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2022-09-28pwm: lpss: Use device_get_match_data() to get device dataAndy Shevchenko1-6/+4
device_get_match_data() in ACPI case calls similar to the acpi_match_device(). We may simplify the code and make it generic by replacing the latter with the former. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-09-28pwm: lpss: Move resource mapping to the glue driversAndy Shevchenko4-10/+14
Move resource mapping to the glue drivers which helps to transform pwm_lpss_probe() to pure library function that may be used by others without need of specific resource management. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-09-28pwm: lpss: Move exported symbols to PWM_LPSS namespaceAndy Shevchenko3-0/+4
Avoid unnecessary pollution of the global symbol namespace by moving library functions in to a specific namespace and import that into the drivers that make use of the functions. For more info: https://lwn.net/Articles/760045/ Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-09-28pwm: lpss: Deduplicate board info data structuresUwe Kleine-König4-51/+39
Move the board info structures from the glue drivers to the common library and hence deduplicate configuration data. For the Intel Braswell case the ACPI version should be used. Because switch to ACPI/PCI is done in BIOS while quite likely the rest of AML code is the same, meaning similar issue might be observed. There is no bug report due to no PCI enabled device in the wild, Andy thinks, and only reference boards can be tested, so nobody really cares about Intel Braswell PCI case. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-09-28pwm: sysfs: Switch to DEFINE_SIMPLE_DEV_PM_OPS() and pm_sleep_ptr()Andy Shevchenko1-4/+4
Using these newer macros allows the compiler to remove the unused structure and functions when !CONFIG_PM_SLEEP + removes the need to mark pm functions __maybe_unused. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-09-28pwm: rockchip: Convert to use dev_err_probe()zhaoxiao1-12/+6
It's fine to call dev_err_probe() in ->probe() when error code is known. Convert the driver to use dev_err_probe(). Signed-off-by: zhaoxiao <zhaoxiao@uniontech.com> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-09-19pwm: core: Make of_pwm_get() staticAndy Shevchenko1-3/+2
There are no users outside of PWM core of the of_pwm_get(). Make it static. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20220826172642.16404-3-andriy.shevchenko@linux.intel.com Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2022-09-19pwm: core: Get rid of unused devm_of_pwm_get()Andy Shevchenko1-30/+0
The devm_of_pwm_get() has recently lost its single user, drop the dead API as well. Note, the new code should use either plain pwm_get() or managed devm_pwm_get() or devm_fwnode_pwm_get() APIs. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20220826172642.16404-2-andriy.shevchenko@linux.intel.com Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2022-08-16i2c: Make remove callback return voidUwe Kleine-König1-3/+1
The value returned by an i2c driver's remove function is mostly ignored. (Only an error message is printed if the value is non-zero that the error is ignored.) So change the prototype of the remove function to return no value. This way driver authors are not tempted to assume that passing an error to the upper layer is a good idea. All drivers are adapted accordingly. There is no intended change of behaviour, all callbacks were prepared to return 0 before. Reviewed-by: Peter Senna Tschudin <peter.senna@gmail.com> Reviewed-by: Jeremy Kerr <jk@codeconstruct.com.au> Reviewed-by: Benjamin Mugnier <benjamin.mugnier@foss.st.com> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Reviewed-by: Crt Mori <cmo@melexis.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Marek Behún <kabel@kernel.org> # for leds-turris-omnia Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Machata <petrm@nvidia.com> # for mlxsw Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com> # for surface3_power Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> # for bmc150-accel-i2c + kxcjk-1013 Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> # for media/* + staging/media/* Acked-by: Miguel Ojeda <ojeda@kernel.org> # for auxdisplay/ht16k33 + auxdisplay/lcd2s Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> # for versaclock5 Reviewed-by: Ajay Gupta <ajayg@nvidia.com> # for ucsi_ccg Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # for iio Acked-by: Peter Rosin <peda@axentia.se> # for i2c-mux-*, max9860 Acked-by: Adrien Grassein <adrien.grassein@gmail.com> # for lontium-lt8912b Reviewed-by: Jean Delvare <jdelvare@suse.de> # for hwmon, i2c-core and i2c/muxes Acked-by: Corey Minyard <cminyard@mvista.com> # for IPMI Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> # for drivers/power Acked-by: Krzysztof Hałasa <khalasa@piap.pl> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-08-04Merge tag 'spdx-6.0-rc1' of ↵Linus Torvalds2-24/+4
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-König1-16/+31
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-König1-11/+9
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-König1-0/+16
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 Travkin3-0/+159
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-König1-2/+3
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-König1-9/+37
.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-König1-13/+13
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-König1-10/+8
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-König1-3/+5
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-König1-20/+8
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-König1-7/+3
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 Parent1-0/+7
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 Lawall1-1/+1
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-König1-81/+1
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 Gleixner2-24/+4
(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 Baltieri1-15/+67
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-König1-10/+66
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-König1-13/+30
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-König1-3/+26
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-König1-3/+26
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-König1-3/+27
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-König1-3/+26
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-König1-3/+26
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 Regno1-0/+7
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-König1-5/+5
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-König1-11/+17
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-König1-15/+35
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-König1-86/+86
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-König1-6/+38
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-König1-17/+5
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-König1-6/+3
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-König1-12/+42
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 Jiabing1-3/+2
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-König1-47/+21
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-König1-1/+1
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-König1-1/+1
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-König1-7/+34
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-König1-0/+1
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 Hsieh3-0/+244
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 Anderson3-0/+336
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>