diff --git a/drivers/rtc/rtc-twl.c b/drivers/rtc/rtc-twl.c index 4c2c6df2a9e..258abeabf62 100644 --- a/drivers/rtc/rtc-twl.c +++ b/drivers/rtc/rtc-twl.c @@ -112,6 +112,7 @@ static const u8 twl6030_rtc_reg_map[] = { #define BIT_RTC_CTRL_REG_TEST_MODE_M 0x10 #define BIT_RTC_CTRL_REG_SET_32_COUNTER_M 0x20 #define BIT_RTC_CTRL_REG_GET_TIME_M 0x40 +#define BIT_RTC_CTRL_REG_RTC_V_OPT 0x80 /* RTC_STATUS_REG bitfields */ #define BIT_RTC_STATUS_REG_RUN_M 0x02 @@ -235,25 +236,57 @@ static int twl_rtc_read_time(struct device *dev, struct rtc_time *tm) unsigned char rtc_data[ALL_TIME_REGS + 1]; int ret; u8 save_control; + u8 rtc_control; ret = twl_rtc_read_u8(&save_control, REG_RTC_CTRL_REG); - if (ret < 0) + if (ret < 0) { + dev_err(dev, "%s: reading CTRL_REG, error %d\n", __func__, ret); return ret; + } + /* for twl6030/32 make sure BIT_RTC_CTRL_REG_GET_TIME_M is clear */ + if (twl_class_is_6030()) { + if (save_control & BIT_RTC_CTRL_REG_GET_TIME_M) { + save_control &= ~BIT_RTC_CTRL_REG_GET_TIME_M; + ret = twl_rtc_write_u8(save_control, REG_RTC_CTRL_REG); + if (ret < 0) { + dev_err(dev, "%s clr GET_TIME, error %d\n", + __func__, ret); + return ret; + } + } + } - save_control |= BIT_RTC_CTRL_REG_GET_TIME_M; + /* Copy RTC counting registers to static registers or latches */ + rtc_control = save_control | BIT_RTC_CTRL_REG_GET_TIME_M; - ret = twl_rtc_write_u8(save_control, REG_RTC_CTRL_REG); - if (ret < 0) + /* for twl6030/32 enable read access to static shadowed registers */ + if (twl_class_is_6030()) + rtc_control |= BIT_RTC_CTRL_REG_RTC_V_OPT; + + ret = twl_rtc_write_u8(rtc_control, REG_RTC_CTRL_REG); + if (ret < 0) { + dev_err(dev, "%s: writing CTRL_REG, error %d\n", __func__, ret); return ret; + } ret = twl_i2c_read(TWL_MODULE_RTC, rtc_data, (rtc_reg_map[REG_SECONDS_REG]), ALL_TIME_REGS); if (ret < 0) { - dev_err(dev, "rtc_read_time error %d\n", ret); + dev_err(dev, "%s: reading data, error %d\n", __func__, ret); return ret; } + /* for twl6030 restore original state of rtc control register */ + if (twl_class_is_6030()) { + ret = twl_rtc_write_u8(save_control, REG_RTC_CTRL_REG); + if (ret < 0) { + dev_err(dev, "%s: restore CTRL_REG, error %d\n", + __func__, ret); + return ret; + } + } + tm->tm_sec = bcd2bin(rtc_data[0]); tm->tm_min = bcd2bin(rtc_data[1]); tm->tm_hour = bcd2bin(rtc_data[2]);