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-rw-r--r--drivers/iio/humidity/hdc3020.c247
1 files changed, 247 insertions, 0 deletions
diff --git a/drivers/iio/humidity/hdc3020.c b/drivers/iio/humidity/hdc3020.c
index e42efe666e22..11ede97a31d7 100644
--- a/drivers/iio/humidity/hdc3020.c
+++ b/drivers/iio/humidity/hdc3020.c
@@ -5,38 +5,67 @@
*
* Copyright (C) 2023
*
+ * Copyright (C) 2024 Liebherr-Electronics and Drives GmbH
+ *
* Datasheet: https://www.ti.com/lit/ds/symlink/hdc3020.pdf
*/
+#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/cleanup.h>
#include <linux/crc8.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/init.h>
+#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/mutex.h>
+#include <linux/units.h>
#include <asm/unaligned.h>
+#include <linux/iio/events.h>
#include <linux/iio/iio.h>
#define HDC3020_S_AUTO_10HZ_MOD0 0x2737
+#define HDC3020_S_STATUS 0x3041
#define HDC3020_HEATER_DISABLE 0x3066
#define HDC3020_HEATER_ENABLE 0x306D
#define HDC3020_HEATER_CONFIG 0x306E
#define HDC3020_EXIT_AUTO 0x3093
+#define HDC3020_S_T_RH_THRESH_LOW 0x6100
+#define HDC3020_S_T_RH_THRESH_LOW_CLR 0x610B
+#define HDC3020_S_T_RH_THRESH_HIGH_CLR 0x6116
+#define HDC3020_S_T_RH_THRESH_HIGH 0x611D
#define HDC3020_R_T_RH_AUTO 0xE000
#define HDC3020_R_T_LOW_AUTO 0xE002
#define HDC3020_R_T_HIGH_AUTO 0xE003
#define HDC3020_R_RH_LOW_AUTO 0xE004
#define HDC3020_R_RH_HIGH_AUTO 0xE005
+#define HDC3020_R_T_RH_THRESH_LOW 0xE102
+#define HDC3020_R_T_RH_THRESH_LOW_CLR 0xE109
+#define HDC3020_R_T_RH_THRESH_HIGH_CLR 0xE114
+#define HDC3020_R_T_RH_THRESH_HIGH 0xE11F
+#define HDC3020_R_STATUS 0xF32D
+
+#define HDC3020_THRESH_TEMP_MASK GENMASK(8, 0)
+#define HDC3020_THRESH_TEMP_TRUNC_SHIFT 7
+#define HDC3020_THRESH_HUM_MASK GENMASK(15, 9)
+#define HDC3020_THRESH_HUM_TRUNC_SHIFT 9
+
+#define HDC3020_STATUS_T_LOW_ALERT BIT(6)
+#define HDC3020_STATUS_T_HIGH_ALERT BIT(7)
+#define HDC3020_STATUS_RH_LOW_ALERT BIT(8)
+#define HDC3020_STATUS_RH_HIGH_ALERT BIT(9)
#define HDC3020_READ_RETRY_TIMES 10
#define HDC3020_BUSY_DELAY_MS 10
#define HDC3020_CRC8_POLYNOMIAL 0x31
+#define HDC3020_MIN_TEMP -40
+#define HDC3020_MAX_TEMP 125
+
struct hdc3020_data {
struct i2c_client *client;
/*
@@ -50,18 +79,37 @@ struct hdc3020_data {
static const int hdc3020_heater_vals[] = {0, 1, 0x3FFF};
+static const struct iio_event_spec hdc3020_t_rh_event[] = {
+ {
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_RISING,
+ .mask_separate = BIT(IIO_EV_INFO_VALUE) |
+ BIT(IIO_EV_INFO_HYSTERESIS),
+ },
+ {
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_FALLING,
+ .mask_separate = BIT(IIO_EV_INFO_VALUE) |
+ BIT(IIO_EV_INFO_HYSTERESIS),
+ },
+};
+
static const struct iio_chan_spec hdc3020_channels[] = {
{
.type = IIO_TEMP,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_PEAK) |
BIT(IIO_CHAN_INFO_TROUGH) | BIT(IIO_CHAN_INFO_OFFSET),
+ .event_spec = hdc3020_t_rh_event,
+ .num_event_specs = ARRAY_SIZE(hdc3020_t_rh_event),
},
{
.type = IIO_HUMIDITYRELATIVE,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_PEAK) |
BIT(IIO_CHAN_INFO_TROUGH),
+ .event_spec = hdc3020_t_rh_event,
