rpmsg: Introduce indirection table for rpmsg_device operations

To allow for multiple backend implementations add an indireection table
for rpmsg_device related operations and move the virtio implementation
behind this table.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index 1ac9fd8..088203e 100644 (file)
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -286,10 +286,18 @@ struct rpmsg_endpoint *rpmsg_create_ept(struct rpmsg_device *rpdev,
                                        rpmsg_rx_cb_t cb, void *priv,
                                        struct rpmsg_channel_info chinfo)
 {
-       return __rpmsg_create_ept(rpdev->vrp, rpdev, cb, priv, chinfo.src);
+       return rpdev->ops->create_ept(rpdev, cb, priv, chinfo);
 }
 EXPORT_SYMBOL(rpmsg_create_ept);
 
+static struct rpmsg_endpoint *virtio_rpmsg_create_ept(struct rpmsg_device *rpdev,
+                                                     rpmsg_rx_cb_t cb,
+                                                     void *priv,
+                                                     struct rpmsg_channel_info chinfo)
+{
+       return __rpmsg_create_ept(rpdev->vrp, rpdev, cb, priv, chinfo.src);
+}
+
 /**
  * __rpmsg_destroy_ept() - destroy an existing rpmsg endpoint
  * @vrp: virtproc which owns this ept
@@ -341,7 +349,6 @@ static int rpmsg_dev_probe(struct device *dev)
 {
        struct rpmsg_device *rpdev = to_rpmsg_device(dev);
        struct rpmsg_driver *rpdrv = to_rpmsg_driver(rpdev->dev.driver);
-       struct virtproc_info *vrp = rpdev->vrp;
        struct rpmsg_channel_info chinfo = {};
        struct rpmsg_endpoint *ept;
        int err;
@@ -367,6 +374,18 @@ static int rpmsg_dev_probe(struct device *dev)
                goto out;
        }
 
+       if (rpdev->ops->announce_create)
+               err = rpdev->ops->announce_create(rpdev);
+out:
+       return err;
+}
+
+static int virtio_rpmsg_announce_create(struct rpmsg_device *rpdev)
+{
+       struct virtproc_info *vrp = rpdev->vrp;
+       struct device *dev = &rpdev->dev;
+       int err = 0;
+
        /* need to tell remote processor's name service about this channel ? */
        if (rpdev->announce &&
            virtio_has_feature(vrp->vdev, VIRTIO_RPMSG_F_NS)) {
@@ -381,15 +400,13 @@ static int rpmsg_dev_probe(struct device *dev)
                        dev_err(dev, "failed to announce service %d\n", err);
        }
 
-out:
        return err;
 }
 
-static int rpmsg_dev_remove(struct device *dev)
+static int virtio_rpmsg_announce_destroy(struct rpmsg_device *rpdev)
 {
-       struct rpmsg_device *rpdev = to_rpmsg_device(dev);
-       struct rpmsg_driver *rpdrv = to_rpmsg_driver(rpdev->dev.driver);
        struct virtproc_info *vrp = rpdev->vrp;
+       struct device *dev = &rpdev->dev;
        int err = 0;
 
        /* tell remote processor's name service we're removing this channel */
@@ -406,6 +423,18 @@ static int rpmsg_dev_remove(struct device *dev)
                        dev_err(dev, "failed to announce service %d\n", err);
        }
 
+       return err;
+}
+
+static int rpmsg_dev_remove(struct device *dev)
+{
+       struct rpmsg_device *rpdev = to_rpmsg_device(dev);
+       struct rpmsg_driver *rpdrv = to_rpmsg_driver(rpdev->dev.driver);
+       int err = 0;
+
+       if (rpdev->ops->announce_destroy)
+               err = rpdev->ops->announce_destroy(rpdev);
+
        rpdrv->remove(rpdev);
 
        rpmsg_destroy_ept(rpdev->ept);
@@ -479,6 +508,12 @@ static int rpmsg_device_match(struct device *dev, void *data)
        return 1;
 }
 
+static const struct rpmsg_device_ops virtio_rpmsg_ops = {
+       .create_ept = virtio_rpmsg_create_ept,
+       .announce_create = virtio_rpmsg_announce_create,
+       .announce_destroy = virtio_rpmsg_announce_destroy,
+};
+
 /*
  * create an rpmsg channel using its name and address info.
  * this function will be used to create both static and dynamic
@@ -508,6 +543,7 @@ static struct rpmsg_device *rpmsg_create_channel(struct virtproc_info *vrp,
        rpdev->vrp = vrp;
        rpdev->src = chinfo->src;
        rpdev->dst = chinfo->dst;
+       rpdev->ops = &virtio_rpmsg_ops;
 
        /*
         * rpmsg server channels has predefined local address (for now),

diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
index 35a0f39..9fdcfc7 100644 (file)
--- a/include/linux/rpmsg.h
+++ b/include/linux/rpmsg.h
@@ -96,6 +96,8 @@ enum rpmsg_ns_flags {
 #define RPMSG_ADDR_ANY         0xFFFFFFFF
 
 struct virtproc_info;
+struct rpmsg_endpoint;
+struct rpmsg_device_ops;
 
 /**
  * struct rpmsg_channel_info - channel info representation
@@ -127,11 +129,32 @@ struct rpmsg_device {
        u32 dst;
        struct rpmsg_endpoint *ept;
        bool announce;
+
+       const struct rpmsg_device_ops *ops;
 };
 
 typedef void (*rpmsg_rx_cb_t)(struct rpmsg_device *, void *, int, void *, u32);
 
 /**
+ * struct rpmsg_device_ops - indirection table for the rpmsg_device operations
+ * @create_ept:                create backend-specific endpoint, requried
+ * @announce_create:   announce presence of new channel, optional
+ * @announce_destroy:  announce destruction of channel, optional
+ *
+ * Indirection table for the operations that a rpmsg backend should implement.
+ * @announce_create and @announce_destroy are optional as the backend might
+ * advertise new channels implicitly by creating the endpoints.
+ */
+struct rpmsg_device_ops {
+       struct rpmsg_endpoint *(*create_ept)(struct rpmsg_device *rpdev,
+                                           rpmsg_rx_cb_t cb, void *priv,
+                                           struct rpmsg_channel_info chinfo);
+
+       int (*announce_create)(struct rpmsg_device *ept);
+       int (*announce_destroy)(struct rpmsg_device *ept);
+};
+
+/**
  * struct rpmsg_endpoint - binds a local rpmsg address to its user
  * @rpdev: rpmsg channel device
  * @refcount: when this drops to zero, the ept is deallocated