power: pm8921-bms: scale rbatt with temperature and soc
The rbatt was observed to change with battery temperature and the state
of charge of the battery. Update the BMS driver and the battery data
to include and use a rbatt table indicating its changes w.r.t temperature
and state of charge.
On similar lines provide api for other systems to query battery resistance.
Change-Id: I681675db537b70919e6e0437bd400ce53bf97096
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
diff --git a/drivers/power/pm8921-bms.c b/drivers/power/pm8921-bms.c
index 1778d62..71d604d 100644
--- a/drivers/power/pm8921-bms.c
+++ b/drivers/power/pm8921-bms.c
@@ -90,7 +90,8 @@
struct single_row_lut *fcc_temp_lut;
struct single_row_lut *fcc_sf_lut;
struct pc_temp_ocv_lut *pc_temp_ocv_lut;
- struct pc_sf_lut *pc_sf_lut;
+ struct sf_lut *pc_sf_lut;
+ struct sf_lut *rbatt_sf_lut;
struct work_struct calib_hkadc_work;
struct delayed_work calib_ccadc_work;
unsigned int calib_delay_ms;
@@ -118,6 +119,8 @@
int max_voltage_uv;
int batt_temp_suspend;
+ int soc_rbatt_suspend;
+ int default_rbatt_mohm;
};
static struct pm8921_bms_chip *the_chip;
@@ -620,8 +623,9 @@
return 100;
}
-static int interpolate_scalingfactor_pc(struct pm8921_bms_chip *chip,
- int cycles, int pc)
+static int interpolate_scalingfactor(struct pm8921_bms_chip *chip,
+ struct sf_lut *sf_lut,
+ int row_entry, int pc)
{
int i, scalefactorrow1, scalefactorrow2, scalefactor;
int rows, cols;
@@ -632,71 +636,71 @@
* sf table could be null when no battery aging data is available, in
* that case return 100%
*/
- if (!chip->pc_sf_lut)
+ if (!sf_lut)
return 100;
- rows = chip->pc_sf_lut->rows;
- cols = chip->pc_sf_lut->cols;
- if (pc > chip->pc_sf_lut->percent[0]) {
+ rows = sf_lut->rows;
+ cols = sf_lut->cols;
+ if (pc > sf_lut->percent[0]) {
pr_debug("pc %d greater than known pc ranges for sfd\n", pc);
row1 = 0;
row2 = 0;
}
- if (pc < chip->pc_sf_lut->percent[rows - 1]) {
+ if (pc < sf_lut->percent[rows - 1]) {
pr_debug("pc %d less than known pc ranges for sf", pc);
row1 = rows - 1;
row2 = rows - 1;
}
for (i = 0; i < rows; i++) {
- if (pc == chip->pc_sf_lut->percent[i]) {
+ if (pc == sf_lut->percent[i]) {
row1 = i;
row2 = i;
break;
}
- if (pc > chip->pc_sf_lut->percent[i]) {
+ if (pc > sf_lut->percent[i]) {
row1 = i - 1;
row2 = i;
break;
}
}
- if (cycles < chip->pc_sf_lut->cycles[0])
- cycles = chip->pc_sf_lut->cycles[0];
- if (cycles > chip->pc_sf_lut->cycles[cols - 1])
- cycles = chip->pc_sf_lut->cycles[cols - 1];
+ if (row_entry < sf_lut->row_entries[0])
+ row_entry = sf_lut->row_entries[0];
+ if (row_entry > sf_lut->row_entries[cols - 1])
+ row_entry = sf_lut->row_entries[cols - 1];
for (i = 0; i < cols; i++)
- if (cycles <= chip->pc_sf_lut->cycles[i])
+ if (row_entry <= sf_lut->row_entries[i])
break;
- if (cycles == chip->pc_sf_lut->cycles[i]) {
+ if (row_entry == sf_lut->row_entries[i]) {
scalefactor = linear_interpolate(
- chip->pc_sf_lut->sf[row1][i],
- chip->pc_sf_lut->percent[row1],
- chip->pc_sf_lut->sf[row2][i],
- chip->pc_sf_lut->percent[row2],
+ sf_lut->sf[row1][i],
+ sf_lut->percent[row1],
+ sf_lut->sf[row2][i],
