diff options
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/internal.h | 8 | ||||
| -rw-r--r-- | drivers/acpi/scan.c | 8 | ||||
| -rw-r--r-- | drivers/acpi/utils.c | 31 |
3 files changed, 40 insertions, 7 deletions
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index 11d87bf67e73..60bda0d2cf9a 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -86,6 +86,14 @@ bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent); #define ACPI_STA_DEFAULT (ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED | \ ACPI_STA_DEVICE_UI | ACPI_STA_DEVICE_FUNCTIONING) +extern struct list_head acpi_bus_id_list; + +struct acpi_device_bus_id{ + char bus_id[15]; + unsigned int instance_no; + struct list_head node; +}; + int acpi_device_add(struct acpi_device *device, void (*release)(struct device *)); void acpi_init_device_object(struct acpi_device *device, acpi_handle handle, diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index be1fc12a17ee..407a3760e8de 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -39,7 +39,7 @@ static const char *dummy_hid = "device"; static LIST_HEAD(acpi_dep_list); static DEFINE_MUTEX(acpi_dep_list_lock); -static LIST_HEAD(acpi_bus_id_list); +LIST_HEAD(acpi_bus_id_list); static DEFINE_MUTEX(acpi_scan_lock); static LIST_HEAD(acpi_scan_handlers_list); DEFINE_MUTEX(acpi_device_lock); @@ -52,12 +52,6 @@ struct acpi_dep_data { acpi_handle slave; }; -struct acpi_device_bus_id{ - char bus_id[15]; - unsigned int instance_no; - struct list_head node; -}; - void acpi_scan_lock_acquire(void) { mutex_lock(&acpi_scan_lock); diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c index 475c9079bf85..f2f9873bb5c3 100644 --- a/drivers/acpi/utils.c +++ b/drivers/acpi/utils.c @@ -29,6 +29,7 @@ #include <linux/dynamic_debug.h> #include "internal.h" +#include "sleep.h" #define _COMPONENT ACPI_BUS_COMPONENT ACPI_MODULE_NAME("utils"); @@ -709,6 +710,36 @@ bool acpi_check_dsm(acpi_handle handle, const u8 *uuid, int rev, u64 funcs) } EXPORT_SYMBOL(acpi_check_dsm); +/** + * acpi_dev_present - Detect presence of a given ACPI device in the system. + * @hid: Hardware ID of the device. + * + * Return %true if the device was present at the moment of invocation. + * Note that if the device is pluggable, it may since have disappeared. + * + * For this function to work, acpi_bus_scan() must have been executed + * which happens in the subsys_initcall() subsection. Hence, do not + * call from a subsys_initcall() or earlier (use acpi_get_devices() + * instead). Calling from module_init() is fine (which is synonymous + * with device_initcall()). + */ +bool acpi_dev_present(const char *hid) +{ + struct acpi_device_bus_id *acpi_device_bus_id; + bool found = false; + + mutex_lock(&acpi_device_lock); + list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) + if (!strcmp(acpi_device_bus_id->bus_id, hid)) { + found = true; + break; + } + mutex_unlock(&acpi_device_lock); + + return found; +} +EXPORT_SYMBOL(acpi_dev_present); + /* * acpi_backlight= handling, this is done here rather then in video_detect.c * because __setup cannot be used in modules. |