diff options
Diffstat (limited to 'drivers/iio/humidity/hdc3020.c')
| -rw-r--r-- | drivers/iio/humidity/hdc3020.c | 905 |
1 files changed, 905 insertions, 0 deletions
diff --git a/drivers/iio/humidity/hdc3020.c b/drivers/iio/humidity/hdc3020.c new file mode 100644 index 000000000000..78b2c171c8da --- /dev/null +++ b/drivers/iio/humidity/hdc3020.c @@ -0,0 +1,905 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * hdc3020.c - Support for the TI HDC3020,HDC3021 and HDC3022 + * temperature + relative humidity sensors + * + * 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/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/math64.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/pm.h> +#include <linux/regulator/consumer.h> +#include <linux/units.h> + +#include <linux/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_MICRO -39872968 +#define HDC3020_MAX_TEMP_MICRO 124875639 +#define HDC3020_MAX_TEMP_HYST_MICRO 164748607 +#define HDC3020_MAX_HUM_MICRO 99220264 + +/* Divide 65535 from the datasheet by 5 to avoid overflows */ +#define HDC3020_THRESH_FRACTION (65535 / 5) + +struct hdc3020_data { + struct i2c_client *client; + struct gpio_desc *reset_gpio; + struct regulator *vdd_supply; + /* + * Ensure that the sensor configuration (currently only heater is + * supported) will not be changed during the process of reading + * sensor data (this driver will try HDC3020_READ_RETRY_TIMES times + * if the device does not respond). + */ + struct mutex lock; +}; + +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), + }, + { + /* + * For setting the internal heater, which can be switched on to + * prevent or remove any condensation that may develop when the + * ambient environment approaches its dew point temperature. + */ + .type = IIO_CURRENT, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW), + .output = 1, + }, +}; + +DECLARE_CRC8_TABLE(hdc3020_crc8_table); + +static int hdc3020_write_bytes(struct hdc3020_data *data, u8 *buf, u8 len) +{ + struct i2c_client *client = data->client; + struct i2c_msg msg; + int ret, cnt; + + msg.addr = client->addr; + msg.flags = 0; + msg.buf = buf; + msg.len = len; + + /* + * During the measurement process, HDC3020 will not return data. + * So wait for a while and try again + */ + for (cnt = 0; cnt < HDC3020_READ_RETRY_TIMES; cnt++) { + ret = i2c_transfer(client->adapter, &msg, 1); + if (ret == 1) + return 0; + + mdelay(HDC3020_BUSY_DELAY_MS); + } + dev_err(&client->dev, "Could not write sensor command\n"); + + return -ETIMEDOUT; +} + +static +int hdc3020_read_bytes(struct hdc3020_data *data, u16 reg, u8 *buf, int len) +{ + u8 reg_buf[2]; + int ret, cnt; + struct i2c_client *client = data->client; + struct i2c_msg msg[2] = { + [0] = { + .addr = client->addr, + .flags = 0, + .buf = reg_buf, + .len = 2, + }, + [1] = { + .addr = client->addr, + .flags = I2C_M_RD, + .buf = buf, + .len = len, + }, + }; + + put_unaligned_be16(reg, reg_buf); + /* + * During the measurement process, HDC3020 will not return data. + * So wait for a while and try again + */ + for (cnt = 0; cnt < HDC3020_READ_RETRY_TIMES; cnt++) { + ret = i2c_transfer(client->adapter, msg, 2); + if (ret == 2) + return 0; + + mdelay(HDC3020_BUSY_DELAY_MS); + } + dev_err(&client->dev, "Could not read sensor data\n"); + + return -ETIMEDOUT; +} + +static int hdc3020_read_be16(struct hdc3020_data *data, u16 reg) +{ + u8 crc, buf[3]; + int ret; + + ret = hdc3020_read_bytes(data, reg, buf, 3); + if (ret < 0) + return ret; + + crc = crc8(hdc3020_crc8_table, buf, 2, CRC8_INIT_VALUE); + if (crc != buf[2]) + return -EINVAL; + + return get_unaligned_be16(buf); +} + +static int hdc3020_exec_cmd(struct hdc3020_data *data, u16 reg) +{ + u8 reg_buf[2]; + + put_unaligned_be16(reg, reg_buf); + return hdc3020_write_bytes(data, reg_buf, 2); +} + +static int hdc3020_read_measurement(struct hdc3020_data *data, + enum iio_chan_type type, int *val) +{ + u8 crc, buf[6]; + int ret; + + ret = hdc3020_read_bytes(data, HDC3020_R_T_RH_AUTO, buf, 6); + if (ret < 0) + return ret; + + /* CRC check of the temperature measurement */ + crc = crc8(hdc3020_crc8_table, buf, 2, CRC8_INIT_VALUE); + if (crc != buf[2]) + return -EINVAL; + + /* CRC check of the relative humidity measurement */ + crc = crc8(hdc3020_crc8_table, buf + 3, 2, CRC8_INIT_VALUE); + if (crc != buf[5]) + return -EINVAL; + + if (type == IIO_TEMP) + *val = get_unaligned_be16(buf); + else if (type == IIO_HUMIDITYRELATIVE) + *val = get_unaligned_be16(&buf[3]); + else + return -EINVAL; + + return 0; +} + +static int hdc3020_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, + int *val2, long mask) +{ + struct hdc3020_data *data = iio_priv(indio_dev); + int ret; + + if (chan->type != IIO_TEMP && chan->type != IIO_HUMIDITYRELATIVE) + return -EINVAL; + + switch (mask) { + case IIO_CHAN_INFO_RAW: { + guard(mutex)(&data->lock); + ret = hdc3020_read_measurement(data, chan->type, val); + if (ret < 0) + return ret; + + return IIO_VAL_INT; + } + case IIO_CHAN_INFO_PEAK: { + guard(mutex)(&data->lock); + if (chan->type == IIO_TEMP) + ret = hdc3020_read_be16(data, HDC3020_R_T_HIGH_AUTO); + else + ret = hdc3020_read_be16(data, HDC3020_R_RH_HIGH_AUTO); + + if (ret < 0) + return ret; + + *val = ret; + return IIO_VAL_INT; + } + case IIO_CHAN_INFO_TROUGH: { + guard(mutex)(&data->lock); + if (chan->type == IIO_TEMP) + ret = hdc3020_read_be16(data, HDC3020_R_T_LOW_AUTO); + else + ret = hdc3020_read_be16(data, HDC3020_R_RH_LOW_AUTO); + + if (ret < 0) + return ret; + + *val = ret; + return IIO_VAL_INT; + } + case IIO_CHAN_INFO_SCALE: + *val2 = 65536; + if (chan->type == IIO_TEMP) + *val = 175 * MILLI; + else + *val = 100 * MILLI; + return IIO_VAL_FRACTIONAL; + + case IIO_CHAN_INFO_OFFSET: + if (chan->type != IIO_TEMP) + return -EINVAL; + + *val = -16852; + return IIO_VAL_INT; + + default: + return -EINVAL; + } +} + +static int hdc3020_read_available(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int **vals, + int *type, int *length, long mask) +{ + if (mask != IIO_CHAN_INFO_RAW || chan->type != IIO_CURRENT) + return -EINVAL; + + *vals = hdc3020_heater_vals; + *type = IIO_VAL_INT; + + return IIO_AVAIL_RANGE; +} + +static int hdc3020_update_heater(struct hdc3020_data *data, int val) +{ + u8 buf[5]; + int