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2021-09-22clk: fix build warning for orphan_listGreg Kroah-Hartman1-5/+5
In the backport of commit bdcf1dc25324 ("clk: Evict unregistered clks from parent caches") to the 4.19.y and 4.14.y stable trees, the orphan_list structure was placed in the wrong location, causing loads of build warnings on systems that do not define CONFIG_DEBUG_FS. Fix this up by moving the structure to the correct place in the file. Reported-by: "kernelci.org bot" <bot@kernelci.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-16clk: fix invalid usage of list cursor in unregisterLukasz Bartosik1-17/+13
[ Upstream commit 7045465500e465b09f09d6e5bdc260a9f1aab97b ] Fix invalid usage of a list_for_each_entry cursor in clk_notifier_unregister(). When list is empty or if the list is completely traversed (without breaking from the loop on one of the entries) then the list cursor does not point to a valid entry and therefore should not be used. The patch fixes a logical bug that hasn't been seen in pratice however it is analogus to the bug fixed in clk_notifier_register(). The issue was dicovered when running 5.12-rc1 kernel on x86_64 with KASAN enabled: BUG: KASAN: global-out-of-bounds in clk_notifier_register+0xab/0x230 Read of size 8 at addr ffffffffa0d10588 by task swapper/0/1 CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.12.0-rc1 #1 Hardware name: Google Caroline/Caroline, BIOS Google_Caroline.7820.430.0 07/20/2018 Call Trace: dump_stack+0xee/0x15c print_address_description+0x1e/0x2dc kasan_report+0x188/0x1ce ? clk_notifier_register+0xab/0x230 ? clk_prepare_lock+0x15/0x7b ? clk_notifier_register+0xab/0x230 clk_notifier_register+0xab/0x230 dw8250_probe+0xc01/0x10d4 ... Memory state around the buggy address: ffffffffa0d10480: 00 00 00 00 00 03 f9 f9 f9 f9 f9 f9 00 00 00 00 ffffffffa0d10500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f9 f9 >ffffffffa0d10580: f9 f9 f9 f9 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffffffffa0d10600: 00 00 00 00 00 00 f9 f9 f9 f9 f9 f9 00 00 00 00 ffffffffa0d10680: 00 00 00 00 00 00 00 00 f9 f9 f9 f9 00 00 00 00 ================================================================== Fixes: b2476490ef11 ("clk: introduce the common clock framework") Reported-by: Lukasz Majczak <lma@semihalf.com> Signed-off-by: Lukasz Bartosik <lb@semihalf.com> Link: https://lore.kernel.org/r/20210401225149.18826-2-lb@semihalf.com Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-16clk: fix invalid usage of list cursor in registerLukasz Bartosik1-9/+8
[ Upstream commit 8d3c0c01cb2e36b2bf3c06a82b18b228d0c8f5d0 ] Fix invalid usage of a list_for_each_entry cursor in clk_notifier_register(). When list is empty or if the list is completely traversed (without breaking from the loop on one of the entries) then the list cursor does not point to a valid entry and therefore should not be used. The issue was dicovered when running 5.12-rc1 kernel on x86_64 with KASAN enabled: BUG: KASAN: global-out-of-bounds in clk_notifier_register+0xab/0x230 Read of size 8 at addr ffffffffa0d10588 by task swapper/0/1 CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.12.0-rc1 #1 Hardware name: Google Caroline/Caroline, BIOS Google_Caroline.7820.430.0 07/20/2018 Call Trace: dump_stack+0xee/0x15c print_address_description+0x1e/0x2dc kasan_report+0x188/0x1ce ? clk_notifier_register+0xab/0x230 ? clk_prepare_lock+0x15/0x7b ? clk_notifier_register+0xab/0x230 clk_notifier_register+0xab/0x230 dw8250_probe+0xc01/0x10d4 ... Memory state around the buggy address: ffffffffa0d10480: 00 00 00 00 00 03 f9 f9 f9 f9 f9 f9 00 00 00 00 ffffffffa0d10500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f9 f9 >ffffffffa0d10580: f9 f9 f9 f9 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffffffffa0d10600: 00 00 00 00 00 00 f9 f9 f9 f9 f9 f9 00 00 00 00 ffffffffa0d10680: 00 00 00 00 00 00 00 00 f9 f9 f9 f9 00 00 00 00 ================================================================== Fixes: b2476490ef11 ("clk: introduce the common clock framework") Reported-by: Lukasz Majczak <lma@semihalf.com> Signed-off-by: Lukasz Bartosik <lb@semihalf.com> Link: https://lore.kernel.org/r/20210401225149.18826-1-lb@semihalf.com Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26clk: Evict unregistered clks from parent cachesStephen Boyd1-11/+41
commit bdcf1dc253248542537a742ae1e7ccafdd03f2d3 upstream. We leave a dangling pointer in each clk_core::parents array that has an unregistered clk as a potential parent when that clk_core pointer is freed by clk{_hw}_unregister(). It is impossible for the true parent of a clk to be set with clk_set_parent() once the dangling pointer is left in the cache because we compare parent pointers in clk_fetch_parent_index() instead of checking for a matching clk name or clk_hw pointer. Before commit ede77858473a ("clk: Remove global clk traversal on fetch parent index"), we would check clk_hw pointers, which has a higher chance of being the same between registration and unregistration, but it can still be allocated and freed by the clk provider. In fact, this has been a long standing problem since commit da0f0b2c3ad2 ("clk: Correct lookup logic in