[PATCH v2 2/5] ACPI: Make acpi_dev_get_resources() method agnostic

From: Lorenzo Pieralisi
Date: Mon Jul 31 2017 - 11:22:54 EST


The function acpi_dev_get_resources() is completely generic and
can be used to parse resource objects that are not necessarily
coming from the _CRS method but also from other objects eg _DMA
that have the same _CRS resource format.

Create an acpi_dev_get_resources() helper, internal to the ACPI
resources parsing compilation unit, __acpi_dev_get_resources(),
that takes a const char* parameter to detect which ACPI method should be
called to retrieve the resources list and make acpi_dev_get_resources()
call it with a method name _CRS leaving the API behaviour unchanged.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
---
drivers/acpi/resource.c | 53 +++++++++++++++++++++++++++++--------------------
1 file changed, 31 insertions(+), 22 deletions(-)

diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
index cd4c427..93f1b5c 100644
--- a/drivers/acpi/resource.c
+++ b/drivers/acpi/resource.c
@@ -573,6 +573,35 @@ static acpi_status acpi_dev_process_resource(struct acpi_resource *ares,
return AE_OK;
}

+static int __acpi_dev_get_resources(struct acpi_device *adev,
+ struct list_head *list,
+ int (*preproc)(struct acpi_resource *, void *),
+ void *preproc_data, char *method)
+{
+ struct res_proc_context c;
+ acpi_status status;
+
+ if (!adev || !adev->handle || !list_empty(list))
+ return -EINVAL;
+
+ if (!acpi_has_method(adev->handle, method))
+ return 0;
+
+ c.list = list;
+ c.preproc = preproc;
+ c.preproc_data = preproc_data;
+ c.count = 0;
+ c.error = 0;
+ status = acpi_walk_resources(adev->handle, method,
+ acpi_dev_process_resource, &c);
+ if (ACPI_FAILURE(status)) {
+ acpi_dev_free_resource_list(list);
+ return c.error ? c.error : -EIO;
+ }
+
+ return c.count;
+}
+
/**
* acpi_dev_get_resources - Get current resources of a device.
* @adev: ACPI device node to get the resources for.
@@ -601,28 +630,8 @@ int acpi_dev_get_resources(struct acpi_device *adev, struct list_head *list,
int (*preproc)(struct acpi_resource *, void *),
void *preproc_data)
{
- struct res_proc_context c;
- acpi_status status;
-
- if (!adev || !adev->handle || !list_empty(list))
- return -EINVAL;
-
- if (!acpi_has_method(adev->handle, METHOD_NAME__CRS))
- return 0;
-
- c.list = list;
- c.preproc = preproc;
- c.preproc_data = preproc_data;
- c.count = 0;
- c.error = 0;
- status = acpi_walk_resources(adev->handle, METHOD_NAME__CRS,
- acpi_dev_process_resource, &c);
- if (ACPI_FAILURE(status)) {
- acpi_dev_free_resource_list(list);
- return c.error ? c.error : -EIO;
- }
-
- return c.count;
+ return __acpi_dev_get_resources(adev, list, preproc, preproc_data,
+ METHOD_NAME__CRS);
}
EXPORT_SYMBOL_GPL(acpi_dev_get_resources);

--
2.10.0