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path: root/drivers/rtc/rtc-sun6i.c
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2017-02-12rtc: sun6i: Fix return value check in sun6i_rtc_clk_init()Wei Yongjun1-1/+1
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>
2017-02-01rtc: sun6i: Fix compatibility with old DT bindingChen-Yu Tsai1-3/+3
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>
2017-02-01rtc: sun6i: Switch to devm_rtc_device_registerMaxime Ripard1-12/+2
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>
2017-02-01rtc: sun6i: Expose the 32kHz oscillatorMaxime Ripard1-13/+133
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>
2017-02-01rtc: sun6i: Switch to the external oscillatorMaxime Ripard1-0/+6
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: 9765d2d94309 ("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>
2017-02-01rtc: sun6i: Add some lockingMaxime Ripard1-2/+15
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>
2017-01-24rtc: sun6i: Disable the build as a moduleMaxime Ripard1-6/+1
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>
2014-09-19rtc: sun6i: Add sun6i RTC driverChen-Yu Tsai1-0/+447
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>