Commit Graph

2471 Commits

Author SHA1 Message Date
Linus Torvalds 5782fd14aa RTC for 4.11
Subsystem:
  - constify rtc_class_ops structures
 
 New driver:
  - STM32
 
 Drivers:
  - armada38x: fix errata, Armada 7K/8K support
  - ds3232: fix wakeup support
  - gemini: DT support
  - m48t86: huge cleanup and platform_data removal
  - mcp795: alarm support
  - sun6i: proper oscillator handling
  - tegra: proper clock handling
  - tps65910: calibration support
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Merge tag 'rtc-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "Subsystem:
   - constify rtc_class_ops structures

 New driver:
   - STM32

 Drivers:
   - armada38x: fix errata, Armada 7K/8K support
   - ds3232: fix wakeup support
   - gemini: DT support
   - m48t86: huge cleanup and platform_data removal
   - mcp795: alarm support
   - sun6i: proper oscillator handling
   - tegra: proper clock handling
   - tps65910: calibration support"

* tag 'rtc-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (44 commits)
  rtc: ds3232: Call device_init_wakeup before device_register
  rtc: pcf2127: bulk read only date and time registers.
  rtc: armada38x: Add support for Armada 7K/8K
  rtc: armada38x: Prepare driver to manage different versions
  rtc: ds3232: Add regmap max_register definition.
  rtc: ds3232: Cleanup whitespace around register and bit definitions.
  rtc: m48t86: remove unused platform_data
  ARM: Orion5x: ts78xx: allow rtc-m48t86 to manage it's own resources
  ARM: Orion5x: ts78xx: remove RTC detection
  ARM: ep93xx: ts72xx: allow rtc-m48t86 to manage its own resources
  rtc: m48t86: verify that the RTC is actually present
  rtc: m48t86: add NVRAM support
  rtc: m48t86: allow driver to manage its resources
  rtc: m48t86: shorten register name defines
  bindings: rtc: correct wrong reference in required properties
  rtc: sun6i: Fix return value check in sun6i_rtc_clk_init()
  rtc: sun6i: extend test coverage
  rtc: sun6i: Fix compatibility with old DT binding
  rtc: snvs: add a missing write sync
  rtc: bq32000: add support to enable disable the trickle charge FET bypass
  ...
2017-02-27 19:59:21 -08:00
Phil Reid d4f6c6f15a rtc: ds3232: Call device_init_wakeup before device_register
The wakealarm attribute is currently not exposed in the sysfs interface
as the device has not been set as doing wakealarm when device_register
is called. Changing the order of the calls fixes that problem. Interrupts
are cleared in check_rtc_status prior to requesting the interrupt.

This is only set if an irq is defined. If irq registration fails then
set wakeup_capable to false. With this change the sysfs wakealarm
attribute will be left visible but it is non functional. rtcwake
still returns that the device is not enabled for wakeup.

Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-24 11:14:53 +01:00
Sean Nyekjaer 3769a375ab rtc: pcf2127: bulk read only date and time registers.
Read control registers one by one and bulk read time registers.
This fixes when the clock is read, the watchdog counter register is zeroed.

Signed-off-by: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-23 18:38:54 +01:00
Linus Torvalds 5ab356626f Pin control bulk changes for the v4.11 kernel cycle:
Core changes:
 
 - Switch the generic pin config argument from 16 to 24 bits,
   only use 8 bits for the configuration type. We might need to
   encode more information about a certain setting than we need
   to encode different generic settings.
 
 - Add a cross-talk API to the pin control GPIO back-end,
   utilizing pinctrl_gpio_set_config() from GPIO drivers that
   want to set up a certain pin configuration in the back-end.
   This also includes the .set_config() refactoring of the
   GPIO chips, so that they pass a generic configuration for
   things like debouncing and single ended (typically open
   drain). This change has also been merged in an immutable
   branch to the GPIO tree.
 
 - Take hogs with a delayed work, so that we finalize probing
   a pin controller before trying to get any hogs.
 
 - For pin controllers putting all group and function definitions
   into the device tree, we now have generic code to deal with
   this and it is used in two drivers so far.
 
 - Simplifications of the pin request conflict check.
 
 - Make dt_free_map() optional.
 
 Updates to drivers:
 
 - pinctrl-single now use the generic helpers to generate dynamic
   group and function tables from the device tree.
 
 - Texas Instruments IOdelay configuration driver add-on to
   pinctrl-single.
 
 - i.MX: use radix trees to store groups and functions, use the new
   generic group and function helpers to manage them.
 
 - Intel: add support for hardware debouncing and 1K pull-down.
   New subdriver for the Gemini Lake SoC.
 
