On Tue, 2019-06-11 at 10:52 -0600, Subash Abhinov Kasiviswanathan wrote: > > The general plan (and I believe Daniele Palmas was working on it) > > was > > to eventually make qmi_wwan use rmnet rather than its internal > > sysfs- > > based implementation. qmi_wwan and ipa are at essentially the same > > level and both could utilize rmnet on top. > > > > *That's* what I'd like to see. I don't want to see two different > > ways > > to get QMAP packets to modem firmware from two different drivers > > that > > really could use the same code. > > > > Dan > > qmi_wwan is based on USB and is very different from the IPA > interconnect > though. AFAIK, they do not have much in common (apart from sending & > receiving MAP packets from hardware). That is correct, they are very different drivers but as you state they send and receive MAP packets with the other end via some closer-to- hardware protocol (USB or GSI?) than QMAP. rmnet should handle muxing the QMAP, QoS, and aggregation and pass the resulting packet to the lower layer. That lower layer could be IPA or qmi_wwan, which in turn passes that QMAP packet to USB or GSI or whatever. This is typically how Linux handles clean abstractions between different protocol layers in drivers. Similar to some WiFi drivers (drivers/net/wireless/marvell/libertas for example) where the same firmware interface can be accessed via PCI, SDIO, USB, SPI, etc. The bus-specific code is self-contained and does not creep into the upper more generic parts. Dan
