From 20f97caf1120bd02e8ff4adbad3b44b63626feb5 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 13 Oct 2017 15:27:24 +0200 Subject: PM / QoS: Drop PM_QOS_FLAG_REMOTE_WAKEUP The PM QoS flag PM_QOS_FLAG_REMOTE_WAKEUP is not used consistently and the vast majority of code simply assumes that remote wakeup should be enabled for devices in runtime suspend if they can generate wakeup signals, so drop it. Signed-off-by: Rafael J. Wysocki Acked-by: Ulf Hansson Reviewed-by: Mika Westerberg --- Documentation/ABI/testing/sysfs-devices-power | 16 ---------------- 1 file changed, 16 deletions(-) (limited to 'Documentation/ABI') diff --git a/Documentation/ABI/testing/sysfs-devices-power b/Documentation/ABI/testing/sysfs-devices-power index 676fdf5f2a99..f4b24c327665 100644 --- a/Documentation/ABI/testing/sysfs-devices-power +++ b/Documentation/ABI/testing/sysfs-devices-power @@ -258,19 +258,3 @@ Description: This attribute has no effect on system-wide suspend/resume and hibernation. - -What: /sys/devices/.../power/pm_qos_remote_wakeup -Date: September 2012 -Contact: Rafael J. Wysocki -Description: - The /sys/devices/.../power/pm_qos_remote_wakeup attribute - is used for manipulating the PM QoS "remote wakeup required" - flag. If set, this flag indicates to the kernel that the - device is a source of user events that have to be signaled from - its low-power states. - - Not all drivers support this attribute. If it isn't supported, - it is not present. - - This attribute has no effect on system-wide suspend/resume and - hibernation. -- cgit v1.2.3 From 0759e80b84e34a84e7e46e2b1adb528c83d84a47 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 7 Nov 2017 11:33:49 +0100 Subject: PM / QoS: Fix device resume latency framework The special value of 0 for device resume latency PM QoS means "no restriction", but there are two problems with that. First, device resume latency PM QoS requests with 0 as the value are always put in front of requests with positive values in the priority lists used internally by the PM QoS framework, causing 0 to be chosen as an effective constraint value. However, that 0 is then interpreted as "no restriction" effectively overriding the other requests with specific restrictions which is incorrect. Second, the users of device resume latency PM QoS have no way to specify that *any* resume latency at all should be avoided, which is an artificial limitation in general. To address these issues, modify device resume latency PM QoS to use S32_MAX as the "no constraint" value and 0 as the "no latency at all" one and rework its users (the cpuidle menu governor, the genpd QoS governor and the runtime PM framework) to follow these changes. Also add a special "n/a" value to the corresponding user space I/F to allow user space to indicate that it cannot accept any resume latencies at all for the given device. Fixes: 85dc0b8a4019 (PM / QoS: Make it possible to expose PM QoS latency constraints) Link: https://bugzilla.kernel.org/show_bug.cgi?id=197323 Reported-by: Reinette Chatre Signed-off-by: Rafael J. Wysocki Tested-by: Reinette Chatre Tested-by: Geert Uytterhoeven Tested-by: Tero Kristo Reviewed-by: Ramesh Thomas --- Documentation/ABI/testing/sysfs-devices-power | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'Documentation/ABI') diff --git a/Documentation/ABI/testing/sysfs-devices-power b/Documentation/ABI/testing/sysfs-devices-power index f4b24c327665..80a00f7b6667 100644 --- a/Documentation/ABI/testing/sysfs-devices-power +++ b/Documentation/ABI/testing/sysfs-devices-power @@ -211,7 +211,9 @@ Description: device, after it has been suspended at run time, from a resume request to the moment the device will be ready to process I/O, in microseconds. If it is equal to 0, however, this means that - the PM QoS resume latency may be arbitrary. + the PM QoS resume latency may be arbitrary and the special value + "n/a" means that user space cannot accept any resume latency at + all for the given device. Not all drivers support this attribute. If it isn't supported, it is not present. -- cgit v1.2.3