Commit Graph

98 Commits

Author SHA1 Message Date
Heiner Kallweit
e553170a59 rtc: ds1307: factor out offset to struct chip_desc
Factor out offset to struct chip_desc and remove it from struct ds1307.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-09-01 01:10:17 +02:00
Heiner Kallweit
1efb98ba5e rtc: ds1307: factor out rtc_ops to struct chip_desc
Factor out rtc_ops to struct chip_desc and use ds13xx_rtc_ops as default.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-09-01 01:10:16 +02:00
Heiner Kallweit
4594712705 rtc: ds1307: factor out irq_handler to struct chip_desc
Factor out irq_handler to struct chip_desc and use ds1307_irq as default.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-09-01 01:10:16 +02:00
Heiner Kallweit
82e2d43f63 rtc: ds1307: improve irq setup
Change the usage of variable want_irq to reflect its name. Don't set
it to true in case wakeup is enabled but no interrupt number is given.
In addition set variable ds1307_can_wakeup_device if chip->alarm
is set only.
This allows to simplify the code and make it better understandable.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-09-01 01:10:15 +02:00
Heiner Kallweit
7624df482d rtc: ds1307: constify struct chip_desc variables
Constify struct chip_desc variables.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-09-01 01:10:14 +02:00
Heiner Kallweit
d8490fd55a rtc: ds1307: improve trickle charger initialization
Instead of storing the trickle_charger_setup value in struct chip_desc
we can let function ds1307_trickle_init return it because it's used
in the probe function only.
This allows us to constify struct chip_desc variables in a next step.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-09-01 01:10:13 +02:00
Heiner Kallweit
0b6ee80594 rtc: ds1307: factor out bbsqi bit to struct chip_desc
Factor out the bbsqi bit to struct chip_desc.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-09-01 01:10:13 +02:00
Heiner Kallweit
340fd7bce0 rtc: ds1307: remove member irq from struct ds1307
The irq number is used in the probe function only, so we don't have
to store it in struct ds1307.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-09-01 01:10:12 +02:00
Heiner Kallweit
11909f0be7 rtc: ds1307: remove legacy check for "isil, irq2-can-wakeup-machine" property
Commit 8b44f5be20 ("ARM: dts: armada: replace isil,irq2-can-wakeup-machine with wakeup-source property")
removed the last usage of "isil,irq2-can-wakeup-machine" almost
two years ago. So I think we can get rid of supporting this
legacy binding.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-07-31 00:17:45 +02:00
Alexandre Belloni
bed8e28047 rtc: ds1307: remove ds1307_remove
ds1307_remove() is now empty, remove it

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-07-07 13:14:25 +02:00
Alexandre Belloni
abc925f72c rtc: ds1307: use generic nvmem
Instead of adding a binary sysfs attribute from the driver (which suffers
from a race condition as the attribute appears after the device), use the
core to register an nvmem device.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-07-07 13:14:23 +02:00
Alexandre Belloni
69b119a642 rtc: ds1307: switch to rtc_register_device
This removes a possible race condition and crash and allows for further
improvement of the driver.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-07-07 13:14:21 +02:00
Sean Nyekjaer
300a7735be rtc: ds1307: add ds1308 variant
The ds1308 variant is very similar to the already supported ds1338
variant, it have more debug registers and a square wave clock output.

Signed-off-by: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-07-06 22:37:17 +02:00
Heiner Kallweit
e48585dec2 rtc: ds1307: factor out century bit handling
The driver has lots of places with chip-specific code what doesn't
necessarily facilitate maintenance.

Let's describe chip-specific differences in century bit handling
in struct chip_desc to improve this.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-07-06 22:37:08 +02:00
Heiner Kallweit
078f3f6452 rtc: ds1307: use regmap_update_bits where applicable
After the switch to regmap we can now make use of regmap_update_bits
to simplify read/modify/write ops.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-07-05 23:12:34 +02:00
Marek Vasut
ee0981be77 rtc: ds1307: Add support for Epson RX8130CE
Add support for yet another RTC chip, Epson RX8130CE. This time around,
the chip has slightly permutated registers and also the register starts
at 0x10 instead of 0x0 .

So far, we only support the RTC and NVRAM parts of the chip, Alarm and
Timer is not supported.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Nishanth Menon <nm@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-06-24 22:59:38 +02:00
Alexandre Belloni
4b9e2a0c05 rtc: ds1307: avoid using rtc-name
ds1307->rtc->name is a copy of ds1307->name, use it instead.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-06-03 10:55:26 +02:00
David Lowe
8066360744 rtc: rtc-ds1307: enable support for mcp794xx as a wakeup source without IRQ
This patch extends the fixes for ds1337, ds1339, ds3231 in commit
8bc2a40730 ("rtc: ds1307: add support for the DT property
'wakeup-source'") to mcp794xx devices, so that those parts can similarly be
used as a wakeup source without an IRQ to the processor.

