20ea6adbf1
Build system: x86_64 Build-tested: bcm2708, bcm2709, bcm2710, bcm2711 Run-tested: bcm2708/RPiB+, bcm2709/RPi3B, bcm2710/RPi3B, bcm2711/RPi4B Signed-off-by: Marty Jones <mj8263788@gmail.com> Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
49 lines
1.4 KiB
Diff
49 lines
1.4 KiB
Diff
From 39869587dac09c9e738960ccdf01e1dc62a906f7 Mon Sep 17 00:00:00 2001
|
|
From: Phil Elwell <phil@raspberrypi.org>
|
|
Date: Mon, 29 Oct 2018 14:45:45 +0000
|
|
Subject: [PATCH] Revert "rtc: pcf8523: properly handle oscillator stop
|
|
bit"
|
|
|
|
This reverts commit ede44c908d44b166a5b6bd7caacd105c2ff5a70f.
|
|
|
|
See: https://github.com/raspberrypi/firmware/issues/1065
|
|
|
|
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
|
|
---
|
|
drivers/rtc/rtc-pcf8523.c | 24 ++++++++++++++++++++++--
|
|
1 file changed, 22 insertions(+), 2 deletions(-)
|
|
|
|
--- a/drivers/rtc/rtc-pcf8523.c
|
|
+++ b/drivers/rtc/rtc-pcf8523.c
|
|
@@ -242,8 +242,28 @@ static int pcf8523_rtc_read_time(struct
|
|
if (err < 0)
|
|
return err;
|
|
|
|
- if (regs[0] & PCF8523_SECONDS_OS)
|
|
- return -EINVAL;
|
|
+ if (regs[0] & PCF8523_SECONDS_OS) {
|
|
+ /*
|
|
+ * If the oscillator was stopped, try to clear the flag. Upon
|
|
+ * power-up the flag is always set, but if we cannot clear it
|
|
+ * the oscillator isn't running properly for some reason. The
|
|
+ * sensible thing therefore is to return an error, signalling
|
|
+ * that the clock cannot be assumed to be correct.
|
|
+ */
|
|
+
|
|
+ regs[0] &= ~PCF8523_SECONDS_OS;
|
|
+
|
|
+ err = pcf8523_write(client, PCF8523_REG_SECONDS, regs[0]);
|
|
+ if (err < 0)
|
|
+ return err;
|
|
+
|
|
+ err = pcf8523_read(client, PCF8523_REG_SECONDS, ®s[0]);
|
|
+ if (err < 0)
|
|
+ return err;
|
|
+
|
|
+ if (regs[0] & PCF8523_SECONDS_OS)
|
|
+ return -EAGAIN;
|
|
+ }
|
|
|
|
tm->tm_sec = bcd2bin(regs[0] & 0x7f);
|
|
tm->tm_min = bcd2bin(regs[1] & 0x7f);
|