diff options
Diffstat (limited to 'Documentation/driver-api/device_link.rst')
-rw-r--r-- | Documentation/driver-api/device_link.rst | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/Documentation/driver-api/device_link.rst b/Documentation/driver-api/device_link.rst index 5f5713448703..70e328e16aad 100644 --- a/Documentation/driver-api/device_link.rst +++ b/Documentation/driver-api/device_link.rst @@ -1,3 +1,6 @@ +.. |struct dev_pm_domain| replace:: :c:type:`struct dev_pm_domain <dev_pm_domain>` +.. |struct generic_pm_domain| replace:: :c:type:`struct generic_pm_domain <generic_pm_domain>` + ============ Device links ============ @@ -120,12 +123,11 @@ Examples is the same as if the MMU was the parent of the master device. The fact that both devices share the same power domain would normally - suggest usage of a :c:type:`struct dev_pm_domain` or :c:type:`struct - generic_pm_domain`, however these are not independent devices that - happen to share a power switch, but rather the MMU device serves the - busmaster device and is useless without it. A device link creates a - synthetic hierarchical relationship between the devices and is thus - more apt. + suggest usage of a |struct dev_pm_domain| or |struct generic_pm_domain|, + however these are not independent devices that happen to share a power + switch, but rather the MMU device serves the busmaster device and is + useless without it. A device link creates a synthetic hierarchical + relationship between the devices and is thus more apt. * A Thunderbolt host controller comprises a number of PCIe hotplug ports and an NHI device to manage the PCIe switch. On resume from system sleep, @@ -157,7 +159,7 @@ Examples Alternatives ============ -* A :c:type:`struct dev_pm_domain` can be used to override the bus, +* A |struct dev_pm_domain| can be used to override the bus, class or device type callbacks. It is intended for devices sharing a single on/off switch, however it does not guarantee a specific suspend/resume ordering, this needs to be implemented separately. @@ -166,7 +168,7 @@ Alternatives suspended. Furthermore it cannot be used to enforce a specific shutdown ordering or a driver presence dependency. -* A :c:type:`struct generic_pm_domain` is a lot more heavyweight than a +* A |struct generic_pm_domain| is a lot more heavyweight than a device link and does not allow for shutdown ordering or driver presence dependencies. It also cannot be used on ACPI systems. |