diff options
Diffstat (limited to 'target/linux/brcm2708/patches-4.19/950-0165-Revert-rtc-pcf8523-properly-handle-oscillator-stop-b.patch')
| -rw-r--r-- | target/linux/brcm2708/patches-4.19/950-0165-Revert-rtc-pcf8523-properly-handle-oscillator-stop-b.patch | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.19/950-0165-Revert-rtc-pcf8523-properly-handle-oscillator-stop-b.patch b/target/linux/brcm2708/patches-4.19/950-0165-Revert-rtc-pcf8523-properly-handle-oscillator-stop-b.patch new file mode 100644 index 0000000000..b9a4f52e5a --- /dev/null +++ b/target/linux/brcm2708/patches-4.19/950-0165-Revert-rtc-pcf8523-properly-handle-oscillator-stop-b.patch @@ -0,0 +1,56 @@ +From 0557d41d861b8c214b3472749482efdc71363dbb 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 | 25 ++++++++++++++++++++++--- + 1 file changed, 22 insertions(+), 3 deletions(-) + +--- a/drivers/rtc/rtc-pcf8523.c ++++ b/drivers/rtc/rtc-pcf8523.c +@@ -212,8 +212,28 @@ static int pcf8523_rtc_read_time(struct + if (err < 0) + return err; + +- if (regs[0] & REG_SECONDS_OS) +- return -EINVAL; ++ if (regs[0] & REG_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] &= ~REG_SECONDS_OS; ++ ++ err = pcf8523_write(client, REG_SECONDS, regs[0]); ++ if (err < 0) ++ return err; ++ ++ err = pcf8523_read(client, REG_SECONDS, ®s[0]); ++ if (err < 0) ++ return err; ++ ++ if (regs[0] & REG_SECONDS_OS) ++ return -EAGAIN; ++ } + + tm->tm_sec = bcd2bin(regs[0] & 0x7f); + tm->tm_min = bcd2bin(regs[1] & 0x7f); +@@ -249,7 +269,6 @@ static int pcf8523_rtc_set_time(struct d + return err; + + regs[0] = REG_SECONDS; +- /* This will purposely overwrite REG_SECONDS_OS */ + regs[1] = bin2bcd(tm->tm_sec); + regs[2] = bin2bcd(tm->tm_min); + regs[3] = bin2bcd(tm->tm_hour); |