7 files changed, 206 insertions, 44 deletions

diff --git a/Documentation/ABI/testing/sysfs-devices-cache_disable b/Documentation/ABI/testing/sysfs-devices-cache_disable
deleted file mode 100644
index 175bb4f70512..000000000000
--- a/Documentation/ABI/testing/sysfs-devices-cache_disable
+++ /dev/null
@@ -1,18 +0,0 @@
-What:      /sys/devices/system/cpu/cpu*/cache/index*/cache_disable_X
-Date:      August 2008
-KernelVersion:  2.6.27
-Contact:        mark.langsdorf@amd.com
-Description:    These files exist in every cpu's cache index directories.
-                There are currently 2 cache_disable_# files in each
-                directory.  Reading from these files on a supported
-                processor will return that cache disable index value
-                for that processor and node.  Writing to one of these
-                files will cause the specificed cache index to be disabled.
-
-                Currently, only AMD Family 10h Processors support cache index
-                disable, and only for their L3 caches.  See the BIOS and
-                Kernel Developer's Guide at
-                http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/31116-Public-GH-BKDG_3.20_2-4-09.pdf
-                for formatting information and other details on the
-                cache index disable.
-Users:    joachim.deguara@amd.com
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
new file mode 100644
index 000000000000..a703b9e9aeb9
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -0,0 +1,156 @@
+What:           /sys/devices/system/cpu/
+Date:           pre-git history
+Contact:        Linux kernel mailing list <linux-kernel@vger.kernel.org>
+Description:
+                A collection of both global and individual CPU attributes
+
+                Individual CPU attributes are contained in subdirectories
+                named by the kernel's logical CPU number, e.g.:
+
+                /sys/devices/system/cpu/cpu#/
+
+What:           /sys/devices/system/cpu/sched_mc_power_savings
+                /sys/devices/system/cpu/sched_smt_power_savings
+Date:           June 2006
+Contact:        Linux kernel mailing list <linux-kernel@vger.kernel.org>
+Description:    Discover and adjust the kernel's multi-core scheduler support.
+
+                Possible values are:
+
+                0 - No power saving load balance (default value)
+                1 - Fill one thread/core/package first for long running threads
+                2 - Also bias task wakeups to semi-idle cpu package for power
+                    savings
+
+                sched_mc_power_savings is dependent upon SCHED_MC, which is
+                itself architecture dependent.
+
+                sched_smt_power_savings is dependent upon SCHED_SMT, which
+                is itself architecture dependent.
+
+                The two files are independent of each other. It is possible
+                that one file may be present without the other.
+
+                Introduced by git commit 5c45bf27.
+
+
+What:           /sys/devices/system/cpu/kernel_max
+                /sys/devices/system/cpu/offline
+                /sys/devices/system/cpu/online
+                /sys/devices/system/cpu/possible
+                /sys/devices/system/cpu/present
+Date:           December 2008
+Contact:        Linux kernel mailing list <linux-kernel@vger.kernel.org>
+Description:    CPU topology files that describe kernel limits related to
+                hotplug. Briefly:
+
+                kernel_max: the maximum cpu index allowed by the kernel
+                configuration.
+
+                offline: cpus that are not online because they have been
+                HOTPLUGGED off or exceed the limit of cpus allowed by the
+                kernel configuration (kernel_max above).
+
+                online: cpus that are online and being scheduled.
+
+                possible: cpus that have been allocated resources and can be
+                brought online if they are present.
+
+                present: cpus that have been identified as being present in
+                the system.
+
+                See Documentation/cputopology.txt for more information.
+
+
+
+What:           /sys/devices/system/cpu/cpu#/node
+Date:           October 2009
+Contact:        Linux memory management mailing list <linux-mm@kvack.org>
+Description:    Discover NUMA node a CPU belongs to
+
+                When CONFIG_NUMA is enabled, a symbolic link that points
+                to the corresponding NUMA node directory.
+
+                For example, the following symlink is created for cpu42
+                in NUMA node 2:
+
+                /sys/devices/system/cpu/cpu42/node2 -> ../../node/node2
+
+
+What:           /sys/devices/system/cpu/cpu#/topology/core_id
+                /sys/devices/system/cpu/cpu#/topology/core_siblings
+                /sys/devices/system/cpu/cpu#/topology/core_siblings_list
+                /sys/devices/system/cpu/cpu#/topology/physical_package_id
+                /sys/devices/system/cpu/cpu#/topology/thread_siblings
+                /sys/devices/system/cpu/cpu#/topology/thread_siblings_list
+Date:           December 2008
+Contact:        Linux kernel mailing list <linux-kernel@vger.kernel.org>
+Description:    CPU topology files that describe a logical CPU's relationship
+                to other cores and threads in the same physical package.
+
+                One cpu# directory is created per logical CPU in the system,
+                e.g. /sys/devices/system/cpu/cpu42/.
+
+                Briefly, the files above are:
+
+                core_id: the CPU core ID of cpu#. Typically it is the
+                hardware platform's identifier (rather than the kernel's).
+                The actual value is architecture and platform dependent.
+
+                core_siblings: internal kernel map of cpu#'s hardware threads
+                within the same physical_package_id.
+
+                core_siblings_list: human-readable list of the logical CPU
+                numbers within the same physical_package_id as cpu#.
+
+                physical_package_id: physical package id of cpu#. Typically
+                corresponds to a physical socket number, but the actual value
+                is architecture and platform dependent.
+
+                thread_siblings: internel kernel map of cpu#'s hardware
+                threads within the same core as cpu#
+
+                thread_siblings_list: human-readable list of cpu#'s hardware
+                threads within the same core as cpu#
+
+                See Documentation/cputopology.txt for more information.
+
+
+What:           /sys/devices/system/cpu/cpuidle/current_driver
+                /sys/devices/system/cpu/cpuidle/current_governer_ro
+Date:           September 2007
+Contact:        Linux kernel mailing list <linux-kernel@vger.kernel.org>
+Description:    Discover cpuidle policy and mechanism
+
+                Various CPUs today support multiple idle levels that are
+                differentiated by varying exit latencies and power
+                consumption during idle.
+
+                Idle policy (governor) is differentiated from idle mechanism
+                (driver)
+
+                current_driver: displays current idle mechanism
+
+                current_governor_ro: displays current idle policy
+
+                See files in Documentation/cpuidle/ for more information.
+
+
+What:      /sys/devices/system/cpu/cpu*/cache/index*/cache_disable_X
+Date:      August 2008
+KernelVersion:  2.6.27
+Contact:        mark.langsdorf@amd.com
+Description:    These files exist in every cpu's cache index directories.
+                There are currently 2 cache_disable_# files in each
+                directory.  Reading from these files on a supported
+                processor will return that cache disable index value
+                for that processor and node.  Writing to one of these
+                files will cause the specificed cache index to be disabled.
+
+                Currently, only AMD Family 10h Processors support cache index
+                disable, and only for their L3 caches.  See the BIOS and
+                Kernel Developer's Guide at
+                http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/31116-Public-GH-BKDG_3.20_2-4-09.pdf
+                for formatting information and other details on the
+                cache index disable.
+Users:    joachim.deguara@amd.com
diff --git a/Documentation/cputopology.txt b/Documentation/cputopology.txt
index b41f3e58aefa..f1c5c4bccd3e 100644
--- a/Documentation/cputopology.txt
+++ b/Documentation/cputopology.txt
@@ -1,15 +1,28 @@
 
