[RFC PATCH 4/7] remoteproc: create the REMOTEPROC_VIRTIO config

[Arnaud Pouliquen]

Create the config to associate to the remoteproc virtio.

Notice that the REMOTEPROC_VIRTIO config can not set to m. the reason
is that it defines API that is used by the built-in remote proc core.
Functions such are rproc_add_virtio_dev can be called during the
Linux boot phase.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
---
 drivers/remoteproc/Kconfig               | 11 +++++++++-
 drivers/remoteproc/Makefile              |  2 +-
 drivers/remoteproc/remoteproc_internal.h | 28 ++++++++++++++++++++++++
 3 files changed, 39 insertions(+), 2 deletions(-)

diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
index 9a6eedc3994a..f271552c0d84 100644
--- a/drivers/remoteproc/Kconfig
+++ b/drivers/remoteproc/Kconfig
@@ -6,7 +6,7 @@ config REMOTEPROC
 	depends on HAS_DMA
 	select CRC32
 	select FW_LOADER
-	select VIRTIO
+	select REMOTEPROC_VIRTIO
 	select WANT_DEV_COREDUMP
 	help
 	  Support for remote processors (such as DSP coprocessors). These
@@ -14,6 +14,15 @@ config REMOTEPROC
 
 if REMOTEPROC
 
+config REMOTEPROC_VIRTIO
+	bool "Remoteproc virtio device "
+	select VIRTIO
+	help
+	  Say y here to have a virtio device support for the remoteproc
+	  communication.
+
+	  It's safe to say N if you don't use the virtio for the IPC.
+
 config REMOTEPROC_CDEV
 	bool "Remoteproc character device interface"
 	help
diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile
index bb26c9e4ef9c..73d2384a76aa 100644
--- a/drivers/remoteproc/Makefile
+++ b/drivers/remoteproc/Makefile
@@ -8,8 +8,8 @@ remoteproc-y				:= remoteproc_core.o
 remoteproc-y				+= remoteproc_coredump.o
 remoteproc-y				+= remoteproc_debugfs.o
 remoteproc-y				+= remoteproc_sysfs.o
-remoteproc-y				+= remoteproc_virtio.o
 remoteproc-y				+= remoteproc_elf_loader.o
+obj-$(CONFIG_REMOTEPROC_VIRTIO)		+= remoteproc_virtio.o
 obj-$(CONFIG_REMOTEPROC_CDEV)		+= remoteproc_cdev.o
 obj-$(CONFIG_IMX_REMOTEPROC)		+= imx_rproc.o
 obj-$(CONFIG_INGENIC_VPU_RPROC)		+= ingenic_rproc.o
diff --git a/drivers/remoteproc/remoteproc_internal.h b/drivers/remoteproc/remoteproc_internal.h
index 152fe2e8668a..4ce012c353c0 100644
--- a/drivers/remoteproc/remoteproc_internal.h
+++ b/drivers/remoteproc/remoteproc_internal.h
@@ -30,10 +30,38 @@ int rproc_of_parse_firmware(struct device *dev, int index,
 			    const char **fw_name);
 
 /* from remoteproc_virtio.c */
+#if IS_ENABLED(CONFIG_REMOTEPROC_VIRTIO)
+
 int rproc_rvdev_add_device(struct rproc_vdev *rvdev);
 irqreturn_t rproc_vq_interrupt(struct rproc *rproc, int vq_id);
 void rproc_vdev_release(struct kref *ref);
 
+#else
+
+int rproc_rvdev_add_device(struct rproc_vdev *rvdev)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return -ENXIO;
+}
+
+static inline irqreturn_t rproc_vq_interrupt(struct rproc *rproc, int vq_id)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return IRQ_NONE;
+}
+
+static inline void rproc_vdev_release(struct kref *ref)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+}
+
+#endif
+
 /* from remoteproc_debugfs.c */
 void rproc_remove_trace_file(struct dentry *tfile);
 struct dentry *rproc_create_trace_file(const char *name, struct rproc *rproc,
-- 
2.17.1