linux-toradex.git/drivers/rtc, branch v4.4-rc6

rtc: da9063: fix access ordering error during RTC interrupt at system power on

2015-12-20T12:39:29+00:00

This fix alters the ordering of the IRQ and device registrations in the RTC
driver probe function. This change will apply to the RTC driver that supports
both DA9063 and DA9062 PMICs.

A problem could occur with the existing RTC driver if:

A system is started from a cold boot using the PMIC RTC IRQ to initiate a
power on operation. For instance, if an RTC alarm is used to start a
platform from power off.
The existing driver IRQ is requested before the device has been properly
registered.
i.e.
    ret = devm_request_threaded_irq()
comes before
    rtc->rtc_dev = devm_rtc_device_register();

In this case, the interrupt can be called before the device has been
registered and the handler can be called immediately. The IRQ handler
da9063_alarm_event() contains the function call

    rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF | RTC_AF);

which in turn tries to access the unavailable rtc->rtc_dev.

The fix is to reorder the functions inside the RTC probe. The IRQ is
requested after the RTC device resource has been registered so that
get_irq_byname is the last thing to happen.

Signed-off-by: Steve Twiss 
Signed-off-by: Alexandre Belloni

rtc: rk808: Compensate for Rockchip calendar deviation on November 31st

2015-12-20T12:39:00+00:00

In A.D. 1582 Pope Gregory XIII found that the existing Julian calendar
insufficiently represented reality, and changed the rules about
calculating leap years to account for this. Similarly, in A.D. 2013
Rockchip hardware engineers found that the new Gregorian calendar still
contained flaws, and that the month of November should be counted up to
31 days instead. Unfortunately it takes a long time for calendar changes
to gain widespread adoption, and just like more than 300 years went by
before the last Protestant nation implemented Greg's proposal, we will
have to wait a while until all religions and operating system kernels
acknowledge the inherent advantages of the Rockchip system. Until then
we need to translate dates read from (and written to) Rockchip hardware
back to the Gregorian format.

This patch works by defining Jan 1st, 2016 as the arbitrary anchor date
on which Rockchip and Gregorian calendars are in sync. From that we can
translate arbitrary later dates back and forth by counting the number
of November/December transitons since the anchor date to determine the
offset between the calendars. We choose this method (rather than trying
to regularly "correct" the date stored in hardware) since it's the only
way to ensure perfect time-keeping even if the system may be shut down
for an unknown number of years. The drawback is that other software
reading the same hardware (e.g. mainboard firmware) must use the same
translation convention (including the same anchor date) to be able to
read and write correct timestamps from/to the RTC.

Signed-off-by: Julius Werner 
Reviewed-by: Douglas Anderson 
Signed-off-by: Alexandre Belloni

rtc: ds1307: fix alarm reading at probe time

2015-11-26T17:11:26+00:00

With the actual code, read_alarm() always returns -EINVAL when called
during the RTC device registration. This prevents from retrieving an
already configured alarm in hardware.

This patch fixes the issue by moving the HAS_ALARM bit configuration
(if supported by the hardware) above the rtc_device_register() call.

Signed-off-by: Simon Guinot 
Signed-off-by: Alexandre Belloni

rtc: ds1307: fix kernel splat due to wakeup irq handling

2015-11-25T11:15:44+00:00

Since commit 3fffd1283927 ("i2c: allow specifying
separate wakeup interrupt in device tree") we have
automatic wakeup irq support for i2c devices. That
commit missed the fact that rtc-1307 had its own
wakeup irq handling and ended up introducing a
kernel splat for at least Beagle x15 boards.

Fix that by reverting original commit _and_ passing
correct interrupt names on DTS so i2c-core can
choose correct IRQ as wakeup.

Now that we have automatic wakeirq support, we can
revert the original commit which did it manually.

Fixes the following warning:

[   10.346582] WARNING: CPU: 1 PID: 263 at linux/drivers/base/power/wakeirq.c:43 dev_pm_attach_wake_irq+0xbc/0xd4()
[   10.359244] rtc-ds1307 2-006f: wake irq already initialized

Cc: Tony Lindgren 
Cc: Nishanth Menon 
Signed-off-by: Felipe Balbi 
Acked-by: Tony Lindgren 
Acked-by: Arnd Bergmann 
Signed-off-by: Alexandre Belloni