ret; + + if (val < hdc3020_heater_vals[0] || val > hdc3020_heater_vals[2]) + return -EINVAL; + + if (!val) + hdc3020_exec_cmd(data, HDC3020_HEATER_DISABLE); + + put_unaligned_be16(HDC3020_HEATER_CONFIG, buf); + put_unaligned_be16(val & GENMASK(13, 0), &buf[2]); + buf[4] = crc8(hdc3020_crc8_table, buf + 2, 2, CRC8_INIT_VALUE); + ret = hdc3020_write_bytes(data, buf, 5); + if (ret < 0) + return ret; + + return hdc3020_exec_cmd(data, HDC3020_HEATER_ENABLE); +} + +static int hdc3020_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct hdc3020_data *data = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_RAW: + if (chan->type != IIO_CURRENT) + return -EINVAL; + + guard(mutex)(&data->lock); + return hdc3020_update_heater(data, val); + } + + return -EINVAL; +} + +static int hdc3020_thresh_get_temp(u16 thresh) +{ + int temp; + + /* + * Get the temperature threshold from 9 LSBs, shift them to get the + * truncated temperature threshold representation and calculate the + * threshold according to the explicit formula in the datasheet: + * T(C) = -45 + (175 * temp) / 65535. + * Additionally scale by HDC3020_THRESH_FRACTION to avoid precision loss + * when calculating threshold and hysteresis values. Result is degree + * celsius scaled by HDC3020_THRESH_FRACTION. + */ + temp = FIELD_GET(HDC3020_THRESH_TEMP_MASK, thresh) << + HDC3020_THRESH_TEMP_TRUNC_SHIFT; + + return -2949075 / 5 + (175 / 5 * temp); +} + +static int hdc3020_thresh_get_hum(u16 thresh) +{ + int hum; + + /* + * Get the humidity threshold from 7 MSBs, shift them to get the + * truncated humidity threshold representation and calculate the + * threshold according to the explicit formula in the datasheet: + * RH(%) = 100 * hum / 65535. + * Additionally scale by HDC3020_THRESH_FRACTION to avoid precision loss + * when calculating threshold and hysteresis values. Result is percent + * scaled by HDC3020_THRESH_FRACTION. + */ + hum = FIELD_GET(HDC3020_THRESH_HUM_MASK, thresh) << + HDC3020_THRESH_HUM_TRUNC_SHIFT; + + return hum * 100 / 5; +} + +static u16 hdc3020_thresh_set_temp(int s_temp, u16 curr_thresh) +{ + u64 temp; + u16 thresh; + + /* + * 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. + */ + temp = (u64)(s_temp + 45000000) * 65535ULL; + temp = div_u64(temp, 1000000 * 175) >> HDC3020_THRESH_TEMP_TRUNC_SHIFT; + thresh = FIELD_PREP(HDC3020_THRESH_TEMP_MASK, temp); + thresh |= (FIELD_GET(HDC3020_THRESH_HUM_MASK, curr_thresh) << + HDC3020_THRESH_HUM_TRUNC_SHIFT); + + return thresh; +} + +static u16 hdc3020_thresh_set_hum(int s_hum, u16 curr_thresh) +{ + u64 hum; + u16 thresh; + + /* + * 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. + */ + hum = (u64)(s_hum) * 65535ULL; + hum = div_u64(hum, 1000000 * 100) >> HDC3020_THRESH_HUM_TRUNC_SHIFT; + thresh = FIELD_PREP(HDC3020_THRESH_HUM_MASK, hum); + thresh |= FIELD_GET(HDC3020_THRESH_TEMP_MASK, curr_thresh); + + return thresh; +} + +static +int hdc3020_thresh_clr(s64 s_thresh, s64 s_hyst, enum iio_event_direction dir) +{ + s64 s_clr; + + /* + * Include directions when calculation the clear value, + * since hysteresis is unsigned by definition and