Commit Graph

15 Commits

Author SHA1 Message Date
Simon South 130c2c0d9b pwm: rockchip: rockchip_pwm_probe(): Remove superfluous clk_unprepare()
[ Upstream commit d5d8d675865ccddfe4da26c85f22c55cec663bf2 ]

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: 48cf973cae33 ("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>
2021-04-12 12:52:30 +08:00
Lokesh Vutla 6739b90d69 pwm: lp3943: Dynamically allocate PWM chip base
[ Upstream commit 1f0f1e80fdd3aa9631f6c22cda4f8550cfcfcc3e ]

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: af66b3c0934e ("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>
2021-03-16 16:43:18 +08:00
Uwe Kleine-König 159a914733 pwm: zx: Add missing cleanup in error path
[ Upstream commit 269effd03f6142df4c74814cfdd5f0b041b30bf9 ]

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

Fixes: 4836193c435c ("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>
2021-03-16 16:43:17 +08:00
Hauke Mehrtens c199f8aef2 pwm: img: Fix null pointer access in probe
[ Upstream commit b39c0615d0667b3a6f2f5c4bf99ffadf3b518bb1 ]

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: e690ae526216 ("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>
2021-03-16 16:39:01 +08:00
Hans de Goede 85b15300dd pwm: lpss: Add range limit check for the base_unit register value
[ Upstream commit ef9f60daab309558c8bb3e086a9a11ee40bd6061 ]

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: 684309e5043e ("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>
2021-03-16 16:38:36 +08:00
Hans de Goede 3b0f655811 pwm: lpss: Fix off by one error in base_unit math in pwm_lpss_prepare()
[ Upstream commit 181f4d2f44463fe09fe4df02e03095cb87151c29 ]

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 684309e5043e ("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: 684309e5043e ("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>
2021-03-16 16:38:36 +08:00
Rayagonda Kokatanur 4914609e44 pwm: bcm-iproc: handle clk_get_rate() return
[ Upstream commit 6ced5ff0be8e94871ba846dfbddf69d21363f3d7 ]

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

Fixes: daa5abc41c80 ("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>
2021-03-16 16:34:17 +08:00
Uwe Kleine-König 8349172c92 pwm: jz4740: Fix build failure
When commit 9017dc4fbd59 ("pwm: jz4740: Enhance precision in calculation
of duty cycle") from v5.8-rc1 was backported to v5.4.x its dependency on
commit ce1f9cece057 ("pwm: jz4740: Use clocks from TCU driver") was not
noticed which made the pwm-jz4740 driver fail to build.

As ce1f9cece057 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 ce1f9cece057, 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>
2021-03-16 16:31:41 +08:00
Paul Cercueil 8ab65b19f0 pwm: jz4740: Enhance precision in calculation of duty cycle
commit 9017dc4fbd59c09463019ce494cfe36d654495a8 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: f6b8a5700057 ("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>
2021-03-16 16:30:44 +08:00
Navid Emamdoost f93573d403 pwm: img: Call pm_runtime_put() in pm_runtime_get_sync() failed case
[ Upstream commit ca162ce98110b98e7d97b7157328d34dcfdd40a9 ]

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>
2021-03-16 16:30:05 +08:00
Florian Fainelli 495213eb65 pwm: bcm2835: Dynamically allocate base
[ Upstream commit 2c25b07e5ec119cab609e41407a1fb3fa61442f5 ]

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: e5a06dc5ac1f ("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>
2021-03-16 16:26:47 +08:00
Geert Uytterhoeven 9b773312e5 pwm: renesas-tpu: Fix late Runtime PM enablement
[ Upstream commit d5a3c7a4536e1329a758e14340efd0e65252bd3d ]

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: 99b82abb0a35b073 ("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>
2021-03-16 16:26:47 +08:00
Geert Uytterhoeven f6195548f6 pwm: rcar: Fix late Runtime PM enablement
[ Upstream commit 1451a3eed24b5fd6a604683f0b6995e0e7e16c79 ]

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: ed6c1476bf7f16d5 ("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>
2021-03-16 16:26:44 +08:00
Sven Van Asbroeck 0c272cb5c8 pwm: pca9685: Fix PWM/GPIO inter-operation
commit 9cc5f232a4b6a0ef6e9b57876d61b88f61bdd7c2 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 e926b12c611c ("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: e926b12c611c ("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>
2021-03-16 16:26:23 +08:00
Kaixu Xia 590eaf1fec Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.
Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
2021-03-16 11:01:34 +08:00