Commit graph

744 commits

Author SHA1 Message Date
Uwe Kleine-König
c37a34d797 pwm: stm32-lp: Don't modify HW state in .remove() callback
[ Upstream commit d44084c934 ]

A consumer is expected to disable a PWM before calling pwm_put(). And if
they didn't there is hopefully a good reason (or the consumer needs
fixing). Also if disabling an enabled PWM was the right thing to do,
this should better be done in the framework instead of in each low level
driver.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-26 14:07:13 +02:00
Uwe Kleine-König
8a29e68ea8 pwm: rockchip: Don't modify HW state in .remove() callback
[ Upstream commit 9d768cd7fd ]

A consumer is expected to disable a PWM before calling pwm_put(). And if
they didn't there is hopefully a good reason (or the consumer needs
fixing). Also if disabling an enabled PWM was the right thing to do,
this should better be done in the framework instead of in each low level
driver.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-26 14:07:13 +02:00
Uwe Kleine-König
ed60d2db31 pwm: img: Don't modify HW state in .remove() callback
[ Upstream commit c68eb29c8e ]

A consumer is expected to disable a PWM before calling pwm_put(). And if
they didn't there is hopefully a good reason (or the consumer needs
fixing). Also if disabling an enabled PWM was the right thing to do,
this should better be done in the framework instead of in each low level
driver.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-26 14:07:13 +02:00
Uwe Kleine-König
81e6b51709 pwm: lpc32xx: Don't modify HW state in .probe() after the PWM chip was registered
commit 3d2813fb17 upstream.

This fixes a race condition: After pwmchip_add() is called there might
already be a consumer and then modifying the hardware behind the
consumer's back is bad. So set the default before.

(Side-note: I don't know what this register setting actually does, if
this modifies the polarity there is an inconsistency because the
inversed polarity isn't considered if the PWM is already running during
.probe().)

Fixes: acfd92fdfb ("pwm: lpc32xx: Set PWM_PIN_LEVEL bit to default value")
Cc: Sylvain Lemieux <slemieux@tycoint.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-26 14:07:09 +02:00
Uwe Kleine-König
ae9b644344 pwm: sprd: Ensure configuring period and duty_cycle isn't wrongly skipped
[ Upstream commit 65e2e6c1c2 ]

As the last call to sprd_pwm_apply() might have exited early if
state->enabled was false, the values for period and duty_cycle stored in
pwm->state might not have been written to hardware and it must be
ensured that they are configured before enabling the PWM.

Fixes: 8aae4b02e8 ("pwm: sprd: Add Spreadtrum PWM support")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-28 13:30:53 +02:00
Uwe Kleine-König
aac6a79ee0 pwm: imx1: Don't disable clocks at device remove time
[ Upstream commit 1bc6ea31cb ]

The .remove() callback disables clocks that were not enabled in
.probe(). So just probing and then unbinding the driver results in a clk
enable imbalance.

So just drop the call to disable the clocks. (Which BTW was also in the
wrong order because the call makes the PWM unfunctional and so should
have come only after pwmchip_remove()).

Fixes: 9f4c8f9607 ("pwm: imx: Add ipg clock operation")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-20 16:10:50 +02:00
Uwe Kleine-König
7d06675215 pwm: tegra: Don't modify HW state in .remove callback
[ Upstream commit 86f7fa71cd ]

A consumer is expected to disable a PWM before calling pwm_put(). And if
they didn't there is hopefully a good reason (or the consumer needs
fixing). Also if disabling an enabled PWM was the right thing to do,
this should better be done in the framework instead of in each low level
driver.