 - Renesas SH-PFC: drive strength and bias support, CAN bus muxing,
   MSIOF, SDHI, HSCIF for r8a7796. Gyro-ADC supporton r8a7791.
 
 - Aspeed: use syscon cross-dependencies to set up related bits in
   the LPC host controller and display controller.
 
 - Aspeed: finalize G4 and G5 support. Fix mux configuration on
   GPIOs. Add banks Y, Z, AA, AB and AC.
 
 - AMD: support additional GPIO.
 
 - STM32: set this controller to strict muxing mode.
   STM32H743 MCU support.
 
 - Allwinner sunxi: deep simplifications on how to support
   subvariants of SoCs without adding to much SoC-specific data
   for each subvariant, especially for sun5i variants. New driver
   for V3s SoCs. New driver for the H5 SoC. Support A31/A31s
   variants with the new variant framework.
 
 - Mvebu: simplifications to use a MMIO and regmap abstraction.
   New subdrivers for the 98DX3236, 98DX5241 SoCs.
 
 - Samsung Exynos: delete Exynos4415 support. Add crosstalk to the
   SoC driver to access regmaps. Add infrastructure for pin-bank
   retention control. Clean out the pin retention control from
   arch/arm/mach-exynos and arch/arm/mach-s5p and put it properly
   in the Samsung pin control driver(s).
 
 - Meson: add HDMI HPD/DDC pins. Add pwm_ao_b pin.
 
 - Qualcomm: use raw spinlock variants: this makes the qualcomm
   driver realtime-safe.
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Merge tag 'pinctrl-v4.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl

Pull pin control updates from Linus Walleij:
 "Pin control bulk changes for the v4.11 kernel cycle.

  Core changes:

   - Switch the generic pin config argument from 16 to 24 bits, only use
     8 bits for the configuration type. We might need to encode more
     information about a certain setting than we need to encode
     different generic settings.

   - Add a cross-talk API to the pin control GPIO back-end, utilizing
     pinctrl_gpio_set_config() from GPIO drivers that want to set up a
     certain pin configuration in the back-end.

     This also includes the .set_config() refactoring of the GPIO chips,
     so that they pass a generic configuration for things like
     debouncing and single ended (typically open drain). This change has
     also been merged in an immutable branch to the GPIO tree.

   - Take hogs with a delayed work, so that we finalize probing a pin
     controller before trying to get any hogs.

   - For pin controllers putting all group and function definitions into
     the device tree, we now have generic code to deal with this and it
     is used in two drivers so far.

   - Simplifications of the pin request conflict check.

   - Make dt_free_map() optional.

  Updates to drivers:

   - pinctrl-single now use the generic helpers to generate dynamic
     group and function tables from the device tree.

   - Texas Instruments IOdelay configuration driver add-on to
     pinctrl-single.

   - i.MX: use radix trees to store groups and functions, use the new
     generic group and function helpers to manage them.

   - Intel: add support for hardware debouncing and 1K pull-down. New
     subdriver for the Gemini Lake SoC.

   - Renesas SH-PFC: drive strength and bias support, CAN bus muxing,
     MSIOF, SDHI, HSCIF for r8a7796. Gyro-ADC supporton r8a7791.

   - Aspeed: use syscon cross-dependencies to set up related bits in the
     LPC host controller and display controller.

   - Aspeed: finalize G4 and G5 support. Fix mux configuration on GPIOs.
     Add banks Y, Z, AA, AB and AC.

   - AMD: support additional GPIO.

   - STM32: set this controller to strict muxing mode. STM32H743 MCU
     support.

   - Allwinner sunxi: deep simplifications on how to support subvariants
     of SoCs without adding to much SoC-specific data for each
     subvariant, especially for sun5i variants. New driver for V3s SoCs.
     New driver for the H5 SoC. Support A31/A31s variants with the new
     variant framework.

   - Mvebu: simplifications to use a MMIO and regmap abstraction. New
     subdrivers for the 98DX3236, 98DX5241 SoCs.

   - Samsung Exynos: delete Exynos4415 support. Add crosstalk to the SoC
     driver to access regmaps. Add infrastructure for pin-bank retention
     control. Clean out the pin retention control from
     arch/arm/mach-exynos and arch/arm/mach-s5p and put it properly in
     the Samsung pin control driver(s).

   - Meson: add HDMI HPD/DDC pins. Add pwm_ao_b pin.

