linux-toradex.git/drivers/base/power/domain.c, branch v4.20-rc6

PM / Domains: Deal with multiple states but no governor in genpd

2018-10-18T10:25:09+00:00

A caller of pm_genpd_init() that provides some states for the genpd via the
->states pointer in the struct generic_pm_domain, should also provide a
governor. This because it's the job of the governor to pick a state that
satisfies the constraints.

Therefore, let's print a warning to inform the user about such bogus
configuration and avoid to bail out, by instead picking the shallowest
state before genpd invokes the ->power_off() callback.

Signed-off-by: Ulf Hansson 
Reviewed-by: Lina Iyer 
Signed-off-by: Rafael J. Wysocki

PM / Domains: Don't treat zero found compatible idle states as an error

2018-10-18T10:25:09+00:00

Instead of returning -EINVAL from of_genpd_parse_idle_states() in case none
compatible states was found, let's return 0 to indicate success. Assign
also the out-parameter *states to NULL and *n to 0, to indicate to the
caller that zero states have been found/allocated.

This enables the caller of of_genpd_parse_idle_states() to easier act on
the returned error code.

Signed-off-by: Ulf Hansson 
Reviewed-by: Lina Iyer 
Signed-off-by: Rafael J. Wysocki

Merge tag 'driver-core-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2018-08-18T18:44:53+00:00

Pull driver core updates from Greg KH:
 "Here are all of the driver core and related patches for 4.19-rc1.

  Nothing huge here, just a number of small cleanups and the ability to
  now stop the deferred probing after init happens.

  All of these have been in linux-next for a while with only a merge
  issue reported"

* tag 'driver-core-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (21 commits)
  base: core: Remove WARN_ON from link dependencies check
  drivers/base: stop new probing during shutdown
  drivers: core: Remove glue dirs from sysfs earlier
  driver core: remove unnecessary function extern declare
  sysfs.h: fix non-kernel-doc comment
  PM / Domains: Stop deferring probe at the end of initcall
  iommu: Remove IOMMU_OF_DECLARE
  iommu: Stop deferring probe at end of initcalls
  pinctrl: Support stopping deferred probe after initcalls
  dt-bindings: pinctrl: add a 'pinctrl-use-default' property
  driver core: allow stopping deferred probe after init
  driver core: add a debugfs entry to show deferred devices
  sysfs: Fix internal_create_group() for named group updates
  base: fix order of OF initialization
  linux/device.h: fix kernel-doc notation warning
  Documentation: update firmware loader fallback reference
  kobject: Replace strncpy with memcpy
  drivers: base: cacheinfo: use OF property_read_u32 instead of get_property,read_number
  kernfs: Replace strncpy with memcpy
  device: Add #define dev_fmt similar to #define pr_fmt
  ...

Merge 4.18-rc7 into driver-core-next

2018-07-30T08:08:09+00:00

We need the driver core changes in here as well for testing.

Signed-off-by: Greg Kroah-Hartman

PM / Domains: Stop deferring probe at the end of initcall

2018-07-10T15:22:35+00:00

All PM domain drivers must be built-in (at least those using DT), so
there is no point deferring probe after initcalls are done. Continuing
to defer probe may prevent booting successfully even if managing PM
domains is not required. This can happen if the user failed to enable
the driver or if power-domains are added to a platform's DT, but there
is not yet a driver (e.g. a new DTB with an old kernel).

Call the driver core function driver_deferred_probe_check_init_done()
instead of just returning -EPROBE_DEFER to stop deferring probe when
initcalls are done.

Acked-by: "Rafael J. Wysocki" 
Cc: Kevin Hilman 
Cc: Ulf Hansson 
Cc: Pavel Machek 
Cc: Len Brown 
Cc: Greg Kroah-Hartman 
Cc: linux-pm@vger.kernel.org
Signed-off-by: Rob Herring 
Signed-off-by: Greg Kroah-Hartman

PM / Domains: Introduce option to attach a device by name to genpd

2018-07-09T10:11:02+00:00

For the multiple PM domain case, let's introduce a new function called
genpd_dev_pm_attach_by_name(). This allows a device to be associated with
its PM domain through genpd, by using a name based lookup.

Note that, genpd_dev_pm_attach_by_name() shall only be called by the driver
core / PM core, similar to how the existing dev_pm_domain_attach_by_id()
makes use of genpd_dev_pm_attach_by_id(). However, this is implemented by
following changes on top.

Signed-off-by: Ulf Hansson 
Tested-by: Rajendra Nayak 
Reviewed-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki

PM / Domains: Don't power on at attach for the multi PM domain case

2018-07-03T14:42:51+00:00

There are no legacy behavior in drivers to consider while attaching a
device to genpd - for the multiple PM domain case.

For that reason, let's instead require the driver to runtime resume the
device, via calling pm_runtime_get_sync() for example, when it needs to
power on the corresponding PM domain.

This allows us to improve the situation during attach. Instead of always
power on the PM domain, which may be unnecessary, let's leave it in its
current state. Additionally, to avoid the PM domain to stay powered on,
let's schedule a power off work.

Fixes: 3c095f32a92b (PM / Domains: Add support for multi PM domains ...)
Signed-off-by: Ulf Hansson 
Acked-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki

PM / Domains: Rename opp_node to np

2018-06-25T07:41:37+00:00

The DT node passed here isn't necessarily an OPP node, as this routine
can also be used for cases where the "required-opps" property is present
directly in the device's node. Rename it.

This also removes a stale comment.

Acked-by: Ulf Hansson 
Signed-off-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki

PM / Domains: Add support for multi PM domains per device to genpd

2018-06-06T07:09:21+00:00

To support devices being partitioned across multiple PM domains, let's
begin with extending genpd to cope with these kind of configurations.

Therefore, add a new exported function genpd_dev_pm_attach_by_id(), which
is similar to the existing genpd_dev_pm_attach(), but with the difference
that it allows its callers to provide an index to the PM domain that it
wants to attach.

Note that, genpd_dev_pm_attach_by_id() shall only be called by the driver
core / PM core, similar to how the existing dev_pm_domain_attach() makes
use of genpd_dev_pm_attach(). However, this is implemented by following
changes on top.

Because, only one PM domain can be attached per device, genpd needs to
create a virtual device that it can attach/detach instead. More precisely,
let the new function genpd_dev_pm_attach_by_id() register a virtual struct
device via calling device_register(). Then let it attach this device to the
corresponding PM domain, rather than the one that is provided by the
caller. The actual attaching is done via re-using the existing genpd OF
functions.

At successful attachment, genpd_dev_pm_attach_by_id() returns the created
virtual device, which allows the caller to operate on it to deal with power
management. Following changes on top, provides more details in this
regards.

To deal with detaching of a PM domain for the multiple PM domains case,
let's also extend the existing genpd_dev_pm_detach() function, to cover the
cleanup of the created virtual device, via make it call device_unregister()
on it. In this way, there is no need to introduce a new function to deal
with detach for the multiple PM domain case, but instead the existing one
is re-used.

Signed-off-by: Ulf Hansson 
Acked-by: Jon Hunter 
Tested-by: Jon Hunter 
Reviewed-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki

PM / Domains: Split genpd_dev_pm_attach()

2018-06-06T07:09:21+00:00

To extend genpd to deal with allowing multiple PM domains per device, some
of the code in genpd_dev_pm_attach() can be re-used. Let's prepare for this
by moving some of the code into a sub-function.

Signed-off-by: Ulf Hansson 
Acked-by: Jon Hunter 
Tested-by: Jon Hunter 
Reviewed-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki