It seems to be usual for MFD devices that the created 'clock sub-device'
do not have own DT node. The clock provider information is usually in the
main device node which is owned by the MFD device. Change the devm variant
of clk of-provider registration to check the parent device node if given
device has no own node or if the node does not contain the #clock-cells
property. In such case use the parent node if it contains the #clock-cells.
Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
[sboyd@kernel.org: Add some comment in the code and pull out logic into
a single function to return the provider device_node pointer]
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Document the devm_of_clk_del_provider and the
devm_of_clk_add_hw_provider functions.
Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
[sboyd@kernel.org: Comply with kernel-doc formatting]
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
The normal style is to use 'core' for struct clk_core pointers and to
directly access the core pointer from the clk_hw pointer when we're
within the common clk framework. Update the patches to make it a bit
easier to handle.
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
The clock gate restore context function enables or disables
the gate clocks based on the enable_count. This is done in cases
where the clock context is lost and based on the enable_count
the clock either needs to be enabled/disabled.
Signed-off-by: Keerthy <j-keerthy@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Deep enough power saving mode can result into losing context of the clock
registers also, and they need to be restored once coming back from the power
saving mode. Hence add functions to save/restore clock context.
Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Russ Dill <Russ.Dill@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>
We've added duty cycle support to the clk API so that clk signal
duty cycle ratios can be adjusted while taking into account things
like clk dividers and clk tree hierarchy. So far only one SoC has
implemented support for this, but I expect there will be more to
come in the future.
Outside of the core, we have the usual pile of clk driver updates
and additions. The Amlogic meson driver got the most lines in the
diffstat this time around because it added support for a whole bunch
of hardware and duty cycle configuration. After that the Rockchip PX30,
Qualcomm SDM845, and Renesas SoC drivers fill in a majority of the diff.
We're left with the collection of non-critical fixes after that. Overall
it looks pretty quiet this time.
Core:
- Clk duty cycle support
- Proper CLK_SET_RATE_GATE support throughout the tree
New Drivers:
- Actions Semi Owl series S700 SoC clk driver
- Qualcomm SDM845 display clock controller
- i.MX6SX ocram_s clk support
- Uniphier NAND, USB3 PHY, and SPI clk support
- Qualcomm RPMh clk driver
- i.MX7D mailbox clk support
- Maxim 9485 Programmable Clock Generator
- Expose 32 kHz PLL on PXA SoCs
- imx6sll GPIO clk gate support
- Atmel at91 I2S audio clk support
- SI544/SI514 clk on/off support
- i.MX6UL GPIO clock gates in CCM CCGR
- Renesas Crypto Engine clocks on R-Car H3
- Renesas clk support for the new RZ/N1D SoC
- Allwinner A64 display engine clock support
- Support for Rockchip's PX30 SoC
- Amlogic Meson axg PCIe and audio clocks
- Amlogic Meson GEN CLK on gxbb, gxl and axg
Updates:
- Remove an unused variable from Exynos4412 ISP driver
- Fix a thinko bug in SCMI clk division logic
- Add missing of_node_put()s in some i.MX clk drivers
- Tegra SDMMC clk jitter improvements with high speed signaling modes
- SPDX tagging for qcom and cs2000-cp drivers
- Stop leaking con ids in __clk_put()
- Fix a corner case in fixed factor clk probing where node is in DT but
parent clk is registered much later
- Marvell Armada 3700 clk_pm_cpu_get_parent() had an invalid return value
- i.MX clk init arrays removed in place of CLK_IS_CRITICAL
- Convert to CLK_IS_CRITICAL for i.MX51/53 driver
- Fix Tegra BPMP driver oops when xlating a NULL clk
- Proper default configuration for vic03 and vde clks on Tegra124
- Mark Tegra memory controller clks as critical
- Fix array bounds clamp in Tegra's emc determine_rate() op
- Ingenic i2s bit update and allow UDC clk to gate
- Fix name of aspeed SDC clk define to have only one 'CLK'
- Fix i.MX6QDL video clk parent
- Critical clk markings for qcom SDM845
- Fix Stratix10 mpu_free_clk and sdmmc_free_clk parents
- Mark Rockchip's pclk_rkpwm_pmu as critical clock, due to it supplying
the pwm used to drive the logic supply of the rk3399 core.
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Merge tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux
Pull clk updates from Stephen Boyd:
"The new and exciting feature this time around is in the clk core.
We've added duty cycle support to the clk API so that clk signal duty
cycle ratios can be adjusted while taking into account things like clk
dividers and clk tree hierarchy. So far only one SoC has implemented
support for this, but I expect there will be more to come in the
future.
Outside of the core, we have the usual pile of clk driver updates and
additions. The Amlogic meson driver got the most lines in the diffstat
this time around because it added support for a whole bunch of
hardware and duty cycle configuration. After that the Rockchip PX30,
Qualcomm SDM845, and Renesas SoC drivers fill in a majority of the
diff. We're left with the collection of non-critical fixes after that.
Overall it looks pretty quiet this time.
Core:
- Clk duty cycle support
- Proper CLK_SET_RATE_GATE support throughout the tree
New Drivers:
- Actions Semi Owl series S700 SoC clk driver
- Qualcomm SDM845 display clock controller
- i.MX6SX ocram_s clk support
- Uniphier NAND, USB3 PHY, and SPI clk support
- Qualcomm RPMh clk driver
- i.MX7D mailbox clk support
- Maxim 9485 Programmable Clock Generator
- expose 32 kHz PLL on PXA SoCs
- imx6sll GPIO clk gate support
- Atmel at91 I2S audio clk support
- SI544/SI514 clk on/off support
- i.MX6UL GPIO clock gates in CCM CCGR
- Renesas Crypto Engine clocks on R-Car H3
- Renesas clk support for the new RZ/N1D SoC
- Allwinner A64 display engine clock support
- support for Rockchip's PX30 SoC
- Amlogic Meson axg PCIe and audio clocks
- Amlogic Meson GEN CLK on gxbb, gxl and axg
Updates:
- remove an unused variable from Exynos4412 ISP driver
- fix a thinko bug in SCMI clk division logic
- add missing of_node_put()s in some i.MX clk drivers
- Tegra SDMMC clk jitter improvements with high speed signaling modes
- SPDX tagging for qcom and cs2000-cp drivers
- stop leaking con ids in __clk_put()
- fix a corner case in fixed factor clk probing where node is in DT
but parent clk is registered much later
- Marvell Armada 3700 clk_pm_cpu_get_parent() had an invalid return
value
- i.MX clk init arrays removed in place of CLK_IS_CRITICAL
- convert to CLK_IS_CRITICAL for i.MX51/53 driver
- fix Tegra BPMP driver oops when xlating a NULL clk
- proper default configuration for vic03 and vde clks on Tegra124
- mark Tegra memory controller clks as critical
- fix array bounds clamp in Tegra's emc determine_rate() op
- Ingenic i2s bit update and allow UDC clk to gate
- fix name of aspeed SDC clk define to have only one 'CLK'
- fix i.MX6QDL video clk parent
- critical clk markings for qcom SDM845
- fix Stratix10 mpu_free_clk and sdmmc_free_clk parents
- mark Rockchip's pclk_rkpwm_pmu as critical clock, due to it
supplying the pwm used to drive the logic supply of the rk3399
core"
* tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (85 commits)
clk: rockchip: Add pclk_rkpwm_pmu to PMU critical clocks in rk3399
clk: cs2000-cp: convert to SPDX identifiers
clk: scmi: Fix the rounding of clock rate
clk: qcom: Add display clock controller driver for SDM845
clk: mvebu: armada-37xx-periph: Remove unused var num_parents
clk: samsung: Remove unused mout_user_aclk400_mcuisp_p4x12 variable
clk: actions: Add S700 SoC clock support
dt-bindings: clock: Add S700 support for Actions Semi Soc's
clk: actions: Add missing REGMAP_MMIO dependency
clk: uniphier: add clock frequency support for SPI
clk: uniphier: add more USB3 PHY clocks
clk: uniphier: add NAND 200MHz clock
clk: tegra: make sdmmc2 and sdmmc4 as sdmmc clocks
clk: tegra: Add sdmmc mux divider clock
clk: tegra: Refactor fractional divider calculation
clk: tegra: Fix includes required by fence_udelay()
clk: imx6sll: fix missing of_node_put()
clk: imx6ul: fix missing of_node_put()
clk: imx: add ocram_s clock for i.mx6sx
clk: mvebu: armada-37xx-periph: Fix wrong return value in get_parent
...
* clk-qcom-rpmh:
: - Qualcomm RPMh clk driver
clk: qcom: clk-rpmh: Add QCOM RPMh clock driver
* clk-qcom-spdx:
: - SPDX tagging for qcom
clk: qcom: Update SPDX headers for common files
* clk-con-id-leak:
: - Stop leaking con ids in __clk_put()
clk: core: Potentially free connection id
* clk-fixed-factor-populated:
: - Fix a corner case in fixed factor clk probing where node is in DT but
: parent clk is registered much later
clk: clk-fixed-factor: Clear OF_POPULATED flag in case of failure
* clk-mvebu-periph-parent:
: - Marvell Armada 3700 clk_pm_cpu_get_parent() had an invalid return value
clk: mvebu: armada-37xx-periph: Remove unused var num_parents
clk: mvebu: armada-37xx-periph: Fix wrong return value in get_parent
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: 253160a8ad ("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>
The last-minute fold-in of the ENTRY() macro did change behavior:
instead of printing the symbolic name (e.g. "CLK_IS_BASIC"), it prints
the expansion of it (e.g. "(1UL << (5))").
Use "#" instead of __stringify() to fix this.
Fixes: a6059ab981 ("clk: Show symbolic clock flags in debugfs")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Add the possibility to apply and query the clock signal duty cycle ratio.
This is useful when the duty cycle of the clock signal depends on some
other parameters controlled by the clock framework.
For example, the duty cycle of a divider may depends on the raw divider
setting (ratio = N / div) , which is controlled by the CCF. In such case,
going through the pwm framework to control the duty cycle ratio of this
clock would be a burden.
A clock provider is not required to implement the operation to set and get
the duty cycle. If it does not implement .get_duty_cycle(), the ratio is
assumed to be 50%.
This change also adds a new flag, CLK_DUTY_CYCLE_PARENT. This flag should
be used to indicate that a clock, such as gates and muxes, may inherit
the duty cycle ratio of its parent clock. If a clock does not provide a
get_duty_cycle() callback and has CLK_DUTY_CYCLE_PARENT, then the call
will be directly forwarded to its parent clock, if any. For
set_duty_cycle(), the clock should also have CLK_SET_RATE_PARENT for the
call to be forwarded
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Link: lkml.kernel.org/r/20180619144141.8506-1-jbrunet@baylibre.com
CLK_SET_RATE_GATE should prevent any operation which may result in a rate
change or glitch while the clock is prepared/enabled.
IOW, the following sequence is not allowed anymore with CLK_SET_RATE_GATE:
* clk_get()
* clk_prepare_enable()
* clk_get_rate()
* clk_set_rate()
At the moment this is enforced on the leaf clock of the operation, not
along the tree. This problematic because, if a PLL has the CLK_RATE_GATE,
it won't be enforced if the clk_set_rate() is called on its child clocks.
Using clock rate protection, we can now enforce CLK_SET_RATE_GATE along the
clock tree
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Tested-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Link: lkml.kernel.org/r/20180619134051.16726-3-jbrunet@baylibre.com
As we move stuff around, some doc references are broken. Fix some of
them via this script:
./scripts/documentation-file-ref-check --fix
Manually checked if the produced result is valid, removing a few
false-positives.
Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>
general cleanups, but nothing too major. The majority of the diff goes to
two SoCs, Actions Semi and Qualcomm. A brand new driver is introduced for
Actions Semi so it takes up some lines to add all the different types, and
the Qualcomm diff is there because we add support for two SoCs and it's quite
a bit of data.
Otherwise the big driver updates are on TI Davinci and Amlogic platforms. And
then the long tail of driver updates for various fixes and stuff follows
after that.
Core:
- debugfs cleanups removing error checking and an unused provider API
- Removal of a clk init typedef that isn't used
- Usage of match_string() to simplify parent string name matching
- OF clk helpers moved to their own file (linux/of_clk.h)
- Make clk warnings more readable across kernel versions
New Drivers:
- Qualcomm SDM845 GCC and Video clk controllers
- Qualcomm MSM8998 GCC
- Actions Semi S900 SoC support
- Nuvoton npcm750 microcontroller clks
- Amlogic axg AO clock controller
Removed Drivers:
- Deprecated Rockchip clk-gate driver
Updates:
- debugfs functions stopped checking return values
- Support for the MSIOF module clocks on Rensas R-Car M3-N
- Support for the new Rensas RZ/G1C and R-Car E3 SoCs
- Qualcomm GDSC, RCG, and PLL updates for clk changes in new SoCs
- Berlin and Amlogic SPDX tagging
- Usage of of_clk_get_parent_count() in more places
- Proper implementation of the CDEV1/2 clocks on Tegra20
- Allwinner H6 PRCM clock support and R40 EMAC support
- Add critical flag to meson8b's fdiv2 as temporary fixup for ethernet
- Round closest support for meson's mpll driver
- Support for meson8b nand clocks and gxbb video decoder clocks
- Mediatek mali clks
- STM32MP1 fixes
- Uniphier LD11/LD20 stream demux system clock
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Merge tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux
Pull clk updates from Stephen Boyd:
"This time we have a good set of changes to the core framework that do
some general cleanups, but nothing too major. The majority of the diff
goes to two SoCs, Actions Semi and Qualcomm. A brand new driver is
introduced for Actions Semi so it takes up some lines to add all the
different types, and the Qualcomm diff is there because we add support
for two SoCs and it's quite a bit of data.
Otherwise the big driver updates are on TI Davinci and Amlogic
platforms. And then the long tail of driver updates for various fixes
and stuff follows after that.
Core:
- debugfs cleanups removing error checking and an unused provider API
- Removal of a clk init typedef that isn't used
- Usage of match_string() to simplify parent string name matching
- OF clk helpers moved to their own file (linux/of_clk.h)
- Make clk warnings more readable across kernel versions
New Drivers:
- Qualcomm SDM845 GCC and Video clk controllers
- Qualcomm MSM8998 GCC
- Actions Semi S900 SoC support
- Nuvoton npcm750 microcontroller clks
- Amlogic axg AO clock controller
Removed Drivers:
- Deprecated Rockchip clk-gate driver
Updates:
- debugfs functions stopped checking return values
- Support for the MSIOF module clocks on Rensas R-Car M3-N
- Support for the new Rensas RZ/G1C and R-Car E3 SoCs
- Qualcomm GDSC, RCG, and PLL updates for clk changes in new SoCs
- Berlin and Amlogic SPDX tagging
- Usage of of_clk_get_parent_count() in more places
- Proper implementation of the CDEV1/2 clocks on Tegra20
- Allwinner H6 PRCM clock support and R40 EMAC support
- Add critical flag to meson8b's fdiv2 as temporary fixup for ethernet
- Round closest support for meson's mpll driver
- Support for meson8b nand clocks and gxbb video decoder clocks
- Mediatek mali clks
- STM32MP1 fixes
- Uniphier LD11/LD20 stream demux system clock"
* tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (134 commits)
clk: qcom: Export clk_fabia_pll_configure()
clk: bcm: Update and add Stingray clock entries
dt-bindings: clk: Update Stingray binding doc
clk-si544: Properly round requested frequency to nearest match
clk: ingenic: jz4770: Add 150us delay after enabling VPU clock
clk: ingenic: jz4770: Enable power of AHB1 bus after ungating VPU clock
clk: ingenic: jz4770: Modify C1CLK clock to disable CPU clock stop on idle
clk: ingenic: jz4770: Change OTG from custom to standard gated clock
clk: ingenic: Support specifying "wait for clock stable" delay
clk: ingenic: Add support for clocks whose gate bit is inverted
clk: use match_string() helper
clk: bcm2835: use match_string() helper
clk: Return void from debug_init op
clk: remove clk_debugfs_add_file()
clk: tegra: no need to check return value of debugfs_create functions
clk: davinci: no need to check return value of debugfs_create functions
clk: bcm2835: no need to check return value of debugfs_create functions
clk: no need to check return value of debugfs_create functions
clk: imx6: add EPIT clock support
clk: mvebu: use correct bit for 98DX3236 NAND
...
* clk-match-string:
clk: use match_string() helper
clk: bcm2835: use match_string() helper
* clk-ingenic:
clk: ingenic: jz4770: Add 150us delay after enabling VPU clock
clk: ingenic: jz4770: Enable power of AHB1 bus after ungating VPU clock
clk: ingenic: jz4770: Modify C1CLK clock to disable CPU clock stop on idle
clk: ingenic: jz4770: Change OTG from custom to standard gated clock
clk: ingenic: Support specifying "wait for clock stable" delay
clk: ingenic: Add support for clocks whose gate bit is inverted
* clk-si544-round-fix:
clk-si544: Properly round requested frequency to nearest match
* clk-bcm-stingray:
clk: bcm: Update and add Stingray clock entries
dt-bindings: clk: Update Stingray binding doc
* clk-imx7d:
clk: imx7d: reset parent for mipi csi root
clk: imx7d: fix mipi dphy div parent
* clk-hisi-stub:
clk/driver/hisi: Consolidate the Kconfig for the CLOCK_STUB
* clk-mvebu:
clk: mvebu: use correct bit for 98DX3236 NAND
* clk-imx6-epit:
clk: imx6: add EPIT clock support
* clk-debugfs-simple:
clk: Return void from debug_init op
clk: remove clk_debugfs_add_file()
clk: tegra: no need to check return value of debugfs_create functions
clk: davinci: no need to check return value of debugfs_create functions
clk: bcm2835: no need to check return value of debugfs_create functions
clk: no need to check return value of debugfs_create functions
match_string() returns the index of an array for a matching string,
which can be used instead of open coded variant.
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: linux-clk@vger.kernel.org
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
No one was using this api call, so remove it. If it is ever needed in
the future, a "raw" debugfs call can be used.
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
This cleans up the init code a lot, and there's no need to return an
error value based on the debugfs calls, especially as it turns out no
one was even looking at that return value. So it obviously wasn't that
important :)
Cc: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Since commit c08ee14cc6 ("clk: ti: change clock init to use
generic of_clk_init"), there is only a single (private) user left of the
(public) clk_init_cb typedef.
Hence expand its single user in the core clock code, and remove the
typedef.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Link: lkml.kernel.org/r/1523365565-17124-1-git-send-email-geert+renesas@glider.be
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: 15a02c1f6d ("clk: Add __clk_mux_determine_rate_closest")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
* clk-mvebu:
clk: mvebu: armada-38x: add support for missing clocks
clk: mvebu: cp110: Fix clock tree representation
* clk-phase:
clk: Don't show the incorrect clock phase
clk: update cached phase to respect the fact when setting phase
* clk-nxp:
clk: lpc32xx: Set name of regmap_config
* clk-mtk2712:
clk: mediatek: update clock driver of MT2712
dt-bindings: clock: add clocks for MT2712
* clk-qcom-rpmcc:
clk: qcom: rpmcc: Add support to XO buffered clocks
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>
...instead of open coding file operations followed by custom ->open()
callbacks per each attribute.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
When getting the clock related warnings, it is useful to know what
is the clock name that is causing the problem and the cause of the
problem.
Add the clock name and the the warning cause to the log, so that the
output becomes clearer like this:
[ 2.383969] ------------[ cut here ]------------
[ 2.388720] WARNING: CPU: 0 PID: 1 at drivers/clk/clk.c:814 clk_core_disable+0xd4/0xf8
[ 2.396658] uart4_ipg_gate already disabled
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Some clocks may need to initialize things, whatever it is, before
being able to properly operate. Move the .init() call before any
other callback, such recalc_rate() or get_phase(), so the clock
is properly setup before being used.
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
If we try to determine the rate of a pass-through clock (a clock which
does not implement .round_rate() nor .determine_rate()),
clk_core_round_rate_nolock() will directly forward the call to the
parent clock. In the particular case where the pass-through actually
does not have a parent, clk_core_round_rate_nolock() will directly
return 0 with the requested rate still set to the initial request
structure. This is interpreted as if the rate could be exactly achieved
while it actually cannot be adjusted.
This become a real problem when this particular pass-through clock is
the parent of a mux with the flag CLK_SET_RATE_PARENT set. The
pass-through clock will always report an exact match, get picked and
finally error when the rate is actually getting set.
This is fixed by setting the rate inside the req to 0 when core is NULL
in clk_core_round_rate_nolock() (same as in __clk_determine_rate() when
hw is NULL)
Fixes: 0f6cc2b8e9 ("clk: rework calls to round and determine rate callbacks")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
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 f8f8f1d044 ("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: f8f8f1d044 ("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>
It's found that the final phase set by driver doesn't match that of
the output from clk_summary:
dwmmc_rockchip fe310000.dwmmc: Successfully tuned phase to 346
mmc0: new ultra high speed SDR104 SDIO card at address 0001
cat /sys/kernel/debug/clk/clk_summary | grep sdio_sample
sdio_sample 0 1 0 50000000 0 0
It seems the cached core->phase isn't updated after the clk was
registered. So fix this issue by updating the core->phase if setting
phase successfully.
Fixes: 9e4d04adeb ("clk: add clk_core_set_phase_nolock function")
Cc: Stable <stable@vger.kernel.org>
Cc: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Tested-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
to the clk rate protection support added by Jerome Brunet. This feature
will allow consumers to lock in a certain rate on the output of a clk so
that things like audio playback don't hear pops when the clk frequency
changes due to shared parent clks changing rates. Currently the clk
API doesn't guarantee the rate of a clk stays at the rate you request
after clk_set_rate() is called, so this new API will allow drivers
to express that requirement. Beyond this, the core got some debugfs
pretty printing patches and a couple minor non-critical fixes.