   - Qualcomm: use raw spinlock variants: this makes the qualcomm driver
     realtime-safe"

* tag 'pinctrl-v4.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (111 commits)
  pinctrl: samsung: Fix return value check in samsung_pinctrl_get_soc_data()
  pinctrl: intel: unlock on error in intel_config_set_pull()
  pinctrl: berlin: make bool drivers explicitly non-modular
  pinctrl: spear: make bool drivers explicitly non-modular
  pinctrl: mvebu: make bool drivers explicitly non-modular
  pinctrl: sunxi: make sun5i explicitly non-modular
  pinctrl: sunxi: Remove stray printk call in sun5i driver's probe function
  pinctrl: samsung: mark PM functions as __maybe_unused
  pinctrl: sunxi: Remove redundant A31s pinctrl driver
  pinctrl: sunxi: Support A31/A31s with pinctrl variants
  pinctrl: Amend bindings for STM32 pinctrl
  pinctrl: Add STM32 pinctrl driver DT bindings
  pinctrl: stm32: Add STM32H743 MCU support
  include: dt-bindings: Add STM32H7 pinctrl DT defines
  gpio: aspeed: Remove dependence on GPIOF_* macros
  pinctrl: stm32: fix bad location of gpiochip_lock_as_irq
  drivers: pinctrl: add driver for Allwinner H5 SoC
  pinctrl: intel: Add Intel Gemini Lake pin controller support
  pinctrl: intel: Add support for 1k additional pull-down
  pinctrl: intel: Add support for hardware debouncer
  ...
2017-02-21 16:34:22 -08:00
Gregory CLEMENT 34f54f579a rtc: armada38x: Add support for Armada 7K/8K
The Armada 7K/8K use the same RTC IP than the Armada 38x. However the SOC
integration differs in 2 points:
 - MBUS bridge timing initialization
 - IRQ configuration at SoC level

Moreover the Armada 7K/8K have an issue preventing to get the interrupt
from alarm 1. This commit allows to use alarm 2 for these A7K/8K but to
still use alarm 1 for the Armada 38x.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-21 23:21:30 +01:00
Gregory CLEMENT 75faea9179 rtc: armada38x: Prepare driver to manage different versions
In order to prepare the introduction of the A7K/A8K version of the RTC,
this commit introduces a new data structure. This structure allows to
handle the differences between the integration of the RTC IP in the
SoCs. It will be:
 - MBUS bridge timing initialization
 - IRQ configuration at SoC level

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-21 23:21:28 +01:00
Phil Reid 082edf0ab1 rtc: ds3232: Add regmap max_register definition.
Add the max_register  to the regmap_config definition. This allows
dumping of the device's registers via the regmap debugfs interface.

Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-21 21:34:00 +01:00
Phil Reid ca4b0a6de8 rtc: ds3232: Cleanup whitespace around register and bit definitions.
Whitespace was a combination of spaces and tabs.
Use spaces and align register / bit definitions.

Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-21 21:33:58 +01:00
H Hartley Sweeten 0500ce589a rtc: m48t86: remove unused platform_data
All users of this driver have been updated to allow the driver to
manage it's own resources and do the read/write operations internally.
The m48t86_ops are no longer used.

Remove the platform_data header and the support code in the driver.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-21 21:23:13 +01:00
H Hartley Sweeten 3ea07127d9 rtc: m48t86: verify that the RTC is actually present
The RTC is an optional feature at purchase time on some Technologic
Systems boards. Verify that it actually exists by checking if the
last two bytes of the NVRAM can be changed.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-21 18:16:31 +01:00
H Hartley Sweeten b180cf8b0b rtc: m48t86: add NVRAM support
This RTC has 114 bytes of NVRAM. Provide access to it via a binary
sysfs 'nvram' attribute file.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-12 01:08:01 +01:00
H Hartley Sweeten 8057c86d43 rtc: m48t86: allow driver to manage its resources
Allow this driver to, optionally, manage it's own resources and do the
read/write operations if the platform does not provide them.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-12 01:07:38 +01:00
H Hartley Sweeten 68b54f477f rtc: m48t86: shorten register name defines
For aesthetics. Shorten all the register names by removing '_REG' from all
of them.
This helps fix all the checkpatch.pl issues.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-12 01:06:35 +01:00
Wei Yongjun aaa65a9ce6 rtc: sun6i: Fix return value check in sun6i_rtc_clk_init()
In case of error, the function of_io_request_and_map() returns ERR_PTR()
and never returns NULL. The NULL test in the return value check should
be replaced with IS_ERR().

Fixes: 847b8bf62eb4 ("rtc: sun6i: Expose the 32kHz oscillator")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-12 00:34:31 +01:00
Alexandre Belloni 93946c49cd rtc: sun6i: extend test coverage
COMPILE_TEST was wrongly placed, move it to the "depends on" line.
Also depend on COMMON_CLK as the driver now needs it to be properly
compiled.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-01 13:55:07 +01:00
Chen-Yu Tsai 15829cf4b3 rtc: sun6i: Fix compatibility with old DT binding
Commit 847b8bf62eb4 ("rtc: sun6i: Expose the 32kHz oscillator") adds
a new clock for the rtc block with a 2 step probe mechanism. To share
the register region between both the clock and rtc instance, a static
pointer is used to keep the related data structure.

