Re: [PATCH V4 3/4] rpmsg: char: Add TIOCMGET/TIOCMSET ioctl support

Mathieu Poirier
2020-05-19T22:34:01Z

On Wed, May 13, 2020 at 10:41:10AM +0530, Arun Kumar Neelakantam wrote:
> Add TICOMGET and TIOCMSET ioctl support for rpmsg char device nodes

s/TICOMGET/TIOCMGET

> to get/set the low level transport signals.
>
> Signed-off-by: Arun Kumar Neelakantam <aneela@codeaurora.org>
> ---
> drivers/rpmsg/rpmsg_char.c | 53 +++++++++++++++++++++++++++++++++++++++++++---
> 1 file changed, 50 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c
> index 4bbbacd..e2f92f3 100644
> --- a/drivers/rpmsg/rpmsg_char.c
> +++ b/drivers/rpmsg/rpmsg_char.c
> @@ -1,5 +1,6 @@
> // SPDX-License-Identifier: GPL-2.0
> /*
> + * Copyright (c) 2018, The Linux Foundation.
> * Copyright (c) 2016, Linaro Ltd.
> * Copyright (c) 2012, Michal Simek <monstr@monstr.eu>
> * Copyright (c) 2012, PetaLogix
> @@ -19,6 +20,7 @@
> #include <linux/rpmsg.h>
> #include <linux/skbuff.h>
> #include <linux/slab.h>
> +#include <linux/termios.h>
> #include <linux/uaccess.h>
> #include <uapi/linux/rpmsg.h>
>
> @@ -269,15 +271,60 @@ static __poll_t rpmsg_eptdev_poll(struct file *filp, poll_table *wait)
> return mask;
> }
>
> +static int rpmsg_eptdev_tiocmset(struct file *fp, unsigned int cmd,
> + int __user *arg)
> +{
> + struct rpmsg_eptdev *eptdev = fp->private_data;
> + u32 set, clear, val;
> + int ret;
> +
> + ret = get_user(val, arg);
> + if (ret)
> + return ret;
> + set = clear = 0;
> + switch (cmd) {
> + case TIOCMBIS:
> + set = val;
> + break;
> + case TIOCMBIC:
> + clear = val;
> + break;
> + case TIOCMSET:
> + set = val;
> + clear = ~val;
> + break;
> + }
> +
> + set &= TIOCM_DTR | TIOCM_RTS | TIOCM_CD | TIOCM_RI;
> + clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_CD | TIOCM_RI;
> +
> + return rpmsg_set_signals(eptdev->ept, set, clear);
> +}
> +
> static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd,
> unsigned long arg)
> {
> struct rpmsg_eptdev *eptdev = fp->private_data;
> + int ret;
>
> - if (cmd != RPMSG_DESTROY_EPT_IOCTL)
> - return -EINVAL;
> + switch (cmd) {
> + case TIOCMGET:
> + ret = rpmsg_get_signals(eptdev->ept);
> + if (ret >= 0)
> + ret = put_user(ret, (int __user *)arg);
> + break;
> + case TIOCMSET:
> + case TIOCMBIS:
> + case TIOCMBIC:
> + ret = rpmsg_eptdev_tiocmset(fp, cmd, (int __user *)arg);
> + break;
> + case RPMSG_DESTROY_EPT_IOCTL:
> + ret = rpmsg_eptdev_destroy(&eptdev->dev, NULL);
> + default:
> + ret = -EINVAL;
> + }
>
> - return rpmsg_eptdev_destroy(&eptdev->dev, NULL);
> + return ret;
> }
>
> static const struct file_operations rpmsg_eptdev_fops = {
> --
> 2.7.4