[PATCH v3 01/10] ACPI / utils: Introduce acpi_dev_get_first_match_dev() helper

Andy Shevchenko
2019-03-28T17:17:20Z

The acpi_dev_get_first_match_name() is missing put_device() call
and thus keeping reference counting unbalanced.

In order to fix the issue introduce a new helper to convert existing users
one-by-one to a better API. And then remove the old one.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
---
drivers/acpi/utils.c | 24 ++++++++++++++++++++++--
include/acpi/acpi_bus.h | 3 +++
include/linux/acpi.h | 6 ++++++
3 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c
index c4b06cc075f9..5a2bae2b6c3a 100644
--- a/drivers/acpi/utils.c
+++ b/drivers/acpi/utils.c
@@ -739,6 +739,7 @@ EXPORT_SYMBOL(acpi_dev_found);

struct acpi_dev_match_info {
const char *dev_name;
+ struct acpi_device *adev;
struct acpi_device_id hid[2];
const char *uid;
s64 hrv;
@@ -759,6 +760,7 @@ static int acpi_dev_match_cb(struct device *dev, void *data)
return 0;

match->dev_name = acpi_dev_name(adev);
+ match->adev = adev;

if (match->hrv == -1)
return 1;
@@ -806,16 +808,34 @@ bool acpi_dev_present(const char *hid, const char *uid, s64 hrv)
EXPORT_SYMBOL(acpi_dev_present);

/**
- * acpi_dev_get_first_match_name - Return name of first match of ACPI device
+ * acpi_dev_get_first_match_dev - Return the first match of ACPI device
* @hid: Hardware ID of the device.
* @uid: Unique ID of the device, pass NULL to not check _UID
* @hrv: Hardware Revision of the device, pass -1 to not check _HRV
*
- * Return device name if a matching device was present
+ * Return the first match of ACPI device if a matching device was present
* at the moment of invocation, or NULL otherwise.
*
+ * The caller is responsible to call put_device() on the returned device.
+ *
* See additional information in acpi_dev_present() as well.
*/
+struct acpi_device *
+acpi_dev_get_first_match_dev(const char *hid, const char *uid, s64 hrv)
+{
+ struct acpi_dev_match_info match = {};
+ struct device *dev;
+
+ strlcpy(match.hid[0].id, hid, sizeof(match.hid[0].id));
+ match.uid = uid;
+ match.hrv = hrv;
+
+ dev = bus_find_device(&acpi_bus_type, NULL, &match, acpi_dev_match_cb);
+ return dev ? match.adev : NULL;
+}
+EXPORT_SYMBOL(acpi_dev_get_first_match_dev);
+
+/* DEPRECATED, use acpi_dev_get_first_match_dev() instead */
const char *
acpi_dev_get_first_match_name(const char *hid, const char *uid, s64 hrv)
{
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 0300374101cd..2063e9e2f384 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -91,6 +91,9 @@ acpi_evaluate_dsm_typed(acpi_handle handle, const guid_t *guid, u64 rev,
bool acpi_dev_found(const char *hid);
bool acpi_dev_present(const char *hid, const char *uid, s64 hrv);

+struct acpi_device *
+acpi_dev_get_first_match_dev(const char *hid, const char *uid, s64 hrv);
+
const char *
acpi_dev_get_first_match_name(const char *hid, const char *uid, s64 hrv);

diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index d5dcebd7aad3..3e1d16b00513 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -669,6 +669,12 @@ static inline bool acpi_dev_present(const char *hid, const char *uid, s64 hrv)
return false;
}

+static inline struct acpi_device *
+acpi_dev_get_first_match_dev(const char *hid, const char *uid, s64 hrv)
+{
+ return NULL;
+}
+
static inline const char *
acpi_dev_get_first_match_name(const char *hid, const char *uid, s64 hrv)
{
--
2.20.1