To preserve compatibility with the old binding, the data structure
should be saved as soon as the registers are mapped in, regardless
of the presence of the clock bindings, so that the rtc device can
retrieve it when it is probed.

This fixes the rtc device not probing when we use the updated driver
with an old device tree blob.

Fixes: 847b8bf62eb4 ("rtc: sun6i: Expose the 32kHz oscillator")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-01 12:44:24 +01:00
Guy Shapiro 7bb633b1a9 rtc: snvs: add a missing write sync
The clear of the LPTA_EN flag should be synced before writing to the
alarm register. Omitting this synchronization creates a race when
trying to change existing alarm.

Signed-off-by: Guy Shapiro <guy.shapiro@mobi-wize.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-01 12:44:24 +01:00
Enric Balletbo i Serra 4c466872d8 rtc: bq32000: add support to enable disable the trickle charge FET bypass
The bq32000 includes a trickle charge circuit to maintain the charge of the
backup supply when a super capacitor is used.

You can enable the charging circuit by setting 'trickle-resistor-ohms',
additionally you can set TCFE to 1 to bypass the internal diode and boost
the charge voltage of the backup supply. You might want to enable/disable
the TCFE switch from userspace (e.g when device is only connected to a
battery)

This patch introduces a new sysfs entry to enable and disable this FET
form userspace.

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-01 12:44:23 +01:00
Maxime Ripard 5dff3a3113 rtc: sun6i: Switch to devm_rtc_device_register
Now that we have a devm variant of rtc_device_register, switch to it.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-01 12:44:23 +01:00
Maxime Ripard 3855c2c3e5 rtc: sun6i: Expose the 32kHz oscillator
The RTC controls the input source of the main 32kHz oscillator in the
system, feeding it to the clock unit too.

By default, this is using an internal, very inaccurate (+/- 30%)
oscillator with a divider to make it roughly around 32kHz. This is however
quite impractical for the RTC, since our time will not be tracked properly.

Since this oscillator is an input of the main clock unit, and since that
clock unit will be probed using CLK_OF_DECLARE, we have to use it as well,
leading to a two stage probe: one to enable the clock, the other one to
enable the RTC.

There is also a slight change in the binding that is required (and should
have been from the beginning), since we'll need a phandle to the external
oscillator used on that board. We support the old binding by not allowing
to switch to the external oscillator and only using the internal one (which
was the previous behaviour) in the case where we're missing that phandle.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-01 12:44:18 +01:00
Maxime Ripard fb61bb82cb rtc: sun6i: Switch to the external oscillator
The RTC is clocked from either an internal, imprecise, oscillator or an
external one, which is usually much more accurate.

The difference perceived between the time elapsed and the time reported by
the RTC is in a 10% scale, which prevents the RTC from being useful at all.

Fortunately, the external oscillator is reported to be mandatory in the
Allwinner datasheet, so we can just switch to it.

Cc: stable@vger.kernel.org
Fixes: 9765d2d943 ("rtc: sun6i: Add sun6i RTC driver")
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-01 12:42:50 +01:00
Maxime Ripard a9422a19ce rtc: sun6i: Add some locking
Some registers have a read-modify-write access pattern that are not atomic.

Add some locking to prevent from concurrent accesses.

Cc: stable@vger.kernel.org
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-02-01 12:42:39 +01:00
Alexandre Belloni 586655d278 rtc: jz4740: make the driver buildable as a module again
By using kernel_halt() instead of machine_halt(), we can make the driver
build as a module.
However, jz4740 platforms not loading this module will not be able to power
off.

Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

Revert "rtc: jz4740: make the driver builtin only"

This reverts commit b9168c539c.
2017-01-26 23:03:21 +01:00
Mika Westerberg 58957d2edf pinctrl: Widen the generic pinconf argument from 16 to 24 bits
The current pinconf packed format allows only 16-bit argument limiting
the maximum value 65535. For most types this is enough. However,
debounce time can be in range of hundreths of milliseconds in case of
mechanical switches so we cannot represent the worst case using the
current format.

In order to support larger values change the packed format so that the
lower 8 bits are used as type which leaves 24 bits for the argument.
This allows representing values up to 16777215 and debounce times up to
16 seconds.

We also convert the existing users to use 32-bit integer when extracting
argument from the packed configuration value.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-26 15:22:32 +01:00
Maxime Ripard 3753941475 rtc: sun6i: Disable the build as a module
Since we have to provide the clock very early on, the RTC driver cannot be
built as a module. Make sure that won't happen.

Cc: stable@vger.kernel.org
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-24 18:45:29 +01:00
Linus Walleij bc7d8ebf37 rtc: gemini: Add device tree probing
This adds bindings and simple probing for the Cortina Systems Gemini
SoC RTC.

Cc: Janos Laube <janos.dev@gmail.com>
Cc: Paulius Zaleckas <paulius.zaleckas@gmail.com>
Cc: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: devicetree@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-24 18:45:05 +01:00
Amelie Delaunay 1d70ba3bfb rtc: stm32: fix comparison warnings
This patches fixes comparison between signed and unsigned values as it
could produce an incorrect result when the signed value is converted to
unsigned:

drivers/rtc/rtc-stm32.c: In function 'stm32_rtc_valid_alrm':
drivers/rtc/rtc-stm32.c:404:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  if ((((tm->tm_year > cur_year) &&
...

It also fixes comparison always true or false due to the fact that unsigned
value is compared against zero with >= or <:

drivers/rtc/rtc-stm32.c: In function 'stm32_rtc_init':
drivers/rtc/rtc-stm32.c:514:35: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]
  for (pred_a = pred_a_max; pred_a >= 0; pred_a-- ) {

drivers/rtc/rtc-stm32.c:530:44: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
     (rate - ((pred_a + 1) * (pred_s + 1)) < 0) ?

Fixes: 4e64350f42 ("rtc: add STM32 RTC driver")
Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-23 00:47:15 +01:00
Amelie Delaunay a560c52763 rtc: stm32: use 0 instead of ~PWR_CR_DBP in regmap_update_bits
Using the ~ operator on a BIT() constant results in a large 'unsigned long'
constant that won't fit into an 'unsigned int' function argument on 64-bit
architectures, resulting in a harmless build warning in x86 allmodconfig:

drivers/rtc/rtc-stm32.c: In function 'stm32_rtc_probe':
drivers/rtc/rtc-stm32.c:651:51: error: large integer implicitly truncated to unsigned type [-Werror=overflow]
  regmap_update_bits(rtc->dbp, PWR_CR, PWR_CR_DBP, ~PWR_CR_DBP);

As PWR_CR_DBP mask prevents other bits to be cleared, replace all
~PWR_CR_DBP by 0.

Fixes: 4e64350f42 ("rtc: add STM32 RTC driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-23 00:47:15 +01:00
Thierry Reding 5fa4086987 rtc: tegra: Implement clock handling
Accessing the registers of the RTC block on Tegra requires the module
clock to be enabled. This only works because the RTC module clock will
be enabled by default during early boot. However, because the clock is
unused, the CCF will disable it at late_init time. This causes the RTC
to become unusable afterwards. This can easily be reproduced by trying
to use the RTC:

	$ hwclock --rtc /dev/rtc1

This will hang the system. I ran into this by following up on a report
by Martin Michlmayr that reboot wasn't working on Tegra210 systems. It
turns out that the rtc-tegra driver's ->shutdown() implementation will
hang the CPU, because of the disabled clock, before the system can be
rebooted.

What confused me for a while is that the same driver is used on prior
Tegra generations where the hang can not be observed. However, as Peter
De Schrijver pointed out, this is because on 32-bit Tegra chips the RTC
clock is enabled by the tegra20_timer.c clocksource driver, which uses
the RTC to provide a persistent clock. This code is never enabled on
64-bit Tegra because the persistent clock infrastructure does not exist
on 64-bit ARM.

The proper fix for this is to add proper clock handling to the RTC
driver in order to ensure that the clock is enabled when the driver
requires it. All device trees contain the clock already, therefore
no additional changes are required.

Reported-by: Martin Michlmayr <tbm@cyrius.com>
Acked-By Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-23 00:46:55 +01:00
Thierry Reding 0ae20595e3 rtc: tegra: Sort includes alphabetically
The ordering of includes is currently completely arbitrary, making it
impossible to decide where to put new includes. Remove the dilemma by
sort the include list alphabetically.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-13 17:51:59 +01:00
Arnd Bergmann 224763ef72 rtc: stm32: fix building without CONFIG_OF
The new driver has a stray #ifdef in it that causes a build error:

drivers/rtc/rtc-stm32.c:718:21: error: 'stm32_rtc_of_match' undeclared here (not in a function); did you mean 'stm32_rtc_pm_ops'?

As the #ifdef serves no purpose here, let's just remove it.

