix_64 we get:
modem_cmd_handler.c:545:9: error: ret may be used
uninitialized in this function
[-Werror=maybe-uninitialized]
Fix by adding simple initialization of ret = 0 at start of function.
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
There are currently modem_cmd_send() and modem_cmd_send_nolock()
functions, each with slightly different behavior regarding acquiring (or
not) sem_tx_lock. Introduce a generic function that will allow caller to
select behavior using flags.
While at it, add possibility to disable setting and unsetting command
handlers. This will be useful in situations when there are multiple
replies expected one after the other coming as a response to single
command. This is the case for example with ESP-AT driver, which expects
following data as response to AT+CIPSEND command:
OK
>
where 'OK' is handled by static CMD_RESP (so releasing response
semaphore right away), while '>' is handled by dynamic
CMD_HANDLER (which is releasing another semaphore). Keeping command
handlers in place allows to receive '>' without race condition because
of small period of time where command handlers are not set.
Convert modem_cmd_send_nolock() and modem_cmd_send() to static inline
functions, as they are just a specific invocation of
modem_cmd_send_ext() function.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
So far modem API used UART device names / labels. Change API to operate
on device pointers instead, so that we stop using device_get_binding()
in modem core and in some DT compatible modem drivers.
Signed-off-by: Marcin Niestroj <m.niestroj@emb.dev>
This PR addresses radio signal stength measurement during
and before PPP session. The PR provides provides facility
of readout for both +CSQ and +CESQ versions depending
upon the modems. This PR follows the idea of rssi readout
of PR#35496. Additionally, reliable Cell info update
is also ensured.
Signed-off-by: Tahir Akram <mtahirbutt@hotmail.com>
The callback is not used anymore, so just delete it from the pm_control
callback signature.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
We do not need the return value of k_sem_take() so ignore it.
Coverity-CID: 236602
Fixes#36313
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Query the numerical network operator id, location area code (LAC)
and cell id. Following AT commands are used:
AT+COPS?
AT+CEREG?
Functionality is enabled by CONFIG_MODEM_CELL_INFO=y.
Tested with uBlox SARA-R410M-02B.
Signed-off-by: Hans Wilmers <hans@wilmers.no>
Query the numerical network operator id, location area code (LAC)
and cell id. Following AT commands are used:
AT+COPS?
AT+CEREG?
Functionality is enabled by CONFIG_MODEM_CELL_INFO=y.
Tested with uBlox SARA-R410M-02B.
Signed-off-by: Hans Wilmers <hans@wilmers.no>
Implement numerical network operator id, location area code (LAC)
and cell id in modem context and modem shell.
Please note that the functionality to query these values must be
implemented in the modem driver.
Signed-off-by: Hans Wilmers <hans@wilmers.no>
The reboot option of the +KSRAT command is only
supported by newer firmware.
Add a check to determine what version of the command
to use when setting the RAT.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
The default behavior of the +KSRAT= command has
changed to not reboot the HL7800.
Adjust the command so the reboot takes place properly.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
If the modem drivers are built on a 64-bit platform we get errors with
the logging code due to use of size_t. Update to use %zX to handle this
correctly between 32-bit and 64-bit platforms.
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Remove reset pin requirement from devicetree as this
is not required for modem functionality, and is not
used in the driver anyways.
Signed-off-by: Emil Lindqvist <emil@lindq.gr>
If modem receives an IPv6 address, buffer overrun
would occur. Fix this by checking string length to
ensure what type of IP address needs to be parsed.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
Use recently introduced API, which takes care of gracefully closing any
pending DNS requests and replacing existing DNS server list with new
one.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Replace all existing deprecated API with the recommended alternative.
Be aware that this does not address architectural errors in the use
of the work API.
Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
In a previous commit, a check was added to ensure modem was properly
attached to packet service before initializing PPP. Failure to perform
this check can lead to the dreaded 'NO CARRIER' issue.
While this is a nice idea, the implementation was lacking because when
the check failed, the entire modem initialization procedure was
restarted from square one. For modems/bearers that were slow to attach,
this is potentially disastrous. The proper solution is to loop only the
'AT+CGATT?' part until it succeeds, or fails N times.
This commit implements this looping behavior (using the work queue).
Signed-off-by: Benjamin Lindqvist <benjamin.lindqvist@endian.se>
Some tools consider this as commented code because of the ifdef, so
remove that and fix a coding guideline violation.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Coverity complains about unchecked return value for `k_sem_take` which
is called with `K_FOREVER` and thus cannot expire/timeout. Explicity
ingore the return value to silence Coverity.
