These measurements for ACIN (adapter input) are just the momentary values sampled from ADC. But in order to have something more practical, a lot of values need to be sampled and averaged. Just obtaining a single output from the 'sensors' tool is not very meaningful, because the momentary current draw changes very fast and within a rather wide range (jumping up and down +-50% is not very uncommon).
To make accurate measurements possible at least from the userland, it is unreasonable to limit the frequency of sysfs hwmon entries update to just one read per two seconds. So this limitation has been relaxed to allow polling at 50Hz. Signed-off-by: Siarhei Siamashka <[email protected]> --- drivers/power/axp_power/axp20-mfd.h | 91 +++++++++++++++++++++++++++++++------ include/linux/mfd/axp-mfd.h | 3 ++ 2 files changed, 80 insertions(+), 14 deletions(-) diff --git a/drivers/power/axp_power/axp20-mfd.h b/drivers/power/axp_power/axp20-mfd.h index 6ec26f6..8d679ac 100644 --- a/drivers/power/axp_power/axp20-mfd.h +++ b/drivers/power/axp_power/axp20-mfd.h @@ -44,17 +44,60 @@ show_temp(struct device *dev, struct device_attribute *devattr, char *buf) return sprintf(buf, "%d\n", data->temperature * 100); } +static ssize_t +show_acin_voltage(struct device *dev, struct device_attribute *devattr, + char *buf) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); + struct axp_mfd_chip *data = axp20_update_device(dev); + if (attr->index == 3) + return sprintf(buf, "ACIN voltage\n"); + return sprintf(buf, "%d\n", data->acin_voltage); +} + +static ssize_t +show_acin_current(struct device *dev, struct device_attribute *devattr, + char *buf) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); + struct axp_mfd_chip *data = axp20_update_device(dev); + if (attr->index == 3) + return sprintf(buf, "ACIN current\n"); + return sprintf(buf, "%d\n", data->acin_current); +} + +static ssize_t +show_acin_power(struct device *dev, struct device_attribute *devattr, char *buf) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); + struct axp_mfd_chip *data = axp20_update_device(dev); + if (attr->index == 3) + return sprintf(buf, "ACIN power\n"); + return sprintf(buf, "%d\n", data->acin_power); +} static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0); static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp, NULL, 1); static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO, show_temp, NULL, 2); static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_temp, NULL, 3); +static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, show_acin_voltage, NULL, 0); +static SENSOR_DEVICE_ATTR(in0_label, S_IRUGO, show_acin_voltage, NULL, 3); +static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, show_acin_current, NULL, 0); +static SENSOR_DEVICE_ATTR(curr1_label, S_IRUGO, show_acin_current, NULL, 3); +static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, show_acin_power, NULL, 0); +static SENSOR_DEVICE_ATTR(power1_label, S_IRUGO, show_acin_power, NULL, 3); static struct attribute *axp20_attributes[] = { &sensor_dev_attr_temp1_input.dev_attr.attr, &sensor_dev_attr_temp1_min.dev_attr.attr, &sensor_dev_attr_temp1_max.dev_attr.attr, &sensor_dev_attr_temp1_label.dev_attr.attr, + &sensor_dev_attr_in0_input.dev_attr.attr, + &sensor_dev_attr_in0_label.dev_attr.attr, + &sensor_dev_attr_curr1_input.dev_attr.attr, + &sensor_dev_attr_curr1_label.dev_attr.attr, + &sensor_dev_attr_power1_input.dev_attr.attr, + &sensor_dev_attr_power1_label.dev_attr.attr, NULL }; @@ -62,6 +105,25 @@ static const struct attribute_group axp20_group = { .attrs = axp20_attributes, }; +static int axp_read_adc(struct device *dev, struct i2c_client *client, int reg) +{ + int err; + u8 high, low; + + err = __axp_read(client, reg, &high); + if (err) { + dev_err(dev, "AXP Error while reading REG 0x%02X\n", reg); + high = 0; + } + + err = __axp_read(client, reg + 1, &low); + if (err) { + dev_err(dev, "AXP Error while reading REG 0x%02X\n", reg + 1); + low = 0; + } + + return (high << 4) + (low & 0x0F); +} /* * * function that update the status of the chips (temperature) @@ -70,29 +132,30 @@ static struct axp_mfd_chip *axp20_update_device(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); struct axp_mfd_chip *data = i2c_get_clientdata(client); - int err; - u8 high, low; + int adc_value; mutex_lock(&data->lock); - if (time_after(jiffies, data->last_updated + HZ * 2) + if (time_after(jiffies, data->last_updated + HZ / 50) || !data->valid) { dev_dbg(&client->dev, "Updating axp20 data\n"); + /* AXP202 datasheet page 25, 0x000 means -144.7, * 0xfff means 264.8, 4096 steps of 0.1 degress */ - err = __axp_read(client, 0x5E, &high); - if (err) { - dev_err(dev, "AXP Error while reading high\n"); - high = 0; - } + data->temperature = -1447 + axp_read_adc(dev, client, 0x5E); - err = __axp_read(client, 0x5F, &low); - if (err) { - dev_err(dev, "AXP Error while reading low\n"); - low = 0; - } + /* AXP202 datasheet page 25, 0x000 means 0V, + * 0xfff means 6.9615V, 4096 steps of 1.7mV */ + adc_value = axp_read_adc(dev, client, 0x56); + data->acin_voltage = adc_value * 111411 >> 16; + + /* AXP202 datasheet page 25, 0x000 means 0A, + * 0xfff means 2.5594A, 4096 steps of 0.625mA */ + adc_value = axp_read_adc(dev, client, 0x58); + data->acin_current = adc_value * 40960 >> 16; + + data->acin_power = data->acin_voltage * data->acin_current; - data->temperature = -1447 + ((high << 4) + (low & 0x0F)); data->last_updated = jiffies; data->valid = 1; } diff --git a/include/linux/mfd/axp-mfd.h b/include/linux/mfd/axp-mfd.h index 6e6843d..1226d17 100644 --- a/include/linux/mfd/axp-mfd.h +++ b/include/linux/mfd/axp-mfd.h @@ -133,6 +133,9 @@ struct axp_mfd_chip { struct blocking_notifier_head notifier_list; #ifdef CONFIG_AXP_HWMON s16 temperature; /* range from -1447 to 2648 */ + s16 acin_voltage; /* range from 0 to 6962 mV */ + s16 acin_current; /* range from 0 to 2559 mA */ + s32 acin_power; unsigned long last_updated; /* in jiffies */ char valid; /* zero until following fields are valid */ struct device *hwmon_dev; -- 1.8.3.2 -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
