Re: [PATCH 8/8] power: bq27xxx_battery: Cleanup health checking

Pali Rohár
2015-07-23T16:22:24Z

On Wednesday 22 July 2015 16:52:00 Andrew F. Davis wrote:
> Reorganize the logic checking battery health and under temperature
> condition checking.
>
> Signed-off-by: Andrew F. Davis <afd@ti.com>
> ---
> drivers/power/bq27xxx_battery.c | 62 +++++++++++++++++++++++++++--------------
> 1 file changed, 41 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/power/bq27xxx_battery.c b/drivers/power/bq27xxx_battery.c
> index f148222..6775f65 100644
> --- a/drivers/power/bq27xxx_battery.c
> +++ b/drivers/power/bq27xxx_battery.c
> @@ -54,6 +54,8 @@
> #define BQ27XXX_FLAG_FC BIT(9)
> #define BQ27XXX_FLAG_OTD BIT(14)
> #define BQ27XXX_FLAG_OTC BIT(15)
> +#define BQ27XXX_FLAG_UT BIT(14)
> +#define BQ27XXX_FLAG_OT BIT(15)
>
> /* BQ27000 has different layout for Flags register */
> #define BQ27000_FLAG_EDVF BIT(0) /* Final End-of-Discharge-Voltage flag */
> @@ -624,10 +626,34 @@ static int bq27xxx_battery_read_pwr_avg(struct bq27xxx_device_info *di)
> */
> static int bq27xxx_battery_overtemp(struct bq27xxx_device_info *di, u16 flags)
> {
> - if (di->chip == BQ27500 || di->chip == BQ27541)
> + if (di->chip == BQ27500 || di->chip == BQ27541 || di->chip == BQ27545)
> return flags & (BQ27XXX_FLAG_OTC | BQ27XXX_FLAG_OTD);
> + if (di->chip == BQ27530 || di->chip == BQ27421)
> + return flags & BQ27XXX_FLAG_OT;
> +
> + return false;
> +}
> +
> +/*
> + * Returns true if a battery under temperature condition is detected
> + */
> +static int bq27xxx_battery_undertemp(struct bq27xxx_device_info *di, u16 flags)
> +{
> + if (di->chip == BQ27530 || di->chip == BQ27421)
> + return flags & BQ27XXX_FLAG_UT;
> +
> + return false;
> +}
> +
> +/*
> + * Returns true if a low state of charge condition is detected
> + */
> +static int bq27xxx_battery_dead(struct bq27xxx_device_info *di, u16 flags)
> +{
> + if (di->chip == BQ27000 || di->chip == BQ27010)
> + return flags & (BQ27000_FLAG_EDV1 | BQ27000_FLAG_EDVF);
> else
> - return flags & BQ27XXX_FLAG_OTC;
> + return flags & (BQ27XXX_FLAG_SOC1 | BQ27XXX_FLAG_SOCF);
> }
>
> /*
> @@ -636,29 +662,23 @@ static int bq27xxx_battery_overtemp(struct bq27xxx_device_info *di, u16 flags)
> */
> static int bq27xxx_battery_read_health(struct bq27xxx_device_info *di)
> {
> - u16 tval;
> + u16 flags;
>
> - tval = bq27xxx_read(di, BQ27XXX_REG_FLAGS, false);
> - if (tval < 0) {
> - dev_err(di->dev, "error reading flag register:%d\n", tval);
> - return tval;
> + flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, false);
> + if (flags < 0) {
> + dev_err(di->dev, "error reading flag register:%d\n", flags);
> + return flags;
> }
>
> - if (di->chip == BQ27000 || di->chip == BQ27010) {
> - if (tval & BQ27000_FLAG_EDV1)
> - tval = POWER_SUPPLY_HEALTH_DEAD;
> - else
> - tval = POWER_SUPPLY_HEALTH_GOOD;
> - } else {
> - if (tval & BQ27XXX_FLAG_SOCF)
> - tval = POWER_SUPPLY_HEALTH_DEAD;
> - else if (bq27xxx_battery_overtemp(di, tval))
> - tval = POWER_SUPPLY_HEALTH_OVERHEAT;
> - else
> - tval = POWER_SUPPLY_HEALTH_GOOD;
> - }
> + /* Unlikely but important to return first */
> + if (bq27xxx_battery_overtemp(di, flags))
> + return POWER_SUPPLY_HEALTH_OVERHEAT;
> + if (bq27xxx_battery_undertemp(di, flags))
> + return POWER_SUPPLY_HEALTH_COLD;
> + if (bq27xxx_battery_dead(di, flags))
> + return POWER_SUPPLY_HEALTH_DEAD;

Good candidates for "if (unlikely(...))" ?

>
> - return tval;
> + return POWER_SUPPLY_HEALTH_GOOD;
> }
>
> static void bq27xxx_battery_update(struct bq27xxx_device_info *di)

--
Pali Rohár
pali.rohar@gmail.com