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2016-03-23pwm: omap-dmtimer: Add debug message for effective period and duty cycleDavid Rivshin1-1/+8
After going through the math and constraints checking to compute load and match values, it is helpful to know what the resultant period and duty cycle are. Signed-off-by: David Rivshin <drivshin@allworx.com> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-23pwm: omap-dmtimer: Round load and match values rather than truncateDavid Rivshin1-5/+1
When converting period and duty_cycle from nanoseconds to fclk cycles, the error introduced by the integer division can be appreciable, especially in the case of slow fclk or short period. Use DIV_ROUND_CLOSEST_ULL() so that the error is kept to +/- 0.5 clock cycles. Fixes: 6604c6556db9 ("pwm: Add PWM driver for OMAP using dual-mode timers") Signed-off-by: David Rivshin <drivshin@allworx.com> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-23pwm: omap-dmtimer: Add sanity checking for load and match valuesDavid Rivshin1-4/+30
Add sanity checking to ensure that we do not program load or match values that are out of range if a user requests period or duty_cycle values which are not achievable. The match value cannot be less than the load value (but can be equal), and neither can be 0xffffffff. This means that there must be at least one fclk cycle between load and match, and another between match and overflow. Fixes: 6604c6556db9 ("pwm: Add PWM driver for OMAP using dual-mode timers") Signed-off-by: David Rivshin <drivshin@allworx.com> Acked-by: Neil Armstrong <narmstrong@baylibre.com> [thierry.reding@gmail.com: minor coding style cleanups] Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-23pwm: omap-dmtimer: Fix inaccurate period and duty cycle calculationsDavid Rivshin1-7/+20
Fix the calculation of load_value and match_value. Currently they are slightly too low, which produces a noticeably wrong PWM rate with sufficiently short periods (i.e. when 1/period approaches clk_rate/2). Example: clk_rate=32768Hz, period=122070ns, duty_cycle=61035ns (8192Hz/50% PWM) Correct values: load = 0xfffffffc, match = 0xfffffffd Current values: load = 0xfffffffa, match = 0xfffffffc effective PWM: period=183105ns, duty_cycle=91553ns (5461Hz/50% PWM) Fixes: 6604c6556db9 ("pwm: Add PWM driver for OMAP using dual-mode timers") Signed-off-by: David Rivshin <drivshin@allworx.com> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Tested-by: Adam Ford <aford173@gmail.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-23pwm: brcmstb: Fix check of devm_ioremap_resource() return codeVladimir Zapolskiy1-2/+2
The change fixes potential oops while accessing iomem on invalid address if devm_ioremap_resource() fails due to some reason. The devm_ioremap_resource() function returns ERR_PTR() and never returns NULL, which makes useless a following check for NULL. Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Fixes: 3a9f5957020f ("pwm: Add Broadcom BCM7038 PWM controller support") Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-23pwm: rcar: Depend on ARCH_RENESAS instead of ARCH_SHMOBILESimon Horman1-1/+1
This is part of an ongoing process to migrate from ARCH_SHMOBILE to ARCH_RENESAS the motivation for which being that RENESAS seems to be a more appropriate name than SHMOBILE for the majority of Renesas ARM based SoCs. Signed-off-by: Simon Horman <horms+renesas@verge.net.au> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-23pwm: lpc18xx-sct: Test clock rate to avoid division by 0Wolfram Sang1-0/+5
The clk API may return 0 on clk_get_rate(), so we should check the result before using it as a divisor. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Joachim Eastwood <manabian@gmail.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-23pwm: img: Test clock rate to avoid division by 0Wolfram Sang1-0/+5
The clk API may return 0 on clk_get_rate(), so we should check the result before using it as a divisor. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-01-21pwm: Mark all devices as "might sleep"Thierry Reding1-1/+1
