diff options
Diffstat (limited to 'drivers/rtc/rtc-ds1307.c')
| -rw-r--r-- | drivers/rtc/rtc-ds1307.c | 145 |
1 files changed, 144 insertions, 1 deletions
diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c index 4b2b4627daeb..74b31dce484f 100644 --- a/drivers/rtc/rtc-ds1307.c +++ b/drivers/rtc/rtc-ds1307.c @@ -114,6 +114,20 @@ enum ds_type { # define RX8025_BIT_VDET 0x40 # define RX8025_BIT_XST 0x20 +#define M41TXX_REG_CONTROL 0x07 +# define M41TXX_BIT_OUT BIT(7) +# define M41TXX_BIT_FT BIT(6) +# define M41TXX_BIT_CALIB_SIGN BIT(5) +# define M41TXX_M_CALIBRATION GENMASK(4, 0) + +/* negative offset step is -2.034ppm */ +#define M41TXX_NEG_OFFSET_STEP_PPB 2034 +/* positive offset step is +4.068ppm */ +#define M41TXX_POS_OFFSET_STEP_PPB 4068 +/* Min and max values supported with 'offset' interface by M41TXX */ +#define M41TXX_MIN_OFFSET ((-31) * M41TXX_NEG_OFFSET_STEP_PPB) +#define M41TXX_MAX_OFFSET ((31) * M41TXX_POS_OFFSET_STEP_PPB) + struct ds1307 { enum ds_type type; unsigned long flags; @@ -146,6 +160,9 @@ struct chip_desc { static int ds1307_get_time(struct device *dev, struct rtc_time *t); static int ds1307_set_time(struct device *dev, struct rtc_time *t); +static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t); +static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t); +static int ds1307_alarm_irq_enable(struct device *dev, unsigned int enabled); static u8 do_trickle_setup_ds1339(struct ds1307 *, u32 ohms, bool diode); static irqreturn_t rx8130_irq(int irq, void *dev_id); static int rx8130_read_alarm(struct device *dev, struct rtc_wkalrm *t); @@ -155,6 +172,8 @@ static irqreturn_t mcp794xx_irq(int irq, void *dev_id); static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t); static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t); static int mcp794xx_alarm_irq_enable(struct device *dev, unsigned int enabled); +static int m41txx_rtc_read_offset(struct device *dev, long *offset); +static int m41txx_rtc_set_offset(struct device *dev, long offset); static const struct rtc_class_ops rx8130_rtc_ops = { .read_time = ds1307_get_time, @@ -172,6 +191,16 @@ static const struct rtc_class_ops mcp794xx_rtc_ops = { .alarm_irq_enable = mcp794xx_alarm_irq_enable, }; +static const struct rtc_class_ops m41txx_rtc_ops = { + .read_time = ds1307_get_time, + .set_time = ds1307_set_time, + .read_alarm = ds1337_read_alarm, + .set_alarm = ds1337_set_alarm, + .alarm_irq_enable = ds1307_alarm_irq_enable, + .read_offset = m41txx_rtc_read_offset, + .set_offset = m41txx_rtc_set_offset, +}; + static const struct chip_desc chips[last_ds_type] = { [ds_1307] = { .nvram_offset = 8, @@ -228,10 +257,17 @@ static const struct chip_desc chips[last_ds_type] = { .irq_handler = rx8130_irq, .rtc_ops = &rx8130_rtc_ops, }, + [m41t0] = { + .rtc_ops = &m41txx_rtc_ops, + }, + [m41t00] = { + .rtc_ops = &m41txx_rtc_ops, + }, [m41t11] = { /* this is battery backed SRAM */ .nvram_offset = 8, .nvram_size = 56, + .rtc_ops = &m41txx_rtc_ops, }, [mcp794xx] = { .alarm = 1, @@ -973,6 +1009,110 @@ static int