Re: [PATCH 05/33] ARM: dts: exynos: Correct S3C RTC bindings and enable it in Trats
From: Marek Szyprowski <m.szyprowski@samsung.com>
Date: 2020-08-31 09:49:32
Also in:
linux-arm-kernel, linux-samsung-soc, lkml
On 30.08.2020 15:51, Krzysztof Kozlowski wrote:
The S3C RTC requires 32768 Hz clock as input which is provided by PMIC (Maxim MAX8997). However there is no clock provided for the PMIC and the driver registers the clock as regulator. This is an old driver which will not be updated so add a workaround: 1. Enable the "clock" regulator in PMIC, 2. Add a fixed-clock to fill missing clock phandle reference in S3C RTC. This allows to enable the S3C RTC and fixes dtbs_check warnings: arch/arm/boot/dts/exynos4210-trats.dt.yaml: rtc@10070000: clocks: [[5, 346]] is too short arch/arm/boot/dts/exynos4210-trats.dt.yaml: rtc@10070000: clock-names: ['rtc'] is too short Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Confirmed, this workaround enables s3c-rtc driver operation on this board. Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
quoted hunk ↗ jump to hunk
--- arch/arm/boot/dts/exynos4210-trats.dts | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+)diff --git a/arch/arm/boot/dts/exynos4210-trats.dts b/arch/arm/boot/dts/exynos4210-trats.dts index 5cc96f04a4fa..634f009b622e 100644 --- a/arch/arm/boot/dts/exynos4210-trats.dts +++ b/arch/arm/boot/dts/exynos4210-trats.dts@@ -132,6 +132,13 @@ compatible = "samsung,clock-xusbxti"; clock-frequency = <24000000>; }; + + pmic_ap_clk: pmic-ap-clk { + /* Workaround for missing clock on max8997 PMIC */ + compatible = "fixed-clock"; + #clock-cells = <0>; + clock-frequency = <32768>; + }; }; thermal-zones {@@ -444,10 +451,21 @@ regulator-name = "SAFEOUT2"; regulator-boot-on; }; + + EN32KHZ_AP { + regulator-name = "EN32KHZ_AP"; + regulator-always-on; + }; }; }; }; +&rtc { + status = "okay"; + clocks = <&clock CLK_RTC>, <&pmic_ap_clk>; + clock-names = "rtc", "rtc_src"; +}; + &sdhci_0 { bus-width = <8>; non-removable;
Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland