power: 88pm88x_battery: save CC value before GPADC is enabled

when enable GPADC, the value of CC will be cleared,
so we should save it for later use.

Change-Id: I405ca4b3a709253ca8c4ba3bf046ab05a5df7588
Signed-off-by: Guosong Su <gssu@marvell.com>

3 files changed, 92 insertions, 36 deletions

diff --git a/drivers/mfd/88pm88x-core.c b/drivers/mfd/88pm88x-core.c
index 81c21edd6f2..ba757b4f14d 100644
--- a/drivers/mfd/88pm88x-core.c
+++ b/drivers/mfd/88pm88x-core.c
@@ -344,6 +344,51 @@ static void pm88x_verify_is_trimmed(struct pm88x_chip *chip)
 	}
 }
 
+/*
+ * fuel gauge initialization,
+ * stored CC for later use before GPADC enable.
+ */
+int pm88x_pre_fg_init(struct pm88x_chip *chip)
+{
+	int ret;
+	unsigned int val, mask;
+	u8 buf[5];
+
+	/*
+	 * set SD_PWRUP to enable sigma-delta
+	 * set CC_CLR_ON_RD to clear coulomb counter on read
+	 * set CC_EN to enable coulomb counter
+	 */
+	val = mask = PM88X_SD_PWRUP | PM88X_CC_CLR_ON_RD | PM88X_CC_EN;
+	ret = regmap_update_bits(chip->battery_regmap, PM88X_CC_CONFIG1,
+				 mask, val);
+	/* read columb counter to get the original SoC value */
+	regmap_read(chip->battery_regmap, PM88X_CC_CONFIG2, &val);
+	/*
+	 * set PM88X_CC_READ_REQ to read Qbat_cc,
+	 * if it has been set, then it means the data not ready
+	 */
+	if (!(val & PM88X_CC_READ_REQ))
+		regmap_update_bits(chip->battery_regmap, PM88X_CC_CONFIG2,
+				   PM88X_CC_READ_REQ, PM88X_CC_READ_REQ);
+	/* wait until Qbat_cc is ready */
+	do {
+		regmap_read(chip->battery_regmap, PM88X_CC_CONFIG2,
+			    &val);
+	} while ((val & PM88X_CC_READ_REQ));
+
+	ret = regmap_bulk_read(chip->battery_regmap, PM88X_CC_VAL1,
+			       buf, 5);
+	if (ret < 0)
+		return ret;
+	chip->pre_ccnt_uc = (s64) (((s64)(buf[4]) << 32)
+			 | (u64)(buf[3] << 24) | (u64)(buf[2] << 16)
+			 | (u64)(buf[1] << 8) | (u64)buf[0]);
+	dev_info(chip->dev, "buf[0 ~ 4] = 0x%x, 0x%x, 0x%x, 0x%x, 0x%x\n",
+		 buf[0], buf[1], buf[2], buf[3], buf[4]);
+	return 0;
+}
+
 int pm88x_post_init_chip(struct pm88x_chip *chip)
 {
 	int ret;
@@ -375,6 +420,11 @@ int pm88x_post_init_chip(struct pm88x_chip *chip)
 	}
 	chip->rtc_wakeup = !!(val & PM88X_ALARM_WAKEUP);
 
+	ret = pm88x_pre_fg_init(chip);
+	if (ret < 0) {
+		dev_err(chip->dev, "Failed to initial fuel gauge: %d\n", ret);
+		return ret;
+	}
 	parse_powerup_down_log(chip);
 
 	return 0;
diff --git a/drivers/power/88pm88x_battery.c b/drivers/power/88pm88x_battery.c
index 42f6a6a8ce5..464a47f9e54 100644
--- a/drivers/power/88pm88x_battery.c
+++ b/drivers/power/88pm88x_battery.c
@@ -41,21 +41,6 @@
 
 #define PM88X_VBAT_LOW_TH		(0x18)
 
