linux-kernel - [PATCH v1 2/3] ACPI: utils: Add acpi_get_first_match_physical

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Date:   Mon, 23 Jan 2023 19:10:05 +0200
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Hans de Goede <hdegoede@...hat.com>,
        "Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
        linux-acpi@...r.kernel.org, linux-kernel@...r.kernel.org,
        acpica-devel@...ts.linuxfoundation.org
Cc:     "Rafael J. Wysocki" <rafael@...nel.org>,
        Len Brown <lenb@...nel.org>,
        Robert Moore <robert.moore@...el.com>
Subject: [PATCH v1 2/3] ACPI: utils: Add acpi_get_first_match_physical_node()

There are drivers that are using a logic that is combined in the offered
acpi_get_first_match_physical_node(). The rationale to have this helper
not only redunction of the lines of code, but improving the robustness
by properly handling the reference counters on the error paths.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
---
 drivers/acpi/utils.c    | 28 ++++++++++++++++++++++++++++
 include/acpi/acpi_bus.h |  3 +++
 include/linux/acpi.h    |  6 ++++++
 3 files changed, 37 insertions(+)

diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c
index 2ea14648a661..052e263d2246 100644
--- a/drivers/acpi/utils.c
+++ b/drivers/acpi/utils.c
@@ -965,6 +965,34 @@ acpi_dev_get_first_match_dev(const char *hid, const char *uid, s64 hrv)
 }
 EXPORT_SYMBOL(acpi_dev_get_first_match_dev);
 
+/**
+ * acpi_get_first_match_physical_node - Return the physical node of 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 the physical node of the first match of ACPI device if a matching
+ * device was present at the moment of invocation, or NULL otherwise.
+ *
+ * The caller is responsible for invoking put_device() on the returned device.
+ *
+ * See additional information in acpi_dev_present() as well.
+ */
+struct device *acpi_get_first_match_physical_node(const char *hid, const char *uid, s64 hrv)
+{
+	struct acpi_device *adev;
+	struct device *dev;
+
+	adev = acpi_dev_get_first_match_dev(hid, uid, hrv);
+	if (!adev)
+		return NULL;
+
+	dev = get_device(acpi_get_first_physical_node(adev));
+	acpi_dev_put(adev);
+	return dev;
+}
+EXPORT_SYMBOL(acpi_get_first_match_physical_node);
+
 /**
  * acpi_reduced_hardware - Return if this is an ACPI-reduced-hw machine
  *
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 0584e9f6e339..e62af2f71362 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -777,6 +777,9 @@ acpi_dev_get_first_match_dev(const char *hid, const char *uid, s64 hrv);
 	     adev;							\
 	     adev = acpi_dev_get_next_match_dev(adev, hid, uid, hrv))
 
+struct device *
+acpi_get_first_match_physical_node(const char *hid, const char *uid, s64 hrv);
+
 static inline struct acpi_device *acpi_dev_get(struct acpi_device *adev)
 {
 	return adev ? to_acpi_device(get_device(&adev->dev)) : NULL;
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 4b12dad5a8a4..29bae77d819a 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -814,6 +814,12 @@ acpi_dev_get_first_match_dev(const char *hid, const char *uid, s64 hrv)
 	return NULL;
 }
 
+static inline struct device *
+acpi_get_first_match_physical_node(const char *hid, const char *uid, s64 hrv)
+{
+	return NULL;
+}
+
 static inline bool acpi_reduced_hardware(void)
 {
 	return false;
-- 
2.39.0