Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit f1771332 authored by David Keitel's avatar David Keitel
Browse files

power: qpnp-fg: report battery resistance 



Add support to report the battery resistance which
is a half float point encoded value as the following
power supply property:

  * POWER_SUPPLY_PROP_RESISTANCE

Change-Id: I6630c276579d7166a64c665cdfde99fc1d0d247e
Signed-off-by: default avatarDavid Keitel <dkeitel@codeaurora.org>
parent 93090ab4

drivers/power/qpnp-fg.c

+47 −0
Original line number Diff line number Diff line
@@ -115,6 +115,7 @@ enum fg_mem_data_index { 
	FG_DATA_OCV,

	FG_DATA_VOLTAGE,

	FG_DATA_CURRENT,

	FG_DATA_BATT_ESR,

	FG_DATA_MAX,

};
@@ -147,6 +148,7 @@ static struct fg_mem_data fg_data[FG_DATA_MAX] = { 
	DATA(OCV,             0x588,   3,      2,     -EINVAL),

	DATA(VOLTAGE,         0x5CC,   1,      2,     -EINVAL),

	DATA(CURRENT,         0x5CC,   3,      2,     -EINVAL),

	DATA(BATT_ESR,        0x554,   2,      2,     -EINVAL),

};



static int fg_debug_mask;
@@ -744,6 +746,45 @@ static int set_prop_jeita_temp(struct fg_chip *chip, 
	return rc;

}



#define EXPONENT_MASK		0xF800

#define MANTISSA_MASK		0x3FF

#define SIGN			BIT(10)

#define EXPONENT_SHIFT		11

#define MICRO_UNIT		1000000ULL

static int64_t float_decode(u16 reg)

{

	int64_t final_val, exponent_val, mantissa_val;

	int exponent, mantissa, n;

	bool sign;



	exponent = (reg & EXPONENT_MASK) >> EXPONENT_SHIFT;

	mantissa = (reg & MANTISSA_MASK);

	sign = !!(reg & SIGN);



	pr_debug("exponent=%d mantissa=%d sign=%d\n", exponent, mantissa, sign);



	mantissa_val = mantissa * MICRO_UNIT;



	n = exponent - 15;

	if (n < 0)

		exponent_val = MICRO_UNIT >> -n;

	else

		exponent_val = MICRO_UNIT << n;



	n = n - 10;

	if (n < 0)

		mantissa_val >>= -n;

	else

		mantissa_val <<= n;



	final_val = exponent_val + mantissa_val;



	if (sign)

		final_val *= -1;



	return final_val;

}



#define LSB_16B		153

#define TEMP_LSB_16B	625

#define DECIKELVIN	2730
@@ -780,6 +821,8 @@ static void update_sram_data(struct work_struct *work) 
		case FG_DATA_CURRENT:

			fg_data[i].value = temp * LSB_16B;

			break;

		case FG_DATA_BATT_ESR:

			fg_data[i].value = float_decode((u16) temp);

		};



		if (fg_debug_mask & FG_MEM_DEBUG_READS)
@@ -816,6 +859,7 @@ static enum power_supply_property fg_power_props[] = { 
	POWER_SUPPLY_PROP_TEMP,

	POWER_SUPPLY_PROP_COOL_TEMP,

	POWER_SUPPLY_PROP_WARM_TEMP,

	POWER_SUPPLY_PROP_RESISTANCE,

};



static int fg_power_get_property(struct power_supply *psy,
@@ -846,6 +890,9 @@ static int fg_power_get_property(struct power_supply *psy, 
	case POWER_SUPPLY_PROP_WARM_TEMP:

		val->intval = get_prop_jeita_temp(chip, FG_MEM_SOFT_HOT);

		break;

	case POWER_SUPPLY_PROP_RESISTANCE:

		val->intval = get_sram_prop_now(chip, FG_DATA_BATT_ESR);

		break;

	default:

		return -EINVAL;

	}