So drop the hardware modification from the .remove() callback.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-20 16:10:48 +02:00
Zou Wei
f8ba40611b pwm: img: Fix PM reference leak in img_pwm_enable()
[ Upstream commit fde25294df ]

pm_runtime_get_sync will increment pm usage counter even it failed.
Forgetting to putting operation will result in reference leak here.
Fix it by replacing it with pm_runtime_resume_and_get to keep usage
counter balanced.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-20 16:10:48 +02:00
Uwe Kleine-König
af619a7455 pwm: spear: Don't modify HW state in .remove callback
[ Upstream commit b601a18f12 ]

A consumer is expected to disable a PWM before calling pwm_put(). And if
they didn't there is hopefully a good reason (or the consumer needs
fixing). Also if disabling an enabled PWM was the right thing to do,
this should better be done in the framework instead of in each low level
driver.

So drop the hardware modification from the .remove() callback.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-20 16:10:46 +02:00
Simon South
e8ba750116 pwm: rockchip: rockchip_pwm_probe(): Remove superfluous clk_unprepare()
[ Upstream commit d5d8d67586 ]

If rockchip_pwm_probe() fails to register a PWM device it calls
clk_unprepare() for the device's PWM clock, without having first disabled
the clock and before jumping to an error handler that also unprepares
it. This is likely to produce warnings from the kernel about the clock
being unprepared when it is still enabled, and then being unprepared when
it has already been unprepared.

Prevent these warnings by removing this unnecessary call to
clk_unprepare().

Fixes: 48cf973cae ("pwm: rockchip: Avoid glitches on already running PWMs")
Signed-off-by: Simon South <simon@simonsouth.net>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04 10:26:36 +01:00
Lokesh Vutla
ceadde18f6 pwm: lp3943: Dynamically allocate PWM chip base
[ Upstream commit 1f0f1e80fd ]

When there are other PWM controllers enabled along with pwm-lp3943,
pwm-lp3942 is failing to probe with -EEXIST error. This is because
other PWM controllers are probed first and assigned PWM base 0 and
pwm-lp3943 is requesting for 0 again.

In order to avoid this, assign the chip base with -1, so that it is
dynamically allocated.

Fixes: af66b3c093 ("pwm: Add LP3943 PWM driver")
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Uwe Kleine-König <u.kleine-könig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:51:28 +01:00
Uwe Kleine-König
6bf2ef4bd3 pwm: zx: Add missing cleanup in error path
[ Upstream commit 269effd03f ]

zx_pwm_probe() called clk_prepare_enable() before; this must be undone
in the error path.

Fixes: 4836193c43 ("pwm: Add ZTE ZX PWM device driver")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:51:28 +01:00
Hauke Mehrtens
72407e5aa0 pwm: img: Fix null pointer access in probe
[ Upstream commit b39c0615d0 ]

dev_get_drvdata() is called in img_pwm_runtime_resume() before the
driver data is set.
When pm_runtime_enabled() returns false in img_pwm_probe() it calls
img_pwm_runtime_resume() which results in a null pointer access.

This patch fixes the problem by setting the driver data earlier in the
img_pwm_probe() function.

This crash was seen when booting the Imagination Technologies Creator
Ci40 (Marduk) with kernel 5.4 in OpenWrt.

Fixes: e690ae5262 ("pwm: img: Add runtime PM")
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-29 09:57:54 +01:00
Hans de Goede
bf12e769ff pwm: lpss: Add range limit check for the base_unit register value
[ Upstream commit ef9f60daab ]

When the user requests a high enough period ns value, then the
calculations in pwm_lpss_prepare() might result in a base_unit value of 0.

But according to the data-sheet the way the PWM controller works is that
each input clock-cycle the base_unit gets added to a N bit counter and
that counter overflowing determines the PWM output frequency. Adding 0
to the counter is a no-op. The data-sheet even explicitly states that
writing 0 to the base_unit bits will result in the PWM outputting a
continuous 0 signal.

When the user requestes a low enough period ns value, then the
calculations in pwm_lpss_prepare() might result in a base_unit value
which is bigger then base_unit_range - 1. Currently the codes for this
deals with this by applying a mask:

	base_unit &= (base_unit_range - 1);

But this means that we let the value overflow the range, we throw away the
higher bits and store whatever value is left in the lower bits into the
register leading to a random output frequency, rather then clamping the
output frequency to the highest frequency which the hardware can do.

This commit fixes both issues by clamping the base_unit value to be
between 1 and (base_unit_range - 1).

Fixes: 684309e504 ("pwm: lpss: Avoid potential overflow of base_unit")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200903112337.4113-5-hdegoede@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-29 09:57:38 +01:00
Hans de Goede
34f326e702 pwm: lpss: Fix off by one error in base_unit math in pwm_lpss_prepare()
[ Upstream commit 181f4d2f44 ]

According to the data-sheet the way the PWM controller works is that
each input clock-cycle the base_unit gets added to a N bit counter and
that counter overflowing determines the PWM output frequency.

So assuming e.g. a 16 bit counter this means that if base_unit is set to 1,
after 65535 input clock-cycles the counter has been increased from 0 to
65535 and it will overflow on the next cycle, so it will overflow after
every 65536 clock cycles and thus the calculations done in
pwm_lpss_prepare() should use 65536 and not 65535.

This commit fixes this. Note this also aligns the calculations in
pwm_lpss_prepare() with those in pwm_lpss_get_state().

Note this effectively reverts commit 684309e504 ("pwm: lpss: Avoid
potential overflow of base_unit"). The next patch in this series really
fixes the potential overflow of the base_unit value.

Fixes: 684309e504 ("pwm: lpss: Avoid potential overflow of base_unit")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200903112337.4113-4-hdegoede@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-29 09:57:38 +01:00
Rayagonda Kokatanur
3d0808f3c7 pwm: bcm-iproc: handle clk_get_rate() return
[ Upstream commit 6ced5ff0be ]

Handle clk_get_rate() returning 0 to avoid possible division by zero.

Fixes: daa5abc41c ("pwm: Add support for Broadcom iProc PWM controller")
Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21 13:05:34 +02:00
Uwe Kleine-König
d64dc6118a pwm: jz4740: Fix build failure
When commit 9017dc4fbd ("pwm: jz4740: Enhance precision in calculation
of duty cycle") from v5.8-rc1 was backported to v5.4.x its dependency on
commit ce1f9cece0 ("pwm: jz4740: Use clocks from TCU driver") was not
noticed which made the pwm-jz4740 driver fail to build.

As ce1f9cece0 depends on still more rework, just backport a small part
of this commit to make the driver build again. (There is no dependency
on the functionality introduced in ce1f9cece0, just the rate variable
is needed.)

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reported-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-16 08:16:48 +02:00
Paul Cercueil
a6030d71e6 pwm: jz4740: Enhance precision in calculation of duty cycle
commit 9017dc4fbd upstream.

Calculating the hardware value for the duty from the hardware value of
the period resulted in a precision loss versus calculating it from the
clock rate directly.

(Also remove a cast that doesn't really need to be here)

Fixes: f6b8a57000 ("pwm: Add Ingenic JZ4740 support")
Cc: <stable@vger.kernel.org>
Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
[ukl: backport to v5.4.y and adapt commit log accordingly]
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24 17:50:52 +02:00
Navid Emamdoost
7f16ba366a pwm: img: Call pm_runtime_put() in pm_runtime_get_sync() failed case
[ Upstream commit ca162ce981 ]

Even in failed case of pm_runtime_get_sync(), the usage_count is
incremented. In order to keep the usage_count with correct value call
appropriate pm_runtime_put().

Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-24 17:50:18 +02:00
Florian Fainelli
41a3e446bc pwm: bcm2835: Dynamically allocate base
[ Upstream commit 2c25b07e5e ]

The newer 2711 and 7211 chips have two PWM controllers and failure to
dynamically allocate the PWM base would prevent the second PWM
controller instance being probed for succeeding with an -EEXIST error
from alloc_pwms().

Fixes: e5a06dc5ac ("pwm: Add BCM2835 PWM driver")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-29 16:33:02 +02:00
Geert Uytterhoeven
53cdc935c9 pwm: renesas-tpu: Fix late Runtime PM enablement
[ Upstream commit d5a3c7a453 ]

Runtime PM should be enabled before calling pwmchip_add(), as PWM users
can appear immediately after the PWM chip has been added.
Likewise, Runtime PM should always be disabled after the removal of the
PWM chip, even if the latter failed.

