clk: composite: Fix handling of high clock rates

ULONG_MAX is used by a few drivers to figure out the highest available
clock rate via clk_round_rate(clk, ULONG_MAX). Since abs() takes a
signed valu

clk: composite: Fix handling of high clock rates

ULONG_MAX is used by a few drivers to figure out the highest available
clock rate via clk_round_rate(clk, ULONG_MAX). Since abs() takes a
signed value as input, the current logic effectively calculates with
ULONG_MAX = -1, which results in the worst parent clock being chosen
instead of the best one.

For example on Rockchip RK3588 the eMMC driver tries to figure out
the highest available clock rate. There are three parent clocks
available resulting in the following rate diffs with the existing
logic:

GPLL: abs(18446744073709551615 - 1188000000) = 1188000001
CPLL: abs(18446744073709551615 - 1500000000) = 1500000001
XIN24M: abs(18446744073709551615 - 24000000) = 24000001

As a result the clock framework will promote a maximum supported
clock rate of 24 MHz, even though 1.5GHz are possible. With the
updated logic any casting between signed and unsigned is avoided
and the numbers look like this instead:

GPLL: 18446744073709551615 - 1188000000 = 18446744072521551615
CPLL: 18446744073709551615 - 1500000000 = 18446744072209551615
XIN24M: 18446744073709551615 - 24000000 = 18446744073685551615

As a result the parent with the highest acceptable rate is chosen
instead of the parent clock with the lowest one.

Cc: stable@vger.kernel.org
Fixes: 49502408007b ("mmc: sdhci-of-dwcmshc: properly determine max clock on Rockchip")
Tested-by: Christopher Obbard <chris.obbard@collabora.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://lore.kernel.org/r/20230526171057.66876-2-sebastian.reichel@collabora.com
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

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clk: Stop forwarding clk_rate_requests to the parent

If the clock cannot modify its rate and has CLK_SET_RATE_PARENT,
clk_mux_determine_rate_flags(), clk_core_round_rate_nolock() and a
number of dri

clk: Stop forwarding clk_rate_requests to the parent

If the clock cannot modify its rate and has CLK_SET_RATE_PARENT,
clk_mux_determine_rate_flags(), clk_core_round_rate_nolock() and a
number of drivers will forward the clk_rate_request to the parent clock.

clk_core_round_rate_nolock() will pass the pointer directly, which means
that we pass a clk_rate_request to the parent that has the rate,
min_rate and max_rate of the child, and the best_parent_rate and
best_parent_hw fields will be relative to the child as well, so will
point to our current clock and its rate. The most common case for
CLK_SET_RATE_PARENT is that the child and parent clock rates will be
equal, so the rate field isn't a worry, but the other fields are.

Similarly, if the parent clock driver ever modifies the best_parent_rate
or best_parent_hw, this will be applied to the child once the call to
clk_core_round_rate_nolock() is done. best_parent_hw is probably not
going to be a valid parent, and best_parent_rate might lead to a parent
rate change different to the one that was initially computed.

clk_mux_determine_rate_flags() and the affected drivers will copy the
request before forwarding it to the parents, so they won't be affected
by the latter issue, but the former is still going to be there and will
lead to erroneous data and context being passed to the various clock
drivers in the same sub-tree.

Let's create two new functions, clk_core_forward_rate_req() and
clk_hw_forward_rate_request() for the framework and the clock providers
that will copy a request from a child clock and update the context to
match the parent's. We also update the relevant call sites in the
framework and drivers to use that new function.

Let's also add a test to make sure we avoid regressions there.

Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> # imx8mp
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> # exynos4210, meson g12b
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220816112530.1837489-22-maxime@cerno.tech
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

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clk: composite: Fix 'switching' to same clock

During commit 6594988fd625 ("clk: composite: Use rate_ops.determine_rate
when also a mux is available") setting req->best_parent_hw got lost,
so best_pa

clk: composite: Fix 'switching' to same clock

During commit 6594988fd625 ("clk: composite: Use rate_ops.determine_rate
when also a mux is available") setting req->best_parent_hw got lost,
so best_parent_hw stays NULL during switch to the same parent. This
results in the (debug) message:
clk_calc_new_rates: lcdif_pixel not gated but wants to reparent
and the following rate change is dropped.