+ .num_event_specs = ARRAY_SIZE(hdc3020_t_rh_event),
},
{
/*
@@ -315,10 +363,192 @@ static int hdc3020_write_raw(struct iio_dev *indio_dev,
return -EINVAL;
}
+static int hdc3020_write_thresh(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ enum iio_event_type type,
+ enum iio_event_direction dir,
+ enum iio_event_info info,
+ int val, int val2)
+{
+ struct hdc3020_data *data = iio_priv(indio_dev);
+ u8 buf[5];
+ u64 tmp;
+ u16 reg;
+ int ret;
+
+ /* Supported temperature range is from –40 to 125 degree celsius */
+ if (val < HDC3020_MIN_TEMP || val > HDC3020_MAX_TEMP)
+ return -EINVAL;
+
+ /* Select threshold register */
+ if (info == IIO_EV_INFO_VALUE) {
+ if (dir == IIO_EV_DIR_RISING)
+ reg = HDC3020_S_T_RH_THRESH_HIGH;
+ else
+ reg = HDC3020_S_T_RH_THRESH_LOW;
+ } else {
+ if (dir == IIO_EV_DIR_RISING)
+ reg = HDC3020_S_T_RH_THRESH_HIGH_CLR;
+ else
+ reg = HDC3020_S_T_RH_THRESH_LOW_CLR;
+ }
+
+ guard(mutex)(&data->lock);
+ ret = hdc3020_read_be16(data, reg);
+ if (ret < 0)
+ return ret;
+
+ switch (chan->type) {
+ case IIO_TEMP:
+ /*
+ * Calculate temperature threshold, shift it down to get the
+ * truncated threshold representation in the 9LSBs while keeping
+ * the current humidity threshold in the 7 MSBs.
+ */
+ tmp = ((u64)(((val + 45) * MICRO) + val2)) * 65535ULL;
+ tmp = div_u64(tmp, MICRO * 175);
+ val = tmp >> HDC3020_THRESH_TEMP_TRUNC_SHIFT;
+ val = FIELD_PREP(HDC3020_THRESH_TEMP_MASK, val);
+ val |= (FIELD_GET(HDC3020_THRESH_HUM_MASK, ret) <<
+ HDC3020_THRESH_HUM_TRUNC_SHIFT);
+ break;
+ case IIO_HUMIDITYRELATIVE:
+ /*
+ * Calculate humidity threshold, shift it down and up to get the
+ * truncated threshold representation in the 7MSBs while keeping
+ * the current temperature threshold in the 9 LSBs.
+ */
+ tmp = ((u64)((val * MICRO) + val2)) * 65535ULL;
+ tmp = div_u64(tmp, MICRO * 100);
+ val = tmp >> HDC3020_THRESH_HUM_TRUNC_SHIFT;
+ val = FIELD_PREP(HDC3020_THRESH_HUM_MASK, val);
+ val |= FIELD_GET(HDC3020_THRESH_TEMP_MASK, ret);
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ put_unaligned_be16(reg, buf);
+ put_unaligned_be16(val, buf + 2);
+ buf[4] = crc8(hdc3020_crc8_table, buf + 2, 2, CRC8_INIT_VALUE);
+ return hdc3020_write_bytes(data, buf, 5);
+}
+
+static int hdc3020_read_thresh(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ enum iio_event_type type,
+ enum iio_event_direction dir,
+ enum iio_event_info info,
+ int *val, int *val2)
+{
+ struct hdc3020_data *data = iio_priv(indio_dev);
+ u16 reg;
+ int ret;
+
+ /* Select threshold register */
+ if (info == IIO_EV_INFO_VALUE) {
+ if (dir == IIO_EV_DIR_RISING)
+ reg = HDC3020_R_T_RH_THRESH_HIGH;
+ else
+ reg = HDC3020_R_T_RH_THRESH_LOW;
+ } else {
+ if (dir == IIO_EV_DIR_RISING)
+ reg = HDC3020_R_T_RH_THRESH_HIGH_CLR;
+ else
+ reg = HDC3020_R_T_RH_THRESH_LOW_CLR;
+ }
+
+ guard(mutex)(&data->lock);
+ ret = hdc3020_read_be16(data, reg);
+ if (ret < 0)
+ return ret;
+
+ switch (chan->type) {
+ case IIO_TEMP:
+ /*
+ * Get the temperature threshold from 9 LSBs, shift them to get
+ * the truncated temperature threshold representation and
+ * calculate the threshold according to the formula in the
+ * datasheet.
