Merge tag 'rtc-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "Two new drivers this cycle and a significant rework of the CMOS driver
  make the bulk of the changes.

  I also carry powerpc changes with the agreement of Michael.

  New drivers:
   - Sunplus SP7021 RTC
   - Nintendo GameCube, Wii and Wii U RTC

  Driver updates:
   - cmos: refactor UIP handling and presence check, fix century
   - rs5c372: offset correction support, report low voltage
   - rv8803: Epson RX8804 support"

* tag 'rtc-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (33 commits)
  rtc: sunplus: fix return value in sp_rtc_probe()
  rtc: cmos: Evaluate century appropriate
  rtc: gamecube: Fix an IS_ERR() vs NULL check
  rtc: mc146818-lib: fix signedness bug in mc146818_get_time()
  dt-bindings: rtc: qcom-pm8xxx-rtc: update register numbers
  rtc: pxa: fix null pointer dereference
  rtc: ftrtc010: Use platform_get_irq() to get the interrupt
  rtc: Move variable into switch case statement
  rtc: pcf2127: Fix typo in comment
  dt-bindings: rtc: Add Sunplus RTC json-schema
  rtc: Add driver for RTC in Sunplus SP7021
  rtc: rs5c372: fix incorrect oscillation value on r2221tl
  rtc: rs5c372: add offset correction support
  rtc: cmos: avoid UIP when writing alarm time
  rtc: cmos: avoid UIP when reading alarm time
  rtc: mc146818-lib: refactor mc146818_does_rtc_work
  rtc: mc146818-lib: refactor mc146818_get_time
  rtc: mc146818-lib: extract mc146818_avoid_UIP
  rtc: mc146818-lib: fix RTC presence check
  rtc: Check return value from mc146818_get_time()
  ...

Author: torvalds

Documentation/devicetree/bindings/rtc/epson,rx8900.yaml

@@ -15,6 +15,7 @@ allOf:
 properties:
   compatible:
     enum:
+      - epson,rx8804
       - epson,rx8900
       - microcrystal,rv8803
 

Documentation/devicetree/bindings/rtc/qcom-pm8xxx-rtc.yaml

@@ -19,7 +19,14 @@ properties:
       - qcom,pmk8350-rtc
 
   reg:
-    maxItems: 1
+    minItems: 1
+    maxItems: 2
+
+  reg-names:
+    minItems: 1
+    items:
+      - const: rtc
+      - const: alarm
 
   interrupts:
     maxItems: 1

Documentation/devicetree/bindings/rtc/sunplus,sp7021-rtc.yaml

@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+# Copyright (C) Sunplus Co., Ltd. 2021
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/rtc/sunplus,sp7021-rtc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Sunplus SP7021 Real Time Clock controller
+
+maintainers:
+  - Vincent Shih <vincent.sunplus@gmail.com>
+
+properties:
+  compatible:
+    const: sunplus,sp7021-rtc
+
+  reg:
+    maxItems: 1
+
+  reg-names:
+    items:
+      - const: rtc
+
+  clocks:
+    maxItems: 1
+
+  resets:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - reg-names
+  - clocks
+  - resets
+  - interrupts
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    rtc: serial@9c003a00 {
+        compatible = "sunplus,sp7021-rtc";
+        reg = <0x9c003a00 0x80>;
+        reg-names = "rtc";
+        clocks = <&clkc 0x12>;
+        resets = <&rstc 0x02>;
+        interrupt-parent = <&intc>;
+        interrupts = <163 IRQ_TYPE_EDGE_RISING>;
+    };
+...

MAINTAINERS

@@ -18491,6 +18491,13 @@ L:	netdev@vger.kernel.org
 S:	Maintained
 F:	drivers/net/ethernet/dlink/sundance.c
 
+SUNPLUS RTC DRIVER
+M:	Vincent Shih <vincent.sunplus@gmail.com>
+L:	linux-rtc@vger.kernel.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/rtc/sunplus,sp7021-rtc.yaml
+F:	drivers/rtc/rtc-sunplus.c
+
 SUPERH
 M:	Yoshinori Sato <ysato@users.sourceforge.jp>
 M:	Rich Felker <dalias@libc.org>

arch/alpha/kernel/rtc.c

@@ -80,7 +80,12 @@ init_rtc_epoch(void)
 static int
 alpha_rtc_read_time(struct device *dev, struct rtc_time *tm)
 {
-	mc146818_get_time(tm);
+	int ret = mc146818_get_time(tm);
+
+	if (ret < 0) {
+		dev_err_ratelimited(dev, "unable to read current time\n");
+		return ret;
+	}
 
 	/* Adjust for non-default epochs.  It's easier to depend on the
 	   generic __get_rtc_time and adjust the epoch here than create

arch/powerpc/boot/dts/wii.dts

@@ -168,6 +168,11 @@
 			interrupts = <14>;
 		};
 
+		srnprot@d800060 {
+			compatible = "nintendo,hollywood-srnprot";
+			reg = <0x0d800060 0x4>;
+		};
+
 		GPIO: gpio@d8000c0 {
 			#gpio-cells = <2>;
 			compatible = "nintendo,hollywood-gpio";

arch/powerpc/configs/gamecube_defconfig

@@ -68,7 +68,7 @@ CONFIG_SND_SEQUENCER=y
 CONFIG_SND_SEQUENCER_OSS=y
 # CONFIG_USB_SUPPORT is not set
 CONFIG_RTC_CLASS=y
-CONFIG_RTC_DRV_GENERIC=y
+CONFIG_RTC_DRV_GAMECUBE=y
 CONFIG_EXT2_FS=y
 CONFIG_EXT4_FS=y
 CONFIG_ISO9660_FS=y

arch/powerpc/configs/wii_defconfig

@@ -98,7 +98,7 @@ CONFIG_LEDS_TRIGGERS=y
 CONFIG_LEDS_TRIGGER_HEARTBEAT=y
 CONFIG_LEDS_TRIGGER_PANIC=y
 CONFIG_RTC_CLASS=y
-CONFIG_RTC_DRV_GENERIC=y
+CONFIG_RTC_DRV_GAMECUBE=y
 CONFIG_NVMEM_NINTENDO_OTP=y
 CONFIG_EXT2_FS=y
 CONFIG_EXT4_FS=y

arch/x86/kernel/hpet.c

@@ -1435,8 +1435,12 @@ irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id)
 	hpet_rtc_timer_reinit();
 	memset(&curr_time, 0, sizeof(struct rtc_time));
 
-	if (hpet_rtc_flags & (RTC_UIE | RTC_AIE))
-		mc146818_get_time(&curr_time);
+	if (hpet_rtc_flags & (RTC_UIE | RTC_AIE)) {
+		if (unlikely(mc146818_get_time(&curr_time) < 0)) {
+			pr_err_ratelimited("unable to read current time from RTC\n");
+			return IRQ_HANDLED;
+		}
+	}
 
 	if (hpet_rtc_flags & RTC_UIE &&
 	    curr_time.tm_sec != hpet_prev_update_sec) {

drivers/base/power/trace.c

@@ -120,7 +120,11 @@ static unsigned int read_magic_time(void)
 	struct rtc_time time;
 	unsigned int val;
 
-	mc146818_get_time(&time);
+	if (mc146818_get_time(&time) < 0) {
+		pr_err("Unable to read current time from RTC\n");
+		return 0;
+	}
+
 	pr_info("RTC time: %ptRt, date: %ptRd\n", &time, &time);
 	val = time.tm_year;				/* 100 years */
 	if (val > 100)