Re: [PATCH v1 4/4] mhi_bus: dev: uci: add user space interface driver

[Arnd Bergmann <arnd@arndb.de>]

On Fri, Apr 27, 2018 at 4:23 AM, Sujeev Dias <sdias@codeaurora.org> wrote:
> This module allows user space clients to transfer data
> between external modem and host using standard file
> operations.
>
> Signed-off-by: Sujeev Dias <sdias@codeaurora.org>
> ---
>  drivers/bus/mhi/devices/Kconfig   |   9 +
>  drivers/bus/mhi/devices/Makefile  |   1 +
>  drivers/bus/mhi/devices/mhi_uci.c | 662 ++++++++++++++++++++++++++++++++++++++
>  3 files changed, 672 insertions(+)
>  create mode 100644 drivers/bus/mhi/devices/mhi_uci.c
>
> diff --git a/drivers/bus/mhi/devices/Kconfig b/drivers/bus/mhi/devices/Kconfig
> index 40f964d..83b9673 100644
> --- a/drivers/bus/mhi/devices/Kconfig
> +++ b/drivers/bus/mhi/devices/Kconfig
> @@ -7,4 +7,13 @@ config MHI_NETDEV
>           MHI based net device driver for transferring IP traffic
>           between host and modem. By enabling this driver, clients
>           can transfer data using standard network interface.
> +
> +config MHI_UCI
> +       tristate "MHI UCI"
> +       depends on MHI_BUS
> +       help
> +         MHI based uci driver is for transferring data between host and
> +         modem using standard file operations from user space. Open, read,
> +         write, ioctl, and close operations are supported by this driver.
> +

Can you expand this description both in Kconfig and the patch
changelog? It's not clear at all what this is good for and what the
actual data is that you send over it.

What tools do you use to talk to them, can you point to a source
repository here? I think that would be useful in order to decide
whether we actually need a low-level interface at all, or if it
should all be accessed using high-level interfaces like the
network driver.

       Arnd