diff options
Diffstat (limited to 'drivers/rtc/rtc-ds1307.c')
| -rw-r--r-- | drivers/rtc/rtc-ds1307.c | 58 |
1 files changed, 53 insertions, 5 deletions
diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c index 1f7e8aefc1eb..69994ae577b7 100644 --- a/drivers/rtc/rtc-ds1307.c +++ b/drivers/rtc/rtc-ds1307.c @@ -121,6 +121,9 @@ enum ds_type { #define RX8130_REG_FLAG_AF BIT(3) #define RX8130_REG_CONTROL0 0x1e #define RX8130_REG_CONTROL0_AIE BIT(3) +#define RX8130_REG_CONTROL1 0x1f +#define RX8130_REG_CONTROL1_INIEN BIT(4) +#define RX8130_REG_CONTROL1_CHGEN BIT(5) #define MCP794XX_REG_CONTROL 0x07 # define MCP794XX_BIT_ALM0_EN 0x10 @@ -180,6 +183,15 @@ struct chip_desc { u16 trickle_charger_reg; u8 (*do_trickle_setup)(struct ds1307 *, u32, bool); + /* Does the RTC require trickle-resistor-ohms to select the value of + * the resistor between Vcc and Vbackup? + */ + bool requires_trickle_resistor; + /* Some RTC's batteries and supercaps were charged by default, others + * allow charging but were not configured previously to do so. + * Remember this behavior to stay backwards compatible. + */ + bool charge_default; }; static const struct chip_desc chips[last_ds_type]; @@ -490,6 +502,8 @@ static u8 do_trickle_setup_ds1339(struct ds1307 *ds1307, u32 ohms, bool diode) u8 setup = (diode) ? DS1307_TRICKLE_CHARGER_DIODE : DS1307_TRICKLE_CHARGER_NO_DIODE; + setup |= DS13XX_TRICKLE_CHARGER_MAGIC; + switch (ohms) { case 250: setup |= DS1307_TRICKLE_CHARGER_250_OHM; @@ -508,6 +522,16 @@ static u8 do_trickle_setup_ds1339(struct ds1307 *ds1307, u32 ohms, bool diode) return setup; } +static u8 do_trickle_setup_rx8130(struct ds1307 *ds1307, u32 ohms, bool diode) +{ + /* make sure that the backup battery is enabled */ + u8 setup = RX8130_REG_CONTROL1_INIEN; + if (diode) + setup |= RX8130_REG_CONTROL1_CHGEN; + + return setup; +} + static irqreturn_t rx8130_irq(int irq, void *dev_id) { struct ds1307 *ds1307 = dev_id; @@ -896,6 +920,8 @@ static const struct chip_desc chips[last_ds_type] = { .bbsqi_bit = DS1339_BIT_BBSQI, .trickle_charger_reg = 0x10, .do_trickle_setup = &do_trickle_setup_ds1339, + .requires_trickle_resistor = true, + .charge_default = true, }, [ds_1340] = { .century_reg = DS1307_REG_HOUR, @@ -903,6 +929,8 @@ static const struct chip_desc chips[last_ds_type] = { .century_bit = DS1340_BIT_CENTURY, .do_trickle_setup = &do_trickle_setup_ds1339, .trickle_charger_reg = 0x08, + .requires_trickle_resistor = true, + .charge_default = true, }, [ds_1341] = { .century_reg = DS1307_REG_MONTH, @@ -926,6 +954,8 @@ static const struct chip_desc chips[last_ds_type] = { .offset = 0x10, .irq_handler = rx8130_irq, .rtc_ops = &rx8130_rtc_ops, + .trickle_charger_reg = RX8130_REG_CONTROL1, + .do_trickle_setup = &do_trickle_setup_rx8130, }, [m41t0] = { .rtc_ops = &m41txx_rtc_ops, @@ -1210,18 +1240,37 @@ static int ds1307_nvram_write(void *priv, unsigned int offset, void *val, static u8 ds1307_trickle_init(struct ds1307 *ds1307, const struct chip_desc *chip) { - u32 ohms; - bool diode = true; + u32 ohms, chargeable; + bool diode = chip->charge_default; if (!chip->do_trickle_setup) return 0; if (device_property_read_u32(ds1307->dev, "trickle-resistor-ohms", - &ohms)) + &ohms) && chip->requires_trickle_resistor) return 0; - if (device_property_read_bool(ds1307->dev, "trickle-diode-disable")) + /* aux-voltage-chargeable takes precedence over the deprecated + * trickle-diode-disable + */ + if (!device_property_read_u32(ds1307->dev, "aux-voltage-chargeable", + &chargeable)) { + switch (chargeable) { + case 0: + diode = false; + break; + case 1: + diode = true; + break; + default: + dev_warn(ds1307->dev, + "unsupported aux-voltage-chargeable value\n"); + break; + } + } else if (device_property_read_bool(ds1307->dev, + "trickle-diode-disable")) { diode = false; + } return chip->do_trickle_setup(ds1307, ohms, diode); } @@ -1627,7 +1676,6 @@ static int ds1307_probe(struct i2c_client *client, trickle_charger_setup = pdata->trickle_charger_setup; if (trickle_charger_setup && chip->trickle_charger_reg) { - trickle_charger_setup |= DS13XX_TRICKLE_CHARGER_MAGIC; dev_dbg(ds1307->dev, "writing trickle charger info 0x%x to 0x%x\n", trickle_charger_setup, chip->trickle_charger_reg); |