-Export cpu topology info via sysfs. Items (attributes) are similar
+Export CPU topology info via sysfs. Items (attributes) are similar
 to /proc/cpuinfo.
 
 1) /sys/devices/system/cpu/cpuX/topology/physical_package_id:
-represent the physical package id of  cpu X;
+
+        physical package id of cpuX. Typically corresponds to a physical
+        socket number, but the actual value is architecture and platform
+        dependent.
+
 2) /sys/devices/system/cpu/cpuX/topology/core_id:
-represent the cpu core id to cpu X;
+
+        the CPU core ID of cpuX. Typically it is the hardware platform's
+        identifier (rather than the kernel's).  The actual value is
+        architecture and platform dependent.
+
 3) /sys/devices/system/cpu/cpuX/topology/thread_siblings:
-represent the thread siblings to cpu X in the same core;
+
+        internel kernel map of cpuX's hardware threads within the same
+        core as cpuX
+
 4) /sys/devices/system/cpu/cpuX/topology/core_siblings:
-represent the thread siblings to cpu X in the same physical package;
+
+        internal kernel map of cpuX's hardware threads within the same
+        physical_package_id.
 
 To implement it in an architecture-neutral way, a new source file,
 drivers/base/topology.c, is to export the 4 attributes.
@@ -32,32 +45,32 @@ not defined by include/asm-XXX/topology.h:
 3) thread_siblings: just the given CPU
 4) core_siblings: just the given CPU
 
-Additionally, cpu topology information is provided under
+Additionally, CPU topology information is provided under
 /sys/devices/system/cpu and includes these files.  The internal
 source for the output is in brackets ("[]").
 
