diff options
| -rw-r--r-- | drivers/acpi/utils.c | 66 | ||||
| -rw-r--r-- | include/acpi/acpi_bus.h | 1 | ||||
| -rw-r--r-- | include/linux/acpi.h | 5 |
3 files changed, 72 insertions, 0 deletions
diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c index 22c09952e177..27d0dcfcf47d 100644 --- a/drivers/acpi/utils.c +++ b/drivers/acpi/utils.c @@ -736,6 +736,72 @@ bool acpi_dev_found(const char *hid) } EXPORT_SYMBOL(acpi_dev_found); +struct acpi_dev_present_info { + struct acpi_device_id hid[2]; + const char *uid; + s64 hrv; +}; + +static int acpi_dev_present_cb(struct device *dev, void *data) +{ + struct acpi_device *adev = to_acpi_device(dev); + struct acpi_dev_present_info *match = data; + unsigned long long hrv; + acpi_status status; + + if (acpi_match_device_ids(adev, match->hid)) + return 0; + + if (match->uid && (!adev->pnp.unique_id || + strcmp(adev->pnp.unique_id, match->uid))) + return 0; + + if (match->hrv == -1) + return 1; + + status = acpi_evaluate_integer(adev->handle, "_HRV", NULL, &hrv); + if (ACPI_FAILURE(status)) + return 0; + + return hrv == match->hrv; +} + +/** + * acpi_dev_present - Detect that a given ACPI device is present + * @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 %true if a matching device was present at the moment of invocation. + * Note that if the device is pluggable, it may since have disappeared. + * + * Note that unlike acpi_dev_found() this function checks the status + * of the device. So for devices which are present in the dsdt, but + * which are disabled (their _STA callback returns 0) this function + * will return false. + * + * 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, const char *uid, s64 hrv) +{ + struct acpi_dev_present_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_present_cb); + + return !!dev; +} +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. diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index ef0ae8aaa567..b53c058e7009 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -88,6 +88,7 @@ acpi_evaluate_dsm_typed(acpi_handle handle, const u8 *uuid, u64 rev, u64 func, } bool acpi_dev_found(const char *hid); +bool acpi_dev_present(const char *hid, const char *uid, s64 hrv); #ifdef CONFIG_ACPI diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 9b05886f9773..841a8dc55ade 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -611,6 +611,11 @@ static inline bool acpi_dev_found(const char *hid) return false; } +static inline bool acpi_dev_present(const char *hid, const char *uid, s64 hrv) +{ + return false; +} + static inline bool is_acpi_node(struct fwnode_handle *fwnode) { return false; |