Fixes: 6594988fd625 ("clk: composite: Use rate_ops.determine_rate when also a mux is available")
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Link: https://lore.kernel.org/r/20211103122441.3208576-1-alexander.stein@ew.tq-group.com
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

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clk: composite: Use rate_ops.determine_rate when also a mux is available

Update clk_composite_determine_rate() to use rate_ops.determine_rate
when available in combination with a mux. So far clk_div

clk: composite: Use rate_ops.determine_rate when also a mux is available

Update clk_composite_determine_rate() to use rate_ops.determine_rate
when available in combination with a mux. So far clk_divider_ops provide
both, .round_rate and .determine_rate. Removing the former would make
clk-composite fail silently for example on Rockchip platforms (which
heavily use composite clocks).
Add support for using rate_ops.determine_rate when either
rate_ops.round_rate is not available or both (.round_rate and
.determine_rate) are provided.

Suggested-by: Alex Bee <knaerzche@gmail.com>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/20211016105022.303413-3-martin.blumenstingl@googlemail.com
Tested-by: Alex Bee <knaerzche@gmail.com>
Tested-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

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clk: composite: export clk_register_composite

To support module build of mediatek clk drivers,
it is necessary to export clk_register_composite.

Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Hanks Chen <

clk: composite: export clk_register_composite

To support module build of mediatek clk drivers,
it is necessary to export clk_register_composite.

Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Hanks Chen <hanks.chen@mediatek.com>
Cc: Wendell Lin <wendell.lin@mediatek.com>
Cc: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Link: https://lore.kernel.org/r/20210901222526.31065-2-miles.chen@mediatek.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

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clk: composite: Also consider .determine_rate for rate + mux composites

Commit 69a00fb3d69706 ("clk: divider: Implement and wire up
.determine_rate by default") switches clk_divider_ops to implement

clk: composite: Also consider .determine_rate for rate + mux composites

Commit 69a00fb3d69706 ("clk: divider: Implement and wire up
.determine_rate by default") switches clk_divider_ops to implement
.determine_rate by default. This breaks composite clocks with multiple
parents because clk-composite.c does not use the special handling for
mux + divider combinations anymore (that was restricted to rate clocks
which only implement .round_rate, but not .determine_rate).

Alex reports:
This breaks lot of clocks for Rockchip which intensively uses
composites, i.e. those clocks will always stay at the initial parent,
which in some cases is the XTAL clock and I strongly guess it is the
same for other platforms, which use composite clocks having more than
one parent (e.g. mediatek, ti ...)

Example (RK3399)
clk_sdio is set (initialized) with XTAL (24 MHz) as parent in u-boot.
It will always stay at this parent, even if the mmc driver sets a rate
of 200 MHz (fails, as the nature of things), which should switch it
to any of its possible parent PLLs defined in
mux_pll_src_cpll_gpll_npll_ppll_upll_24m_p (see clk-rk3399.c) - which
never happens.

Restore the original behavior by changing the priority of the conditions
inside clk-composite.c. Now the special rate + mux case (with rate_ops
having a .round_rate - which is still the case for the default
clk_divider_ops) is preferred over rate_ops which have .determine_rate
defined (and not further considering the mux).

Fixes: 69a00fb3d69706 ("clk: divider: Implement and wire up .determine_rate by default")
Reported-by: Alex Bee <knaerzche@gmail.com>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/20211016105022.303413-2-martin.blumenstingl@googlemail.com
Tested-by: Alex Bee <knaerzche@gmail.com>
Tested-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

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clk: composite: add devm_clk_hw_register_composite_pdata()

This will simplify drivers which would only unregister the clk in their
remove() op.

Signed-off-by: Michael Walle <michael@walle.cc>
Link:

clk: composite: add devm_clk_hw_register_composite_pdata()

This will simplify drivers which would only unregister the clk in their
remove() op.

Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20201105192746.19564-3-michael@walle.cc
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

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clk: composite: Export clk_hw_register_composite()

Export clk_hw_register_composite() to support user built as module.

ERROR: modpost: "clk_hw_register_composite" [drivers/clk/imx/mxc-clk.ko]
undef

clk: composite: Export clk_hw_register_composite()

Export clk_hw_register_composite() to support user built as module.

ERROR: modpost: "clk_hw_register_composite" [drivers/clk/imx/mxc-clk.ko]
undefined!

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

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clk: composite: add _register_composite_pdata() variants

Add support for the new way of specifying the clock parents. Add the
two new functions
clk_hw_register_composite_pdata()
clk_register

clk: composite: add _register_composite_pdata() variants

Add support for the new way of specifying the clock parents. Add the
two new functions
clk_hw_register_composite_pdata()
clk_register_composite_pdata()
to let the driver provide parent_data instead of the parent_names.

Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lkml.kernel.org/r/20200102231101.11834-1-michael@walle.cc
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

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clk: Add clk_hw_unregister_composite helper function definition

This function has been delcared but not defined anywhere. Hence, this
commit adds definition for it.

Fixes: 49cb392d3639 ("clk: compo

clk: Add clk_hw_unregister_composite helper function definition

This function has been delcared but not defined anywhere. Hence, this
commit adds definition for it.

Fixes: 49cb392d3639 ("clk: composite: Add hw based registration APIs")
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lkml.kernel.org/r/20191115162901.17456-3-manivannan.sadhasivam@linaro.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

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clk: Zero init clk_init_data in helpers

The clk_init_data struct needs to be initialized to zero for the new
parent_map implementation to work correctly. Otherwise, the member which
is available fir

clk: Zero init clk_init_data in helpers

The clk_init_data struct needs to be initialized to zero for the new
parent_map implementation to work correctly. Otherwise, the member which
is available first will get processed.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lkml.kernel.org/r/20191115162901.17456-2-manivannan.sadhasivam@linaro.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

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clk: composite: Drop unused clk.h include

This include isn't used. Drop it.

Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lkml.kernel.org/r/20190815042500.9519-1-sboyd@kernel.org

clk: Remove CLK_IS_BASIC clk flag

This flag was historically used to indicate that a clk is a "basic" type
of clk like a mux, divider, gate, etc. This never turned out to be very
useful though becau

clk: Remove CLK_IS_BASIC clk flag

This flag was historically used to indicate that a clk is a "basic" type
of clk like a mux, divider, gate, etc. This never turned out to be very
useful though because it was hard to cleanly split "basic" clks from
other clks in a system. This one flag was a way for type introspection
and it just didn't scale. If anything, it was used by the TI clk driver
to indicate that a clk_hw wasn't contained in the SoC specific clk
structure. We can get rid of this define now that TI is finding those
clks a different way.

Cc: Tero Kristo <t-kristo@ti.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: <linux-mips@vger.kernel.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: <linux-pwm@vger.kernel.org>
Cc: <linux-amlogic@lists.infradead.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

show more ...

clk: Tag basic clk types with SPDX

These are all GPL-2.0 files per the existing license text. Replace the
boiler plate with the tag.

Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: composite: Add unregister function

The composite clock didn't have any unregistration function, which forced
us to use clk_unregister directly on it.

While it was already not great from an API

clk: composite: Add unregister function

The composite clock didn't have any unregistration function, which forced
us to use clk_unregister directly on it.

While it was already not great from an API point of view, it also meant
that we were leaking the clk_composite structure allocated in
clk_register_composite.

Add a clk_unregister_composite function to fix this.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

show more ...

clk: composite: Add hw based registration APIs

Add registration APIs in the clk composite code to return struct
clk_hw pointers instead of struct clk pointers. This way we hide
the struct clk pointe

clk: composite: Add hw based registration APIs

Add registration APIs in the clk composite code to return struct
clk_hw pointers instead of struct clk pointers. This way we hide
the struct clk pointer from providers unless they need to use
consumer facing APIs.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

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clk: Add clk_composite_set_rate_and_parent

When changing the clock-rate, currently a new parent is set first and a
divider adapted thereafter. This may result in the clock-rate overflowing
its targe

clk: Add clk_composite_set_rate_and_parent

When changing the clock-rate, currently a new parent is set first and a
divider adapted thereafter. This may result in the clock-rate overflowing
its target rate for a short time if the new parent has a higher rate than
the old parent.

While this often doesn't produce negative effects, it can affect components
in a voltage-scaling environment, like the GPU on the rk3399 socs, where
the voltage than simply is to low for the temporarily to high clock rate.

For general clock hirarchies this may need more extensive adaptions to
the common clock-framework, but at least for composite clocks having
both parent and rate settings it is easy to create a short-term solution to
make sure the clock-rate does not overflow the target.

Signed-off-by: Finley Xiao <finley.xiao@rock-chips.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

show more ...

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

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>

show more ...

clk: Convert basic types 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.

Signed-off-by: Stephen Boyd

clk: Convert basic types 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.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

show more ...