-#define PM88X_CC_CONFIG1		(0x01)
-#define PM88X_CC_EN			(1 << 0)
-#define PM88X_CC_CLR_ON_RD		(1 << 2)
-#define PM88X_SD_PWRUP			(1 << 3)
-
-#define PM88X_CC_CONFIG2		(0x02)
-#define PM88X_CC_READ_REQ		(1 << 0)
-#define PM88X_OFFCOMP_EN		(1 << 1)
-
-#define PM88X_CC_VAL1			(0x03)
-#define PM88X_CC_VAL2			(0x04)
-#define PM88X_CC_VAL3			(0x05)
-#define PM88X_CC_VAL4			(0x06)
-#define PM88X_CC_VAL5			(0x07)
-
 #define PM88X_IBAT_VAL1			(0x08)		/* LSB */
 #define PM88X_IBAT_VAL2			(0x09)
 #define PM88X_IBAT_VAL3			(0x0a)
@@ -1545,62 +1530,52 @@ static int pm88x_setup_fuelgauge(struct pm88x_battery_info *info)
 		return true;
 	}
 
-	/* 0. set the CCNT_LOW_TH before the CC_EN is set 23.43mC/LSB */
+	/* set the CCNT_LOW_TH before the CC_EN is set 23.43mC/LSB */
 	tmp = ccnt_data.alart_cc * 100 / 2343;
 	buf[0] = (u8)(tmp & 0xff);
 	buf[1] = (u8)((tmp & 0xff00) >> 8);
 	regmap_bulk_write(info->chip->battery_regmap, PM88X_CC_LOW_TH1, buf, 2);
 
-	/* 1. set the EOC battery current as 100mA, done in charger driver */
-
-	/* 2. use battery current to decide the EOC */
+	/* use battery current to decide the EOC */
 	data = mask = PM88X_IBAT_MEAS_EN;
 	ret = regmap_update_bits(info->chip->battery_regmap,
 				PM88X_IBAT_EOC_CONFIG, mask, data);
-	/*
-	 * 3. set SD_PWRUP to enable sigma-delta
-	 *    set CC_CLR_ON_RD to clear coulomb counter on read
-	 *    set CC_EN to enable coulomb counter
-	 */
-	data = mask = PM88X_SD_PWRUP | PM88X_CC_CLR_ON_RD | PM88X_CC_EN;
-	ret = regmap_update_bits(info->chip->battery_regmap, PM88X_CC_CONFIG1,
-				 mask, data);
-	if (ret < 0)
-		goto out;
+
+	/* enable CC by default */
 	pm88x_cc_enable_bootup(info);
 
-	/* 5. enable VBAT measurement */
+	/* enable VBAT measurement */
 	data = mask = PM88X_VBAT_MEAS_EN;
 	ret = regmap_update_bits(info->chip->gpadc_regmap, PM88X_GPADC_CONFIG1,
 				 mask, data);
 	if (ret < 0)
 		goto out;
 
-	/* 6. hold the sleep counter until this bit is released or be reset */
+	/* hold the sleep counter until this bit is released or be reset */
 	data = mask = PM88X_SLP_CNT_HOLD;
 	ret = regmap_update_bits(info->chip->base_regmap,
 				 PM88X_SLP_CNT2, mask, data);
 	if (ret < 0)
 		goto out;
 
-	/* 7. set the VBAT threashold as 3000mV: 0x890 * 1.367mV/LSB = 2.996V */
+	/* set the VBAT threashold as 3000mV: 0x890 * 1.367mV/LSB = 2.996V */
 	ret = regmap_write(info->chip->gpadc_regmap, PM88X_VBAT_LOW_TH, 0x89);
 	if (ret < 0)
 		goto out;
 
-	/* 8. disable battery detection by HW */
+	/* disable battery detection by HW */
 	ret = regmap_update_bits(info->chip->gpadc_regmap, PM88X_GPADC_CONFIG8,
 				 PM88X_GPADC_BD_EN, 0);
 	if (ret < 0)
 		goto out;
 
-	/* 9. disable battery temperature monitoring */
+	/* disable battery temperature monitoring */
 	ret = regmap_update_bits(info->chip->battery_regmap, PM88X_CHG_CONFIG1,
 				 PM88X_BATTEMP_MON_EN, 0);
 	if (ret < 0)
 		goto out;
 
-	/* 10. disable battery temperature monitoring2 for 88pm886-A1 and 88pm880-xx */
+	/* disable battery temperature monitoring2 for 88pm886-A1 and 88pm880-xx */
 	switch (info->chip->type) {
 	case PM886:
 		if (info->chip->chip_id == PM886_A1)
@@ -1622,6 +1597,36 @@ out:
 	return ret;
 }
 
+/* add stored CC to soc from saved. */
+static int pm88x_battery_init_calc_ccnt(struct pm88x_battery_info *info,
+				   struct ccnt *ccnt_val, int soc_from_save)
+{
+	int factor, last_cc, soc_to_save;
+	s64 ccnt_uc = 0, ccnt_mc = 0;
+
+	/* get the original SoC value */
+	ccnt_uc = info->chip->pre_ccnt_uc;
+	/* Factor is nC */
+	factor = (info->cc_fixup) * 715 / 100;
+	ccnt_uc = ccnt_uc * factor;
+	ccnt_uc = div_s64(ccnt_uc, 1000);
+	ccnt_mc = div_s64(ccnt_uc, 1000);
+	last_cc = (ccnt_val->max_cc / (1000 * PM88X_CAP_FAC100)) * soc_from_save;
+
+	/* add the value */
+	last_cc += ccnt_mc;
+	/* clap battery SoC for sanity check */
+	if (last_cc > ccnt_val->max_cc)
+		soc_to_save = 1000 * PM88X_CAP_FAC100;
+	if (last_cc < 0)
+		soc_to_save = 0;
+
+	soc_to_save = last_cc * 100 / (ccnt_val->max_cc / (10 * PM88X_CAP_FAC100));
+	dev_info(info->dev, "%s<-- ccnt_val->soc: %d%%, new->last_cc: %d mC\n",
+		 __func__, soc_to_save, last_cc);
+	return soc_to_save;
+}
+
 static void pm88x_init_soc_cycles(struct pm88x_battery_info *info,
 				 struct ccnt *ccnt_val,
 				 int *initial_soc, int *initial_cycles)
@@ -1669,6 +1674,7 @@ static void pm88x_init_soc_cycles(struct pm88x_battery_info *info,
 	dev_info(info->dev,
 		 "---> %s: soc_from_saved = %d, reliable_from_saved = %d\n",
 		 __func__, soc_from_saved, reliable_from_saved);
+	soc_from_saved = pm88x_battery_init_calc_ccnt(info, ccnt_val, soc_from_saved);
 
 	/* ---------------------------------------------------------------- */
 	/*
@@ -1811,7 +1817,6 @@ static void pm88x_init_soc_cycles(struct pm88x_battery_info *info,
 end:
 	/* update ccnt_data timely */
 	init_ccnt_data(ccnt_val, *initial_soc);
-	pm88x_battery_calc_ccnt(info, &ccnt_data);
 	dev_info(info->dev,
 		 "<---- %s: initial soc = %d\n", __func__, *initial_soc);
 
diff --git a/include/linux/mfd/88pm88x.h b/include/linux/mfd/88pm88x.h
index f17a8632a7b..b6e64a79f83 100644
--- a/include/linux/mfd/88pm88x.h
+++ b/include/linux/mfd/88pm88x.h
@@ -190,6 +190,7 @@ struct pm88x_chip {
 	u8 powerdown1;
 	u8 powerdown2;
 	u8 powerup;
+	s64 pre_ccnt_uc;
 	bool trimming_status;
 
 	struct notifier_block reboot_notifier;