CID: 219676
Fixes#33019
Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
Autostarting PPP is far from controversial. There are many, many reasons
someone could have for wanting to control exactly when PPP starts. Power
management, NET_EVENT race condition avoidance and any application not
requiring constant and instant use of networking just to name a few.
This commit introduces a Kconfig setting, GSM_PPP_AUTOSTART, which
controls whether gsm_ppp should connect and initialize PPP at boot. It
is set to "y" as default to minimize surprises for legacy code.
Signed-off-by: Benjamin Lindqvist <benjamin.lindqvist@endian.se>
Added (void) cast to supress coverity report. The usage of K_FOREVER
tells me we're not interested in the returned value.
Coverity-CID: 219653
Fixes#33034
Signed-off-by: Guðni Már Gilbert <gudni.m.g@gmail.com>
Some modems, under some conditions, have a tendency to get stuck without
a connection due to cached state. We have observed this on some Simcom
LTE modems after large cellular outages. The modems are unable to escape
their cached state for some reason unless they're factory reset (or a
cache clearence is forced in some other way).
This commit allows for the modem to be factory reset at each boot. This
minimizes dependencies on external state by ensuring each power-up is as
similar as possible.
Signed-off-by: Benjamin Lindqvist <benjamin.lindqvist@endian.se>
The PDP context might be active.
If that's the case, the AT+QIACT command returns an error.
It's then not possible to succeed at setting up the module.
Furthermore, we apply the logic described in the Quectel Documentation :
- If there is an issue 3 consecutive times on activating/deactivating
the context, we restart the module.
- If the AT+QIDEAT command returns an error, we restart the module.
This PR is bug-fix aimed.
We leave parameterization of context ID for future enhancement.
Signed-off-by: Thomas LE ROUX <thomas.leroux@smile.fr>
Convert ublox-sara-r4 driver:
NET_DEVICE_OFFLOAD_INIT -> NET_DEVICE_DT_INST_OFFLOAD_DEFINE
DT label is already required, so use it and drop
CONFIG_MODEM_UBLOX_SARA_R4_NAME option.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
This wait on @ prompt was added in
fa3d586483.
The situation were the @ prompt is never received should not occurs,
however it's definitively safer to catch it instead of having a
deadlock.
Signed-off-by: Xavier Chapron <xavier.chapron@stimio.fr>
According to AT commands manual, no wait after prompt '@'
is required if using AT+USOST commmand (aka. sendto,
only used with UDP).
Signed-off-by: Emil Lindqvist <emil@lindq.gr>
z_free_fd() is called twice then you close(). For example in ublox sara
r4 driver offload_close() calls modem_socket_put() where z_free_fd() is
called first time. Then this same function is called another time in
socket.c in z_impl_zsock_close() after this function has called
offload_close() in ublox sara r4 driver. This causes socket
descriptor leak.
Fixes#26819
Signed-off-by: Akseli Peltola <peltsu1324@gmail.com>
Set NET_CONTEXT_CONNECTED when stream socket got connected. This fixes
TCP connection when using wncm14a2a modem driver, which got broken after
sockets layer started to validate net_context connection state before
allowing to receive any data.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
- Remove SYS_ prefix
- shorten POWER_MANAGEMENT to just PM
- DEVICE_POWER_MANAGEMENT -> PM_DEVICE
and use PM_ as the prefix for all PM related Kconfigs
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
There was a regression introduced when reordering function parameters
check. It is valid to pass NULL semaphore with zero timeout, so fix
parameter check to respect that.
Fixes: 67976f8686 ("drivers: modem: verify send semaphore before
taking any action")
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Previously, msghdr was handled by forwarding each msg_iov to
offload_sendto() one by one.
This is not optimal, as msg_iov payload might have been sent
simultaneously which would be faster.
With this commit, send_socket_data() expect payload to be formated as
struct msghdr which can be used directly by both offload_sendto() and
offload_sendmsg().
Signed-off-by: Xavier Chapron <xavier.chapron@stimio.fr>
This comit introduce two new Kconfig which allow to configure RSSI
polling work.
One Kconfig allow to completely disable the polling.
The other one allow to sonfigure the polling period.
Signed-off-by: Xavier Chapron <xavier.chapron@stimio.fr>
Replace hard coded wait by real detection of '@'.
