If duty_ns is large enough multiplying it by 255 overflows and results
wrong duty cycle value being programmed. For example with 10ms duty when
period is 20ms (50%) we get

  255 * 10000000 / 20000000 = -87

because 255 * 10000000 overlows int. Whereas correct value should be

  255 * 10000000 / 20000000 = 127

Fix this by using unsigned long long as type for on_time_div and changing
integer literals to use proper type annotation.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

The base_unit calculation applies an offset of 0x2 which adds
significant error for lower frequencies and doesn't appear to be
warranted - rounding the division result gives a correct value.

Also, the upper limit check for base_unit is off-by-one; the upper
nibble of base_unit is invalid if >=128 according to the Table 88
in the Z8000 Processor Series Datasheet Volume 1 (Rev. 2).

Verified on UP Board (Cherry Trail) and Minnowboard Max (Bay Trail).
Signed-off-by: NDan O'Donovan <dan@emutex.com>
Acked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

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: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

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: NQipeng Zha <qipeng.zha@intel.com>
Acked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

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: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

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: NHuiquan Zhong <huiquan.zhong@intel.com>
Signed-off-by: NQipeng Zha <qipeng.zha@intel.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

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: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

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: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

Use c99 initializers for structures.

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

// <smpl>
@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
 ,...};
// </smpl>
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
[thierry.reding: rebased and applied same fix for Braswell]
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

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: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

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: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NAlan Cox <alan@linux.intel.com>
[thierry.reding: change select to depends on PWM_LPSS, cleanup]
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

This is pretty much the same as Baytrail PWM. Only difference is that the
input clock runs on different frequency.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

Unlike other Intel LPSS devices, the PWM does not have the
clock dividers or the gate. All we get from the clock is the
rate. Since PCI case uses the driver data to get the rate,
we can drop the clk and use the same data also in case of
ACPI. The frequency is the same.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NChew, Chiau Ee <chiau.ee.chew@intel.com>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

Fixes the following warnings reported by the 0-DAY kernel build testing
backend:

   drivers/pwm/pwm-lpss.c: In function 'pwm_lpss_probe_pci':
>> drivers/pwm/pwm-lpss.c:192:2: warning: passing argument 3 of 'pwm_lpss_probe' discards 'const' qualifier from pointer target type [enabled by default]
     lpwm = pwm_lpss_probe(&pdev->dev, &pdev->resource[0], info);
     ^
   drivers/pwm/pwm-lpss.c:130:30: note: expected 'struct pwm_lpss_boardinfo *' but argument is of type 'const struct pwm_lpss_boardinfo *'
    static struct pwm_lpss_chip *pwm_lpss_probe(struct device *dev,
                                 ^
>> drivers/pwm/pwm-lpss.c:143:28: sparse: incorrect type in return expression (different address spaces)
   drivers/pwm/pwm-lpss.c:143:28:    expected struct pwm_lpss_chip *
   drivers/pwm/pwm-lpss.c:143:28:    got void [noderef] <asn:2>*regs
>> drivers/pwm/pwm-lpss.c:192:63: sparse: incorrect type in argument 3 (different modifiers)
   drivers/pwm/pwm-lpss.c:192:63:    expected struct pwm_lpss_boardinfo *info
   drivers/pwm/pwm-lpss.c:192:63:    got struct pwm_lpss_boardinfo const *[assigned] info
   drivers/pwm/pwm-lpss.c: In function 'pwm_lpss_probe_pci':
   drivers/pwm/pwm-lpss.c:192:2: warning: passing argument 3 of 'pwm_lpss_probe' discards 'const' qualifier from pointer target type [enabled by default]
     lpwm = pwm_lpss_probe(&pdev->dev, &pdev->resource[0], info);
     ^
   drivers/pwm/pwm-lpss.c:130:30: note: expected 'struct pwm_lpss_boardinfo *' but argument is of type 'const struct pwm_lpss_boardinfo *'
    static struct pwm_lpss_chip *pwm_lpss_probe(struct device *dev,
                                 ^
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

Not all systems enumerate the PWM devices via ACPI. They can also be
exposed via the PCI interface.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NChew, Chiau Ee <chiau.ee.chew@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

Add support for Intel Low Power I/O subsystem PWM controllers found on
Intel BayTrail SoC.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NChew, Kean Ho <kean.ho.chew@intel.com>
Signed-off-by: NChang, Rebecca Swee Fun <rebecca.swee.fun.chang@intel.com>
Signed-off-by: NChew, Chiau Ee <chiau.ee.chew@intel.com>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>