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Message-ID: <1dff1b277e5d2c95ce100a2daff4967f98d074ba.camel@perches.com>
Subject: Re: [PATCH v7 2/2] tty: add rpmsg driver
From:   Joe Perches <joe@perches.com>
To:     Arnaud Pouliquen <arnaud.pouliquen@st.com>,
        Ohad Ben-Cohen <ohad@wizery.com>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jslaby@suse.com>, linux-kernel@vger.kernel.org,
        linux-remoteproc@vger.kernel.org,
        Mathieu Poirier <mathieu.poirier@linaro.org>
Cc:     Suman Anna <s-anna@ti.com>,
        Fabien DESSENNE <fabien.dessenne@st.com>,
        linux-stm32@st-md-mailman.stormreply.com,
        Alan Cox <gnomes@lxorguk.ukuu.org.uk>,
        xiang xiao <xiaoxiang781216@gmail.com>
Date:   Tue, 24 Mar 2020 10:23:05 -0700
In-Reply-To: <20200324170407.16470-3-arnaud.pouliquen@st.com>
References: <20200324170407.16470-1-arnaud.pouliquen@st.com>
         <20200324170407.16470-3-arnaud.pouliquen@st.com>
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On Tue, 2020-03-24 at 18:04 +0100, Arnaud Pouliquen wrote:
> This driver exposes a standard TTY interface on top of the rpmsg
> framework through a rpmsg service.
> 
> This driver supports multi-instances, offering a /dev/ttyRPMSGx entry
> per rpmsg endpoint.

trivial notes:

> diff --git a/Documentation/serial/tty_rpmsg.rst b/Documentation/serial/tty_rpmsg.rst
[]
> +The rpmsg tty driver implements serial communication on the RPMsg bus to makes possible for user-space programs to send and receive rpmsg messages as a standard tty protocol.

Very long text lines missing newlines?

[]
> +To be compliant with this driver, the remote firmware must create its data end point associated with the "rpmsg-tty-raw" service.
[]
> +To be compatible with this driver, the remote firmware must create or use its end point associated with "rpmsg-tty-ctrl" service, plus a second endpoint for the data flow.
> +On Linux rpmsg_tty probes, the data endpoint address and the CTS (set to disable)

[]

> diff --git a/drivers/tty/rpmsg_tty.c b/drivers/tty/rpmsg_tty.c
[]
> +typedef void (*rpmsg_tty_rx_cb_t)(struct rpmsg_device *, void *, int, void *,
> +				  u32);

unused typedef?

[]

> +static int __init rpmsg_tty_init(void)
> +{
[]
> +	err = tty_register_driver(rpmsg_tty_driver);
> +	if (err < 0) {
> +		pr_err("Couldn't install rpmsg tty driver: err %d\n", err);
> +		goto error_put;
> +	}

Might use vsprintf extension %pe

		pr_err("Couldn't install rpmsg tty driver: %pe\n", ERR_PTR(err));

> +	err = register_rpmsg_driver(&rpmsg_tty_rpmsg_drv);
> +	if (err < 0) {
> +		pr_err("Couldn't register rpmsg tty driver: err %d\n", err);

etc.