diff options
author | Takashi Iwai <tiwai@suse.de> | 2009-12-25 08:15:31 -0500 |
---|---|---|
committer | Takashi Iwai <tiwai@suse.de> | 2009-12-25 08:15:31 -0500 |
commit | 52e04ea89da57274f0313d2bd73ba02f686cfdeb (patch) | |
tree | 6ce5d086bcaea4cb534b3fcf6ba736eb48d582a4 /Documentation | |
parent | 41116e926cb92292fa4fcbe888ae8133fa0038e6 (diff) | |
parent | 8b90ca08821fee79e181bfcbc3bbd41ef5637136 (diff) |
Merge branch 'fix/misc' into topic/misc
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/ABI/testing/sysfs-bus-usb | 18 | ||||
-rw-r--r-- | Documentation/cpu-hotplug.txt | 49 | ||||
-rw-r--r-- | Documentation/dontdiff | 1 | ||||
-rw-r--r-- | Documentation/driver-model/driver.txt | 4 | ||||
-rw-r--r-- | Documentation/filesystems/sysfs.txt | 12 | ||||
-rw-r--r-- | Documentation/hwmon/k10temp | 60 | ||||
-rw-r--r-- | Documentation/kbuild/kbuild.txt | 14 | ||||
-rw-r--r-- | Documentation/kbuild/kconfig.txt | 8 | ||||
-rw-r--r-- | Documentation/power/runtime_pm.txt | 223 | ||||
-rw-r--r-- | Documentation/powerpc/dts-bindings/fsl/mpic.txt | 42 | ||||
-rw-r--r-- | Documentation/sound/alsa/HD-Audio-Models.txt | 1 | ||||
-rw-r--r-- | Documentation/stable_kernel_rules.txt | 24 | ||||
-rw-r--r-- | Documentation/trace/events-kmem.txt | 14 | ||||
-rw-r--r-- | Documentation/usb/power-management.txt | 41 |
14 files changed, 341 insertions, 170 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb index deb6b489e4e5..a07c0f366f91 100644 --- a/Documentation/ABI/testing/sysfs-bus-usb +++ b/Documentation/ABI/testing/sysfs-bus-usb | |||
@@ -21,25 +21,27 @@ Contact: Alan Stern <stern@rowland.harvard.edu> | |||
21 | Description: | 21 | Description: |
22 | Each USB device directory will contain a file named | 22 | Each USB device directory will contain a file named |
23 | power/level. This file holds a power-level setting for | 23 | power/level. This file holds a power-level setting for |
24 | the device, one of "on", "auto", or "suspend". | 24 | the device, either "on" or "auto". |
25 | 25 | ||
26 | "on" means that the device is not allowed to autosuspend, | 26 | "on" means that the device is not allowed to autosuspend, |
27 | although normal suspends for system sleep will still | 27 | although normal suspends for system sleep will still |
28 | be honored. "auto" means the device will autosuspend | 28 | be honored. "auto" means the device will autosuspend |
29 | and autoresume in the usual manner, according to the | 29 | and autoresume in the usual manner, according to the |
30 | capabilities of its driver. "suspend" means the device | 30 | capabilities of its driver. |
31 | is forced into a suspended state and it will not autoresume | ||
32 | in response to I/O requests. However remote-wakeup requests | ||
33 | from the device may still be enabled (the remote-wakeup | ||
34 | setting is controlled separately by the power/wakeup | ||
35 | attribute). | ||
36 | 31 | ||
37 | During normal use, devices should be left in the "auto" | 32 | During normal use, devices should be left in the "auto" |
38 | level. The other levels are meant for administrative uses. | 33 | level. The "on" level is meant for administrative uses. |
39 | If you want to suspend a device immediately but leave it | 34 | If you want to suspend a device immediately but leave it |
40 | free to wake up in response to I/O requests, you should | 35 | free to wake up in response to I/O requests, you should |
41 | write "0" to power/autosuspend. | 36 | write "0" to power/autosuspend. |
42 | 37 | ||
38 | Device not capable of proper suspend and resume should be | ||
39 | left in the "on" level. Although the USB spec requires | ||
40 | devices to support suspend/resume, many of them do not. | ||
41 | In fact so many don't that by default, the USB core | ||
42 | initializes all non-hub devices in the "on" level. Some | ||
43 | drivers may change this setting when they are bound. | ||
44 | |||
43 | What: /sys/bus/usb/devices/.../power/persist | 45 | What: /sys/bus/usb/devices/.../power/persist |
44 | Date: May 2007 | 46 | Date: May 2007 |
45 | KernelVersion: 2.6.23 | 47 | KernelVersion: 2.6.23 |
diff --git a/Documentation/cpu-hotplug.txt b/Documentation/cpu-hotplug.txt index 4d4a644b505e..a99d7031cdf9 100644 --- a/Documentation/cpu-hotplug.txt +++ b/Documentation/cpu-hotplug.txt | |||
@@ -315,41 +315,26 @@ A: The following are what is required for CPU hotplug infrastructure to work | |||
315 | 315 | ||
316 | Q: I need to ensure that a particular cpu is not removed when there is some | 316 | Q: I need to ensure that a particular cpu is not removed when there is some |
317 | work specific to this cpu is in progress. | 317 | work specific to this cpu is in progress. |
318 | A: First switch the current thread context to preferred cpu | 318 | A: There are two ways. If your code can be run in interrupt context, use |
319 | smp_call_function_single(), otherwise use work_on_cpu(). Note that | ||
320 | work_on_cpu() is slow, and can fail due to out of memory: | ||
319 | 321 | ||
320 | int my_func_on_cpu(int cpu) | 322 | int my_func_on_cpu(int cpu) |
321 | { | 323 | { |
322 | cpumask_t saved_mask, new_mask = CPU_MASK_NONE; | 324 | int err; |
323 | int curr_cpu, err = 0; | 325 | get_online_cpus(); |
324 | 326 | if (!cpu_online(cpu)) | |
325 | saved_mask = current->cpus_allowed; | 327 | err = -EINVAL; |
326 | cpu_set(cpu, new_mask); | 328 | else |
327 | err = set_cpus_allowed(current, new_mask); | 329 | #if NEEDS_BLOCKING |
328 | 330 | err = work_on_cpu(cpu, __my_func_on_cpu, NULL); | |
329 | if (err) | 331 | #else |
330 | return err; | 332 | smp_call_function_single(cpu, __my_func_on_cpu, &err, |
331 | 333 | true); | |
332 | /* | 334 | #endif |
333 | * If we got scheduled out just after the return from | 335 | put_online_cpus(); |
334 | * set_cpus_allowed() before running the work, this ensures | 336 | return err; |
335 | * we stay locked. | 337 | } |
336 | */ | ||
337 | curr_cpu = get_cpu(); | ||
338 | |||
339 | if (curr_cpu != cpu) { | ||
340 | err = -EAGAIN; | ||
341 | goto ret; | ||
342 | } else { | ||
343 | /* | ||
344 | * Do work : But cant sleep, since get_cpu() disables preempt | ||
345 | */ | ||
346 | } | ||
347 | ret: | ||
348 | put_cpu(); | ||
349 | set_cpus_allowed(current, saved_mask); | ||
350 | return err; | ||
351 | } | ||
352 | |||
353 | 338 | ||
354 | Q: How do we determine how many CPUs are available for hotplug. | 339 | Q: How do we determine how many CPUs are available for hotplug. |
355 | A: There is no clear spec defined way from ACPI that can give us that | 340 | A: There is no clear spec defined way from ACPI that can give us that |
diff --git a/Documentation/dontdiff b/Documentation/dontdiff index e151b2a36267..3ad6acead949 100644 --- a/Documentation/dontdiff +++ b/Documentation/dontdiff | |||
@@ -103,6 +103,7 @@ gconf | |||
103 | gen-devlist | 103 | gen-devlist |
104 | gen_crc32table | 104 | gen_crc32table |
105 | gen_init_cpio | 105 | gen_init_cpio |
106 | generated | ||
106 | genheaders | 107 | genheaders |
107 | genksyms | 108 | genksyms |
108 | *_gray256.c | 109 | *_gray256.c |
diff --git a/Documentation/driver-model/driver.txt b/Documentation/driver-model/driver.txt index 60120fb3b961..d2cd6fb8ba9e 100644 --- a/Documentation/driver-model/driver.txt +++ b/Documentation/driver-model/driver.txt | |||
@@ -226,5 +226,5 @@ struct driver_attribute driver_attr_debug; | |||
226 | This can then be used to add and remove the attribute from the | 226 | This can then be used to add and remove the attribute from the |
227 | driver's directory using: | 227 | driver's directory using: |
228 | 228 | ||
229 | int driver_create_file(struct device_driver *, struct driver_attribute *); | 229 | int driver_create_file(struct device_driver *, const struct driver_attribute *); |
230 | void driver_remove_file(struct device_driver *, struct driver_attribute *); | 230 | void driver_remove_file(struct device_driver *, const struct driver_attribute *); |
diff --git a/Documentation/filesystems/sysfs.txt b/Documentation/filesystems/sysfs.txt index b245d524d568..931c806642c5 100644 --- a/Documentation/filesystems/sysfs.txt +++ b/Documentation/filesystems/sysfs.txt | |||
@@ -91,8 +91,8 @@ struct device_attribute { | |||
91 | const char *buf, size_t count); | 91 | const char *buf, size_t count); |
92 | }; | 92 | }; |
93 | 93 | ||
94 | int device_create_file(struct device *, struct device_attribute *); | 94 | int device_create_file(struct device *, const struct device_attribute *); |
95 | void device_remove_file(struct device *, struct device_attribute *); | 95 | void device_remove_file(struct device *, const struct device_attribute *); |
96 | 96 | ||
97 | It also defines this helper for defining device attributes: | 97 | It also defines this helper for defining device attributes: |
98 | 98 | ||
@@ -316,8 +316,8 @@ DEVICE_ATTR(_name, _mode, _show, _store); | |||
316 | 316 | ||
317 | Creation/Removal: | 317 | Creation/Removal: |
318 | 318 | ||
319 | int device_create_file(struct device *device, struct device_attribute * attr); | 319 | int device_create_file(struct device *dev, const struct device_attribute * attr); |
320 | void device_remove_file(struct device * dev, struct device_attribute * attr); | 320 | void device_remove_file(struct device *dev, const struct device_attribute * attr); |
321 | 321 | ||
322 | 322 | ||
323 | - bus drivers (include/linux/device.h) | 323 | - bus drivers (include/linux/device.h) |
@@ -358,7 +358,7 @@ DRIVER_ATTR(_name, _mode, _show, _store) | |||
358 | 358 | ||
359 | Creation/Removal: | 359 | Creation/Removal: |
360 | 360 | ||
361 | int driver_create_file(struct device_driver *, struct driver_attribute *); | 361 | int driver_create_file(struct device_driver *, const struct driver_attribute *); |
362 | void driver_remove_file(struct device_driver *, struct driver_attribute *); | 362 | void driver_remove_file(struct device_driver *, const struct driver_attribute *); |
363 | 363 | ||
364 | 364 | ||
diff --git a/Documentation/hwmon/k10temp b/Documentation/hwmon/k10temp new file mode 100644 index 000000000000..a7a18d453a51 --- /dev/null +++ b/Documentation/hwmon/k10temp | |||
@@ -0,0 +1,60 @@ | |||
1 | Kernel driver k10temp | ||
2 | ===================== | ||
3 | |||
4 | Supported chips: | ||
5 | * AMD Family 10h processors: | ||
6 | Socket F: Quad-Core/Six-Core/Embedded Opteron | ||
7 | Socket AM2+: Opteron, Phenom (II) X3/X4 | ||
8 | Socket AM3: Quad-Core Opteron, Athlon/Phenom II X2/X3/X4, Sempron II | ||
9 | Socket S1G3: Athlon II, Sempron, Turion II | ||
10 | * AMD Family 11h processors: | ||
11 | Socket S1G2: Athlon (X2), Sempron (X2), Turion X2 (Ultra) | ||
12 | |||
13 | Prefix: 'k10temp' | ||
14 | Addresses scanned: PCI space | ||
15 | Datasheets: | ||
16 | BIOS and Kernel Developer's Guide (BKDG) For AMD Family 10h Processors: | ||
17 | http://support.amd.com/us/Processor_TechDocs/31116.pdf | ||
18 | BIOS and Kernel Developer's Guide (BKDG) for AMD Family 11h Processors: | ||
19 | http://support.amd.com/us/Processor_TechDocs/41256.pdf | ||
20 | Revision Guide for AMD Family 10h Processors: | ||
21 | http://support.amd.com/us/Processor_TechDocs/41322.pdf | ||
22 | Revision Guide for AMD Family 11h Processors: | ||
23 | http://support.amd.com/us/Processor_TechDocs/41788.pdf | ||
24 | AMD Family 11h Processor Power and Thermal Data Sheet for Notebooks: | ||
25 | http://support.amd.com/us/Processor_TechDocs/43373.pdf | ||
26 | AMD Family 10h Server and Workstation Processor Power and Thermal Data Sheet: | ||
27 | http://support.amd.com/us/Processor_TechDocs/43374.pdf | ||
28 | AMD Family 10h Desktop Processor Power and Thermal Data Sheet: | ||
29 | http://support.amd.com/us/Processor_TechDocs/43375.pdf | ||
30 | |||
31 | Author: Clemens Ladisch <clemens@ladisch.de> | ||
32 | |||
33 | Description | ||
34 | ----------- | ||
35 | |||
36 | This driver permits reading of the internal temperature sensor of AMD | ||
37 | Family 10h and 11h processors. | ||
38 | |||
39 | All these processors have a sensor, but on older revisions of Family 10h | ||
40 | processors, the sensor may return inconsistent values (erratum 319). The | ||
41 | driver will refuse to load on these revisions unless you specify the | ||
42 | "force=1" module parameter. | ||
43 | |||
44 | There is one temperature measurement value, available as temp1_input in | ||
45 | sysfs. It is measured in degrees Celsius with a resolution of 1/8th degree. | ||
46 | Please note that it is defined as a relative value; to quote the AMD manual: | ||
47 | |||
48 | Tctl is the processor temperature control value, used by the platform to | ||
49 | control cooling systems. Tctl is a non-physical temperature on an | ||
50 | arbitrary scale measured in degrees. It does _not_ represent an actual | ||
51 | physical temperature like die or case temperature. Instead, it specifies | ||
52 | the processor temperature relative to the point at which the system must | ||
53 | supply the maximum cooling for the processor's specified maximum case | ||
54 | temperature and maximum thermal power dissipation. | ||
55 | |||
56 | The maximum value for Tctl is available in the file temp1_max. | ||
