Eric Lee / smarc-fsl-linux-kernel

19 May, 2015

1 commit

  • 1e70897d0   pwm: img: Impose upper and lower timebase steps value ... Browse Code »

    The PWM hardware on Pistachio platform has a maximum timebase steps
    value to 255. To fix it, let's introduce a compatible-specific
    data structure to contain the SoC-specific details and use it to
    specify a maximum timebase.

    Also, let's limit the minimum timebase to 16 steps, to allow a sane
    range of duty cycle steps.

    Fixes: 277bb6a29e00 ("pwm: Imagination Technologies PWM DAC driver")
    Signed-off-by: Naidu Tellapati
    Signed-off-by: Ezequiel Garcia
    Signed-off-by: Thierry Reding

    Naidu Tellapati
     

23 Apr, 2015

1 commit

  • c264f1110   pwm: Remove __init initializer for pwm_add_table() ... Browse Code »

    For platforms that don't support DT, some early MFD modules can register
    lookup tables. Remove the __init annotation so that this works. This is
    similar to gpio_add_lookup_table() which allows late additions.

    CC: Samuel Ortiz
    Cc: Linus Walleij
    Cc: Alexandre Courbot
    Cc: Thierry Reding
    Signed-off-by: Shobhit Kumar
    Signed-off-by: Thierry Reding

    Shobhit Kumar
     

27 Mar, 2015

1 commit

  • 4a1c683c9   pwm: samsung: Fix output race on disabling ... Browse Code »

    When disabling the Samsung PWM the output state remains at the level it
    was at the end of a PWM cycle. In other words, calling pwm_disable()
    when at 100% duty cycle will keep the output active, while at all other
    settings the output will go/stay inactive. On top of that the Samsung
    PWM settings are double-buffered, which means the new settings only get
    applied at the start of a new PWM cycle.

    This results in a race if the PWM is at 100% duty cycle and a driver
    calls:

    pwm_config(pwm, 0, period);
    pwm_disable(pwm);

    In this case the PWMs output will unexpectedly stay active, unless a new
    PWM cycle happened to start between the register writes in pwm_config()
    and pwm_disable(). As far as I can tell this is a regression introduced
    by 3bdf878, before that a call to pwm_config() would call
    pwm_samsung_enable() which, while heavy-handed, made sure the expected
    settings were live.

    To resolve this, while not re-introducing the issues 3bdf878 (flickering
    as the PWM got reset while in a PWM cycle) fixed, only force an update
    of the settings when at 100% duty cycle, which shouldn't have any
    noticeable effect on the output but is enough to ensure the behaviour is
    as expected on disable.

    Signed-off-by: Sjoerd Simons
    Reviewed-by: Javier Martinez Canillas
    Acked-by: Lukasz Majewski
    Signed-off-by: Thierry Reding

    Sjoerd Simons
     

11 Mar, 2015

3 commits

  • 24ccea1ce   pwm: mxs: Fix period divider computation ... Browse Code »

    The driver computes which clock divider it sould be using from the
    requested period. This computation assumes that the link between the
    register value and the actual divider value is raising 2 to the power of
    the registry value.

    div = 1 << regvalue

    This is true only for the first 5 values out of 8. Next values are 64,
    256 and, 1024 - instead of 32, 64, 128.
    This affects only the users requesting a period > 0.04369s.

    Replace the computation with a look-up table.

    Signed-off-by: Gaetan Hug
    Acked-by: Shawn Guo
    Signed-off-by: Thierry Reding

    Gaetan Hug
     
  • 054d3e1f9   pwm: atmel-hlcdc: Add errata handling for sama5d4 ... Browse Code »

    sama5d4 SoC also has an errata on the HLCDC PWM. It is the same as the
    sama5d3 that is forbidding the use of div1 prescaler.

    Signed-off-by: Nicolas Ferre
    Acked-by: Boris Brezillon
    Signed-off-by: Thierry Reding

    Nicolas Ferre
     
  • c456fbb2b   pwm: pca9685: Constify struct regmap_config ... Browse Code »

    The regmap_config struct may be const because it is not modified by the
    driver and regmap_init() accepts pointer to const.