Fixes: 4e64350f42 ("rtc: add STM32 RTC driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-13 17:51:53 +01:00
Arnd Bergmann 0404abb221 rtc: stm32: remove __exit annotation on remove callback
The remove function can be called at runtime for a manual 'unbind'
operation and must not be left out from a built-in driver, as kbuild
complains:

`stm32_rtc_remove' referenced in section `.data.stm32_rtc_driver' of drivers/rtc/rtc-stm32.o: defined in discarded section `.exit.text' of drivers/rtc/rtc-stm32.o

This removes the extraneous annotation.

Fixes: 4e64350f42 ("rtc: add STM32 RTC driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-13 17:51:52 +01:00
Amelie Delaunay 4e64350f42 rtc: add STM32 RTC driver
This patch adds support for the STM32 RTC.

Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-13 01:40:31 +01:00
Russell King d748c9810b rtc: armada38x: make struct rtc_class_ops const
Armada38x wants to modify its rtc_class_ops to remove the interrupt
handling when there is no usable interrupt, but this means we leave
function pointers in writable memory.

Since rtc_class_ops is small, arrange to have two instances, one for
when we have interrupts, and one for when we have none, both marked
const.  This allows the compiler to place them in read-only memory,
which is better than placing them in __ro_after_init.

Thanks to Bhumika Goyal <bhumirks@gmail.com> for pointing out that
the structure was writable and submitting a patch to add
__ro_after_init.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-12 12:33:58 +01:00
Bhumika Goyal 8bc57e7f11 rtc: constify rtc_class_ops structures
Declare rtc_class_ops structures as const as they are only passed
as an argument to the function devm_rtc_device_register. This argument
is of type const struct rtc_class_ops *, so rtc_class_ops structures
having this property can be declared const.
Done using Coccinelle:

@r1 disable optional_qualifier @
identifier i;
position p;
@@
static struct rtc_class_ops i@p = {...};

@ok1@
identifier r1.i;
position p;
@@
devm_rtc_device_register(...,&i@p,...)

@bad@
position p!={r1.p,ok1.p};
identifier r1.i;
@@
i@p

@depends on !bad disable optional_qualifier@
identifier r1.i;
@@
+const
struct rtc_class_ops i;

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-11 17:23:06 +01:00
Martin Kaiser fef1eeb1a7 rtc: imxdi: use the security violation interrupt
The DryIce chipset has a dedicated security violation interrupt that is
triggered for security violations (if configured to do so).  According
to the publicly available imx258 reference manual, irq 56 is used for
this interrupt.

If an irq number is provided for the security violation interrupt,
install the same handler that we're already using for the "normal"
interrupt.

imxdi->irq is used only in the probe function, make it a local variable.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-11 17:23:05 +01:00
Emil Bartczak 644d4c366b rtc: mcp795: add alarm support.
This patch adds alarm support. This allows to configure the chip
to generate an interrupt when the alarm matches current time value.
Alarm can be programmed up to one year in the future
and is accurate to the second.

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-11 17:23:04 +01:00
Emil Bartczak 72877b51d0 rtc: mcp795: Add support for weekday.
This patch adds support for saving/loading weekday value from the chip.

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-11 17:23:04 +01:00
Gregory CLEMENT 844a3073c9 rtc: armada38x: Follow the new recommendation for errata implementation
According to RES-3124064:

The device supports CPU write and read access to the RTC time register.
However, due to this restriction, read and write from/to internal RTC
register may fail.

Workaround:
General setup:
1. Configure the RTC Mbus Bridge Timing Control register (offset 0x184A0)
   to value 0xFD4D4FFF
   Write RTC WRCLK Period to its maximum value (0x3FF)
   Write RTC WRCLK setup to 0x29
   Write RTC WRCLK High Time to 0x53 (default value)
   Write RTC Read Output Delay to its maximum value (0x1F)
   Mbus - Read All Byte Enable to 0x1 (default value)
2. Configure the RTC Test Configuration Register (offset 0xA381C) bit3
   to '1' (Reserved, Marvell internal)

For any RTC register read operation:
1. Read the requested register 100 times.
2. Find the result that appears most frequently and use this result
   as the correct value.

For any RTC register write operation:
1. Issue two dummy writes of 0x0 to the RTC Status register (offset
   0xA3800).
2. Write the time to the RTC Time register (offset 0xA380C).

This patch is based on the work of Shaker Daibes

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-11 17:23:03 +01:00
Vesa Jääskeläinen e3dcb74991 rtc: tps65910: use 'unsigned int' instead of 'unsigned' in arguments
Fixes checkpatch.pl warning:
WARNING: Prefer 'unsigned int' to bare use of 'unsigned'

Signed-off-by: Vesa Jääskeläinen <vesa.jaaskelainen@vaisala.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-10 01:32:51 +01:00
Vesa Jääskeläinen aecb57da7a rtc: tps65910: Add RTC calibration support
Texas Instrument's TPS65910 has support for compensating RTC crystal
inaccuracies. When enabled every hour RTC counter value will be compensated
with two's complement value.

