1 files changed, 110 insertions, 0 deletions
diff --git a/drivers/rpmsg/imx_rpmsg_pingpong.c b/drivers/rpmsg/imx_rpmsg_pingpong.c
new file mode 100644
index 000000000000..a6843b360e80
--- /dev/null
+++ b/drivers/rpmsg/imx_rpmsg_pingpong.c
@@ -0,0 +1,110 @@
+/*
+ * Copyright (C) 2015 Freescale Semiconductor, Inc.
+ *
+ * derived from the omap-rpmsg implementation.
+ * Remote processor messaging transport - pingpong driver
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/virtio.h>
+#include <linux/rpmsg.h>
+
+#define MSG		"hello world!"
+#define MSG_LIMIT	1000
+static unsigned int rpmsg_pingpong;
+static int rx_count;
+
+static void rpmsg_pingpong_cb(struct rpmsg_channel *rpdev, void *data, int len,
+						void *priv, u32 src)
+{
+	int err;
+
+	/* reply */
+	rpmsg_pingpong = *(unsigned int *)data;
+	pr_info("get %d (src: 0x%x)\n",
+			rpmsg_pingpong, src);
+	rx_count++;
+
+	/* pingpongs should not live forever */
+	if (rx_count >= MSG_LIMIT) {
+		dev_info(&rpdev->dev, "goodbye!\n");
+		return;
+	}
+	rpmsg_pingpong++;
+	err = rpmsg_sendto(rpdev, (void *)(&rpmsg_pingpong), 4, src);
+
+	if (err)
+		dev_err(&rpdev->dev, "rpmsg_send failed: %d\n", err);
+}
+
+static int rpmsg_pingpong_probe(struct rpmsg_channel *rpdev)
+{
+	int err;
+
+	dev_info(&rpdev->dev, "new channel: 0x%x -> 0x%x!\n",
+			rpdev->src, rpdev->dst);
+
+	/*
+	 * send a message to our remote processor, and tell remote
+	 * processor about this channel
+	 */
+	err = rpmsg_send(rpdev, MSG, strlen(MSG));
+	if (err) {
+		dev_err(&rpdev->dev, "rpmsg_send failed: %d\n", err);
+		return err;
+	}
+
+	rpmsg_pingpong = 0;
+	rx_count = 0;
+	err = rpmsg_sendto(rpdev, (void *)(&rpmsg_pingpong), 4, rpdev->dst);
+	if (err) {
+		dev_err(&rpdev->dev, "rpmsg_send failed: %d\n", err);
+		return err;
+	}
+
+	return 0;
+}
+
+static void rpmsg_pingpong_remove(struct rpmsg_channel *rpdev)
+{
+	dev_info(&rpdev->dev, "rpmsg pingpong driver is removed\n");
+}
+
+static struct rpmsg_device_id rpmsg_driver_pingpong_id_table[] = {
+	{ .name	= "rpmsg-openamp-demo-channel" },
+	{ },
+};
+MODULE_DEVICE_TABLE(rpmsg, rpmsg_driver_pingpong_id_table);
+
+static struct rpmsg_driver rpmsg_pingpong_driver = {
+	.drv.name	= KBUILD_MODNAME,
+	.drv.owner	= THIS_MODULE,
+	.id_table	= rpmsg_driver_pingpong_id_table,
+	.probe		= rpmsg_pingpong_probe,
+	.callback	= rpmsg_pingpong_cb,
+	.remove		= rpmsg_pingpong_remove,
+};
+
+static int __init init(void)
+{
+	return register_rpmsg_driver(&rpmsg_pingpong_driver);
+}
+
+static void __exit fini(void)
+{
+	unregister_rpmsg_driver(&rpmsg_pingpong_driver);
+}
+module_init(init);
+module_exit(fini);
+
+MODULE_AUTHOR("Freescale Semiconductor, Inc.");
+MODULE_DESCRIPTION("iMX virtio remote processor messaging pingpong driver");
+MODULE_LICENSE("GPL v2");