the + * clear value is an absolute value which is signed. + */ + if (dir == IIO_EV_DIR_RISING) + s_clr = s_thresh - s_hyst; + else + s_clr = s_thresh + s_hyst; + + /* Divide by HDC3020_THRESH_FRACTION to get units of micro */ + return div_s64(s_clr, HDC3020_THRESH_FRACTION); +} + +static int _hdc3020_write_thresh(struct hdc3020_data *data, u16 reg, u16 val) +{ + u8 buf[5]; + + 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_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); + u16 reg, reg_val, reg_thresh_rd, reg_clr_rd, reg_thresh_wr, reg_clr_wr; + s64 s_thresh, s_hyst, s_clr; + int s_val, thresh, clr, ret; + + /* Select threshold registers */ + if (dir == IIO_EV_DIR_RISING) { + reg_thresh_rd = HDC3020_R_T_RH_THRESH_HIGH; + reg_thresh_wr = HDC3020_S_T_RH_THRESH_HIGH; + reg_clr_rd = HDC3020_R_T_RH_THRESH_HIGH_CLR; + reg_clr_wr = HDC3020_S_T_RH_THRESH_HIGH_CLR; + } else { + reg_thresh_rd = HDC3020_R_T_RH_THRESH_LOW; + reg_thresh_wr = HDC3020_S_T_RH_THRESH_LOW; + reg_clr_rd = HDC3020_R_T_RH_THRESH_LOW_CLR; + reg_clr_wr = HDC3020_S_T_RH_THRESH_LOW_CLR; + } + + guard(mutex)(&data->lock); + ret = hdc3020_read_be16(data, reg_thresh_rd); + if (ret < 0) + return ret; + + thresh = ret; + ret = hdc3020_read_be16(data, reg_clr_rd); + if (ret < 0) + return ret; + + clr = ret; + /* Scale value to include decimal part into calculations */ + s_val = (val < 0) ? (val * 1000 - val2) : (val * 1000 + val2); + switch (chan->type) { + case IIO_TEMP: + switch (info) { + case IIO_EV_INFO_VALUE: + s_val = max(s_val, HDC3020_MIN_TEMP_MICRO); + s_val = min(s_val, HDC3020_MAX_TEMP_MICRO); + reg = reg_thresh_wr; + reg_val = hdc3020_thresh_set_temp(s_val, thresh); + ret = _hdc3020_write_thresh(data, reg, reg_val); + if (ret < 0) + return ret; + + /* Calculate old hysteresis */ + s_thresh = (s64)hdc3020_thresh_get_temp(thresh) * 1000000; + s_clr = (s64)hdc3020_thresh_get_temp(clr) * 1000000; + s_hyst = div_s64(abs(s_thresh - s_clr), + HDC3020_THRESH_FRACTION); + /* Set new threshold */ + thresh = reg_val; + /* Set old hysteresis */ + s_val = s_hyst; + fallthrough; + case IIO_EV_INFO_HYSTERESIS: + /* + * Function hdc3020_thresh_get_temp returns temperature + * in degree celsius scaled by HDC3020_THRESH_FRACTION. + * Scale by 1000000 to be able to subtract scaled + * hysteresis value. + */ + s_thresh = (s64)hdc3020_thresh_get_temp(thresh) * 1000000; + /* + * Units of s_val are in micro degree celsius, scale by + * HDC3020_THRESH_FRACTION to get same units as s_thresh. + */ + s_val = min(abs(s_val), HDC3020_MAX_TEMP_HYST_MICRO); + s_hyst = (s64)s_val * HDC3020_THRESH_FRACTION; + s_clr = hdc3020_thresh_clr(s_thresh, s_hyst, dir); + s_clr = max(s_clr, HDC3020_MIN_TEMP_MICRO); + s_clr = min(s_clr, HDC3020_MAX_TEMP_MICRO); + reg = reg_clr_wr; + reg_val = hdc3020_thresh_set_temp(s_clr, clr); + break; + default: + return -EOPNOTSUPP; + } + break; + case IIO_HUMIDITYRELATIVE: + s_val = (s_val < 0) ? 