Commit Graph

27 Commits

Author SHA1 Message Date
Linus Torvalds 9dbd83f665 RTC for 5.4
Subsystem:
  - add debug message when registration fails
 
 New drivers:
  - Amlogic Virtual Wake
  - Freescale FlexTimer Module alarm
 
 Drivers:
  - remove superfluous error messages
  - convert to i2c_new_dummy_device and devm_i2c_new_dummy_device
  - Remove dev_err() usage after platform_get_irq()
  - Set RTC range for: pcf2123, pcf8563, snvs.
  - pcf2127: tamper detection and watchdog support
  - pcf85363: fix regmap issue
  - sun6i: H6 support
  - remove w90x900/nuc900 driver
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Merge tag 'rtc-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "Two new drivers and the new pcf2127 feature make the bulk of the
  additions. The rest are the usual fixes and new features.

  Subsystem:
   - add debug message when registration fails

  New drivers:
   - Amlogic Virtual Wake
   - Freescale FlexTimer Module alarm

  Drivers:
   - remove superfluous error messages
   - convert to i2c_new_dummy_device and devm_i2c_new_dummy_device
   - Remove dev_err() usage after platform_get_irq()
   - Set RTC range for: pcf2123, pcf8563, snvs.
   - pcf2127: tamper detection and watchdog support
   - pcf85363: fix regmap issue
   - sun6i: H6 support
   - remove w90x900/nuc900 driver"

* tag 'rtc-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (51 commits)
  rtc: meson: mark PM functions as __maybe_unused
  rtc: sc27xx: Remove clearing SPRD_RTC_POWEROFF_ALM_FLAG flag
  dt-bindings: rtc: ds1307: add rx8130 compatible
  rtc: sun6i: Allow using as wakeup source from suspend
  rtc: pcf8563: let the core handle range offsetting
  rtc: pcf8563: remove useless indirection
  rtc: pcf8563: convert to devm_rtc_allocate_device
  rtc: pcf8563: add Microcrystal RV8564 compatible
  rtc: pcf8563: add Epson RTC8564 compatible
  rtc: s35390a: convert to devm_i2c_new_dummy_device()
  rtc: max77686: convert to devm_i2c_new_dummy_device()
  rtc: pcf85363/pcf85263: fix regmap error in set_time
  rtc: snvs: switch to rtc_time64_to_tm/rtc_tm_to_time64
  rtc: snvs: set range
  rtc: snvs: fix possible race condition
  rtc: pcf2127: bugfix: watchdog build dependency
  rtc: pcf2127: add tamper detection support
  rtc: pcf2127: add watchdog feature support
  rtc: pcf2127: bugfix: read rtc disables watchdog
  rtc: pcf2127: cleanup register and bit defines
  ...
2019-09-22 11:05:43 -07:00
Alejandro González d76a81d0c2 rtc: sun6i: Allow using as wakeup source from suspend
This patch allows userspace to set up wakeup alarms on any RTC handled by the
sun6i driver, and adds the necessary PM operations to allow resuming from
suspend when the configured wakeup alarm fires a IRQ. Of course, that the
device actually resumes depends on the suspend state and how a particular
hardware reacts to it, but that is out of scope for this patch.

I've tested these changes on a Pine H64 model B, which contains a
Allwinner H6 SoC, with the help of CONFIG_PM_TEST_SUSPEND kernel option.
These are the interesting outputs from the kernel and commands which
show that it works. As every RTC handled by this driver is largely the
same, I think that it shouldn't introduce any regression on other SoCs,
but I may be wrong.

[    1.092705] PM: test RTC wakeup from 'freeze' suspend
[    1.098230] PM: suspend entry (s2idle)
[    1.212907] PM: suspend devices took 0.080 seconds
(The SoC freezes for some seconds)
[    3.197604] PM: resume devices took 0.104 seconds
[    3.215937] PM: suspend exit

[    1.092812] PM: test RTC wakeup from 'mem' suspend
[    1.098089] PM: suspend entry (deep)
[    1.102033] PM: suspend exit
[    1.105205] PM: suspend test failed, error -22

In any case, the RTC alarm interrupt gets fired as exptected:

$ echo +5 > /sys/class/rtc/rtc0/wakealarm && sleep 5 && grep rtc /proc/interrupts
 29:          1          0          0          0     GICv2 133 Level     7000000.rtc

Signed-off-by: Alejandro González <alejandro.gonzalez.correo@gmail.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Link: https://lore.kernel.org/r/20190821210056.11995-1-alejandro.gonzalez.correo@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-09-01 11:01:02 +02:00
Ondrej Jirman b60ff2cfb5 rtc: sun6i: Add support for H6 RTC
RTC on H6 is mostly the same as on H5 and H3. It has slight differences
mostly in features that are not yet supported by this driver.

Some differences are already stated in the comments in existing code.
One other difference is that H6 has extra bit in LOSC_CTRL_REG, called
EXT_LOSC_EN to enable/disable external low speed crystal oscillator.