Signed-off-by: Vesa Jääskeläinen <vesa.jaaskelainen@vaisala.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-10 01:32:33 +01:00
Fabien Lahoudere 666b5d1e9f rtc: rx8010: change lock mechanism
Remove spinlock and use the "rtc->ops_lock" from RTC subsystem instead.
spin_lock_irqsave() is not needed here because we do not have hard IRQs.

This patch fixes the following issue:

root@GE004097290448 b850v3:~# hwclock --systohc
root@GE004097290448 b850v3:~# hwclock --systohc
root@GE004097290448 b850v3:~# hwclock --systohc
root@GE004097290448 b850v3:~# hwclock --systohc
root@GE004097290448 b850v3:~# hwclock --systohc
[   82.108175] BUG: spinlock wrong CPU on CPU#0, hwclock/855
[   82.113660]  lock: 0xedb4899c, .magic: dead4ead, .owner: hwclock/855, .owner_cpu: 1
[   82.121329] CPU: 0 PID: 855 Comm: hwclock Not tainted 4.8.0-00042-g09d5410-dirty #20
[   82.129078] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
[   82.135609] Backtrace:
[   82.138090] [<8010d378>] (dump_backtrace) from [<8010d5c0>] (show_stack+0x20/0x24)
[   82.145664]  r7:ec936000 r6:600a0013 r5:00000000 r4:81031680
[   82.151402] [<8010d5a0>] (show_stack) from [<80401518>] (dump_stack+0xb4/0xe8)
[   82.158636] [<80401464>] (dump_stack) from [<8017b8b0>] (spin_dump+0x84/0xcc)
[   82.165775]  r10:00000000 r9:ec936000 r8:81056090 r7:600a0013 r6:edb4899c r5:edb4899c
[   82.173691]  r4:e5033e00 r3:00000000
[   82.177308] [<8017b82c>] (spin_dump) from [<8017bcb0>] (do_raw_spin_unlock+0x108/0x130)
[   82.185314]  r5:edb4899c r4:edb4899c
[   82.188938] [<8017bba8>] (do_raw_spin_unlock) from [<8094b93c>] (_raw_spin_unlock_irqrestore+0x34/0x54)
[   82.198333]  r5:edb4899c r4:600a0013
[   82.201953] [<8094b908>] (_raw_spin_unlock_irqrestore) from [<8065b090>] (rx8010_set_time+0x14c/0x188)
[   82.211261]  r5:00000020 r4:edb48990
[   82.214882] [<8065af44>] (rx8010_set_time) from [<80653fe4>] (rtc_set_time+0x70/0x104)
[   82.222801]  r7:00000051 r6:edb39da0 r5:edb39c00 r4:ec937e8c
[   82.228535] [<80653f74>] (rtc_set_time) from [<80655774>] (rtc_dev_ioctl+0x3c4/0x674)
[   82.236368]  r7:00000051 r6:7ecf1b74 r5:00000000 r4:edb39c00
[   82.242106] [<806553b0>] (rtc_dev_ioctl) from [<80284034>] (do_vfs_ioctl+0xa4/0xa6c)
[   82.249851]  r8:00000003 r7:80284a40 r6:ed1e9c80 r5:edb44e60 r4:7ecf1b74
[   82.256642] [<80283f90>] (do_vfs_ioctl) from [<80284a40>] (SyS_ioctl+0x44/0x6c)
[   82.263953]  r10:00000000 r9:ec936000 r8:7ecf1b74 r7:4024700a r6:ed1e9c80 r5:00000003
[   82.271869]  r4:ed1e9c80
[   82.274432] [<802849fc>] (SyS_ioctl) from [<80108520>] (ret_fast_syscall+0x0/0x1c)
[   82.282005]  r9:ec936000 r8:801086c4 r7:00000036 r6:00000000 r5:00000003 r4:0008e1bc
root@GE004097290448 b850v3:~#
Message from syslogd@GE004097290448 at Dec  3 11:17:08 ...
 kernel:[   82.108175] BUG: spinlock wrong CPU on CPU#0, hwclock/855

Message from syslogd@GE004097290448 at Dec  3 11:17:08 ...
 kernel:[   82.113660]  lock: 0xedb4899c, .magic: dead4ead, .owner: hwclock/855, .owner_cpu: 1
hwclock --systohc
root@GE004097290448 b850v3:~#

Signed-off-by: Fabien Lahoudere <fabien.lahoudere@collabora.co.uk>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-01-04 23:39:15 +01:00
Thomas Gleixner 8b0e195314 ktime: Cleanup ktime_set() usage
ktime_set(S,N) was required for the timespec storage type and is still
useful for situations where a Seconds and Nanoseconds part of a time value
needs to be converted. For anything where the Seconds argument is 0, this
is pointless and can be replaced with a simple assignment.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
2016-12-25 17:21:22 +01:00
Thomas Gleixner 2456e85535 ktime: Get rid of the union
ktime is a union because the initial implementation stored the time in
scalar nanoseconds on 64 bit machine and in a endianess optimized timespec
variant for 32bit machines. The Y2038 cleanup removed the timespec variant
and switched everything to scalar nanoseconds. The union remained, but
become completely pointless.

