diff options
Diffstat (limited to 'drivers/rtc/rtc-pcf2127.c')
| -rw-r--r-- | drivers/rtc/rtc-pcf2127.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-pcf2127.c b/drivers/rtc/rtc-pcf2127.c index 8d6eda455d81..3ec87d320766 100644 --- a/drivers/rtc/rtc-pcf2127.c +++ b/drivers/rtc/rtc-pcf2127.c @@ -25,11 +25,18 @@ /* Control register 1 */ #define PCF2127_REG_CTRL1 0x00 +#define PCF2127_BIT_CTRL1_TSF1 BIT(4) /* Control register 2 */ #define PCF2127_REG_CTRL2 0x01 +#define PCF2127_BIT_CTRL2_TSIE BIT(2) +#define PCF2127_BIT_CTRL2_TSF2 BIT(5) /* Control register 3 */ #define PCF2127_REG_CTRL3 0x02 +#define PCF2127_BIT_CTRL3_BLIE BIT(0) +#define PCF2127_BIT_CTRL3_BIE BIT(1) #define PCF2127_BIT_CTRL3_BLF BIT(2) +#define PCF2127_BIT_CTRL3_BF BIT(3) +#define PCF2127_BIT_CTRL3_BTSE BIT(4) /* Time and date registers */ #define PCF2127_REG_SC 0x03 #define PCF2127_BIT_SC_OSF BIT(7) @@ -46,6 +53,16 @@ #define PCF2127_BIT_WD_CTL_CD0 BIT(6) #define PCF2127_BIT_WD_CTL_CD1 BIT(7) #define PCF2127_REG_WD_VAL 0x11 +/* Tamper timestamp registers */ +#define PCF2127_REG_TS_CTRL 0x12 +#define PCF2127_BIT_TS_CTRL_TSOFF BIT(6) +#define PCF2127_BIT_TS_CTRL_TSM BIT(7) +#define PCF2127_REG_TS_SC 0x13 +#define PCF2127_REG_TS_MN 0x14 +#define PCF2127_REG_TS_HR 0x15 +#define PCF2127_REG_TS_DM 0x16 +#define PCF2127_REG_TS_MO 0x17 +#define PCF2127_REG_TS_YR 0x18 /* * RAM registers * PCF2127 has 512 bytes general-purpose static RAM (SRAM) that is @@ -305,6 +322,97 @@ static const struct watchdog_ops pcf2127_watchdog_ops = { .set_timeout = pcf2127_wdt_set_timeout, }; +/* sysfs interface */ + +static ssize_t timestamp0_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct pcf2127 *pcf2127 = dev_get_drvdata(dev->parent); + int ret; + + ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_CTRL1, + PCF2127_BIT_CTRL1_TSF1, 0); + if (ret) { + dev_err(dev, "%s: update ctrl1 ret=%d\n", __func__, ret); + return ret; + } + + ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_CTRL2, + PCF2127_BIT_CTRL2_TSF2, 0); + if (ret) { + dev_err(dev, "%s: update ctrl2 ret=%d\n", __func__, ret); + return ret; + } + + ret = pcf2127_wdt_active_ping(&pcf2127->wdd); + if (ret) + return ret; + + return count; +}; + +static ssize_t timestamp0_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct pcf2127 *pcf2127 = dev_get_drvdata(dev->parent); + struct rtc_time tm; + int ret; + unsigned char data[25]; + + ret = regmap_bulk_read(pcf2127->regmap, PCF2127_REG_CTRL1, data, + sizeof(data)); + if (ret) { + dev_err(dev, "%s: read error ret=%d\n", __func__, ret); + return ret; + } + + dev_dbg(dev, + "%s: raw data is cr1=%02x, cr2=%02x, cr3=%02x, ts_sc=%02x, " + "ts_mn=%02x, ts_hr=%02x, ts_dm=%02x, ts_mo=%02x, ts_yr=%02x\n", + __func__, data[PCF2127_REG_CTRL1], data[PCF2127_REG_CTRL2], + data[PCF2127_REG_CTRL3], data[PCF2127_REG_TS_SC], + data[PCF2127_REG_TS_MN], data[PCF2127_REG_TS_HR], + data[PCF2127_REG_TS_DM], data[PCF2127_REG_TS_MO], + data[PCF2127_REG_TS_YR]); + + ret = pcf2127_wdt_active_ping(&pcf2127->wdd); + if (ret) + return ret; + + if (!