From 60ba032ed76e851d30d4fa514847285252147d07 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 5 Nov 2014 00:29:07 +0100 Subject: [PATCH] ACPI / property: Drop size_prop from acpi_dev_get_property_reference() The size_prop argument of the recently added function acpi_dev_get_property_reference() is not used by the only current caller of that function and is very unlikely to be used at any time going forward. Namely, for a property whose value is a list of items each containing a references to a device object possibly accompanied by some integers, the number of items in the list can always be computed as the number of elements of type ACPI_TYPE_LOCAL_REFERENCE in the property package. Thus it should never be necessary to provide an additional "cells" property with a value equal to the number of items in that list. It also should never be necessary to provide a "cells" property specifying how many integers are supposed to be following each reference. For this reason, drop the size_prop argument from acpi_dev_get_property_reference() and update its caller accordingly. Link: http://marc.info/?l=linux-kernel&m=141511255610556&w=2 Suggested-by: Grant Likely Acked-by: Grant Likely Acked-by: Mika Westerberg Tested-by: Mika Westerberg Signed-off-by: Rafael J. Wysocki --- drivers/acpi/property.c | 60 ++++++++++--------------------------- drivers/gpio/gpiolib-acpi.c | 2 +- include/linux/acpi.h | 4 +-- 3 files changed, 18 insertions(+), 48 deletions(-) diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c index 27add91bc270..0d083736e25b 100644 --- a/drivers/acpi/property.c +++ b/drivers/acpi/property.c @@ -273,25 +273,21 @@ EXPORT_SYMBOL_GPL(acpi_dev_get_property_array); * acpi_dev_get_property_reference - returns handle to the referenced object * @adev: ACPI device to get property * @name: Name of the property - * @size_prop: Name of the "size" property in referenced object * @index: Index of the reference to return * @args: Location to store the returned reference with optional arguments * * Find property with @name, verifify that it is a package containing at least * one object reference and if so, store the ACPI device object pointer to the - * target object in @args->adev. + * target object in @args->adev. If the reference includes arguments, store + * them in the @args->args[] array. * - * If the reference includes arguments (@size_prop is not %NULL) follow the - * reference and check whether or not there is an integer property @size_prop - * under the target object and if so, whether or not its value matches the - * number of arguments that follow the reference. If there's more than one - * reference in the property value package, @index is used to select the one to - * return. + * If there's more than one reference in the property value package, @index is + * used to select the one to return. * * Return: %0 on success, negative error code on failure. */ -int acpi_dev_get_property_reference(struct acpi_device *adev, const char *name, - const char *size_prop, size_t index, +int acpi_dev_get_property_reference(struct acpi_device *adev, + const char *name, size_t index, struct acpi_reference_args *args) { const union acpi_object *element, *end; @@ -308,7 +304,7 @@ int acpi_dev_get_property_reference(struct acpi_device *adev, const char *name, * return that reference then. */ if (obj->type == ACPI_TYPE_LOCAL_REFERENCE) { - if (size_prop || index) + if (index) return -EINVAL; ret = acpi_bus_get_device(obj->reference.handle, &device); @@ -348,42 +344,16 @@ int acpi_dev_get_property_reference(struct acpi_device *adev, const char *name, element++; nargs = 0; - if (size_prop) { - const union acpi_object *prop; + /* assume following integer elements are all args */ + for (i = 0; element + i < end; i++) { + int type = element[i].type; - /* - * Find out how many arguments the refenced object - * expects by reading its size_prop property. - */ - ret = acpi_dev_get_property(device, size_prop, - ACPI_TYPE_INTEGER, &prop); - if (ret) - return ret; - - nargs = prop->integer.value; - if (nargs > MAX_ACPI_REFERENCE_ARGS - || element + nargs > end) + if (type == ACPI_TYPE_INTEGER) + nargs++; + else if (type == ACPI_TYPE_LOCAL_REFERENCE) + break; + else return -EPROTO; - - /* - * Skip to the start of the arguments and verify - * that they all are in fact integers. - */ - for (i = 0; i < nargs; i++) - if (element[i].type != ACPI_TYPE_INTEGER) - return -EPROTO; - } else { - /* assume following integer elements are all args */ - for (i = 0; element + i < end; i++) { - int type = element[i].type; - - if (type == ACPI_TYPE_INTEGER) - nargs++; - else if (type == ACPI_TYPE_LOCAL_REFERENCE) - break; - else - return -EPROTO; - } } if (idx++ == index) { diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c index 5a4d061e787e..ba98bb59a58f 100644 --- a/drivers/gpio/gpiolib-acpi.c +++ b/drivers/gpio/gpiolib-acpi.c @@ -405,7 +405,7 @@ struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev, dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname); memset(&args, 0, sizeof(args)); - ret = acpi_dev_get_property_reference(adev, propname, NULL, + ret = acpi_dev_get_property_reference(adev, propname, index, &args); if (ret) { bool found = acpi_get_driver_gpio_data(adev, propname, diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 0902426c4521..10f2ed95645c 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -718,8 +718,8 @@ int acpi_dev_get_property(struct acpi_device *adev, const char *name, int acpi_dev_get_property_array(struct acpi_device *adev, const char *name, acpi_object_type type, const union acpi_object **obj); -int acpi_dev_get_property_reference(struct acpi_device *adev, const char *name, - const char *cells_name, size_t index, +int acpi_dev_get_property_reference(struct acpi_device *adev, + const char *name, size_t index, struct acpi_reference_args *args); int acpi_dev_prop_get(struct acpi_device *adev, const char *propname,