clk: ti: Improve clksel clock bit parsing for reg property

Because of legacy reasons, the TI clksel composite clocks can have
overlapping reg properties, and use a custom ti,bit-shift property.

For the clksel clocks we can start using of the standard reg property
instead of the custom ti,bit-shift property.

To do this, let's add a ti_clk_get_legacy_bit_shift() helper, and make
ti_clk_get_reg_addr() populate the clock bit offset.

This makes it possible to update the devicetree files to use the reg
property one clock at a time.

Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>

clk: ti: fix double free in of_ti_divider_clk_setup()

The "div" pointer is freed in _register_divider() and again in
of_ti_divider_clk_setup(). Delete the free in _register_divider()

Fixes: fbbc18591585 ("clk: ti: divider: cleanup _register_divider and ti_clk_get_div_table")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/6d36eeec-6c8a-4f11-a579-aa3cd7c38749@moroto.mountain
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: ti: change ti_clk_register[_omap_hw]() API

The ti_clk_register() and ti_clk_register_omap_hw() functions are always
called with the parameter of type "struct device" set to NULL, since the
functions from which they are called always have a parameter of type
"struct device_node". Replacing "struct device" type parameter with
"struct device_node" will allow you to register a TI clock to the common
clock framework by taking advantage of the facilities provided by the
"struct device_node" type. Further, adding the "of_" prefix to the name
of these functions explicitly binds them to the "struct device_node"
type.

The patch has been tested on a Beaglebone board.

Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20221113181147.1626585-1-dario.binacchi@amarulasolutions.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_320.RULE

Based on the normalized pattern:

this program is free software you can redistribute it and/or modify it
under the terms of the gnu general public license version 2 as
published by the free software foundation this program is distributed
as is without any warranty of any kind whether express or implied
without even the implied warranty of merchantability or fitness for a
particular purpose see the gnu general public license for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference.

Reviewed-by: Allison Randal <allison@lohutok.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

clk: ti: Update component clocks to use ti_dt_clk_name()

Let's update all the TI component clocks to use ti_dt_clk_name() instead
of devicetree node name if available.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20220204071449.16762-9-tony@atomide.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: ti: divider: convert to use min,max,mask instead of width

The existing width field used to check divider validity does not provide
enough protection against bad values. For example, if max divider value
is 4, the smallest all-1 bitmask that can hold this value is 7, which
allows values higher than 4 to be used. This typically causes
unpredictable results with hardware. So far this issue hasn't been
noticed as most of the dividers actually have maximum values which fit
the whole bitfield, but there are certain clocks for which this is a
problem, like dpll4_m4 divider on omap3 devices.

Thus, convert the whole validity logic to use min,max and mask values
for determining if a specific divider is valid or not. This prevents
the odd cases where bad value would otherwise be written to a divider
config register.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Tested-by: Adam Ford <aford173@gmail.com>

clk: ti: divider: cleanup ti_clk_parse_divider_data API

Cleanup the ti_clk_parse_divider_data to pass the divider data struct
directly instead of individual values of it. This makes it easier
to modify the implementation later on.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Tested-by: Adam Ford <aford173@gmail.com>

clk: ti: divider: cleanup _register_divider and ti_clk_get_div_table

Cleanup couple of TI divider clock internal APIs. These currently pass
huge amount of parameters, which makes it difficult to track what is
going on. Abstract most of these under struct clk_omap_div which gets
passed over the APIs.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Tested-by: Adam Ford <aford173@gmail.com>

clk: ti: Remove unused functions

They are not used any more since
commit 7558562a70fb ("clk: ti: Drop legacy clk-3xxx-legacy code")

Reported-by: Hulk Robot <hulkci@huawei.com>
Suggested-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: ti: remove usage of CLK_IS_BASIC

Remove the usage of CLK_IS_BASIC flag completely from TI clock driver.
In most cases, the use is completely redundant, but in some cases
we need to use the new API to check if the clock is an OMAP clock or not.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Tested-by: Keerthy <j-keerthy@ti.com>

clk: ti: Fix error handling in ti_clk_parse_divider_data()

The ti_clk_parse_divider_data() function is only called from
_get_div_table_from_setup(). That function doesn't look at the return
value but instead looks at the "*table" pointer. In this case, if the
kcalloc() fails then *table is NULL (which means success). It should
instead be an error pointer.

The ti_clk_parse_divider_data() function has two callers. One checks
for errors and the other doesn't. I have fixed it so now both handle
errors.