+ sf_lut->percent[row2],
pc);
return scalefactor;
}
scalefactorrow1 = linear_interpolate(
- chip->pc_sf_lut->sf[row1][i - 1],
- chip->pc_sf_lut->cycles[i - 1],
- chip->pc_sf_lut->sf[row1][i],
- chip->pc_sf_lut->cycles[i],
- cycles);
+ sf_lut->sf[row1][i - 1],
+ sf_lut->row_entries[i - 1],
+ sf_lut->sf[row1][i],
+ sf_lut->row_entries[i],
+ row_entry);
scalefactorrow2 = linear_interpolate(
- chip->pc_sf_lut->sf[row2][i - 1],
- chip->pc_sf_lut->cycles[i - 1],
- chip->pc_sf_lut->sf[row2][i],
- chip->pc_sf_lut->cycles[i],
- cycles);
+ sf_lut->sf[row2][i - 1],
+ sf_lut->row_entries[i - 1],
+ sf_lut->sf[row2][i],
+ sf_lut->row_entries[i],
+ row_entry);
scalefactor = linear_interpolate(
scalefactorrow1,
- chip->pc_sf_lut->percent[row1],
+ sf_lut->percent[row1],
scalefactorrow2,
- chip->pc_sf_lut->percent[row2],
+ sf_lut->percent[row2],
pc);
return scalefactor;
@@ -927,6 +931,27 @@
return 0;
}
+static int get_rbatt(struct pm8921_bms_chip *chip, int soc_rbatt, int batt_temp)
+{
+ int rbatt, scalefactor;
+
+ rbatt = (last_rbatt < 0) ? chip->default_rbatt_mohm : last_rbatt;
+ pr_debug("rbatt before scaling = %d\n", rbatt);
+ if (chip->rbatt_sf_lut == NULL) {
+ pr_debug("RBATT = %d\n", rbatt);
+ return rbatt;
+ }
+
+ scalefactor = interpolate_scalingfactor(chip, chip->rbatt_sf_lut,
+ batt_temp, soc_rbatt);
+ pr_debug("rbatt sf = %d for batt_temp = %d, soc_rbatt = %d\n",
+ scalefactor, batt_temp, soc_rbatt);
+ rbatt = (rbatt * scalefactor) / 100;
+
+ pr_debug("RBATT = %d\n", rbatt);
+ return rbatt;
+}
+
static int calculate_rbatt_resume(struct pm8921_bms_chip *chip,
struct pm8921_rbatt_params *raw)
{
@@ -1000,7 +1025,7 @@
return rc;
}
- rbatt = (last_rbatt < 0) ? DEFAULT_RBATT_MOHMS : last_rbatt;
+ rbatt = (last_rbatt < 0) ? chip->default_rbatt_mohm : last_rbatt;
*ocv = vbatt + (ibatt_ua * rbatt)/1000;
return 0;
}
@@ -1014,7 +1039,8 @@
pr_debug("pc = %u for ocv = %dmicroVolts batt_temp = %d\n",
pc, ocv_uv, batt_temp);
- scalefactor = interpolate_scalingfactor_pc(chip, chargecycles, pc);
+ scalefactor = interpolate_scalingfactor(chip,
+ chip->pc_sf_lut, chargecycles, pc);
pr_debug("scalefactor = %u batt_temp = %d\n", scalefactor, batt_temp);
/* Multiply the initial FCC value by the scale factor. */
@@ -1051,12 +1077,10 @@
}
static int calculate_unusable_charge_uah(struct pm8921_bms_chip *chip,
- struct pm8921_soc_params *raw,
- int fcc_uah, int batt_temp, int chargecycles)
+ int rbatt, int fcc_uah,
+ int batt_temp, int chargecycles)
{
- int rbatt, voltage_unusable_uv, pc_unusable;
-
- rbatt = (last_rbatt < 0) ? DEFAULT_RBATT_MOHMS : last_rbatt;
+ int voltage_unusable_uv, pc_unusable;
/* calculate unusable charge */
voltage_unusable_uv = (rbatt * chip->i_test)
@@ -1106,18 +1130,16 @@
int *fcc_uah,
int *unusable_charge_uah,
int *remaining_charge_uah,
- int *cc_uah)
+ int *cc_uah,
+ int *rbatt)
{
unsigned long flags;
+ int soc_rbatt;
*fcc_uah = calculate_fcc_uah(chip, batt_temp, chargecycles);
pr_debug("FCC = %uuAh batt_temp = %d, cycles = %d\n",
*fcc_uah, batt_temp, chargecycles);
- *unusable_charge_uah = calculate_unusable_charge_uah(chip, raw,
- *fcc_uah, batt_temp, chargecycles);
-