Fixes: 99b82abb0a ("pwm: Add Renesas TPU PWM driver")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-29 16:33:02 +02:00
Geert Uytterhoeven
a5f036adae pwm: rcar: Fix late Runtime PM enablement
[ Upstream commit 1451a3eed2 ]

Runtime PM should be enabled before calling pwmchip_add(), as PWM users
can appear immediately after the PWM chip has been added.
Likewise, Runtime PM should be disabled after the removal of the PWM
chip.

Fixes: ed6c1476bf ("pwm: Add support for R-Car PWM Timer")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-29 16:32:58 +02:00
Sven Van Asbroeck
229563dc6b pwm: pca9685: Fix PWM/GPIO inter-operation
commit 9cc5f232a4 upstream.

This driver allows pwms to be requested as gpios via gpiolib. Obviously,
it should not be allowed to request a GPIO when its corresponding PWM is
already requested (and vice versa). So it requires some exclusion code.

Given that the PWMm and GPIO cores are not synchronized with respect to
each other, this exclusion code will also require proper
synchronization.

Such a mechanism was in place, but was inadvertently removed by Uwe's
clean-up in commit e926b12c61 ("pwm: Clear chip_data in pwm_put()").

Upon revisiting the synchronization mechanism, we found that
theoretically, it could allow two threads to successfully request
conflicting PWMs/GPIOs.

Replace with a bitmap which tracks PWMs in-use, plus a mutex. As long as
PWM and GPIO's respective request/free functions modify the in-use
bitmap while holding the mutex, proper synchronization will be
guaranteed.

Reported-by: YueHaibing <yuehaibing@huawei.com>
Fixes: e926b12c61 ("pwm: Clear chip_data in pwm_put()")
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: YueHaibing <yuehaibing@huawei.com>
Link: https://lkml.org/lkml/2019/5/31/963
Signed-off-by: Sven Van Asbroeck <TheSven73@gmail.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[cg: Tested on an i.MX6Q board with two NXP PCA9685 chips]
Tested-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Reviewed-by: Sven Van Asbroeck <TheSven73@gmail.com> # cg's rebase
Link: https://lore.kernel.org/lkml/20200330160238.GD2817345@ulmo/
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-21 09:04:52 +02:00
Uwe Kleine-König
f68b6a015a pwm: omap-dmtimer: put_device() after of_find_device_by_node()
commit c7cb3a1dd5 upstream.

This was found by coccicheck:

	drivers/pwm/pwm-omap-dmtimer.c:304:2-8: ERROR: missing put_device;
	call of_find_device_by_node on line 255, but without a corresponding
	object release within this function.

Reported-by: Markus Elfring <elfring@users.sourceforge.net>
Fixes: 6604c6556d ("pwm: Add PWM driver for OMAP using dual-mode timers")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-05 16:43:49 +01:00
yu kuai
50b9336966 pwm: Remove set but not set variable 'pwm'
[ Upstream commit 9871abffc8 ]

Fixes gcc '-Wunused-but-set-variable' warning:

	drivers/pwm/pwm-pca9685.c: In function ‘pca9685_pwm_gpio_free’:
	drivers/pwm/pwm-pca9685.c:162:21: warning: variable ‘pwm’ set but not used [-Wunused-but-set-variable]

It is never used, and so can be removed. In that case, hold and release
the lock 'pca->lock' can be removed since nothing will be done between
them.

Fixes: e926b12c61 ("pwm: Clear chip_data in pwm_put()")
Signed-off-by: yu kuai <yukuai3@huawei.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-24 08:36:53 +01:00
Uwe Kleine-König
419035d75d pwm: omap-dmtimer: Remove PWM chip in .remove before making it unfunctional
[ Upstream commit 43efdc8f0e ]

In the old code (e.g.) mutex_destroy() was called before
pwmchip_remove(). Between these two calls it is possible that a PWM
callback is used which tries to grab the mutex.