Fixes: 4f6be5655dc9 ("clk: ti: divider: add driver internal API for parsing divider data")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: ti: Add functions to save/restore clk context

SoCs like AM43XX lose clock registers context during RTC-only
suspend. Hence add functions to save/restore the clock registers
context.

Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Russ Dill <Russ.Dill@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>

clk: Convert to using %pOFn instead of device_node.name

In preparation to remove the node name pointer from struct device_node,
convert printf users to use the %pOFn format specifier.

Cc: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: linux-clk@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-renesas-soc@vger.kernel.org
Cc: linux-omap@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

treewide: kzalloc() -> kcalloc()

The kzalloc() function has a 2-factor argument form, kcalloc(). This
patch replaces cases of:

kzalloc(a * b, gfp)

with:
kcalloc(a * b, gfp)

as well as handling cases of:

kzalloc(a * b * c, gfp)

with:

kzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

kzalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

kzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
kzalloc(
- (sizeof(TYPE)) * E
+ sizeof(TYPE) * E
, ...)
|
kzalloc(
- (sizeof(THING)) * E
+ sizeof(THING) * E
, ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
kzalloc(
- sizeof(u8) * (COUNT)
+ COUNT
, ...)
|
kzalloc(
- sizeof(__u8) * (COUNT)
+ COUNT
, ...)
|
kzalloc(
- sizeof(char) * (COUNT)
+ COUNT
, ...)
|
kzalloc(
- sizeof(unsigned char) * (COUNT)
+ COUNT
, ...)
|
kzalloc(
- sizeof(u8) * COUNT
+ COUNT
, ...)
|
kzalloc(
- sizeof(__u8) * COUNT
+ COUNT
, ...)
|
kzalloc(
- sizeof(char) * COUNT
+ COUNT
, ...)
|
kzalloc(
- sizeof(unsigned char) * COUNT
+ COUNT
, ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kzalloc
+ kcalloc
(
- sizeof(TYPE) * (COUNT_ID)
+ COUNT_ID, sizeof(TYPE)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(TYPE) * COUNT_ID
+ COUNT_ID, sizeof(TYPE)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(TYPE) * (COUNT_CONST)
+ COUNT_CONST, sizeof(TYPE)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(TYPE) * COUNT_CONST
+ COUNT_CONST, sizeof(TYPE)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(THING) * (COUNT_ID)
+ COUNT_ID, sizeof(THING)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(THING) * COUNT_ID
+ COUNT_ID, sizeof(THING)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(THING) * (COUNT_CONST)
+ COUNT_CONST, sizeof(THING)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(THING) * COUNT_CONST
+ COUNT_CONST, sizeof(THING)
, ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kzalloc
+ kcalloc
(
- SIZE * COUNT
+ COUNT, SIZE
, ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
kzalloc(
- sizeof(TYPE) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
kzalloc(
- sizeof(TYPE) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
kzalloc(
- sizeof(TYPE) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
kzalloc(
- sizeof(TYPE) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
kzalloc(
- sizeof(THING) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
kzalloc(
- sizeof(THING) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
kzalloc(
- sizeof(THING) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
kzalloc(
- sizeof(THING) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
kzalloc(
- sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
kzalloc(
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
kzalloc(
- sizeof(THING1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
kzalloc(
- sizeof(THING1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
kzalloc(
- sizeof(TYPE1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
|
kzalloc(
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
kzalloc(
- (COUNT) * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
kzalloc(
- COUNT * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
kzalloc(
- COUNT * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
kzalloc(
- (COUNT) * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
kzalloc(
- COUNT * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
kzalloc(
- (COUNT) * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
kzalloc(
- (COUNT) * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
kzalloc(
- COUNT * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
kzalloc(C1 * C2 * C3, ...)
|
kzalloc(
- (E1) * E2 * E3
+ array3_size(E1, E2, E3)
, ...)
|
kzalloc(
- (E1) * (E2) * E3
+ array3_size(E1, E2, E3)
, ...)
|
kzalloc(
- (E1) * (E2) * (E3)
+ array3_size(E1, E2, E3)
, ...)
|
kzalloc(
- E1 * E2 * E3
+ array3_size(E1, E2, E3)
, ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
kzalloc(sizeof(THING) * C2, ...)
|
kzalloc(sizeof(TYPE) * C2, ...)
|
kzalloc(C1 * C2 * C3, ...)
|
kzalloc(C1 * C2, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(TYPE) * (E2)
+ E2, sizeof(TYPE)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(TYPE) * E2
+ E2, sizeof(TYPE)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(THING) * (E2)
+ E2, sizeof(THING)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(THING) * E2
+ E2, sizeof(THING)
, ...)
|
- kzalloc
+ kcalloc
(
- (E1) * E2
+ E1, E2
, ...)
|
- kzalloc
+ kcalloc
(
- (E1) * (E2)
+ E1, E2
, ...)
|
- kzalloc
+ kcalloc
(
- E1 * E2
+ E1, E2
, ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>

clk: ti: add support for clock latching to divider clocks

Latching the clock settings is needed with certain clocks, where
the setting is "cached" in HW before doing the actual re-programming
of the clock source. This patch adds support for clock latching to
the divider clock.

