int ltc294x_get_current( int *val) {
struct ltc294x_info *info = <c2943_info;
int ret;
u8 datar[2];
s32 value;
// reset will have manual trigger control flag sent
// ltc294x_reset(2);
// for(i=0;i<5;i++)
// {
// nrf_delay_ms(40);
// ret = ltc294x_read_regs(info->client,
// LTC294X_REG_CONTROL, &datar[0], 1);
// if((datar[0]<C2943_REG_CONTROL_MODE_MASK)==0)
// break;
// }
// if (i>=5) return -1;
ret = ltc294x_read_regs(info->client,
LTC294X_REG_CURRENT_MSB, &datar[0], 2);
value = (datar[0] << 8) | datar[1];
value -= 0x7FFF;
/* Value is in range -32k..+32k, r_sense is usually 10..50 mOhm,
* the formula below keeps everything in s32 range while preserving
* enough digits */
*val = 1000 * ((60000 * value) / (info->r_sense * 0x7FFF)); /* in uA */
return ret;
}
static int ltc294x_reset(const struct ltc294x_info *info, int prescaler_exp)
{
int ret;
u8 value;
u8 control;
/* Read status and control registers */
ret = ltc294x_read_regs(info->client, LTC294X_REG_CONTROL, &value, 1);
if (ret < 0) {
dev_err(&info->client->dev,
"Could not read registers from device\n");
goto error_exit;
}
control = LTC294X_REG_CONTROL_PRESCALER_SET(prescaler_exp) |
LTC294X_REG_CONTROL_ALCC_CONFIG_DISABLED;
/* Put the 2943 into "monitor" mode, so it measures every 10 sec */
if (info->num_regs == LTC2943_NUM_REGS)
control |= LTC2943_REG_CONTROL_MODE_SCAN;
if (value != control) {
ret = ltc294x_write_regs(info->client,
LTC294X_REG_CONTROL, &control, 1);
if (ret < 0) {
dev_err(&info->client->dev,
"Could not write register\n");
goto error_exit;
}
}
return 0;
error_exit:
return ret;
}
static int ltc294x_get_voltage(const struct ltc294x_info *info, int *val)
{
int ret;
u8 datar[2];
u32 value;
ret = ltc294x_read_regs(info->client,
LTC294X_REG_VOLTAGE_MSB, &datar[0], 2);
value = (datar[0] << 8) | datar[1];
switch (info->id) {
case LTC2943_ID:
value *= 23600 * 2;
value /= 0xFFFF;
value *= 1000 / 2;
break;
case LTC2944_ID:
value *= 70800 / 5*4;
value /= 0xFFFF;
value *= 1000 * 5/4;
break;
default:
value *= 6000 * 10;
value /= 0xFFFF;
value *= 1000 / 10;
break;
}
*val = value;
return ret;
}
int ltc294x_reset( int prescaler_exp) {
struct ltc294x_info *info = <c2943_info;
int ret;
u8 value[3];
u8 control;
/* Read status and control registers */
ret = ltc294x_read_regs(info->client, LTC294X_REG_CONTROL, &value[0], 1);
if (ret < 0) {
dev_err(&info->client->dev,
"Could not read registers from device\n");
goto error_exit;
}
control = LTC294X_REG_CONTROL_PRESCALER_SET(prescaler_exp) |
LTC294X_REG_CONTROL_ALCC_CONFIG_OUTPUT_ALERT;
/* Set the 2943 mode*/
if (info->num_regs == LTC2943_NUM_REGS)
control |= LTC2943_REG_CONTROL_MODE_SCAN;
do {
if (value[0] != control) {
ret = ltc294x_write_regs(info->client,
LTC294X_REG_CONTROL, &control, 1);
if (ret < 0) {
dev_err(&info->client->dev,
"Could not write register\n");
goto error_exit;
}
}
/* Read status and control registers again */
ret = ltc294x_read_regs(info->client, LTC294X_REG_CONTROL, &value[0], 1);
if (ret < 0) {
dev_err(&info->client->dev,
"Could not read registers from device\n");
goto error_exit;
}
}
while(value[0]!= control);
return 0;
error_exit:
return ret;
}