57 | |||
58 | If the BIOS has enabled hardware temperature control, the threshold at | ||
59 | which the processor will throttle itself to avoid damage is available in | ||
60 | temp1_crit and temp1_crit_hyst. | ||
diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt index bb3bf38f03da..6f8c1cabbc5d 100644 --- a/Documentation/kbuild/kbuild.txt +++ b/Documentation/kbuild/kbuild.txt | |||
@@ -1,3 +1,17 @@ | |||
1 | Output files | ||
2 | |||
3 | modules.order | ||
4 | -------------------------------------------------- | ||
5 | This file records the order in which modules appear in Makefiles. This | ||
6 | is used by modprobe to deterministically resolve aliases that match | ||
7 | multiple modules. | ||
8 | |||
9 | modules.builtin | ||
10 | -------------------------------------------------- | ||
11 | This file lists all modules that are built into the kernel. This is used | ||
12 | by modprobe to not fail when trying to load something builtin. | ||
13 | |||
14 | |||
1 | Environment variables | 15 | Environment variables |
2 | 16 | ||
3 | KCPPFLAGS | 17 | KCPPFLAGS |
diff --git a/Documentation/kbuild/kconfig.txt b/Documentation/kbuild/kconfig.txt index 849b5e56d06f..49efae703979 100644 --- a/Documentation/kbuild/kconfig.txt +++ b/Documentation/kbuild/kconfig.txt | |||
@@ -103,10 +103,16 @@ KCONFIG_AUTOCONFIG | |||
103 | This environment variable can be set to specify the path & name of the | 103 | This environment variable can be set to specify the path & name of the |
104 | "auto.conf" file. Its default value is "include/config/auto.conf". | 104 | "auto.conf" file. Its default value is "include/config/auto.conf". |
105 | 105 | ||
106 | KCONFIG_TRISTATE | ||
107 | -------------------------------------------------- | ||
108 | This environment variable can be set to specify the path & name of the | ||
109 | "tristate.conf" file. Its default value is "include/config/tristate.conf". | ||
110 | |||
106 | KCONFIG_AUTOHEADER | 111 | KCONFIG_AUTOHEADER |
107 | -------------------------------------------------- | 112 | -------------------------------------------------- |
108 | This environment variable can be set to specify the path & name of the | 113 | This environment variable can be set to specify the path & name of the |
109 | "autoconf.h" (header) file. Its default value is "include/linux/autoconf.h". | 114 | "autoconf.h" (header) file. |
115 | Its default value is "include/generated/autoconf.h". | ||
110 | 116 | ||
111 | 117 | ||
112 | ====================================================================== | 118 | ====================================================================== |
diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index 4a3109b28847..356fd86f4ea8 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt | |||
@@ -42,80 +42,81 @@ struct dev_pm_ops { | |||
42 | ... | 42 | ... |
43 | }; | 43 | }; |
44 | 44 | ||
45 | The ->runtime_suspend() callback is executed by the PM core for the bus type of | 45 | The ->runtime_suspend(), ->runtime_resume() and ->runtime_idle() callbacks are |
46 | the device being suspended. The bus type's callback is then _entirely_ | 46 | executed by the PM core for either the bus type, or device type (if the bus |
47 | _responsible_ for handling the device as appropriate, which may, but need not | 47 | type's callback is not defined), or device class (if the bus type's and device |
48 | include executing the device driver's own ->runtime_suspend() callback (from the | 48 | type's callbacks are not defined) of given device. The bus type, device type |
49 | and device class callbacks are referred to as subsystem-level callbacks in what | ||
50 | follows. | ||
51 | |||
52 | The subsystem-level suspend callback is _entirely_ _responsible_ for handling | ||
53 | the suspend of the device as appropriate, which may, but need not include | ||
54 | executing the device driver's own ->runtime_suspend() callback (from the | ||
49 | PM core's point of view it is not necessary to implement a ->runtime_suspend() | 55 | PM core's point of view it is not necessary to implement a ->runtime_suspend() |
50 | callback in a device driver as long as the bus type's ->runtime_suspend() knows | 56 | callback in a device driver as long as the subsystem-level suspend callback |
51 | what to do to handle the device). | 57 | knows what to do to handle the device). |
52 | 58 | ||
53 | * Once the bus type's ->runtime_suspend() callback has completed successfully | 59 | * Once the subsystem-level suspend callback has completed successfully |
54 | for given device, the PM core regards the device as suspended, which need | 60 | for given device, the PM core regards the device as suspended, which need |
55 | not mean that the device has been put into a low power state. It is | 61 | not mean that the device has been put into a low power state. It is |
56 | supposed to mean, however, that the device will not process data and will | 62 | supposed to mean, however, that the device will not process data and will |
57 | not communicate with the CPU(s) and RAM until its bus type's | 63 | not communicate with the CPU(s) and RAM until the subsystem-level resume |
58 | ->runtime_resume() callback is executed for it. The run-time PM status of | 64 | callback is executed for it. The run-time PM status of a device after |
59 | a device after successful execution of its bus type's ->runtime_suspend() | 65 | successful execution of the subsystem-level suspend callback is 'suspended'. |
60 | callback is 'suspended'. | 66 | |
61 | 67 | * If the subsystem-level suspend callback returns -EBUSY or -EAGAIN, | |
62 | * If the bus type's ->runtime_suspend() callback returns -EBUSY or -EAGAIN, | 68 | the device's run-time PM status is 'active', which means that the device |
63 | the device's run-time PM status is supposed to be 'active', which means that | 69 | _must_ be fully operational afterwards. |
64 | the device _must_ be fully operational afterwards. | 70 | |
65 | 71 | * If the subsystem-level suspend callback returns an error code different | |
66 | * If the bus type's ->runtime_suspend() callback returns an error code | 72 | from -EBUSY or -EAGAIN, the PM core regards this as a fatal error and will |
67 | different from -EBUSY or -EAGAIN, the PM core regards this as a fatal | 73 | refuse to run the helper functions described in Section 4 for the device, |
68 | error and will refuse to run the helper functions described in Section 4 | 74 | until the status of it is directly set either to 'active', or to 'suspended' |
