[PATCH] drivers/base: Introduce device_match_t for device finding APIs

Zijun Hu
2024-08-02T10:48:20Z

From: Zijun Hu <quic_zijuhu@quicinc.com>

There are several drivers/base APIs for finding a specific device, and
they currently use the following good type for the @match parameter:
int (*match)(struct device *dev, const void *data)

Since these operations do not modify the caller-provided @*data, this
type is worthy of a dedicated typedef:
typedef int (*device_match_t)(struct device *dev, const void *data)

Advantages of using device_match_t:
- Shorter API declarations and definitions
- Prevent further APIs from using a bad type for @match

So introduce device_match_t and apply it to the existing
(bus|class|driver|auxiliary)_find_device() APIs.

Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com>
---
drivers/base/auxiliary.c | 2 +-
drivers/base/bus.c | 2 +-
drivers/base/class.c | 3 +--
drivers/base/driver.c | 2 +-
include/linux/auxiliary_bus.h | 2 +-
include/linux/device/bus.h | 5 +++--
include/linux/device/class.h | 2 +-
include/linux/device/driver.h | 2 +-
8 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/base/auxiliary.c b/drivers/base/auxiliary.c
index 54b92839e05c..7823888af4f6 100644
--- a/drivers/base/auxiliary.c
+++ b/drivers/base/auxiliary.c
@@ -352,7 +352,7 @@ EXPORT_SYMBOL_GPL(__auxiliary_device_add);
*/
struct auxiliary_device *auxiliary_find_device(struct device *start,
const void *data,
- int (*match)(struct device *dev, const void *data))
+ device_match_t match)
{
struct device *dev;

diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index ffea0728b8b2..0de6a389d000 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -389,7 +389,7 @@ EXPORT_SYMBOL_GPL(bus_for_each_dev);
*/
struct device *bus_find_device(const struct bus_type *bus,
struct device *start, const void *data,
- int (*match)(struct device *dev, const void *data))
+ device_match_t match)
{
struct subsys_private *sp = bus_to_subsys(bus);
struct klist_iter i;
diff --git a/drivers/base/class.c b/drivers/base/class.c
index 7b38fdf8e1d7..ae22fa992c04 100644
--- a/drivers/base/class.c
+++ b/drivers/base/class.c
@@ -433,8 +433,7 @@ EXPORT_SYMBOL_GPL(class_for_each_device);
* code. There's no locking restriction.
*/
struct device *class_find_device(const struct class *class, const struct device *start,
- const void *data,
- int (*match)(struct device *, const void *))
+ const void *data, device_match_t match)
{
struct subsys_private *sp = class_to_subsys(class);
struct class_dev_iter iter;
diff --git a/drivers/base/driver.c b/drivers/base/driver.c
index 88c6fd1f1992..b4eb5b89c4ee 100644
--- a/drivers/base/driver.c
+++ b/drivers/base/driver.c
@@ -150,7 +150,7 @@ EXPORT_SYMBOL_GPL(driver_for_each_device);
*/
struct device *driver_find_device(const struct device_driver *drv,
struct device *start, const void *data,
- int (*match)(struct device *dev, const void *data))
+ device_match_t match)
{
struct klist_iter i;
struct device *dev;
diff --git a/include/linux/auxiliary_bus.h b/include/linux/auxiliary_bus.h
index 662b8ae54b6a..31762324bcc9 100644
--- a/include/linux/auxiliary_bus.h
+++ b/include/linux/auxiliary_bus.h
@@ -271,6 +271,6 @@ void auxiliary_driver_unregister(struct auxiliary_driver *auxdrv);

struct auxiliary_device *auxiliary_find_device(struct device *start,
const void *data,
- int (*match)(struct device *dev, const void *data));
+ device_match_t match);

#endif /* _AUXILIARY_BUS_H_ */
diff --git a/include/linux/device/bus.h b/include/linux/device/bus.h
index 807831d6bf0f..970de5ee5562 100644
--- a/include/linux/device/bus.h
+++ b/include/linux/device/bus.h
@@ -126,6 +126,8 @@ struct bus_attribute {
int __must_check bus_create_file(const struct bus_type *bus, struct bus_attribute *attr);
void bus_remove_file(const struct bus_type *bus, struct bus_attribute *attr);

+/* Matching function type for drivers/base APIs to find a specific device */
+typedef int (*device_match_t)(struct device *dev, const void *data);
/* Generic device matching functions that all busses can use to match with */
int device_match_name(struct device *dev, const void *name);
int device_match_of_node(struct device *dev, const void *np);
@@ -139,8 +141,7 @@ int device_match_any(struct device *dev, const void *unused);
int bus_for_each_dev(const struct bus_type *bus, struct device *start, void *data,
int (*fn)(struct device *dev, void *data));
struct device *bus_find_device(const struct bus_type *bus, struct device *start,
- const void *data,
- int (*match)(struct device *dev, const void *data));
+ const void *data, device_match_t match);
/**
* bus_find_device_by_name - device iterator for locating a particular device
* of a specific name.
diff --git a/include/linux/device/class.h b/include/linux/device/class.h
index c576b49c55c2..518c9c83d64b 100644
--- a/include/linux/device/class.h
+++ b/include/linux/device/class.h
@@ -95,7 +95,7 @@ void class_dev_iter_exit(struct class_dev_iter *iter);
int class_for_each_device(const struct class *class, const struct device *start, void *data,
int (*fn)(struct device *dev, void *data));
struct device *class_find_device(const struct class *class, const struct device *start,
- const void *data, int (*match)(struct device *, const void *));
+ const void *data, device_match_t match);

/**
* class_find_device_by_name - device iterator for locating a particular device
diff --git a/include/linux/device/driver.h b/include/linux/device/driver.h
index 1fc8b68786de..5c04b8e3833b 100644
--- a/include/linux/device/driver.h
+++ b/include/linux/device/driver.h
@@ -157,7 +157,7 @@ int __must_check driver_for_each_device(struct device_driver *drv, struct device
void *data, int (*fn)(struct device *dev, void *));
struct device *driver_find_device(const struct device_driver *drv,
struct device *start, const void *data,
- int (*match)(struct device *dev, const void *data));
+ device_match_t match);

/**
* driver_find_device_by_name - device iterator for locating a particular device

---
base-commit: 8400291e289ee6b2bf9779ff1c83a291501f017b
change-id: 20240801-dev_match_api-415a755fcffb

Best regards,
--
Zijun Hu <quic_zijuhu@quicinc.com>