static int ltc294x_read_charge_register(const struct ltc294x_info *info)
{
int ret;
u8 datar[2];
ret = ltc294x_read_regs(info->client,
LTC294X_REG_ACC_CHARGE_MSB, &datar[0], 2);
if (ret < 0)
return ret;
return (datar[0] << 8) + datar[1];
}
static int ltc294x_get_voltage(const struct ltc294x_info *info, int *val)
{
int ret;
u8 datar[2];
u32 value;
ret = ltc294x_read_regs(info->client,
LTC294X_REG_VOLTAGE_MSB, &datar[0], 2);
value = (datar[0] << 8) | datar[1];
*val = ((value * 23600) / 0xFFFF) * 1000; /* in uV */
return ret;
}
static int ltc294x_get_temperature(const struct ltc294x_info *info, int *val)
{
int ret;
u8 datar[2];
u32 value;
ret = ltc294x_read_regs(info->client,
LTC294X_REG_TEMPERATURE_MSB, &datar[0], 2);
value = (datar[0] << 8) | datar[1];
/* Full-scale is 510 Kelvin, convert to centidegrees */
*val = (((51000 * value) / 0xFFFF) - 27215);
return ret;
}
static int ltc294x_get_current(const struct ltc294x_info *info, int *val)
{
int ret;
u8 datar[2];
s32 value;
ret = ltc294x_read_regs(info->client,
LTC294X_REG_CURRENT_MSB, &datar[0], 2);
value = (datar[0] << 8) | datar[1];
value -= 0x7FFF;
/* Value is in range -32k..+32k, r_sense is usually 10..50 mOhm,
* the formula below keeps everything in s32 range while preserving
* enough digits */
*val = 1000 * ((60000 * value) / (info->r_sense * 0x7FFF)); /* in uA */
return ret;
}
static int ltc294x_reset(const struct ltc294x_info *info, int prescaler_exp)
{
int ret;
u8 value;
u8 control;
/* Read status and control registers */
ret = ltc294x_read_regs(info->client, LTC294X_REG_CONTROL, &value, 1);
if (ret < 0) {
dev_err(&info->client->dev,
"Could not read registers from device\n");
goto error_exit;
}
control = LTC294X_REG_CONTROL_PRESCALER_SET(prescaler_exp) |
LTC294X_REG_CONTROL_ALCC_CONFIG_DISABLED;
/* Put device into "monitor" mode */
switch (info->id) {
case LTC2942_ID: /* 2942 measures every 2 sec */
control |= LTC2942_REG_CONTROL_MODE_SCAN;
break;
case LTC2943_ID:
case LTC2944_ID: /* 2943 and 2944 measure every 10 sec */
control |= LTC2943_REG_CONTROL_MODE_SCAN;
break;
default:
break;
}
if (value != control) {
ret = ltc294x_write_regs(info->client,
LTC294X_REG_CONTROL, &control, 1);
if (ret < 0) {
dev_err(&info->client->dev,
"Could not write register\n");
goto error_exit;
}
}
return 0;
error_exit:
return ret;
}
static int ltc294x_get_temperature(const struct ltc294x_info *info, int *val)
{
enum ltc294x_reg reg;
int ret;
u8 datar[2];
u32 value;
if (info->id == LTC2942_ID) {
reg = LTC2942_REG_TEMPERATURE_MSB;
value = 60000; /* Full-scale is 600 Kelvin */
} else {
reg = LTC2943_REG_TEMPERATURE_MSB;
value = 51000; /* Full-scale is 510 Kelvin */
}
ret = ltc294x_read_regs(info->client, reg, &datar[0], 2);
value *= (datar[0] << 8) | datar[1];
/* Convert to centidegrees */
*val = value / 0xFFFF - 27215;
return ret;
}
static int ltc294x_set_charge_now(const struct ltc294x_info *info, int val)
{
int ret;
u8 dataw[2];
u8 ctrl_reg;
s32 value;
value = convert_uAh_to_bin(info, val);
/* Direction depends on how sense+/- were connected */
if (info->Qlsb < 0)
value += 0xFFFF;
if ((value < 0) || (value > 0xFFFF)) /* input validation */