clk_fetch_parent_index()") where we stopped trying to compare clk names and skipped over entries in the cache that weren't NULL. There are good (performance) reasons to not do the global tree lookup in cases where the cache holds dangling pointers to parents that have been unregistered. Let's take the performance hit on the uncommon registration path instead. Loop through all the clk_core::parents arrays when a clk is unregistered and set the entry to NULL when the parent cache entry and clk being unregistered are the same pointer. This will fix this problem and avoid the overhead for the "normal" case. Based on a patch by Bjorn Andersson. Fixes: da0f0b2c3ad2 ("clk: Correct lookup logic in clk_fetch_parent_index()") Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Link: https://lkml.kernel.org/r/20190828181959.204401-1-sboyd@kernel.org Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-24clk: Fix debugfs_create_*() usageGeert Uytterhoeven1-17/+15
commit 4c8326d5ebb0de3191e98980c80ab644026728d0 upstream. When exposing data access through debugfs, the correct debugfs_create_*() functions must be used, matching the data types. Remove all casts from data pointers passed to debugfs_create_*() functions, as such casts prevent the compiler from flagging bugs. clk_core.rate and .accuracy are "unsigned long", hence casting their addresses to "u32 *" exposed the wrong halves on big-endian 64-bit systems. Fix this by using debugfs_create_ulong() instead. Octal permissions are preferred, as they are easier to read than symbolic permissions. Hence replace "S_IRUGO" by "0444" throughout. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> [sboyd@codeaurora.org: Squash the octal change in too] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-23clk: Don't try to enable critical clocks if prepare failedGuenter Roeck1-2/+8
commit 12ead77432f2ce32dea797742316d15c5800cb32 upstream. The following traceback is seen if a critical clock fails to prepare. bcm2835-clk 3f101000.cprman: plld: couldn't lock PLL ------------[ cut here ]------------ Enabling unprepared plld_per WARNING: CPU: 1 PID: 1 at drivers/clk/clk.c:1014 clk_core_enable+0xcc/0x2c0 ... Call trace: clk_core_enable+0xcc/0x2c0 __clk_register+0x5c4/0x788 devm_clk_hw_register+0x4c/0xb0 bcm2835_register_pll_divider+0xc0/0x150 bcm2835_clk_probe+0x134/0x1e8 platform_drv_probe+0x50/0xa0 really_probe+0xd4/0x308 driver_probe_device+0x54/0xe8 device_driver_attach+0x6c/0x78 __driver_attach+0x54/0xd8 ... Check return values from clk_core_prepare() and clk_core_enable() and bail out if any of those functions returns an error. Cc: Jerome Brunet <jbrunet@baylibre.com> Fixes: 99652a469df1 ("clk: migrate the count of orphaned clocks at init") Signed-off-by: Guenter Roeck <linux@roeck-us.net> Link: https://lkml.kernel.org/r/20191225163429.29694-1-linux@roeck-us.net Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-26clk: core: Potentially free connection idMikko Perttunen1-0/+3
[ Upstream commit 365f7a89c881e84f1ebc925f65f899d5d7ce547e ] Patch "clk: core: Copy connection id" made it so that the connector id 'con_id' is kstrdup_const()ed to cater to drivers that pass non-constant connection ids. The patch added the corresponding kfree_const to __clk_free_clk(), but struct clk's can be freed also via __clk_put(). Add the kfree_const call to __clk_put() and add comments to both functions to remind that the logic in them should be kept in sync. Fixes: 253160a8ad06 ("clk: core: Copy connection id") Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com> Reviewed-by: Leonard Crestez <leonard.crestez@nxp.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-20clk: honor CLK_MUX_ROUND_CLOSEST in generic clk muxJerome Brunet1-3/+4
[ Upstream commit 4ad69b80e886a845f56ce0a3d10211208693d92b ] CLK_MUX_ROUND_CLOSEST is part of the clk_mux documentation but clk_mux directly calls __clk_mux_determine_rate(), which overrides the flag. As result, if clk_mux is instantiated with CLK_MUX_ROUND_CLOSEST, the flag will be ignored and the clock rounded down. To solve this, this patch expose clk_mux_determine_rate_flags() in the clk-provider API and uses it in the determine_rate() callback of clk_mux. Fixes: 15a02c1f6dd7 ("clk: Add __clk_mux_determine_rate_closest") Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25clk: Don't show the incorrect clock phaseShawn Lin1-0/+3
[ Upstream commit 1f9c63e8de3d7b377c9d74e4a17524cfb60e6384 ] It's found that the clock phase output from clk_summary is wrong compared to the actual phase reading from the register. cat /sys/kernel/debug/clk/clk_summary | grep sdio_sample sdio_sample 0 1 0 50000000 0 -22 It exposes an issue that clk core, clk_core_get_phase, always returns the cached core->phase which should be either updated by calling clk_set_phase or directly from the first place the clk was registered. When registering the clk, the core->phase geting from ->get_phase() may return negative value indicating error. This is quite common since the clk's phase may be highly related to its parent chain, but it was temporarily orphan when registered, since its parent chains hadn't be ready at that time, so the clk drivers decide to return error in this case. However, if no clk_set_phase is called or maybe the ->set_phase() isn't even implemented, the core->phase would never be updated. This is wrong, and we should try to update it when all its parent chains are settled down, like the way of updating clock rate for that. But it's not deserved to complicate the code now and just update it anyway when calling clk_core_get_phase, which would be much simple and enough. Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> Acked-by: Jerome Brunet <jbrunet@baylibre.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-24clk: migrate the count of orphaned clocks at initJerome Brunet1-16/+21