Signed-off-by: Tero Kristo <t-kristo@ti.com>

clk: ti: Delete error messages for failed memory allocations

Omit extra messages for a memory allocation failure in these
functions.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: ti: divider: try to fix ti_clk_register_divider

Commit 6c0afb503937 ("clk: ti: convert to use proper register
definition for all accesses") converted all register accesses in
the TI clk driver to use a proper struct instead of a void
pointer casted struct that fits into a u32. Unfortunately, it
missed a conversion here in the didivder code, leading to a
compiler warning like so:

drivers/clk/ti/divider.c: In function 'ti_clk_register_divider':
drivers/clk/ti/divider.c:460:8: error: 'reg' may be used uninitialized in this function [-Werror=maybe-uninitialized]

Treating a 'u32' variable as a structure leads to a stack
overflow here, and the register address we pass down is never
initialized. Convert this part of the code as well so things
work properly.

Fixes: 6c0afb503937 ("clk: ti: convert to use proper register definition for all accesses")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[sboyd@codeaurora.org: Fixed fixes tag, rewrote commit message,
s/reg_setup/reg/]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: ti: convert to use proper register definition for all accesses

Currently, TI clock driver uses an encapsulated struct that is cast into
a void pointer to store all register addresses. This can be considered
as rather nasty hackery, and prevents from expanding the register
address field also. Instead, replace all the code to use proper struct
in place for this, which contains all the previously used data.

This patch is rather large as it is touching multiple files, but this
can't be split up as we need to avoid any boot breakage.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>

clk: ti: divider: add driver internal API for parsing divider data

This can be used from the divider itself, and also from the clkctrl
clocks once this is introduced.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>

clk: ti: divider: convert TI divider clock to use its own data representation

Instead of using the generic clock driver data struct, use one internal
for the TI clock driver itself. This allows modifying the register access
parts in subsequent patch.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>

clk: ti: use automatic clock alias generation framework

Generate clock aliases automatically for all TI clock drivers.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>

clk: ti: divider: Add the table parsing to get the best divider value

Currently the divider selection logic blindly divides the parent_rate
by the clk rate and gives the divider value for the divider clocks
which do not have the CLK_SET_RATE_PARENT flag set. Add the clk divider
table parsing to get the closest divider available in the table
provided via Device tree.

The code is pretty much taken from: drivers/clk/clk-divider.c.
and used here to fix up the best divider selection logic.

Signed-off-by: Keerthy <j-keerthy@ti.com>
Reported-by: Richard Woodruff <r-woodruff2@ti.com>
Acked-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: move the common clock's to_clk_*(_hw) macros to clk-provider.h

to_clk_*(_hw) macros have been repeatedly defined in many places.
This patch moves all the to_clk_*(_hw) definitions in the common
clock framework to public header clk-provider.h, and drop the local
definitions.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: ti: drop locking code from mux/divider drivers

TI's mux and divider clock drivers do not require locking and they do
not initialize internal spinlocks. This code was occasionally
copy-posted from generic mux/divider drivers. So remove it.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>

clk: ti: Convert to clk_hw based provider APIs

We're removing struct clk from the clk provider API, so switch
this code to using the clk_hw based provider APIs.

Acked-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: Convert __clk_get_flags() to clk_hw_get_flags()

Mostly converted with the following snippet:

@@
struct clk_hw *E;
@@

-__clk_get_flags(E->clk)
+clk_hw_get_flags(E)

Acked-by: Tero Kristo <t-kristo@ti.com>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Coquelin <mcoquelin.stm32@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: ti: fix ti_clk_get_reg_addr error handling

There is a case where NULL can be a valid return value for
ti_clk_get_reg_addr, specifically the case where both the provider index
and register offsets are zero. In this case, the current error checking
against a NULL pointer will fail. Thus, change the API to return a
ERR_PTR value in an error case, and change all the users of this API to
check against IS_ERR instead.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Michael Turquette <mturquette@linaro.org>

clk: ti: divider: add support for legacy divider init

Legacy clock data is initialized slightly differently compared to
DT clocks, thus add support for this.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>

clk: ti: LLVMLinux: Move __init outside of type definition

As written, the __init for ti_clk_get_div_table is in the middle of the return
type.