This make sure that datasheet timings are correctly followed.
Signed-off-by: Xavier Chapron <xavier.chapron@stimio.fr>
Reset of the sem_response semaphore should be done before sending data.
This prevent any potential race conditions between the rx thread and the
thread running send_socket_data().
Signed-off-by: Xavier Chapron <xavier.chapron@stimio.fr>
Some data where not properly reset on socket_put() and not correctly
initialized at socket creation. Which means we were potentially re-using
data from previous use of this socket.
Signed-off-by: Xavier Chapron <xavier.chapron@stimio.fr>
Before this commit, if a socket had received data before calling the
poll function, then the poll was waiting for either new data or a
timeout.
With this fix, polled socket are check for pending data before the
semaphore wait.
Signed-off-by: Xavier Chapron <xavier.chapron@stimio.fr>
Adding support for Quectel BG95 Modem offloaded driver
to zephyr.
The driver currently implements only the
client side functions of the "socket_op_vtable", and
so cannot be used for cases where Zephyr acts as a
server. Moreover the driver only supports TCP for now.
Looking through the guides, the same driver should be
usable for BG96 (and other modems) except for the modem
boot-up sequence. Hence its named as "bg9x" instead of
"bg95".
Tested extensively with Zephyr acting as MQTT endpoint
and publishing / subscribing data to / from an MQTT
broker.
Signed-off-by: Bilal Wasim <bilalwasim676@gmail.com>
There is no point in clearing out command handlers if they were not
setup properly. Just skip to next instruction.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Command was sent first, then a semaphore was reset. This semaphore could
be released by received reply even before semaphore was reset. This is
quite unlikely, but possible result of race condition.
Move k_sem_reset() call before attempt to send command over modem
interface. This makes sure that receiving reply momentarily after
sending request will always be handled properly.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Semaphore argument is checked only after requested command is already
sent over modem interface. It makes little sense to return -EINVAL when
half of the requested operation (send) has already been done.
Check timeout and semaphore arguments just on the beginning of
function. Return -EINVAL early, before sending any data or taking any
locks.
Clear out 'sem' variable when there is no need to wait. Use this
variable later on as an indication to actually wait on semaphore or not.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
There is no reason to clenaup members of net_context structure, as those
should be (and are) managed by net_context_put() implementation.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
There is no reason to clenaup members of net_context structure, as those
should be (and are) managed by net_context_put() implementation.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Constifying global data allows to save lots of RAM. This improvement
allows to save 224 bytes of RAM when compiled on ARM, with default
configuration.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Constifying global data allows to save lots of RAM. Defining data inside
function as 'static const' allows on the other hand to save stack usage
and reduced code size (because data doesn't have to be copied on stack
in runtime).
This improvement allows to save 448 bytes of RAM and 88 bytes of ROM
when compiled on ARM, with default configuration.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
modem_cmd and setup_cmd structures are used only to store static
information about commands to be sent and replies to be
received. Reference it as const, so that it is possible to define const
instances and save some RAM space by placing those definitions entirely
in ROM.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
The commit 5e97d779bb ("device: convert DEVICE_INIT to DEVICE_DEFINE
or SYS_DEVICE_DEFINE") did not convert the gsm_ppp.c properly. The
power management parameter was not set to NULL but was pointing to
the data pointer.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Convert handful of users of DEVICE_INIT to DEVICE_DEFINE or
SYS_DEVICE_DEFINE to allow deprecation of DEVICE_INIT.
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Replaces all existing variants of value clamping with the MIN and MAX
macros with the CLAMP macro.
Signed-off-by: Trond Einar Snekvik <Trond.Einar.Snekvik@nordicsemi.no>
All net_bufs allocated to modem_cmd_handler's data->rx_buf are consumed
synchronously in ublox-sara-r4.c in the same thread. This means that
allocating them with timeout makes no sense, because timeout
will *always* be hit when there are no more buffers in net_buf_pool.
Get rid of the unnecessary timeout, as it doesn't help and just slows
down processing of incoming data, increasing possibility of data
overrun.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
All net_bufs allocated to modem_cmd_handler's data->rx_buf are consumed
synchronously in gsm_ppp.c in the same thread. This means that
allocating them with timeout makes no sense, because timeout
will *always* be hit when there are no more buffers in net_buf_pool.
