voppwm is frame effect, so we need add vop pwm en to
indicate the pwm en state.
Change-Id: I1492322f99b638c8dc6cf03c87035f28dca3de8f
Signed-off-by: Sandy Huang <hjc@rock-chips.com>
The rk3328 SoC supports atomic update, we could lock the configuration
of period and duty at first, after unlock is configured, the period and
duty are effective at the same time.
If the polarity, period and duty need to be configured together,
the way for atomic update is "configure lock and old polarity" ->
"configure period and duty" -> "configure unlock and new polarity".
Change-Id: I93d47566673ab6338d1f7e18212318b8f5277383
Signed-off-by: David Wu <david.wu@rock-chips.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Just use the same PWM ops for each IP, and get rid of the ops in struct
rockchip_pwm_data, but still define the three different instances of the
struct to use common interface for each IP.
Change-Id: I8a449b9b5d26be2d0ad85ed0013bf5b764f41a83
Signed-off-by: David Wu <david.wu@rock-chips.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
It is usually possible to configure the polarity, cycle and duty all at
once, so that the polarity and cycle and duty are applied atomically.
Move it from rockchip_pwm_set_enable() into rockchip_pwm_config(), as
well as prepare for the next atomic update commit.
Change-Id: I051ce87facc892353ee2f061fcc9148085f0f21b
Signed-off-by: David Wu <david.wu@rock-chips.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Drop the custom hook of pwm_enable() and implement pwm_apply_v1() and
pwm_apply_v2() instead.
Change-Id: I34c6a1206f4ae53ca48756981a2c07b4ec0e7be4
Signed-off-by: David Wu <david.wu@rock-chips.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
New PWM module provides two individual clocks for APB clock and function
clock.
Signed-off-by: David Wu <david.wu@rock-chips.com>
Change-Id: I9f32de5734f9e66472ae5350023ffce9548d717d
LSK 17.03 v4.4-android
* tag 'lsk-v4.4-17.03-android': (166 commits)
Linux 4.4.55
ext4: don't BUG when truncating encrypted inodes on the orphan list
dm: flush queued bios when process blocks to avoid deadlock
nfit, libnvdimm: fix interleave set cookie calculation
s390/kdump: Use "LINUX" ELF note name instead of "CORE"
KVM: s390: Fix guest migration for huge guests resulting in panic
mvsas: fix misleading indentation
serial: samsung: Continue to work if DMA request fails
USB: serial: io_ti: fix information leak in completion handler
USB: serial: io_ti: fix NULL-deref in interrupt callback
USB: iowarrior: fix NULL-deref in write
USB: iowarrior: fix NULL-deref at probe
USB: serial: omninet: fix reference leaks at open
USB: serial: safe_serial: fix information leak in completion handler
usb: host: xhci-plat: Fix timeout on removal of hot pluggable xhci controllers
usb: host: xhci-dbg: HCIVERSION should be a binary number
usb: gadget: function: f_fs: pass companion descriptor along
usb: dwc3: gadget: make Set Endpoint Configuration macros safe
usb: gadget: dummy_hcd: clear usb_gadget region before registration
powerpc: Emulation support for load/store instructions on LE
...
Change-Id: I4db95bbe5b2523e19ddf22b3f65863f7f6d46632
commit 8d254a340e upstream.
When first implementing support for changing the output frequency, an
optimization was added to continue the PWM after changing the prescaler
without having to reprogram the ON and OFF registers for the duty cycle,
in case the duty cycle stayed the same. This was flawed, because we
compared the absolute value of the duty cycle in nanoseconds instead of
the ratio to the period.
Fix the problem by removing the shortcut.
Fixes: 01ec847200 ("pwm-pca9685: Support changing the output frequency")
Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use pwm_get/set_xxx() helpers instead of directly accessing the pwm->xxx
field. Doing that will ease adaptation of the PWM framework to support
atomic update.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 4b58896f72)
Change-Id: Ic6bdaf2017bb292ef920604fba86805999cebf0c
Signed-off-by: Huang, Tao <huangtao@rock-chips.com>
This patch fix the following warning:
drivers/pwm/pwm-rockchip.c:176:6: warning: unused variable 'ret' [-Wunused-variable]
Change-Id: I9ac08ad08fdefee5b875d36592936b07f032586c
Signed-off-by: David Wu <david.wu@rock-chips.com>
If the pwm was not enabled at uboot loader, pwm could not work for clock
always disabled at pwm driver. The pwm clock is enabled at beginning of
pwm_apply(), but disabled at end of pwm_apply().
