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path: root/drivers/clk/samsung/clk.h
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2021-11-19clk: samsung: Remove meaningless __init and extern from header filesSylwester Nawrocki
Remove useless __init atrribute and unneeded extern qualifier in function declarations in header files. Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Reviewed-by: Stephen Boyd <sboyd@kernel.org> Link: https://lore.kernel.org/r/20211015151425.29743-1-s.nawrocki@samsung.com
2021-11-19clk: samsung: remove __clk_lookup() usageMarek Szyprowski
__clk_lookup() interface is obsolete, so remove it from the Samsung clock drivers. This has been achieved by getting rid of custom _get_rate() helper and replacing it with clk_hw_get_rate(). Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Acked-by: Chanwoo Choi <cw00.choi@samsung.com> Link: https://lore.kernel.org/r/20211018125456.8292-2-m.szyprowski@samsung.com Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2021-10-15clk: samsung: add support for CPU clocksWill McVicker
Adds 'struct samsung_cpu_clock' and corresponding CPU clock registration function to the samsung common clk driver. This allows samsung clock drivers to register their CPU clocks with the samsung_cmu_register_one() API. Currently the exynos5433 apollo and atlas clks have their own custom init functions to handle registering their CPU clocks. With this patch we can drop their custom CLK_OF_DECLARE functions and directly call samsung_cmu_register_one(). Signed-off-by: Will McVicker <willmcvicker@google.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Link: https://lore.kernel.org/r/20211014195347.3635601-2-willmcvicker@google.com Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner
Based on 2 normalized pattern(s): 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 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 # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-24clk: samsung: fix typoMatteo Croce
Fix spelling mistake: "lenght" -> "length" Signed-off-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2018-10-05clk: samsung: Add support for setting registers state before suspendMarek Szyprowski
Some registers of clock controller have to be set to certain values before entering system suspend state. Till now drivers did that on their own, but it will be easier to handle it by generic code and let drivers simply to provide the list of registers and their state. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Sylwester Nawrocki <snawrocki@kernel.org>
2017-10-25Merge tag 'clk-v4.15-samsung' of ↵Stephen Boyd
git://git.kernel.org/pub/scm/linux/kernel/git/snawrocki/clk into clk-next Pull Samsung clk driver updates from Sylwester Nawrocki: Overall clk/samsung clean up and fixes. Removed remaining unused code after removal of exynos4212 SoC support; dropped internal data structure fields and related code for registering clkdev lookup entry for each possible clock object, clkdev aliases could still be defined if needed in a separate table; other minor fixes of the clock tree definitions. * tag 'clk-v4.15-samsung' of git://git.kernel.org/pub/scm/linux/kernel/git/snawrocki/clk: clk: samsung: Remove obsolete clkdev alias support clk: samsung: Add explicit MPLL, EPLL clkdev aliases in S3C2443 driver clk: samsung: Rework clkdev alias handling in S3C2443 driver clk: samsung: Rework clkdev alias handling in Exynos5440 driver clk: samsung: Drop useless alias in Exynos5420 clk driver clk: samsung: Remove clkdev alias support in Exynos5250 clk driver clk: samsung: Remove double assignment of CLK_ARM_CLK in Exynos4 driver clk: samsung: Remove clkdev alias support in Exynos4 clk driver clk: samsung: Remove support for obsolete Exynos4212 CPU clock clk: samsung: Remove support for Exynos4212 SoCs in Exynos CLKOUT driver clk: samsung: Properly propagate flags in __PLL macro clk: samsung: Fix m2m scaler clock on Exynos542x clk: samsung: Delete a memory allocation error message in clk-cpu.c
2017-10-09clk: samsung: Remove obsolete clkdev alias supportMarek Szyprowski
Remove support for obsolete clkdev alias definition in generic helper macros for MUX, DIV, GATE and PLL clocks. clkdev aliases can be still created using samsung_clk_register_alias() function if given platform still needs them. All current drivers have been converted not to use *_A-style macros and checked if there are any clients for the PLL clocks, which had aliases created unconditionally. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2017-10-03clk: samsung: Properly propagate flags in __PLL macroMarek Szyprowski
All users of __PLL macro already provide flags parameter, so don't overwrite it unconditionally with CLK_GET_RATE_NOCACHE. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2017-09-07clk: samsung: exynos5433: Add support for runtime PMMarek Szyprowski
