Merge tag 'pm+acpi-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI updates from Rafael Wysocki:
 "These are mostly fixes and cleanups all over, although there are a few
  items that sort of fall into the new feature category.

  First off, we have new callbacks for PM domains that should help us to
  handle some issues related to device initialization in a better way.

  There also is some consolidation in the unified device properties API
  area allowing us to use that inferface for accessing data coming from
  platform initialization code in addition to firmware-provided data.

  We have some new device/CPU IDs in a few drivers, support for new
  chips and a new cpufreq driver too.

  Specifics:

   - Generic PM domains support update including new PM domain callbacks
     to handle device initialization better (Russell King, Rafael J
     Wysocki, Kevin Hilman)

   - Unified device properties API update including a new mechanism for
     accessing data provided by platform initialization code (Rafael J
     Wysocki, Adrian Hunter)

   - ARM cpuidle update including ARM32/ARM64 handling consolidation
     (Daniel Lezcano)

   - intel_idle update including support for the Silvermont Core in the
     Baytrail SOC and for the Airmont Core in the Cherrytrail and
     Braswell SOCs (Len Brown, Mathias Krause)

   - New cpufreq driver for Hisilicon ACPU (Leo Yan)

   - intel_pstate update including support for the Knights Landing chip
     (Dasaratharaman Chandramouli, Kristen Carlson Accardi)

   - QorIQ cpufreq driver update (Tang Yuantian, Arnd Bergmann)

   - powernv cpufreq driver update (Shilpasri G Bhat)

   - devfreq update including Tegra support changes (Tomeu Vizoso,
     MyungJoo Ham, Chanwoo Choi)

   - powercap RAPL (Running-Average Power Limit) driver update including
     support for Intel Broadwell server chips (Jacob Pan, Mathias Krause)

   - ACPI device enumeration update related to the handling of the
     special PRP0001 device ID allowing DT-style 'compatible' property
     to be used for ACPI device identification (Rafael J Wysocki)

   - ACPI EC driver update including limited _DEP support (Lan Tianyu,
     Lv Zheng)

   - ACPI backlight driver update including a new mechanism to allow
     native backlight handling to be forced on non-Windows 8 systems and
     a new quirk for Lenovo Ideapad Z570 (Aaron Lu, Hans de Goede)

   - New Windows Vista compatibility quirk for Sony VGN-SR19XN (Chen Yu)

   - Assorted ACPI fixes and cleanups (Aaron Lu, Martin Kepplinger,
     Masanari Iida, Mika Westerberg, Nan Li, Rafael J Wysocki)

   - Fixes related to suspend-to-idle for the iTCO watchdog driver and
     the ACPI core system suspend/resume code (Rafael J Wysocki, Chen Yu)

   - PM tracing support for the suspend phase of system suspend/resume
     transitions (Zhonghui Fu)

   - Configurable delay for the system suspend/resume testing facility
     (Brian Norris)

   - PNP subsystem cleanups (Peter Huewe, Rafael J Wysocki)"

* tag 'pm+acpi-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (74 commits)
  ACPI / scan: Fix NULL pointer dereference in acpi_companion_match()
  ACPI / scan: Rework modalias creation when "compatible" is present
  intel_idle: mark cpu id array as __initconst
  powercap / RAPL: mark rapl_ids array as __initconst
  powercap / RAPL: add ID for Broadwell server
  intel_pstate: Knights Landing support
  intel_pstate: remove MSR test
  cpufreq: fix qoriq uniprocessor build
  ACPI / scan: Take the PRP0001 position in the list of IDs into account
  ACPI / scan: Simplify acpi_match_device()
  ACPI / scan: Generalize of_compatible matching
  device property: Introduce firmware node type for platform data
  device property: Make it possible to use secondary firmware nodes
  PM / watchdog: iTCO: stop watchdog during system suspend
  cpufreq: hisilicon: add acpu driver
  ACPI / EC: Call acpi_walk_dep_device_list() after installing EC opregion handler
  cpufreq: powernv: Report cpu frequency throttling
  intel_idle: Add support for the Airmont Core in the Cherrytrail and Braswell SOCs
  intel_idle: Update support for Silvermont Core in Baytrail SOC
  PM / devfreq: tegra: Register governor on module init
  ...

