Based on an initial patch from Ohad Ben-Cohen.
Signed-off-by: Ohad Ben-Cohen <ohad@xxxxxxxxxx>
[s-anna@xxxxxx: forward port, add sysfs documentation, fixup qcom drivers]
Signed-off-by: Suman Anna <s-anna@xxxxxx>
[t-kristo@xxxxxx: reworked to support both rpmsg with/without the desc field]
Signed-off-by: Tero Kristo <t-kristo@xxxxxx>
---
v2:
- Localized the desc match check to virtio-rpmsg-bus
- Enforced NULL termination of desc similar to name
v1: https://patchwork.kernel.org/patch/11087717/
Documentation/ABI/testing/sysfs-bus-rpmsg | 29 ++++++++++
drivers/rpmsg/qcom_glink_native.c | 1 +
drivers/rpmsg/qcom_smd.c | 1 +
drivers/rpmsg/rpmsg_char.c | 1 +
drivers/rpmsg/rpmsg_core.c | 2 +
drivers/rpmsg/virtio_rpmsg_bus.c | 67 +++++++++++++++++++++--
drivers/soc/qcom/wcnss_ctrl.c | 1 +
include/linux/rpmsg.h | 4 ++
8 files changed, 101 insertions(+), 5 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-bus-rpmsg b/Documentation/ABI/testing/sysfs-bus-rpmsg
index 990fcc420935..7f1b09ecc64d 100644
--- a/Documentation/ABI/testing/sysfs-bus-rpmsg
+++ b/Documentation/ABI/testing/sysfs-bus-rpmsg
@@ -93,3 +93,32 @@ Description:
This sysfs entry allows the rpmsg driver for a rpmsg device
to be specified which will override standard OF, ID table
and name matching.
+
+What: /sys/bus/rpmsg/devices/.../desc
+Date: August 2019
+KernelVersion: 5.4
+Contact: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
+Description:
+ Every rpmsg device is a communication channel with a remote
+ processor. Channels are identified by a textual name (see
+ /sys/bus/rpmsg/devices/.../name above) and have a local
+ ("source") rpmsg address, and remote ("destination") rpmsg
+ address.
+
+ A channel is first created when an entity, whether local
+ or remote, starts listening on it for messages (and is thus
+ called an rpmsg server). When that happens, a "name service"
+ announcement is sent to the other processor, in order to let
+ it know about the creation of the channel (this way remote
+ clients know they can start sending messages).
+
+ The listening entity (or client) which communicates with a
+ remote processor is referred as rpmsg driver. The rpmsg device
+ and rpmsg driver are matched based on rpmsg device name (see
+ /sys/bus/rpmsg/devices/.../name above) and rpmsg driver ID table.
+
+ This sysfs entry contains an additional optional description of
+ the rpmsg device that can be optionally included as part of the
+ "name service" announcement. This description is then passed on
+ to the corresponding rpmsg drivers to further distinguish multiple
+ devices associated with the same rpmsg driver.
diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c
index f46c787733e8..cfdabddc15ac 100644
--- a/drivers/rpmsg/qcom_glink_native.c
+++ b/drivers/rpmsg/qcom_glink_native.c
@@ -1456,6 +1456,7 @@ static void qcom_glink_rx_close(struct qcom_glink *glink, unsigned int rcid)
strncpy(chinfo.name, channel->name, sizeof(chinfo.name));
chinfo.src = RPMSG_ADDR_ANY;
chinfo.dst = RPMSG_ADDR_ANY;
+ chinfo.desc[0] = '\0';
rpmsg_unregister_device(glink->dev, &chinfo);
}
diff --git a/drivers/rpmsg/qcom_smd.c b/drivers/rpmsg/qcom_smd.c
index 4abbeea782fa..7cd6b9c47065 100644
--- a/drivers/rpmsg/qcom_smd.c
+++ b/drivers/rpmsg/qcom_smd.c
@@ -1307,6 +1307,7 @@ static void qcom_channel_state_worker(struct work_struct *work)
strncpy(chinfo.name, channel->name, sizeof(chinfo.name));
chinfo.src = RPMSG_ADDR_ANY;
chinfo.dst = RPMSG_ADDR_ANY;
+ chinfo.desc[0] = '\0';
rpmsg_unregister_device(&edge->dev, &chinfo);
channel->registered = false;
spin_lock_irqsave(&edge->channels_lock, flags);
diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c
index eea5ebbb5119..4bd91445a2fd 100644
--- a/drivers/rpmsg/rpmsg_char.c
+++ b/drivers/rpmsg/rpmsg_char.c
@@ -442,6 +442,7 @@ static long rpmsg_ctrldev_ioctl(struct file *fp, unsigned int cmd,
chinfo.name[RPMSG_NAME_SIZE-1] = '\0';
chinfo.src = eptinfo.src;
chinfo.dst = eptinfo.dst;
+ chinfo.desc[0] = '\0';
return rpmsg_eptdev_create(ctrldev, chinfo);
};
diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
index ea88fd4e2a6e..ba0f2c1a7fa4 100644
--- a/drivers/rpmsg/rpmsg_core.c
+++ b/drivers/rpmsg/rpmsg_core.c
@@ -365,6 +365,7 @@ static DEVICE_ATTR_RW(field)
/* for more info, see Documentation/ABI/testing/sysfs-bus-rpmsg */
rpmsg_show_attr(name, id.name, "%s\n");
+rpmsg_show_attr(desc, desc, "%s\n");
rpmsg_show_attr(src, src, "0x%x\n");
rpmsg_show_attr(dst, dst, "0x%x\n");
rpmsg_show_attr(announce, announce ? "true" : "false", "%s\n");
@@ -386,6 +387,7 @@ static DEVICE_ATTR_RO(modalias);
static struct attribute *rpmsg_dev_attrs[] = {
&dev_attr_name.attr,
+ &dev_attr_desc.attr,
&dev_attr_modalias.attr,
&dev_attr_dst.attr,
&dev_attr_src.attr,
diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index 5d3685bd76a2..b42277cd7759 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -110,6 +110,23 @@ struct rpmsg_ns_msg {
u32 flags;
} __packed;
+/**
+ * struct rpmsg_ns_msg_ext - dynamic name service announcement message v2
+ * @name: name of remote service that is published
+ * @desc: description of remote service
+ * @addr: address of remote service that is published
+ * @flags: indicates whether service is created or destroyed
+ *
+ * Interchangeable nameservice message with rpmsg_ns_msg. This one has
+ * the addition of the desc field for extra flexibility.
+ */
+struct rpmsg_ns_msg_ext {
+ char name[RPMSG_NAME_SIZE];
+ char desc[RPMSG_NAME_SIZE];
+ u32 addr;
+ u32 flags;
+} __packed;
+
/**
* enum rpmsg_ns_flags - dynamic name service announcement flags
*
@@ -384,6 +401,24 @@ static void virtio_rpmsg_release_device(struct device *dev)
kfree(vch);
}
+static int virtio_rpmsg_desc_match(struct device *dev, void *data)
+{
+ struct rpmsg_channel_info *chinfo = data;
+ struct rpmsg_device *rpdev = to_rpmsg_device(dev);
+
+ if (!*chinfo->desc)
+ return 0;
+
+ if (strncmp(chinfo->name, rpdev->id.name, RPMSG_NAME_SIZE))
+ return 0;
+
+ if (strncmp(chinfo->desc, rpdev->desc, RPMSG_NAME_SIZE))
+ return 0;
+
+ /* found a match ! */
+ return 1;
+}
+
/*
* create an rpmsg channel using its name and address info.
