[RFC PATCH 05/10] rpmsg: add sample client driver

[Tanmay Shah]

Add driver to demonstrate use of rpmsg framework.

Signed-off-by: Tanmay Shah <tanmay.shah at amd.com>
---
 drivers/rpmsg/Kconfig               |  8 ++++
 drivers/rpmsg/Makefile              |  3 ++
 drivers/rpmsg/rpmsg_sample_client.c | 63 +++++++++++++++++++++++++++++
 3 files changed, 74 insertions(+)
 create mode 100644 drivers/rpmsg/rpmsg_sample_client.c

diff --git a/drivers/rpmsg/Kconfig b/drivers/rpmsg/Kconfig
index 4efb8dfcd7..808cd16275 100644
--- a/drivers/rpmsg/Kconfig
+++ b/drivers/rpmsg/Kconfig
@@ -28,4 +28,12 @@ config RPMSG_SANDBOX
 	  Say 'y' here to add sandbox driver for RPMsg framework used
 	  for dummy communication with remote processor on sandbox platform
 
+config RPMSG_SAMPLE_CLIENT
+	bool "Sample RPMsg client driver"
+	depends on DM
+	select RPMSG
+	help
+	  Say 'y' here to enable driver that demonstrate use of RPMsg framework.
+	  This driver uses RPMsg APIs to communicate with remote processor.
+
 endmenu
diff --git a/drivers/rpmsg/Makefile b/drivers/rpmsg/Makefile
index 21611725ea..53af0f7ea6 100644
--- a/drivers/rpmsg/Makefile
+++ b/drivers/rpmsg/Makefile
@@ -6,5 +6,8 @@ obj-$(CONFIG_RPMSG) += rpmsg-uclass.o
 
 obj-$(CONFIG_RPMSG_SANDBOX) += sandbox_test_rpmsg.o
 
+# Sample driver demonstrate how to use rpmsg framework
+obj-$(CONFIG_RPMSG_SAMPLE_CLIENT) += rpmsg_sample_client.o
+
 # virtio driver for rpmsg
 obj-$(CONFIG_VIRTIO_RPMSG_BUS) += virtio_rpmsg_bus.o
diff --git a/drivers/rpmsg/rpmsg_sample_client.c b/drivers/rpmsg/rpmsg_sample_client.c
new file mode 100644
index 0000000000..ae591dbdde
--- /dev/null
+++ b/drivers/rpmsg/rpmsg_sample_client.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2011 Texas Instruments, Inc.
+ * Copyright (C) 2011 Google, Inc.
+ * Copyright (C) 2023, Advanced Micro Devices, Inc.
+ *
+ * Sample client that shows use of rpmsg APIs
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <log.h>
+#include <malloc.h>
+#include <rpmsg.h>
+#include <dm/device-internal.h>
+#include <dm/uclass.h>
+#include <dm/uclass-internal.h>
+#include <linux/delay.h>
+
+static int rpmsg_rx_callback(void *buf, int msg_len, u32 msgs_received)
+{
+	printf("APU: rx: %s\n", (char *)buf);
+
+	return 0;
+}
+
+static int rpmsg_sample_client_probe(struct udevice *udev)
+{
+	char data[80] = {0};
+	int i;
+
+	/* Initialize rpmsg for core 0 */
+	rpmsg_init(0);
+
+	/* wait for RPU to initialize vdev */
+	mdelay(20);
+
+	/* assume rpmsg init is already done */
+	for (i = 1; i < 5; i++) {
+		sprintf(data, "rpmsg buf %d", i);
+		printf("APU: tx: %s\n", data);
+		rpmsg_send(0, data, strlen(data));
+
+		/* 20ms delay before receiving the data */
+		mdelay(20);
+
+		rpmsg_recv(0, rpmsg_rx_callback);
+		printf("\n");
+	}
+	return 0;
+}
+
+U_BOOT_DRIVER(rpmsg_sample_client) = {
+	.name = "rpmsg-sample-client",
+	.id = UCLASS_MISC,
+	.probe = rpmsg_sample_client_probe,
+	.flags = DM_FLAG_PRE_RELOC,
+};
+
+U_BOOT_DRVINFO(rpmsg_sample_client) = {
+	.name = "rpmsg-sample-client",
+};
-- 
2.25.1