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author | Daniel Scally <djrscally@gmail.com> | 2022-09-22 00:04:35 +0100 |
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committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2022-09-24 19:12:32 +0200 |
commit | cca8a7efea6402f463239a1bb337d01b0cad7b2e (patch) | |
tree | eb7ce6efbf056a9a0703df30358d8c15f60390b4 /drivers/acpi/scan.c | |
parent | 98378956a407392109817278c6edd464252c7a83 (diff) | |
download | linux-cca8a7efea6402f463239a1bb337d01b0cad7b2e.tar.gz linux-cca8a7efea6402f463239a1bb337d01b0cad7b2e.tar.bz2 linux-cca8a7efea6402f463239a1bb337d01b0cad7b2e.zip |
ACPI: scan: Add acpi_dev_get_next_consumer_dev()
In commit b83e2b306736 ("ACPI: scan: Add function to fetch dependent
of ACPI device") we added a means of fetching the first device to
declare itself dependent on another ACPI device in the _DEP method.
One assumption in that patch was that there would only be a single
consuming device, but this has not held.
Replace that function with a new function that fetches the next consumer
of a supplier device. Where no "previous" consumer is passed in, it
behaves identically to the original function.
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Daniel Scally <djrscally@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/scan.c')
-rw-r--r-- | drivers/acpi/scan.c | 40 |
1 files changed, 30 insertions, 10 deletions
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index f6b9ea937de1..d0277427e7ee 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -2235,9 +2235,22 @@ ok: return 0; } -static int acpi_dev_get_first_consumer_dev_cb(struct acpi_dep_data *dep, void *data) +static int acpi_dev_get_next_consumer_dev_cb(struct acpi_dep_data *dep, void *data) { - struct acpi_device *adev; + struct acpi_device **adev_p = data; + struct acpi_device *adev = *adev_p; + + /* + * If we're passed a 'previous' consumer device then we need to skip + * any consumers until we meet the previous one, and then NULL @data + * so the next one can be returned. + */ + if (adev) { + if (dep->consumer == adev->handle) + *adev_p = NULL; + + return 0; + } adev = acpi_get_acpi_dev(dep->consumer); if (adev) { @@ -2368,25 +2381,32 @@ bool acpi_dev_ready_for_enumeration(const struct acpi_device *device) EXPORT_SYMBOL_GPL(acpi_dev_ready_for_enumeration); /** - * acpi_dev_get_first_consumer_dev - Return ACPI device dependent on @supplier + * acpi_dev_get_next_consumer_dev - Return the next adev dependent on @supplier * @supplier: Pointer to the dependee device + * @start: Pointer to the current dependent device * - * Returns the first &struct acpi_device which declares itself dependent on + * Returns the next &struct acpi_device which declares itself dependent on * @supplier via the _DEP buffer, parsed from the acpi_dep_list. * - * The caller is responsible for putting the reference to adev when it is no - * longer needed. + * If the returned adev is not passed as @start to this function, the caller is + * responsible for putting the reference to adev when it is no longer needed. */ -struct acpi_device *acpi_dev_get_first_consumer_dev(struct acpi_device *supplier) +struct acpi_device *acpi_dev_get_next_consumer_dev(struct acpi_device *supplier, + struct acpi_device *start) { - struct acpi_device *adev = NULL; + struct acpi_device *adev = start; acpi_walk_dep_device_list(supplier->handle, - acpi_dev_get_first_consumer_dev_cb, &adev); + acpi_dev_get_next_consumer_dev_cb, &adev); + + acpi_dev_put(start); + + if (adev == start) + return NULL; return adev; } -EXPORT_SYMBOL_GPL(acpi_dev_get_first_consumer_dev); +EXPORT_SYMBOL_GPL(acpi_dev_get_next_consumer_dev); /** * acpi_bus_scan - Add ACPI device node objects in a given namespace scope. |