[PATCH 3/4] rpmsg: char: Introduce the "rpmsg-raw" channel

Arnaud Pouliquen
2021-06-07T17:30:55Z

Allows to probe the endpoint device on a remote name service announcement,
by registering a rpmsg_driverfor the "rpmsg-raw" channel.

With this patch the /dev/rpmsgX interface can be instantiated by the remote
firmware.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
---
drivers/rpmsg/rpmsg_char.c | 54 ++++++++++++++++++++++++++++++++++++--
1 file changed, 52 insertions(+), 2 deletions(-)

diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c
index 4199ac1bee10..3b850b218eb0 100644
--- a/drivers/rpmsg/rpmsg_char.c
+++ b/drivers/rpmsg/rpmsg_char.c
@@ -25,6 +25,8 @@

#include "rpmsg_char.h"

+#define RPMSG_CHAR_DEVNAME "rpmsg-raw"
+
static dev_t rpmsg_major;
static struct class *rpmsg_class;

@@ -416,6 +418,40 @@ int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent
}
EXPORT_SYMBOL(rpmsg_chrdev_eptdev_create);

+static int rpmsg_chrdev_probe(struct rpmsg_device *rpdev)
+{
+ struct rpmsg_channel_info chinfo;
+
+ memcpy(chinfo.name, RPMSG_CHAR_DEVNAME, sizeof(RPMSG_CHAR_DEVNAME));
+ chinfo.src = rpdev->src;
+ chinfo.dst = rpdev->dst;
+
+ return __rpmsg_chrdev_eptdev_create(rpdev, &rpdev->dev, chinfo, true);
+}
+
+static void rpmsg_chrdev_remove(struct rpmsg_device *rpdev)
+{
+ int ret;
+
+ ret = device_for_each_child(&rpdev->dev, NULL, rpmsg_chrdev_eptdev_destroy);
+ if (ret)
+ dev_warn(&rpdev->dev, "failed to destroy endpoints: %d\n", ret);
+}
+
+static struct rpmsg_device_id rpmsg_chrdev_id_table[] = {
+ { .name = RPMSG_CHAR_DEVNAME },
+ { },
+};
+
+static struct rpmsg_driver rpmsg_chrdev_driver = {
+ .probe = rpmsg_chrdev_probe,
+ .remove = rpmsg_chrdev_remove,
+ .id_table = rpmsg_chrdev_id_table,
+ .drv = {
+ .name = "rpmsg_chrdev",
+ },
+};
+
static int rpmsg_chrdev_init(void)
{
int ret;
@@ -429,16 +465,30 @@ static int rpmsg_chrdev_init(void)
rpmsg_class = class_create(THIS_MODULE, "rpmsg");
if (IS_ERR(rpmsg_class)) {
pr_err("failed to create rpmsg class\n");
- unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
- return PTR_ERR(rpmsg_class);
+ ret = PTR_ERR(rpmsg_class);
+ goto free_region;
+ }
+
+ ret = register_rpmsg_driver(&rpmsg_chrdev_driver);
+ if (ret < 0) {
+ pr_err("rpmsg: failed to register rpmsg raw driver\n");
+ goto free_class;
}

return 0;
+
+free_class:
+ class_destroy(rpmsg_class);
+free_region:
+ unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
+
+ return ret;
}
postcore_initcall(rpmsg_chrdev_init);

static void rpmsg_chrdev_exit(void)
{
+ unregister_rpmsg_driver(&rpmsg_chrdev_driver);
class_destroy(rpmsg_class);
unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
}
--
2.17.1