* this function will be used to create both static and dynamic
@@ -407,6 +442,15 @@ static struct rpmsg_device *rpmsg_create_channel(struct virtproc_info *vrp,
return NULL;
}
+ tmp = device_find_child(dev, chinfo, virtio_rpmsg_desc_match);
+ if (tmp) {
+ /* decrement the matched device's refcount back */
+ put_device(tmp);
+ dev_err(dev, "channel %s:%x:%x failed, desc '%s' already exists\n",
+ chinfo->name, chinfo->src, chinfo->dst, chinfo->desc);
+ return NULL;
+ }
+
vch = kzalloc(sizeof(*vch), GFP_KERNEL);
if (!vch)
return NULL;
@@ -419,6 +463,7 @@ static struct rpmsg_device *rpmsg_create_channel(struct virtproc_info *vrp,
rpdev->src = chinfo->src;
rpdev->dst = chinfo->dst;
rpdev->ops = &virtio_rpmsg_ops;
+ strncpy(rpdev->desc, chinfo->desc, RPMSG_NAME_SIZE);
/*
* rpmsg server channels has predefined local address (for now),
@@ -816,18 +861,30 @@ static int rpmsg_ns_cb(struct rpmsg_device *rpdev, void *data, int len,
void *priv, u32 src)
{
struct rpmsg_ns_msg *msg = data;
+ struct rpmsg_ns_msg_ext *msg_ext = data;
struct rpmsg_device *newch;
struct rpmsg_channel_info chinfo;
struct virtproc_info *vrp = priv;
struct device *dev = &vrp->vdev->dev;
int ret;
+ u32 addr;
+ u32 flags;
#if defined(CONFIG_DYNAMIC_DEBUG)
dynamic_hex_dump("NS announcement: ", DUMP_PREFIX_NONE, 16, 1,
data, len, true);
#endif
- if (len != sizeof(*msg)) {
+ if (len == sizeof(*msg)) {
+ addr = msg->addr;
+ flags = msg->flags;
+ chinfo.desc[0] = '\0';
+ } else if (len == sizeof(*msg_ext)) {
+ addr = msg_ext->addr;
+ flags = msg_ext->flags;
+ msg_ext->desc[RPMSG_NAME_SIZE - 1] = '\0';
+ strncpy(chinfo.desc, msg_ext->desc, sizeof(chinfo.desc));
+ } else {
dev_err(dev, "malformed ns msg (%d)\n", len);
return -EINVAL;
}
@@ -847,14 +904,14 @@ static int rpmsg_ns_cb(struct rpmsg_device *rpdev, void *data, int len,
msg->name[RPMSG_NAME_SIZE - 1] = '\0';
dev_info(dev, "%sing channel %s addr 0x%x\n",
- msg->flags & RPMSG_NS_DESTROY ? "destroy" : "creat",
- msg->name, msg->addr);
+ flags & RPMSG_NS_DESTROY ? "destroy" : "creat",
+ msg->name, addr);
strncpy(chinfo.name, msg->name, sizeof(chinfo.name));
chinfo.src = RPMSG_ADDR_ANY;
- chinfo.dst = msg->addr;
+ chinfo.dst = addr;
- if (msg->flags & RPMSG_NS_DESTROY) {
+ if (flags & RPMSG_NS_DESTROY) {
ret = rpmsg_unregister_device(&vrp->vdev->dev, &chinfo);
if (ret)
dev_err(dev, "rpmsg_destroy_channel failed: %d\n", ret);
diff --git a/drivers/soc/qcom/wcnss_ctrl.c b/drivers/soc/qcom/wcnss_ctrl.c
index e5c68051fb17..ad9f28dc13f1 100644
--- a/drivers/soc/qcom/wcnss_ctrl.c
+++ b/drivers/soc/qcom/wcnss_ctrl.c
@@ -276,6 +276,7 @@ struct rpmsg_endpoint *qcom_wcnss_open_channel(void *wcnss, const char *name, rp
strscpy(chinfo.name, name, sizeof(chinfo.name));
chinfo.src = RPMSG_ADDR_ANY;
chinfo.dst = RPMSG_ADDR_ANY;
+ chinfo.desc[0] = '\0';
return rpmsg_create_ept(_wcnss->channel->rpdev, cb, priv, chinfo);