69 | for the device, until the status of it is directly set either to 'active' | 75 | (the PM core provides special helper functions for this purpose). |
70 | or to 'suspended' (the PM core provides special helper functions for this | 76 | |
71 | purpose). | 77 | In particular, if the driver requires remote wake-up capability (i.e. hardware |
72 | 78 | mechanism allowing the device to request a change of its power state, such as | |
73 | In particular, if the driver requires remote wakeup capability for proper | 79 | PCI PME) for proper functioning and device_run_wake() returns 'false' for the |
74 | functioning and device_run_wake() returns 'false' for the device, then | 80 | device, then ->runtime_suspend() should return -EBUSY. On the other hand, if |
75 | ->runtime_suspend() should return -EBUSY. On the other hand, if | 81 | device_run_wake() returns 'true' for the device and the device is put into a low |
76 | device_run_wake() returns 'true' for the device and the device is put | 82 | power state during the execution of the subsystem-level suspend callback, it is |
77 | into a low power state during the execution of its bus type's | 83 | expected that remote wake-up will be enabled for the device. Generally, remote |
78 | ->runtime_suspend(), it is expected that remote wake-up (i.e. hardware mechanism | 84 | wake-up should be enabled for all input devices put into a low power state at |
79 | allowing the device to request a change of its power state, such as PCI PME) | 85 | run time. |
80 | will be enabled for the device. Generally, remote wake-up should be enabled | 86 | |
81 | for all input devices put into a low power state at run time. | 87 | The subsystem-level resume callback is _entirely_ _responsible_ for handling the |
82 | 88 | resume of the device as appropriate, which may, but need not include executing | |
83 | The ->runtime_resume() callback is executed by the PM core for the bus type of | 89 | the device driver's own ->runtime_resume() callback (from the PM core's point of |
84 | the device being woken up. The bus type's callback is then _entirely_ | 90 | view it is not necessary to implement a ->runtime_resume() callback in a device |
85 | _responsible_ for handling the device as appropriate, which may, but need not | 91 | driver as long as the subsystem-level resume callback knows what to do to handle |
86 | include executing the device driver's own ->runtime_resume() callback (from the | 92 | the device). |
87 | PM core's point of view it is not necessary to implement a ->runtime_resume() | 93 | |
88 | callback in a device driver as long as the bus type's ->runtime_resume() knows | 94 | * Once the subsystem-level resume callback has completed successfully, the PM |
89 | what to do to handle the device). | 95 | core regards the device as fully operational, which means that the device |
90 | 96 | _must_ be able to complete I/O operations as needed. The run-time PM status | |
91 | * Once the bus type's ->runtime_resume() callback has completed successfully, | 97 | of the device is then 'active'. |
92 | the PM core regards the device as fully operational, which means that the | 98 | |
93 | device _must_ be able to complete I/O operations as needed. The run-time | 99 | * If the subsystem-level resume callback returns an error code, the PM core |
94 | PM status of the device is then 'active'. | 100 | regards this as a fatal error and will refuse to run the helper functions |
95 | 101 | described in Section 4 for the device, until its status is directly set | |
96 | * If the bus type's ->runtime_resume() callback returns an error code, the PM | 102 | either to 'active' or to 'suspended' (the PM core provides special helper |
97 | core regards this as a fatal error and will refuse to run the helper | 103 | functions for this purpose). |
98 | functions described in Section 4 for the device, until its status is | 104 | |
99 | directly set either to 'active' or to 'suspended' (the PM core provides | 105 | The subsystem-level idle callback is executed by the PM core whenever the device |
100 | special helper functions for this purpose). | 106 | appears to be idle, which is indicated to the PM core by two counters, the |
101 | 107 | device's usage counter and the counter of 'active' children of the device. | |
102 | The ->runtime_idle() callback is executed by the PM core for the bus type of | ||
103 | given device whenever the device appears to be idle, which is indicated to the | ||
104 | PM core by two counters, the device's usage counter and the counter of 'active' | ||
105 | children of the device. | ||
106 | 108 | ||
107 | * If any of these counters is decreased using a helper function provided by | 109 | * If any of these counters is decreased using a helper function provided by |
108 | the PM core and it turns out to be equal to zero, the other counter is | 110 | the PM core and it turns out to be equal to zero, the other counter is |
109 | checked. If that counter also is equal to zero, the PM core executes the | 111 | checked. If that counter also is equal to zero, the PM core executes the |
110 | device bus type's ->runtime_idle() callback (with the device as an | 112 | subsystem-level idle callback with the device as an argument. |
111 | argument). | ||
112 | 113 | ||
113 | The action performed by a bus type's ->runtime_idle() callback is totally | 114 | The action performed by a subsystem-level idle callback is totally dependent on |
114 | dependent on the bus type in question, but the expected and recommended action | 115 | the subsystem in question, but the expected and recommended action is to check |
115 | is to check if the device can be suspended (i.e. if all of the conditions | 116 | if the device can be suspended (i.e. if all of the conditions necessary for |
116 | necessary for suspending the device are satisfied) and to queue up a suspend | 117 | suspending the device are satisfied) and to queue up a suspend request for the |
117 | request for the device in that case. The value returned by this callback is | 118 | device in that case. The value returned by this callback is ignored by the PM |
118 | ignored by the PM core. | 119 | core. |
119 | 120 | ||
120 | The helper functions provided by the PM core, described in Section 4, guarantee | 121 | The helper functions provided by the PM core, described in Section 4, guarantee |
121 | that the following constraints are met with respect to the bus type's run-time | 122 | that the following constraints are met with respect to the bus type's run-time |
@@ -238,41 +239,41 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: | |||