If the pwm was enabled at uboot loader, pwm clock is always enabled unless
closed by ATF. The pwm-backlight might turn off the power at early suspend,
should disable pwm clock for saving power consume.
It is important to provide opportunity to enable/disable clock at pwm driver,
the pwm consumer should ensure correct order to call pwm enable/disable, and
pwm driver ensure state of pwm clock synchronized with pwm enabled state.
Change-Id: I545db81eb638957567abacb93fd06fff9dd7181b
Fixes: 2bf1c98aa5 ("pwm: rockchip: Add support for atomic update")
Signed-off-by: David Wu <david.wu@rock-chips.com>
While the particular usage in question is likely safe (struct
cros_ec_command is 32-bit aligned, followed by <= 32-bit fields), it's
been suggested this is not a great pattern to follow for the general
case -- for example, if we follow a 'struct cros_ec_command' (which is
32-bit- but not 64-bit-aligned) with a struct that starts with a 64-bit
type (e.g., u64), the compiler may add padding.
Let's add __packed, to inform the compiler of our true intention -- to
have no padding between these struct elements -- and to future proof for
any refactorings that might occur.
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 065cfbbb63)
Change-Id: Iddd499863dde168679a88c2f9ecc461316b417a0
Signed-off-by: David Wu <david.wu@rock-chips.com>
Use the new ChromeOS EC EC_CMD_PWM_{GET,SET}_DUTY commands to control
one or more PWMs attached to the Embedded Controller. Because the EC
allows us to modify the duty cycle (as a percentage, where U16_MAX is
100%) but not the period, we assign the period a fixed value of
EC_PWM_MAX_DUTY and reject all attempts to change it.
This driver supports only device tree at the moment, because that
provides a very flexible way of describing the relationship between PWMs
and their consumer devices (e.g., backlight). On a non-DT system, we'll
probably want to use the non-GENERIC addressing (i.e., we'll need to
make special device instances that will use EC_PWM_TYPE_KB_LIGHT or
EC_PWM_TYPE_DISPLAY_LIGHT), as well as the relatively inflexible
pwm_lookup infrastructure for matching devices. Defer that work for now.
Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 1f0d3bb027)
Change-Id: I47dbb20b10ae1b941e50e9a783cb708dff8f7efd
Signed-off-by: David Wu <david.wu@rock-chips.com>
The current logic will disable the PWM clk even if the PWM was left
enabled by the bootloader (because it's controlling a critical device
like a regulator for example).
Keep the PWM clk enabled if the PWM is enabled to avoid any glitches.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Tested-by: Brian Norris <briannorris@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(commit 48cf973cae)
Conflicts:
drivers/pwm/pwm-rockchip.c
Change-Id: I75ffccd19c5244568fc0034d1585dac490296111
Signed-off-by: David Wu <david.wu@rock-chips.com>
The current implementation always round down the duty and period values,
while it would be better to round them to the closest integer.
These changes are needed in preparation of atomic update support to
prevent a period/duty cycle drift when executing several times the
'pwm_get_state() / modify / pwm_apply_state()' sequence.
Say you have an expected period of 3.333 us and a clk rate of
112.666667 MHz -- the clock frequency doesn't divide evenly, so the
period (stashed in nanoseconds) shrinks when we convert to the register
value and back, as follows:
pwm_apply_state(): register = period * 112666667 / 1000000000;
pwm_get_state(): period = register * 1000000000 / 112666667;
or in other words:
period = period * 112666667 / 1000000000 * 1000000000 / 112666667;
which yields a sequence like:
3333 -> 3328
3328 -> 3319
3319 -> 3310
3310 -> 3301
3301 -> 3292
3292 -> ... (etc) ...
With this patch, we'd see instead:
period = div_round_closest(period * 112666667, 1000000000) *
1000000000 / 112666667;
which yields a stable sequence:
3333 -> 3337
3337 -> 3337
3337 -> ... (etc) ...
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Tested-by: Brian Norris <briannorris@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 12f9ce4a51)
Change-Id: Ife75404e663d1380725d634ac621b2ca9f831791
Signed-off-by: David Wu <david.wu@rock-chips.com>
Allow a user to read PWM capture results from sysfs. To start a capture
and read the result, simply read the file:
$ cat $PWMCHIP/capture
The output format is "<period> <duty cycle>".