Looking outside of the core framework diff we have some new driver
additions and the removal of a legacy TI clk driver. Both of these hit
high in the dirstat. Also, the removal of the asm-generic/clkdev.h file
causes small one-liners in all the architecture Kbuild files. Overall, the
driver diff seems to be the normal stuff that comes all the time to
fix little problems here and there and to support new hardware.
Core:
- Clk rate protection
- Symbolic clk flags in debugfs output
- Clk registration enabled clks while doing bookkeeping updates
New Drivers:
- Spreadtrum SC9860
- HiSilicon hi3660 stub
- Qualcomm A53 PLL, SPMI clkdiv, and MSM8916 APCS
- Amlogic Meson-AXG
- ASPEED BMC
Removed Drivers:
- TI OMAP 3xxx legacy clk (non-DT) support
- asm*/clkdev.h got removed (not really a driver)
Updates:
- Renesas FDP1-0 module clock on R-Car M3-W
- Renesas LVDS module clock on R-Car V3M
- Misc fixes to pr_err() prints
- Qualcomm MSM8916 audio fixes
- Qualcomm IPQ8074 rounded out support for more peripherals
- Qualcomm Alpha PLL variants
- Divider code was using container_of() on bad pointers
- Allwinner DE2 clks on H3
- Amlogic minor data fixes and dropping of CLK_IGNORE_UNUSED
- Mediatek clk driver compile test support
- AT91 PMC clk suspend/resume restoration support
- PLL issues fixed on si5351
- Broadcom IProc PLL calculation updates
- DVFS support for Armada mvebu CPU clks
- Allwinner fixed post-divider support
- TI clkctrl fixes and support for newer SoCs
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Merge tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux
Pull clk updates from Stephen Boyd:
"The core framework has a handful of patches this time around, mostly
due to the clk rate protection support added by Jerome Brunet.
This feature will allow consumers to lock in a certain rate on the
output of a clk so that things like audio playback don't hear pops
when the clk frequency changes due to shared parent clks changing
rates. Currently the clk API doesn't guarantee the rate of a clk stays
at the rate you request after clk_set_rate() is called, so this new
API will allow drivers to express that requirement.
Beyond this, the core got some debugfs pretty printing patches and a
couple minor non-critical fixes.
Looking outside of the core framework diff we have some new driver
additions and the removal of a legacy TI clk driver. Both of these hit
high in the dirstat. Also, the removal of the asm-generic/clkdev.h
file causes small one-liners in all the architecture Kbuild files.
Overall, the driver diff seems to be the normal stuff that comes all
the time to fix little problems here and there and to support new
hardware.
Summary:
Core:
- Clk rate protection
- Symbolic clk flags in debugfs output
- Clk registration enabled clks while doing bookkeeping updates
New Drivers:
- Spreadtrum SC9860
- HiSilicon hi3660 stub
- Qualcomm A53 PLL, SPMI clkdiv, and MSM8916 APCS
- Amlogic Meson-AXG
- ASPEED BMC
Removed Drivers:
- TI OMAP 3xxx legacy clk (non-DT) support
- asm*/clkdev.h got removed (not really a driver)
Updates:
- Renesas FDP1-0 module clock on R-Car M3-W
- Renesas LVDS module clock on R-Car V3M
- Misc fixes to pr_err() prints
- Qualcomm MSM8916 audio fixes
- Qualcomm IPQ8074 rounded out support for more peripherals
- Qualcomm Alpha PLL variants
- Divider code was using container_of() on bad pointers
- Allwinner DE2 clks on H3
- Amlogic minor data fixes and dropping of CLK_IGNORE_UNUSED
- Mediatek clk driver compile test support
- AT91 PMC clk suspend/resume restoration support
- PLL issues fixed on si5351
- Broadcom IProc PLL calculation updates
- DVFS support for Armada mvebu CPU clks
- Allwinner fixed post-divider support
- TI clkctrl fixes and support for newer SoCs"
* tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (125 commits)
clk: aspeed: Handle inverse polarity of USB port 1 clock gate
clk: aspeed: Fix return value check in aspeed_cc_init()
clk: aspeed: Add reset controller
clk: aspeed: Register gated clocks
clk: aspeed: Add platform driver and register PLLs
clk: aspeed: Register core clocks
clk: Add clock driver for ASPEED BMC SoCs
clk: mediatek: adjust dependency of reset.c to avoid unexpectedly being built
clk: fix reentrancy of clk_enable() on UP systems
clk: meson-axg: fix potential NULL dereference in axg_clkc_probe()
clk: Simplify debugfs registration
clk: Fix debugfs_create_*() usage
clk: Show symbolic clock flags in debugfs
clk: renesas: r8a7796: Add FDP clock
clk: Move __clk_{get,put}() into private clk.h API
clk: sunxi: Use CLK_IS_CRITICAL flag for critical clks
clk: Improve flags doc for of_clk_detect_critical()
arch: Remove clkdev.h asm-generic from Kbuild
clk: sunxi-ng: a83t: Add M divider to TCON1 clock
clk: Prepare to remove asm-generic/clkdev.h
...
