kernel/linux.git/drivers/pwm, branch v5.4.113

pwm: rockchip: rockchip_pwm_probe(): Remove superfluous clk_unprepare()

2021-03-04T09:26:36+00:00

[ 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 Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin

pwm: lp3943: Dynamically allocate PWM chip base

2020-12-30T10:51:28+00:00

[ 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 Reviewed-by: Uwe Kleine-König Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin

pwm: zx: Add missing cleanup in error path

2020-12-30T10:51:28+00:00

[ 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 Acked-by: Shawn Guo Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin

pwm: img: Fix null pointer access in probe

2020-10-29T08:57:54+00:00

[ 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 Acked-by: Lee Jones Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin

pwm: lpss: Add range limit check for the base_unit register value

2020-10-29T08:57:38+00:00

[ 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 Acked-by: Thierry Reding Signed-off-by: Hans de Goede Link: https://patchwork.freedesktop.org/patch/msgid/20200903112337.4113-5-hdegoede@redhat.com Signed-off-by: Sasha Levin

pwm: lpss: Fix off by one error in base_unit math in pwm_lpss_prepare()

2020-10-29T08:57:38+00:00

[ 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 Acked-by: Uwe Kleine-König Acked-by: Thierry Reding Signed-off-by: Hans de Goede Link: https://patchwork.freedesktop.org/patch/msgid/20200903112337.4113-4-hdegoede@redhat.com Signed-off-by: Sasha Levin

pwm: bcm-iproc: handle clk_get_rate() return

2020-08-21T11:05:34+00:00

[ 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 Signed-off-by: Scott Branden Reviewed-by: Ray Jui Reviewed-by: Uwe Kleine-König Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin

pwm: jz4740: Fix build failure

2020-07-16T06:16:48+00:00

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 Reported-by: H. Nikolaus Schaller Signed-off-by: Greg Kroah-Hartman

pwm: jz4740: Enhance precision in calculation of duty cycle

2020-06-24T15:50:52+00:00

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: Suggested-by: Uwe Kleine-König Reviewed-by: Uwe Kleine-König Signed-off-by: Paul Cercueil Signed-off-by: Thierry Reding [ukl: backport to v5.4.y and adapt commit log accordingly] Signed-off-by: Uwe Kleine-König Signed-off-by: Greg Kroah-Hartman

pwm: img: Call pm_runtime_put() in pm_runtime_get_sync() failed case

2020-06-24T15:50:18+00:00

[ 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 Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin