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path: root/drivers/pwm
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2022-08-04Merge tag 'spdx-6.0-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx Pull SPDX updates from Greg KH: "Here is the set of SPDX comment updates for 6.0-rc1. Nothing huge here, just a number of updated SPDX license tags and cleanups based on the review of a number of common patterns in GPLv2 boilerplate text. Also included in here are a few other minor updates, two USB files, and one Documentation file update to get the SPDX lines correct. All of these have been in the linux-next tree for a very long time" * tag 'spdx-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx: (28 commits) Documentation: samsung-s3c24xx: Add blank line after SPDX directive x86/crypto: Remove stray comment terminator treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_406.RULE treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_398.RULE treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_391.RULE treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_390.RULE treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_385.RULE treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_320.RULE treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_319.RULE treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_318.RULE treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_298.RULE treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_292.RULE treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_179.RULE treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_168.RULE (part 2) treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_168.RULE (part 1) treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_160.RULE treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_152.RULE treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_149.RULE treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_147.RULE treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_133.RULE ...
2022-07-29pwm: lpc18xx: Fix period handlingUwe Kleine-König
The calculation: val = (u64)NSEC_PER_SEC * LPC18XX_PWM_TIMER_MAX; do_div(val, lpc18xx_pwm->clk_rate); lpc18xx_pwm->max_period_ns = val; is bogus because with NSEC_PER_SEC = 1000000000, LPC18XX_PWM_TIMER_MAX = 0xffffffff and clk_rate < NSEC_PER_SEC this overflows the (on lpc18xx (i.e. ARM32) 32 bit wide) unsigned int .max_period_ns. This results (dependant of the actual clk rate) in an arbitrary limitation of the maximal period. E.g. for clkrate = 333333333 (Hz) we get max_period_ns = 9 instead of 12884901897. So make .max_period_ns an u64 and pass period and duty as u64 to not discard relevant digits. And also make use of mul_u64_u64_div_u64() which prevents all overflows assuming clk_rate < NSEC_PER_SEC. Fixes: 841e6f90bb78 ("pwm: NXP LPC18xx PWM/SCT driver") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-07-29pwm: lpc18xx: Convert to use dev_err_probe()Uwe Kleine-König
This has various upsides: - It emits the symbolic name of the error code - It is silent in the EPROBE_DEFER case and properly sets the defer reason - It reduces the number of code lines slightly Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-07-29pwm: twl-led: Document some limitations and link to the reference manualUwe Kleine-König
I found these just from reading the reference manual and the driver source. It's unclear to me if there are glitches when updating the ON and OFF registers. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-07-29pwm: Add clock based PWM output driverNikita Travkin
Some systems have clocks exposed to external devices. If the clock controller supports duty-cycle configuration, such clocks can be used as pwm outputs. In fact PWM and CLK subsystems are interfaced with in a similar way and an "opposite" driver already exists (clk-pwm). Add a driver that would enable pwm devices to be used via clk subsystem. Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Nikita Travkin <nikita@trvn.ru> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-07-29pwm: sifive: Shut down hardware only after pwmchip_remove() completedUwe Kleine-König
The PWMs are expected to be functional until pwmchip_remove() is called. So disable the clks only afterwards. Fixes: 9e37a53eb051 ("pwm: sifive: Add a driver for SiFive SoC PWM") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Tested-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-07-29pwm: sifive: Ensure the clk is enabled exactly once per running PWMUwe Kleine-König
.apply() assumes the clk to be for a given PWM iff the PWM is enabled. So make sure this is the case when .probe() completes. And in .remove() disable the according number of times. This fixes a clk enable/disable imbalance, if some PWMs are already running at probe time. Fixes: 9e37a53eb051 (pwm: sifive: Add a driver for SiFive SoC PWM) Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Tested-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-07-29pwm: sifive: Simplify clk handlingUwe Kleine-König
The clk is necessary for both register access and (enabled) operation of the PWM. Instead of clk_enable() update_hw() if pwm_got_enabled(): clk_enable() elif pwm_got_disabled(): clk_disable() clk_disable() which is some cases only calls clk_enable() to immediately afterwards call clk_disable again, do: if (!prev_state.enabled) clk_enable() # clk enabled exactly once update_hw() if (!next_state.enabled) clk_disable() which is much easier. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Tested-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-07-29pwm: sifive: Enable clk only after period check in .apply()Uwe Kleine-König
For the period check and the initial calculations of register values there is no hardware access needed. So delay enabling the clk a bit to simplify the code flow a bit. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Tested-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-07-29pwm: sifive: Reduce time the controller lock is heldUwe Kleine-König
The lock is only to serialize access and update to user_count and approx_period between different PWMs served by the same pwm_chip. So the lock needs only to be taken during the check if the (chip global) period can and/or needs to be changed. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Tested-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-07-29pwm: sifive: Fold pwm_sifive_enable() into its only callerUwe Kleine-König
There is only a single caller of pwm_sifive_enable() which only enables or disables the clk. Put this implementation directly into pwm_sifive_apply() which allows further simplification in the next change. There is no change in behaviour. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Tested-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-07-29pwm: sifive: Simplify offset calculation for PWMCMP registersUwe Kleine-König
Instead of explicitly using PWM_SIFIVE_PWMCMP0 + pwm->hwpwm * PWM_SIFIVE_SIZE_PWMCMP for each access to one of the PWMCMP registers, introduce a macro that takes the hwpwm id as parameter. For the register definition using a plain 4 instead of the cpp constant PWM_SIFIVE_SIZE_PWMCMP is easier to read, so define the offset macro without the constant. The latter can then be dropped as there are no users left. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Tested-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-06-22pwm: mediatek: Add MT8365 supportFabien Parent
Add support for PWM on MT8365. Signed-off-by: Fabien Parent <fparent@baylibre.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-06-22pwm: atmel-tcb: Fix typo in commentJulia Lawall
Spelling mistake (triple letters) in comment. Detected with the help of Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-06-22pwm: Drop support for legacy driversUwe Kleine-König
There are no drivers left providing the legacy callbacks. So drop support for these. If this commit breaks your out-of-tree pwm driver, look at e.g. commit ec00cd5e63f0 ("pwm: renesas-tpu: Implement .apply() callback") for an example of the needed conversion for your driver. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-06-10treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_30.RULE ↵Thomas Gleixner
(part 2) Based on the normalized pattern: this program is free software you can redistribute it and/or modify it under the terms of the gnu general public license as published by the free software foundation version 2 this program is distributed as is without any warranty of any kind whether express or implied without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference. Reviewed-by: Allison Randal <allison@lohutok.net> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-20pwm: pwm-cros-ec: Add channel type supportFabio Baltieri
Add support for EC_PWM_TYPE_DISPLAY_LIGHT and EC_PWM_TYPE_KB_LIGHT pwm types to the PWM cros_ec_pwm driver. This allows specifying one of these PWM channel by functionality, and let the EC firmware pick the correct channel, thus abstracting the hardware implementation from the kernel driver. To use it, define the node with the "google,cros-ec-pwm-type" compatible. Signed-off-by: Fabio Baltieri <fabiobaltieri@chromium.org> Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: twl-led: Implement .apply() callbackUwe Kleine-König
To eventually get rid of all legacy drivers convert this driver to the modern world implementing .apply(). This just pushed a variant of pwm_apply_legacy() into the driver that was slightly simplified because the driver doesn't provide a .set_polarity() callback. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: lpc18xx: Implement .apply() callbackUwe Kleine-König
To eventually get rid of all legacy drivers convert this driver to the modern world implementing .apply(). This pushes a variant of pwm_apply_legacy into the driver that was slightly simplified because the .set_polarity callback was a noop. There is no change in behavior. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: mediatek: Implement .apply() callbackUwe Kleine-König
To eventually get rid of all legacy drivers convert this driver to the modern world implementing .apply(). This just pushed a variant of pwm_apply_legacy() into the driver that was slightly simplified because the driver doesn't provide a .set_polarity() callback. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: lpc32xx: Implement .apply() callbackUwe Kleine-König
To eventually get rid of all legacy drivers convert this driver to the modern world implementing .apply(). This just pushed a variant of pwm_apply_legacy() into the driver that was slightly simplified because the driver doesn't provide a .set_polarity() callback. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: tegra: Implement .apply() callbackUwe Kleine-König
To eventually get rid of all legacy drivers convert this driver to the modern world implementing .apply(). This just pushed a variant of pwm_apply_legacy() into the driver that was slightly simplified because the driver doesn't provide a .set_polarity() callback. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: stmpe: Implement .apply() callbackUwe Kleine-König
To eventually get rid of all legacy drivers convert this driver to the modern world implementing .apply(). This just pushed a variant of pwm_apply_legacy() into the driver that was slightly simplified because the driver doesn't provide a .set_polarity() callback. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: sti: Implement .apply() callbackUwe Kleine-König
To eventually get rid of all legacy drivers convert this driver to the modern world implementing .apply(). This just pushed a variant of pwm_apply_legacy() into the driver that was slightly simplified because the driver doesn't provide a .set_polarity() callback. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: pwm-mediatek: Add support for MediaTek Helio X10 MT6795AngeloGioacchino Del Regno
The MediaTek Helio X10 MT6795 SoC has 7 PWMs: add a compatible string to use the right match data. Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: tegra: Optimize period calculationUwe Kleine-König
Dividing by the result of a division looses precision because the result is rounded twice. E.g. with clk_rate = 48000000 and period = 32760033 the following numbers result: rate = pc->clk_rate >> PWM_DUTY_WIDTH = 187500 hz = DIV_ROUND_CLOSEST_ULL(100ULL * NSEC_PER_SEC, period_ns) = 3052 rate = DIV_ROUND_CLOSEST_ULL(100ULL * rate, hz) = 6144 The exact result would be 6142.5061875 and (apart from rounding) this is found by using a single division. As a side effect is also a tad cheaper to calculate. Also using clk_rate >> PWM_DUTY_WIDTH looses precision. Consider for example clk_rate = 47999999 and period = 106667: mul_u64_u64_div_u64(pc->clk_rate >> PWM_DUTY_WIDTH, period_ns, NSEC_PER_SEC) = 19 mul_u64_u64_div_u64(pc->clk_rate, period_ns, NSEC_PER_SEC << PWM_DUTY_WIDTH) = 20 (The exact result is 20.000062083332033.) With this optimizations also switch from round-closest to round-down for the period calculation. Given that the calculations were non-optimal for quite some time now with variations in both directions which nobody reported as a problem, this is the opportunity to align the driver's behavior to the requirements of new drivers. This has several upsides: - Implementation is easier as there are no round-nearest variants of mul_u64_u64_div_u64(). - Requests for too small periods are now consistently refused. This was kind of arbitrary before, where period_ns < min_period_ns was refused, but in some cases min_period_ns isn't actually implementable and then values between min_period_ns and the actual minimum were rounded up to the actual minimum. Note that the duty_cycle calculation isn't using the usual round-down approach yet. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: renesas-tpu: Improve precision of period and duty_cycle calculationUwe Kleine-König
Dividing by the result of a division looses precision. Consider for example clk_rate = 33000000 and period_ns = 500001. Then clk_rate / (NSEC_PER_SEC / period_ns) has the exact value 16500.033, but in C this evaluates to 16508. It gets worse for even bigger values of period_ns, so with period_ns = 500000001, the exact result is 16500000.033 while in C we get 33000000. For that reason use clk_rate * period_ns / NSEC_PER_SEC instead which doesn't suffer from this problem. To ensure this doesn't overflow add a safeguard check for clk_rate. Note that duty > period can never happen, so the respective check can be dropped. Incidentally this fixes a division by zero if period_ns > NSEC_PER_SEC. Another side effect is that values bigger than INT_MAX for period and duty_cyle are not wrongly discarded any more. Fixes: 99b82abb0a35 ("pwm: Add Renesas TPU PWM driver") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: renesas-tpu: Improve maths to compute register settingsUwe Kleine-König
