[PATCH 2/8] iio: adc: axp20x_adc: add support for AXP813 ADC

From: Quentin Schulz
Date: Mon Dec 04 2017 - 09:17:16 EST


The X-Powers AXP813 PMIC is really close to what is already done for
AXP20X/AXP22X.

There are two pairs of bits to set the rate (one for Voltage and Current
measurements and one for TS/GPIO0 voltage measurements) instead of one.

The register to set the ADC rates is different from the one for
AXP20X/AXP22X.

GPIO0 can be used as an ADC (measuring Volts) unlike for AXP22X.

The scales to apply to the different inputs are unlike the ones from
AXP20X and AXP22X.

Signed-off-by: Quentin Schulz <quentin.schulz@xxxxxxxxxxxxxxxxxx>
---
drivers/iio/adc/axp20x_adc.c | 122 ++++++++++++++++++++++++++++++++++++-
include/linux/mfd/axp20x.h | 2 +-
2 files changed, 124 insertions(+)

diff --git a/drivers/iio/adc/axp20x_adc.c b/drivers/iio/adc/axp20x_adc.c
index 7274f4f..03d489b 100644
--- a/drivers/iio/adc/axp20x_adc.c
+++ b/drivers/iio/adc/axp20x_adc.c
@@ -35,8 +35,13 @@
#define AXP20X_GPIO10_IN_RANGE_GPIO1_VAL(x) (((x) & BIT(0)) << 1)

#define AXP20X_ADC_RATE_MASK GENMASK(7, 6)
+#define AXP813_V_I_ADC_RATE_MASK GENMASK(5, 4)
+#define AXP813_ADC_RATE_MASK (AXP20X_ADC_RATE_MASK | AXP813_V_I_ADC_RATE_MASK)
#define AXP20X_ADC_RATE_HZ(x) ((ilog2((x) / 25) << 6) & AXP20X_ADC_RATE_MASK)
#define AXP22X_ADC_RATE_HZ(x) ((ilog2((x) / 100) << 6) & AXP20X_ADC_RATE_MASK)
+#define AXP813_TS_GPIO0_ADC_RATE_HZ(x) AXP20X_ADC_RATE_HZ(x)
+#define AXP813_V_I_ADC_RATE_HZ(x) ((ilog2((x) / 100) << 4) & AXP813_V_I_ADC_RATE_MASK)
+#define AXP813_ADC_RATE_HZ(x) (AXP20X_ADC_RATE_HZ(x) | AXP813_V_I_ADC_RATE_HZ(x))

#define AXP20X_ADC_CHANNEL(_channel, _name, _type, _reg) \
{ \
@@ -95,6 +100,12 @@ enum axp22x_adc_channel_i {
AXP22X_BATT_DISCHRG_I,
};

+enum axp813_adc_channel_v {
+ AXP813_TS_IN = 0,
+ AXP813_GPIO0_V,
+ AXP813_BATT_V,
+};
+
static struct iio_map axp20x_maps[] = {
{
.consumer_dev_name = "axp20x-usb-power-supply",
@@ -197,6 +208,25 @@ static const struct iio_chan_spec axp22x_adc_channels[] = {
AXP20X_BATT_DISCHRG_I_H),
};

+static const struct iio_chan_spec axp813_adc_channels[] = {
+ {
+ .type = IIO_TEMP,
+ .address = AXP22X_PMIC_TEMP_H,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_OFFSET),
+ .datasheet_name = "pmic_temp",
+ },
+ AXP20X_ADC_CHANNEL(AXP813_GPIO0_V, "gpio0_v", IIO_VOLTAGE,
+ AXP288_GP_ADC_H),
+ AXP20X_ADC_CHANNEL(AXP813_BATT_V, "batt_v", IIO_VOLTAGE,
+ AXP20X_BATT_V_H),
+ AXP20X_ADC_CHANNEL(AXP22X_BATT_CHRG_I, "batt_chrg_i", IIO_CURRENT,
+ AXP20X_BATT_CHRG_I_H),
+ AXP20X_ADC_CHANNEL(AXP22X_BATT_DISCHRG_I, "batt_dischrg_i", IIO_CURRENT,
+ AXP20X_BATT_DISCHRG_I_H),
+};
+
static int axp20x_adc_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int *val)
{
@@ -243,6 +273,18 @@ static int axp22x_adc_raw(struct iio_dev *indio_dev,
return IIO_VAL_INT;
}

+static int axp813_adc_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int *val)
+{
+ struct axp20x_adc_iio *info = iio_priv(indio_dev);
+
+ *val = axp20x_read_variable_width(info->regmap, chan->address, 12);
+ if (*val < 0)
+ return *val;
+
+ return IIO_VAL_INT;
+}
+
static int axp20x_adc_scale_voltage(int channel, int *val, int *val2)
{
switch (channel) {
@@ -273,6 +315,24 @@ static int axp20x_adc_scale_voltage(int channel, int *val, int *val2)
}
}

