[PATCH v2] fsl-mc: add helper macro to determine if a device is of fsl_mc type

[Nipun Gupta]

Add a helper macro to return if a device has a bus type of fsl_mc.
This makes the bus driver code more readable and provides a way for
drivers like the SMMU driver to easily check the bus type.

Signed-off-by: Nipun Gupta <nipun.gupta@xxxxxxx>
Signed-off-by: Bharat Bhushan <bharat.bhushan@xxxxxxx>
---
 drivers/staging/fsl-mc/bus/dprc-driver.c               | 4 ++--
 drivers/staging/fsl-mc/bus/irq-gic-v3-its-fsl-mc-msi.c | 2 +-
 drivers/staging/fsl-mc/bus/mc-allocator.c              | 6 +++---
 drivers/staging/fsl-mc/bus/mc-bus.c                    | 6 +++---
 drivers/staging/fsl-mc/include/mc.h                    | 7 +++++++
 5 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/drivers/staging/fsl-mc/bus/dprc-driver.c b/drivers/staging/fsl-mc/bus/dprc-driver.c
index 7fc4717..cd6d75a 100644
--- a/drivers/staging/fsl-mc/bus/dprc-driver.c
+++ b/drivers/staging/fsl-mc/bus/dprc-driver.c
@@ -649,7 +649,7 @@ static int dprc_probe(struct fsl_mc_device *mc_dev)
 		/*
 		 * This is a child DPRC:
 		 */
-		if (WARN_ON(parent_dev->bus != &fsl_mc_bus_type))
+		if (WARN_ON(!dev_is_fsl_mc(parent_dev)))
 			return -EINVAL;
 
 		if (WARN_ON(mc_dev->obj_desc.region_count == 0))
@@ -681,7 +681,7 @@ static int dprc_probe(struct fsl_mc_device *mc_dev)
 		 */
 		struct irq_domain *mc_msi_domain;
 
-		if (WARN_ON(parent_dev->bus == &fsl_mc_bus_type))
+		if (WARN_ON(dev_is_fsl_mc(parent_dev)))
 			return -EINVAL;
 
 		error = fsl_mc_find_msi_domain(parent_dev,
diff --git a/drivers/staging/fsl-mc/bus/irq-gic-v3-its-fsl-mc-msi.c b/drivers/staging/fsl-mc/bus/irq-gic-v3-its-fsl-mc-msi.c
index 720e2b0..d0c20d6 100644
--- a/drivers/staging/fsl-mc/bus/irq-gic-v3-its-fsl-mc-msi.c
+++ b/drivers/staging/fsl-mc/bus/irq-gic-v3-its-fsl-mc-msi.c
@@ -35,7 +35,7 @@ static int its_fsl_mc_msi_prepare(struct irq_domain *msi_domain,
 	struct fsl_mc_device *mc_bus_dev;
 	struct msi_domain_info *msi_info;
 
-	if (WARN_ON(dev->bus != &fsl_mc_bus_type))
+	if (WARN_ON(!dev_is_fsl_mc(dev)))
 		return -EINVAL;
 
 	mc_bus_dev = to_fsl_mc_device(dev);
diff --git a/drivers/staging/fsl-mc/bus/mc-allocator.c b/drivers/staging/fsl-mc/bus/mc-allocator.c
index fb08f22..9216c32 100644
--- a/drivers/staging/fsl-mc/bus/mc-allocator.c
+++ b/drivers/staging/fsl-mc/bus/mc-allocator.c
@@ -281,7 +281,7 @@ int __must_check fsl_mc_portal_allocate(struct fsl_mc_device *mc_dev,
 	if (mc_dev->flags & FSL_MC_IS_DPRC) {
 		mc_bus_dev = mc_dev;
 	} else {
-		if (WARN_ON(mc_dev->dev.parent->bus != &fsl_mc_bus_type))
+		if (WARN_ON(!dev_is_fsl_mc(mc_dev->dev.parent)))
 			return error;
 
 		mc_bus_dev = to_fsl_mc_device(mc_dev->dev.parent);
@@ -420,7 +420,7 @@ int __must_check fsl_mc_object_allocate(struct fsl_mc_device *mc_dev,
 	if (WARN_ON(mc_dev->flags & FSL_MC_IS_DPRC))
 		goto error;
 
-	if (WARN_ON(mc_dev->dev.parent->bus != &fsl_mc_bus_type))
+	if (WARN_ON(!dev_is_fsl_mc(mc_dev->dev.parent)))
 		goto error;
 
 	if (WARN_ON(pool_type == FSL_MC_POOL_DPMCP))
@@ -678,7 +678,7 @@ static int fsl_mc_allocator_probe(struct fsl_mc_device *mc_dev)
 		return -EINVAL;
 
 	mc_bus_dev = to_fsl_mc_device(mc_dev->dev.parent);
-	if (WARN_ON(mc_bus_dev->dev.bus != &fsl_mc_bus_type))
+	if (WARN_ON(!dev_is_fsl_mc(&mc_bus_dev->dev)))
 		return -EINVAL;
 
 	mc_bus = to_fsl_mc_bus(mc_bus_dev);
diff --git a/drivers/staging/fsl-mc/bus/mc-bus.c b/drivers/staging/fsl-mc/bus/mc-bus.c
index 4053643..098f07c 100644
--- a/drivers/staging/fsl-mc/bus/mc-bus.c
+++ b/drivers/staging/fsl-mc/bus/mc-bus.c
@@ -207,11 +207,11 @@ static void fsl_mc_get_root_dprc(struct device *dev,
 {
 	if (WARN_ON(!dev)) {
 		*root_dprc_dev = NULL;
-	} else if (WARN_ON(dev->bus != &fsl_mc_bus_type)) {
+	} else if (WARN_ON(!dev_is_fsl_mc(dev))) {
 		*root_dprc_dev = NULL;
 	} else {
 		*root_dprc_dev = dev;
-		while ((*root_dprc_dev)->parent->bus == &fsl_mc_bus_type)
+		while (dev_is_fsl_mc((*root_dprc_dev)->parent))
 			*root_dprc_dev = (*root_dprc_dev)->parent;
 	}
 }
@@ -405,7 +405,7 @@ int fsl_mc_device_add(struct dprc_obj_desc *obj_desc,
 	struct fsl_mc_bus *mc_bus = NULL;
 	struct fsl_mc_device *parent_mc_dev;
 
-	if (parent_dev->bus == &fsl_mc_bus_type)
+	if (dev_is_fsl_mc(parent_dev))
 		parent_mc_dev = to_fsl_mc_device(parent_dev);
 	else
 		parent_mc_dev = NULL;
diff --git a/drivers/staging/fsl-mc/include/mc.h b/drivers/staging/fsl-mc/include/mc.h
index ac7c1ce..91213f5 100644
--- a/drivers/staging/fsl-mc/include/mc.h
+++ b/drivers/staging/fsl-mc/include/mc.h
@@ -183,6 +183,13 @@ struct fsl_mc_device {
 #define to_fsl_mc_device(_dev) \
 	container_of(_dev, struct fsl_mc_device, dev)
 
+#ifdef CONFIG_FSL_MC_BUS
+#define dev_is_fsl_mc(_dev) ((_dev)->bus == &fsl_mc_bus_type)
+#else
+/* If fsl-mc bus is not present device cannot belong to fsl-mc bus */
+#define dev_is_fsl_mc(_dev) (0)
+#endif
+
 /*
  * module_fsl_mc_driver() - Helper macro for drivers that don't do
  * anything special in module init/exit.  This eliminates a lot of
-- 
1.9.1