    Signed-off-by: Krzysztof Kozlowski
    Signed-off-by: Thierry Reding

    Krzysztof Kozlowski
     

18 Feb, 2015

1 commit

03 Feb, 2015

1 commit

30 Jan, 2015

5 commits

  • 277bb6a29   pwm: Imagination Technologies PWM DAC driver ... Browse Code »

    The Pistachio SOC from Imagination Technologies includes a Pulse Width
    Modulation DAC which produces 1 to 4 digital bit-outputs which represent
    digital waveforms. These PWM outputs are primarily in charge of controlling
    backlight LED devices.

    Reviewed-by: Andrew Bresticker
    Signed-off-by: Naidu Tellapati
    Signed-off-by: Sai Masarapu
    Signed-off-by: Ezequiel Garcia
    Reviewed-by: Vladimir Zapolskiy
    [thierry.reding: fixup license header as discussed on list]
    Signed-off-by: Thierry Reding

    Naidu Tellapati
     
  • cd264b6a6   pwm: sti: Maintain a bitmap of configured devices ... Browse Code »

    This patch introduces a bitmap which is used to keep track of the
    pwm channels which have been configured in a pwm chip.

    The method used earlier to find the number of configured channels,
    was to count the pwmdevices with PWMF_REQUESTED field set
    and period value configured. This was not correct and failed
    when of_pwm_get()/pwm_get() and then pwm_config() was used.

    Signed-off-by: Ajit Pal Singh
    Signed-off-by: Thierry Reding

    Ajit Pal Singh
     
  • 09853ce7b   pwm: Add Allwinner SoC support ... Browse Code »

    This adds a generic PWM framework driver for the PWM controller
    found on Allwinner SoCs.

    Signed-off-by: Alexandre Belloni
    Acked-by: Maxime Ripard
    Signed-off-by: Thierry Reding

    Alexandre Belloni
     
  • df6922ade   pwm: atmel-hlcdc: Prevent division by zero ... Browse Code »

    The slow and system clock should never return a rate of zero, but this
    might happen if the clocks property defined in the DT is referencing the
    wrong clocks.

    Prevent any division by zero from happening by testing the clk_freq
    value before calling do_div().

    Signed-off-by: Boris Brezillon
    Signed-off-by: Thierry Reding

    Boris BREZILLON
     
  • d2048c491   pwm: atmel-hlcdc: Depend on HAVE_CLK ... Browse Code »

    The include/linux/clk.h header defines dummy implementations for the
    various clk_*() functions if HAVE_CLK is not selected to improve build
    coverage in randconfig builds.

    The dummy implementation of clk_get_rate() returns 0, which causes the
    Atmel HLCDC PWM driver's atmel_hlcdc_pwm_config() implementation to end
    up calling:

    do_div(clk_period_ns, 0)

    On x86, do_div(n, base) will end up evaluating to this:

    n >>= ilog2(base)

    with base = 0, the implementation of ilog2() will call ____ilog2_NaN(),
    which is purposely undefined and results in a linker failure:

    ERROR: "____ilog2_NaN" [drivers/pwm/pwm-atmel-hlcdc.ko] undefined!

    The implementation of do_div() checks that base is a power of 2 before
    calling ilog2(). The compiler doesn't optimize this away, presumably
    because is_power_of_2() is an inline function and the compiler doesn't
    or can't inspect it closely enough. ilog2() being a macro it still ends
    up generating the ____ilog2_NaN() because of the constant 0.

    The root of the problem is that the driver really should be checking
    before possibly dividing by zero. That should eventually be fixed, but
    for now just assume that the clock runs at a sensible frequency when
    available.

    Reported-by: Jim Davis
    Acked-by: Boris Brezillon
    Signed-off-by: Thierry Reding

    Thierry Reding
     

18 Dec, 2014

1 commit

  • 0b4954c46   Merge tag 'pwm/for-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/th… ... Browse Code »

    …ierry.reding/linux-pwm

    Pull pwm updates from Thierry Reding:
    "There are two new drivers, one for the BCM2835 (Raspberry Pi) and one
    used in conjunction with the LCD controller on various Atmel SoCs.
    The Samsung PWM driver can now be built for 64-bit ARM (Exynos7).

