commit f17df2402b795faf2c03de6d8a5b12378674f3be
author choongryeol.lee <choongryeol.lee@lge.com> Wed Oct 24 02:13:41 2012 -0700
committer Iliyan Malchev <malchev@google.com> Fri Oct 26 16:44:36 2012 -0700
tree 747d6e8d2bec4f45b80abeb2a1c4efbc54605611
parent f063d16ebf6c1e5deff02e59b404fd5c8fade375

power: pm8921-bms: use pmic power reason to check restart

For accurate SoC calculation, bms need to know if target
was booted from reset or power down. Previously, minimum
CC value check was used to detect power on reason.
But this minimum CC value check is useless when charger is
connected. So, this patch use pmic power on reason to know
the exact power on reason.

Signed-off-by: Iliyan Malchev <malchev@google.com>

drivers/power/pm8921-bms.c

diff --git a/drivers/power/pm8921-bms.c b/drivers/power/pm8921-bms.c
index 0b43c94..ea95ec1 100644
--- a/drivers/power/pm8921-bms.c
+++ b/drivers/power/pm8921-bms.c
@@ -55,7 +55,8 @@
 #define TEMP_IAVG_STORAGE	0x105
 #define TEMP_IAVG_STORAGE_USE_MASK	0x0F
 
-#define CC_RAW_5MAH	0x00110000
+#define PON_CNTRL_6		0x018
+#define WD_BIT		BIT(7)
 
 enum pmic_bms_interrupts {
 	PM8921_BMS_SBI_WRITE_OK,
@@ -158,6 +159,7 @@
 	int			wlc_max_voltage_uv;
 	int			(*wlc_is_plugged)(void);
 	int			vbat_at_cv;
+	int			(*is_warm_reset)(void);
 };
 
 /*
@@ -1007,6 +1009,20 @@
 	return compensated_ocv;
 }
 
+static bool is_warm_restart(struct pm8921_bms_chip *chip)
+{
+	u8 reg;
+	int rc;
+
+	rc = pm8xxx_readb(chip->dev->parent, PON_CNTRL_6, &reg);
+	if (rc) {
+		pr_err("err reading pon 6 rc = %d\n", rc);
+		return false;
+	}
+
+	return reg & WD_BIT;
+}
+
 static int read_soc_params_raw(struct pm8921_bms_chip *chip,
 				struct pm8921_soc_params *raw)
 {
@@ -1033,10 +1049,9 @@
 						raw->last_good_ocv_uv);
 		chip->last_ocv_uv = raw->last_good_ocv_uv;
 
-		if (raw->cc > CC_RAW_5MAH) {
+		if (is_warm_restart(chip)) {
 			shutdown_soc_invalid = 1;
-			pr_info("cc_raw = 0x%x greater than 5mAh 0x%x\n",
-				       raw->cc, CC_RAW_5MAH);
+			pr_info("discard shutdown soc! cc_raw = 0x%x\n", raw->cc);
 		}
 
 		pr_debug("PON_OCV_UV = %d\n", chip->last_ocv_uv);