238 | removing the device from device hierarchy | 239 | removing the device from device hierarchy |
239 | 240 | ||
240 | int pm_runtime_idle(struct device *dev); | 241 | int pm_runtime_idle(struct device *dev); |
241 | - execute ->runtime_idle() for the device's bus type; returns 0 on success | 242 | - execute the subsystem-level idle callback for the device; returns 0 on |
242 | or error code on failure, where -EINPROGRESS means that ->runtime_idle() | 243 | success or error code on failure, where -EINPROGRESS means that |
243 | is already being executed | 244 | ->runtime_idle() is already being executed |
244 | 245 | ||
245 | int pm_runtime_suspend(struct device *dev); | 246 | int pm_runtime_suspend(struct device *dev); |
246 | - execute ->runtime_suspend() for the device's bus type; returns 0 on | 247 | - execute the subsystem-level suspend callback for the device; returns 0 on |
247 | success, 1 if the device's run-time PM status was already 'suspended', or | 248 | success, 1 if the device's run-time PM status was already 'suspended', or |
248 | error code on failure, where -EAGAIN or -EBUSY means it is safe to attempt | 249 | error code on failure, where -EAGAIN or -EBUSY means it is safe to attempt |
249 | to suspend the device again in future | 250 | to suspend the device again in future |
250 | 251 | ||
251 | int pm_runtime_resume(struct device *dev); | 252 | int pm_runtime_resume(struct device *dev); |
252 | - execute ->runtime_resume() for the device's bus type; returns 0 on | 253 | - execute the subsystem-leve resume callback for the device; returns 0 on |
253 | success, 1 if the device's run-time PM status was already 'active' or | 254 | success, 1 if the device's run-time PM status was already 'active' or |
254 | error code on failure, where -EAGAIN means it may be safe to attempt to | 255 | error code on failure, where -EAGAIN means it may be safe to attempt to |
255 | resume the device again in future, but 'power.runtime_error' should be | 256 | resume the device again in future, but 'power.runtime_error' should be |
256 | checked additionally | 257 | checked additionally |
257 | 258 | ||
258 | int pm_request_idle(struct device *dev); | 259 | int pm_request_idle(struct device *dev); |
259 | - submit a request to execute ->runtime_idle() for the device's bus type | 260 | - submit a request to execute the subsystem-level idle callback for the |
260 | (the request is represented by a work item in pm_wq); returns 0 on success | 261 | device (the request is represented by a work item in pm_wq); returns 0 on |
261 | or error code if the request has not been queued up | 262 | success or error code if the request has not been queued up |
262 | 263 | ||
263 | int pm_schedule_suspend(struct device *dev, unsigned int delay); | 264 | int pm_schedule_suspend(struct device *dev, unsigned int delay); |
264 | - schedule the execution of ->runtime_suspend() for the device's bus type | 265 | - schedule the execution of the subsystem-level suspend callback for the |
265 | in future, where 'delay' is the time to wait before queuing up a suspend | 266 | device in future, where 'delay' is the time to wait before queuing up a |
266 | work item in pm_wq, in milliseconds (if 'delay' is zero, the work item is | 267 | suspend work item in pm_wq, in milliseconds (if 'delay' is zero, the work |
267 | queued up immediately); returns 0 on success, 1 if the device's PM | 268 | item is queued up immediately); returns 0 on success, 1 if the device's PM |
268 | run-time status was already 'suspended', or error code if the request | 269 | run-time status was already 'suspended', or error code if the request |
269 | hasn't been scheduled (or queued up if 'delay' is 0); if the execution of | 270 | hasn't been scheduled (or queued up if 'delay' is 0); if the execution of |
270 | ->runtime_suspend() is already scheduled and not yet expired, the new | 271 | ->runtime_suspend() is already scheduled and not yet expired, the new |
271 | value of 'delay' will be used as the time to wait | 272 | value of 'delay' will be used as the time to wait |
272 | 273 | ||
273 | int pm_request_resume(struct device *dev); | 274 | int pm_request_resume(struct device *dev); |
274 | - submit a request to execute ->runtime_resume() for the device's bus type | 275 | - submit a request to execute the subsystem-level resume callback for the |
275 | (the request is represented by a work item in pm_wq); returns 0 on | 276 | device (the request is represented by a work item in pm_wq); returns 0 on |
276 | success, 1 if the device's run-time PM status was already 'active', or | 277 | success, 1 if the device's run-time PM status was already 'active', or |
277 | error code if the request hasn't been queued up | 278 | error code if the request hasn't been queued up |
278 | 279 | ||
@@ -303,12 +304,12 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: | |||
303 | run-time PM callbacks described in Section 2 | 304 | run-time PM callbacks described in Section 2 |
304 | 305 | ||
305 | int pm_runtime_disable(struct device *dev); | 306 | int pm_runtime_disable(struct device *dev); |
306 | - prevent the run-time PM helper functions from running the device bus | 307 | - prevent the run-time PM helper functions from running subsystem-level |
307 | type's run-time PM callbacks, make sure that all of the pending run-time | 308 | run-time PM callbacks for the device, make sure that all of the pending |
308 | PM operations on the device are either completed or canceled; returns | 309 | run-time PM operations on the device are either completed or canceled; |
309 | 1 if there was a resume request pending and it was necessary to execute | 310 | returns 1 if there was a resume request pending and it was necessary to |
310 | ->runtime_resume() for the device's bus type to satisfy that request, | 311 | execute the subsystem-level resume callback for the device to satisfy that |
311 | otherwise 0 is returned | 312 | request, otherwise 0 is returned |
312 | 313 | ||
313 | void pm_suspend_ignore_children(struct device *dev, bool enable); | 314 | void pm_suspend_ignore_children(struct device *dev, bool enable); |
314 | - set/unset the power.ignore_children flag of the device | 315 | - set/unset the power.ignore_children flag of the device |
@@ -378,5 +379,55 @@ pm_runtime_suspend() or pm_runtime_idle() or their asynchronous counterparts, | |||
378 | they will fail returning -EAGAIN, because the device's usage counter is | 379 | they will fail returning -EAGAIN, because the device's usage counter is |
