of_clk_get_by_clkspec() has the same function signature as
of_clk_get_from_provider()

 struct clk *of_clk_get_by_clkspec(struct of_phandle_args
 *clkspec)
 struct clk *of_clk_get_from_provider(struct of_phandle_args
 *clkspec)

except of_clk_get_by_clkspec() checks to make sure clkspec is not
NULL. Let's remove of_clk_get_by_clkspec() and replace the
callers of it (clkconf.c) with of_clk_get_from_provider().

Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: NTomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>

of_clk_get_by_clkspec() returns a struct clk pointer but it
doesn't create a new handle for the consumers when we're using
the common clock framework. Instead it just returns whatever the
clk provider hands out. When the consumers go to call clk_put()
we get an Oops.

Unable to handle kernel paging request at virtual address 00200200
pgd = c0004000
[00200200] *pgd=00000000
Internal error: Oops: 805 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.19.0-rc1-00104-ga251361a-dirty #992
Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
task: ee00b000 ti: ee088000 task.ti: ee088000
PC is at __clk_put+0x24/0xd0
LR is at clk_prepare_lock+0xc/0xec
pc : [<c03eef38>]    lr : [<c03ec1f4>]    psr: 20000153
sp : ee089de8  ip : 00000000  fp : 00000000
r10: ee02f480  r9 : 00000001  r8 : 00000000
r7 : ee031cc0  r6 : ee089e08  r5 : 00000000  r4 : ee02f480
r3 : 00100100  r2 : 00200200  r1 : 0000091e  r0 : 00000001
Flags: nzCv  IRQs on  FIQs off  Mode SVC_32  ISA ARM  Segment kernel
Control: 10c5387d  Table: 4000404a  DAC: 00000015
Process swapper/0 (pid: 1, stack limit = 0xee088238)
Stack: (0xee089de8 to 0xee08a000)
9de0:                   ee7c8f14 c03f0ec8 ee089e08 00000000 c0718dc8 00000001
9e00: 00000000 c04ee0f0 ee7e0844 00000001 00000181 c04edb58 ee2bd320 00000000
9e20: 00000000 c011dc5c ee16a1e0 00000000 00000000 c0718dc8 ee16a1e0 ee2bd1e0
9e40: c0641740 ee16a1e0 00000000 ee2bd320 c0718dc8 ee1d3e10 ee1d3e10 00000000
9e60: c0769a88 00000000 c0718dc8 00000000 00000000 c02c3124 c02c310c ee1d3e10
9e80: c07b4eec 00000000 c0769a88 c02c1d0c ee1d3e10 c0769a88 ee1d3e44 00000000
9ea0: c07091dc c02c1eb8 00000000 c0769a88 c02c1e2c c02c0544 ee005478 ee1676c0
9ec0: c0769a88 ee3a4e80 c0760ce8 c02c150c c0669b90 c0769a88 c0746cd8 c0769a88
9ee0: c0746cd8 ee2bc4c0 c0778c00 c02c24e0 00000000 c0746cd8 c0746cd8 c07091f0
9f00: 00000000 c0008944 c04f405c 00000025 ee00b000 60000153 c074ab00 00000000
9f20: 00000000 c074ab90 60000153 00000000 ef7fca5d c050860c 000000b6 c0036b88
9f40: c065ecc4 c06bc728 00000006 00000006 c074ab30 ef7fca40 c0739bdc 00000006
9f60: c0718dbc c0778c00 000000b6 c0718dc8 c06ed598 c06edd64 00000006 00000006
9f80: c06ed598 c003b438 00000000 c04e64f4 00000000 00000000 00000000 00000000
9fa0: 00000000 c04e64fc 00000000 c000e838 00000000 00000000 00000000 00000000
9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 c0c0c0c0 c0c0c0c0
[<c03eef38>] (__clk_put) from [<c03f0ec8>] (of_clk_set_defaults+0xe0/0x2c0)
[<c03f0ec8>] (of_clk_set_defaults) from [<c02c3124>] (platform_drv_probe+0x18/0xa4)
[<c02c3124>] (platform_drv_probe) from [<c02c1d0c>] (driver_probe_device+0x10c/0x22c)
[<c02c1d0c>] (driver_probe_device) from [<c02c1eb8>] (__driver_attach+0x8c/0x90)
[<c02c1eb8>] (__driver_attach) from [<c02c0544>] (bus_for_each_dev+0x54/0x88)
[<c02c0544>] (bus_for_each_dev) from [<c02c150c>] (bus_add_driver+0xd4/0x1d0)
[<c02c150c>] (bus_add_driver) from [<c02c24e0>] (driver_register+0x78/0xf4)
[<c02c24e0>] (driver_register) from [<c07091f0>] (fimc_md_init+0x14/0x30)
[<c07091f0>] (fimc_md_init) from [<c0008944>] (do_one_initcall+0x80/0x1d0)
[<c0008944>] (do_one_initcall) from [<c06edd64>] (kernel_init_freeable+0x108/0x1d4)
[<c06edd64>] (kernel_init_freeable) from [<c04e64fc>] (kernel_init+0x8/0xec)
[<c04e64fc>] (kernel_init) from [<c000e838>] (ret_from_fork+0x14/0x3c)
Code: ebfff4ae e5943014 e5942018 e3530000 (e5823000)

Let's create a per-user handle here so that clk_put() can
properly unlink it and free the handle. Now that we allocate a
clk structure here we need to free it if __clk_get() fails so
bury the __clk_get() call in __of_clk_get_from_provider(). We
need to handle the same problem in clk_get_sys() so export
__clk_free_clk() to clkdev.c and do the same thing, except let's
use a union to make this code #ifdef free.