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 1a366fe915)
Change-Id: I86326709c373630a9189232a1cf2804a1a6ed380
Signed-off-by: David Wu <david.wu@rock-chips.com>
Supply a PWM capture callback op in order to pass back information
obtained by running analysis on a PWM signal. This would normally (at
least during testing) be called from the sysfs routines with a view to
printing out PWM capture data which has been encoded into a string.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
[thierry.reding@gmail.com: make capture data unsigned int for symmetry]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 3a3d1a4e32)
Change-Id: Iee3acf2eb02c5282d586f4e7f1745031e17cc383
Signed-off-by: David Wu <david.wu@rock-chips.com>
This patch adds to check the return value from pwm_apply_state()
used in enable_store(). The error of enable_store() doesn't work
if the return value doesn't received.
Signed-off-by: Ryo Kodama <ryo.kodama.vz@renesas.com>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Fixes: 39100ceea7 ("pwm: Switch to the atomic API")
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit fe5aa34d6e)
Change-Id: I550da28345bcee7a6aa8e1f9b5c43adae923ff2d
Signed-off-by: David Wu <david.wu@rock-chips.com>
It seems like in the process of refactoring pwm_config() to utilize the
newly-introduced pwm_apply_state() API, some args/bounds checking was
dropped.
In particular, I noted that we are now allowing invalid period
selections, e.g.:
# echo 1 > /sys/class/pwm/pwmchip0/export
# cat /sys/class/pwm/pwmchip0/pwm1/period
100
# echo 101 > /sys/class/pwm/pwmchip0/pwm1/duty_cycle
[... driver may or may not reject the value, or trigger some logic bug ...]
It's better to see:
# echo 1 > /sys/class/pwm/pwmchip0/export
# cat /sys/class/pwm/pwmchip0/pwm1/period
100
# echo 101 > /sys/class/pwm/pwmchip0/pwm1/duty_cycle
-bash: echo: write error: Invalid argument
This patch reintroduces some bounds checks in both pwm_config() (for its
signed parameters; we don't want to convert negative values into large
unsigned values) and in pwm_apply_state() (which fix the above described
behavior, as well as other potential API misuses).
Fixes: 5ec803edcb ("pwm: Add core infrastructure to allow atomic updates")
Signed-off-by: Brian Norris <briannorris@chromium.org>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit ef2bf4997f)
Change-Id: I7d7515a51b5c3c2a77ae9743b7ed69eedc11d4b4
Signed-off-by: David Wu <david.wu@rock-chips.com>
The PWM states make it possible to also output the polarity, duty cycle
and period information in the debugfs summary output. This simplifies
gathering information about PWMs without needing to walk through the
sysfs attributes of every PWM.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
[thierry.reding@gmail.com: use more spaces in debugfs output]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 23e3523f5d)
Change-Id: Ia5d4d9ab898510d07364ad455ccf93e1c1d95d2b
Signed-off-by: David Wu <david.wu@rock-chips.com>
Add an ->apply() method to the pwm_ops struct to allow PWM drivers to
implement atomic updates. This method is preferred over the ->enable(),
->disable() and ->config() methods if available.
Add the pwm_apply_state() function to the PWM user API.
Note that the pwm_apply_state() does not guarantee the atomicity of the
update operation, it all depends on the availability and implementation
of the ->apply() method.
pwm_enable/disable/set_polarity/config() are now implemented as wrappers
around the pwm_apply_state() function.
pwm_adjust_config() is allowing smooth handover between the bootloader
and the kernel. This function tries to adapt the current PWM state to
the PWM arguments coming from a PWM lookup table or a DT definition
without changing the duty_cycle/period proportion.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
[thierry.reding@gmail.com: fix a couple of typos]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 5ec803edcb)
Change-Id: Ib527f34ca3ce90ded3b48725d7ab9509de2053c9
Signed-off-by: David Wu <david.wu@rock-chips.com>
Add a ->get_state() function to the pwm_ops struct to let PWM drivers
initialize the PWM state attached to a PWM device.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 15fa8a43c1)
Change-Id: Ie37be2d34833cbb6cc4b4b4cb6af98ac721b953a
Signed-off-by: David Wu <david.wu@rock-chips.com>
Prepare the transition to PWM atomic update by moving the enabled and
disabled state into the pwm_state struct. This way we can easily update
the whole PWM state by copying the new state in the ->state field.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 09a7e4a3d9)
Change-Id: I38808d868c7e73f0ffd49cfb6c0b4b45fa911613
Signed-off-by: David Wu <david.wu@rock-chips.com>
The PWM state, represented by its period, duty_cycle and polarity is
currently directly stored in the PWM device. Declare a pwm_state
structure embedding those field so that we can later use this struct
to atomically update all the PWM parameters at once.