* clk-aspeed:
clk: aspeed: Handle inverse polarity of USB port 1 clock gate
clk: aspeed: Fix return value check in aspeed_cc_init()
clk: aspeed: Add reset controller
clk: aspeed: Register gated clocks
clk: aspeed: Add platform driver and register PLLs
clk: aspeed: Register core clocks
clk: Add clock driver for ASPEED BMC SoCs
dt-bindings: clock: Add ASPEED constants
* clk-lock-UP:
clk: fix reentrancy of clk_enable() on UP systems
* clk-mediatek:
clk: mediatek: adjust dependency of reset.c to avoid unexpectedly being built
clk: mediatek: Fix all warnings for missing struct clk_onecell_data
clk: mediatek: fixup test-building of MediaTek clock drivers
clk: mediatek: group drivers under indpendent menu
* clk-allwinner:
clk: sunxi-ng: a83t: Add M divider to TCON1 clock
clk: sunxi-ng: fix the A64/H5 clock description of DE2 CCU
clk: sunxi-ng: add support for Allwinner H3 DE2 CCU
dt-bindings: fix the binding of Allwinner DE2 CCU of A83T and H3
clk: sunxi-ng: sun8i: a83t: Use sigma-delta modulation for audio PLL
clk: sunxi-ng: sun8i: a83t: Add /2 fixed post divider to audio PLL
clk: sunxi-ng: Support fixed post-dividers on NM style clocks
clk: sunxi-ng: sun50i: a64: Add 2x fixed post-divider to MMC module clocks
clk: sunxi-ng: Support fixed post-dividers on MP style clocks
clk: sunxi: Use PTR_ERR_OR_ZERO()
* clk-remove-asm-clkdev:
clk: Move __clk_{get,put}() into private clk.h API
clk: sunxi: Use CLK_IS_CRITICAL flag for critical clks
arch: Remove clkdev.h asm-generic from Kbuild
clk: Prepare to remove asm-generic/clkdev.h
blackfin: Use generic clkdev.h header
* clk-debugfs-fixes:
clk: Simplify debugfs registration
clk: Fix debugfs_create_*() usage
clk: Show symbolic clock flags in debugfs
clk: Improve flags doc for of_clk_detect_critical()
* clk-renesas:
clk: renesas: r8a7796: Add FDP clock
clk: renesas: cpg-mssr: Keep wakeup sources active during system suspend
clk: renesas: mstp: Keep wakeup sources active during system suspend
clk: renesas: r8a77970: Add LVDS clock
* clk-meson:
clk: meson-axg: fix potential NULL dereference in axg_clkc_probe()
clk: meson-axg: make local symbol axg_gp0_params_table static
clk: meson-axg: fix return value check in axg_clkc_probe()
clk: meson: mpll: use 64-bit maths in params_from_rate
clk: meson-axg: add clock controller drivers
clk: meson-axg: add clocks dt-bindings required header
dt-bindings: clock: add compatible variant for the Meson-AXG
clk: meson: make the spinlock naming more specific
clk: meson: gxbb: remove IGNORE_UNUSED from mmc clocks
clk: meson: gxbb: fix wrong clock for SARADC/SANA
* clk-at91:
clk: at91: pmc: Support backup for programmable clocks
clk: at91: pmc: Save SCSR during suspend
clk: at91: pmc: Wait for clocks when resuming
* clk-imx7ulp:
clk: Don't touch hardware when reparenting during registration
* clk-axigen:
clk: axi-clkgen: Round closest in round_rate() and recalc_rate()
clk: axi-clkgen: Correctly handle nocount bit in recalc_rate()
* clk-si5351:
clk: si5351: _si5351_clkout_reset_pll() can be static
clk: si5351: Do not enable parent clocks on probe
clk: si5351: Rename internal plls to avoid name collisions
clk: si5351: Apply PLL soft reset before enabling the outputs
clk: si5351: Add DT property to enable PLL reset
clk: si5351: implement remove handler
* clk-pxa:
clk: pxa: unbreak lookup of CLK_POUT
* clk-qcom-alpha-pll:
clk: qcom: add read-only alpha pll post divider operations
clk: qcom: support for 2 bit PLL post divider
clk: qcom: support Brammo type Alpha PLL
clk: qcom: support Huayra type Alpha PLL
clk: qcom: support for dynamic updating the PLL
clk: qcom: support for alpha mode configuration
clk: qcom: flag for 64 bit CONFIG_CTL
clk: qcom: fix 16 bit alpha support calculation
clk: qcom: support for alpha pll properties
* clk-check-ops-ptr:
clk: check ops pointer on clock register
* clk-protect-rate:
clk: fix set_rate_range when current rate is out of range
clk: add clk_rate_exclusive api
clk: cosmetic changes to clk_summary debugfs entry
clk: add clock protection mechanism to clk core
clk: use round rate to bail out early in set_rate
clk: rework calls to round and determine rate callbacks