Add runtime pm support for all clock controller units (CMU), which belong to power domains and require special handling during on/off operations. Typically special values has to be written to MUX registers to change internal clocks parents to OSC clock before turning power off. During such operation all clocks, which enter CMU has to be enabled to let MUX to stabilize. Also for each CMU there is one special parent clock, which has to be enabled all the time when any access to CMU registers is being done. This patch solves most of the mysterious external abort and freeze issues caused by a lack of proper parent CMU clock enabled or incorrect turn off procedure. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com> Tested-by: Chanwoo Choi <cw00.choi@samsung.com> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Michael Turquette <mturquette@baylibre.com> Link: lkml.kernel.org/r/1503302703-13801-4-git-send-email-m.szyprowski@samsung.com
2017-09-07clk: samsung: Add support for runtime PMMarek Szyprowski
This patch adds struct device pointer to samsung_clk_provider and forwarding it to clk_register_* functions, so drivers can register clocks, which use runtime pm feature. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com> Tested-by: Chanwoo Choi <cw00.choi@samsung.com> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Michael Turquette <mturquette@baylibre.com> Link: lkml.kernel.org/r/1503302703-13801-3-git-send-email-m.szyprowski@samsung.com
2017-06-07clk: samsung: Convert common drivers to the new clk_hw APIMarek Szyprowski
Clock providers should use the new struct clk_hw based API, so convert Samsung clock providers and their helper functions to the new approach. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2016-06-02clk: samsung: exynos5433: prepare for adding CPU clocksBartlomiej Zolnierkiewicz
Open-code samsung_cmu_register_one() calls for CMU_APOLLO and CMU_ATLAS setup code as a preparation for adding CPU clocks support for Exynos5433. There should be no functional change resulting from this patch. Cc: Kukjin Kim <kgene@kernel.org> CC: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2016-06-02clk: samsung: Fully constify mux parent namesKrzysztof Kozlowski
The PNAME macro defines array of strings for names of mux parents. Although the strings itself were const but pointers to them were not thus this data resided in initdata. Make this an array of const pointers to const strings and move to initconst section. Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2016-06-02clk: samsung: Constify clock init data with clock arraysKrzysztof Kozlowski
samsung_cmu_register_one() can accept pointer to const initialization data: struct samsung_cmu_info. The members of the latter can also be pointers to const data. Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2015-07-20clk: samsung: Properly include clk.h and clkdev.hStephen Boyd
Clock provider drivers generally shouldn't include clk.h because it's the consumer API. Only include clk.h in files that are using it. The clkdev.h header isn't always used either, so remove it and add in slab.h where files were relying on it to include slab for them. Cc: Chanwoo Choi <cw00.choi@samsung.com> Cc: Sylwester Nawrocki <s.nawrocki@samsung.com> Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com> Cc: Kukjin Kim <kgene.kim@samsung.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-06-04clk: make several parent names constUwe Kleine-König
Since commit 2893c379461a ("clk: make strings in parent name arrays const") the name of parent clocks can be const. So add more const in several clock drivers. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2014-12-23clk: samsung: Change the return value of samsung_cmu_register_one()Chanwoo Choi
This patch changes the return value of samsung_cmu_register_one() from 'void' to 'samsung_clk_provider structure' pointer type because samsung_clk_provider may be used in each clock driver. Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2014-12-02clk: samsung: remove unnecessary inclusion of header files from clk.hPankaj Dubey
Let's remove unnecessary include of header files from clk.h and add required one in clk.c Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com> [s.nawrocki@samsung.com: dropped removal of '#include <linux/syscore_ops.h>'] Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2014-12-02clk: samsung: Spelling s/bwtween/between/Pankaj Dubey
Fix a typo in comment section of "struct samsung_clk_provider". Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2014-10-31clk: samsung: Add fixed_factor_clocks field to struct exynos_cmu_infoNaveen Krishna Ch
Add the fields "fixed_factor_clks" and "nr_fixed_factor_clks" to "struct exynos_cmu_info" to allow registering of fixed factor clocks as well with exynos_cmu_register_one(). Signed-off-by: Naveen Krishna Ch <naveenkrishna.ch@gmail.com> Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com> Reviewed-by: Thomas Abraham <thomas.ab@samsung.com> Tested-by: Thomas Abraham <thomas.ab@samsung.com> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2014-10-31clk: samsung: Factor out the common code to clk.cNaveen Krishna Ch
While adding clock support for Exynos5260, the infrastructure to register multiple clock controllers was introduced. Factor out the support for registering multiple clock controller from Exynos5260 clock code to common samsung clock code so that it can be used by other Exynos SoC which have multiple clock controllers. Signed-off-by: Naveen Krishna Ch <naveenkrishna.ch@gmail.com> Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com> Reviewed-by: Thomas Abraham <thomas.ab@samsung.com> Tested-by: Thomas Abraham <thomas.ab@samsung.com> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2014-07-26clk: samsung: Make of_device_id array constKrzysztof Kozlowski
Array of struct of_device_id may be be const as expected by of_match_table field and of_find_matching_node_and_match() function. Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Reviewed-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Tomasz Figa <t.figa@samsung.com>
2014-06-30clk: samsung: Register clk provider only after registering its all clocksSylwester Nawrocki
Ensure the clock provider is not registered until after all its related clocks were created and are ready to use. Currently there are races possible and any (of_)clk_get() call right after a clock provider's clk_init_cb callback call may fail. Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Tomasz Figa <t.figa@samsung.com>
2014-05-14clk/samsung: add support for multiple clock providersRahul Sharma
Samsung CCF helper functions do not provide support to register multiple Clock Providers for a given SoC. Due to this limitation, SoC platforms are not able to use these helpers for registering multiple clock providers and are forced to bypass this layer. This layer is modified accordingly to enable the support for multiple clock providers. Clock file for exynos4, exynos5250, exynos5420, exynos5440, S3c64xx, S3c24xx are also modified as per changed helper functions. Signed-off-by: Rahul Sharma <rahul.sharma@samsung.com> [t.figa: Modified s3c2410 clock driver as well] Signed-off-by: Tomasz Figa <t.figa@samsung.com>
2014-02-14clk: samsung: Drop old suspend/resume codeTomasz Figa
Since all SoC drivers have been moved to local suspend/resume handling, the old code can be safely dropped. Signed-off-by: Tomasz Figa <t.figa@samsung.com> Acked-by: Kyungmin Park <kyungmin.park@samsung.com> Acked-by: Heiko Stuebner <heiko@sntech.de> Reviewed-by: Thomas Abraham <thomas.ab@samsung.com> Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2014-02-14clk: samsung: exynos5250: Move suspend/resume handling to SoC driverTomasz Figa
Since there are multiple differences in how suspend/resume of particular Exynos SoCs must be handled, SoC driver is better place for suspend/resume handlers and so this patch moves them. Signed-off-by: Tomasz Figa <t.figa@samsung.com> Acked-by: Kyungmin Park <kyungmin.park@samsung.com> Reviewed-by: Thomas Abraham <thomas.ab@samsung.com> Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2014-02-14clk: samsung: Provide common helpers for register save/restoreTomasz Figa
As suspend/resume handlers are being moved to SoC specific code, due to differencies in suspend/resume handling of particular SoCs, to minimize code duplication this patch provides common register save/restore helpers that save/restore given list of registers of clock controller. Signed-off-by: Tomasz Figa <t.figa@samsung.com> Acked-by: Kyungmin Park <kyungmin.park@samsung.com> Acked-by: Heiko Stuebner <heiko@sntech.de> Reviewed-by: Thomas Abraham <thomas.ab@samsung.com> Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2013-08-19clk: add CLK_SET_RATE_NO_REPARENT flagJames Hogan
Add a CLK_SET_RATE_NO_REPARENT clock flag, which will prevent muxes being reparented during clk_set_rate. To avoid breaking existing platforms, all callers of clk_register_mux() are adjusted to pass the new flag. Platform maintainers are encouraged to remove the flag if they wish to allow mux reparenting on set_rate. Signed-off-by: James Hogan <james.hogan@imgtec.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Mike Turquette <mturquette@linaro.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Sascha Hauer <kernel@pengutronix.de> Cc: Stephen Warren <swarren@wwwdotorg.org> Cc: Viresh Kumar <viresh.linux@gmail.com> Cc: Kukjin Kim <kgene.kim@samsung.com> Cc: Haojian Zhuang <haojian.zhuang@linaro.org> Cc: Chao Xie <xiechao.mail@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: "Emilio López" <emilio@elopez.com.ar> Cc: Gregory CLEMENT <gregory.clement@free-electrons.com> Cc: Maxime Ripard <maxime.ripard@free-electrons.com> Cc: Prashant Gaikwad <pgaikwad@nvidia.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Peter De Schrijver <pdeschrijver@nvidia.com> Cc: Pawel Moll <pawel.moll@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrew Chew <achew@nvidia.com> Cc: Doug Anderson <dianders@chromium.org> Cc: Heiko Stuebner <heiko@sntech.de> Cc: Paul Walmsley <pwalmsley@nvidia.com> Cc: Sylwester Nawrocki <s.nawrocki@samsung.com> Cc: Thomas Abraham <thomas.abraham@linaro.org> Cc: Tomasz Figa <t.figa@samsung.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: spear-devel@list.st.com Cc: linux-tegra@vger.kernel.org Tested-by: Haojian Zhuang <haojian.zhuang@gmail.com> Acked-by: Stephen Warren <swarren@nvidia.com> [tegra] Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> [sunxi] Acked-by: Sören Brinkmann <soren.brinkmann@xilinx.com> [Zynq] Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-08-02clk: samsung: Add EPLL and VPLL freq table for exynos5250 SoCVikas Sajjan