The newly computed register values are intended to exactly match the previously computed values. The main improvement is that the prescaler is computed without a loop that involves two divisions in each step. This uses the fact, that prescalers[i] = 1 << (2 * i). Assuming a moderately smart compiler, the needed number of divisions for the case where the requested period is too big, is reduced from 5 to 2. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: renesas-tpu: Rename variables to match the usual namingUwe Kleine-König
The driver used "pwm" for struct tpu_pwm_device pointers. This name is usually only used for struct pwm_device pointers which this driver calls "_pwm". So rename to the driver data pointers to "tpd" which then allows to drop the underscore from "_pwm". Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: renesas-tpu: Implement .apply() callbackUwe Kleine-König
To eventually get rid of all legacy drivers convert this driver to the modern world implementing .apply(). As pwm->state might not be updated in tpu_pwm_apply() before calling tpu_pwm_config(), an additional parameter is needed for tpu_pwm_config() to not change the implemented logic. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: renesas-tpu: Make use of devm functionsUwe Kleine-König
This simplifies an error path in .probe() and allows to drop the .remove() function. Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: renesas-tpu: Make use of dev_err_probe()Uwe Kleine-König
The added benefit is that the error code is mentioned in the error message and its usage is a bit more compact than open coding it. This also improves behaviour in case devm_clk_get() returns -EPROBE_DEFER. While touching this code, consistently start error messages with upper case. Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: samsung: Implement .apply() callbackUwe Kleine-König
To eventually get rid of all legacy drivers convert this driver to the modern world implementing .apply(). The size check for state->period is moved to .apply() to make sure that the values of state->duty_cycle and state->period are passed to pwm_samsung_config without change while they are discarded to int. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-05-20pwm: sifive: Simplify if-if to if-elseWan Jiabing
Use if and else instead of if(A) and if (!A). Signed-off-by: Wan Jiabing <wanjiabing@vivo.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-04-22pwm: clps71xx: Implement .apply() callbackUwe Kleine-König
To eventually get rid of all legacy drivers convert this driver to the modern world implementing .apply(). This fixes a small issue in clps711x_get_duty() en passant: the multiplication v * 0xf might have overflown. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-04-22pwm: raspberrypi-poe: Fix endianness in firmware structUwe Kleine-König
The reg member of struct raspberrypi_pwm_prop is a little endian 32 bit quantity. Explicitly convert the (native endian) value to little endian on assignment as is already done in raspberrypi_pwm_set_property(). This fixes the following sparse warning: drivers/pwm/pwm-raspberrypi-poe.c:69:24: warning: incorrect type in initializer (different base types) drivers/pwm/pwm-raspberrypi-poe.c:69:24: expected restricted __le32 [usertype] reg drivers/pwm/pwm-raspberrypi-poe.c:69:24: got unsigned int [usertype] reg Fixes: 79caa362eab6 ("pwm: Add Raspberry Pi Firmware based PWM bus") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-04-22pwm: atmel-tcb: Make atmel_tcb_divisors staticUwe Kleine-König
The array atmel_tcb_divisors is not supposed to be used outside of the driver, so make it static. This fixes a sparse warning: drivers/pwm/pwm-atmel-tcb.c:64:10: warning: symbol 'atmel_tcb_divisors' was not declared. Should it be static? Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-04-22pwm: lp3943: Implement .apply() callbackUwe Kleine-König
To eventually get rid of all legacy drivers convert this driver to the modern world implementing .apply(). Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-04-22pwm: lp3943: Fix duty calculation in case period was clampedUwe Kleine-König
The hardware only supports periods <= 1.6 ms and if a bigger period is requested it is clamped to 1.6 ms. In this case duty_cycle might be bigger than 1.6 ms and then the duty cycle register is written with a value bigger than LP3943_MAX_DUTY. So clamp duty_cycle accordingly. Fixes: af66b3c0934e ("pwm: Add LP3943 PWM driver") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-04-22pwm: sunplus-pwm: Add Sunplus SoC SP7021 PWM DriverHammer Hsieh