    A couple of fixes have been applied to the FTM PWM driver and system
    sleep support was added"

    * tag 'pwm/for-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
    pwm: atmel-hlcdc: add at91sam9x5 and sama5d3 errata handling
    pwm: ftm: Add Power Management support for FTM PWM
    pwm: ftm: Add regmap rbtree type cache support
    pwm: ftm: Correctly track usage count
    pwm: samsung: Allow Samsung PWM driver to be enabled on Exynos7
    pwm: add DT bindings documentation for atmel-hlcdc-pwm driver
    pwm: add support for atmel-hlcdc-pwm device
    pwm: Add BCM2835 PWM driver

    Linus Torvalds
     

04 Dec, 2014

1 commit

01 Dec, 2014

3 commits

17 Nov, 2014

3 commits

04 Nov, 2014

1 commit

21 Oct, 2014

1 commit

  • 5b9c89725   Merge tag 'pwm/for-3.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/th… ... Browse Code »

    …ierry.reding/linux-pwm

    Pull pwm changes from Thierry Reding:
    "There are no new drivers here, only a couple of fixes all over the
    place"

    * tag 'pwm/for-3.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
    pwm: Let PWM_CLPS711X depend on HAS_IOMEM
    pwm: atmel: Fix calculation of prescale value
    pwm: Fix uninitialized warnings in pwm_get()
    pwm: rockchip: Allow polarity invert on rk3288
    pwm: imx: Avoid sample FIFO overflow for i.MX PWM version2
    pwm: imx: Cleanup indentation for register definitions
    pwm: imx: Fix the macro MX3_PWMCR_PRESCALER(x) definition
    pwm: Fix possible ZERO_SIZE_PTR pointer dereferencing error.
    pwm: lpss: make it buildable only on X86
    pwm: lpss: use c99 initializers in structures
    pwm: lpss: Fix build failure on PowerPC
    pwm: lpss: pci: Move to use pcim_enable_device()
    pwm: lpss: Properly split driver to parts
    pwm: lpss: Add ACPI and PCI IDs for Intel Braswell
    pwm: fsl-ftm: Select REGMAP_MMIO
    pwm: fsl-ftm: Document 'big-endian' property
    pwm: fsl-ftm: Convert to direct regmap API usage
    pwm: fsl-ftm: Clean up the code

    Linus Torvalds
     

20 Oct, 2014

2 commits

25 Sep, 2014

1 commit

  • e2e089701   pwm: atmel: Fix calculation of prescale value ... Browse Code »

    The prescale value used for calculating the period was incremented
    afterwards, thus the resulting prescale value is by one too high.
    This resulted in a PWM frequency only half as high as requested.

    This patch moves the 64 bit division out of the prescale loop to
    correct the above issue and make the calculation more efficient.

    Signed-off-by: Nikolaus Voss
    Tested-by: Bo Shen
    Acked-by: Bo Shen
    Signed-off-by: Thierry Reding

    Nikolaus Voss
     

09 Sep, 2014

1 commit

  • c40c4028f   Merge tag 'at91-cleanup2' of git://github.com/at91linux/linux-at91 into next/cleanup ... Browse Code »

    Pull "Second batch of AT91 cleanup for 3.18" from Nicolas Ferre:
    - Timer Counter (TC) fixup and cleanup:
    - fix segmentation fault when kexec-ing a kernel by masking
    TC interrupts at shutdown and probe time
    - use modern driver model: devm_*, probe function, sanitize IRQ request

    Signed-off-by: Arnd Bergmann

    * tag 'at91-cleanup2' of git://github.com/at91linux/linux-at91:
    clocksource: tcb_clksrc: sanitize IRQ request
    ARM: at91/tclib: mask interruptions at shutdown and probe
    ARM: at91/tclib: move initialization from alloc to probe
    ARM: at91/tclib: prefer using of devm_* functions

    Arnd Bergmann
     

08 Sep, 2014

1 commit

  • 4930d247a   ARM: at91/tclib: move initialization from alloc to probe ... Browse Code »

    Move resource retrieval from atmel_tc_alloc to tc_probe to avoid lately
    reporting resource related issues when a TC block user request a TC block.