Get rid of the unnecessary timeout, as it doesn't help and just slows
down processing of incoming data, increasing possibility of data
overrun.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
So far a dedicated buffer was used for data read from modem
interface. New net_bufs were allocated and filled later, which means
that data was lost when no more net_bufs were available in the pool.
Prevent data loss by allocating net_buf before attempting any read on
modem interface. Process incoming data in a loop as long as reading from
interface results in new data. Also remove dedicated buffer
(data->read_buf) and directly fill net_buf content instead. As a side
effect there are less memory copy operations and RAM usage is reduced.
Pre-allocated net_buf is now always appended to data->rx_buf. When there
was no (more) data read from interface to such net_buf, then this empty
net_buf will be on the end of data->rx_buf fragment list. Update
skipcrlf() and findcrlf() implementations to explicitly check for each
net_buf length, instead of blindly assuming them to have at least single
byte.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
cmd_handler_process() does two major things:
- reads data from modem interface and fills data->rx_buf,
- processes data in data->rx_buf.
Split implementation accordingly to two separate functions, which
improves readability (less automatic variables to follow at once) and
simplifies refactoring of each action.
No functional change was intended in this commit.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
If CONFIG_MODEM_SIM_NUMBERS is 'n' than the data_imei field of struct
modem_context doesn't exist, so add ifdef protection for that case.
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
If other threads are accessing the modem concurrently during gsm_ppp
initialization, they can easily corrupt UART comms. Normally this is not
noticable since those services are usually started only after modem
setup has been completed. But with the new gsm_ppp stop/start
functionality, the need of synchronizing concurrent access in a
structured way has arisen.
This commit ensures modem_cmd_handler is locked when concurrent access
to the modem UART would interfere with the driver, or otherwise cause
problems. Since the semaphore is not available during this period, all
essential calls to modem_cmd_send has been replaced with the non-locking
equivalents.
Signed-off-by: Benjamin Lindqvist <benjamin.lindqvist@endian.se>
A semaphore is used by modem_cmd_handler to protect against concurrent
UART access. This is only used for the duration of sending a command,
but there are cases when one wants to prevent UART access for other
reasons, such as when powering off the modem.
This commit exposes functionality for hogging this semaphore without
having to send a command. Furthermore, a non-locking equivalent for
modem_cmd_handler_setup_cmds is added which was previously missing.
Signed-off-by: Benjamin Lindqvist <benjamin.lindqvist@endian.se>
Application might need to know the GSM modem device name so
provide it in the header file.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
When PPP is muxed, using uart_poll_out resulted in each byte getting
wrapped in a muxing header. This led to UART bombardment which
can quickly cause some modems to hang and panic. This was observed
regularly using a SIMCOM7600E modem.
A perfect fix would involve rewriting ppp.c, uart_mux.c and
modem_iface_uart.c to all use another UART API, but that would be more
invasive by several orders of magnitude than this one, which utilizes
the fact that the uart_mux implementation of uart_fifo_fill does NOT
require ISR context. Since the Zephyr UART API states that the behavior
of uart_fifo_fill outside of ISR context is implementation defined, this
should be kosher.
Signed-off-by: Benjamin Lindqvist <benjamin.lindqvist@endian.se>
These changes enable applications to restart the networking stack which
was previously not possible without rebooting the device. This was a
major show-stopper because it made power management impossible, and
furthermore made it impossible to recover from a bad modem state without
rebooting.
This has been verified to work on a SIMCOM7600E modem, both with and
without CONFIG_GSM_MUX enabled.
Signed-off-by: Benjamin Lindqvist <benjamin.lindqvist@endian.se>
The char pointer that is logged could get scoped out and so should be
strduped before logging.
Signed-off-by: Benjamin Lindqvist <benjamin.lindqvist@endian.se>
Attempting to initialize PPP without first ensuring we're attached to
the network packet service will sometimes lead to "NO CARRIER" errors
when we initialize PPP with the modem. This has been observed
reproducibly on some SIMCOM7600E modems.
This commit holds off on PPP initialization until modem has reported
that it is indeed attached by using the "AT+CGATT?" command (see 3GPP TS
27.007)
Signed-off-by: Benjamin Lindqvist <benjamin.lindqvist@endian.se>
There are cases where the socket would not be closed.
offload_put function will now always close the socket
properly.