Commit d1cd21427747 ("pwm: Set enable state properly on failed call to enable") introduced a mutex that is needed to protect internal state of PWM devices. Since that mutex is acquired in pwm_set_polarity() and in pwm_enable() and might potentially block, all PWM devices effectively become "might sleep". It's rather pointless to keep the .can_sleep field around, but given that there are external users let's postpone the removal for the next release cycle. Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-01-04pwm: omap-dmtimer: Potential NULL dereference on errorDan Carpenter1-1/+1
"omap" is NULL so we can't dereference it. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-01-04pwm: add HAS_IOMEM dependency to PWM_FSL_FTMVegard Nossum1-0/+1
Ran into this on UML: drivers/built-in.o: In function `fsl_pwm_probe': linux/drivers/pwm/pwm-fsl-ftm.c:436: undefined reference to `devm_ioremap_resource' collect2: error: ld returned 1 exit status devm_ioremap_resource() is defined only when HAS_IOMEM is selected. Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Cc: Xiubo Li <Li.Xiubo@freescale.com> Cc: Alison Wang <b18965@freescale.com> Cc: Jingchang Lu <b35083@freescale.com> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Yuan Yao <yao.yuan@freescale.com> Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-12-16pwm: Add PWM driver for OMAP using dual-mode timersNeil Armstrong3-0/+337
Adds support for using a OMAP dual-mode timer with PWM capability as a Linux PWM device. The driver controls the timer by using the dmtimer API. Add a platform_data structure for each pwm-omap-dmtimer nodes containing the dmtimers functions in order to get driver not rely on platform specific functions. Cc: Grant Erickson <marathon96@gmail.com> Cc: NeilBrown <neilb@suse.de> Cc: Joachim Eastwood <manabian@gmail.com> Suggested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Acked-by: Tony Lindgren <tony@atomide.com> [thierry.reding@gmail.com: coding style bikeshed, fix timer leak] Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-12-16pwm: rcar: Improve accuracy of frequency division settingRyo Kodama1-1/+1
From: Ryo Kodama <ryo.kodama.vz@renesas.com> When period_ns is set to the same value of RCAR_PWM_MAX_CYCLE in rcar_pwm_get_clock_division(), this function should allow such value for improving accuracy of frequency division setting. Signed-off-by: Ryo Kodama <ryo.kodama.vz@renesas.com> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-12-16pwm: lpc32xx: return ERANGE, if requested period is not supportedVladimir Zapolskiy1-3/+3
Instead of silent acceptance of unsupported requested configuration for PWM period and setting the boundary supported value, return -ERANGE to a caller. Duty period value equal to 0 or period is still accepted to allow configuration by PWM sysfs interface, when it is set to 0 by default. For reference this is a list of restrictions on period_ns == 1/freq: | PWM parent clock | parent clock divisor | max freq | min freq | +------------------+----------------------+----------+----------+ | HCLK == 13 MHz | 1 (min) | 50.7 KHz | 198.3 Hz | | HCLK == 13 MHz | 15 (max) | 3.38 KHz | 13.22 Hz | | RTC == 32.7 KHz | 1 (min) | 128 Hz | 0.5 Hz | | RTC == 32.7 KHz | 15 (max) | 8.533 Hz | 0.033 Hz | Note that PWM sysfs interface does not support setting of period more than NSEC_PER_SEC / MAX_INT32 ~ 2 seconds, however this PWM controller supports a period up to 30 seconds. Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-12-16pwm: lpc32xx: fix and simplify duty cycle and period calculationsVladimir Zapolskiy1-34/+19
The change fixes a problem, if duty_ns is too small in comparison to period_ns (as a valid corner case duty_ns is 0 ns), then due to PWM_DUTY() macro applied on a value the result is overflowed over 8 bits, and instead of the highest bitfield duty cycle value 0xff the invalid duty cycle bitfield value 0x00 is written. For reference the LPC32xx spec defines PWMx_DUTY bitfield description is this way and it seems to be correct: [Low]/[High] = [PWM_DUTY]/[256-PWM_DUTY], where 0 < PWM_DUTY <= 255. In addition according to my oscilloscope measurements LPC32xx PWM is "tristate" in sense that it produces a wave with floating min/max voltage levels for different duty cycle values, for corner cases: PWM_DUTY == 0x01 => signal is in range from -1.05v to 0v .... PWM_DUTY == 0x80 => signal is in range from -0.75v to +0.75v .... PWM_DUTY == 0xff => signal is in range from 0v to +1.05v PWM_DUTY == 0x00 => signal is around 0v, PWM is off Due to this peculiarity on very long period ranges (less than 1KHz) and odd pre-divider values PWM generated wave does not remind a clock shape signal, but rather a heartbit shape signal with positive and negative peaks, so I would recommend to use high-speed HCLK clock as a PWM parent clock and avoid using RTC clock as a parent. The change corrects PWM output in corner cases and prevents any possible overflows in calculation of values for PWM_DUTY and PWM_RELOADV bitfields, thus helper macro definitions may be removed. Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-12-16pwm: lpc32xx: make device usable with common clock frameworkVladimir Zapolskiy1-2/+2
As a preparatory change for switching LPC32xx mach support to common clock framework fix clk_enable/clk_disable calls without matching clk_prepare/clk_unprepare. The driver can not be used on a platform with common clock framework until clk_prepare/clk_unprepare calls are added, otherwise clk_enable calls will fail and a WARN is generated: # echo 1 > /sys/bus/platform/drivers/lpc32xx-pwm/4005c000.pwm/pwm/pwmchip0/pwm0/enable ------------[ cut here ]------------ WARNING: CPU: 0 PID: 701 at drivers/clk/clk.c:727 clk_core_enable+0x2c/0xa4() Modules linked in: sc16is7xx CPU: 0 PID: 701 Comm: sh Tainted: G W 4.3.0-rc2+ #171 Hardware name: LPC32XX SoC (Flattened Device Tree) Backtrace: [<>] (dump_backtrace) from [<>] (show_stack+0x18/0x1c) [<>] (show_stack) from [<>] (dump_stack+0x20/0x28) [<>] (dump_stack) from [<>] (warn_slowpath_common+0x90/0xb8) [<>] (warn_slowpath_common) from [<>] (warn_slowpath_null+0x24/0x2c) [<>] (warn_slowpath_null) from [<>] (clk_core_enable+0x2c/0xa4) [<>] (clk_core_enable) from [<>] (clk_enable+0x24/0x38) [<>] (clk_enable) from [<>] (lpc32xx_pwm_enable+0x1c/0x40) [<>] (lpc32xx_pwm_enable) from [<>] (pwm_enable+0x48/0x5c) [<>] (pwm_enable) from [<>] (pwm_enable_store+0x5c/0x78) [<>] (pwm_enable_store) from [<>] (dev_attr_store+0x20/0x2c) [<>] (dev_attr_store) from [<>] (sysfs_kf_write+0x44/0x50) [<>] (sysfs_kf_write) from [<>] (kernfs_fop_write+0x134/0x194) [<>] (kernfs_fop_write) from [<>] (__vfs_write+0x34/0xdc) [<>] (__vfs_write) from [<>] (vfs_write+0xb8/0x140) [<>] (vfs_write) from [<>] (SyS_write+0x50/0x90) [<>] (SyS_write) from [<>] (ret_fast_syscall+0x0/0x38) Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-12-16pwm: lpc32xx: correct number of PWM channels from 2 to 1Vladimir Zapolskiy1-1/+1
LPC32xx SoC has two independent PWM controllers, they have different clock parents, clock gates and even slightly different controls, and each of these two PWM controllers has one output channel. Due to almost similar controls arranged in a row it is incorrectly set that there is one PWM controller with two channels, fix this problem, which at the moment prevents separate configuration of different clock parents and gates for both PWM controllers. The change makes previous PWM device node description incompatible with this update. Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-12-16pwm: fsl-ftm: Fix clock enable/disable when using PMStefan Agner1-33/+25
A FTM PWM instance enables/disables three clocks: The bus clock, the counter clock and the PWM clock. The bus clock gets enabled on pwm_request, whereas the counter and PWM clocks will be enabled upon pwm_enable. The driver has three closesly related issues when enabling/disabling clocks during suspend/resume: - The three clocks are not treated differently in regards to the individual PWM state enabled/requested. This can lead to clocks getting disabled which have not been enabled in the first place (a PWM channel which only has been requested going through suspend/resume). - When entering suspend, the current behavior relies on the FTM_OUTMASK register: If a PWM output is unmasked, the driver assumes the clocks are enabled. However, some PWM instances have only 2 channels connected (e.g. Vybrid's FTM1). In that case, the FTM_OUTMASK reads 0x3 if all channels are disabled, even if the code wrote 0xff to it before. For those PWM instances, the current approach