Re: [PATCH 0/3] Add MHI Endpoint network driver

[Jeffrey Hugo]

On 6/7/2023 1:41 AM, Manivannan Sadhasivam wrote:
> On Wed, Jun 07, 2023 at 09:12:00AM +0200, Loic Poulain wrote:
> > On Wed, 7 Jun 2023 at 08:56, Manivannan Sadhasivam
> > <manivannan.sadhasivam@xxxxxxxxxx> wrote:
> > > On Tue, Jun 06, 2023 at 02:59:00PM +0200, Andrew Lunn wrote:
> > > > On Tue, Jun 06, 2023 at 06:01:16PM +0530, Manivannan Sadhasivam wrote:
> > > > > Hi,
> > > > >
> > > > > This series adds a network driver for the Modem Host Interface (MHI) endpoint
> > > > > devices that provides network interfaces to the PCIe based Qualcomm endpoint
> > > > > devices supporting MHI bus (like Modems). This driver allows the MHI endpoint
> > > > > devices to establish IP communication with the host machines (x86, ARM64) over
> > > > > MHI bus.
> > > > >
> > > > > On the host side, the existing mhi_net driver provides the network connectivity
> > > > > to the host.
> > > > >
> > > > > - Mani
> > > > >
> > > > > Manivannan Sadhasivam (3):
> > > > >    net: Add MHI Endpoint network driver
> > > > >    MAINTAINERS: Add entry for MHI networking drivers under MHI bus
> > > > >    net: mhi: Increase the default MTU from 16K to 32K
> > > > >
> > > > >   MAINTAINERS              |   1 +
> > > > >   drivers/net/Kconfig      |   9 ++
> > > > >   drivers/net/Makefile     |   1 +
> > > > >   drivers/net/mhi_ep_net.c | 331 +++++++++++++++++++++++++++++++++++++++
> > > > >   drivers/net/mhi_net.c    |   2 +-
> > > >
> > > > Should we add a drivers/net/modem directory? Maybe modem is too
> > > > generic, we want something which represents GSM, LTE, UMTS, 3G, 4G,
> > > > 5G, ... XG etc.
> > >
> > > The generic modem hierarchy sounds good to me because most of the times a
> > > single driver handles multiple technologies. The existing drivers supporting
> > > modems are already under different hierarchy like usb, wwan etc... So unifying
> > > them makes sense. But someone from networking community should take a call.
> >
> >
> > Yes, so there is already a drivers/net/wwan directory for this, in
> > which there are drivers for control and data path, that together
> > represent a given 'wwan' (modem) entity. So the generic mhi_net could
> > be moved there, but the point is AFAIU, that MHI, despite his name, is
> > not (more) used only for modem, but as a generic memory sharing based
> > transport protocol, such as virtio. It would then not be necessarily
> > true that a peripheral exposing MHI net channel is actually a modem?
>
> Agree, mhi_*_net drivers can be used by non-modem devices too as long as they
> support MHI protocol.

I know of at-least 1 non-modem product in development that would benefit 
from these drivers.