Get rid of the union and just keep ktime_t as simple typedef of type s64.

The conversion was done with coccinelle and some manual mopping up.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
2016-12-25 17:21:22 +01:00
Linus Torvalds b0b3a37b90 RTC for 4.10
Subsystem:
  - non-modular drivers are now explicitly non-modular
 
 New driver:
  - Epson Toyocom rtc-7301sf/dg
 
 Drivers:
  - cmos: reject unsupported alarm values wrt the RTC capabilities
  - ds1307: ACPI support
  - jz4740: DT support, jz4780 handling, can now be used as a system power
  controller
  - mcp795: many fixes, in particular proper month handling
  - twl: driver is now DT only
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Merge tag 'rtc-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
  "Subsystem:
   - non-modular drivers are now explicitly non-modular

  New driver:
    - Epson Toyocom rtc-7301sf/dg

  Drivers:
   - cmos: reject unsupported alarm values wrt the RTC capabilities
   - ds1307: ACPI support
   - jz4740: DT support, jz4780 handling, can now be used as a system
     power controller
   - mcp795: many fixes, in particular proper month handling
   - twl: driver is now DT only"

* tag 'rtc-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (31 commits)
  rtc: mcp795: Fix whitespace and indentation.
  rtc: mcp795: Prefer using the BIT() macro.
  rtc: mcp795: fix month write resetting date to 1.
  rtc: mcp795: fix time range difference between linux and RTC chip.
  rtc: mcp795: fix bitmask value for leap year (LP).
  rtc: mcp795: use bcd2bin/bin2bcd.
  rtc: add support for EPSON TOYOCOM RTC-7301SF/DG
  rtc: ds1307: Add ACPI support
  rtc: imxdi: (trivial) fix a typo
  rtc: ds1374: Merge conditional + WARN_ON()
  rtc: twl: make driver DT only
  rtc: twl: kill static variables
  rtc: fix typos in Kconfig
  rtc: jz4740: make the driver builtin only
  rtc: jz4740: remove unused EXPORT_SYMBOL
  Documentation: bindings: fix twl-rtc documentation
  rtc: Enable compile testing for Maxim and Samsung drivers
  MIPS: jz4740: Remove obsolete code
  MIPS: qi_lb60: Probe RTC driver from DT and use it as power controller
  MIPS: jz4740: DTS: Probe the jz4740-rtc driver from devicetree
  ...
2016-12-18 18:18:03 -08:00
Emil Bartczak d3e5925902 rtc: mcp795: Fix whitespace and indentation.
Fix whitespace and indentation errors and the following
checkpatch warnings:
- line 15: Block comments use a trailing */ on a separate line
- line 256: Line over 80 characters
No code change.

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-12-19 00:59:25 +01:00
Emil Bartczak a2b4299751 rtc: mcp795: Prefer using the BIT() macro.
This patch doesn't change the code but replaces all bitmask values
with the BIT(x) macro.

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-12-19 00:59:24 +01:00
Emil Bartczak 43d0b10f60 rtc: mcp795: fix month write resetting date to 1.
According to Microchip errata some combinations of date and month
values may result in the date being reset to 1, even if the date
is also written with the month (for example 31-07 or 31-08).
As a workaround avoid writing date and month values within the same
Write command. Instead, terminate the Write command after loading
the date and begin a new command to write the month. In addition,
disable the oscillator before loading the new values. This is done
by ensuring both the ST and EXTOSC bits are cleared and waiting for
the OSCON bit to clear.

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-12-19 00:59:23 +01:00
Emil Bartczak 26eeefd595 rtc: mcp795: fix time range difference between linux and RTC chip.
In linux rtc_time struct, tm_mon range is 0~11, while in RTC HW REG,
month range is 1~12. This patch adjusts difference of them.

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-12-19 00:59:23 +01:00
Emil Bartczak e72765c648 rtc: mcp795: fix bitmask value for leap year (LP).
According the datasheet the leap year is a fifth bit in month register.

Signed-off-by: Emil Bartczak <emilbart@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-12-19 00:59:22 +01:00