[PATCH v3 4/5] staging: vchiq: Make creation of vchiq cdev optional

[Ojaswin Mujoo]

Before this commit, vchiq cdev (/dev/vchiq) was always created during
platform initialization. Introduce a new Kconfig option
CONFIG_VCHIQ_CDEV which determines if the cdev will be created or not.

Signed-off-by: Ojaswin Mujoo <ojaswin98 at gmail.com>
---
 drivers/staging/vc04_services/Kconfig                  | 10 ++++++++++
 drivers/staging/vc04_services/Makefile                 |  5 ++++-
 .../vc04_services/interface/vchiq_arm/vchiq_arm.h      |  9 +++++++++
 3 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/vc04_services/Kconfig b/drivers/staging/vc04_services/Kconfig
index 4b886293f198..63caa6818d37 100644
--- a/drivers/staging/vc04_services/Kconfig
+++ b/drivers/staging/vc04_services/Kconfig
@@ -19,6 +19,16 @@ config BCM2835_VCHIQ
 		Defaults to Y when the Broadcom Videocore services
 		are included in the build, N otherwise.
 
+if BCM2835_VCHIQ
+
+config VCHIQ_CDEV
+	bool "VCHIQ Character Driver"
+	help
+		Enable the creation of VCHIQ character driver to help
+		communicate with the Videocore platform.
+
+endif
+
 source "drivers/staging/vc04_services/bcm2835-audio/Kconfig"
 
 source "drivers/staging/vc04_services/bcm2835-camera/Kconfig"
diff --git a/drivers/staging/vc04_services/Makefile b/drivers/staging/vc04_services/Makefile
index db28be341239..0a04338fc962 100644
--- a/drivers/staging/vc04_services/Makefile
+++ b/drivers/staging/vc04_services/Makefile
@@ -7,7 +7,10 @@ vchiq-objs := \
    interface/vchiq_arm/vchiq_2835_arm.o \
    interface/vchiq_arm/vchiq_debugfs.o \
    interface/vchiq_arm/vchiq_connected.o \
-   interface/vchiq_arm/vchiq_dev.o \
+
+ifdef CONFIG_VCHIQ_CDEV
+vchiq-objs += interface/vchiq_arm/vchiq_dev.o
+endif
 
 obj-$(CONFIG_SND_BCM2835)		+= bcm2835-audio/
 obj-$(CONFIG_VIDEO_BCM2835)		+= bcm2835-camera/
diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
index 2453971b6b78..e8e39a154c74 100644
--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
@@ -174,12 +174,21 @@ vchiq_instance_get_trace(struct vchiq_instance *instance);
 extern void
 vchiq_instance_set_trace(struct vchiq_instance *instance, int trace);
 
+#if IS_ENABLED(CONFIG_VCHIQ_CDEV)
+
 extern void
 vchiq_deregister_chrdev(void);
 
 extern int
 vchiq_register_chrdev(struct device *parent);
 
+#else
+
+static inline void vchiq_deregister_chrdev(void) { }
+static inline int vchiq_register_chrdev(struct device *parent) { return 0; }
+
+#endif /* IS_ENABLED(CONFIG_VCHIQ_CDEV) */
+
 extern enum vchiq_status
 service_callback(enum vchiq_reason reason, struct vchiq_header *header,
 		 unsigned int handle, void *bulk_userdata);
-- 
2.25.1