Commit Graph

31 Commits

Author SHA1 Message Date
Bartosz Golaszewski
53ccb22b8d ARM: 8778/1: clkdev: don't call __of_clk_get_by_name() unnecessarily from clk_get()
The way this function is implemented caused some confusion when
converting the TI DaVinci platform to using the common clock framework.

Current kernel supports booting DaVinci boards both in device tree as
well as legacy, board-file mode. In the latter, we always end up
calling clk_get_sys() as of_node is NULL and __of_clk_get_by_name()
returns -ENOENT.

It was not obvious at first glance how clk_get(dev, NULL) will work in
board-file mode since we always call __of_clk_get_by_name(). Let's make
it clearer by checking if of_node is NULL and skipping right to
clk_get_sys().

Cc: Sekhar Nori <nsekhar@ti.com>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: David Lechner <david@lechnology.com>
Reviewed-by: David Lechner <david@lechnology.com>
Reviewed-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-08-13 16:27:52 +01:00
Geert Uytterhoeven
76672e2e5b ARM: 8776/1: clkdev: Remove duplicated negative index check from __of_clk_get()
__of_clk_get() calls of_parse_phandle_with_args(), which rejects
negative indices since commit bd69f73f2c ("of: Create function for
counting number of phandles in a property").

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-07-11 11:02:48 +01:00
Stephen Boyd
0d4e3d005c clk: Prepare to remove asm-generic/clkdev.h
Now that all the users of asm/clkdev.h have been replaced with
the generic file we can get rid of the asm-generic file as well
and implement that code directly where it's used.

We only have one caller of __clkdev_alloc(), in clkdev.c so we
can easily remove that and drop the include of asm/clkdev.h in
linux/clkdev.h by putting the __clk_get/__clk_put inlines in
their respective location.

Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2018-01-02 16:12:00 -08:00
Rob Herring
1667393126 clk: Convert to using %pOF instead of full_name
Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: "Emilio López" <emilio@elopez.com.ar>
Cc: Peter De Schrijver <pdeschrijver@nvidia.com>
Cc: Prashant Gaikwad <pgaikwad@nvidia.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Tero Kristo <t-kristo@ti.com>
Cc: linux-clk@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-renesas-soc@vger.kernel.org
Cc: linux-tegra@vger.kernel.org
Cc: linux-omap@vger.kernel.org
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: James Liao <jamesjj.liao@mediatek.com>
Acked-by: Alexandre TORGUE <alexandre.torgue@st.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2017-07-21 15:49:54 -07:00
Geert Uytterhoeven
9388093db4 ARM: 8631/1: clkdev: Detect errors in clk_hw_register_clkdev() for mass registration
Unlike clk_register_clkdev(), clk_hw_register_clkdev() doesn't check for
passed error objects from a previous registration call. Hence the caller
of clk_hw_register_*() has to check for errors before calling
clk_hw_register_clkdev*().

Make clk_hw_register_clkdev() more similar to clk_register_clkdev() by
adding this error check, removing the burden from callers that do mass
registration.

Fixes: e4f1b49bda ("clkdev: Add clk_hw based registration APIs")
Fixes: 944b9a41e0 ("clk: ls1x: Migrate to clk_hw based OF and registration APIs")
Fixes: 44ce9a9ae9 ("MIPS: TXx9: Convert to Common Clock Framework")
Fixes: f48d947a16 ("clk: clps711x: Migrate to clk_hw based OF and registration APIs")
Fixes: b4626a7f48 ("CLK: Add Loongson1C clock support")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-11-22 11:45:28 +00:00
Fabian Frederick
bd721ea73e treewide: replace obsolete _refok by __ref
There was only one use of __initdata_refok and __exit_refok

__init_refok was used 46 times against 82 for __ref.

Those definitions are obsolete since commit 312b1485fb ("Introduce new
section reference annotations tags: __ref, __refdata, __refconst")

This patch removes the following compatibility definitions and replaces
them treewide.

/* compatibility defines */
#define __init_refok     __ref
#define __initdata_refok __refdata
#define __exit_refok     __ref

I can also provide separate patches if necessary.
(One patch per tree and check in 1 month or 2 to remove old definitions)

[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/1466796271-3043-1-git-send-email-fabf@skynet.be
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02 17:31:41 -04:00
Stephen Boyd
e4f1b49bda clkdev: Add clk_hw based registration APIs
Now that we have a clk registration API that doesn't return
struct clks, we need to have some way to hand out struct clks via
the clk_get() APIs that doesn't involve associating struct clk
pointers with a struct clk_lookup. Luckily, clkdev already
operates on struct clk_hw pointers, except for the registration
facing APIs where it converts struct clk pointers into struct
clk_hw pointers almost immediately.

Let's add clk_hw based registration APIs so that we can skip the
conversion step and provide a way for clk provider drivers to
operate exclusively on clk_hw structs. This way we clearly
split the API between consumers and providers.

Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-19 16:54:26 -07:00
Stephen Boyd
a14b9e0512 clkdev: Remove clk_register_clkdevs()
Now that we've converted the only caller over to another clkdev
API, remove this one.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-19 16:51:58 -07:00
Kees Cook
416dd13ad6 ARM: 8503/1: clk_register_clkdev: remove format string interface
Many callers either use NULL or const strings for the third argument of
clk_register_clkdev. For those that do not and use a non-const string,
this is a risk for format strings being accidentally processed (for
example in device names). As this interface is already used as if it
weren't a format string (prints nothing when NULL), and there are zero
users of the format strings, remove the format string interface to make
sure format strings will not leak into the clkdev.

$ git grep '\bclk_register_clkdev\b' | grep % | wc -l
0

Unfortunately, all the internals expect a va_list even though they treat
a NULL format string as special. To deal with this, we must pass either
(..., "%s", string) or (..., NULL) so that a the va_list will be created
correctly (passing the name as an argument, not as a format string).