commit 99652a469df19086d594e8e89757d4081a812789 upstream. The orphan clocks reparents should migrate any existing count from the orphan clock to its new acestor clocks, otherwise we may have inconsistent counts in the tree and end-up with gated critical clocks Assuming we have two clocks, A and B. * Clock A has CLK_IS_CRITICAL flag set. * Clock B is an ancestor of A which can gate. Clock B gate is left enabled by the bootloader. Step 1: Clock A is registered. Since it is a critical clock, it is enabled. The clock being still an orphan, no parent are enabled. Step 2: Clock B is registered and reparented to clock A (potentially through several other clocks). We are now in situation where the enable count of clock A is 1 while the enable count of its ancestors is 0, which is not good. Step 3: in lateinit, clk_disable_unused() is called, the enable_count of clock B being 0, clock B is gated and and critical clock A actually gets disabled. This situation was found while adding fdiv_clk gates to the meson8b platform. These clocks parent clk81 critical clock, which is the mother of all peripheral clocks in this system. Because of the issue described here, the system is crashing when clk_disable_unused() is called. The situation is solved by reverting commit f8f8f1d04494 ("clk: Don't touch hardware when reparenting during registration"). To avoid breaking again the situation described in this commit description, enabling critical clock should be done before walking the orphan list. This way, a parent critical clock may not be accidentally disabled due to the CLK_OPS_PARENT_ENABLE mechanism. Fixes: f8f8f1d04494 ("clk: Don't touch hardware when reparenting during registration") Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Dong Aisheng <aisheng.dong@nxp.com> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Michael Turquette <mturquette@baylibre.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-24clk: Don't touch hardware when reparenting during registrationStephen Boyd1-2/+5
[ Upstream commit f8f8f1d04494d3a6546bee3f0618c4dba31d7b72 ] The orphan clocks reparent operation shouldn't touch the hardware if clocks are enabled, otherwise it may get a chance to disable a newly registered critical clock which triggers the warning below. Assuming we have two clocks: A and B, B is the parent of A. Clock A has flag: CLK_OPS_PARENT_ENABLE Clock B has flag: CLK_IS_CRITICAL Step 1: Clock A is registered, then it becomes orphan. Step 2: Clock B is registered. Before clock B reach the critical clock enable operation, orphan A will find the newly registered parent B and do reparent operation, then parent B will be finally disabled in __clk_set_parent_after() due to CLK_OPS_PARENT_ENABLE flag as there's still no users of B which will then trigger the following warning. WARNING: CPU: 0 PID: 0 at drivers/clk/clk.c:597 clk_core_disable+0xb4/0xe0 Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.11.0-rc1-00056-gdff1f66-dirty #1373 Hardware name: Generic DT based system Backtrace: [<c010c4bc>] (dump_backtrace) from [<c010c764>] (show_stack+0x18/0x1c) r6:600000d3 r5:00000000 r4:c0e26358 r3:00000000 [<c010c74c>] (show_stack) from [<c040599c>] (dump_stack+0xb4/0xe8) [<c04058e8>] (dump_stack) from [<c0125c94>] (__warn+0xd8/0x104) r10:c0c21cd0 r9:c048aa78 r8:00000255 r7:00000009 r6:c0c1cd90 r5:00000000 r4:00000000 r3:c0e01d34 [<c0125bbc>] (__warn) from [<c0125d74>] (warn_slowpath_null+0x28/0x30) r9:00000000 r8:ef00bf80 r7:c165ac4c r6:ef00bf80 r5:ef00bf80 r4:ef00bf80 [<c0125d4c>] (warn_slowpath_null) from [<c048aa78>] (clk_core_disable+0xb4/0xe0) [<c048a9c4>] (clk_core_disable) from [<c048be88>] (clk_core_disable_lock+0x20/0x2c) r4:000000d3 r3:c0e0af00 [<c048be68>] (clk_core_disable_lock) from [<c048c224>] (clk_core_disable_unprepare+0x14/0x28) r5:00000000 r4:ef00bf80 [<c048c210>] (clk_core_disable_unprepare) from [<c048c270>] (__clk_set_parent_after+0x38/0x54) r4:ef00bd80 r3:000010a0 [<c048c238>] (__clk_set_parent_after) from [<c048daa8>] (clk_register+0x4d0/0x648) r6:ef00d500 r5:ef00bf80 r4:ef00bd80 r3:ef00bfd4 [<c048d5d8>] (clk_register) from [<c048dc30>] (clk_hw_register+0x10/0x1c) r9:00000000 r8:00000003 r7:00000000 r6:00000824 r5:00000001 r4:ef00d500 [<c048dc20>] (clk_hw_register) from [<c048e698>] (_register_divider+0xcc/0x120) [<c048e5cc>] (_register_divider) from [<c048e730>] (clk_register_divider+0x44/0x54) r10:00000004 r9:00000003 r8:00000001 r7:00000000 r6:00000003 r5:00000001 r4:f0810030 [<c048e6ec>] (clk_register_divider) from [<c0d3ff58>] (imx7ulp_clocks_init+0x558/0xe98) r7:c0e296f8 r6:c165c808 