Tested on Raspberry Pi ZeroW with MCP79400.

Signed-off-by: David Lowe <dave-lowe@ntlworld.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-05-31 09:17:00 +02:00
Heiner Kallweit
11e5890b53 rtc: ds1307: convert driver to regmap
This patch converts the ds1307 driver to using regmap. It's a rather
big patch and I can test with DS3231 only. With this chip it's
working fine.

I'd appreciate if people with other supported hardware could test as
well.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-05-26 03:03:35 +02:00
Alexandre Belloni
db2f814194 rtc: ds1307: Add m41t0 to OF device ID table
m41t0 was added to the I2C device ID table but not the OF table. Fix that.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-04-14 12:08:53 +02:00
Stefan Agner
8566f70c8a rtc: ds1307: support m41t0 variant
The m41t0 variant is very similar to the already supported m41t00
variant, with the notable exception of the oscillator fail bit.
The data sheet notes:

  If the oscillator fail (OF) bit is internally set to a '1,' this
  indicates that the oscillator has either stopped, or was stopped
  for some period of time and can be used to judge the validity of
  the clock and date data.

The bit will get cleared with a regular write of the system time,
so no changes are needed to clear it.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-04-14 12:08:53 +02:00
Javier Martinez Canillas
7ef6d2c266 rtc: ds1307: Add OF device ID table
The driver doesn't have a struct of_device_id table but supported devices
are registered via Device Trees. This is working on the assumption that a
I2C device registered via OF will always match a legacy I2C device ID and
that the MODALIAS reported will always be of the form i2c:<device>.

But this could change in the future so the correct approach is to have an
OF device ID table if the devices are registered via OF.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-03-09 01:29:20 +01:00
Tin Huynh
9c19b8930d rtc: ds1307: Add ACPI support
This patch enables ACPI support for rtc-ds1307 driver.

Signed-off-by: Tin Huynh <tnhuynh@apm.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-12-19 00:59:07 +01:00
Alexandre Belloni
78aaa06d79 rtc: ds1307: add Intersil ISL12057 support
Intersil ISL12057 is a drop-in replacement for DS1337. It can be supported
by the ds1307 driver.

Acked-by: Arnaud Ebalard <arno@natisbad.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-08-31 18:21:34 +02:00
Alexandre Belloni
50d6c0ea81 rtc: ds1307: fix century bit support
Add an option to properly support the century bit of ds1337 and compatibles
and ds1340.
Because the driver had a bug until now, it is not possible to switch users
to the fixed code directly as RTCs in the field will wrongly have the
century bit set.

Acked-by: Arnaud Ebalard <arno@natisbad.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-08-31 18:21:34 +02:00
Uwe Kleine-König
56d86a7e79 rtc: simplify implementations of read_alarm
Since commit d68778b80d ("rtc: initialize output parameter for read
alarm to "uninitialized"") there is no need to explicitly set
unsupported members to -1. So drop the respective assignments from
drivers.

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-07-09 10:24:45 +02:00
Keerthy
e29385fab0 rtc: ds1307: Fix relying on reset value for weekday
The reset value of weekday is 0x1. This is wrong since
the reset values of the day/month/year make up to Jan 1 2001.
When computed weekday comes out to be Monday. On a scale
of 1-7(Sunday - Saturday) it should be 0x2. So we should not
be relying on the reset value.

Hence compute the wday using the current date/month/year values.
Check if reset wday is any different from the computed wday,
If different then set the wday which we computed using
date/month/year values.

Document Referred:
http://ww1.microchip.com/downloads/en/DeviceDoc/20002266F.pdf

Fixes: 1d1945d261 "drivers/rtc/rtc-ds1307.c: add alarm support for mcp7941x chips"
Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-07-09 10:24:44 +02:00
Stephen Boyd
7457d5f588 rtc: ds1307: Remove CLK_IS_ROOT
This flag is a no-op now (see commit 47b0eeb3dc "clk: Deprecate
CLK_IS_ROOT", 2016-02-02) so remove it.

Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Michael Tatarinov <kukabu@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-05-20 12:33:51 +02:00
Nicolas Boullis
5919fb97dd rtc: ds1307: ensure that any pending alarm is cleared before a new alarm is enabled
If a previously-set alarm was disabled and then triggered, it may still
be pending when a new alarm is configured.