- pr_debug("UUC = %uuAh\n", *unusable_charge_uah);
spin_lock_irqsave(&chip->bms_100_lock, flags);
/* calculate remainging charge */
@@ -1132,6 +1154,15 @@
(int64_t)raw->cc - chip->cc_reading_at_100,
chip->cc_reading_at_100);
spin_unlock_irqrestore(&chip->bms_100_lock, flags);
+
+ soc_rbatt = ((*remaining_charge_uah - *cc_uah) * 100) / *fcc_uah;
+ if (soc_rbatt < 0)
+ soc_rbatt = 0;
+ *rbatt = get_rbatt(chip, soc_rbatt, batt_temp);
+
+ *unusable_charge_uah = calculate_unusable_charge_uah(chip, *rbatt,
+ *fcc_uah, batt_temp, chargecycles);
+ pr_debug("UUC = %uuAh\n", *unusable_charge_uah);
}
static int calculate_real_fcc_uah(struct pm8921_bms_chip *chip,
@@ -1143,12 +1174,14 @@
int remaining_charge_uah;
int cc_uah;
int real_fcc_uah;
+ int rbatt;
calculate_soc_params(chip, raw, batt_temp, chargecycles,
&fcc_uah,
&unusable_charge_uah,
&remaining_charge_uah,
- &cc_uah);
+ &cc_uah,
+ &rbatt);
real_fcc_uah = remaining_charge_uah - cc_uah;
*ret_fcc_uah = fcc_uah;
@@ -1170,12 +1203,14 @@
int remaining_charge_uah, soc;
int update_userspace = 1;
int cc_uah;
+ int rbatt;
calculate_soc_params(chip, raw, batt_temp, chargecycles,
&fcc_uah,
&unusable_charge_uah,
&remaining_charge_uah,
- &cc_uah);
+ &cc_uah,
+ &rbatt);
/* calculate remaining usable charge */
remaining_usable_charge_uah = remaining_charge_uah
@@ -1384,6 +1419,44 @@
}
EXPORT_SYMBOL_GPL(pm8921_bms_get_percent_charge);
+int pm8921_bms_get_rbatt(void)
+{
+ int batt_temp, rc;
+ struct pm8xxx_adc_chan_result result;
+ struct pm8921_soc_params raw;
+ int fcc_uah;
+ int unusable_charge_uah;
+ int remaining_charge_uah;
+ int cc_uah;
+ int rbatt;
+
+ if (!the_chip) {
+ pr_err("called before initialization\n");
+ return -EINVAL;
+ }
+
+ rc = pm8xxx_adc_read(the_chip->batt_temp_channel, &result);
+ if (rc) {
+ pr_err("error reading adc channel = %d, rc = %d\n",
+ the_chip->batt_temp_channel, rc);
+ return rc;
+ }
+ pr_debug("batt_temp phy = %lld meas = 0x%llx\n", result.physical,
+ result.measurement);
+ batt_temp = (int)result.physical;
+
+ read_soc_params_raw(the_chip, &raw);
+
+ calculate_soc_params(the_chip, &raw, batt_temp, last_chargecycles,
+ &fcc_uah,
+ &unusable_charge_uah,
+ &remaining_charge_uah,
+ &cc_uah,
+ &rbatt);
+ return rbatt;
+}
+EXPORT_SYMBOL_GPL(pm8921_bms_get_rbatt);
+
int pm8921_bms_get_fcc(void)
{
int batt_temp, rc;
@@ -1652,6 +1725,10 @@
int rc;
struct pm8xxx_adc_chan_result result;
struct pm8921_bms_chip *chip = dev_get_drvdata(dev);
+ struct pm8921_soc_params raw;
+ int fcc_uah;
+ int remaining_charge_uah;
+ int cc_uah;
chip->batt_temp_suspend = 0;
rc = pm8xxx_adc_read(chip->batt_temp_channel, &result);
@@ -1660,20 +1737,66 @@
chip->batt_temp_channel, rc);
}
chip->batt_temp_suspend = (int)result.physical;
+ read_soc_params_raw(chip, &raw);
+
+ fcc_uah = calculate_fcc_uah(chip,
+ chip->batt_temp_suspend, last_chargecycles);
+ pr_debug("FCC = %uuAh batt_temp = %d, cycles = %d\n",
+ fcc_uah, chip->batt_temp_suspend, last_chargecycles);
+ /* calculate remainging charge */
+ remaining_charge_uah = calculate_remaining_charge_uah(chip, &raw,
+ fcc_uah, chip->batt_temp_suspend,
+ last_chargecycles);