r5:00000000 r4:c165c808 [<c0d3fa00>] (imx7ulp_clocks_init) from [<c0d24db0>] (of_clk_init+0x118/0x1e0) r10:00000001 r9:c0e01f68 r8:00000000 r7:c0e01f60 r6:ef7f8974 r5:ef0035c0 r4:00000006 [<c0d24c98>] (of_clk_init) from [<c0d04a50>] (time_init+0x2c/0x38) r10:efffed40 r9:c0d61a48 r8:c0e78000 r7:c0e07900 r6:ffffffff r5:c0e78000 r4:00000000 [<c0d04a24>] (time_init) from [<c0d00b8c>] (start_kernel+0x218/0x394) [<c0d00974>] (start_kernel) from [<6000807c>] (0x6000807c) r10:00000000 r9:410fc075 r8:6000406a r7:c0e0c930 r6:c0d61a44 r5:c0e07918 r4:c0e78294 We know that the clk isn't enabled with any sort of prepare_count here so we don't need to enable anything to prevent a race. And we're holding the prepare mutex so set_rate/set_parent can't race here either. Based on an earlier patch by Dong Aisheng. Fixes: fc8726a2c021 ("clk: core: support clocks which requires parents enable (part 2)") Cc: Michael Turquette <mturquette@baylibre.com> Cc: Shawn Guo <shawnguo@kernel.org> Reported-by: Dong Aisheng <aisheng.dong@nxp.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-22clk: Convert to using %pOF instead of full_nameRob Herring1-2/+2
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>
2017-04-22clk: Improve a size determination in two functionsMarkus Elfring1-2/+2
Replace the specification of two data structures by pointer dereferences as the parameter for the operator "sizeof" to make the corresponding size determination a bit safer according to the Linux coding style convention. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2017-04-22clk: Replace four seq_printf() calls by seq_putc()Markus Elfring1-5/+4
Four single characters should be put into a sequence. Thus use the corresponding function "seq_putc". 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>
2017-04-12clk: aggregate return codes of notify chainsPeter De Schrijver1-0/+2
In case there are multiple notify chains for the same clocks (because they were registered by different users), we need to propagate potential failure of any single one of them to the caller. Otherwise we eg risk violating the V/f curve when a notifier is used for DVFS. Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@baylibre.com>
2017-04-12clk: add clk_possible_parents debugfs filePeter De Schrijver1-0/+32
For validation purposes, it's often useful to be able to retrieve the list of possible parents in userspace. Add a debugfs file for every clock which has more than 1 possible parent. Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com> Reviewed-by: Jon Mayo <jmayo@nvidia.com> [sboyd@codeaurora.org: Remove useless cast from void and extra newline] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@baylibre.com>
2017-03-07clk: core: Copy connection idLeonard Crestez1-1/+2
Some drivers use sprintf to build clk connection id names but the clk core will save those strings and occasionally print them back. Duplicate the con_id strings instead of fixing all the users. Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-08-31clk: core: Force setting the phase delay when no changeJean-Francois Moine1-5/+0
This patch reverts commit 023bd7166be0 ("clk: skip unnecessary set_phase if nothing to do"), fixing two problems: * in some SoCs, the hardware phase delay depends on the rate ratio of the clock and its parent. So, changing this ratio may imply to set new hardware values, even if the logical delay is the same. * when the delay was the same as previously, an error was returned. Signed-off-by: Jean-Francois Moine <moinejf@free.fr> Fixes: 023bd7166be0 ("clk: skip unnecessary set_phase if nothing to do") Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-08-26clk: Simplify __of_clk_get_hw_from_provider()Stephen Boyd1-11/+6
__of_clk_get_hw_from_provider() is confusing because it will return EPROBE_DEFER if there isn't a ->get() or ->get_hw() function pointer in a provider. That's just a bug though, and we used to NULL pointer exception when ->get() was missing anyway, so let's make this more obvious that they're not optional. The assumption is that most providers will implement ->get_hw() so we only fallback to the ->get() function if necessary. This clarifies the intent and removes any possibility of probe defer happening if clk providers are buggy. Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-08-16clk: Return errors from clk providers in __of_clk_get_from_provider()Stephen Boyd1-4/+5
Before commit 0861e5b8cf80 (clk: Add clk_hw OF clk providers, 2016-02-05) __of_clk_get_from_provider() would return an error pointer of the provider's choosing if there was a provider registered and EPROBE_DEFER otherwise. After that commit, it would return EPROBE_DEFER regardless of whether or not the provider returned an error. This is odd and can lead to behavior where clk consumers keep probe deferring when they should be seeing some other error. Let's restore the previous behavior where we only return EPROBE_DEFER when there isn't a provider in our of_clk_providers list. Otherwise, return the error from the last provider we find that matches the node. Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com> Fixes: 0861e5b8cf80 ("clk: Add clk_hw OF clk providers") Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-08-13clk: use ERR_CAST() for __clk_create_clk()Masahiro Yamada1-1/+1