Then, if the alarm is enabled before the pending alarm is cleared, then
an interrupt is immediately raised.

Unfortunately, when the alarm is cleared and enabled during the same I²C
block write, the chip (at least the DS1339 I have) considers that the
alarm is enabled before it is cleared, and raises an interrupt.

This patch ensures that the pending alarm is cleared before the alarm is
enabled.

Signed-off-by: Nicolas Boullis <nboullis@debian.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-05-20 12:33:51 +02:00
Nicolas Boullis
1d87951c39 rtc: ds1307: fix ds1307_native_smbus_read_block_data function
The i2c_smbus_read_i2c_block_data function returns 0 on success, not the
number of bytes written.

Hence, when there are 32 bytes or less to send, the
ds1307_native_smbus_write_block_data function returns 0 on success,
while it returns the number of bytes when there are more than 32.

The ds1307_write_block_data always returns the number of bytes on
success.

Signed-off-by: Nicolas Boullis <nboullis@debian.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-05-20 12:33:51 +02:00
Nishanth Menon
38a7a73e8e rtc: ds1307: Use irq when available for wakeup-source device
With commit 8bc2a40730 ("rtc: ds1307: add support for the
DT property 'wakeup-source'") we lost the ability for rtc irq
functionality for devices that are actually hooked on a real IRQ
line and have capability to wakeup as well. This is not an expected
behavior. So, instead of just not requesting IRQ, skip the IRQ
requirement only if interrupts are not defined for the device.

Fixes: 8bc2a40730 ("rtc: ds1307: add support for the DT property 'wakeup-source'")
Reported-by: Tony Lindgren <tony@atomide.com>
Cc: Michael Lange <linuxstuff@milaw.biz>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-04-21 23:21:00 +02:00
Zhuang Yuyao
9a3dce62cc rtc: ds1307: ds3231 temperature s16 overflow
while retrieving temperature from ds3231, the result may be overflow
since s16 is too small for a multiplication with 250.

ie. if temp_buf[0] == 0x2d, the result (s16 temp) will be negative.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Tested-by: Michael Tatarinov <kukabu@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-04-21 23:20:59 +02:00
Akinobu Mita
6c6ff145b3 rtc: ds1307: add clock provider support for DS3231
DS3231 has programmable square-wave output signal.
This enables to use this feature as a clock provider of
common clock framework.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Reviewed-by: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-03-14 17:08:13 +01:00
Akinobu Mita
445c02076f rtc: ds1307: add temperature sensor support for ds3231
DS3231 has the temperature registers with a resolution of 0.25
degree celsius.  This enables to get the value through hwmon.

	# cat /sys/class/i2c-adapter/i2c-2/2-0068/hwmon/hwmon0/temp1_input
	21000

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-02-04 23:44:17 +01:00
Michael Lange
8bc2a40730 rtc: ds1307: add support for the DT property 'wakeup-source'
For RTC chips with no IRQ directly connected to the SoC, the RTC chip
can be forced as a wakeup source by stating that explicitly in
the device's .dts file using the "wakeup-source" boolean property.
This will guarantee the 'wakealarm' sysfs entry is available on the
device, if supported by the RTC.

With these changes to the driver rtc-ds1307 and the necessary entries
in the .dts file, I get an working ds1337 RTC on the Witty Pi extension
board by UUGear for the Raspberry Pi.

An example for the entry in the .dts file:

	rtc: ds1337@68 {
		compatible = "dallas,ds1337";
		reg = <0x68>;
		wakeup-source;

If the "wakeup-source" property is set, do not request an IRQ.
Set also UIE mode to unsupported, to get a working 'hwclock' binary.

Signed-off-by: Michael Lange <linuxstuff@milaw.biz>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-02-04 23:44:17 +01:00
Rasmus Villemoes
ff67abd236 rtc: use %ph for short hex dumps
This makes the generated code slightly smaller.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-01-11 20:19:58 +01:00
Simon Guinot
3abb1ada21 rtc: ds1307: fix alarm reading at probe time
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 <simon.guinot@sequanux.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-11-26 18:11:26 +01:00
Felipe Balbi
51c4cfef56 rtc: ds1307: fix kernel splat due to wakeup irq handling
Since commit 3fffd12839 ("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 <tony@atomide.com>
Cc: Nishanth Menon <nm@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-11-25 12:15:44 +01:00
Tero Kristo
62c8c20af9 rtc: ds1307: Fix alarm programming for mcp794xx
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: 1d1945d261 ("drivers/rtc/rtc-ds1307.c: add alarm support for mcp7941x chips")

