diff options
-rw-r--r-- | drivers/mfd/rk808.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/drivers/mfd/rk808.c b/drivers/mfd/rk808.c index 0324422b3b10..bd0215069875 100644 --- a/drivers/mfd/rk808.c +++ b/drivers/mfd/rk808.c @@ -29,10 +29,40 @@ struct rk808_reg_data { int value; }; +static bool rk808_is_volatile_reg(struct device *dev, unsigned int reg) +{ + /* + * Notes: + * - Technically the ROUND_30s bit makes RTC_CTRL_REG volatile, but + * we don't use that feature. It's better to cache. + * - It's unlikely we care that RK808_DEVCTRL_REG is volatile since + * bits are cleared in case when we shutoff anyway, but better safe. + */ + + switch (reg) { + case RK808_SECONDS_REG ... RK808_WEEKS_REG: + case RK808_RTC_STATUS_REG: + case RK808_VB_MON_REG: + case RK808_THERMAL_REG: + case RK808_DCDC_UV_STS_REG: + case RK808_LDO_UV_STS_REG: + case RK808_DCDC_PG_REG: + case RK808_LDO_PG_REG: + case RK808_DEVCTRL_REG: + case RK808_INT_STS_REG1: + case RK808_INT_STS_REG2: + return true; + } + + return false; +} + static const struct regmap_config rk808_regmap_config = { .reg_bits = 8, .val_bits = 8, .max_register = RK808_IO_POL_REG, + .cache_type = REGCACHE_RBTREE, + .volatile_reg = rk808_is_volatile_reg, }; static struct resource rtc_resources[] = { |