kernel/linux.git/drivers/base/power/clock_ops.c, branch v3.18.76

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

device.h: cleanup users outside of linux/include (C files)

2012-03-11T18:27:37+00:00

For files that are actively using linux/device.h, make sure that they call it out. This will allow us to clean up some of the implicit uses of linux/device.h within include/* without introducing build regressions. Yes, this was created by "cheating" -- i.e. the headers were cleaned up, and then the fallout was found and fixed, and then the two commits were reordered. This ensures we don't introduce build regressions into the git history. Signed-off-by: Paul Gortmaker

PM / Clocks: Only disable enabled clocks in pm_clk_suspend()

2011-11-09T23:44:10+00:00

Refrain from running clk_disable() on clocks that have not been enabled. A typical case when this can happen is during Suspend-to-RAM for devices that have no driver associated with them. In such case the clock may be in default ACQUIRED state. Without this patch the sh7372 Mackerel board crashes in __clk_disable() during Suspend-to-RAM with: "Trying to disable clock 0xdeadbeef with 0 usecount" This happens for the CEU device which is added during boot. The test case has no CEU driver included in the kernel configuration. Needed for v3.2-rc1. Signed-off-by: Magnus Damm Signed-off-by: Rafael J. Wysocki

PM / Clocks: Remove redundant NULL checks before kfree()

2011-10-21T22:22:54+00:00

Since kfree() checks it its argument is not NULL, it is not necessary to duplicate this check in __pm_clk_remove(). [rjw: Added the changelog.] Signed-off-by: Jonghwan Choi Signed-off-by: Rafael J. Wysocki