VintageNetQMI

This library provides a VintageNet technology for cellular modems that support the Qualcomm MSM Interface. This includes most USB cellular modems. See VintageNetMobile if you have a modem that only supports an AT command interface.

To use this library, first add it to your project's dependency list:

def deps do
  [
    {:vintage_net_qmi, "~> 0.3.2"}
  ]
end

You will then need to configure VintageNet. The easiest way to configure a modem at runtime is by calling VintageNetQMI.quick_configure("the_apn"). For example:

iex> VintageNetQMI.quick_configure("the_apn")
:ok
# wait...
iex> VintageNet.info
Interface wwan0
  Type: VintageNetQMI
  Power: On (watchdog timeout in 51628 ms)
  Present: true
  State: :configured (0:41:09)
  Connection: :internet (0:40:28)
  Addresses: 100.79.205.206/30, fe80::723c:bdc9:10e4:d092/64
  Configuration:
    %{
      type: VintageNetQMI,
      vintage_net_qmi: %{service_providers: [%{apn: "the_apn"}]}
    }

You can't always call quick_configure/1 convenience function so here's the regular configuration. If you are moving code from vintage_net_mobile, you'll notice that this format is very similar except that Mobile is now QMI.

VintageNet.configure("wwan0", %{
      type: VintageNetQMI,
      vintage_net_qmi: %{
        service_providers: [%{apn: "the_apn"}]
      }
    })

The :service_providers key should be set to information provided by each of your service providers. It is common that this is a list of one item. Currently only one service provider is supported, so replace "fill_in" with the APN that they gave you.

Service provider APN selection via ICCID

If you're deploying SIMs from multiple service providers, you'll need to set the APN based on what SIM was installed in the device. One way is to set a configuration manually when you install the SIM. An easier way is to have VintageNetQMI pick the APN based on the SIM's ICCID.

This featured is enabled by using the :only_iccid_prefixes option and listing multiple service providers. VintageNetQMI looks at the :service_providers list in order until one matches. Leave off the:only_iccid_prefixes option on the final service provider to provide a catch-all APN.

Here's an example:

VintageNet.configure("wwan0", %{
      type: VintageNetQMI,
      vintage_net_qmi: %{
        service_providers: [
          %{apn: "special_service_provider", only_iccid_prefixes: ["8973611", "8973612"]},
          %{apn: "default_apn"}
        ]
      }
    })

Configure radio technologies

In some cases you might want to set to the radio access technology (RAT) to only use a subset of what the modem is capable of using. To specify which RATs to use you can set the optional configuration field :only_radio_technologies.

VintageNet.configure("wwan0", %{
      type: VintageNetQMI,
      vintage_net_qmi: %{
        only_radio_technologies: [:lte, :umts],
        service_providers: [
          %{apn: "apn_name"}
        ]
      }
    })

The example above will limit the possible RATs used to :lte (4G) and :umts (3G). For more information which radio technologies are available please see the :qmi documentation.

If this configuration is provided, the modem will use the default configuration that provided by the manufacturer.

Configure roaming

Support for allowing roaming is set on a per-service provider basis using the :roaming_allowed? key. In QMI, this field is optional and if unset here, VintageNetQMI will not send any preference to the modem. The following example shows a configuration where roaming is allowed:

VintageNet.configure("wwan0", %{
      type: VintageNetQMI,
      vintage_net_qmi: %{
        only_radio_technologies: [:lte, :umts],
        service_providers: [
          %{apn: "apn_name", roaming_allowed?: true}
        ]
      }
    })

VintageNet Properties

In addition to the common vintage_net properties for all interface types, this technology the following:

The following properties are TBD:

Transmit and receive statistics

The statistics value is a map with the fields:

• :timestamp - the monotonic time for when these stats where last updated
• :tx_bytes - total bytes transmitted
• :rx_bytes - total bytes received
• :tx_packets - total packets transmitted without error
• :rx_packets - total packets received without error
• :tx_errors - total outgoing packets with framing errors
• :rx_errors - total incoming packets with framing errors
• :tx_overflows - total outing packets dropped due to buffer overflows
• :rx_overflows - total incoming packets dropped due to buffer overflows
• :tx_drops - total outgoing packets dropped
• :rx_drops - total incoming packets dropped

Types of radio access technologies

• :amps - Advanced Mobile Phone System (legacy)
• :gsm - Global System for Mobile Communication (3G & 2G)
• :umts - Universal Mobile Telecommunications System (3G)
• :lte - Long-Term Evolution (4G)
• :cdma_1x - CDMA2000 1X (3G & 2G)
• :cdma_1x_evdo - CDMA2000 1xEV-DO (3G & 2G)

If you migrating from VintageNetMobile you will need to update any code that uses this property to handle the above list of atoms.

System requirements

These requirements are believed to be the minimum needed to be added to the official Nerves systems.

Linux kernel

Enable QMI and drivers for your modem:

CONFIG_USB_USBNET=m
CONFIG_USB_NET_CDC_NCM=m
CONFIG_USB_NET_QMI_WWAN=m
CONFIG_USB_SERIAL_OPTION=m

If you're using a Huawei modem, you might also want:

CONFIG_USB_NET_HUAWEI_CDC_NCM=m