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Commit 8eb2c0ee authored by Keith Packard's avatar Keith Packard
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Merge branch 'drm-intel-fixes' into drm-intel-next

parents 3e0dc6b0 0d72c6fc
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+14 −53
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@@ -520,59 +520,20 @@ Support for power domains is provided through the pwr_domain field of struct
device.  This field is a pointer to an object of type struct dev_power_domain,
defined in include/linux/pm.h, providing a set of power management callbacks
analogous to the subsystem-level and device driver callbacks that are executed
for the given device during all power transitions, in addition to the respective
subsystem-level callbacks.  Specifically, the power domain "suspend" callbacks
(i.e. ->runtime_suspend(), ->suspend(), ->freeze(), ->poweroff(), etc.) are
executed after the analogous subsystem-level callbacks, while the power domain
"resume" callbacks (i.e. ->runtime_resume(), ->resume(), ->thaw(), ->restore,
etc.) are executed before the analogous subsystem-level callbacks.  Error codes
returned by the "suspend" and "resume" power domain callbacks are ignored.

Power domain ->runtime_idle() callback is executed before the subsystem-level
->runtime_idle() callback and the result returned by it is not ignored.  Namely,
if it returns error code, the subsystem-level ->runtime_idle() callback will not
be called and the helper function rpm_idle() executing it will return error
code.  This mechanism is intended to help platforms where saving device state
is a time consuming operation and should only be carried out if all devices
in the power domain are idle, before turning off the shared power resource(s).
Namely, the power domain ->runtime_idle() callback may return error code until
the pm_runtime_idle() helper (or its asychronous version) has been called for
all devices in the power domain (it is recommended that the returned error code
be -EBUSY in those cases), preventing the subsystem-level ->runtime_idle()
callback from being run prematurely.

The support for device power domains is only relevant to platforms needing to
use the same subsystem-level (e.g. platform bus type) and device driver power
management callbacks in many different power domain configurations and wanting
to avoid incorporating the support for power domains into the subsystem-level
callbacks.  The other platforms need not implement it or take it into account
in any way.


System Devices
--------------
System devices (sysdevs) follow a slightly different API, which can be found in

	include/linux/sysdev.h
	drivers/base/sys.c

System devices will be suspended with interrupts disabled, and after all other
devices have been suspended.  On resume, they will be resumed before any other
devices, and also with interrupts disabled.  These things occur in special
"sysdev_driver" phases, which affect only system devices.

Thus, after the suspend_noirq (or freeze_noirq or poweroff_noirq) phase, when
the non-boot CPUs are all offline and IRQs are disabled on the remaining online
CPU, then a sysdev_driver.suspend phase is carried out, and the system enters a
sleep state (or a system image is created).  During resume (or after the image
has been created or loaded) a sysdev_driver.resume phase is carried out, IRQs
are enabled on the only online CPU, the non-boot CPUs are enabled, and the
resume_noirq (or thaw_noirq or restore_noirq) phase begins.

Code to actually enter and exit the system-wide low power state sometimes
involves hardware details that are only known to the boot firmware, and
may leave a CPU running software (from SRAM or flash memory) that monitors
the system and manages its wakeup sequence.
for the given device during all power transitions, instead of the respective
subsystem-level callbacks.  Specifically, if a device's pm_domain pointer is
not NULL, the ->suspend() callback from the object pointed to by it will be
executed instead of its subsystem's (e.g. bus type's) ->suspend() callback and
anlogously for all of the remaining callbacks.  In other words, power management
domain callbacks, if defined for the given device, always take precedence over
the callbacks provided by the device's subsystem (e.g. bus type).

The support for device power management domains is only relevant to platforms
needing to use the same device driver power management callbacks in many
different power domain configurations and wanting to avoid incorporating the
support for power domains into subsystem-level callbacks, for example by
modifying the platform bus type.  Other platforms need not implement it or take
it into account in any way.


Device Low Power (suspend) States
+0 −5
Original line number Diff line number Diff line
@@ -566,11 +566,6 @@ to do this is:
	pm_runtime_set_active(dev);
	pm_runtime_enable(dev);

The PM core always increments the run-time usage counter before calling the
->prepare() callback and decrements it after calling the ->complete() callback.
Hence disabling run-time PM temporarily like this will not cause any run-time
suspend callbacks to be lost.

7. Generic subsystem callbacks

Subsystems may wish to conserve code space by using the set of generic power
+8 −1
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@@ -76,6 +76,13 @@ A transfer's actual_length may be positive even when an error has been
reported.  That's because transfers often involve several packets, so that
one or more packets could finish before an error stops further endpoint I/O.

For isochronous URBs, the urb status value is non-zero only if the URB is
unlinked, the device is removed, the host controller is disabled, or the total
transferred length is less than the requested length and the URB_SHORT_NOT_OK
flag is set.  Completion handlers for isochronous URBs should only see
urb->status set to zero, -ENOENT, -ECONNRESET, -ESHUTDOWN, or -EREMOTEIO.
Individual frame descriptor status fields may report more status codes.


0			Transfer completed successfully

@@ -132,7 +139,7 @@ one or more packets could finish before an error stops further endpoint I/O.
			device removal events immediately.

-EXDEV			ISO transfer only partially completed
			look at individual frame status for details
			(only set in iso_frame_desc[n].status, not urb->status)

-EINVAL			ISO madness, if this happens: Log off and go home

+10 −2
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@@ -6434,8 +6434,9 @@ S: Maintained
F:	drivers/usb/misc/rio500*

USB EHCI DRIVER
M:	Alan Stern <stern@rowland.harvard.edu>
L:	linux-usb@vger.kernel.org
S:	Orphan
S:	Maintained
F:	Documentation/usb/ehci.txt
F:	drivers/usb/host/ehci*

@@ -6465,6 +6466,12 @@ S: Maintained
F:	Documentation/hid/hiddev.txt
F:	drivers/hid/usbhid/

USB/IP DRIVERS
M:	Matt Mooney <mfm@muteddisk.com>
L:	linux-usb@vger.kernel.org
S:	Maintained
F:	drivers/staging/usbip/

USB ISP116X DRIVER
M:	Olav Kongas <ok@artecdesign.ee>
L:	linux-usb@vger.kernel.org
@@ -6494,8 +6501,9 @@ S: Maintained
F:	sound/usb/midi.*

USB OHCI DRIVER
M:	Alan Stern <stern@rowland.harvard.edu>
L:	linux-usb@vger.kernel.org
S:	Orphan
S:	Maintained
F:	Documentation/usb/ohci.txt
F:	drivers/usb/host/ohci*

+1 −1
Original line number Diff line number Diff line
VERSION = 3
PATCHLEVEL = 0
SUBLEVEL = 0
EXTRAVERSION = -rc4
EXTRAVERSION = -rc5
NAME = Sneaky Weasel

# *DOCUMENTATION*
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