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-02-16 16:34:18 +00:00
Russell King
625faa6a72 clkdev: fix clk_add_alias() with a NULL alias device name
clk_add_alias() was not correctly handling the case where alias_dev_name
was NULL: rather than producing an entry with a NULL dev_id pointer,
it would produce a device name of (null).  Fix this.

Cc: <stable@vger.kernel.org>
Fixes: 2568999835 ("clkdev: add clkdev_create() helper")
Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-10-20 17:24:08 +01:00
Russell King
2568999835 clkdev: add clkdev_create() helper
Add a helper to allocate and add a clk_lookup structure.  This can not
only be used in several places in clkdev.c to simplify the code, but
more importantly, can be used by callers of the clkdev code to simplify
their clkdev creation and registration.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-05-06 11:58:57 +01:00
Russell King
b3d8d7e89f clkdev: const-ify connection id to clk_add_alias()
The connection id is only passed to clk_get() which is already const.
Const-ify this argument too.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-05-06 11:58:57 +01:00
Russell King
fba3acd961 clkdev: drop __init from clkdev_add_table()
We want to be able to call clkdev_add_table() from non-init code, so we
need to drop the __init marker from it.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-05-06 11:58:10 +01:00
Russell King
d5622a9c13 clkdev: use clk_hw internally
clk_add_alias() calls clk_get() followed by clk_put() but in between
those two calls it saves away the struct clk pointer to a clk_lookup
structure. This leaves the 'clk' member of the clk_lookup pointing at
freed memory on configurations where CONFIG_COMMON_CLK=y. This is a
problem because clk_get_sys() will eventually try to dereference the
freed pointer by calling __clk_get_hw() on it. Fix this by saving away
the struct clk_hw pointer instead of the struct clk pointer so that when
we try to create a per-user struct clk in clk_get_sys() we don't
dereference a junk pointer.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-05-06 11:58:02 +01:00
Stephen Boyd
306c342f9c clk: Replace of_clk_get_by_clkspec() with of_clk_get_from_provider()
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: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-03-12 12:20:34 -07:00
Stephen Boyd
73e0e496af clkdev: Always allocate a struct clk and call __clk_get() w/ CCF
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: 035a61c314 "clk: Make clk API return per-user struct clk instances"
Reported-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reported-by: Alban Browaeys <alban.browaeys@gmail.com>
Tested-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Alban Browaeys <prahal@yahoo.com>
Reviewed-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-02-06 17:53:20 -08:00
Tomeu Vizoso
a251361ac4 clkdev: Export clk_register_clkdev
So it can be used from modules such as clk-test.ko.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-02-02 14:23:43 -08:00
Tomeu Vizoso
035a61c314 clk: Make clk API return per-user struct clk instances
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: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
[mturquette@linaro.org: adapted clk_has_parent to struct clk_core
                        applied OMAP3+ DPLL fix from Tero & Tony]
2015-02-02 14:22:19 -08:00
Stephen Boyd
d8e53c3deb clkdev: Don't print errors on probe defer
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: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-06-26 12:55:03 -07:00
Sylwester Nawrocki
7f05e28f9d clk: Add of_clk_get_by_clkspec() helper
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: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-05-22 15:54:59 -07:00
Jean-Francois Moine
a34cd4666f clk: return probe defer when DT clock not yet ready
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: Jean-Francois Moine <moinejf@free.fr>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-02-24 17:14:56 -08:00
Sylwester Nawrocki
3a3d2b0551 clkdev: Fix race condition in clock lookup from device tree
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: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Mike Turquette <mturquette@linaro.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-12-04 17:19:36 +01:00
Lars-Peter Clausen
8ef997b67f ARM: 7534/1: clk: Make the managed clk functions generically available
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: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-09-15 21:55:27 +01:00
Rob Herring
137f8a7213 clk: fix compile for OF && !COMMON_CLK
With commit 766e6a4ec6 (clk: add DT clock binding support),
compiling with OF && !COMMON_CLK is broken.

Reported-by: Alexandre Pereira da Silva <aletes.xgr@gmail.com>
Reported-by: Prashant Gaikwad <pgaikwad@nvidia.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2012-07-19 14:07:56 -07:00
Shawn Guo
9f1612d351 clk: fix clk_get on of_clk_get_by_name return check
The commit 766e6a4 (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: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Tested-by: Marek Vasut <marex@denx.de>
Tested-by: Lauri Hintsala <lauri.hintsala@bluegiga.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2012-07-19 14:07:45 -07:00
Grant Likely
766e6a4ec6 clk: add DT clock binding support
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: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Reviewed-by: Shawn Guo <shawn.guo@freescale.com>
Cc: Sascha Hauer <kernel@pengutronix.de>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2012-07-11 17:58:45 -07:00
Russell King
e9d7f40654 CLKDEV: provide helpers for common clock framework
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: Viresh Kumar <viresh.kumar@st.com>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-05-02 09:30:32 +01:00
viresh kumar
67b508715a ARM: 7392/1: CLKDEV: Optimize clk_find()
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: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-04-19 19:34:26 +01:00
Mark Brown
a8a97db984 ARM: 7376/1: clkdev: Implement managed clk_get()
Allow clk API users to simplify their cleanup paths by providing a
managed version of clk_get() and clk_put().

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-04-19 19:34:18 +01:00
Russell King
e8bf8df9c2 CLKDEV: Fix clkdev return value for NULL clk case
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: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-04-30 10:14:08 +01:00
Jean-Christop PLAGNIOL-VILLARD
6d803ba736 ARM: 6483/1: arm & sh: factorised duplicated clkdev.c
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: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-11-26 10:51:04 +00:00