diff --git a/drivers/rtc/rtc-isl1208.c b/drivers/rtc/rtc-isl1208.c index 206f96b90f58..6877e2f3bde6 100644 --- a/drivers/rtc/rtc-isl1208.c +++ b/drivers/rtc/rtc-isl1208.c @@ -7,6 +7,7 @@ #include #include +#include #include #include #include @@ -628,6 +629,18 @@ isl1208_rtc_interrupt(int irq, void *data) struct isl1208_state *isl1208 = i2c_get_clientdata(client); int handled = 0, sr, err; + if (!isl1208->config->has_tamper) { + /* + * The INT# output is pulled low 250ms after the alarm is + * triggered. After the INT# output is pulled low, it is low for + * at least 250ms, even if the correct action is taken to clear + * it. It is impossible to clear ALM if it is still active. The + * host must wait for the RTC to progress past the alarm time + * plus the 250ms delay before clearing ALM. + */ + msleep(250); + } + /* * I2C reads get NAK'ed if we read straight away after an interrupt? * Using a mdelay/msleep didn't seem to help either, so we work around