Fixes: 6604c6556d ("pwm: Add PWM driver for OMAP using dual-mode timers")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-24 08:36:53 +01:00
Uwe Kleine-König
a3536e5589 pwm: omap-dmtimer: Simplify error handling
[ Upstream commit c4cf7aa57e ]

Instead of doing error handling in the middle of ->probe(), move error
handling and freeing the reference to timer to the end.

This fixes a resource leak as dm_timer wasn't freed when allocating
*omap failed.

Implementation note: The put: label was never reached without a goto and
ret being unequal to 0, so the removed return statement is fine.

Fixes: 6604c6556d ("pwm: Add PWM driver for OMAP using dual-mode timers")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-24 08:36:29 +01:00
Ondrej Jirman
e70290bb1f pwm: sun4i: Fix incorrect calculation of duty_cycle/period
[ Upstream commit 50cc7e3e4f ]

Since 5.4-rc1, pwm_apply_state calls ->get_state after ->apply
if available, and this revealed an issue with integer precision
when calculating duty_cycle and period for the currently set
state in ->get_state callback.

This issue manifested in broken backlight on several Allwinner
based devices.

Previously this worked, because ->apply updated the passed state
directly.

Fixes: deb9c462f4 ("pwm: sun4i: Don't update the state for the caller of pwm_apply_state")
Signed-off-by: Ondrej Jirman <megous@megous.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-26 10:01:04 +01:00
Uwe Kleine-König
24906a41ee pwm: bcm-iproc: Prevent unloading the driver module while in use
The owner member of struct pwm_ops must be set to THIS_MODULE to
increase the reference count of the module such that the module cannot
be removed while its code is in use.

Fixes: daa5abc41c ("pwm: Add support for Broadcom iProc PWM controller")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-11-08 18:38:06 +01:00
Thierry Reding
40a6b9a009 Revert "pwm: Let pwm_get_state() return the last implemented state"
It turns out that commit 01ccf903ed ("pwm: Let pwm_get_state() return
the last implemented state") causes backlight failures on a number of
boards. The reason is that some of the drivers do not write the full
state through to the hardware registers, which means that ->get_state()
subsequently does not return the correct state. Consumers which rely on
pwm_get_state() returning the current state will therefore get confused
and subsequently try to program a bad state.

Before this change can be made, existing drivers need to be more
carefully audited and fixed to behave as the framework expects. Until
then, keep the original behaviour of returning the software state that
was applied rather than reading the state back from hardware.

Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Tested-by: Michal Vokáč <michal.vokac@ysoft.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-10-21 16:48:52 +02:00
Linus Torvalds
e37e3bc7e2 pwm: Changes for v5.4-rc1
Besides one new driver being added for the PWM controller found in
 various Spreadtrum SoCs, this series of changes brings a slew of, mostly
 minor, fixes and cleanups for existing drivers, as well as some
 enhancements to the core code.
 
 Lastly, Uwe is added to the PWM subsystem entry of the MAINTAINERS file,
 making official his role as a reviewer.
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Merge tag 'pwm/for-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
 "Besides one new driver being added for the PWM controller found in
  various Spreadtrum SoCs, this series of changes brings a slew of,
  mostly minor, fixes and cleanups for existing drivers, as well as some
  enhancements to the core code.