0 : min(s_val, HDC3020_MAX_HUM_MICRO); + switch (info) { + case IIO_EV_INFO_VALUE: + reg = reg_thresh_wr; + reg_val = hdc3020_thresh_set_hum(s_val, thresh); + ret = _hdc3020_write_thresh(data, reg, reg_val); + if (ret < 0) + return ret; + + /* Calculate old hysteresis */ + s_thresh = (s64)hdc3020_thresh_get_hum(thresh) * 1000000; + s_clr = (s64)hdc3020_thresh_get_hum(clr) * 1000000; + s_hyst = div_s64(abs(s_thresh - s_clr), + HDC3020_THRESH_FRACTION); + /* Set new threshold */ + thresh = reg_val; + /* Try to set old hysteresis */ + s_val = min(abs(s_hyst), HDC3020_MAX_HUM_MICRO); + fallthrough; + case IIO_EV_INFO_HYSTERESIS: + /* + * Function hdc3020_thresh_get_hum returns relative + * humidity in percent scaled by HDC3020_THRESH_FRACTION. + * Scale by 1000000 to be able to subtract scaled + * hysteresis value. + */ + s_thresh = (s64)hdc3020_thresh_get_hum(thresh) * 1000000; + /* + * Units of s_val are in micro percent, scale by + * HDC3020_THRESH_FRACTION to get same units as s_thresh. + */ + s_hyst = (s64)s_val * HDC3020_THRESH_FRACTION; + s_clr = hdc3020_thresh_clr(s_thresh, s_hyst, dir); + s_clr = max(s_clr, 0); + s_clr = min(s_clr, HDC3020_MAX_HUM_MICRO); + reg = reg_clr_wr; + reg_val = hdc3020_thresh_set_hum(s_clr, clr); + break; + default: + return -EOPNOTSUPP; + } + break; + default: + return -EOPNOTSUPP; + } + + return _hdc3020_write_thresh(data, reg, reg_val); +} + +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_thresh, reg_clr; + int thresh, clr, ret; + + /* Select threshold registers */ + if (dir == IIO_EV_DIR_RISING) { + reg_thresh = HDC3020_R_T_RH_THRESH_HIGH; + reg_clr = HDC3020_R_T_RH_THRESH_HIGH_CLR; + } else { + reg_thresh = HDC3020_R_T_RH_THRESH_LOW; + reg_clr = HDC3020_R_T_RH_THRESH_LOW_CLR; + } + + guard(mutex)(&data->lock); + ret = hdc3020_read_be16(data, reg_thresh); + if (ret < 0) + return ret; + + switch (chan->type) { + case IIO_TEMP: + thresh = hdc3020_thresh_get_temp(ret); + switch (info) { + case IIO_EV_INFO_VALUE: + *val = thresh * MILLI; + break; + case IIO_EV_INFO_HYSTERESIS: + ret = hdc3020_read_be16(data, reg_clr); + if (ret < 0) + return ret; + + clr = hdc3020_thresh_get_temp(ret); + *val = abs(thresh - clr) * MILLI; + break; + default: + return -EOPNOTSUPP; + } + *val2 = HDC3020_THRESH_FRACTION; + return IIO_VAL_FRACTIONAL; + case IIO_HUMIDITYRELATIVE: + thresh = hdc3020_thresh_get_hum(ret); + switch (info) { + case IIO_EV_INFO_VALUE: + *val = thresh * MILLI; + break; + case IIO_EV_INFO_HYSTERESIS: + ret = hdc3020_read_be16(data, reg_clr); + if (ret < 0) + return ret; + + clr = hdc3020_thresh_get_hum(ret); + *val = abs(thresh - clr) * MILLI; + break; + default: + return -EOPNOTSUPP; + } + *val2 = HDC3020_THRESH_FRACTION; + 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 int hdc3020_power_off(struct hdc3020_data *data) +{ + hdc3020_exec_cmd(data, HDC3020_EXIT_AUTO); + + if (data->reset_gpio) + gpiod_set_value_cansleep(data->reset_gpio, 1); + + return regulator_disable(data->vdd_supply); +} + +static int hdc3020_power_on(struct hdc3020_data *data) +{ + int ret; + + ret = regulator_enable(data->vdd_supply); + if (ret) + return ret; + + fsleep(5000); + + if (data->reset_gpio) { + gpiod_set_value_cansleep(data->reset_gpio, 0); + fsleep(3000); + } + + if (data->client->irq) { + /* + * 