return -EINVAL;
/* Read control register */
ret = ltc294x_read_regs(info->client,
LTC294X_REG_CONTROL, &ctrl_reg, 1);
if (ret < 0)
return ret;
/* Disable analog section */
ctrl_reg |= LTC294X_REG_CONTROL_SHUTDOWN_MASK;
ret = ltc294x_write_regs(info->client,
LTC294X_REG_CONTROL, &ctrl_reg, 1);
if (ret < 0)
return ret;
/* Set new charge value */
dataw[0] = I16_MSB(value);
dataw[1] = I16_LSB(value);
ret = ltc294x_write_regs(info->client,
LTC294X_REG_ACC_CHARGE_MSB, &dataw[0], 2);
if (ret < 0)
goto error_exit;
/* Enable analog section */
error_exit:
ctrl_reg &= ~LTC294X_REG_CONTROL_SHUTDOWN_MASK;
ret = ltc294x_write_regs(info->client,
LTC294X_REG_CONTROL, &ctrl_reg, 1);
return ret < 0 ? ret : 0;
}
static int ltc294x_i2c_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct ltc294x_platform_data *platform_data;
struct ltc294x_info *info;
int ret;
u32 prescaler_exp;
u8 status;
info = devm_kzalloc(&client->dev, sizeof(*info), GFP_KERNEL);
if (info == NULL)
return -ENOMEM;
i2c_set_clientdata(client, info);
platform_data = client->dev.platform_data;
info->id = (enum ltc294x_id)id->driver_data;
info->supply.name = platform_data->name;
/* r_sense can be negative, when sense+ is connected to the battery
* instead of the sense-. This results in reversed measurements. */
info->r_sense = platform_data->r_sense;
prescaler_exp = platform_data->prescaler_exp;
if (info->id == LTC2943_ID) {
if (prescaler_exp > LTC2943_MAX_PRESCALER_EXP)
prescaler_exp = LTC2943_MAX_PRESCALER_EXP;
info->Qlsb = ((340 * 50000) / info->r_sense) /
(4096 / (1 << (2*prescaler_exp)));
} else {
if (prescaler_exp > LTC2941_MAX_PRESCALER_EXP)
prescaler_exp = LTC2941_MAX_PRESCALER_EXP;
info->Qlsb = ((85 * 50000) / info->r_sense) /
(128 / (1 << prescaler_exp));
}
/* Read status register to check for LTC2942 */
if (info->id == LTC2941_ID || info->id == LTC2942_ID) {
ret = ltc294x_read_regs(client, LTC294X_REG_STATUS, &status, 1);
if (ret < 0) {
dev_err(&client->dev,
"Could not read status register\n");
return ret;
}
if (status & LTC2941_REG_STATUS_CHIP_ID)
info->id = LTC2941_ID;
else
info->id = LTC2942_ID;
}
info->client = client;
info->supply.type = POWER_SUPPLY_TYPE_BATTERY;
info->supply.properties = ltc294x_properties;
switch (info->id) {
case LTC2944_ID:
case LTC2943_ID:
info->supply.num_properties =
ARRAY_SIZE(ltc294x_properties);
break;
case LTC2942_ID:
info->supply.num_properties =
ARRAY_SIZE(ltc294x_properties) - 1;
break;
case LTC2941_ID:
default:
info->supply.num_properties =
ARRAY_SIZE(ltc294x_properties) - 3;
break;
}
info->supply.get_property = ltc294x_get_property;
info->supply.set_property = ltc294x_set_property;
info->supply.property_is_writeable = ltc294x_property_is_writeable;
info->supply.external_power_changed = NULL;
INIT_DELAYED_WORK(&info->work, ltc294x_work);
ret = ltc294x_reset(info, prescaler_exp);
if (ret < 0) {
dev_err(&client->dev, "Communication with chip failed\n");
return ret;
}
ret = power_supply_register(&client->dev, &info->supply);
if (ret) {
dev_err(&client->dev, "failed to register ltc2941\n");
return ret;
} else {
schedule_delayed_work(&info->work, LTC294X_WORK_DELAY * HZ);
}
return 0;
}