(data[PCF2127_REG_CTRL1] & PCF2127_BIT_CTRL1_TSF1) && + !(data[PCF2127_REG_CTRL2] & PCF2127_BIT_CTRL2_TSF2)) + return 0; + + tm.tm_sec = bcd2bin(data[PCF2127_REG_TS_SC] & 0x7F); + tm.tm_min = bcd2bin(data[PCF2127_REG_TS_MN] & 0x7F); + tm.tm_hour = bcd2bin(data[PCF2127_REG_TS_HR] & 0x3F); + tm.tm_mday = bcd2bin(data[PCF2127_REG_TS_DM] & 0x3F); + /* TS_MO register (month) value range: 1-12 */ + tm.tm_mon = bcd2bin(data[PCF2127_REG_TS_MO] & 0x1F) - 1; + tm.tm_year = bcd2bin(data[PCF2127_REG_TS_YR]); + if (tm.tm_year < 70) + tm.tm_year += 100; /* assume we are in 1970...2069 */ + + ret = rtc_valid_tm(&tm); + if (ret) + return ret; + + return sprintf(buf, "%llu\n", + (unsigned long long)rtc_tm_to_time64(&tm)); +}; + +static DEVICE_ATTR_RW(timestamp0); + +static struct attribute *pcf2127_attrs[] = { + &dev_attr_timestamp0.attr, + NULL +}; + +static const struct attribute_group pcf2127_attr_group = { + .attrs = pcf2127_attrs, +}; + static int pcf2127_probe(struct device *dev, struct regmap *regmap, const char *name, bool has_nvmem) { @@ -371,6 +479,58 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap, if (ret) return ret; + /* + * Disable battery low/switch-over timestamp and interrupts. + * Clear battery interrupt flags which can block new trigger events. + * Note: This is the default chip behaviour but added to ensure + * correct tamper timestamp and interrupt function. + */ + ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_CTRL3, + PCF2127_BIT_CTRL3_BTSE | + PCF2127_BIT_CTRL3_BF | + PCF2127_BIT_CTRL3_BIE | + PCF2127_BIT_CTRL3_BLIE, 0); + if (ret) { + dev_err(dev, "%s: interrupt config (ctrl3) failed\n", + __func__); + return ret; + } + + /* + * Enable timestamp function and store timestamp of first trigger + * event until TSF1 and TFS2 interrupt flags are cleared. + */ + ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_TS_CTRL, + PCF2127_BIT_TS_CTRL_TSOFF | + PCF2127_BIT_TS_CTRL_TSM, + PCF2127_BIT_TS_CTRL_TSM); + if (ret) { + dev_err(dev, "%s: tamper detection config (ts_ctrl) failed\n", + __func__); + return ret; + } + + /* + * Enable interrupt generation when TSF1 or TSF2 timestamp flags + * are set. Interrupt signal is an open-drain output and can be + * left floating if unused. + */ + ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_CTRL2, + PCF2127_BIT_CTRL2_TSIE, + PCF2127_BIT_CTRL2_TSIE); + if (ret) { + dev_err(dev, "%s: tamper detection config (ctrl2) failed\n", + __func__); + return ret; + } + + ret = rtc_add_group(pcf2127->rtc, &pcf2127_attr_group); + if (ret) { + dev_err(dev, "%s: tamper sysfs registering failed\n", + __func__); + return ret; + } + return rtc_register_device(pcf2127->rtc); } |