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From:   Loic Poulain <loic.poulain@linaro.org>
Date:   Fri, 28 Oct 2022 12:35:01 +0200
Message-ID: <CAMZdPi-tz4_vxum8SYbYVuv71UYhe4QUGO6_w8TPFBcw9oydfQ@mail.gmail.com>
Subject: Re: [PATCH net-next] net: wwan: iosm: add rpc interface for xmm modems
To:     Shane Parslow <shaneparslow808@gmail.com>
Cc:     m.chetan.kumar@intel.com, linuxwwan@intel.com,
        Sergey Ryazanov <ryazanov.s.a@gmail.com>,
        Johannes Berg <johannes@sipsolutions.net>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
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On Fri, 28 Oct 2022 at 02:37, Shane Parslow <shaneparslow808@gmail.com> wrote:
>
> Add a new iosm wwan port that connects to the modem rpc interface. This
> interface provides a configuration channel, and in the case of the 7360, is
> the only way to configure the modem (as it does not support mbim).

Doesn't the AT channel offer that possibility? what is the status of
7360 support without this change?

> The new interface is compatible with existing software, such as
> open_xdatachannel.py from the xmm7360-pci project [1].
>
> [1] https://github.com/xmm7360/xmm7360-pci
>
> Signed-off-by: Shane Parslow <shaneparslow808@gmail.com>
> ---
>  drivers/net/wwan/iosm/iosm_ipc_chnl_cfg.c | 2 +-
>  drivers/net/wwan/wwan_core.c              | 4 ++++
>  include/linux/wwan.h                      | 2 ++
>  3 files changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/wwan/iosm/iosm_ipc_chnl_cfg.c b/drivers/net/wwan/iosm/iosm_ipc_chnl_cfg.c
> index 128c999e08bb..91e3e83fc47b 100644
> --- a/drivers/net/wwan/iosm/iosm_ipc_chnl_cfg.c
> +++ b/drivers/net/wwan/iosm/iosm_ipc_chnl_cfg.c
> @@ -39,7 +39,7 @@ static struct ipc_chnl_cfg modem_cfg[] = {
>         /* RPC - 0 */
>         { IPC_MEM_CTRL_CHL_ID_1, IPC_MEM_PIPE_2, IPC_MEM_PIPE_3,
>           IPC_MEM_MAX_TDS_RPC, IPC_MEM_MAX_TDS_RPC,
> -         IPC_MEM_MAX_DL_RPC_BUF_SIZE, WWAN_PORT_UNKNOWN },
> +         IPC_MEM_MAX_DL_RPC_BUF_SIZE, WWAN_PORT_RPC },
>         /* IAT0 */
>         { IPC_MEM_CTRL_CHL_ID_2, IPC_MEM_PIPE_4, IPC_MEM_PIPE_5,
>           IPC_MEM_MAX_TDS_AT, IPC_MEM_MAX_TDS_AT, IPC_MEM_MAX_DL_AT_BUF_SIZE,
> diff --git a/drivers/net/wwan/wwan_core.c b/drivers/net/wwan/wwan_core.c
> index 62e9f7d6c9fe..cf16a2704914 100644
> --- a/drivers/net/wwan/wwan_core.c
> +++ b/drivers/net/wwan/wwan_core.c
> @@ -319,6 +319,10 @@ static const struct {
>                 .name = "FIREHOSE",
>                 .devsuf = "firehose",
>         },
> +       [WWAN_PORT_RPC] = {
> +               .name = "RPC",
> +               .devsuf = "rpc",
> +       },

RPC sounds more like a generic method than an actual XMM-specific
protocol, isn't there a more precise name for that protocol? if not,
maybe XMMRPC is more appropriate?

>  };
>
>  static ssize_t type_show(struct device *dev, struct device_attribute *attr,
> diff --git a/include/linux/wwan.h b/include/linux/wwan.h
> index 5ce2acf444fb..3cf2182ad4e9 100644
> --- a/include/linux/wwan.h
> +++ b/include/linux/wwan.h
> @@ -15,6 +15,7 @@
>   * @WWAN_PORT_QMI: Qcom modem/MSM interface for modem control
>   * @WWAN_PORT_QCDM: Qcom Modem diagnostic interface
>   * @WWAN_PORT_FIREHOSE: XML based command protocol
> + * @WWAN_PORT_RPC: Control protocol for Intel XMM modems
>   *
>   * @WWAN_PORT_MAX: Highest supported port types
>   * @WWAN_PORT_UNKNOWN: Special value to indicate an unknown port type
> @@ -26,6 +27,7 @@ enum wwan_port_type {
>         WWAN_PORT_QMI,
>         WWAN_PORT_QCDM,
>         WWAN_PORT_FIREHOSE,
> +       WWAN_PORT_RPC,
>
>         /* Add new port types above this line */
>
> --
> 2.38.1
>

Reagrds,
Loic