    Moreover, resources retrieval are usually done in the probe function,
    thus moving them add some consistency with other drivers.

    Initialization is done once, ie not every time a tc block is requested.
    If it fails, the device is not appended to the list of tc blocks.

    Furhermore, the device id is retrieved at probe as well, avoiding parsing
    DT every time the user requests of tc block.

    Signed-off-by: Gaël PORTAY
    Acked-by: Thierry Reding
    Acked-by: Boris Brezillon
    Signed-off-by: Nicolas Ferre

    Gaël PORTAY
     

29 Aug, 2014

1 commit

  • 70145f871   pwm: Fix uninitialized warnings in pwm_get() ... Browse Code »

    With some versions of gcc (e.g. 4.1.2):

    drivers/pwm/core.c: In function ‘pwm_get’:
    drivers/pwm/core.c:610: warning: ‘polarity’ may be used uninitialized in this function
    drivers/pwm/core.c:609: warning: ‘period’ may be used uninitialized in this function

    While these are false positives, we can get rid of them by refactoring
    the code to store a pointer to the best match, as suggested before by
    Thierry Reding. This does require moving the mutex_unlock() down.

    Fixes: d717ea73e36dd565 ("pwm: Fix period and polarity in pwm_get() for non-perfect matches")
    Signed-off-by: Geert Uytterhoeven
    Signed-off-by: Thierry Reding

    Geert Uytterhoeven
     

26 Aug, 2014

1 commit

25 Aug, 2014

6 commits

  • 137fd45ff   pwm: imx: Avoid sample FIFO overflow for i.MX PWM version2 ... Browse Code »

    The i.MX PWM version2 is embedded in several i.MX SoCs, such as i.MX27,
    i.MX51 and i.MX6SL. There is a 4-word (16 bit) sample FIFO in this IP.
    Each FIFO slot determines the duty period of a PWM waveform in one full
    cycle. The IP spec mentions that we should not write a fourth sample
    because the FIFO will become full and triggers a FIFO write error (FWE)
    which will prevent the PWM from starting once it is enabled. In order
    to avoid any sample FIFO overflow issue, this patch clears all sample
    FIFO by doing software reset in the configuration hook when the
    controller is disabled or waits for a full PWM cycle to get a
    relinquished FIFO slot when the controller is enabled and the FIFO is
    fully loaded.

    The FIFO overflow issue can be reproduced by the following commands on
    the i.MX6SL EVK platform, assuming we use PWM2 for the debug LED which
    is driven by the pin HSIC_STROBE and the maximal brightness is 255.

    echo 0 > /sys/class/leds/user/brightness
    echo 0 > /sys/class/leds/user/brightness
    echo 0 > /sys/class/leds/user/brightness
    echo 0 > /sys/class/leds/user/brightness
    echo 255 > /sys/class/leds/user/brightness

    Here, FWE happens (PWMSR register reads 0x58) and the LED can not be
    lighten.

    Another way to reproduce the FIFO overflow issue is to run this script:

    while true;
    do echo 255 > /sys/class/leds/user/brightness;
    done

    Cc: Thierry Reding
    Cc: Sascha Hauer
    Cc: Shawn Guo
    Cc: Lothar Waßmann
    Cc: linux-pwm@vger.kernel.org
    Cc: linux-arm-kernel@lists.infradead.org
    Signed-off-by: Liu Ying
    Acked-by: Shawn Guo
    Signed-off-by: Thierry Reding

    Liu Ying
     
  • 40f260c2c   pwm: imx: Cleanup indentation for register definitions ... Browse Code »

    This patch contains no logic change to cleanup indentation for register
    definitions only.