+static int axp813_adc_scale_voltage(int channel, int *val, int *val2)
+{
+ switch (channel) {
+ case AXP813_GPIO0_V:
+ *val = 0;
+ *val2 = 800000;
+ return IIO_VAL_INT_PLUS_MICRO;
+
+ case AXP813_BATT_V:
+ *val = 1;
+ *val2 = 100000;
+ return IIO_VAL_INT_PLUS_MICRO;
+
+ default:
+ return -EINVAL;
+ }
+}
+
static int axp20x_adc_scale_current(int channel, int *val, int *val2)
{
switch (channel) {
@@ -342,6 +402,26 @@ static int axp22x_adc_scale(struct iio_chan_spec const *chan, int *val,
}
}

+static int axp813_adc_scale(struct iio_chan_spec const *chan, int *val,
+ int *val2)
+{
+ switch (chan->type) {
+ case IIO_VOLTAGE:
+ return axp813_adc_scale_voltage(chan->channel, val, val2);
+
+ case IIO_CURRENT:
+ *val = 1;
+ return IIO_VAL_INT;
+
+ case IIO_TEMP:
+ *val = 100;
+ return IIO_VAL_INT;
+
+ default:
+ return -EINVAL;
+ }
+}
+
static int axp20x_adc_offset_voltage(struct iio_dev *indio_dev, int channel,
int *val)
{
@@ -425,6 +505,26 @@ static int axp22x_read_raw(struct iio_dev *indio_dev,
}
}

+static int axp813_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int *val,
+ int *val2, long mask)
+{
+ switch (mask) {
+ case IIO_CHAN_INFO_OFFSET:
+ *val = -2667;
+ return IIO_VAL_INT;
+
+ case IIO_CHAN_INFO_SCALE:
+ return axp813_adc_scale(chan, val, val2);
+
+ case IIO_CHAN_INFO_RAW:
+ return axp813_adc_raw(indio_dev, chan, val);
+
+ default:
+ return -EINVAL;
+ }
+}
+
static int axp20x_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int val, int val2,
long mask)
@@ -470,6 +570,10 @@ static const struct iio_info axp22x_adc_iio_info = {
.read_raw = axp22x_read_raw,
};

+static const struct iio_info axp813_adc_iio_info = {
+ .read_raw = axp813_read_raw,
+};
+
static int axp20x_adc_rate(struct axp20x_adc_iio *info, int rate)
{
return regmap_update_bits(info->regmap, AXP20X_ADC_RATE,
@@ -484,6 +588,13 @@ static int axp22x_adc_rate(struct axp20x_adc_iio *info, int rate)
AXP22X_ADC_RATE_HZ(rate));
}

+static int axp813_adc_rate(struct axp20x_adc_iio *info, int rate)
+{
+ return regmap_update_bits(info->regmap, AXP813_ADC_RATE,
+ AXP813_ADC_RATE_MASK,
+ AXP813_ADC_RATE_HZ(rate));
+}
+
struct axp_data {
const struct iio_info *iio_info;
int num_channels;
@@ -514,9 +625,20 @@ static const struct axp_data axp22x_data = {
.maps = axp22x_maps,
};

+static const struct axp_data axp813_data = {
+ .iio_info = &axp813_adc_iio_info,
+ .num_channels = ARRAY_SIZE(axp813_adc_channels),
+ .channels = axp813_adc_channels,
+ .adc_en1_mask = AXP22X_ADC_EN1_MASK,
+ .adc_rate = axp813_adc_rate,
+ .adc_en2 = false,
+ .maps = axp22x_maps,
+};
+
static const struct platform_device_id axp20x_adc_id_match[] = {
{ .name = "axp20x-adc", .driver_data = (kernel_ulong_t)&axp20x_data, },
{ .name = "axp22x-adc", .driver_data = (kernel_ulong_t)&axp22x_data, },
+ { .name = "axp813-adc", .driver_data = (kernel_ulong_t)&axp813_data, },
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(platform, axp20x_adc_id_match);
diff --git a/include/linux/mfd/axp20x.h b/include/linux/mfd/axp20x.h
index 78dc853..ff95414 100644
--- a/include/linux/mfd/axp20x.h
+++ b/include/linux/mfd/axp20x.h
@@ -266,6 +266,8 @@ enum axp20x_variants {
#define AXP288_RT_BATT_V_H 0xa0
#define AXP288_RT_BATT_V_L 0xa1

+#define AXP813_ADC_RATE 0x85
+
/* Fuel Gauge */
#define AXP288_FG_RDC1_REG 0xba
#define AXP288_FG_RDC0_REG 0xbb
--
git-series 0.9.1