All pwm_get_xxx() helpers are now implemented as wrappers around
pwm_get_state().
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 43a276b003)
Change-Id: I44037440bcc9d9164d18f3bfa1c8ff3e593925c5
Signed-off-by: David Wu <david.wu@rock-chips.com>
Before the introduction of pwm_args, the core was resetting the PWM
period and polarity states to the reference values (those provided
through the DT, a PWM lookup table or hardcoded in the driver).
Now that all PWM users are correctly using pwm_args to configure their
PWM device, we can safely remove the pwm_apply_args() call in pwm_get()
and of_pwm_get().
We can also get rid of the pwm_set_period() call in pwm_apply_args(),
because PWM users are now directly using pargs->period instead of
pwm_get_period(). By doing that we avoid messing with the current PWM
period.
The only remaining bit in pwm_apply_args() is the initial polarity
setting, and it should go away when all PWM users have been patched to
use the atomic API (with this API the polarity will be set along with
other PWM arguments when configuring the PWM).
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit a8c3862551)
Change-Id: I5112f2d8a7b66e01184984376dcae84decf5ad28
Signed-off-by: David Wu <david.wu@rock-chips.com>
PWM devices are not protected against concurrent accesses. The lock in
struct pwm_device might let PWM users think it is, but it's actually
only protecting the enabled state.
Removing this lock should be fine as long as all PWM users are aware
that accesses to the PWM device have to be serialized, which seems to be
the case for all of them except the sysfs interface. Patch the sysfs
code by adding a lock to the pwm_export struct and making sure it's
taken for all relevant accesses to the exported PWM device.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 459a25afe9)
Change-Id: I30d97ebaf1db8b80c353da5ebebd0fc5d5c57bb0
Signed-off-by: David Wu <david.wu@rock-chips.com>
pwm_apply_args() is supposed to initialize a PWM device according to the
arguments provided by the DT or the PWM lookup, but this function was
called inside pwm_device_request(), which in turn was called before the
core had a chance to initialize the pwm->args fields.
Fix that by calling pwm_apply_args directly in pwm_get() and of_pwm_get()
after initializing pwm->args field.
This commit also fixes an invalid pointer dereference introduced by
commit e39c0df1be ("pwm: Introduce the pwm_args concept").
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Fixes: e39c0df1be ("pwm: Introduce the pwm_args concept")
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit fbd45a1298)
Change-Id: I9746f4ada57a6cc8155bafe662a63c82338c223a
Signed-off-by: David Wu <david.wu@rock-chips.com>
kcalloc() should be preferred for allocations of arrays over kzalloc()
with multiplication.
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 2907f8abb7)
Change-Id: Ifa4619bcd5c0869e516ae7765bab7515b299c533
Signed-off-by: David Wu <david.wu@rock-chips.com>
checkpatch requires that declarations be separated from code by a blank
line. Add one for readability and to silence the warning.
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 83a98864ff)
Change-Id: I1e59599b099fe6b4d29e0f39225f8e18ce7c139e
Signed-off-by: David Wu <david.wu@rock-chips.com>
Currently the PWM core mixes the current PWM state with the per-platform
reference config (specified through the PWM lookup table, DT definition
or directly hardcoded in PWM drivers).
Create a struct pwm_args to store this reference configuration, so that
PWM users can differentiate between the current and reference
configurations.
Patch all places where pwm->args should be initialized. We keep the
pwm_set_polarity/period() calls until all PWM users are patched to use
pwm_args instead of pwm_get_period/polarity().
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
[thierry.reding@gmail.com: reword kerneldoc comments]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit e39c0df1be)
Change-Id: Id9ec0898d92d7049813c32acbd909103e949c846
Signed-off-by: David Wu <david.wu@rock-chips.com>
New PWM module provides two individual clocks for APB bus clock
and function clock.