This code is clear enough, but the intention will be even clearer with this. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-08-13clk: core: Avoid double initialization of clocksRicardo Ribalda Delgado1-0/+4
Some clock providers can be initialized via of_clk_init() and also via platform device probe. Avoid double initialization of them by setting the OF_POPULATED flag. Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-08-12clk: migrate ref counts when orphans are reunitedMichael Turquette1-2/+10
It's always nice to see families reunited, and this is equally true when talking about parent clocks and their children. However, if the orphan clk had a positive prepare_count or enable_count, then we would not migrate those counts up the parent chain correctly. This has manifested with the recent critical clocks feature, which often enables clocks very early, before their parents have been registered. Fixed by replacing the call to clk_core_reparent with calls to __clk_set_parent_{before,after}. Cc: James Liao <jamesjj.liao@mediatek.com> Cc: Erin Lo <erin.lo@mediatek.com> Signed-off-by: Michael Turquette <mturquette@baylibre.com> [sboyd@codeaurora.org: Recalc accuracies and rates too] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-07-02clk: core: support clocks which requires parents enable (part 2)Dong Aisheng1-15/+33
On Freescale i.MX7D platform, all clocks operations, including enable/disable, rate change and re-parent, requires its parent clock on. Current clock core can not support it well. This patch adding flag CLK_OPS_PARENT_ENABLE to handle this special case in clock core that enable its parent clock firstly for each operation and disable it later after operation complete. The patch part 2 fixes set clock rate and set parent while its parent is off. The most special case is for set_parent() operation which requires all parents including both old and new one to be enabled at the same time during the operation. Cc: Michael Turquette <mturquette@baylibre.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> [sboyd@codeaurora.org: Move set_rate tracepoint after prepare_enable] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-07-02clk: core: support clocks which requires parents enable (part 1)Dong Aisheng1-0/+5
On Freescale i.MX7D platform, all clocks operations, including enable/disable, rate change and re-parent, requires its parent clock enable. Current clock core can not support it well. This patch introduce a new flag CLK_OPS_PARENT_ENABLE to handle this special case in clock core that enable its parent clock firstly for each operation and disable it later after operation complete. The patch part 1 fixes the possible disabling clocks while its parent is off during kernel booting phase in clk_disable_unused_subtree(). Before the completion of kernel booting, clock tree is still not built completely, there may be a case that the child clock is on but its parent is off which could be caused by either HW initial reset state or bootloader initialization. Taking bootloader as an example, we may enable all clocks in HW by default. And during kernel booting time, the parent clock could be disabled in its driver probe due to calling clk_prepare_enable and clk_disable_unprepare. Because it's child clock is only enabled in HW while its SW usecount in clock tree is still 0, so clk_disable of parent clock will gate the parent clock in both HW and SW usecount ultimately. Then there will be a child clock is still on in HW but its parent is already off. Later in clk_disable_unused(), this clock disable accessing while its parent off will cause system hang due to the limitation of HW which must require its parent on. This patch simply enables the parent clock first before disabling if flag CLK_OPS_PARENT_ENABLE is set in clk_disable_unused_subtree(). This is a simple solution and only affects booting time. After kernel booting up the clock tree is already created, there will be no case that child is off but its parent is off. So no need do this checking for normal clk_disable() later. Cc: Michael Turquette <mturquette@baylibre.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-07-02clk: move clk_disable_unused after clk_core_disable_unprepare functionDong Aisheng1-98/+98
No function level change, just moving code place. clk_disable_unused function will need to call clk_core_prepare_enable/ clk_core_disable_unprepare when adding CLK_OPS_PARENT_ENABLE features. So move it after clk_core_disable_unprepare to avoid adding forward declared functions later. Cc: Michael Turquette <mturquette@baylibre.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-07-02clk: introduce clk_core_enable_lock and clk_core_disable_lock functionsDong Aisheng1-22/+63
This can be useful when clock core wants to enable/disable clocks. Then we don't have to convert the struct clk_core to struct clk to call clk_enable/clk_disable which is a bit un-align with exist using. And after introduce clk_core_{enable|disable}_lock, we can refine clk_enable and clk_disable a bit. As well as clk_core_{enable|disable}_lock, we also added clk_core_{prepare|unprepare}_lock and clk_core_prepare_enable/ clk_core_unprepare_disable for clock core to easily use. Cc: Michael Turquette <mturquette@baylibre.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-06-21clk: correct comments for __clk_determine_ratePeng Fan1-3/+1