    Cc: Thierry Reding
    Cc: Sascha Hauer
    Cc: Shawn Guo
    Cc: Lothar Waßmann
    Cc: linux-pwm@vger.kernel.org
    Cc: linux-arm-kernel@lists.infradead.org
    Signed-off-by: Liu Ying
    Acked-by: Shawn Guo
    Signed-off-by: Thierry Reding

    Liu Ying
     
  • bd59bdc89   pwm: imx: Fix the macro MX3_PWMCR_PRESCALER(x) definition ... Browse Code »

    This patch adds missing parentheses around the argument of the macro
    MX3_PWMCR_PRESCALER(x) to avoid any potential macro expansion issue.

    Reported-by: Lothar Waßmann
    Cc: Thierry Reding
    Cc: Sascha Hauer
    Cc: Shawn Guo
    Cc: Lothar Waßmann
    Cc: linux-pwm@vger.kernel.org
    Cc: linux-arm-kernel@lists.infradead.org
    Signed-off-by: Liu Ying
    Acked-by: Shawn Guo
    Signed-off-by: Thierry Reding

    Liu Ying
     
  • 533acc0e8   pwm: Fix possible ZERO_SIZE_PTR pointer dereferencing error. ... Browse Code »

    Since we cannot make sure the 'chip->npwm' will always be none zero here,
    and then if either equal to zero, the kzalloc() will return ZERO_SIZE_PTR,
    which equals to ((void *)16).

    So this patch fix this with just doing the zero check before calling kzalloc().

    Signed-off-by: Xiubo Li
    Signed-off-by: Thierry Reding

    Xiubo Li
     
  • ad16202de   pwm: lpss: make it buildable only on X86 ... Browse Code »

    There is no sign of this IP block on non-x86 architectures and rather will not
    be. Thus, make this explicit by applying a direct dependency to X86.

    Signed-off-by: Andy Shevchenko
    Signed-off-by: Thierry Reding

    Andy Shevchenko
     
  • b2b7adeb2   pwm: lpss: use c99 initializers in structures ... Browse Code »

    Use c99 initializers for structures.

    A simplified version of the semantic match that finds this problem is as
    follows: (http://coccinelle.lip6.fr/)

    //
    @decl@
    identifier i1,fld;
    type T;
    field list[n] fs;
    @@

    struct i1 {
    fs
    T fld;
    ...};

    @bad@
    identifier decl.i1,i2;
    expression e;
    initializer list[decl.n] is;
    @@

    struct i1 i2 = { is,
    + .fld = e
    - e
    ,...};
    //

    Signed-off-by: Julia Lawall
    [thierry.reding: rebased and applied same fix for Braswell]
    Signed-off-by: Thierry Reding

    Julia Lawall
     

23 Aug, 2014

3 commits

  • e0c86a3b6   pwm: lpss: Fix build failure on PowerPC ... Browse Code »

    An x86 build seems to pull in the linux/io.h include indirectly. On
    PowerPC that doesn't happen and the build breaks due to the readl() and
    writel() functions not being declared. Fix this by explicitly including
    linux/io.h.

    Reported-by: Stephen Rothwell
    Signed-off-by: Thierry Reding

    Thierry Reding
     
  • 90927fe9a   pwm: lpss: pci: Move to use pcim_enable_device() ... Browse Code »

    Let's use managed functions for this driver.

    Signed-off-by: Andy Shevchenko
    Reviewed-by: Mika Westerberg
    Signed-off-by: Thierry Reding

    Andy Shevchenko
     
  • c558e39e1   pwm: lpss: Properly split driver to parts ... Browse Code »

    The driver consists of core, PCI, and platform parts. It would be better
    to split them into separate files.

    The platform driver is now called pwm-lpss-platform. Thus, previously
    set CONFIG_PWM_LPSS=m is not enough to build it. But we are on the safe
    side since it seems no one from outside Intel is using it for now.

    While here, move to use macros module_pci_driver() and
    module_platform_driver().

    Signed-off-by: Andy Shevchenko
    Reviewed-by: Mika Westerberg
    Acked-by: Alan Cox
    [thierry.reding: change select to depends on PWM_LPSS, cleanup]
    Signed-off-by: Thierry Reding

    Andy Shevchenko
     

22 Aug, 2014

1 commit