linux-stable.git/drivers/base/power/clock_ops.c, branch linux-3.19.y

PM: Drop CONFIG_PM_RUNTIME from the driver core

2014-12-03T23:46:58+00:00

After commit b2b49ccbdd54 (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is
selected) PM_RUNTIME is always set if PM is set, so quite a few
depend on CONFIG_PM or even may be dropped entirely in some cases.

Replace CONFIG_PM_RUNTIME with CONFIG_PM in the PM core code.

Reviewed-by: Ulf Hansson 
Acked-by: Kevin Hilman 
Signed-off-by: Rafael J. Wysocki

PM / clock_ops: make __pm_clk_enable more generic

2014-11-07T00:47:48+00:00

Now there are two places in code which do the same things,
so allow __pm_clk_enable() to accept pointer on pm_clock_entry
structure as second parameter instead of pointer on clock and
remove duplicated code.

Also, updated function intended to be used by following patch.

Signed-off-by: Grygorii Strashko 
Reviewed-by: Dmitry Torokhov 
Signed-off-by: Rafael J. Wysocki

PM / clock_ops: Add pm_clk_add_clk()

2014-11-07T00:46:51+00:00

The existing pm_clk_add() allows to pass a clock by con_id. However,
when referring to a specific clock from DT, no con_id is available.

Add pm_clk_add_clk(), which allows to specify the struct clk * directly.
The will will increment refcount on clock pointer, so the caller has
to use clk_put() on clock pointer when done.

Reviewed-by: Santosh Shilimkar 
Reviewed-by: Kevin Hilman 
Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Grygorii Strashko 
Reviewed-by: Dmitry Torokhov 
Signed-off-by: Rafael J. Wysocki

PM / clk: Fix crash in clocks management code if !CONFIG_PM_RUNTIME

2014-10-03T13:51:39+00:00

Unlike the clocks management code for runtime PM, the code used for
system suspend does not check the pm_clock_entry.status field.
If pm_clk_acquire() failed, ce->status will be PCE_STATUS_ERROR, and
ce->clk will be a negative error code (e.g. 0xfffffffe = -2 = -ENOENT).

Depending on the clock implementation, suspend or resume may crash with:

    Unable to handle kernel NULL pointer dereference at virtual address 00000026

(CCF clk_disable() has an IS_ERR_OR_NULL() check, while CCF clk_enable()
 only has a NULL check; pre-CCF implementations may behave differently)

While just checking for PCE_STATUS_ERROR would be sufficient, it doesn't
hurt to use the same state machine as is done for runtime PM, as this
makes the two versions more similar, and eligible for a future
consolidation.

Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Rafael J. Wysocki

drivers/base: delete non-required instances of include

2014-02-14T22:31:37+00:00

None of these files are actually using any __init type directives
and hence don't need to include .  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

Cc: Len Brown 
Signed-off-by: Paul Gortmaker 
Acked-by: Pavel Machek 
Acked-by: Rafael J. Wysocki 
Acked-by: Mark Brown 
Signed-off-by: Greg Kroah-Hartman

PM / clock_ops: report clock errors from clk_enable()

2014-01-15T00:50:50+00:00

If clk_enable() fails, then print a message so that the user can see
what is happening instead of silently failing to enable the clock.

Signed-off-by: Ben Dooks 
Reviewed-by: Ian Molton 
Signed-off-by: Rafael J. Wysocki

PM / clock_ops: check return of clk_enable() in pm_clk_resume()

2014-01-15T00:50:50+00:00

The clk_enable() call in the pm_clk_resume() call returns an error
that is not being checked. If clk_enable() fails then we should
not set the state of the clock to PCE_STATUS_ENABLED.

Note, the issue of warning the user if this fails has not been
addressed in this patch as this is not the only place the driver
calls clk_enable().

Signed-off-by: Ben Dooks 
Reviewed-by: Ian Molton 
Signed-off-by: Rafael J. Wysocki

PM / clock_ops: fix up clk prepare/unprepare count

2014-01-15T00:50:50+00:00

The drivers/base/power/clock_ops.c file is causing warnings from
the clock driver (as shown below) due to failing to do a clk_prepare()
call before enabling a clock. It also fails to check the balance of
prepare/unprepare as __pm_clk_remove() do clk_disable_unprepare() call.

This bug has probably been in since commit b2476490e ("clk: introduce
the common clock framework") as the warning was part of the original
commit. It is strange that it has not been noticed (although this has
also been coupled with a failure for certain SH builds to not build the
necessary glue to use this method of controlling the clocks).

In summary, this is probably needed in several stable branches but need
advice on which ones.

On the Renesas Lager board, this causes numerous warnings of the following
and even worse the clock system will not enable clocks, causing drivers
that are in development to fail to work:

WARNING: CPU: 0 PID: 1 at drivers/clk/clk.c:883 __clk_enable+0x2c/0xa0()

Signed-off-by: Ben Dooks 
Reviewed-by: Ian Molton 
Signed-off-by: Rafael J. Wysocki

base: power - use clk_prepare_enable and clk_prepare_disable

2012-11-14T23:36:43+00:00

When PM runtime is enabled in DaVinci and the machine migrates to
common clk framework, the clk_enable() gets called without
clk_prepare(). This patch is to fix this issue so that PM run
time can inter work with common clk framework.

Signed-off-by: Murali Karicheri 
Signed-off-by: Rafael J. Wysocki

PM: Make dev_pm_get_subsys_data() always return 0 on success

2012-08-08T18:49:33+00:00

Commits 1d5fcfec22 (PM / Domains: Add device domain data reference
counter) and 62d4490294 (PM / Domains: Allow device callbacks to be
added at any time) added checks for the return value of
dev_pm_get_subsys_data(), but those checks were incorrect, because
that function returned 1 on success in some cases.

Since all of the existing users of dev_pm_get_subsys_data() don't use
the positive value returned by it on success, change its definition
so that it always returns 0 when successful.

Reported-by: Heiko Stübner 
Reported-by: Tushar Behera 
Signed-off-by: Rafael J. Wysocki