Remove error log messages as they are redundant.
on_cmd_sock_error_code handles printing errors.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
If HW flow control is enabled, then modem_context framework won't drain
UART FIFO blindly, but will stop when there is no more space in RX
ring_buf. This prevents data loss by "pausing" incoming data on hardware
level.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
So far all received bytes over UART where blindly drained and pushed to
ring_buf. This approach is okay for UART devices without configured HW
flow control, as it basically decouples data processing from ISR handler
and gives more time before data overrun. However when HW flow control
is enabled, such behavior somehow suppresses UART flow control
advantage, because data can overrun when pushing to ring_buf.
Allow drivers utilizing modem_context framework to pass information
about whether HW flow control is enabled or not. If it is enabled, then
read data from UART FIFO to the point when RX ring_buf is totally filled
and follow such situation by disabling RX interrupt. Incoming data will
be paused on HW level, so there is lots of time for RX thread to process
ring_buf content. Reenable RX interrupts after all data in ring_buf is
processed, so that number of context switches is kept at minimum level.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
This API allows to drop use of preallocated isr_buf. Most importantly as
a result RAM usage is reduced for each driver utilizing modem_context
framework. Additionally there is less copying done in ISR context, as
data is direcly read from UART FIFO to ring_buf.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Now that device_api attribute is unmodified at runtime, as well as all
the other attributes, it is possible to switch all device driver
instance to be constant.
A coccinelle rule is used for this:
@r_const_dev_1
disable optional_qualifier
@
@@
-struct device *
+const struct device *
@r_const_dev_2
disable optional_qualifier
@
@@
-struct device * const
+const struct device *
Fixes#27399
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
The driver utilizes the CONFIG_NET_OFFLOAD setting to avoid the
normal handling of IP packets, and instead uses a socket-like
UART interface to handle incoming and outgoing data via AT commands.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
PR #27485 introduced new implementations for close() that do not build
correctly. This commit fixes the problem by re-implementing them.
Fixes#27587
Signed-off-by: Vincent Wan <vwan@ti.com>
This adds an option to query the modem for the SIM's IMSI and ICCID
numbers, just like the modem's IMEI is queried today. This requires
the SIM to be present, which might not be the case for all
applications, so it can be disabled.
Signed-off-by: Göran Weinholt <goran.weinholt@endian.se>
Signed-off-by: Benjamin Lindqvist <benjamin.lindqvist@endian.se>
Do not route close() calls via ioctl() as that is error prone
and quite pointless. Instead create a callback for close() in
fdtable and use it directly.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
It was already using uart_irq_callback_user_data_set below, now it also
uses uart_irq_callback_user_data_t as callback type, so let's normalize
the callbacks.
Fixes#26923
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Unit tests were failing to build because random header was included by
kernel_includes.h. The problem is that rand32.h includes a generated
file that is either not generated or not included when building unit
tests. Also, it is better to limit the scope of this file to where it is
used.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
By using the Zephyr-native zsock_ family of types and functions, these
drivers will be decoupled from NET_SOCKETS_POSIX_NAMES.
Signed-off-by: Adam Porter <porter.adam@gmail.com>
Used for permission validation when accessing the associated file
descriptors from user mode.
There often get defined in implementation code, expand the search
to look in drivers/ and subsys/net/.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
The implementation of offload_getaddrinfo in this driver failed
when the node it was called with was an IP address. This condition
was never detected, and as a consequence a DNS query was done on
the IP address instead of returning it directly.
Also, the port was set first after running the DNS query.
As a consequence, if the IP address would have been returned directly,
this would have been done without a port been set.
Both errors are fixed in this patch.
Signed-off-by: Hans Wilmers <hans@wilmers.no>
During communication initialisation, the IMSI of the inserted SIM
card is evaluated to determine the APN. This is done by comparing
the first 5 characters of the IMSI to a list of known providers.
The list can be given in Kconfig.
To enable this functionality, set following bool in Kconfig:
MODEM_UBLOX_SARA_AUTODETECT_APN
To set a list of providers, set following string:
MODEM_UBLOX_SARA_AUTODETECT_APN_PROFILES
If the provider can not be found in the list, the APN given in
following entry is used as a fallback:
MODEM_UBLOX_SARA_R4_APN
Signed-off-by: Hans Wilmers <hans@wilmers.no>
The modem type (Sara R410 or Sara U201) is detected automatically after
hardware initialisation of the modem. Further initialisation and
functionality is then chosen depending on the detected modem type.
To enable this functionality, set following bool in Kconfig:
MODEM_UBLOX_SARA_AUTODETECT_VARIANT
Signed-off-by: Hans Wilmers <hans@wilmers.no>
This fixes some cases where an integer timeout received as a parameter
was not converted to a timeout before being used in standard API.
Changes to the POSIX library were not included as that's being
reworked in a separate PR.
Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
TCP contexts are referenced twice,
once for the app and once for the stack.
Since TCP stack is not used for offload,
unref a second time to release the context.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
Following issue is addressed in this bugfix:
When using offloaded sockets with modem ublox_sara_r4,
the socket is only closed if it is in connected state
at the time of the function call. When using UDP sockets,
this leads to a socket never being closed.
Signed-off-by: Hans Wilmers <hans@wilmers.no>
Calculation of RSSI was done incorrectly for Sara U201.
When evaluating +CSQ command responses, the RSSI can be calculated
from the first value, which is <signal_strength>. Instead, the
RSSI was calculated from the second value, which is <qual>.
With the subsequent mapping to RSSI, this results in a wrong
value for RSSI.
This is now corrected by using value <signal_strength> to calculate
the RSSI.
Tested using Sara U201.
Signed-off-by: Hans Wilmers <hans@wilmers.no>
This commit references modem_pin() and modem_shell()
modem_pin(): use new gpio api
The existing pin driver does not respect gpio
configuration in device tree for active high / low
This commit allows for the device tree to determine the
active logic level.
modem_shell(): use correct string length
The ms_send macro uses iface.write() to send a string.
iface.write() requires the length of the string not the
size of the string.
This commit corrects the string length.
drivers: ublox-sara-r4: fix vint polling
This eliminates the implication that the enable and disable values can
be something other than 1 and 0, and fixes the code so it won't enter
an infinite loop if the GPIO read returns an error.
Signed-off-by: Steven Slupsky <sslupsky@gmail.com>
This is needed if muxing is enabled in which case we must
change the UART to muxing UART after the AT+CMUX command
has succeed.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Instead of using physical UART to connection to the modem, use
the GSM 07.10 muxing protocol and UART mux driver to create
virtual channels to the modem. This will allow simultaneous
PPP, AT and other type connections to the modem.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
The net_buf subsystem is now fully compatible with the new timeout
API, so move the selection of the legacy API to those specific
subsystems that use net_buf and still need converting.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Run the int_literal_to_timeout Coccinelle script to fix places where
it is clear that an integer duration is being passed where a timeout
value is required.
Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
By changing the various *NET_DEVICE* macros. It is up to the device
drivers to either set a proper PM function or, if not supported or PM
disabled, to use device_pm_control_nop relevantly.
All existing macro calls are updated. Since no PM support was added so
far, device_pm_control_nop is used as the default everywhere.
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Source and destination ports should be set properly
when assembling the receive socket data.
Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
Some commands need to be processed before a "\r\n" is available and
there might also be commands that have "\r\n" as data but doesn't mean
the end of the command.
To solve this a MODEM_CMD_DIRECT has been added. cmd_handler_process()
will look for matching direct commands before checking if a whole line
is available for matching the normal commands.
A direct command can return either -EAGAIN, meaning that more data is
needed or it will return the number of bytes to skip forward, ie the
length of the command that was handled.
Signed-off-by: Tobias Svehagen <tobias.svehagen@gmail.com>
User is currently able to enable verbose packet debugging for
received packets. This commit enables the same for sent packets.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
pin is an unsigned variable so there is no meaning check if it is less
than zero.
CID :208407
CID :208408
CID :208410
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
usage of AT+UPSD command per UBX-17003787(R15) command reference is:
AT+UPSD=<profile_id>, <param_tag>, <param_val>
For AT+UPSD=0, 1, "<value>": we are setting value to MCCMNO, which
is technically incorrect. <param_tag> of 1 means:
1: APN - <param_val> defines the APN text string, e.g.
"apn.provider.com"; the maximum length is 99. The factory-programmed
value is an empty string.
Let's use APN here instead. This fixes a +CME ERROR: 113 when
connecting with U2 modem.
Fixes: https://github.com/zephyrproject-rtos/zephyr/issues/22689
Signed-off-by: Michael Scott <mike@foundries.io>
Add Kconfig option that allows user to set MCC (Mobile Country
Code). If user does not set it, then automatic operator
registration is used.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Misc fixes / enhancements to the GSM driver:
* set the \r as a line ending character
* make gsm_init() static as there is no need to expose it
* print the gsm context pointer at init
* set buffer allocation timeout to modem context so that it is
not infinite
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Instead of using global static variable "gsm" everywhere,
store the context when calling DEVICE_INIT(). Then in the device
init function get the context from the device struct. This way
it is possible to use the same functions for implementing two
gsm modem instances. Currently this is not fully possible because
the context is not passed via uart_pipe API and modem_cmd
callbacks. So some future work would still be needed.
In practice this commit does not change anything, it just makes
it a little bit easier to have two instance of this modem which
might be quite unlikely case. Anyway, the driver now follows the
same style how some other drivers are done like Ethernet etc.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Now that the u-blox driver can let cmd_handler know that it hasn't
received enough data, let's disable the hex mode for readying
binary data.
On the SARA-R4 this mode limits the receiving MTU to 512 which is
unacceptable.
Signed-off-by: Michael Scott <mike@foundries.io>
Some modem commands can determine if they have enough data pulled from
the modem to continue or not. Let's allow those functions to return
EAGAIN which means there's more data needed from the modem.
Signed-off-by: Michael Scott <mike@foundries.io>
Modem commands are setup with arg_count to denote the number of params
to parse before returning. Let's honor that setting and return once
we've parse them.
This fixes a run-on bug where the parser would find as many of the
parameters via the supplied delimiter as it could.
Signed-off-by: Michael Scott <mike@foundries.io>
The original Ublox SARA-R4 driver was written for the net_context
APIs. As a result many of the return values are not POSIX standard.
Let's go through all of the socket offload functions and make sure
we return standard values (0 or -1) and set errno where appropriate.
Signed-off-by: Michael Scott <mike@foundries.io>
SARA-R4 has a max read limit of 512 when using binary hex formatting.
Otherwise the max read limit is 1024.
Signed-off-by: Michael Scott <mike@foundries.io>
New socket functions were introduced to hide some of the modem_socket
internals:
- modem_socket_next_packet_size()
- modem_socket_wait_data()
- modem_socket_data_ready()
Let's use them.
Signed-off-by: Michael Scott <mike@foundries.io>
Let's use sock->is_connected to check whether we need to clean up
the modem's socket. It may have already been closed via URC.
Signed-off-by: Michael Scott <mike@foundries.io>
SARA-R4 AT command manual states +USOCO has a max timeout of 120s.
Let's use that instead of the default 10s command timeout.
Signed-off-by: Michael Scott <mike@foundries.io>
The SARA R412M requires manual activation of the PDP context. It also
reports RSSI instead of RSRP when on 2G. An off-by-one in the RSRP
calculation was also fixed in this commit.
Signed-off-by: Göran Weinholt <goran.weinholt@endian.se>
The u-blox SARA modems have the ability to output the network status
on a GPIO pin. This can be used to light up a LED when the modem is
connected to the network.
Signed-off-by: Göran Weinholt <goran.weinholt@endian.se>
The U2 modem will sometimes not power off even if we have given it the
signal to do so. We now signal it continually until the modem
indicates that power is off with VINT=0.
Signed-off-by: Göran Weinholt <goran.weinholt@endian.se>
This fixes two problems in modem_reset():
- mdata.net_iface is used without checking that it is valid.
Now, we validate mdata_net_iface before usage, and give a warning
if it was not set.
- if the modem does not perform network registration within the
given time of 20s, in the previous implementation the driver
gave up.
Now, the driver disables RF for a second, enables it again and
gives the modem another 20s to register. This has been seen
to help in roaming situations.
Tested on Sara R4.
Signed-off-by: Hans Wilmers <hans@wilmers.no>
- limit max. number of bytes when sending to socket
The number of bytes sent to a socket in one transaction
is limited to 512 in HEX mode (Sara-R4), and to 1024
otherwise. This corresponds to numbers given in the
manual for ublox cellular modems.
- report number of bytes actually sent, as reported by modem
After writing data to a socket, we now return the number of
bytes actually written, as reported by the modem.
Signed-off-by: Hans Wilmers <hans@wilmers.no>
In order to still process 128 bytes at a time, let's add 1 to the
length of match_buf which will be used to store a NUL char when
the match_buf is at max size (size - 1).
Otherwise we're processing 127 bytes at a time which is inefficient
compared to the data buffer sizes in net_buf.