Correct comments for __clk_determine_rate. Signed-off-by: Peng Fan <van.freenix@gmail.com> Cc: Michael Turquette <mturquette@baylibre.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-06-21clk: Remove unused variableLee Jones1-2/+1
Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-06-17Merge commit 'f17a0dd1c2e0' into clk-nextMichael Turquette1-4/+4
2016-06-15clk: Use _rcuidle suffix to allow clk_core_enable() to used from idlePaul E. McKenney1-2/+2
This commit fixes the RCU use-from-idle bug corresponding the following splat: > [ INFO: suspicious RCU usage. ] > 4.6.0-rc5-next-20160426+ #1127 Not tainted > ------------------------------- > include/trace/events/clk.h:45 suspicious rcu_dereference_check() usage! > > other info that might help us debug this: > > > RCU used illegally from idle CPU! > rcu_scheduler_active = 1, debug_locks = 0 > RCU used illegally from extended quiescent state! > 2 locks held by swapper/0/0: > #0: (&oh->hwmod_key#30){......}, at: [<c0121afc>] omap_hwmod_enable+0x18/0x44 > #1: (enable_lock){......}, at: [<c0630684>] clk_enable_lock+0x18/0x124 > > stack backtrace: > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1127 > Hardware name: Generic OMAP36xx (Flattened Device Tree) > [<c0110290>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14) > [<c010c3a8>] (show_stack) from [<c047fd68>] (dump_stack+0xb0/0xe4) > [<c047fd68>] (dump_stack) from [<c06315c0>] (clk_core_enable+0x1e0/0x36c) > [<c06315c0>] (clk_core_enable) from [<c0632298>] (clk_enable+0x1c/0x38) > [<c0632298>] (clk_enable) from [<c01204e0>] (_enable_clocks+0x18/0x7c) > [<c01204e0>] (_enable_clocks) from [<c012137c>] (_enable+0x114/0x2ec) > [<c012137c>] (_enable) from [<c0121b08>] (omap_hwmod_enable+0x24/0x44) > [<c0121b08>] (omap_hwmod_enable) from [<c0122ad0>] (omap_device_enable+0x3c/0x90) > [<c0122ad0>] (omap_device_enable) from [<c0122b34>] (_od_runtime_resume+0x10/0x38) > [<c0122b34>] (_od_runtime_resume) from [<c052cc00>] (__rpm_callback+0x2c/0x60) > [<c052cc00>] (__rpm_callback) from [<c052cc54>] (rpm_callback+0x20/0x80) > [<c052cc54>] (rpm_callback) from [<c052df7c>] (rpm_resume+0x3d0/0x6f0) > [<c052df7c>] (rpm_resume) from [<c052e2e8>] (__pm_runtime_resume+0x4c/0x64) > [<c052e2e8>] (__pm_runtime_resume) from [<c04bf2c4>] (omap2_gpio_resume_after_idle+0x54/0x68) > [<c04bf2c4>] (omap2_gpio_resume_after_idle) from [<c01269dc>] (omap3_enter_idle_bm+0xfc/0x1ec) > [<c01269dc>] (omap3_enter_idle_bm) from [<c0601888>] (cpuidle_enter_state+0x80/0x3d4) > [<c0601888>] (cpuidle_enter_state) from [<c0183b08>] (cpu_startup_entry+0x198/0x3a0) > [<c0183b08>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8) > [<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c) Reported-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Guenter Roeck <linux@roeck-us.net> Cc: Russell King <linux@arm.linux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Michael Turquette <mturquette@baylibre.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: <linux-omap@vger.kernel.org> Cc: <linux-arm-kernel@lists.infradead.org> Cc: <linux-clk@vger.kernel.org>
2016-06-15clk: Add _rcuidle tracepoints to allow clk_core_disable() use from idlePaul E. McKenney1-2/+2
This commit adds an _rcuidle suffix to a pair of trace events to prevent the following splat: > =============================== > [ INFO: suspicious RCU usage. ] > 4.6.0-rc5-next-20160426+ #1114 Not tainted > ------------------------------- > include/trace/events/clk.h:59 suspicious rcu_dereference_check() usage! > > other info that might help us debug this: > > > RCU used illegally from idle CPU! > rcu_scheduler_active = 1, debug_locks = 0 > RCU used illegally from extended quiescent state! > 2 locks held by swapper/0/0: > #0: (&oh->hwmod_key#30){......}, at: [<c0121b40>] omap_hwmod_idle+0x18/0x44 > #1: (enable_lock){......}, at: [<c0630998>] clk_enable_lock+0x18/0x124 > > stack backtrace: > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1114 > Hardware name: Generic OMAP36xx (Flattened Device Tree) > [<c0110290>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14) > [<c010c3a8>] (show_stack) from [<c047fd68>] (dump_stack+0xb0/0xe4) > [<c047fd68>] (dump_stack) from [<c0631618>] (clk_core_disable+0x17c/0x348) > [<c0631618>] (clk_core_disable) from [<c0632774>] (clk_disable+0x24/0x30) > [<c0632774>] (clk_disable) from [<c0120590>] (_disable_clocks+0x18/0x7c) > [<c0120590>] (_disable_clocks) from [<c0121680>] (_idle+0x12c/0x230) > [<c0121680>] (_idle) from [<c0121b4c>] (omap_hwmod_idle+0x24/0x44) > [<c0121b4c>] (omap_hwmod_idle) from [<c0122c24>] (omap_device_idle+0x3c/0x90) > [<c0122c24>] (omap_device_idle) from [<c052cc00>] (__rpm_callback+0x2c/0x60) > [<c052cc00>] (__rpm_callback) from [<c052cc54>] (rpm_callback+0x20/0x80) > [<c052cc54>] (rpm_callback) from [<c052d150>] (rpm_suspend+0x100/0x768) > [<c052d150>] (rpm_suspend) from [<c052ec58>] (__pm_runtime_suspend+0x64/0x84) > [<c052ec58>] (__pm_runtime_suspend) from [<c04bf25c>] (omap2_gpio_prepare_for_idle+0x5c/0x70) > [<c04bf25c>] (omap2_gpio_prepare_for_idle) from [<c0125568>] (omap_sram_idle+0x140/0x244) > [<c0125568>] (omap_sram_idle) from [<c01269dc>] (omap3_enter_idle_bm+0xfc/0x1ec) > [<c01269dc>] (omap3_enter_idle_bm) from [<c0601bdc>] (cpuidle_enter_state+0x80/0x3d4) > [<c0601bdc>] (cpuidle_enter_state) from [<c0183b08>] (cpu_startup_entry+0x198/0x3a0) > [<c0183b08>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8) > [<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c) Reported-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Guenter Roeck <linux@roeck-us.net> Cc: Russell King <linux@arm.linux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Michael Turquette <mturquette@baylibre.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: <linux-omap@vger.kernel.org> Cc: <linux-arm-kernel@lists.infradead.org> Cc: <linux-clk@vger.kernel.org>
2016-05-20clk: fix critical clock lockingMaxime Ripard1-0/+5
The critical clock handling in __clk_core_init isn't taking the enable lock before calling clk_core_enable, which in turns triggers the warning in the lockdep_assert_held call in that function when lockep is enabled. Add the calls to clk_enable_lock/unlock to make sure it doesn't happen. Fixes: 32b9b1096186 ("clk: Allow clocks to be marked as CRITICAL") Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Reviewed-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-05-03clk: fix comment of devm_clk_hw_register()Masahiro Yamada1-1/+1
Unlike devm_clk_register(), devm_clk_hw_register() returns integer. So, the statement "Clocks returned from this function ..." sounds odd. Adjust the comment for this new API. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-22Merge branch 'clk-hw-register' (early part) into clk-nextStephen Boyd1-4/+167
* 'clk-hw-register' (early part): clk: fixed-rate: Add hw based registration APIs clk: gpio: Add hw based registration APIs clk: composite: Add hw based registration APIs clk: fractional-divider: Add hw based registration APIs clk: fixed-factor: Add hw based registration APIs clk: mux: Add hw based registration APIs clk: gate: Add hw based registration APIs clk: divider: Add hw based registration APIs clkdev: Add clk_hw based registration APIs clk: Add clk_hw OF clk providers clk: Add {devm_}clk_hw_{register,unregister}() APIs clkdev: Remove clk_register_clkdevs()
2016-04-20clk: Add clk_hw OF clk providersStephen Boyd1-4/+81
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 an OF node. Currently we ask the OF provider to give us a struct clk pointer for some clkspec, turn that struct clk into a struct clk_hw and then allocate a new struct clk to return to the caller. Let's add a clk_hw based OF provider hook that returns a struct clk_hw directly, so that we skip the intermediate step of converting from struct clk to struct clk_hw. Eventually when we've converted all OF clk providers to struct clk_hw based APIs we can remove the struct clk based ones. It should also be noted that we change the onecell provider to have a flex array instead of a pointer for the array of clk_hw pointers. This allows providers to allocate one structure of the correct length in one step instead of two. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-20clk: Add {devm_}clk_hw_{register,unregister}() APIsStephen Boyd1-0/+86
We've largely split the clk consumer and provider APIs along struct clk and struct clk_hw, but clk_register() still returns a struct clk pointer for each struct clk_hw that's registered. Eventually we'd like to only allocate struct clks when there's a user, because struct clk is per-user now, so clk_register() needs to change. Let's add new APIs to register struct clk_hws, but this time we'll hide the struct clk from the caller by returning an int error code. Also add an unregistration API that takes the clk_hw structure that was passed to the registration API. This way provider drivers never have to deal with a struct clk pointer unless they're using the clk consumer APIs. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-09clk: Provide OF helper to mark clocks as CRITICALLee Jones1-0/+35
This call matches clocks which have been marked as critical in DT and sets the appropriate flag. These flags can then be used to mark the clock core flags appropriately prior to registration. Legacy bindings requiring this feature must add the clock-critical property to their binding descriptions, as it is not a part of common-clock binding. Cc: devicetree@vger.kernel.org Signed-off-by: Lee Jones <lee.jones@linaro.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@baylibre.com> Link: lkml.kernel.org/r/1455225554-13267-4-git-send-email-mturquette@baylibre.com
2016-04-09clk: WARN_ON about to disable a critical clockLee Jones1-0/+6
Signed-off-by: Lee Jones <lee.jones@linaro.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@baylibre.com> Link: lkml.kernel.org/r/1455225554-13267-3-git-send-email-mturquette@baylibre.com
2016-04-09clk: Allow clocks to be marked as CRITICALLee Jones1-0/+5