This fixes the above crash, properly calls __clk_get() when
of_clk_get_from_provider() is called, and cleans up the clk
structure on the error path of clk_get_sys().

Fixes: 035a61c3 "clk: Make clk API return per-user struct clk instances"
Reported-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Reported-by: NAlban Browaeys <alban.browaeys@gmail.com>
Tested-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: NAlban Browaeys <prahal@yahoo.com>
Reviewed-by: NTomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NMichael Turquette <mturquette@linaro.org>

So it can be used from modules such as clk-test.ko.
Signed-off-by: NTomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NMichael Turquette <mturquette@linaro.org>

Moves clock state to struct clk_core, but takes care to change as little API as
possible.

struct clk_hw still has a pointer to a struct clk, which is the
implementation's per-user clk instance, for backwards compatibility.

The struct clk that clk_get_parent() returns isn't owned by the caller, but by
the clock implementation, so the former shouldn't call clk_put() on it.

Because some boards in mach-omap2 still register clocks statically, their clock
registration had to be updated to take into account that the clock information
is stored in struct clk_core now.
Signed-off-by: NTomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Tested-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NMichael Turquette <mturquette@linaro.org>
[mturquette@linaro.org: adapted clk_has_parent to struct clk_core
                        applied OMAP3+ DPLL fix from Tero & Tony]

This error message can spam the logs if you have lots of probe
deferals due to missing clocks. Just silence the error in this
case because the driver should try again later.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

This patch adds of_clk_get_by_clkspec() helper function, which does only
a struct clk lookup from the clock providers. It is used in the subsequent
patch where parsing of a clock from device tree and the lookup from
providers needed to be split.
Signed-off-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

At probe time, a clock device may not be ready when some other device
wants to use it.

This patch lets the functions clk_get/devm_clk_get return a probe defer
when the clock is defined in the DT but not yet available.
Signed-off-by: NJean-Francois Moine <moinejf@free.fr>
Reviewed-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

There is currently a race condition in the device tree part of clk_get()
function, since the pointer returned from of_clk_get_by_name() may become
invalid before __clk_get() call. E.g. due to the clock provider driver
remove() callback being called in between of_clk_get_by_name() and
__clk_get().

Fix this by doing both the look up and __clk_get() operations with the
clock providers list mutex held. This ensures that the clock pointer
returned from __of_clk_get_from_provider() call and passed to __clk_get()
is valid, as long as the clock supplier module first removes its clock
provider instance and then does clk_unregister() on the corresponding
clocks.
Signed-off-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: NMike Turquette <mturquette@linaro.org>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The managed clk functions are currently only available when the generic clk
lookup framework is build. But the managed clk functions are merely wrappers
around clk_get and clk_put and do not depend on any specifics of the generic
lookup functions and there are still quite a few custom implementations of the
clk API. So make the managed functions available whenever the clk API is
implemented.

The patch also removes the custom implementation of devm_clk_get for the
coldfire platform.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Acked-by: NGreg Ungerer <gerg@uclinux.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

With commit 766e6a4e (clk: add DT clock binding support),
compiling with OF && !COMMON_CLK is broken.
Reported-by: NAlexandre Pereira da Silva <aletes.xgr@gmail.com>
Reported-by: NPrashant Gaikwad <pgaikwad@nvidia.com>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

The commit 766e6a4e (clk: add DT clock binding support) plugs device
tree clk lookup of_clk_get_by_name into clk_get, and fall on non-DT
lookup clk_get_sys if DT lookup fails.

The return check on of_clk_get_by_name takes (clk != NULL) as a
successful DT lookup.  But it's not the case.  For any system that
does not define clk lookup in device tree, ERR_PTR(-ENOENT) will be
returned, and consequently, all the client drivers calling clk_get
in their probe functions will fail to probe with error code -ENOENT
returned.

Fix the issue by checking of_clk_get_by_name return with !IS_ERR(clk),
and update of_clk_get and of_clk_get_by_name for !CONFIG_OF build
correspondingly.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Acked-by: NRob Herring <rob.herring@calxeda.com>
Tested-by: NMarek Vasut <marex@denx.de>
Tested-by: NLauri Hintsala <lauri.hintsala@bluegiga.com>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

Based on work 1st by Ben Herrenschmidt and Jeremy Kerr, then by Grant
Likely, this patch adds support to clk_get to allow drivers to retrieve
clock data from the device tree.

Platforms scan for clocks in DT with of_clk_init and a match table, and
the register a provider through of_clk_add_provider. The provider's
clk_src_get function will be called when a device references the
provider's OF node for a clock reference.

v6 (Rob Herring):
    - Return error values instead of NULL to match clock framework
      expectations

v5 (Rob Herring):
    - Move from drivers/of into common clock subsystem
    - Squashed "dt/clock: add a simple provider get function" and
      "dt/clock: add function to get parent clock name"
    - Rebase to 3.4-rc1
    - Drop CONFIG_OF_CLOCK and just use CONFIG_OF
    - Add missing EXPORT_SYMBOL to various functions
    - s/clock-output-name/clock-output-names/
    - Define that fixed-clock binding is a single output

v4 (Rob Herring):
    - Rework for common clk subsystem
    - Add of_clk_get_parent_name function

v3: - Clarified documentation

v2: - fixed errant ';' causing compile error
    - Editorial fixes from Shawn Guo
    - merged in adding lookup to clkdev
    - changed property names to match established convention. After
      working with the binding a bit it really made more sense to follow the
      lead of 'reg', 'gpios' and 'interrupts' by making the input simply
      'clocks' & 'clock-names' instead of 'clock-input-*', and to only use
      clock-output* for the producer nodes. (Sorry Shawn, this will mean
      you need to change some code, but it should be trivial)
    - Add ability to inherit clocks from parent nodes by using an empty
      'clock-ranges' property.  Useful for busses.  I could use some feedback
      on the new property name, 'clock-ranges' doesn't feel right to me.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Reviewed-by: NShawn Guo <shawn.guo@freescale.com>
Cc: Sascha Hauer <kernel@pengutronix.de>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

The common clock framework allocates clocks dynamically.  Provide a
set of helpers to streamline the clkdev registration of the clock
lookups to avoid repetitive code sequences.
Reviewed-by: NViresh Kumar <viresh.kumar@st.com>
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

clk_find must return as soon as it gets the correct clock. Currently it check
all clocks until it found a lookup with both dev_id and con_id matching.

If only one of them is passed, then we don't actually need to wait for both of
them to match. We can quit as soon as the requested id (dev_id or con_id)
matches.
Signed-off-by: NViresh Kumar <viresh.kumar@st.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Allow clk API users to simplify their cleanup paths by providing a
managed version of clk_get() and clk_put().
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

clkdev may incorrectly cause a clkdev entry with a NULL clk to return
-ENOENT.  This is not the intention of this code; -ENOENT should only
be returned if the clock entry can not be found in the table.  Fix
this.
Reported-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

factorise some generic infrastructure to assist looking up struct clks
for the ARM & SH architecture.

as the code is identical at 99%

put the arch specific code for allocation as example in asm/clkdev.h
Signed-off-by: NJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: NPaul Mundt <lethal@linux-sh.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

clk_find function looks for clock with matching dev_id and con_id.
We should return from clk_find as soon as we get a clock with matching
dev_id and con_id. This can be done by comparing variable "match" with 3.
Acked-by: NUwe Kleine-Konig <u.kleine-koenig@pengutronix.de>
Signed-off-by: NViresh Kumar <viresh.kumar@st.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Most machine classes want some way to register a block of clk_lookup
structures, and most do it by implementing a clks_register() type
function which walks an array, or by open-coding a loop.

Consolidate all this into clkdev_add_table().
Acked-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: NKevin Hilman <khilman@deeprootsystems.com>
Acked-by: NEric Miao <eric.y.miao@gmail.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch was generated by

	git grep -E -i -l 'precidence' | xargs -r perl -p -i -e 's/precidence/precedence/'
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

<linux/clk.h> should be included to get the base API prototypes.

This fixes the following sparse warnings:

  arch/arm/common/clkdev.c:65:12:
    warning: symbol 'clk_get_sys' was not declared. Should it be static?

  arch/arm/common/clkdev.c:79:12:
    warning: symbol 'clk_get' was not declared. Should it be static?

  arch/arm/common/clkdev.c:87:6:
    warning: symbol 'clk_put' was not declared. Should it be static?
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This can be used for other arm platforms too as discussed
on the linux-arm-kernel list.

Also check the return value with IS_ERR and return PTR_ERR
as suggested by Russell King.
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This adds clk_get_sys to get a clock without the associated struct
device.
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>

The old matching algorithm was too fuzzy, causing false positives.
For example, when asked for device D connection C1 and we only find
device D connection C2, we return that as a valid match despite the
connection names being different.

Change the algorithm such that:
  An entry with a NULL ID is assumed to be a wildcard.
  If an entry has a device ID, it must match
  If an entry has a connection ID, it must match

However, we maintain the order of precidence while still only doing
a single pass over all entries: dev+con > dev only > con only.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add some generic infrastructure to assist looking up struct clks
for the ARM architecture.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>