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-11-08 14:12:31 +01:00
Vladimir Zapolskiy
ca7c14d3a1 rtc: ds1307: clean up ds1307_nvram_read()/ds1307_nvram_write()
The change removes redundant sysfs binary file boundary checks, since
this task is already done on caller side in fs/sysfs/file.c

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05 13:19:10 +02:00
Krzysztof Kozlowski
b28845433e rtc: Drop owner assignment from i2c_driver
i2c_driver does not need to set an owner because i2c_register_driver()
will set it.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05 13:19:06 +02:00
Nishanth Menon
7abea617a4 rtc: ds1307: Support optional wakeup interrupt source
With the recent pinctrl-single changes, SoCs such as Texas
Instrument's OMAP processors can treat wake-up events from deeper idle
states as interrupts.

Let's add support for the optional second interrupt for wake-up using
the generic wakeirq support added in commit 4990d4fe32 ("PM /
Wakeirq: Add automated device wake IRQ handling")

Finally, to pass the wake-up interrupt in the dts file,
interrupts-extended property needs to be passed.

This is similar in approach to commit 2a0b965cfb ("serial: omap: Add
support for optional wake-up") + ee83bd3b64 ("serial: omap: Switch
wake-up interrupt to generic wakeirq")

Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05 13:19:05 +02:00
Nishanth Menon
eac7237fd8 rtc: ds1307: Sort the headers
It is always a good practice to keep the #includes sorted

Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05 13:19:05 +02:00
Nishanth Menon
c598319136 rtc: ds1307: Switch to managed irq allocation
Since we are not doing anything fancy in remove function that requires
us to sequence IRQ free operation, we might as well switch over to devm_
equivalent of managed IRQ allocation and remove the explicit free_irq
since it'd be done automatically at remove.

Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05 13:19:05 +02:00
Felipe Balbi
2fb07a10e0 rtc: ds1307: Convert to threaded IRQ
The driver currently emulates the concept of threaded IRQ using a
workqueue, which it really does not need to. Instead, switch over to
threaded_irq handlers which is meant precisely for the same purpose.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05 13:19:05 +02:00
Nishanth Menon
e3edd67141 rtc: ds1307: Enable the mcp794xx alarm after programming time
Alarm interrupt enable register is at offset 0x7, while the time
registers for the alarm follow that. When we program Alarm interrupt
enable prior to programming the time, it is possible that previous
time value could be close or match at the time of alarm enable
resulting in interrupt trigger which is unexpected (and does not match
the time we expect it to trigger).

To prevent this scenario from occuring, program the ALM0_EN bit only
after the alarm time is appropriately programmed.

Ofcourse, I2C programming is non-atomic, so there are loopholes where
the interrupt wont trigger if the time requested is in the past at
the time of programming the ALM0_EN bit. However, we will not have
unexpected interrupts while the time is programmed after the interrupt
are enabled.

Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@linaro.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-06-25 01:13:46 +02:00
Tomas Novotny
f4199f8557 rtc: ds1307: add support for mcp7940x chips
MCP7940x is same RTC as MCP7941x.  The difference is that MCP7941x chips
contain additional EEPROM on a different i2c address.

DS1307 driver already supports MCP7941x, so just add a new i2c device id
and rename functions and defines accordingly.

Signed-off-by: Tomas Novotny <tomas@novotny.cz>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-10 17:41:15 -08:00
Matti Vaittinen
33b04b7b7c rtc: ds1307: add trickle charger device tree binding
Some DS13XX devices have "trickle chargers".  Introduce a device tree
binding for specifying the trickle charger configuration for ds1339.

Only ds1339 dt binding is supported because this is the only chip I have.
I _assume_ the code would have worked on other allready supported chips.
However I cannot check the resistor values for the other chips or test
them.  For other chips the driver code works as earlier Eg.  it does not
check the dt bindings at all

Signed-off-by: Matti Vaittinen <matti.vaittinen@nsn.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Pavel Machek <pavel@denx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-14 02:18:18 +02:00
Simon Guinot
1d1945d261 drivers/rtc/rtc-ds1307.c: add alarm support for mcp7941x chips
Add alarm support for the Microchip RTC devices MCP794xx.  Note that two
programmable alarms are provided by the chip but only one is used by the
driver.

Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:21:20 -07:00
Simon Guinot
5ea735144d drivers/rtc/rtc-ds1307.c: fix sysfs wakealarm attribute creation
In order to allow the creation of the sysfs attribute wakealarm, this
patch moves the device_set_wakeup_capable() call above the RTC device
registration.

Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:21:20 -07:00