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) { + hdc3020_power_off(data); + return ret; + } + } + + ret = hdc3020_exec_cmd(data, HDC3020_S_AUTO_10HZ_MOD0); + if (ret) + hdc3020_power_off(data); + + return ret; +} + +static void hdc3020_exit(void *data) +{ + hdc3020_power_off(data); +} + +static int hdc3020_probe(struct i2c_client *client) +{ + struct iio_dev *indio_dev; + struct hdc3020_data *data; + int ret; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) + return -EOPNOTSUPP; + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); + if (!indio_dev) + return -ENOMEM; + + dev_set_drvdata(&client->dev, indio_dev); + + data = iio_priv(indio_dev); + data->client = client; + mutex_init(&data->lock); + + crc8_populate_msb(hdc3020_crc8_table, HDC3020_CRC8_POLYNOMIAL); + + indio_dev->name = "hdc3020"; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &hdc3020_info; + indio_dev->channels = hdc3020_channels; + indio_dev->num_channels = ARRAY_SIZE(hdc3020_channels); + + data->vdd_supply = devm_regulator_get(&client->dev, "vdd"); + if (IS_ERR(data->vdd_supply)) + return dev_err_probe(&client->dev, PTR_ERR(data->vdd_supply), + "Unable to get VDD regulator\n"); + + data->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset", + GPIOD_OUT_HIGH); + if (IS_ERR(data->reset_gpio)) + return dev_err_probe(&client->dev, PTR_ERR(data->reset_gpio), + "Cannot get reset GPIO\n"); + + ret = hdc3020_power_on(data); + if (ret) + return dev_err_probe(&client->dev, ret, "Power on failed\n"); + + ret = devm_add_action_or_reset(&data->client->dev, hdc3020_exit, data); + if (ret) + return ret; + + 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"); + } + + ret = devm_iio_device_register(&data->client->dev, indio_dev); + if (ret) + return dev_err_probe(&client->dev, ret, "Failed to add device"); + + return 0; +} + +static int hdc3020_suspend(struct device *dev) +{ + struct iio_dev *iio_dev = dev_get_drvdata(dev); + struct hdc3020_data *data = iio_priv(iio_dev); + + return hdc3020_power_off(data); +} + +static int hdc3020_resume(struct device *dev) +{ + struct iio_dev *iio_dev = dev_get_drvdata(dev); + struct hdc3020_data *data = iio_priv(iio_dev); + + return hdc3020_power_on(data); +} + +static DEFINE_SIMPLE_DEV_PM_OPS(hdc3020_pm_ops, hdc3020_suspend, hdc3020_resume); + +static const struct i2c_device_id hdc3020_id[] = { + { "hdc3020" }, + { "hdc3021" }, + { "hdc3022" }, + { } +}; +MODULE_DEVICE_TABLE(i2c, hdc3020_id); + +static const struct of_device_id hdc3020_dt_ids[] = { + { .compatible = "ti,hdc3020" }, + { .compatible = "ti,hdc3021" }, + { .compatible = "ti,hdc3022" }, + { } +}; +MODULE_DEVICE_TABLE(of, hdc3020_dt_ids); + +static struct i2c_driver hdc3020_driver = { + .driver = { + .name = "hdc3020", + .pm = pm_sleep_ptr(&hdc3020_pm_ops), + .of_match_table = hdc3020_dt_ids, + }, + .probe = hdc3020_probe, + .id_table = hdc3020_id, +}; +module_i2c_driver(hdc3020_driver); + +MODULE_AUTHOR("Javier Carrasco <javier.carrasco.cruz@gmail.com>"); +MODULE_AUTHOR("Li peiyu <579lpy@gmail.com>"); +MODULE_DESCRIPTION("TI HDC3020 humidity and temperature sensor driver"); +MODULE_LICENSE("GPL"); |