Signed-off-by: Michael Scott <mike@foundries.io>
SARA-R4 modem supports offloaded DNS via AT+UDNSRN command.
Let's implement it.
NOTE! On SARA-R4 a new firmware *IS* required to support this feature:
L0.0.00.00.05.08 [Apr 17 2019 19:34:02]
Signed-off-by: Michael Scott <mike@foundries.io>
Managing the interface up / down events from driver code (as opposed
to L2 layers) has been an issue for quite some time. There are
race conditions which result in data aborts (referencing NULL
iface or NULL iface->if_dev) or ends up breaking ASSERT checks for
non-NULL iface.
Let's remove the handling for now and come up with something better
when a user actually needs it.
Signed-off-by: Michael Scott <mike@foundries.io>
In offload_recvfrom(), if we end up calling modem_cmd_send(),
then we should always wait for the results. We've already
checked for MSG_DONTWAIT and made sure that there is data ready.
We just need to get it from the modem buffer at this point.
Signed-off-by: Michael Scott <mike@foundries.io>
Users may be waiting for data via socket recv() function. We
notify them that data is ready when URC is received from modem.
Once unblocked, we read the data from the modem buffer which
is handled via on_cmd_sockread_common(). At this point, we
don't need to unblock waiting users again.
Signed-off-by: Michael Scott <mike@foundries.io>
The hex_to_binary() function is incorrectly assuming all buffers
passed to recv() will have an additinal byte for storing a NUL
terminating char. This should be optional as MQTT library uses
exact sized buffers for parsing socket data.
Signed-off-by: Michael Scott <mike@foundries.io>
The send_socket_data() is incorrectly sending 0 as successful result.
The socket APIs require the number of bytes sent to be returned.
Signed-off-by: Michael Scott <mike@foundries.io>
For parsing purposes we need to add a NUL to the end of match_buf.
When there is no CR/LF in the incoming rx bufs then we fill match_buf
to its max size. This ended up with an off by one error which was
overflowing match_buf into the following data.
To account for this, let's fill the buffer to size - 1 so that we
leave room for the NUL at the end and stop corrupting data.
Signed-off-by: Michael Scott <mike@foundries.io>
- rename buf_len to match_len for clarity
- pass in modem_cmd_handler_data instead of buffer pointer directly
- buffer adjustments for the command length are kept inside
parse_params()
Signed-off-by: Michael Scott <mike@foundries.io>
Let's add a field which the drivers can use to keep track of whether
they are connected or not. This will normally be enabled / disabled
in the socket connect and URC for socket close notify.
Signed-off-by: Michael Scott <mike@foundries.io>
Let's hide the internals of sock->packet_sizes[] by adding a function
which returns the size of the next waiting packet.
Signed-off-by: Michael Scott <mike@foundries.io>
Let's hide the internals of the modem_socket's sem_data_ready and
poll handling with 2 new functions:
- modem_socket_wait_data: take a semaphore and wait for data
- modem_socket_data_ready: give back the data ready semaphore and
unblock poll() users
Signed-off-by: Michael Scott <mike@foundries.io>
Add lock behavior for functions in modem_socket, to prevent race
conditions when performing socket data maintenance.
Signed-off-by: Michael Scott <mike@foundries.io>
Let's allow protocols to request portions of the current packet.
This is seen in the MQTT library when parsing headers for the type
and variable length of the packet.
This fixes basic parsing done in the MQTT library and probably others.
Signed-off-by: Michael Scott <mike@foundries.io>
Compile errors because of missing include file and typos
when accessing variables in the modem_pin struct.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
After startup ublox-sara-r4 code sets the MDM_POWER signal to input
using a deprecated configuration macro. This was the only use of the
modem context API to configure a pin.
Refactor the API to not take the flags as an input but instead select
between the flags to be used when the pin is active and a disconnected
state. Use this API instead of a separate direct configure call when
initializing the modem pins.
Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
Conver to the new GPIO API using raw access, since the driver
has its own macros to define signal levels.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Convert to the new API using raw access, since it's a common access
layer shared by multiple (right now only ublox-sara-r4) modems.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Implement uart_pipe functionality for the modem so that it
integrates with the PPP implementation.
Signed-off-by: Patrik Flykt <patrik.flykt@intel.com>
Create a driver for GSM modems that use a standard AT command set
and enable Zephyr's own PPP stack for IP traffic.
Signed-off-by: Patrik Flykt <patrik.flykt@intel.com>