  Lastly, Uwe is added to the PWM subsystem entry of the MAINTAINERS
  file, making official his role as a reviewer"

* tag 'pwm/for-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: (34 commits)
  MAINTAINERS: Add myself as reviewer for the PWM subsystem
  MAINTAINERS: Add patchwork link for PWM entry
  MAINTAINERS: Add a selection of PWM related keywords to the PWM entry
  pwm: mediatek: Add MT7629 compatible string
  dt-bindings: pwm: Update bindings for MT7629 SoC
  pwm: mediatek: Update license and switch to SPDX tag
  pwm: mediatek: Use pwm_mediatek as common prefix
  pwm: mediatek: Allocate the clks array dynamically
  pwm: mediatek: Remove the has_clks field
  pwm: mediatek: Drop the check for of_device_get_match_data()
  pwm: atmel: Consolidate driver data initialization
  pwm: atmel: Remove unneeded check for match data
  pwm: atmel: Remove platform_device_id and use only dt bindings
  pwm: stm32-lp: Add check in case requested period cannot be achieved
  pwm: Ensure pwm_apply_state() doesn't modify the state argument
  pwm: fsl-ftm: Don't update the state for the caller of pwm_apply_state()
  pwm: sun4i: Don't update the state for the caller of pwm_apply_state()
  pwm: rockchip: Don't update the state for the caller of pwm_apply_state()
  pwm: Let pwm_get_state() return the last implemented state
  pwm: Introduce local struct pwm_chip in pwm_apply_state()
  ...
2019-09-27 12:19:47 -07:00
Sam Shih
715d14da67 pwm: mediatek: Add MT7629 compatible string
This adds pwm support for MT7629, and separate mt7629 compatible string
from mt7622

Signed-off-by: Sam Shih <sam.shih@mediatek.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-26 13:27:50 +02:00
Sam Shih
4bea6dd5be pwm: mediatek: Update license and switch to SPDX tag
Add SPDX identifiers to pwm-mediatek.c. Update MODULE_LICENSE to
correctly reflect the GNU General Public License v2.0.

Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Sam Shih <sam.shih@mediatek.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-25 09:49:15 +02:00
Sam Shih
2503781c97 pwm: mediatek: Use pwm_mediatek as common prefix
Use pwm_mediatek as common prefix to match the filename. No functional
change intended.

Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Sam Shih <sam.shih@mediatek.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-25 09:49:15 +02:00
Sam Shih
efecdeb82f pwm: mediatek: Allocate the clks array dynamically
Instead of using fixed size of arrays, allocate the memory for them
based on the number of PWMs specified for each SoC generation.

Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Sam Shih <sam.shih@mediatek.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-25 09:49:15 +02:00
Sam Shih
61aa258ab1 pwm: mediatek: Remove the has_clks field
We can use fixed clocks to repair mt7628 PWM during configure from
userspace. The SoC is legacy MIPS and has no complex clock tree. Because
we can get the clock frequency for period calculation from fixed clocks
specified in DT, we can remove the has_clock field, and directly use
devm_clk_get() and clk_get_rate().

Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Sam Shih <sam.shih@mediatek.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-25 09:48:58 +02:00
Sam Shih
e6c7c258f0 pwm: mediatek: Drop the check for of_device_get_match_data()
This patch drop the check for of_device_get_match_data. Due to the only
way call driver probe is compatible match. The data pointer which points
to the SoC specify data is directly set by driver, and it should not be
NULL in our case. We can safety remove the check for the result of
of_device_get_match_data().

Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Sam Shih <sam.shih@mediatek.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21 03:25:11 +02:00
Thierry Reding
9193c16e5a pwm: atmel: Consolidate driver data initialization
This helps readability by separating the driver-specific bits from the
PWM framework bits.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21 03:25:11 +02:00
Thierry Reding
d85b9ce198 pwm: atmel: Remove unneeded check for match data
Since the driver is now exclusively DT, it only binds if it finds a
match in the of_device_id table. But in that case the associated data
can never be NULL, so drop the unnecessary check.

