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authorBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>2018-09-26 16:54:31 +0300
committerBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>2018-09-26 16:54:31 +0300
commitaaccf3c97418f169afdbb5855e9cbcbda34e90fd (patch)
tree5d4207e67958bdbc23288cf30178692f5534e1a0 /drivers/rtc/rtc-armada38x.c
parentf39684524b391c5a7ed0ac44db4fec3357af1c5d (diff)
parent6bf4ca7fbc85d80446ac01c0d1d77db4d91a6d84 (diff)
downloadlinux-aaccf3c97418f169afdbb5855e9cbcbda34e90fd.tar.xz
Merge tag 'v4.19-rc5' of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into fbdev-for-next
Sync with upstream (which now contains fbdev-v4.19 changes) to prepare a base for fbdev-v4.20 changes.
Diffstat (limited to 'drivers/rtc/rtc-armada38x.c')
-rw-r--r--drivers/rtc/rtc-armada38x.c23
1 files changed, 23 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-armada38x.c b/drivers/rtc/rtc-armada38x.c
index 1e4978c96ffd..bde53c8ccee2 100644
--- a/drivers/rtc/rtc-armada38x.c
+++ b/drivers/rtc/rtc-armada38x.c
@@ -30,6 +30,8 @@
#define RTC_IRQ_FREQ_1HZ BIT(2)
#define RTC_CCR 0x18
#define RTC_CCR_MODE BIT(15)
+#define RTC_CONF_TEST 0x1C
+#define RTC_NOMINAL_TIMING BIT(13)
#define RTC_TIME 0xC
#define RTC_ALARM1 0x10
@@ -75,6 +77,7 @@ struct armada38x_rtc {
void __iomem *regs_soc;
spinlock_t lock;
int irq;
+ bool initialized;
struct value_to_freq *val_to_freq;
struct armada38x_rtc_data *data;
};
@@ -226,6 +229,23 @@ static int armada38x_rtc_read_time(struct device *dev, struct rtc_time *tm)
return 0;
}
+static void armada38x_rtc_reset(struct armada38x_rtc *rtc)
+{
+ u32 reg;
+
+ reg = rtc->data->read_rtc_reg(rtc, RTC_CONF_TEST);
+ /* If bits [7:0] are non-zero, assume RTC was uninitialized */
+ if (reg & 0xff) {
+ rtc_delayed_write(0, rtc, RTC_CONF_TEST);
+ msleep(500); /* Oscillator startup time */
+ rtc_delayed_write(0, rtc, RTC_TIME);
+ rtc_delayed_write(SOC_RTC_ALARM1 | SOC_RTC_ALARM2, rtc,
+ RTC_STATUS);
+ rtc_delayed_write(RTC_NOMINAL_TIMING, rtc, RTC_CCR);
+ }
+ rtc->initialized = true;
+}
+
static int armada38x_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct armada38x_rtc *rtc = dev_get_drvdata(dev);
@@ -237,6 +257,9 @@ static int armada38x_rtc_set_time(struct device *dev, struct rtc_time *tm)
if (ret)
goto out;
+ if (!rtc->initialized)
+ armada38x_rtc_reset(rtc);
+
spin_lock_irqsave(&rtc->lock, flags);
rtc_delayed_write(time, rtc, RTC_TIME);
spin_unlock_irqrestore(&rtc->lock, flags);