379 | incremented by the core before executing ->probe() and ->remove(). Still, it | 380 | incremented by the core before executing ->probe() and ->remove(). Still, it |
380 | may be desirable to suspend the device as soon as ->probe() or ->remove() has | 381 | may be desirable to suspend the device as soon as ->probe() or ->remove() has |
381 | finished, so the PM core uses pm_runtime_idle_sync() to invoke the device bus | 382 | finished, so the PM core uses pm_runtime_idle_sync() to invoke the |
382 | type's ->runtime_idle() callback at that time. | 383 | subsystem-level idle callback for the device at that time. |
384 | |||
385 | 6. Run-time PM and System Sleep | ||
386 | |||
387 | Run-time PM and system sleep (i.e., system suspend and hibernation, also known | ||
388 | as suspend-to-RAM and suspend-to-disk) interact with each other in a couple of | ||
389 | ways. If a device is active when a system sleep starts, everything is | ||
390 | straightforward. But what should happen if the device is already suspended? | ||
391 | |||
392 | The device may have different wake-up settings for run-time PM and system sleep. | ||
393 | For example, remote wake-up may be enabled for run-time suspend but disallowed | ||
394 | for system sleep (device_may_wakeup(dev) returns 'false'). When this happens, | ||
395 | the subsystem-level system suspend callback is responsible for changing the | ||
396 | device's wake-up setting (it may leave that to the device driver's system | ||
397 | suspend routine). It may be necessary to resume the device and suspend it again | ||
398 | in order to do so. The same is true if the driver uses different power levels | ||
399 | or other settings for run-time suspend and system sleep. | ||
400 | |||
401 | During system resume, devices generally should be brought back to full power, | ||
402 | even if they were suspended before the system sleep began. There are several | ||
403 | reasons for this, including: | ||
404 | |||
405 | * The device might need to switch power levels, wake-up settings, etc. | ||
406 | |||
407 | * Remote wake-up events might have been lost by the firmware. | ||
408 | |||
409 | * The device's children may need the device to be at full power in order | ||
410 | to resume themselves. | ||
411 | |||
412 | * The driver's idea of the device state may not agree with the device's | ||
413 | physical state. This can happen during resume from hibernation. | ||
414 | |||
415 | * The device might need to be reset. | ||
416 | |||
417 | * Even though the device was suspended, if its usage counter was > 0 then most | ||
418 | likely it would need a run-time resume in the near future anyway. | ||
419 | |||
420 | * Always going back to full power is simplest. | ||
421 | |||
422 | If the device was suspended before the sleep began, then its run-time PM status | ||
423 | will have to be updated to reflect the actual post-system sleep status. The way | ||
424 | to do this is: | ||
425 | |||
426 | pm_runtime_disable(dev); | ||
427 | pm_runtime_set_active(dev); | ||
428 | pm_runtime_enable(dev); | ||
429 | |||
430 | The PM core always increments the run-time usage counter before calling the | ||
431 | ->prepare() callback and decrements it after calling the ->complete() callback. | ||
432 | Hence disabling run-time PM temporarily like this will not cause any run-time | ||
433 | suspend callbacks to be lost. | ||
diff --git a/Documentation/powerpc/dts-bindings/fsl/mpic.txt b/Documentation/powerpc/dts-bindings/fsl/mpic.txt new file mode 100644 index 000000000000..71e39cf3215b --- /dev/null +++ b/Documentation/powerpc/dts-bindings/fsl/mpic.txt | |||
@@ -0,0 +1,42 @@ | |||
1 | * OpenPIC and its interrupt numbers on Freescale's e500/e600 cores | ||
2 | |||
3 | The OpenPIC specification does not specify which interrupt source has to | ||
4 | become which interrupt number. This is up to the software implementation | ||
5 | of the interrupt controller. The only requirement is that every | ||
6 | interrupt source has to have an unique interrupt number / vector number. | ||
7 | To accomplish this the current implementation assigns the number zero to | ||
8 | the first source, the number one to the second source and so on until | ||
9 | all interrupt sources have their unique number. | ||
10 | Usually the assigned vector number equals the interrupt number mentioned | ||
11 | in the documentation for a given core / CPU. This is however not true | ||
12 | for the e500 cores (MPC85XX CPUs) where the documentation distinguishes | ||
13 | between internal and external interrupt sources and starts counting at | ||
14 | zero for both of them. | ||
15 | |||
16 | So what to write for external interrupt source X or internal interrupt | ||
17 | source Y into the device tree? Here is an example: | ||
18 | |||
19 | The memory map for the interrupt controller in the MPC8544[0] shows, | ||
20 | that the first interrupt source starts at 0x5_0000 (PIC Register Address | ||
21 | Map-Interrupt Source Configuration Registers). This source becomes the | ||
22 | number zero therefore: | ||
23 | External interrupt 0 = interrupt number 0 | ||
24 | External interrupt 1 = interrupt number 1 | ||
25 | External interrupt 2 = interrupt number 2 | ||
26 | ... | ||
27 | Every interrupt number allocates 0x20 bytes register space. So to get | ||
28 | its number it is sufficient to shift the lower 16bits to right by five. | ||
29 | So for the external interrupt 10 we have: | ||
30 | 0x0140 >> 5 = 10 | ||
31 | |||
32 | After the external sources, the internal sources follow. The in core I2C | ||
33 | controller on the MPC8544 for instance has the internal source number | ||
34 | 27. Oo obtain its interrupt number we take the lower 16bits of its memory | ||
35 | address (0x5_0560) and shift it right: | ||
36 | 0x0560 >> 5 = 43 | ||
37 | |||
38 | Therefore the I2C device node for the MPC8544 CPU has to have the | ||
39 | interrupt number 43 specified in the device tree. | ||
40 | |||
41 | [0] MPC8544E PowerQUICCTM III, Integrated Host Processor Family Reference Manual | ||
42 | MPC8544ERM Rev. 1 10/2007 | ||
diff --git a/Documentation/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt index e93affff3af8..e72cee9e2a71 100644 --- a/Documentation/sound/alsa/HD-Audio-Models.txt +++ b/Documentation/sound/alsa/HD-Audio-Models.txt | |||
@@ -403,4 +403,5 @@ STAC9872 | |||
403 | Cirrus Logic CS4206/4207 | 403 | Cirrus Logic CS4206/4207 |
404 | ======================== | 404 | ======================== |
405 | mbp55 MacBook Pro 5,5 | 405 | mbp55 MacBook Pro 5,5 |
