diff mbox series

[V2,4/4] rpmsg: char: Add signal callback and POLLPRI support

Message ID 1538660420-27797-5-git-send-email-aneela@codeaurora.org (mailing list archive)
State New, archived
Headers show
Series Add TIOCM Signals support for RPMSG char devices | expand

Commit Message

Arun Kumar Neelakantam Oct. 4, 2018, 1:40 p.m. UTC 
Register a callback to get the signal notifications from rpmsg and
send POLLPRI mask to indicate the signal change in POLL system call.

Signed-off-by: Arun Kumar Neelakantam <aneela@codeaurora.org>
---
 drivers/rpmsg/rpmsg_char.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)
diff mbox series

Patch

diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c
index 9380c6e..194d54a 100644
--- a/drivers/rpmsg/rpmsg_char.c
+++ b/drivers/rpmsg/rpmsg_char.c
@@ -64,6 +64,7 @@  struct rpmsg_ctrldev {
  * @queue_lock:	synchronization of @queue operations
  * @queue:	incoming message queue
  * @readq:	wait object for incoming queue
+ * @sig_pending:state of signal notification
  */
 struct rpmsg_eptdev {
 	struct device dev;
@@ -78,6 +79,8 @@  struct rpmsg_eptdev {
 	spinlock_t queue_lock;
 	struct sk_buff_head queue;
 	wait_queue_head_t readq;
+
+	bool sig_pending;
 };
 
 static int rpmsg_eptdev_destroy(struct device *dev, void *data)
@@ -122,6 +125,18 @@  static int rpmsg_ept_cb(struct rpmsg_device *rpdev, void *buf, int len,
 	return 0;
 }
 
+static int rpmsg_sigs_cb(struct rpmsg_device *rpdev, void *priv,
+			 u32 old, u32 new)
+{
+	struct rpmsg_eptdev *eptdev = priv;
+
+	eptdev->sig_pending = true;
+
+	/* wake up any blocking processes, waiting for signal notification */
+	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);
@@ -138,6 +153,7 @@  static int rpmsg_eptdev_open(struct inode *inode, struct file *filp)
 		return -EINVAL;
 	}
 
+	ept->sig_cb = rpmsg_sigs_cb;
 	eptdev->ept = ept;
 	filp->private_data = eptdev;
 
@@ -157,6 +173,7 @@  static int rpmsg_eptdev_release(struct inode *inode, struct file *filp)
 		eptdev->ept = NULL;
 	}
 	mutex_unlock(&eptdev->ept_lock);
+	eptdev->sig_pending = false;
 
 	/* Discard all SKBs */
 	while (!skb_queue_empty(&eptdev->queue)) {
@@ -263,6 +280,9 @@  static __poll_t rpmsg_eptdev_poll(struct file *filp, poll_table *wait)
 	if (!skb_queue_empty(&eptdev->queue))
 		mask |= EPOLLIN | EPOLLRDNORM;
 
+	if (eptdev->sig_pending)
+		mask |= POLLPRI;
+
 	mask |= rpmsg_poll(eptdev->ept, filp, wait);
 
 	return mask;
@@ -307,6 +327,7 @@  static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd,
 
 	switch (cmd) {
 	case TIOCMGET:
+		eptdev->sig_pending = false;
 		ret = rpmsg_get_signals(eptdev->ept, &lsigs, &rsigs);
 		if (!ret)
 			ret = put_user(rsigs, (int __user *)arg);