-    kernel_max: the maximum cpu index allowed by the kernel configuration.
+    kernel_max: the maximum CPU index allowed by the kernel configuration.
                 [NR_CPUS-1]
 
-    offline:    cpus that are not online because they have been
+    offline:    CPUs that are not online because they have been
                 HOTPLUGGED off (see cpu-hotplug.txt) or exceed the limit
-                of cpus allowed by the kernel configuration (kernel_max
+                of CPUs allowed by the kernel configuration (kernel_max
                 above). [~cpu_online_mask + cpus >= NR_CPUS]
 
-    online:     cpus that are online and being scheduled [cpu_online_mask]
+    online:     CPUs that are online and being scheduled [cpu_online_mask]
 
-    possible:   cpus that have been allocated resources and can be
+    possible:   CPUs that have been allocated resources and can be
                 brought online if they are present. [cpu_possible_mask]
 
-    present:    cpus that have been identified as being present in the
+    present:    CPUs that have been identified as being present in the
                 system. [cpu_present_mask]
 
 The format for the above output is compatible with cpulist_parse()
 [see <linux/cpumask.h>].  Some examples follow.
 
-In this example, there are 64 cpus in the system but cpus 32-63 exceed
+In this example, there are 64 CPUs in the system but cpus 32-63 exceed
 the kernel max which is limited to 0..31 by the NR_CPUS config option
-being 32.  Note also that cpus 2 and 4-31 are not online but could be
+being 32.  Note also that CPUs 2 and 4-31 are not online but could be
 brought online as they are both present and possible.
 
      kernel_max: 31
@@ -67,8 +80,8 @@ brought online as they are both present and possible.
         present: 0-31
 
 In this example, the NR_CPUS config option is 128, but the kernel was
-started with possible_cpus=144.  There are 4 cpus in the system and cpu2
-was manually taken offline (and is the only cpu that can be brought
+started with possible_cpus=144.  There are 4 CPUs in the system and cpu2
+was manually taken offline (and is the only CPU that can be brought
 online.)
 
      kernel_max: 127
@@ -78,4 +91,4 @@ online.)
         present: 0-3
 
 See cpu-hotplug.txt for the possible_cpus=NUM kernel start parameter
-as well as more information on the various cpumask's.
+as well as more information on the various cpumasks.
diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index 973bf2ad4e0d..63c143e54a57 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -689,15 +689,19 @@ int bus_add_driver(struct device_driver *drv)
                 printk(KERN_ERR "%s: driver_add_attrs(%s) failed\n",
                         __func__, drv->name);
         }
-        error = add_bind_files(drv);
-        if (error) {
-                /* Ditto */
-                printk(KERN_ERR "%s: add_bind_files(%s) failed\n",
-                        __func__, drv->name);
+
+        if (!drv->suppress_bind_attrs) {
+                error = add_bind_files(drv);
+                if (error) {
+                        /* Ditto */
+                        printk(KERN_ERR "%s: add_bind_files(%s) failed\n",
+                                __func__, drv->name);
+                }
         }
 
         kobject_uevent(&priv->kobj, KOBJ_ADD);
         return 0;
+
 out_unregister:
         kfree(drv->p);
         drv->p = NULL;
@@ -720,7 +724,8 @@ void bus_remove_driver(struct device_driver *drv)
         if (!drv->bus)
                 return;
 
-        remove_bind_files(drv);
+        if (!drv->suppress_bind_attrs)
+                remove_bind_files(drv);
         driver_remove_attrs(drv->bus, drv);
         driver_remove_file(drv, &driver_attr_uevent);
         klist_remove(&drv->p->knode_bus);
diff --git a/drivers/base/driver.c b/drivers/base/driver.c
index ed2ebd3c287d..f367885a7646 100644
--- a/drivers/base/driver.c
+++ b/drivers/base/driver.c
@@ -236,7 +236,7 @@ int driver_register(struct device_driver *drv)
                 put_driver(other);
                 printk(KERN_ERR "Error: Driver '%s' is already registered, "
                         "aborting...\n", drv->name);
-                return -EEXIST;
+                return -EBUSY;
         }
 
         ret = bus_add_driver(drv);
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index ed156a13aa40..4fa954b07ac4 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -521,11 +521,15 @@ int __init_or_module platform_driver_probe(struct platform_driver *drv,
 {
         int retval, code;
 
+        /* make sure driver won't have bind/unbind attributes */
+        drv->driver.suppress_bind_attrs = true;
+
         /* temporary section violation during probe() */
         drv->probe = probe;
         retval = code = platform_driver_register(drv);
 
-        /* Fixup that section violation, being paranoid about code scanning
+        /*
+         * Fixup that section violation, being paranoid about code scanning
          * the list of drivers in order to probe new devices.  Check to see
          * if the probe was successful, and make sure any forced probes of
          * new devices fail.
diff --git a/include/linux/device.h b/include/linux/device.h
index aca31bf7d8ed..2ea3e4921812 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -124,7 +124,9 @@ struct device_driver {
         struct bus_type         *bus;
 
         struct module           *owner;
-        const char              *mod_name;      /* used for built-in modules */
+        const char              *mod_name;      /* used for built-in modules */
+
+        bool suppress_bind_attrs;       /* disables bind/unbind via sysfs */
 
         int (*probe) (struct device *dev);
         int (*remove) (struct device *dev);