It also has bit EXT_LOSC_STA in LOSC_AUTO_SWT_STA_REG, to check whether
external low speed oscillator is working correctly.

This patch adds support for enabling LOSC when necessary:

- during reparenting
- when probing the clock

H6 also has capacbility to automatically reparent RTC clock from
external crystal oscillator, to internal RC oscillator, if external
oscillator fails. This is enabled by default. Disable it during
probe.

Signed-off-by: Ondrej Jirman <megous@megous.com>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Link: https://lore.kernel.org/r/20190820151934.3860-3-megous@megous.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-08-23 16:20:50 +02:00
Stephen Boyd 21ef77de22 rtc: sun6i: Don't reference clk_init_data after registration
A future patch is going to change semantics of clk_register() so that
clk_hw::init is guaranteed to be NULL after a clk is registered. Avoid
referencing this member here so that we don't run into NULL pointer
exceptions.

Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Reported-by: "kernelci.org bot" <bot@kernelci.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lkml.kernel.org/r/20190815160020.183334-4-sboyd@kernel.org
Acked-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-08-16 10:21:07 -07:00
Stephen Boyd faac910201 rtc: Remove dev_err() usage after platform_get_irq()
We don't need dev_err() messages when platform_get_irq() fails now that
platform_get_irq() prints an error message itself when something goes
wrong. Let's remove these prints with a simple semantic patch.

// <smpl>
@@
expression ret;
struct platform_device *E;
@@

ret =
(
platform_get_irq(E, ...)
|
platform_get_irq_byname(E, ...)
);

if ( \( ret < 0 \| ret <= 0 \) )
{
(
-if (ret != -EPROBE_DEFER)
-{ ...
-dev_err(...);
-... }
|
...
-dev_err(...);
)
...
}
// </smpl>

While we're here, remove braces on if statements that only have one
statement (manually).

Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: linux-rtc@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20190730181557.90391-40-swboyd@chromium.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-08-13 10:53:10 +02:00
Linus Torvalds edafb6fe42 RTC for 5.3
Drivers:
  - ds1307: properly handle oscillator failure flags
  - imx-sc: alarm support
  - pcf2123: alarm support, correct offset handling
  - sun6i: add R40 support
  - simplify getting the adapter of an i2c client
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Merge tag 'rtc-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "A quiet cycle this time.

   - ds1307: properly handle oscillator failure flags

   - imx-sc: alarm support

   - pcf2123: alarm support, correct offset handling

   - sun6i: add R40 support

   - simplify getting the adapter of an i2c client"

* tag 'rtc-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (37 commits)
  rtc: wm831x: Add IRQF_ONESHOT flag
  rtc: stm32: remove one condition check in stm32_rtc_set_alarm()
  rtc: pcf2123: Fix build error
  rtc: interface: Change type of 'count' from int to u64
  rtc: pcf8563: Clear event flags and disable interrupts before requesting irq
  rtc: pcf8563: Fix interrupt trigger method
  rtc: pcf2123: fix negative offset rounding
  rtc: pcf2123: add alarm support
  rtc: pcf2123: use %ptR
  rtc: pcf2123: port to regmap
  rtc: pcf2123: remove sysfs register view
  rtc: rx8025: simplify getting the adapter of a client
  rtc: rx8010: simplify getting the adapter of a client
  rtc: rv8803: simplify getting the adapter of a client
  rtc: m41t80: simplify getting the adapter of a client
  rtc: fm3130: simplify getting the adapter of a client
  rtc: tegra: Drop MODULE_ALIAS
  rtc: sun6i: Add R40 compatible
  dt-bindings: rtc: sun6i: Add the R40 RTC compatible
  dt-bindings: rtc: Convert Allwinner A31 RTC to a schema
  ...
2019-07-17 10:03:50 -07:00
Maxime Ripard d6624cc750 rtc: sun6i: Add R40 compatible
The R40 has a quite different RTC, with only a single interrupt line, but
two clock outputs. Let's add a compatible.

Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-06-06 12:00:54 +02:00
Thomas Gleixner c942fddf87 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
Based on 3 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version [author] [kishon] [vijay] [abraham]
  [i] [kishon]@[ti] [com] this program is distributed in the hope that
  it will be useful but without any warranty without even the implied
  warranty of merchantability or fitness for a particular purpose see
  the gnu general public license for more details

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version [author] [graeme] [gregory]
  [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
  [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
  [hk] [hemahk]@[ti] [com] this program is distributed in the hope
  that it will be useful but without any warranty without even the
  implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:37 -07:00
Chen-Yu Tsai c56afc1844 rtc: sun6i: Expose internal oscillator through device tree
The bindings have been updated to expose the RTC's internal oscillator,
for some SoCs that have it directly feeding the PRCM block. The changes
include the index 2 for the clock outputs, as well as the clock output
names.

This patch adds the internal oscillator to the list of clocks exposed
through of_clk_add_hw_provider(), and also have the driver optionally
fetch the name of the clock from the device tree if it's available.