Critical clocks are those which must not be gated, else undefined or catastrophic failure would occur. Here we have chosen to ensure the prepare/enable counts are correctly incremented, so as not to confuse users with enabled clocks with no visible users. Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Michael Turquette <mturquette@baylibre.com> Link: lkml.kernel.org/r/1455225554-13267-2-git-send-email-mturquette@baylibre.com
2016-02-27clk: Make of_clk_get_parent_count() return unsigned intsStephen Boyd1-2/+14
Russell King recently pointed out a bug in the clk-gpio code where it fails to register the clk if of_clk_get_parent_count() returns an error because the "clocks" property isn't present in the DT node. If we're trying to count parents from DT we'd like to know the count, not if there is a "clocks" property or not. Furthermore, some drivers are assigning the return value to their clk_init_data::num_parents member which is unsigned, leading to potentially large numbers of parents when the property isn't present. Let's change the API to return an unsigned int instead of an int. All the callers just want to know the count anyway, and this avoids the bug that was in the clk-gpio driver. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-26clk: Ignore disabled DT clock providersGeert Uytterhoeven1-0/+3
of_clk_init() uses for_each_matching_node_and_match() to find clock providers, which returns all matching device nodes, whether they are enabled or not. Hence clock providers that are disabled explicitly in DT using e.g. "status = "disabled"; are still activated. Add a check to ignore device nodes that are not enabled, like of_irq_init() does. Reported-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-26clk: skip unnecessary set_phase if nothing to doShawn Lin1-0/+5
Let's compare the degrees from clk_set_rate with clk->core->phase. If the requested degrees is already there, skip the following steps. Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> [sboyd@codeaurora.org: s/drgrees/degrees/ in commit text] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-23clk: Update some outdated commentsStephen Boyd1-3/+3
__clk_init() was renamed to __clk_core_init() but these comments weren't updated. Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-23Revert "clk: avoid circular clock topology"Stephen Boyd1-40/+0
This reverts commit 858d5881564026cbc4e6f5e25ae878a27df5d4c9. Joachim reports that this commit breaks lpc18xx boot. This is because the hardware has circular clk topology where PLLs can feed into dividers and the same dividers can feed into the PLLs. The hardware is designed this way so that you can choose to put the divider before the PLL or after the PLL depending on what you configure to be the parent of the divider and what you configure to be the parent of the PLL. So let's drop this patch for now because we have hardware that actually has loops. A future patch could check for circular parents when we change parents and fail the switch, but that's probably best left to some debugging Kconfig option so that we don't suffer the sanity checking cost all the time. Reported-by: Joachim Eastwood <manabian@gmail.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-18clk: Make of_clk_get_from_provider() available to modulesAndrew F. Davis1-0/+1
Export symbol of_clk_get_from_provider so it can be used in loadable kernel modules Signed-off-by: Andrew F. Davis <afd@ti.com> Signed-off-by: Michael Turquette <mturquette@baylibre.com>
2016-02-09clk: fix __clk_init_parent() for single parent clocksMasahiro Yamada1-1/+1
Before commit b3d192d5121f ("clk: simplify __clk_init_parent()"), __clk_init_parent() called .get_parent() only for multi-parent clocks. That commit changed the behavior to call .get_parent() if available even for single-parent clocks and root clocks. It turned out a problem because there are some single-parent clocks that implement .get_parent() callback and return non-zero index. The SOCFPGA clock is the case; the commit broke the SOCFPGA boards. To keep the original behavior, invoke .get_parent() only when num_parents is greater than 1. Fixes: b3d192d5121f ("clk: simplify __clk_init_parent()") Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reported-by: Dinh Nguyen <dinguyen@opensource.altera.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-07clk: Deprecate CLK_IS_ROOTStephen Boyd1-3/+3
We don't use CLK_IS_ROOT but in a few places in the common clk framework core. Let's replace those checks with a check for the number of parents a clk has instead of the flag, freeing up one flag for something else. We don't remove the flag yet so that things keep building, but we'll remove it once all drivers have removed their flag usage. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-02clk: unlock for handling unregistered clockInsu Yun1-2/+2
If clock is already unregistered, it returns with holding lock. It needs to be unlocked. Signed-off-by: Insu Yun <wuninsu@gmail.com> [sboyd@codeaurora.org: Use goto instead] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-02clk: slightly optimize clk_core_set_parent()Masahiro Yamada1-1/+1
If clk_fetch_parent_index() fails, p_rate is unused. Move the assignment after the error checking. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>