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-kr

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>

show more ...

clk: Replace __clk_get_num_parents with clk_hw_get_num_parents()

Mostly converted with the following semantic patch:

@@
struct clk_hw *E;
@@

-__clk_get_num_parents(E->clk)
+clk_hw_get_num_parents(

clk: Replace __clk_get_num_parents with clk_hw_get_num_parents()

Mostly converted with the following semantic patch:

@@
struct clk_hw *E;
@@

-__clk_get_num_parents(E->clk)
+clk_hw_get_num_parents(E)

Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Chao Xie <chao.xie@marvell.com>
Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Cc: Tomasz Figa <tomasz.figa@gmail.com>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: "Emilio López" <emilio@elopez.com.ar>
Acked-by: Tero Kristo <t-kristo@ti.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

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clk: fix some determine_rate implementations

Some determine_rate implementations are not returning an error
when they failed to adapt the rate according to the rate request.
Fix them so that they re

clk: fix some determine_rate implementations

Some determine_rate implementations are not returning an error
when they failed to adapt the rate according to the rate request.
Fix them so that they return an error instead of silently
returning 0.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
CC: Jonathan Corbet <corbet@lwn.net>
CC: Tony Lindgren <tony@atomide.com>
CC: Ralf Baechle <ralf@linux-mips.org>
CC: "Emilio López" <emilio@elopez.com.ar>
CC: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Tero Kristo <t-kristo@ti.com>
CC: Peter De Schrijver <pdeschrijver@nvidia.com>
CC: Prashant Gaikwad <pgaikwad@nvidia.com>
CC: Stephen Warren <swarren@wwwdotorg.org>
CC: Thierry Reding <thierry.reding@gmail.com>
CC: Alexandre Courbot <gnurou@gmail.com>
CC: linux-doc@vger.kernel.org
CC: linux-kernel@vger.kernel.org
CC: linux-arm-kernel@lists.infradead.org
CC: linux-omap@vger.kernel.org
CC: linux-mips@linux-mips.org
CC: linux-tegra@vger.kernel.org
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

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clk: change clk_ops' ->determine_rate() prototype

Clock rates are stored in an unsigned long field, but ->determine_rate()
(which returns a rounded rate from a requested one) returns a long
value (e

clk: change clk_ops' ->determine_rate() prototype

Clock rates are stored in an unsigned long field, but ->determine_rate()
(which returns a rounded rate from a requested one) returns a long
value (errors are reported using negative error codes), which can lead
to long overflow if the clock rate exceed 2Ghz.

Change ->determine_rate() prototype to return 0 or an error code, and pass
a pointer to a clk_rate_request structure containing the expected target
rate and the rate constraints imposed by clk users.

The clk_rate_request structure might be extended in the future to contain
other kind of constraints like the rounding policy, the maximum clock
inaccuracy or other things that are not yet supported by the CCF
(power consumption constraints ?).

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
CC: Jonathan Corbet <corbet@lwn.net>
CC: Tony Lindgren <tony@atomide.com>
CC: Ralf Baechle <ralf@linux-mips.org>
CC: "Emilio López" <emilio@elopez.com.ar>
CC: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Tero Kristo <t-kristo@ti.com>
CC: Peter De Schrijver <pdeschrijver@nvidia.com>
CC: Prashant Gaikwad <pgaikwad@nvidia.com>
CC: Stephen Warren <swarren@wwwdotorg.org>
CC: Thierry Reding <thierry.reding@gmail.com>
CC: Alexandre Courbot <gnurou@gmail.com>
CC: linux-doc@vger.kernel.org
CC: linux-kernel@vger.kernel.org
CC: linux-arm-kernel@lists.infradead.org
CC: linux-omap@vger.kernel.org
CC: linux-mips@linux-mips.org
CC: linux-tegra@vger.kernel.org
[sboyd@codeaurora.org: Fix parent dereference problem in
__clk_determine_rate()]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Romain Perier <romain.perier@gmail.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
[sboyd@codeaurora.org: Folded in fix from Heiko for fixed-rate
clocks without parents or a rate determining op]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

show more ...

clk: basic-types: Remove useless allocation failure printks

Printing an error on kmalloc() failures is unnecessary. Remove
the print and use *ptr in sizeof() for future-proof code.

Signed-off-by: S

clk: basic-types: Remove useless allocation failure printks

Printing an error on kmalloc() failures is unnecessary. Remove
the print and use *ptr in sizeof() for future-proof code.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

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clk: make strings in parent name arrays const

The clk functions and structs declare the parent_name arrays as
'const char **parent_names' which means the parent name strings
are const, but the array

clk: make strings in parent name arrays const

The clk functions and structs declare the parent_name arrays as
'const char **parent_names' which means the parent name strings
are const, but the array itself is not. Use
'const char * const * parent_names' instead which also makes
the array const. This allows us to put the parent_name arrays into
the __initconst section.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
[sboyd@codeaurora.org: Squelch 80-character checkpatch warnings]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

show more ...