406 | imac27 IMac 27 Inch | ||
406 | auto BIOS setup (default) | 407 | auto BIOS setup (default) |
diff --git a/Documentation/stable_kernel_rules.txt b/Documentation/stable_kernel_rules.txt index a452227361b1..5effa5bd993b 100644 --- a/Documentation/stable_kernel_rules.txt +++ b/Documentation/stable_kernel_rules.txt | |||
@@ -26,13 +26,33 @@ Procedure for submitting patches to the -stable tree: | |||
26 | 26 | ||
27 | - Send the patch, after verifying that it follows the above rules, to | 27 | - Send the patch, after verifying that it follows the above rules, to |
28 | stable@kernel.org. | 28 | stable@kernel.org. |
29 | - To have the patch automatically included in the stable tree, add the | ||
30 | the tag | ||
31 | Cc: stable@kernel.org | ||
32 | in the sign-off area. Once the patch is merged it will be applied to | ||
33 | the stable tree without anything else needing to be done by the author | ||
34 | or subsystem maintainer. | ||
35 | - If the patch requires other patches as prerequisites which can be | ||
36 | cherry-picked than this can be specified in the following format in | ||
37 | the sign-off area: | ||
38 | |||
39 | Cc: <stable@kernel.org> # .32.x: a1f84a3: sched: Check for idle | ||
40 | Cc: <stable@kernel.org> # .32.x: 1b9508f: sched: Rate-limit newidle | ||
41 | Cc: <stable@kernel.org> # .32.x: fd21073: sched: Fix affinity logic | ||
42 | Cc: <stable@kernel.org> # .32.x | ||
43 | Signed-off-by: Ingo Molnar <mingo@elte.hu> | ||
44 | |||
45 | The tag sequence has the meaning of: | ||
46 | git cherry-pick a1f84a3 | ||
47 | git cherry-pick 1b9508f | ||
48 | git cherry-pick fd21073 | ||
49 | git cherry-pick <this commit> | ||
50 | |||
29 | - The sender will receive an ACK when the patch has been accepted into the | 51 | - The sender will receive an ACK when the patch has been accepted into the |
30 | queue, or a NAK if the patch is rejected. This response might take a few | 52 | queue, or a NAK if the patch is rejected. This response might take a few |
31 | days, according to the developer's schedules. | 53 | days, according to the developer's schedules. |
32 | - If accepted, the patch will be added to the -stable queue, for review by | 54 | - If accepted, the patch will be added to the -stable queue, for review by |
33 | other developers and by the relevant subsystem maintainer. | 55 | other developers and by the relevant subsystem maintainer. |
34 | - If the stable@kernel.org address is added to a patch, when it goes into | ||
35 | Linus's tree it will automatically be emailed to the stable team. | ||
36 | - Security patches should not be sent to this alias, but instead to the | 56 | - Security patches should not be sent to this alias, but instead to the |
37 | documented security@kernel.org address. | 57 | documented security@kernel.org address. |
38 | 58 | ||
diff --git a/Documentation/trace/events-kmem.txt b/Documentation/trace/events-kmem.txt index 6ef2a8652e17..aa82ee4a5a87 100644 --- a/Documentation/trace/events-kmem.txt +++ b/Documentation/trace/events-kmem.txt | |||
@@ -1,7 +1,7 @@ | |||
1 | Subsystem Trace Points: kmem | 1 | Subsystem Trace Points: kmem |
2 | 2 | ||
3 | The tracing system kmem captures events related to object and page allocation | 3 | The kmem tracing system captures events related to object and page allocation |
4 | within the kernel. Broadly speaking there are four major subheadings. | 4 | within the kernel. Broadly speaking there are five major subheadings. |
5 | 5 | ||
6 | o Slab allocation of small objects of unknown type (kmalloc) | 6 | o Slab allocation of small objects of unknown type (kmalloc) |
7 | o Slab allocation of small objects of known type | 7 | o Slab allocation of small objects of known type |
@@ -9,7 +9,7 @@ within the kernel. Broadly speaking there are four major subheadings. | |||
9 | o Per-CPU Allocator Activity | 9 | o Per-CPU Allocator Activity |
10 | o External Fragmentation | 10 | o External Fragmentation |
11 | 11 | ||
12 | This document will describe what each of the tracepoints are and why they | 12 | This document describes what each of the tracepoints is and why they |
13 | might be useful. | 13 | might be useful. |
14 | 14 | ||
15 | 1. Slab allocation of small objects of unknown type | 15 | 1. Slab allocation of small objects of unknown type |
@@ -34,7 +34,7 @@ kmem_cache_free call_site=%lx ptr=%p | |||
34 | These events are similar in usage to the kmalloc-related events except that | 34 | These events are similar in usage to the kmalloc-related events except that |
35 | it is likely easier to pin the event down to a specific cache. At the time | 35 | it is likely easier to pin the event down to a specific cache. At the time |
36 | of writing, no information is available on what slab is being allocated from, | 36 | of writing, no information is available on what slab is being allocated from, |
37 | but the call_site can usually be used to extrapolate that information | 37 | but the call_site can usually be used to extrapolate that information. |
38 | 38 | ||
39 | 3. Page allocation | 39 | 3. Page allocation |
40 | ================== | 40 | ================== |
@@ -80,9 +80,9 @@ event indicating whether it is for a percpu_refill or not. | |||
80 | When the per-CPU list is too full, a number of pages are freed, each one | 80 | When the per-CPU list is too full, a number of pages are freed, each one |
81 | which triggers a mm_page_pcpu_drain event. | 81 | which triggers a mm_page_pcpu_drain event. |
82 | 82 | ||
83 | The individual nature of the events are so that pages can be tracked | 83 | The individual nature of the events is so that pages can be tracked |
84 | between allocation and freeing. A number of drain or refill pages that occur | 84 | between allocation and freeing. A number of drain or refill pages that occur |
85 | consecutively imply the zone->lock being taken once. Large amounts of PCP | 85 | consecutively imply the zone->lock being taken once. Large amounts of per-CPU |
86 | refills and drains could imply an imbalance between CPUs where too much work | 86 | refills and drains could imply an imbalance between CPUs where too much work |
87 | is being concentrated in one place. It could also indicate that the per-CPU | 87 | is being concentrated in one place. It could also indicate that the per-CPU |
88 | lists should be a larger size. Finally, large amounts of refills on one CPU | 88 | lists should be a larger size. Finally, large amounts of refills on one CPU |
@@ -102,6 +102,6 @@ is important. | |||
102 | 102 | ||