to detect enabled PWM signals does not work. - A third issue applies to the bus clock only, which can get enabled multiple times (once for each PWM channel of a PWM chip). This is fine, however when entering suspend mode, the clock only gets disabled once. This change introduces a different approach by relying on the enable and prepared counters of the clock framework and using the frameworks PWM signal states to address all three issues. Clocks get disabled during suspend and back enabled on resume regarding to the PWM channels individual state (requested/enabled). Since we do not count the clock enables in the driver, this change no longer clears the Status and Control registers Clock Source Selection (FTM_SC[CLKS]). However, since we disable the selected clock anyway, and we explicitly select the clock source on reenabling a PWM channel this approach should not make a difference in practice. Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-12-16pwm: lpss: Rework the sequence of programming PWM_SW_UPDATEMika Westerberg1-2/+21
Setting of PWM_SW_UPDATE is bit different in Intel Broxton compared to the previous generation SoCs. Previously it was OK to set the bit many times (from userspace via sysfs for example) before the PWM is actually enabled. Starting from Intel Broxton it seems that we must set PWM_SW_UPDATE only once before the PWM is enabled. Otherwise it is possible that the PWM does not start properly. Change the sequence of how PWM_SW_UPDATE is programmed so that we only set it in pwm_lpss_config() when the PWM is already enabled. The initial setting of PWM_SW_UPDATE will be done when PWM gets enabled. This should make the driver work with the previous generation Intel SoCs and Broxton. Add also small delay after the bit is set to let the hardware propagate it properly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-12-16pwm: lpss: Select core part automaticallyAndy Shevchenko1-10/+5
We have two users of core part right now. Let them to select core part automatically. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-12-16pwm: lpss: Update PWM setting for Broxtonqipeng.zha2-14/+20
For Broxton PWM controller, base unit is defined as 8-bit integer and 14-bit fraction, so need to update base unit setting to output wave with right frequency. Signed-off-by: Qipeng Zha <qipeng.zha@intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-12-16pwm: bcm2835: Fix email address specificationStefan Wahren1-1/+1
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-12-16pwm: bcm2835: Prevent division by zeroStefan Wahren1-1/+9
It's possible that the PWM clock becomes an orphan. So better check the result of clk_get_rate() in order to prevent a division by zero. Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-12-16pwm: bcm2835: Calculate scaler in ->config()Stefan Wahren1-5/+3
Currently pwm-bcm2835 assumes a fixed clock rate and stores the resulting scaler in the driver structure. But with the upcoming PWM clock support for clk-bcm2835 the rate could change, so calculate the scaler in the ->config() callback. Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-12-16pwm: lpss: Remove ->free() callbackMika Westerberg1-1/+0
The LPSS PWM driver calls pwm_lpss_disable() when the PWM device is released (for example unexported from sysfs). This in turn calls pm_runtime_put() which makes runtime PM count to be unbalanced if the device has not been enabled at this point. This is easy to reproduce: # cd /sys/class/pwm/pwmchip0 # echo 0 > export # echo 0 > unexport The count is unbalanced and prevents the PWM device from being powered on next time. Fix this by removing ->free() callback. There are no resources to be released anyway. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-11-11Merge tag 'pwm/for-4.4-rc1' of ↵Linus Torvalds15-80/+1323