The gcc documentation indicates that section attributes should be added to the
end of the function declaration:

extern void foobar (void) __attribute__ ((section ("bar")));

However gcc seems to be very permissive with where attributes can be placed.
clang on the other hand isn't so permissive, and fails if you put the section
definition in the middle of the return type:

drivers/clk/ti/divider.c:298:28: error: expected ';' after struct
static struct clk_div_table
^
;
drivers/clk/ti/divider.c:298:1: warning: 'static' ignored on this
declaration [-Wmissing-declarations]
static struct clk_div_table
^
drivers/clk/ti/divider.c:299:9: error: type specifier missing,
defaults to 'int' [-Werror,-Wimplicit-int]
__init *ti_clk_get_div_table(struct device_node *node)
~~~~~~ ^
drivers/clk/ti/divider.c:345:9: warning: incompatible pointer types
returning 'struct clk_div_table *' from a function with result type 'int *' [-Wincompatible-pointer-types]
return table;
^~~~~
drivers/clk/ti/divider.c:419:9: warning: incompatible pointer types
assigning to 'const struct clk_div_table *' from 'int *' [-Wincompatible-pointer-types]
*table = ti_clk_get_div_table(node);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~
3 warnings and 2 errors generated.

By convention, most of the kernel code puts section attributes between the
return type and function name. In the case where the return type is a pointer,
it's important to place the '*' on left of the __init.

This updated code works for both gcc and clang.

Signed-off-by: Behan Webster <behanw@converseincode.com>
Reviewed-by: Mark Charlebois <charlebm@gmail.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>

clk: ti: divider: Provide error check for incoming parameters in set_rate

Check for valid parameters in check rate. Else, we end up getting errors
like:
[ 0.000000] Division by zero in kernel.
[ 0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.17.0-rc1 #1
[ 0.000000] [<c0015160>] (unwind_backtrace) from [<c0011978>] (show_stack+0x10/0x14)
[ 0.000000] [<c0011978>] (show_stack) from [<c055f5f4>] (dump_stack+0x78/0x94)
[ 0.000000] [<c055f5f4>] (dump_stack) from [<c02e17cc>] (Ldiv0+0x8/0x10)
[ 0.000000] [<c02e17cc>] (Ldiv0) from [<c047d228>] (ti_clk_divider_set_rate+0x14/0x14c)
[ 0.000000] [<c047d228>] (ti_clk_divider_set_rate) from [<c047a938>] (clk_change_rate+0x138/0x180)
[ 0.000000] [<c047a938>] (clk_change_rate) from [<c047a908>] (clk_change_rate+0x108/0x180)

This occurs as part of the inital clock tree update of child clock nodes
where new_rate could be 0 for non functional clocks.

Fixes: b4761198bfaf296 ("CLK: ti: add support for ti divider-clock")
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>

clk: ti/divider: fix rate calculation for fractional rates

ti/clk-divider.c does not calculate the rates consistently at the moment.

As an example, on OMAP3 we have a clock divider with a source clock of
864000000 Hz. With dividers 6, 7 and 8 the theoretical rates are:

6: 144000000
7: 123428571.428571...
8: 108000000

Calling clk_round_rate() with the rate in the first column will give the
rate in the second column:

144000000 -> 144000000
143999999 -> 123428571
123428572 -> 123428571
123428571 -> 108000000

Note how clk_round_rate() returns 123428571 for rates from 123428572 to
143999999, which is mathematically correct, but when clk_round_rate() is
called with 123428571, the returned value is surprisingly 108000000.

This means that the following code works a bit oddly:

rate = clk_round_rate(clk, 123428572);
clk_set_rate(clk, rate);

As clk_set_rate() also does clock rate rounding, the result is that the
clock is set to the rate of 108000000, not 123428571 returned by the
clk_round_rate.

This patch changes the ti/clk-divider.c to use DIV_ROUND_UP when
calculating the rate. This gives the following behavior which fixes the
inconsistency:

144000000 -> 144000000
143999999 -> 123428572
123428572 -> 123428572
123428571 -> 108000000

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

CLK: ti: add support for ti divider-clock

This patch adds support for TI divider clock binding, which simply uses
the basic clock divider to provide the features needed.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>