103 | Large numbers of this event implies that memory is fragmenting and | 103 | Large numbers of this event implies that memory is fragmenting and |
104 | high-order allocations will start failing at some time in the future. One | 104 | high-order allocations will start failing at some time in the future. One |
105 | means of reducing the occurange of this event is to increase the size of | 105 | means of reducing the occurrence of this event is to increase the size of |
106 | min_free_kbytes in increments of 3*pageblock_size*nr_online_nodes where | 106 | min_free_kbytes in increments of 3*pageblock_size*nr_online_nodes where |
107 | pageblock_size is usually the size of the default hugepage size. | 107 | pageblock_size is usually the size of the default hugepage size. |
diff --git a/Documentation/usb/power-management.txt b/Documentation/usb/power-management.txt index c7c1dc2f8017..3bf6818c8cf5 100644 --- a/Documentation/usb/power-management.txt +++ b/Documentation/usb/power-management.txt | |||
@@ -71,12 +71,10 @@ being accessed through sysfs, then it definitely is idle. | |||
71 | Forms of dynamic PM | 71 | Forms of dynamic PM |
72 | ------------------- | 72 | ------------------- |
73 | 73 | ||
74 | Dynamic suspends can occur in two ways: manual and automatic. | 74 | Dynamic suspends occur when the kernel decides to suspend an idle |
75 | "Manual" means that the user has told the kernel to suspend a device, | 75 | device. This is called "autosuspend" for short. In general, a device |
76 | whereas "automatic" means that the kernel has decided all by itself to | 76 | won't be autosuspended unless it has been idle for some minimum period |
77 | suspend a device. Automatic suspend is called "autosuspend" for | 77 | of time, the so-called idle-delay time. |
78 | short. In general, a device won't be autosuspended unless it has been | ||
79 | idle for some minimum period of time, the so-called idle-delay time. | ||
80 | 78 | ||
81 | Of course, nothing the kernel does on its own initiative should | 79 | Of course, nothing the kernel does on its own initiative should |
82 | prevent the computer or its devices from working properly. If a | 80 | prevent the computer or its devices from working properly. If a |
@@ -96,10 +94,11 @@ idle. | |||
96 | We can categorize power management events in two broad classes: | 94 | We can categorize power management events in two broad classes: |
97 | external and internal. External events are those triggered by some | 95 | external and internal. External events are those triggered by some |
98 | agent outside the USB stack: system suspend/resume (triggered by | 96 | agent outside the USB stack: system suspend/resume (triggered by |
99 | userspace), manual dynamic suspend/resume (also triggered by | 97 | userspace), manual dynamic resume (also triggered by userspace), and |
100 | userspace), and remote wakeup (triggered by the device). Internal | 98 | remote wakeup (triggered by the device). Internal events are those |
101 | events are those triggered within the USB stack: autosuspend and | 99 | triggered within the USB stack: autosuspend and autoresume. Note that |
102 | autoresume. | 100 | all dynamic suspend events are internal; external agents are not |
101 | allowed to issue dynamic suspends. | ||
103 | 102 | ||
104 | 103 | ||
105 | The user interface for dynamic PM | 104 | The user interface for dynamic PM |
@@ -145,9 +144,9 @@ relevant attribute files are: wakeup, level, and autosuspend. | |||
145 | number of seconds the device should remain idle before | 144 | number of seconds the device should remain idle before |
146 | the kernel will autosuspend it (the idle-delay time). | 145 | the kernel will autosuspend it (the idle-delay time). |
147 | The default is 2. 0 means to autosuspend as soon as | 146 | The default is 2. 0 means to autosuspend as soon as |
148 | the device becomes idle, and -1 means never to | 147 | the device becomes idle, and negative values mean |
149 | autosuspend. You can write a number to the file to | 148 | never to autosuspend. You can write a number to the |
150 | change the autosuspend idle-delay time. | 149 | file to change the autosuspend idle-delay time. |
151 | 150 | ||
152 | Writing "-1" to power/autosuspend and writing "on" to power/level do | 151 | Writing "-1" to power/autosuspend and writing "on" to power/level do |
153 | essentially the same thing -- they both prevent the device from being | 152 | essentially the same thing -- they both prevent the device from being |
@@ -377,9 +376,9 @@ the device hasn't been idle for long enough, a delayed workqueue | |||
377 | routine is automatically set up to carry out the operation when the | 376 | routine is automatically set up to carry out the operation when the |
378 | autosuspend idle-delay has expired. | 377 | autosuspend idle-delay has expired. |
379 | 378 | ||
380 | Autoresume attempts also can fail. This will happen if power/level is | 379 | Autoresume attempts also can fail, although failure would mean that |
381 | set to "suspend" or if the device doesn't manage to resume properly. | 380 | the device is no longer present or operating properly. Unlike |
382 | Unlike autosuspend, there's no delay for an autoresume. | 381 | autosuspend, there's no delay for an autoresume. |
383 | 382 | ||
384 | 383 | ||
385 | Other parts of the driver interface | 384 | Other parts of the driver interface |
@@ -527,13 +526,3 @@ succeed, it may still remain active and thus cause the system to | |||
527 | resume as soon as the system suspend is complete. Or the remote | 526 | resume as soon as the system suspend is complete. Or the remote |
528 | wakeup may fail and get lost. Which outcome occurs depends on timing | 527 | wakeup may fail and get lost. Which outcome occurs depends on timing |
529 | and on the hardware and firmware design. | 528 | and on the hardware and firmware design. |
530 | |||
531 | More interestingly, a device might undergo a manual resume or | ||
532 | autoresume during system suspend. With current kernels this shouldn't | ||
533 | happen, because manual resumes must be initiated by userspace and | ||
534 | autoresumes happen in response to I/O requests, but all user processes | ||
535 | and I/O should be quiescent during a system suspend -- thanks to the | ||
536 | freezer. However there are plans to do away with the freezer, which | ||
537 | would mean these things would become possible. If and when this comes | ||
538 | about, the USB core will carefully arrange matters so that either type | ||
539 | of resume will block until the entire system has resumed. | ||