Change-Id: I0c262472c5d8b0c527c5a0a8d66b4512ac66f2ce
Signed-off-by: david.wu <david.wu@rock-chips.com>
* linux-linaro-lsk-v4.4-android: (199 commits)
Linux 4.4.41
net: mvpp2: fix dma unmapping of TX buffers for fragments
sg_write()/bsg_write() is not fit to be called under KERNEL_DS
kconfig/nconf: Fix hang when editing symbol with a long prompt
target/user: Fix use-after-free of tcmu_cmds if they are expired
powerpc: Convert cmp to cmpd in idle enter sequence
powerpc/ps3: Fix system hang with GCC 5 builds
nfs_write_end(): fix handling of short copies
libceph: verify authorize reply on connect
PCI: Check for PME in targeted sleep state
Input: drv260x - fix input device's parent assignment
media: solo6x10: fix lockup by avoiding delayed register write
IB/cma: Fix a race condition in iboe_addr_get_sgid()
IB/multicast: Check ib_find_pkey() return value
IPoIB: Avoid reading an uninitialized member variable
IB/mad: Fix an array index check
fgraph: Handle a case where a tracer ignores set_graph_notrace
platform/x86: asus-nb-wmi.c: Add X45U quirk
ftrace/x86_32: Set ftrace_stub to weak to prevent gcc from using short jumps to it
kvm: nVMX: Allow L1 to intercept software exceptions (#BP and #OF)
...
Change-Id: I8c8467700d5563d9a1121c982737ff0ab6d9cdc9
commit 0e1614ac84 upstream.
Make sure to drop the reference to the parent device taken by
class_find_device() after "unexporting" any children when deregistering
a PWM chip.
Fixes: 0733424c9b ("pwm: Unexport children before chip removal")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0733424c9b upstream.
Exported pwm channels aren't removed before the pwmchip and are
leaked. This results in invalid sysfs files. This fix removes
all exported pwm channels before chip removal.
Signed-off-by: David Hsu <davidhsu@google.com>
Fixes: 76abbdde2d ("pwm: Add sysfs interface")
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* linux-linaro-lsk-v4.4-android: (1362 commits)
Linux 4.4.30
Revert "fix minor infoleak in get_user_ex()"
Revert "x86/mm: Expand the exception table logic to allow new handling options"
Linux 4.4.29
ARM: pxa: pxa_cplds: fix interrupt handling
powerpc/nvram: Fix an incorrect partition merge
mpt3sas: Don't spam logs if logging level is 0
perf symbols: Fixup symbol sizes before picking best ones
perf symbols: Check symbol_conf.allow_aliases for kallsyms loading too
perf hists browser: Fix event group display
clk: divider: Fix clk_divider_round_rate() to use clk_readl()
clk: qoriq: fix a register offset error
s390/con3270: fix insufficient space padding
s390/con3270: fix use of uninitialised data
s390/cio: fix accidental interrupt enabling during resume
x86/mm: Expand the exception table logic to allow new handling options
dmaengine: ipu: remove bogus NO_IRQ reference
power: bq24257: Fix use of uninitialized pointer bq->charger
staging: r8188eu: Fix scheduling while atomic splat
ASoC: dapm: Fix kcontrol creation for output driver widget
...
commit ff01c944cf upstream.
Commit d1cd214277 ("pwm: Set enable state properly on failed call to
enable") introduced a mutex that is needed to protect internal state of
PWM devices. Since that mutex is acquired in pwm_set_polarity() and in
pwm_enable() and might potentially block, all PWM devices effectively
become "might sleep".
It's rather pointless to keep the .can_sleep field around, but given
that there are external users let's postpone the removal for the next
release cycle.
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: d1cd214277 ("pwm: Set enable state properly on failed call to enable")
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
[ Upstream commit 5a9fc9c666 ]
The change fixes a problem, if duty_ns is too small in comparison
to period_ns (as a valid corner case duty_ns is 0 ns), then due to
PWM_DUTY() macro applied on a value the result is overflowed over 8
bits, and instead of the highest bitfield duty cycle value 0xff the
invalid duty cycle bitfield value 0x00 is written.
For reference the LPC32xx spec defines PWMx_DUTY bitfield description
is this way and it seems to be correct:
[Low]/[High] = [PWM_DUTY]/[256-PWM_DUTY], where 0 < PWM_DUTY <= 255.
In addition according to my oscilloscope measurements LPC32xx PWM is
"tristate" in sense that it produces a wave with floating min/max
voltage levels for different duty cycle values, for corner cases:
PWM_DUTY == 0x01 => signal is in range from -1.05v to 0v
....
PWM_DUTY == 0x80 => signal is in range from -0.75v to +0.75v
....
