[PATCH v2 1/8] driver core: auxiliary bus: Introduce dev_is_auxiliary()

From: Rafael J. Wysocki

Date: Fri Mar 13 2026 - 09:09:41 EST


From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

Introduce dev_is_auxiliary() in analogy with dev_is_platform() to
facilitate subsequent changes.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---

Danilo, Greg, please let me know if you have objections or concerns
regarding this one.

The new function is used in the next patch to limit the scope of the
search when looking for duplicates of the device being probed.

---
drivers/base/auxiliary.c | 10 ++++++++++
include/linux/auxiliary_bus.h | 2 ++
2 files changed, 12 insertions(+)

--- a/drivers/base/auxiliary.c
+++ b/drivers/base/auxiliary.c
@@ -502,6 +502,16 @@ struct auxiliary_device *__devm_auxiliar
}
EXPORT_SYMBOL_GPL(__devm_auxiliary_device_create);

+/**
+ * dev_is_auxiliary - check if the device is an auxiliary one
+ * @dev: device to check
+ */
+bool dev_is_auxiliary(struct device *dev)
+{
+ return dev->bus == &auxiliary_bus_type;
+}
+EXPORT_SYMBOL_GPL(dev_is_auxiliary);
+
void __init auxiliary_bus_init(void)
{
WARN_ON(bus_register(&auxiliary_bus_type));
--- a/include/linux/auxiliary_bus.h
+++ b/include/linux/auxiliary_bus.h
@@ -271,6 +271,8 @@ struct auxiliary_device *__devm_auxiliar
__devm_auxiliary_device_create(dev, KBUILD_MODNAME, devname, \
platform_data, 0)

+bool dev_is_auxiliary(struct device *dev);
+
/**
* module_auxiliary_driver() - Helper macro for registering an auxiliary driver
* @__auxiliary_driver: auxiliary driver struct