[PATCH 2/4] rpmsg: ctrl: Introduce RPMSG_RELEASE_DEV_IOCTL

[Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>]

Implement the RPMSG_RELEASE_DEV_IOCTL to allow the user application to
release a rpmsg device created either by the remote processor or with
the RPMSG_CREATE_DEV_IOCTL call.
Depending on the back-end implementation, the associated rpmsg driver is
removed and a NS destroy rpmsg can be sent to the remote processor.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
---
 drivers/rpmsg/rpmsg_ctrl.c | 7 +++++++
 include/uapi/linux/rpmsg.h | 5 +++++
 2 files changed, 12 insertions(+)

diff --git a/drivers/rpmsg/rpmsg_ctrl.c b/drivers/rpmsg/rpmsg_ctrl.c
index 4aa962df3661..cb19e32d05e1 100644
--- a/drivers/rpmsg/rpmsg_ctrl.c
+++ b/drivers/rpmsg/rpmsg_ctrl.c
@@ -98,6 +98,13 @@ static long rpmsg_ctrldev_ioctl(struct file *fp, unsigned int cmd,
 		}
 		break;
 
+	case RPMSG_RELEASE_DEV_IOCTL:
+		ret = rpmsg_release_channel(ctrldev->rpdev, &chinfo);
+		if (ret)
+			dev_err(&ctrldev->dev, "failed to release %s channel (%d)\n",
+				chinfo.name, ret);
+		break;
+
 	default:
 		ret = -EINVAL;
 	}
diff --git a/include/uapi/linux/rpmsg.h b/include/uapi/linux/rpmsg.h
index f9d5a74e7801..38639ba37438 100644
--- a/include/uapi/linux/rpmsg.h
+++ b/include/uapi/linux/rpmsg.h
@@ -38,4 +38,9 @@ struct rpmsg_endpoint_info {
  */
 #define RPMSG_CREATE_DEV_IOCTL	_IOW(0xb5, 0x3, struct rpmsg_endpoint_info)
 
+/**
+ * Release a local rpmsg device.
+ */
+#define RPMSG_RELEASE_DEV_IOCTL	_IOW(0xb5, 0x4, struct rpmsg_endpoint_info)
+
 #endif
-- 
2.17.1