+ */
+ *val = FIELD_GET(HDC3020_THRESH_TEMP_MASK, ret);
+ *val = *val << HDC3020_THRESH_TEMP_TRUNC_SHIFT;
+ *val = -2949075 + (175 * (*val));
+ *val2 = 65535;
+ return IIO_VAL_FRACTIONAL;
+ case IIO_HUMIDITYRELATIVE:
+ /*
+ * Get the humidity threshold from 7 MSBs, shift them to get the
+ * truncated humidity threshold representation and calculate the
+ * threshold according to the formula in the datasheet.
+ */
+ *val = FIELD_GET(HDC3020_THRESH_HUM_MASK, ret);
+ *val = (*val << HDC3020_THRESH_HUM_TRUNC_SHIFT) * 100;
+ *val2 = 65535;
+ return IIO_VAL_FRACTIONAL;
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static irqreturn_t hdc3020_interrupt_handler(int irq, void *private)
+{
+ struct iio_dev *indio_dev = private;
+ struct hdc3020_data *data;
+ s64 time;
+ int ret;
+
+ data = iio_priv(indio_dev);
+ ret = hdc3020_read_be16(data, HDC3020_R_STATUS);
+ if (ret < 0)
+ return IRQ_HANDLED;
+
+ if (!(ret & (HDC3020_STATUS_T_HIGH_ALERT | HDC3020_STATUS_T_LOW_ALERT |
+ HDC3020_STATUS_RH_HIGH_ALERT | HDC3020_STATUS_RH_LOW_ALERT)))
+ return IRQ_NONE;
+
+ time = iio_get_time_ns(indio_dev);
+ if (ret & HDC3020_STATUS_T_HIGH_ALERT)
+ iio_push_event(indio_dev,
+ IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
+ IIO_NO_MOD,
+ IIO_EV_TYPE_THRESH,
+ IIO_EV_DIR_RISING),
+ time);
+
+ if (ret & HDC3020_STATUS_T_LOW_ALERT)
+ iio_push_event(indio_dev,
+ IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
+ IIO_NO_MOD,
+ IIO_EV_TYPE_THRESH,
+ IIO_EV_DIR_FALLING),
+ time);
+
+ if (ret & HDC3020_STATUS_RH_HIGH_ALERT)
+ iio_push_event(indio_dev,
+ IIO_MOD_EVENT_CODE(IIO_HUMIDITYRELATIVE, 0,
+ IIO_NO_MOD,
+ IIO_EV_TYPE_THRESH,
+ IIO_EV_DIR_RISING),
+ time);
+
+ if (ret & HDC3020_STATUS_RH_LOW_ALERT)
+ iio_push_event(indio_dev,
+ IIO_MOD_EVENT_CODE(IIO_HUMIDITYRELATIVE, 0,
+ IIO_NO_MOD,
+ IIO_EV_TYPE_THRESH,
+ IIO_EV_DIR_FALLING),
+ time);
+
+ return IRQ_HANDLED;
+}
+
static const struct iio_info hdc3020_info = {
.read_raw = hdc3020_read_raw,
.write_raw = hdc3020_write_raw,
.read_avail = hdc3020_read_available,
+ .read_event_value = hdc3020_read_thresh,
+ .write_event_value = hdc3020_write_thresh,
};
static void hdc3020_stop(void *data)
@@ -350,6 +580,23 @@ static int hdc3020_probe(struct i2c_client *client)
indio_dev->info = &hdc3020_info;
indio_dev->channels = hdc3020_channels;
indio_dev->num_channels = ARRAY_SIZE(hdc3020_channels);
+ if (client->irq) {
+ ret = devm_request_threaded_irq(&client->dev, client->irq,
+ NULL, hdc3020_interrupt_handler,
+ IRQF_ONESHOT, "hdc3020",
+ indio_dev);
+ if (ret)
+ return dev_err_probe(&client->dev, ret,
+ "Failed to request IRQ\n");
+
+ /*
+ * The alert output is activated by default upon power up,
+ * hardware reset, and soft reset. Clear the status register.
+ */
+ ret = hdc3020_exec_cmd(data, HDC3020_S_STATUS);
+ if (ret)
+ return ret;
+ }
ret = hdc3020_exec_cmd(data, HDC3020_S_AUTO_10HZ_MOD0);
if (ret)
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