Adds the EPLL and VPLL freq table for exynos5250 SoC. Signed-off-by: Vikas Sajjan <vikas.sajjan@linaro.org> Signed-off-by: Yadwinder Singh Brar <yadi.brar@samsung.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-08-02clk: samsung: Add support to register rate_table for samsung pllsYadwinder Singh Brar
This patch defines a common rate_table which will contain recommended p, m, s, k values for supported rates that needs to be changed for changing corresponding PLL's rate. Reviewed-by: Doug Anderson <dianders@chromium.org> Signed-off-by: Yadwinder Singh Brar <yadi.brar@samsung.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-08-02clk: samsung: Define a common samsung_clk_register_pll()Yadwinder Singh Brar
This patch defines a common samsung_clk_register_pll() Since pll2550 & pll35xx and pll2650 & pll36xx have exactly same clk ops implementation, added pll2550 and pll2650 also. Signed-off-by: Yadwinder Singh Brar <yadi.brar@samsung.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-06-22clk: samsung: Add MUX_FA macro to pass flag and aliasTushar Behera
Cpufreq driver for some Samsung platforms have not yet been designed as a platform driver, thereby they can only access clocks with an alias name. For EXYNOS4210, one such clock also requires a flag to be set, hence there is a need to create another macro that can handle both flag and alias. Signed-off-by: Tushar Behera <tushar.behera@linaro.org> Reviewed-by: Tomasz Figa <t.figa@samsung.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-04-19clk: exynos: prepare for multiplatformArnd Bergmann
The new common clock drivers for exynos are using compile time constants and soc_is_exynos* macros to provide backwards compatibility for pre-DT systems, which is not possible with multiplatform kernels. This moves all the necessary information back into platform code and removes the mach/* header inclusions. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Mike Turquette <mturquette@linaro.org>
2013-04-04clk: exynos4: Add support for SoC-specific register save listTomasz Figa
This patch extends suspend/resume support for SoC-specific registers to handle differences in register sets on particular SoCs. Signed-off-by: Tomasz Figa <t.figa@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Reviewed-by: Thomas Abraham <thomas.abraham@linaro.org> Acked-by: Mike Turquette <mturquette@linaro.org> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2013-03-28clk: samsung: add infrastructure to add separate aliasesHeiko Stuebner
The current code adds aliases, if necessary, directly when adding the clock, limiting the number of possible aliases to one. Some platforms need more than one alias, like the hsmmc pclocks on s3c2416 which need a "hsmmc" and "mmc_busclk.0" alias for the s3c- sdhci driver. Therefore add the possibility to separately add clock aliases for previously created clocks. Signed-off-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Mike Turquette <mturquette@linaro.org> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2013-03-28clk: samsung: register clk_div_tables for divider clocksHeiko Stuebner
On some Samsung platforms divider clocks only use specific divider combinations like the armdiv on s3c2443 and s3c2416. For these usecases the generic divider clock already provides the option of providing a lookup table mapping register values to divider values. Therefore add a new field to samsung_div_clock and if filled with a table, use clk_register_divider_table instead of clk_register_divider to register a divider clock Signed-off-by: Heiko Stuebner <heiko@sntech.de> Reviewed-by: Thomas Abraham <thomas.abraham@linaro.org> Acked-by: Mike Turquette <mturquette@linaro.org> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2013-03-25clk: samsung: add common clock framework helper functions for Samsung platformsThomas Abraham
All Samsung platforms include different types of clock including fixed-rate, mux, divider and gate clock types. There are typically hundreds of such clocks on each of the Samsung platforms. To enable Samsung platforms to register these clocks using the common clock framework, a bunch of utility functions are introduced here which simplify the clock registration process. The clocks are usually statically instantiated and registered with common clock framework. Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Tested-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Reviewed-by: Tomasz Figa <t.figa@samsung.com> Tested-by: Tomasz Figa <t.figa@samsung.com> Tested-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org> Acked-by: Mike Turquette <mturquette@linaro.org> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>