Add Sunplus SoC SP7021 PWM Driver Signed-off-by: Hammer Hsieh <hammerh0314@gmail.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-04-22pwm: Add support for Xilinx AXI TimerSean Anderson
This adds PWM support for Xilinx LogiCORE IP AXI soft timers commonly found on Xilinx FPGAs. At the moment clock control is very basic: we just enable the clock during probe and pin the frequency. In the future, someone could add support for disabling the clock when not in use. Some common code has been specially demarcated. While currently only used by the PWM driver, it is anticipated that it may be split off in the future to be used by the timer driver as well. This driver was written with reference to Xilinx DS764 for v1.03.a [1]. [1] https://www.xilinx.com/support/documentation/ip_documentation/axi_timer/v1_03_a/axi_timer_ds764.pdf Signed-off-by: Sean Anderson <sean.anderson@seco.com> Acked-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-04-22pwm: atmel-tcb: Drop duplicated tracking of per-channel dataUwe Kleine-König
Per-channel data is tracked using struct pwm_device::chip_data and struct atmel_tcb_pwm_chip::pwms[]. Simplify by using the latter consistently. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-04-22pwm-sun4i: Calculate the delay without rounding down to jiffiesMax Kellermann
This fixes a problem that was supposed to be addressed by commit 6eefb79d6f5bc ("pwm: sun4i: Remove erroneous else branch") - backlight could not be switched off on some Allwinner A20. The commit was correct, but was not a reliable fix for the problem, which was timing related. The real problem for the backlight switching problem was that sleeping for a full period did not work, because delay_us is always zero. It is zero because the period (plus 1 microsecond) is rounded down to the next "jiffies", but the period is less than one jiffy. On my Cubieboard 2, the period is 5ms, and 1 jiffy (at the default HZ=100) is 10ms, so nsecs_to_jiffies(10ms+1us)=0. The roundtrip from nanoseconds to jiffies and back to microseconds is an unnecessary loss of precision; always rounding down (via nsecs_to_jiffies()) then causes the breakage. This patch eliminates this roundtrip, and directly converts from nanoseconds to microseconds (for usleep_range()), using DIV_ROUND_UP_ULL() to force rounding up. This way, the sleep time is never zero, and after the sleep, we are guaranteed to be in a different period, and the device is ready for another control command for sure. Signed-off-by: Max Kellermann <max.kellermann@gmail.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-04-22pwm-sun4i: Calculate "delay_jiffies" directly, eliminate absolute timeMax Kellermann
Basically this code did "jiffies + period - jiffies", and we can simply eliminate the "jiffies" time stamp here. Signed-off-by: Max Kellermann <max.kellermann@gmail.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-04-22pwm-sun4i: Convert "next_period" to local variableMax Kellermann
Its value is calculated in sun4i_pwm_apply() and is used only there. Signed-off-by: Max Kellermann <max.kellermann@gmail.com> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-02-24pwm: rcar: Simplify multiplication/shift logicGeert Uytterhoeven
- Remove the superfluous cast; the multiplication will yield a 64-bit result due to the "100ULL" anyway, - "a * (1 << b)" == "a << b". Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-02-24pwm: pwm-mediatek: Beautify error messages textAngeloGioacchino Del Regno
As a cherry-on-top cleanup, make error messages clearer to read by changing instances of "clock: XXXX failed" to a more readable "Failed to get XXXX clock". Also add "of" to unsupported period error. This is purely a cosmetic change; no "real" functional changes. Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Reviewed-by: Macpaul Lin <macpaul.lin@mediatek.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-02-24pwm: pwm-mediatek: Allocate clk_pwms with devm_kmalloc_arrayAngeloGioacchino Del Regno
Switch from devm_kcalloc to devm_kmalloc_array when allocating clk_pwms, as this structure is being filled right after allocating it, hence there is no need to zero it out beforehand. Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-02-24pwm: pwm-mediatek: Simplify error handling with dev_err_probe()AngeloGioacchino Del Regno
Use dev_err_probe() to simplify handling errors in pwm_mediatek_probe(). Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-02-24pwm: brcmstb: Remove useless lockingUwe Kleine-König
The lock only protects against concurrent users of the PWM API. This is not expected to be necessary. And if there was such an issue, this is better handled in the PWM core instead as it affects all drivers in the same way. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Tested-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>