Add support for DT "fixed-clock" binding to the common fixed rate clock
support.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
[Rob Herring] Rework and move into common clock infrastructure
Signed-off-by: NRob Herring <rob.herring@calxeda.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>

Allow drivers to declare their clk_init_data const, the framework really
shouldn't be modifying the data.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

Most platforms end up using a mix of basic clock types and
some which use clk_hw_foo struct for filling in custom platform
information when the clocks don't fit into basic types supported.

In platform code, its useful to know if a clock is using a basic
type or clk_hw_foo, which helps platforms know if they can
safely use to_clk_hw_foo to derive the clk_hw_foo pointer from
clk_hw.

Mark all basic clocks with a CLK_IS_BASIC flag.
Signed-off-by: NRajendra Nayak <rnayak@ti.com>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

Some divider clks do not have any obvious relationship
between the divider and the value programmed in the
register. For instance, say a value of 1 could signify divide
by 6 and a value of 2 could signify divide by 4 etc.
Also there are dividers where not all values possible
based on the bitfield width are valid. For instance
a 3 bit wide bitfield can be used to program a value
from 0 to 7. However its possible that only 0 to 4
are valid values.

All these cases need the platform code to pass a simple
table of divider/value tuple, so the framework knows
the exact value to be written based on the divider
calculation and can also do better error checking.

This patch adds support for such rate table based
dividers and as part of the support adds a new
registration function 'clk_register_divider_table()'
and a new macro for static definition
'DEFINE_CLK_DIVIDER_TABLE'.
Signed-off-by: NRajendra Nayak <rnayak@ti.com>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

While there's no actual implementation behind it having the call to use
in drivers makes them feel neater from a driver author point of view. An
actual implementation can wait for someone who needs to use the function
in a real system.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
[mturquette@linaro.org: void return type instead of int -EINVAL]
Signed-off-by: NMike Turquette <mturquette@linaro.org>

Having fixed factors/dividers in hardware is a common pattern, so
add a basic clock type doing this. It basically describes a fixed
factor clock using a nominator and a denominator.
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: NViresh Kumar <viresh.kumar@st.com>
Tested-by: NShawn Guo <shawn.guo@linaro.org>
[mturquette@linaro.org: constify parent_names in static init macro]
[mturquette@linaro.org: copy/paste bug from mux in static init macro]
[mturquette@linaro.org: fix error handling in clk_register_fixed_factor]
[mturquette@linaro.org: improve division accuracy; thanks to Saravana]
Signed-off-by: NMike Turquette <mturquette@linaro.org>

Create a struct clk_init_data to hold all data that needs to be passed from
the platfrom specific driver to the common clock framework during clock
registration. Add a pointer to this struct inside clk_hw.

This has several advantages:
* Completely hides struct clk from many clock platform drivers and static
  clock initialization code that don't care for static initialization of
  the struct clks.
* For platforms that want to do complete static initialization, it removed
  the need to directly mess with the struct clk's fields while still
  allowing to statically allocate struct clk. This keeps the code more
  future proof even if they include clk-private.h.
* Simplifies the generic clk_register() function and allows adding optional
  fields in the future without modifying the function signature.
* Simplifies the static initialization of clocks on all platforms by
  removing the need for forward delcarations or convoluted macros.
Signed-off-by: NSaravana Kannan <skannan@codeaurora.org>
[mturquette@linaro.org: kept DEFINE_CLK_* macros and __clk_init]
Signed-off-by: NMike Turquette <mturquette@linaro.org>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jeremy Kerr <jeremy.kerr@canonical.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergman <arnd.bergmann@linaro.org>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Shawn Guo <shawn.guo@freescale.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Jamie Iles <jamie@jamieiles.com>
Cc: Richard Zhao <richard.zhao@linaro.org>
Cc: Saravana Kannan <skannan@codeaurora.org>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Amit Kucheria <amit.kucheria@linaro.org>
Cc: Deepak Saxena <dsaxena@linaro.org>
Cc: Grant Likely <grant.likely@secretlab.ca>

CLK_MUX_INDEX_BIT is mistakenly written as CLK_MUX_INDEX_BITWISE in comment. Fix
it.

CLK_GATE_SET_TO_DISABLE is mistakenly written as CLK_GATE_SET_DISABLE in
comment. Fix it.
Signed-off-by: NViresh Kumar <viresh.kumar@st.com>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

For most of .set_rate implementation, parent_rate will be used, so just
like passing parent_rate into .recalc_rate, let's pass parent_rate into
.set_rate too.

It also updates the kernel doc for .set_rate ops.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

This patch is the basic clk version of 'clk: core: copy parent_names &
return error codes'.

The registration functions are changed to allow the core code to copy
the array of strings and allow platforms to declare those arrays as
__initdata.

This patch also converts all of the basic clk registration functions to
return error codes which better aligns them with the existing clk.h api.
Signed-off-by: NMike Turquette <mturquette@linaro.org>

This patch cleans up clk_register and solves a few bugs by teaching
clk_register and __clk_init to return error codes (instead of just NULL)
to better align with the existing clk.h api.

Along with that change this patch also introduces a new behavior whereby
clk_register copies the parent_names array, thus allowing platforms to
declare their parent_names arrays as __initdata.
Signed-off-by: NMike Turquette <mturquette@linaro.org>

Drivers should be able to declare their arrays of parent names as const
so the APIs need to accept const arguments.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
[mturquette@linaro.org: constified gate]
Signed-off-by: NMike Turquette <mturquette@linaro.org>

Besides the static initialization, the clk_ops of basic clks could
also be used by particular clk type being subclass of the basic clks.

For example, clk_busy_divider has the same clk_ops as clk_divider,
except it has to wait for a busy bit before return success with
.set_rate.  clk_busy_divider will somehow reuse clk_ops of clk_divider.

Since clk-provider.h is included by clk-private.h, it's safe to move
those clk_ops declaration of basic clks form  clk-private.h into
clk-provider.h, so that implementation of clks like clk_busy_divider
above do not need to include clk-private.h to access those clk_ops.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

Many platforms support simple gateable clocks, fixed-rate clocks,
adjustable divider clocks and multi-parent multiplexer clocks.

This patch introduces basic clock types for the above-mentioned hardware
which share some common characteristics.

Based on original work by Jeremy Kerr and contribution by Jamie Iles.
Dividers and multiplexor clocks originally contributed by Richard Zhao &
Sascha Hauer.
Signed-off-by: NMike Turquette <mturquette@linaro.org>
Signed-off-by: NMike Turquette <mturquette@ti.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Tested-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NRob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jeremy Kerr <jeremy.kerr@canonical.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergman <arnd.bergmann@linaro.org>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Shawn Guo <shawn.guo@freescale.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Jamie Iles <jamie@jamieiles.com>
Cc: Richard Zhao <richard.zhao@linaro.org>
Cc: Saravana Kannan <skannan@codeaurora.org>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Amit Kucheria <amit.kucheria@linaro.org>
Cc: Deepak Saxena <dsaxena@linaro.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

The common clock framework defines a common struct clk useful across
most platforms as well as an implementation of the clk api that drivers
can use safely for managing clocks.

The net result is consolidation of many different struct clk definitions
and platform-specific clock framework implementations.

This patch introduces the common struct clk, struct clk_ops and an
implementation of the well-known clock api in include/clk/clk.h.
Platforms may define their own hardware-specific clock structure and
their own clock operation callbacks, so long as it wraps an instance of
struct clk_hw.

See Documentation/clk.txt for more details.

This patch is based on the work of Jeremy Kerr, which in turn was based
on the work of Ben Herrenschmidt.
Signed-off-by: NMike Turquette <mturquette@linaro.org>
Signed-off-by: NMike Turquette <mturquette@ti.com>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: Rob Herring <rob.herring <at> calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jeremy Kerr <jeremy.kerr@canonical.com>
Cc: Arnd Bergman <arnd.bergmann@linaro.org>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Shawn Guo <shawn.guo@freescale.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Richard Zhao <richard.zhao@linaro.org>
Cc: Saravana Kannan <skannan@codeaurora.org>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Amit Kucheria <amit.kucheria@linaro.org>
Cc: Deepak Saxena <dsaxena@linaro.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>