Tested-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-06 18:13:46 +01:00
Chen-Yu Tsai 7cd1acaeea rtc: sun6i: Add support for all known pre-H6 variants
There are different variants to the RTC hardware first seen on sun6i
(A31). The differences we care about in this driver are the clock rate
for the internal oscillator, prescalers, and the presence of an external
clock output.

This patch adds support for all the known pre-H6 base compatibles using
the variants data structure previously introduced.

Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Tested-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-06 18:13:44 +01:00
Chen-Yu Tsai 403a3c3dd0 rtc: sun6i: Add support for different variants
Amongst the Allwinner SoCs that have seen some kind of coverage by the
linux-sunxi community, whether it be mainline Linux or U-boot support,
or just available datasheets, most newer chips use the RTC design first
seen in the A31 (sun6i).

Overall there have been some minor differences. This patch covers the
following:

  - average clock rate of the internal RC oscillator
    + presence of fixed and adjustable prescaler for this clock
  - availability of an external (to the SoC) clock output

One major difference regarding the H6 is the 24 MHz crystal is now
routed through the RTC, as a digitally compensated oscillator (DCXO).
This is not covered in this patch and will be supported later.

Other differences are either unrelated to RTC or clock functionality,
such as boot or crypto related registers, or the driver simply doesn't
use the feature in question. One example of the latter is the
calibration function for the RC oscillator. We consider this clock to
be very bad and avoid using it.

Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Tested-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-06 18:13:43 +01:00
Chen-Yu Tsai 459b6ea00a rtc: sun6i: Add default clock name for LOSC
The RTC's main clock, used internally and exported to the rest of the
SoC, is called "LOSC" (low speed oscillator) through the hardware
documentation.

This patch adds a default name for this clock, in case the device tree
does not provide one. This shouldn't happen, but lets play it safe.

Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Tested-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-06 18:13:41 +01:00
Gustavo A. R. Silva 725e0e15f8 rtc: sun6i: Use struct_size() in kzalloc()
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct foo {
	int stuff;
        void *entry[];
};

instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-08-27 23:02:18 +02:00
Michael Trimarchi 09018d4bd7 rtc: sun6i: Fix bit_idx value for clk_register_gate
clk-gate core will take bit_idx through clk_register_gate
and then do clk_gate_ops by using BIT(bit_idx), but rtc-sun6i
is passing bit_idx as BIT(bit_idx) it becomes BIT(BIT(bit_idx)
which is wrong and eventually external gate clock is not enabling.

This patch fixed by passing bit index and the original change
introduced from below commit.
"rtc: sun6i: Add support for the external oscillator gate"
(sha1: 	17ecd24641)

Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
Fixes: 17ecd24641 ("rtc: sun6i: Add support for the external oscillator gate")
Cc: stable@vger.kernel.org
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-05-31 23:02:11 +02:00
Alexandre Belloni 22652ba724 rtc: stop validating rtc_time in .read_time
The RTC core is always calling rtc_valid_tm after the read_time callback.
It is not necessary to call it just before returning from the callback.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-03-02 10:09:58 +01:00
Colin Ian King e998202461 rtc: sun6i: ensure rtc is kfree'd on error
The error return path on clk_data allocation failure does not kfree
the allocated rtc object. Fix this with a kfree of rtc on the error
exit path.

Detected by CoverityScan, CID#1452264 ("Resource Leak")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-12-18 23:05:10 +01:00
Maxime Ripard 17ecd24641 rtc: sun6i: Add support for the external oscillator gate
The RTC can output its 32kHz clock outside of the SoC, for example to clock
a WiFi chip.

Create a new clock that other devices will be able to retrieve, while
maintaining the DT stability by providing a default name for that clock if
clock-output-names doesn't list one.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-09-01 01:10:19 +02:00
Colin Ian King 1a37c34811 rtc: sun6i: ensure clk_data is kfree'd on error
There are two error return paths that do not kfree clk_data and
we end up with a memory leak. Fix these with a kfree error exit
path.

Detected by CoverityScan, CID#1402959 ("Resource Leak")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-07-31 00:17:46 +02:00
Alexey Klimov 319ff835d6 rtc: sun6i: Remove double init of spinlock in sun6i_rtc_clk_init()
Remove double init of spinlock in sun6i_rtc_clk_init()

Fixes: 847b8bf62eb4 ("rtc: sun6i: Expose the 32kHz oscillator")
Signed-off-by: Alexey Klimov <alexey.klimov@arm.com>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-07-31 00:17:46 +02:00
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
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
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
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
Chen-Yu Tsai 9765d2d943 rtc: sun6i: Add sun6i RTC driver
This patch introduces the driver for the RTC in the Allwinner A31 and
A23 SoCs.

Unlike the RTC found in A10/A20 SoCs, which was part of the timer, the
RTC in A31/A23 are a separate hardware block, which also contain a few
controls for the RTC block hardware (a regulator and RTC block GPIO pin
latches), while also having separate interrupts for the alarms.

The hardware is different enough to make a different driver for it.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Reviewed-by: Varka Bhadram <varkabhadram@gmail.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
2014-09-19 12:39:19 +02:00