[PATCH V5 3/4] rpmsg: char: Add TIOCMGET/TIOCMSET ioctl support

From: Deepak Kumar Singh
Date: Wed Jun 24 2020 - 13:45:39 EST


From: Arun Kumar Neelakantam <aneela@xxxxxxxxxxxxxx>

Add TICOMGET and TIOCMSET ioctl support for rpmsg char device nodes
to get/set the low level transport signals.

Signed-off-by: Deepak Kumar Singh <deesin@xxxxxxxxxxxxxx>
Signed-off-by: Arun Kumar Neelakantam <aneela@xxxxxxxxxxxxxx>
---
drivers/rpmsg/rpmsg_char.c | 54 +++++++++++++++++++++++++++++++++++++++++++---
1 file changed, 51 insertions(+), 3 deletions(-)

diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c
index 4bbbacd..43ceac0 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@xxxxxxxxx>
* 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 +271,61 @@ 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);
+ break;
+ default:
+ ret = -EINVAL;
+ }

- return rpmsg_eptdev_destroy(&eptdev->dev, NULL);
+ return ret;
}

static const struct file_operations rpmsg_eptdev_fops = {
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project