1 files changed, 46 insertions, 18 deletions

diff --git a/drivers/pnp/core.c b/drivers/pnp/core.c
index cb6ce42f8e77..b54620e53830 100644
--- a/drivers/pnp/core.c
+++ b/drivers/pnp/core.c
@@ -9,6 +9,7 @@
 #include <linux/list.h>
 #include <linux/device.h>
 #include <linux/module.h>
+#include <linux/mutex.h>
 #include <linux/init.h>
 #include <linux/string.h>
 #include <linux/slab.h>
@@ -19,7 +20,7 @@
 
 static LIST_HEAD(pnp_protocols);
 LIST_HEAD(pnp_global);
-DEFINE_SPINLOCK(pnp_lock);
+DEFINE_MUTEX(pnp_lock);
 
 /*
  * ACPI or PNPBIOS should tell us about all platform devices, so we can
@@ -41,6 +42,13 @@ void *pnp_alloc(long size)
         return result;
 }
 
+static void pnp_remove_protocol(struct pnp_protocol *protocol)
+{
+        mutex_lock(&pnp_lock);
+        list_del(&protocol->protocol_list);
+        mutex_unlock(&pnp_lock);
+}
+
 /**
  * pnp_protocol_register - adds a pnp protocol to the pnp layer
  * @protocol: pointer to the corresponding pnp_protocol structure
@@ -49,13 +57,14 @@ void *pnp_alloc(long size)
  */
 int pnp_register_protocol(struct pnp_protocol *protocol)
 {
-        int nodenum;
         struct list_head *pos;
+        int nodenum, ret;
 
         INIT_LIST_HEAD(&protocol->devices);
         INIT_LIST_HEAD(&protocol->cards);
         nodenum = 0;
-        spin_lock(&pnp_lock);
+
+        mutex_lock(&pnp_lock);
 
         /* assign the lowest unused number */
         list_for_each(pos, &pnp_protocols) {
@@ -66,12 +75,18 @@ int pnp_register_protocol(struct pnp_protocol *protocol)
                 }
         }
 
-        list_add_tail(&protocol->protocol_list, &pnp_protocols);
-        spin_unlock(&pnp_lock);
-
         protocol->number = nodenum;
         dev_set_name(&protocol->dev, "pnp%d", nodenum);
-        return device_register(&protocol->dev);
+
+        list_add_tail(&protocol->protocol_list, &pnp_protocols);
+
+        mutex_unlock(&pnp_lock);
+
+        ret = device_register(&protocol->dev);
+        if (ret)
+                pnp_remove_protocol(protocol);
+
+        return ret;
 }
 
 /**
@@ -80,9 +95,7 @@ int pnp_register_protocol(struct pnp_protocol *protocol)
  */
 void pnp_unregister_protocol(struct pnp_protocol *protocol)
 {
-        spin_lock(&pnp_lock);
-        list_del(&protocol->protocol_list);
-        spin_unlock(&pnp_lock);
+        pnp_remove_protocol(protocol);
         device_unregister(&protocol->dev);
 }
 
@@ -157,18 +170,36 @@ struct pnp_dev *pnp_alloc_dev(struct pnp_protocol *protocol, int id,
         return dev;
 }
 
+static void pnp_delist_device(struct pnp_dev *dev)
+{
+        mutex_lock(&pnp_lock);
+        list_del(&dev->global_list);
+        list_del(&dev->protocol_list);
+        mutex_unlock(&pnp_lock);
+}
+
 int __pnp_add_device(struct pnp_dev *dev)
 {
+        int ret;
+
         pnp_fixup_device(dev);
         dev->status = PNP_READY;
-        spin_lock(&pnp_lock);
+
+        mutex_lock(&pnp_lock);
+
         list_add_tail(&dev->global_list, &pnp_global);
         list_add_tail(&dev->protocol_list, &dev->protocol->devices);
-        spin_unlock(&pnp_lock);
-        if (dev->protocol->can_wakeup)
+
+        mutex_unlock(&pnp_lock);
+
+        ret = device_register(&dev->dev);
+        if (ret)
+                pnp_delist_device(dev);
+        else if (dev->protocol->can_wakeup)
                 device_set_wakeup_capable(&dev->dev,
                                 dev->protocol->can_wakeup(dev));
-        return device_register(&dev->dev);
+
+        return ret;
 }
 
 /*
@@ -203,10 +234,7 @@ int pnp_add_device(struct pnp_dev *dev)
 
 void __pnp_remove_device(struct pnp_dev *dev)
 {
-        spin_lock(&pnp_lock);
-        list_del(&dev->global_list);
-        list_del(&dev->protocol_list);
-        spin_unlock(&pnp_lock);
+        pnp_delist_device(dev);
         device_unregister(&dev->dev);
 }