mcp794xx_alarm_irq_enable(struct device *dev, unsigned int enabled) enabled ? MCP794XX_BIT_ALM0_EN : 0); } +static int m41txx_rtc_read_offset(struct device *dev, long *offset) +{ + struct ds1307 *ds1307 = dev_get_drvdata(dev); + unsigned int ctrl_reg; + u8 val; + + regmap_read(ds1307->regmap, M41TXX_REG_CONTROL, &ctrl_reg); + + val = ctrl_reg & M41TXX_M_CALIBRATION; + + /* check if positive */ + if (ctrl_reg & M41TXX_BIT_CALIB_SIGN) + *offset = (val * M41TXX_POS_OFFSET_STEP_PPB); + else + *offset = -(val * M41TXX_NEG_OFFSET_STEP_PPB); + + return 0; +} + +static int m41txx_rtc_set_offset(struct device *dev, long offset) +{ + struct ds1307 *ds1307 = dev_get_drvdata(dev); + unsigned int ctrl_reg; + + if ((offset < M41TXX_MIN_OFFSET) || (offset > M41TXX_MAX_OFFSET)) + return -ERANGE; + + if (offset >= 0) { + ctrl_reg = DIV_ROUND_CLOSEST(offset, + M41TXX_POS_OFFSET_STEP_PPB); + ctrl_reg |= M41TXX_BIT_CALIB_SIGN; + } else { + ctrl_reg = DIV_ROUND_CLOSEST(abs(offset), + M41TXX_NEG_OFFSET_STEP_PPB); + } + + return regmap_update_bits(ds1307->regmap, M41TXX_REG_CONTROL, + M41TXX_M_CALIBRATION | M41TXX_BIT_CALIB_SIGN, + ctrl_reg); +} + +static ssize_t frequency_test_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct ds1307 *ds1307 = dev_get_drvdata(dev->parent); + bool freq_test_en; + int ret; + + ret = kstrtobool(buf, &freq_test_en); + if (ret) { + dev_err(dev, "Failed to store RTC Frequency Test attribute\n"); + return ret; + } + + regmap_update_bits(ds1307->regmap, M41TXX_REG_CONTROL, M41TXX_BIT_FT, + freq_test_en ? M41TXX_BIT_FT : 0); + + return count; +} + +static ssize_t frequency_test_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct ds1307 *ds1307 = dev_get_drvdata(dev->parent); + unsigned int ctrl_reg; + + regmap_read(ds1307->regmap, M41TXX_REG_CONTROL, &ctrl_reg); + + return scnprintf(buf, PAGE_SIZE, (ctrl_reg & M41TXX_BIT_FT) ? "on\n" : + "off\n"); +} + +static DEVICE_ATTR_RW(frequency_test); + +static struct attribute *rtc_freq_test_attrs[] = { + &dev_attr_frequency_test.attr, + NULL, +}; + +static const struct attribute_group rtc_freq_test_attr_group = { + .attrs = rtc_freq_test_attrs, +}; + +static int ds1307_add_frequency_test(struct ds1307 *ds1307) +{ + int err; + + switch (ds1307->type) { + case m41t0: + case m41t00: + case m41t11: + err = rtc_add_group(ds1307->rtc, &rtc_freq_test_attr_group); + if (err) + return err; + break; + default: + break; + } + + return 0; +} + /*----------------------------------------------------------------------*/ static int ds1307_nvram_read(void *priv, unsigned int offset, void *val, @@ -1384,7 +1524,6 @@ static void ds1307_clks_register(struct ds1307 *ds1307) static const struct regmap_config regmap_config = { .reg_bits = 8, .val_bits = 8, - .max_register = 0x9, }; static int ds1307_probe(struct i2c_client *client, @@ -1711,6 +1850,10 @@ read_rtc: } ds1307->rtc->ops = chip->rtc_ops ?: &ds13xx_rtc_ops; + err = ds1307_add_frequency_test(ds1307); + if (err) + return err; + err = rtc_register_device(ds1307->rtc); if (err) return err; |