git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm Pull pwm updates from Thierry Reding: "This round contains a couple of new drivers for the Marvell Berlin family of SoCs, various SoCs from Renesas and Broadcom as well as the backlight PWM present on MediaTek SoCs. Further existing drivers are extended to support a wider range of hardware. The remaining patches are minor fixes and cleanups across the board. Note that one of the patches included in this pull request is against arch/unicore32. I've included it here because I couldn't get a response from Guan Xuetao and I consider the change low-risk. Equivalent patches have been merged and tested in Samsung and PXA trees. The goal is to finally get rid of legacy code paths that have repeatedly been causing headaches" * tag 'pwm/for-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: (24 commits) pwm: sunxi: Fix whitespace issue pwm: sysfs: Make use of the DEVICE_ATTR_[RW][WO] macro's pwm: sysfs: Remove unnecessary temporary variable unicore32: nb0916: Use PWM lookup table pwm: pwm-rcar: Revise the device tree binding document about compatible pwm: Return -ENODEV if no PWM lookup match is found pwm: sun4i: Add support for PWM controller on sun5i SoCs pwm: Set enable state properly on failed call to enable pwm: lpss: Add support for runtime PM pwm: lpss: Add more Intel Broxton IDs pwm: lpss: Support all four PWMs on Intel Broxton pwm: lpss: Add support for multiple PWMs pwm-pca9685: enable ACPI device found on Galileo Gen2 pwm: Add MediaTek display PWM driver support dt-bindings: pwm: Add MediaTek display PWM bindings pwm: tipwmss: Enable on TI DRA7x and AM437x pwm: atmel-hlcdc: add sama5d2 SoC support. pwm: Add Broadcom BCM7038 PWM controller support Documentation: dt: add Broadcom BCM7038 PWM controller binding pwm: Add support for R-Car PWM Timer ...
2015-11-10pwm: sunxi: Fix whitespace issueOlliver Schinagl1-1/+1
This patch changes no code, it just fixes the whitespacing. Operators should be separated from operands by a single space. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-11-10pwm: sysfs: Make use of the DEVICE_ATTR_[RW][WO] macro'sOlliver Schinagl1-36/+36
For the npwm property the PWM sysfs interface already made use of the DEVICE_ATTR_RO macro. This patch expands this to the other sysfs properties so that the code base is concise and makes use of this helpful macro. This has the advantage of slightly reducing the code size, improving readability and no longer using magic values for permissions. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-11-10pwm: sysfs: Remove unnecessary temporary variableOlliver Schinagl1-2/+1
Use the result of pwm_is_enabled() directly instead of storing it in a temporary variable. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-11-10pwm: Return -ENODEV if no PWM lookup match is foundThierry Reding1-1/+3
When looking up a PWM using the lookup table, assume that all entries will have been added already, so failure to find a match means that no corresponding entry has been registered. This fixes an issue where -EPROBE_DEFER would be returned if the PWM lookup table is empty. After this fix, -EPROBE_DEFER is reserved for situations where no provider has yet registered for a matching entry. Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-11-10pwm: sun4i: Add support for PWM controller on sun5i SoCsHans de Goede1-2/+23
The PWM controller on sun5i SoCs is identical to the one found on sun7i SoCs. On the A13 package only one of the 2 pins is routed to the outside, so only advertise one PWM channel there. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-11-10pwm: Set enable state properly on failed call to enableJonathan Richardson1-7/+26
The pwm_enable() function didn't clear the enabled bit if a call to the driver's ->enable() callback returned an error. The result was that the state of the PWM core was wrong. Clearing the bit when enable returns an error ensures the state is properly set. Tested-by: Jonathan Richardson <jonathar@broadcom.com> Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Jonathan Richardson <jonathar@broadcom.com> [thierry.reding@gmail.com: add missing kerneldoc for the lock] Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-11-06pwm: lpss: Add support for runtime PMQipeng Zha3-0/+45
To be able to save some power when PWM is not in use, add support for runtime PM for this driver. This also allows the platform to transition to low power S0ix states when the system is idle. Signed-off-by: Huiquan Zhong <huiquan.zhong@intel.com> Signed-off-by: Qipeng Zha <qipeng.zha@intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-11-06pwm: lpss: Add more Intel Broxton IDsMika Westerberg2-0/+2
Add more Intel Broxton ACPI and PCI IDs to the driver supported devices list. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-11-06pwm: lpss: Support all four PWMs on Intel BroxtonMika Westerberg3-2/+10
Intel Broxton has similar PWM than Intel Braswell but instead of one it has four PWMs included in one PCI/ACPI device. This patch adds support for all the four PWMs and changes the PCI part of the driver to use 'pwm_lpss_bxt_info' instead. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-11-06pwm: lpss: Add support for multiple PWMsMika Westerberg2-21/+28
New Intel SoCs such as Broxton will have four PWMs per PCI (or ACPI) device. Each PWM has 1k of register space allocated from the parent device. Add support for this. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-11-06pwm-pca9685: enable ACPI device found on Galileo Gen2Andy Shevchenko2-5/+17
There is a chip connected to i2c bus on Intel Galileo Gen2 board. Enable it via ACPI ID INT3492. Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-06pwm: Add MediaTek display PWM driver supportYH Huang3-0/+255
Add display PWM driver support to modify backlight for MT8173 and MT6595. The PWM has one channel to control the brightness of the display. When the (high_width / period) is closer to 1, the screen is brighter; otherwise, it is darker. Signed-off-by: YH Huang <yh.huang@mediatek.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-06pwm: tipwmss: Enable on TI DRA7x and AM437xVignesh R1-3/+3
TIPWMSS is present on TI's DRA7x and AM437x SoCs. Enable its usage. Instead of adding each SoC individually, use the more generic symbol ARCH_OMAP2PLUS instead. Signed-off-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Sekhar Nori <nsekhar@ti.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-06pwm: atmel-hlcdc: add sama5d2 SoC support.Nicolas Ferre1-0/+3
Add sama5d2 hlcdc backlight PWM support. This chip doesn't have to deal with an errata, so it's a simple addition of the mfd compatible string. Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-06pwm: Add Broadcom BCM7038 PWM controller supportFlorian Fainelli3-0/+354
Add support for the BCM7038-style PWM controller found in all BCM7xxx STB SoCs. This controller has a hardcoded 2 channels per controller, and cascades a variable frequency generator on top of a fixed frequency generator which offers a range of a 148ns period all the way to ~622ms periods. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-06misc: atmel_tclib: get and use slow clockBoris Brezillon1-7/+19
Commit dca1a4b5ff6e ("clk: at91: keep slow clk enabled to prevent system hang") added a workaround for the slow clock as it is not properly handled by its users. Get and use the slow clock as it is necessary for the timer counters. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-06pwm: Add support for R-Car PWM TimerYoshihiro Shimoda3-0/+286
This patch adds support for R-Car SoCs PWM Timer. The PWM timer of R-Car H2 has 7 channels. So, we can use the channels if we describe device tree nodes. Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-06pwm: Add support for the Berlin PWM controllerAntoine Ténart3-0/+229
Add a PWM controller driver for the Marvell Berlin SoCs. This PWM controller has 4 channels. Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com> Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-09-21pwm: atmel-hlcdc: Fix module autoload for OF platform driverLuis de Bethencourt1-0/+1
This platform driver has a OF device ID table but the OF module alias information is not created so module autoloading won't work. This patch adds the missing MODULE_DEVICE_TABLE() for OF to export that information so modules have the correct aliases built-in and autoloading works correctly. A longer explanation by Javier Canillas can be found here: https://lkml.org/lkml/2015/7/30/519 Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-09-09Merge tag 'pwm/for-4.3-rc1' of ↵Linus Torvalds18-55/+697
