Commit 5550201c authored by Chris Lew's avatar Chris Lew Committed by Bjorn Andersson
Browse files

rpmsg: char: Add RPMSG GET/SET FLOWCONTROL IOCTL support 



Add RPMSG_GET_OUTGOING_FLOWCONTROL and RPMSG_SET_INCOMING_FLOWCONTROL
IOCTL support for rpmsg char device nodes to get/set the low level
transport signals.

Signed-off-by: default avatarChris Lew <quic_clew@quicinc.com>
Signed-off-by: default avatarDeepak Kumar Singh <quic_deesin@quicinc.com>
Signed-off-by: default avatarSarannya S <quic_sarannya@quicinc.com>
Acked-by: default avatarArnaud Pouliquen <arnaud.pouliquen@foss.st.com>
Link: https://lore.kernel.org/r/1688679698-31274-4-git-send-email-quic_sarannya@quicinc.com


Signed-off-by: default avatarBjorn Andersson <andersson@kernel.org>
parent a2b73aa5

drivers/rpmsg/rpmsg_char.c

+48 −6
Original line number Diff line number Diff line
@@ -52,6 +52,8 @@ static DEFINE_IDA(rpmsg_minor_ida); 
 * @readq:	wait object for incoming queue

 * @default_ept: set to channel default endpoint if the default endpoint should be re-used

 *              on device open to prevent endpoint address update.

 * remote_flow_restricted: to indicate if the remote has requested for flow to be limited

 * remote_flow_updated: to indicate if the flow control has been requested

 */

struct rpmsg_eptdev {

	struct device dev;
@@ -68,6 +70,8 @@ struct rpmsg_eptdev { 
	struct sk_buff_head queue;

	wait_queue_head_t readq;



	bool remote_flow_restricted;

	bool remote_flow_updated;

};



int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data)
@@ -116,6 +120,18 @@ static int rpmsg_ept_cb(struct rpmsg_device *rpdev, void *buf, int len, 
	return 0;

}



static int rpmsg_ept_flow_cb(struct rpmsg_device *rpdev, void *priv, bool enable)

{

	struct rpmsg_eptdev *eptdev = priv;



	eptdev->remote_flow_restricted = enable;

	eptdev->remote_flow_updated = true;



	wake_up_interruptible(&eptdev->readq);



	return 0;

}



static int rpmsg_eptdev_open(struct inode *inode, struct file *filp)

{

	struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev);
@@ -152,6 +168,7 @@ static int rpmsg_eptdev_open(struct inode *inode, struct file *filp) 
		return -EINVAL;

	}



	ept->flow_cb = rpmsg_ept_flow_cb;

	eptdev->ept = ept;

	filp->private_data = eptdev;

	mutex_unlock(&eptdev->ept_lock);
@@ -172,6 +189,7 @@ static int rpmsg_eptdev_release(struct inode *inode, struct file *filp) 
		eptdev->ept = NULL;

	}

	mutex_unlock(&eptdev->ept_lock);

	eptdev->remote_flow_updated = false;



	/* Discard all SKBs */

	skb_queue_purge(&eptdev->queue);
@@ -285,6 +303,9 @@ static __poll_t rpmsg_eptdev_poll(struct file *filp, poll_table *wait) 
	if (!skb_queue_empty(&eptdev->queue))

		mask |= EPOLLIN | EPOLLRDNORM;



	if (eptdev->remote_flow_updated)

		mask |= EPOLLPRI;



	mutex_lock(&eptdev->ept_lock);

	mask |= rpmsg_poll(eptdev->ept, filp, wait);

	mutex_unlock(&eptdev->ept_lock);
@@ -297,14 +318,35 @@ static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd, 
{

	struct rpmsg_eptdev *eptdev = fp->private_data;



	if (cmd != RPMSG_DESTROY_EPT_IOCTL)

		return -EINVAL;

	bool set;

	int ret;



	switch (cmd) {

	case RPMSG_GET_OUTGOING_FLOWCONTROL:

		eptdev->remote_flow_updated = false;

		ret = put_user(eptdev->remote_flow_restricted, (int __user *)arg);

		break;

	case RPMSG_SET_INCOMING_FLOWCONTROL:

		if (arg > 1) {

			ret = -EINVAL;

			break;

		}

		set = !!arg;

		ret = rpmsg_set_flow_control(eptdev->ept, set, eptdev->chinfo.dst);

		break;

	case RPMSG_DESTROY_EPT_IOCTL:

		/* Don't allow to destroy a default endpoint. */

	if (eptdev->default_ept)

		return -EINVAL;

		if (eptdev->default_ept) {

			ret = -EINVAL;

			break;

		}

		ret = rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL);

		break;

	default:

		ret = -EINVAL;

	}



	return rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL);

	return ret;

}



static const struct file_operations rpmsg_eptdev_fops = {

include/uapi/linux/rpmsg.h

+10 −0
Original line number Diff line number Diff line
@@ -43,4 +43,14 @@ struct rpmsg_endpoint_info { 
 */

#define RPMSG_RELEASE_DEV_IOCTL	_IOW(0xb5, 0x4, struct rpmsg_endpoint_info)



/**

 * Get the flow control state of the remote rpmsg char device.

 */

#define RPMSG_GET_OUTGOING_FLOWCONTROL _IOR(0xb5, 0x5, int)



/**

 * Set the flow control state of the local rpmsg char device.

 */

#define RPMSG_SET_INCOMING_FLOWCONTROL _IOR(0xb5, 0x6, int)



#endif