While at it, drop the extra local variable and store the pointer to
this per-SoC data in the driver data directly.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21 03:25:11 +02:00
Kamel Bouhara
3d4d85741a pwm: atmel: Remove platform_device_id and use only dt bindings
Since commit 26202873bb ("avr32: remove support for AVR32
architecture") there is no more user of platform_device_id and we
should only use dt bindings

Signed-off-by: Kamel Bouhara <kamel.bouhara@bootlin.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21 03:25:10 +02:00
Fabrice Gasnier
c91e3234c6 pwm: stm32-lp: Add check in case requested period cannot be achieved
LPTimer can use a 32KHz clock for counting. It depends on clock tree
configuration. In such a case, PWM output frequency range is limited.
Although unlikely, nothing prevents user from requesting a PWM frequency
above counting clock (32KHz for instance):
- This causes (prd - 1) = 0xffff to be written in ARR register later in
the apply() routine.
This results in badly configured PWM period (and also duty_cycle).
Add a check to report an error is such a case.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21 03:25:10 +02:00
Uwe Kleine-König
71523d1812 pwm: Ensure pwm_apply_state() doesn't modify the state argument
It is surprising for a PWM consumer when the variable holding the
requested state is modified by pwm_apply_state(). Consider for example a
driver doing:

        #define PERIOD 5000000
        #define DUTY_LITTLE 10
        ...
        struct pwm_state state = {
                .period = PERIOD,
                .duty_cycle = DUTY_LITTLE,
                .polarity = PWM_POLARITY_NORMAL,
                .enabled = true,
        };

        pwm_apply_state(mypwm, &state);
        ...
        state.duty_cycle = PERIOD / 2;
        pwm_apply_state(mypwm, &state);

For sure the second call to pwm_apply_state() should still have
state.period = PERIOD and not something the hardware driver chose for a
reason that doesn't necessarily apply to the second call.

So declare the state argument as a pointer to a const type and adapt all
drivers' .apply callbacks.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21 03:25:10 +02:00
Uwe Kleine-König
c9675829ba pwm: fsl-ftm: Don't update the state for the caller of pwm_apply_state()
The pwm-fsl-ftm driver is one of only three PWM drivers which updates
the state for the caller of pwm_apply_state(). This might have
surprising results if the caller reuses the values expecting them to
still represent the same state.

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21 01:48:55 +02:00
Uwe Kleine-König
deb9c462f4 pwm: sun4i: Don't update the state for the caller of pwm_apply_state()
The pwm-sun4i driver is one of only three PWM drivers which updates the
state for the caller of pwm_apply_state(). This might have surprising
results if the caller reuses the values expecting them to still
represent the same state.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21 01:48:55 +02:00
Uwe Kleine-König
797a5ebc26 pwm: rockchip: Don't update the state for the caller of pwm_apply_state()
The pwm-rockchip driver is one of only three PWM drivers which updates
the state for the caller of pwm_apply_state(). This might have
surprising results if the caller reuses the values expecting them to
still represent the same state.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21 01:48:55 +02:00
Uwe Kleine-König
01ccf903ed pwm: Let pwm_get_state() return the last implemented state
When pwm_apply_state() is called the lowlevel driver usually has to
apply some rounding because the hardware doesn't support nanosecond
resolution. So let pwm_get_state() return the actually implemented state
instead of the last applied one if possible.

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21 01:48:54 +02:00
Uwe Kleine-König
fc3c5512e3 pwm: Introduce local struct pwm_chip in pwm_apply_state()
pwm->chip is dereferenced several times in the pwm_apply_state()
function. Introducing a local variable for it helps keeping some lines a
bit shorter.

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21 01:48:54 +02:00
Uwe Kleine-König
ba73deb16f pwm: rockchip: Set polarity unconditionally in .get_state()
Don't rely on *state being zero initialized and PWM_POLARITY_NORMAL
being zero. So always assign .polarity.

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21 01:48:54 +02:00
Stefan Wahren
9e3ca01f7e pwm: bcm2835: Suppress error message during deferred probe
This suppresses error messages in case the PWM clock isn't ready yet.

Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21 01:24:11 +02:00
Stefan Wahren
7e9713af31 pwm: bcm2835: Fix period_ns range check
The range check for period_ns was written under assumption of a fixed
PWM clock. With clk-bcm2835 driver the PWM clock is a dynamic one.
So fix this by doing the range check on the period register value.

Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-09-21 01:23:24 +02:00