PWM_DUTY == 0xff => signal is in range from 0v to +1.05v
PWM_DUTY == 0x00 => signal is around 0v, PWM is off
Due to this peculiarity on very long period ranges (less than 1KHz)
and odd pre-divider values PWM generated wave does not remind a
clock shape signal, but rather a heartbit shape signal with positive
and negative peaks, so I would recommend to use high-speed HCLK clock
as a PWM parent clock and avoid using RTC clock as a parent.
The change corrects PWM output in corner cases and prevents any
possible overflows in calculation of values for PWM_DUTY and
PWM_RELOADV bitfields, thus helper macro definitions may be removed.
Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit ebe1fca350 ]
LPC32xx SoC has two independent PWM controllers, they have different
clock parents, clock gates and even slightly different controls, and
each of these two PWM controllers has one output channel. Due to
almost similar controls arranged in a row it is incorrectly set that
there is one PWM controller with two channels, fix this problem, which
at the moment prevents separate configuration of different clock
parents and gates for both PWM controllers.
The change makes previous PWM device node description incompatible
with this update.
Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 816aec2325 ]
A FTM PWM instance enables/disables three clocks: The bus clock, the
counter clock and the PWM clock. The bus clock gets enabled on
pwm_request, whereas the counter and PWM clocks will be enabled upon
pwm_enable.
The driver has three closesly related issues when enabling/disabling
clocks during suspend/resume:
- The three clocks are not treated differently in regards to the
individual PWM state enabled/requested. This can lead to clocks
getting disabled which have not been enabled in the first place
(a PWM channel which only has been requested going through
suspend/resume).
- When entering suspend, the current behavior relies on the
FTM_OUTMASK register: If a PWM output is unmasked, the driver
assumes the clocks are enabled. However, some PWM instances
have only 2 channels connected (e.g. Vybrid's FTM1). In that case,
the FTM_OUTMASK reads 0x3 if all channels are disabled, even if
the code wrote 0xff to it before. For those PWM instances, the
current approach to detect enabled PWM signals does not work.
- A third issue applies to the bus clock only, which can get enabled
multiple times (once for each PWM channel of a PWM chip). This is
fine, however when entering suspend mode, the clock only gets
disabled once.
This change introduces a different approach by relying on the enable
and prepared counters of the clock framework and using the frameworks
PWM signal states to address all three issues.
Clocks get disabled during suspend and back enabled on resume
regarding to the PWM channels individual state (requested/enabled).
Since we do not count the clock enables in the driver, this change no
longer clears the Status and Control registers Clock Source Selection
(FTM_SC[CLKS]). However, since we disable the selected clock anyway,
and we explicitly select the clock source on reenabling a PWM channel
this approach should not make a difference in practice.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If pwm polarity was configured with different values at uboot,
the enable_conf would not be configured correctly.
Change-Id: I55b9ccc262382951a8a82810f1be74ce9460f266
Signed-off-by: Zhou weixin <zwx@rock-chips.com>
* linux-linaro-lsk-v4.4-android: (797 commits)
parisc: Use generic extable search and sort routines
arm64: kasan: Use actual memory node when populating the kernel image shadow
arm64: mm: treat memstart_addr as a signed quantity
arm64: lse: deal with clobbered IP registers after branch via PLT
arm64: mm: check at build time that PAGE_OFFSET divides the VA space evenly
arm64: kasan: Fix zero shadow mapping overriding kernel image shadow
arm64: consistently use p?d_set_huge
arm64: fix KASLR boot-time I-cache maintenance
arm64: hugetlb: partial revert of 66b3923a1a
arm64: make irq_stack_ptr more robust
arm64: efi: invoke EFI_RNG_PROTOCOL to supply KASLR randomness
efi: stub: use high allocation for converted command line
efi: stub: add implementation of efi_random_alloc()
efi: stub: implement efi_get_random_bytes() based on EFI_RNG_PROTOCOL
arm64: kaslr: randomize the linear region
arm64: add support for kernel ASLR
arm64: add support for building vmlinux as a relocatable PIE binary
arm64: switch to relative exception tables
extable: add support for relative extables to search and sort routines
scripts/sortextable: add support for ET_DYN binaries
...
Conflicts:
arch/arm64/mm/dma-mapping.c
drivers/clk/rockchip/clk-rk3368.c
drivers/mmc/core/core.c
drivers/mmc/core/sdio.c
include/linux/dcache.h
Change-Id: Ibaa1e90ac735db8d9f5e542c266ef27b91616ef4
