remoteproc: Introducing function rproc_validate()

Add a new function to assert the general health of the remote
processor before handing it to the remoteproc core.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Tested-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Link: https://lore.kernel.org/r/20200714195035.1426873-6-mathieu.poirier@linaro.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index a62c4a7..7e6b17a 100644 (file)
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -2043,6 +2043,43 @@ struct rproc *rproc_get_by_phandle(phandle phandle)
 #endif
 EXPORT_SYMBOL(rproc_get_by_phandle);
 
+static int rproc_validate(struct rproc *rproc)
+{
+       switch (rproc->state) {
+       case RPROC_OFFLINE:
+               /*
+                * An offline processor without a start()
+                * function makes no sense.
+                */
+               if (!rproc->ops->start)
+                       return -EINVAL;
+               break;
+       case RPROC_DETACHED:
+               /*
+                * A remote processor in a detached state without an
+                * attach() function makes not sense.
+                */
+               if (!rproc->ops->attach)
+                       return -EINVAL;
+               /*
+                * When attaching to a remote processor the device memory
+                * is already available and as such there is no need to have a
+                * cached table.
+                */
+               if (rproc->cached_table)
+                       return -EINVAL;
+               break;
+       default:
+               /*
+                * When adding a remote processor, the state of the device
+                * can be offline or detached, nothing else.
+                */
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
 /**
  * rproc_add() - register a remote processor
  * @rproc: the remote processor handle to register
@@ -2072,6 +2109,10 @@ int rproc_add(struct rproc *rproc)
        if (ret < 0)
                return ret;
 
+       ret = rproc_validate(rproc);
+       if (ret < 0)
+               return ret;
+
        dev_info(dev, "%s is available\n", rproc->name);
 
        /* create debugfs entries */