+ pr_debug("RC = %uuAh\n", remaining_charge_uah);
+
+ /* calculate cc micro_volt_hour */
+ calculate_cc_uah(chip, raw.cc, &cc_uah);
+ pr_debug("cc_uah = %duAh raw->cc = %x cc = %lld after subtracting %d\n",
+ cc_uah, raw.cc,
+ (int64_t)raw.cc - chip->cc_reading_at_100,
+ chip->cc_reading_at_100);
+ chip->soc_rbatt_suspend = ((remaining_charge_uah - cc_uah) * 100)
+ / fcc_uah;
return 0;
}
+#define DELTA_RBATT_PERCENT 10
static int pm8921_bms_resume(struct device *dev)
{
struct pm8921_rbatt_params raw;
struct pm8921_bms_chip *chip = dev_get_drvdata(dev);
int rbatt;
+ int expected_rbatt;
+ int scalefactor;
+ int delta_rbatt;
read_rbatt_params_raw(chip, &raw);
rbatt = calculate_rbatt_resume(chip, &raw);
- if (rbatt > 0) /* TODO Check for rbatt values bound based on cycles */
+
+ if (rbatt < 0)
+ return 0;
+
+ expected_rbatt
+ = (last_rbatt < 0) ? chip->default_rbatt_mohm : last_rbatt;
+
+ if (chip->rbatt_sf_lut) {
+ scalefactor = interpolate_scalingfactor(chip,
+ chip->rbatt_sf_lut,
+ chip->batt_temp_suspend,
+ chip->soc_rbatt_suspend);
+ rbatt = rbatt * 100 / scalefactor;
+ }
+
+ delta_rbatt = expected_rbatt - rbatt;
+ if (delta_rbatt)
+ delta_rbatt = -delta_rbatt;
+ /*
+ * only update last_rbatt if rbatt is within some
+ * percent of expected_rbatt
+ */
+ if (delta_rbatt * 100 <= DELTA_RBATT_PERCENT * expected_rbatt)
last_rbatt = rbatt;
- chip->batt_temp_suspend = -EINVAL;
+
return 0;
}
@@ -1767,7 +1890,9 @@
battery_id)) {
goto desay;
} else {
- goto unknown;
+ pr_warn("invalid battid, palladium 1500 assumed batt_id %llx\n",
+ battery_id);
+ goto palladium;
}
palladium:
@@ -1776,22 +1901,17 @@
chip->fcc_sf_lut = palladium_1500_data.fcc_sf_lut;
chip->pc_temp_ocv_lut = palladium_1500_data.pc_temp_ocv_lut;
chip->pc_sf_lut = palladium_1500_data.pc_sf_lut;
+ chip->rbatt_sf_lut = palladium_1500_data.rbatt_sf_lut;
+ chip->default_rbatt_mohm
+ = palladium_1500_data.default_rbatt_mohm;
return 0;
desay:
chip->fcc = desay_5200_data.fcc;
chip->fcc_temp_lut = desay_5200_data.fcc_temp_lut;
- chip->fcc_sf_lut = desay_5200_data.fcc_sf_lut;
chip->pc_temp_ocv_lut = desay_5200_data.pc_temp_ocv_lut;
chip->pc_sf_lut = desay_5200_data.pc_sf_lut;
- return 0;
-unknown:
- pr_warn("invalid battery id, palladium 1500 assumed batt_id %llx\n",
- battery_id);
- chip->fcc = palladium_1500_data.fcc;
- chip->fcc_temp_lut = palladium_1500_data.fcc_temp_lut;
- chip->fcc_sf_lut = palladium_1500_data.fcc_sf_lut;
- chip->pc_temp_ocv_lut = palladium_1500_data.pc_temp_ocv_lut;
- chip->pc_sf_lut = palladium_1500_data.pc_sf_lut;
+ chip->rbatt_sf_lut = desay_5200_data.rbatt_sf_lut;
+ chip->default_rbatt_mohm = desay_5200_data.default_rbatt_mohm;
return 0;
}
@@ -2087,6 +2207,16 @@
goto free_chip;
}
+ if (chip->pc_temp_ocv_lut == NULL) {
+ pr_err("temp ocv lut table is NULL\n");
+ rc = -EINVAL;
+ goto free_chip;
+ }
+
+ /* set defaults in the battery data */
+ if (chip->default_rbatt_mohm <= 0)
+ chip->default_rbatt_mohm = DEFAULT_RBATT_MOHMS;
+
chip->batt_temp_channel = pdata->bms_cdata.batt_temp_channel;
chip->vbat_channel = pdata->bms_cdata.vbat_channel;
chip->ref625mv_channel = pdata->bms_cdata.ref625mv_channel;