Merge tag 'rtc-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

2015-11-10T18:01:21+00:00

Pull RTC updates from Alexandre Belloni:
 "Core:
   - Fix rtctest error path

  New drivers:
   - Microcrystal RV8803

  Subsystem wide cleanups:
   - remove misuse of IRQF_NO_SUSPEND flag

  Drivers:
   - at91rm9200: clear RTC alarm status flag prior to suspending
   - davinci: remove incorrect reference to probe function
   - ds1307: Fix alarm programming for mcp794xx
   - ds1390: trickle charger support, fix ds1390_get_reg
   - isl1208: Pass the IRQF_ONESHOT flag
   - opal: fix type of token
   - pcf2127: fix RTC_READ_VL, remove useless driver version
   - pcf85063: return an error when date is invalid
   - pcf8563: add CLKOUT to common clock framework
   - rx8025: remove unnecessary braces
   - s3c: Set year, month, day value for setting alarm
   - stmp3xxx: unify register access macros
   - License fixes: pcf2127, da9063
   - wakeup-source support for isl12057 and opal"

* tag 'rtc-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (23 commits)
  rtc: Add a driver for Micro Crystal RV8803
  rtc: s3c: Set year, month, day value for setting alarm
  rtc: ds1307: Fix alarm programming for mcp794xx
  rtc: isl12057: enable support for the standard "wakeup-source" property
  rtc: opal: enable support for the stardard "wakeup-source" property
  rtc: isl1208: Pass the IRQF_ONESHOT flag
  rtc: pcf8563: add CLKOUT to common clock framework
  rtc: davinci: remove incorrect reference to probe function
  rtc: at91rm9200: clear RTC alarm status flag prior to suspending
  rtc: pcf2127: remove useless driver version
  rtc: pcf2127: fix reading uninitialized value on RTC_READ_VL ioctl
  rtc: stmp3xxx: unify register access macros
  rtc: da9063: GPL copyright inconsistency fix
  rtc: pcf85063: return an error when date is invalid
  rtc: rx8025: remove unnecessary braces
  rtc: ds1343: remove misuse of IRQF_NO_SUSPEND flag
  rtc: ab8500: remove misuse of IRQF_NO_SUSPEND flag
  rtc: pl031: remove misuse of IRQF_NO_SUSPEND flag
  rtc: opal: fix type of token
  rtc: ds1390: Add trickle charger device tree binding
  ...

rtc: Add a driver for Micro Crystal RV8803

2015-11-08T13:12:32+00:00

This driver supports the following functions:
 - reading and settings time
 - alarms when connected to an IRQ
 - reading and clearing the voltage low flags
 - nvram

Signed-off-by: Alexandre Belloni

rtc: s3c: Set year, month, day value for setting alarm

2015-11-08T13:12:31+00:00

This patch sets year, month, day value for set_alarm function.
The current driver omits to set the values.

This fixes setting wake alarm for dates different than current day.
Without the patch the alarm scheduled for tomorrow would fire today on
chosen time.

Signed-off-by: Donggeun Kim 
Signed-off-by: MyungJoo Ham 
Signed-off-by: KyungMin Park 
[k.kozlowski: Rebase and test the patch, update commit message]
Signed-off-by: Krzysztof Kozlowski 
Signed-off-by: Alexandre Belloni

rtc: ds1307: Fix alarm programming for mcp794xx

2015-11-08T13:12:31+00:00

mcp794xx alarm registers must be written in BCD format. However, the
alarm programming logic neglected this by adding one to the value
after bin2bcd conversion has been already done, writing bad values
to month register in case the alarm being set is in October. In this
case, the alarm month value becomes 0x0a instead of the expected 0x10.

Fix by moving the +1 addition within the bin2bcd call also.

Fixes: 1d1945d261a2 ("drivers/rtc/rtc-ds1307.c: add alarm support for mcp7941x chips")

Signed-off-by: Tero Kristo 
Acked-by: Nishanth Menon 
Signed-off-by: Alexandre Belloni

rtc: isl12057: enable support for the standard "wakeup-source" property

2015-11-08T13:12:30+00:00

Though the isl12057 rtc driver should and will continue to support the
legacy "isil,irq2-can-wakeup-machine" property to enable RTC as the
wakeup source, we need to add support for the new standard property
"wakeup-source".

This patch adds support for "wakeup-source" property in addition to the
existing "isil,irq2-can-wakeup-machine" property.

Cc: Alessandro Zummo 
Cc: Alexandre Belloni 
Cc: rtc-linux@googlegroups.com
Signed-off-by: Sudeep Holla 
Signed-off-by: Alexandre Belloni

rtc: opal: enable support for the stardard "wakeup-source" property

2015-11-08T13:12:30+00:00

Though the opal rtc driver should and will continue to support the legacy
"has-tpo" property to enable RTC as the wakeup source, we need to add
support for the new standard property "wakeup-source"

This patch adds support for "wakeup-source" property in addition to the
existing "has-tpo" property.

Cc: Alessandro Zummo 
Cc: Alexandre Belloni 
Cc: rtc-linux@googlegroups.com
Signed-off-by: Sudeep Holla 
Signed-off-by: Alexandre Belloni