clk: add clk_core_set_phase_nolock function
clk: take the prepare lock out of clk_core_set_parent
clk: fix incorrect usage of ENOSYS
* clk-omap:
clk: ti: Drop legacy clk-3xxx-legacy code
Reentrant calls to clk_enable() are not working on UP systems. This is
caused by the fact spin_trylock_irqsave() always returns true when
CONFIG_SMP=n (and CONFIG_DEBUG_SPINLOCK=n) which causes the reference
counting to not work correctly when clk_enable_lock() is called twice
before clk_enable_unlock() is called (this happens when clk_enable()
is called from within another clk_enable()).
This fixes the problem by skipping the call to spin_trylock_irqsave() on UP
systems and relying solely on reference counting. We also make sure to set
flags in this case so that we are not returning an uninitialized value.
Suggested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: David Lechner <david@lechnology.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
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>
Currently the virtual "clk_flags" file in debugfs shows the numeric
value of the top-level framework flags for the specified clock.
Hence the user must manually interpret these values.
Moreover, on big-endian 64-bit systems, the wrong half of the value is
shown, due to the cast from "unsigned long *" to "u32 *".
Fix both issues by showing the symbolic flag names instead.
Any non-standard flags are shown as a hex number.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
The "flags" parameter passed to of_clk_detect_critical() cannot be a
pointer to a real clk_core.flags field, as clk_core is private to the
clock framework internals.
Change the comment to refer to top-level framework flags instead.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Current clk_pm_runtime_put is using pm_runtime_put_sync which
is not safe to be called in clk_core_is_enabled as it should
be able to run in atomic context.
Thus use pm_runtime_put instead which is atomic safe.
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Fixes: 9a34b45397 ("clk: Add support for runtime PM")
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
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: fc8726a2c0 ("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>
Calling clk_core_set_rate() with core->req_rate is basically a no-op
because of the early bail-out mechanism.
This may leave the clock in inconsistent state if the rate is out the
requested range. Calling clk_core_set_rate() with the closest rate
limit could solve the problem but:
- The underlying determine_rate() callback needs to account for this
corner case (rounding within the range, if possible)
- if only round_rate() is available, we rely on luck unfortunately.
Fixes: 1c8e600440 ("clk: Add rate constraints to clocks")
Tested-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Link: lkml.kernel.org/r/20171201215200.23523-11-jbrunet@baylibre.com
Using clock rate protection, we can now provide a way for clock consumer
to claim exclusive control over the rate of a producer
So far, rate change operations have been a "last write wins" affair. This
changes allows drivers to explicitly protect against this behavior, if
required.
Of course, if exclusivity over a producer is claimed more than once, the
rate is effectively locked as exclusivity cannot be preempted
Tested-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Link: lkml.kernel.org/r/20171201215200.23523-10-jbrunet@baylibre.com
The patch adds clk_core_protect and clk_core_unprotect to the internal
CCF API. These functions allow to set a new constraint along the clock
tree to prevent any change, even indirect, which may result in rate
change or glitch.
Tested-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Link: lkml.kernel.org/r/20171201215200.23523-7-jbrunet@baylibre.com
Stephen Boyd
Matti Vaittinen
Keerthy
Russ Dill
Linus Torvalds
Mark Brown
Mikko Perttunen
Geert Uytterhoeven
Jerome Brunet
Mauro Carvalho Chehab
Yisheng Xie
Greg Kroah-Hartman
Shawn Lin
Andy Shevchenko
Fabio Estevam
Stephen Boyd
David Lechner
Dong Aisheng