git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm Pull pwm updates from Thierry Reding: "This set of changes introduces the beginnings of a new API that's based around the concept of states that can be atomically applied. Drivers go to various lengths to implement something similar, which indicates that the core should really be providing the necessary framework. On top of that, there is a bit of cleanup as well as improved kerneldoc and integration into the device-drivers DocBook. Regarding drivers there is a new one for the NXP LPC18xx family of SoCs and a couple of fixes for existing drivers (pca9685, Broadcom Kona and Atmel HLCDC)" * tag 'pwm/for-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: ARM: at91: pwm: atmel-hlcdc: Add at91sam9n12 errata pwm: Add NXP LPC18xx PWM/SCT DT binding documentation pwm: NXP LPC18xx PWM/SCT driver pwm-pca9685: Support changing the output frequency pwm-pca9685: Fix several driver bugs pwm: kona: Modify settings application sequence pwm: pca9685: Drop owner assignment pwm: Add to device-drivers documentation pwm: Clean up kerneldoc pwm: Remove useless whitespace pwm: sysfs: Remove unnecessary padding pwm: sysfs: Properly convert from enum to string pwm: Make use of pwm_get_xxx() helpers where appropriate pwm: Add pwm_get_polarity() helper function pwm: Constify PWM device where possible pwm: Add the pwm_is_enabled() helper
2015-09-09ARM: at91: pwm: atmel-hlcdc: Add at91sam9n12 errataJosh Wu1-0/+5
The errata for HLCDC PWM of at91sam9n12 are the same as for at91sam9x5. Signed-off-by: Josh Wu <josh.wu@atmel.com> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-09-09pwm: NXP LPC18xx PWM/SCT driverAriel D'Alessandro3-0/+478
This commit adds support for NXP LPC18xx PWM/SCT. NXP LPC SoCs family, which includes LPC18xx/LPC43xx, provides a State Configurable Timer (SCT) which can be configured as a Pulse Width Modulator. Other SoCs in that family may share the same hardware. The PWM supports a total of 16 channels, but only 15 can be simultaneously requested. There's only one period, global to all the channels, thus PWM driver will refuse setting different values to it, unless there's only one channel requested. Signed-off-by: Ariel D'Alessandro <ariel@vanguardiasur.com.ar> [thierry.reding@gmail.com: remove excessive padding of fields] Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-08-17pwm-pca9685: Support changing the output frequencyClemens Gruber1-1/+64
Previously, period_ns and duty_ns were only used to determine the ratio of ON and OFF time, the default frequency of 200 Hz was never changed. The PCA9685 however is capable of changing the PWM output frequency, which is expected when changing the period. This patch configures the prescaler accordingly, using the formula and notes provided in the PCA9685 datasheet. Bounds checking for the minimum and maximum frequencies, last updated in revision v.4 of said datasheet, is also added. The prescaler is only touched if the period changed, because we have to put the chip into sleep mode to unlock the prescale register. If it is changed, the PWM output frequency changes for all outputs, because there is one prescaler per chip. This is documented in the PCA9685 datasheet and in the comments. If the duty cycle is not changed at the same time as the period, then we restart the PWM output using the duty cycle to period ratio from before the period change. When using LEDs for example, previously set brightness levels stay the same when the frequency changes. Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Steffen Trumtrar <s.trumtrar@pengutronix.de> Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-08-17pwm-pca9685: Fix several driver bugsClemens Gruber1-0/+24
Problems: - When duty_ns == period_ns, the full OFF bit was not cleared and the PWM output of the PCA9685 stayed off. - When duty_ns == period_ns and the catch-all channel was used, the ALL_LED_OFF_L register was not cleared. - The full ON bit was not cleared when setting the OFF time, therefore the exact OFF time was ignored when setting a duty_ns < period_ns Solution: Clear both OFF registers when setting full ON and clear the full ON bit when changing the OFF registers. Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Steffen Trumtrar <s.trumtrar@pengutronix.de> Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
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