diff options
Diffstat (limited to 'drivers/rtc/rtc-isl12022.c')
| -rw-r--r-- | drivers/rtc/rtc-isl12022.c | 126 |
1 files changed, 120 insertions, 6 deletions
diff --git a/drivers/rtc/rtc-isl12022.c b/drivers/rtc/rtc-isl12022.c index a613257d1574..4eef7afcc8bc 100644 --- a/drivers/rtc/rtc-isl12022.c +++ b/drivers/rtc/rtc-isl12022.c @@ -9,6 +9,8 @@ */ #include <linux/bcd.h> +#include <linux/bitfield.h> +#include <linux/clk-provider.h> #include <linux/err.h> #include <linux/hwmon.h> #include <linux/i2c.h> @@ -31,6 +33,8 @@ #define ISL12022_REG_SR 0x07 #define ISL12022_REG_INT 0x08 +#define ISL12022_REG_PWR_VBAT 0x0a + #define ISL12022_REG_BETA 0x0d #define ISL12022_REG_TEMP_L 0x28 @@ -41,6 +45,12 @@ #define ISL12022_SR_LBAT75 (1 << 1) #define ISL12022_INT_WRTC (1 << 6) +#define ISL12022_INT_FO_MASK GENMASK(3, 0) +#define ISL12022_INT_FO_OFF 0x0 +#define ISL12022_INT_FO_32K 0x1 + +#define ISL12022_REG_VB85_MASK GENMASK(5, 3) +#define ISL12022_REG_VB75_MASK GENMASK(2, 0) #define ISL12022_BETA_TSE (1 << 7) @@ -141,12 +151,6 @@ static int isl12022_rtc_read_time(struct device *dev, struct rtc_time *tm) if (ret) return ret; - if (buf[ISL12022_REG_SR] & (ISL12022_SR_LBAT85 | ISL12022_SR_LBAT75)) { - dev_warn(dev, - "voltage dropped below %u%%, date and time is not reliable.\n", - buf[ISL12022_REG_SR] & ISL12022_SR_LBAT85 ? 85 : 75); - } - dev_dbg(dev, "raw data is sec=%02x, min=%02x, hr=%02x, mday=%02x, mon=%02x, year=%02x, wday=%02x, sr=%02x, int=%02x", buf[ISL12022_REG_SC], @@ -204,7 +208,34 @@ static int isl12022_rtc_set_time(struct device *dev, struct rtc_time *tm) return regmap_bulk_write(regmap, ISL12022_REG_SC, buf, sizeof(buf)); } +static int isl12022_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) +{ + struct regmap *regmap = dev_get_drvdata(dev); + u32 user, val; + int ret; + + switch (cmd) { + case RTC_VL_READ: + ret = regmap_read(regmap, ISL12022_REG_SR, &val); + if (ret) + return ret; + + user = 0; + if (val & ISL12022_SR_LBAT85) + user |= RTC_VL_BACKUP_LOW; + + if (val & ISL12022_SR_LBAT75) + user |= RTC_VL_BACKUP_EMPTY; + + return put_user(user, (u32 __user *)arg); + + default: + return -ENOIOCTLCMD; + } +} + static const struct rtc_class_ops isl12022_rtc_ops = { + .ioctl = isl12022_rtc_ioctl, .read_time = isl12022_rtc_read_time, .set_time = isl12022_rtc_set_time, }; @@ -215,10 +246,88 @@ static const struct regmap_config regmap_config = { .use_single_write = true, }; +static int isl12022_register_clock(struct device *dev) +{ + struct regmap *regmap = dev_get_drvdata(dev); + struct clk_hw *hw; + int ret; + + if (!device_property_present(dev, "#clock-cells")) { + /* + * Disabling the F_OUT pin reduces the power + * consumption in battery mode by ~25%. + */ + regmap_update_bits(regmap, ISL12022_REG_INT, ISL12022_INT_FO_MASK, + ISL12022_INT_FO_OFF); + + return 0; + } + + if (!IS_ENABLED(CONFIG_COMMON_CLK)) + return 0; + + /* + * For now, only support a fixed clock of 32768Hz (the reset default). + */ + ret = regmap_update_bits(regmap, ISL12022_REG_INT, + ISL12022_INT_FO_MASK, ISL12022_INT_FO_32K); + if (ret) + return ret; + + hw = devm_clk_hw_register_fixed_rate(dev, "isl12022", NULL, 0, 32768); + if (IS_ERR(hw)) + return PTR_ERR(hw); + + return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get, hw); +} + +static const u32 trip_levels[2][7] = { + { 2125000, 2295000, 2550000, 2805000, 3060000, 4250000, 4675000 }, + { 1875000, 2025000, 2250000, 2475000, 2700000, 3750000, 4125000 }, +}; + +static void isl12022_set_trip_levels(struct device *dev) +{ + struct regmap *regmap = dev_get_drvdata(dev); + u32 levels[2] = {0, 0}; + int ret, i, j, x[2]; + u8 val, mask; + + device_property_read_u32_array(dev, "isil,battery-trip-levels-microvolt", + levels, 2); + + for (i = 0; i < 2; i++) { + for (j = 0; j < ARRAY_SIZE(trip_levels[i]) - 1; j++) { + if (levels[i] <= trip_levels[i][j]) + break; + } + x[i] = j; + } + + val = FIELD_PREP(ISL12022_REG_VB85_MASK, x[0]) | + FIELD_PREP(ISL12022_REG_VB75_MASK, x[1]); + mask = ISL12022_REG_VB85_MASK | ISL12022_REG_VB75_MASK; + + ret = regmap_update_bits(regmap, ISL12022_REG_PWR_VBAT, mask, val); + if (ret) + dev_warn(dev, "unable to set battery alarm levels: %d\n", ret); + + /* + * Force a write of the TSE bit in the BETA register, in order + * to trigger an update of the LBAT75 and LBAT85 bits in the + * status register. In battery backup mode, those bits have + * another meaning, so without this, they may contain stale + * values for up to a minute after power-on. + */ + regmap_write_bits(regmap, ISL12022_REG_BETA, + ISL12022_BETA_TSE, ISL12022_BETA_TSE); +} + static int isl12022_probe(struct i2c_client *client) { struct rtc_device *rtc; struct regmap *regmap; + int ret; if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) return -ENODEV; @@ -231,6 +340,11 @@ static int isl12022_probe(struct i2c_client *client) dev_set_drvdata(&client->dev, regmap); + ret = isl12022_register_clock(&client->dev); + if (ret) + return ret; + + isl12022_set_trip_levels(&client->dev); isl12022_hwmon_register(&client->dev); rtc = devm_rtc_allocate_device(&client->dev); |