summaryrefslogtreecommitdiffstats
path: root/drivers/iio/light/veml6030.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/iio/light/veml6030.c')
-rw-r--r--drivers/iio/light/veml6030.c907
1 files changed, 907 insertions, 0 deletions
diff --git a/drivers/iio/light/veml6030.c b/drivers/iio/light/veml6030.c
new file mode 100644
index 000000000..de85c9b30
--- /dev/null
+++ b/drivers/iio/light/veml6030.c
@@ -0,0 +1,907 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * VEML6030 Ambient Light Sensor
+ *
+ * Copyright (c) 2019, Rishi Gupta <gupt21@gmail.com>
+ *
+ * Datasheet: https://www.vishay.com/docs/84366/veml6030.pdf
+ * Appnote-84367: https://www.vishay.com/docs/84367/designingveml6030.pdf
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/regmap.h>
+#include <linux/interrupt.h>
+#include <linux/pm_runtime.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/events.h>
+
+/* Device registers */
+#define VEML6030_REG_ALS_CONF 0x00
+#define VEML6030_REG_ALS_WH 0x01
+#define VEML6030_REG_ALS_WL 0x02
+#define VEML6030_REG_ALS_PSM 0x03
+#define VEML6030_REG_ALS_DATA 0x04
+#define VEML6030_REG_WH_DATA 0x05
+#define VEML6030_REG_ALS_INT 0x06
+
+/* Bit masks for specific functionality */
+#define VEML6030_ALS_IT GENMASK(9, 6)
+#define VEML6030_PSM GENMASK(2, 1)
+#define VEML6030_ALS_PERS GENMASK(5, 4)
+#define VEML6030_ALS_GAIN GENMASK(12, 11)
+#define VEML6030_PSM_EN BIT(0)
+#define VEML6030_INT_TH_LOW BIT(15)
+#define VEML6030_INT_TH_HIGH BIT(14)
+#define VEML6030_ALS_INT_EN BIT(1)
+#define VEML6030_ALS_SD BIT(0)
+
+/*
+ * The resolution depends on both gain and integration time. The
+ * cur_resolution stores one of the resolution mentioned in the
+ * table during startup and gets updated whenever integration time
+ * or gain is changed.
+ *
+ * Table 'resolution and maximum detection range' in appnote 84367
+ * is visualized as a 2D array. The cur_gain stores index of gain
+ * in this table (0-3) while the cur_integration_time holds index
+ * of integration time (0-5).
+ */
+struct veml6030_data {
+ struct i2c_client *client;
+ struct regmap *regmap;
+ int cur_resolution;
+ int cur_gain;
+ int cur_integration_time;
+};
+
+/* Integration time available in seconds */
+static IIO_CONST_ATTR(in_illuminance_integration_time_available,
+ "0.025 0.05 0.1 0.2 0.4 0.8");
+
+/*
+ * Scale is 1/gain. Value 0.125 is ALS gain x (1/8), 0.25 is
+ * ALS gain x (1/4), 1.0 = ALS gain x 1 and 2.0 is ALS gain x 2.
+ */
+static IIO_CONST_ATTR(in_illuminance_scale_available,
+ "0.125 0.25 1.0 2.0");
+
+static struct attribute *veml6030_attributes[] = {
+ &iio_const_attr_in_illuminance_integration_time_available.dev_attr.attr,
+ &iio_const_attr_in_illuminance_scale_available.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group veml6030_attr_group = {
+ .attrs = veml6030_attributes,
+};
+
+/*
+ * Persistence = 1/2/4/8 x integration time
+ * Minimum time for which light readings must stay above configured
+ * threshold to assert the interrupt.
+ */
+static const char * const period_values[] = {
+ "0.1 0.2 0.4 0.8",
+ "0.2 0.4 0.8 1.6",
+ "0.4 0.8 1.6 3.2",
+ "0.8 1.6 3.2 6.4",
+ "0.05 0.1 0.2 0.4",
+ "0.025 0.050 0.1 0.2"
+};
+
+/*
+ * Return list of valid period values in seconds corresponding to
+ * the currently active integration time.
+ */
+static ssize_t in_illuminance_period_available_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int ret, reg, x;
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct veml6030_data *data = iio_priv(indio_dev);
+
+ ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, &reg);
+ if (ret) {
+ dev_err(&data->client->dev,
+ "can't read als conf register %d\n", ret);
+ return ret;
+ }
+
+ ret = ((reg >> 6) & 0xF);
+ switch (ret) {
+ case 0:
+ case 1:
+ case 2:
+ case 3:
+ x = ret;
+ break;
+ case 8:
+ x = 4;
+ break;
+ case 12:
+ x = 5;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return snprintf(buf, PAGE_SIZE, "%s\n", period_values[x]);
+}
+
+static IIO_DEVICE_ATTR_RO(in_illuminance_period_available, 0);
+
+static struct attribute *veml6030_event_attributes[] = {
+ &iio_dev_attr_in_illuminance_period_available.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group veml6030_event_attr_group = {
+ .attrs = veml6030_event_attributes,
+};
+
+static int veml6030_als_pwr_on(struct veml6030_data *data)
+{
+ return regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF,
+ VEML6030_ALS_SD, 0);
+}
+
+static int veml6030_als_shut_down(struct veml6030_data *data)
+{
+ return regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF,
+ VEML6030_ALS_SD, 1);
+}
+
+static void veml6030_als_shut_down_action(void *data)
+{
+ veml6030_als_shut_down(data);
+}
+
+static const struct iio_event_spec veml6030_event_spec[] = {
+ {
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_RISING,
+ .mask_separate = BIT(IIO_EV_INFO_VALUE),
+ }, {
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_FALLING,
+ .mask_separate = BIT(IIO_EV_INFO_VALUE),
+ }, {
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_EITHER,
+ .mask_separate = BIT(IIO_EV_INFO_PERIOD) |
+ BIT(IIO_EV_INFO_ENABLE),
+ },
+};
+
+/* Channel number */
+enum veml6030_chan {
+ CH_ALS,
+ CH_WHITE,
+};
+
+static const struct iio_chan_spec veml6030_channels[] = {
+ {
+ .type = IIO_LIGHT,
+ .channel = CH_ALS,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_PROCESSED) |
+ BIT(IIO_CHAN_INFO_INT_TIME) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ .event_spec = veml6030_event_spec,
+ .num_event_specs = ARRAY_SIZE(veml6030_event_spec),
+ },
+ {
+ .type = IIO_INTENSITY,
+ .channel = CH_WHITE,
+ .modified = 1,
+ .channel2 = IIO_MOD_LIGHT_BOTH,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_PROCESSED),
+ },
+};
+
+static const struct regmap_config veml6030_regmap_config = {
+ .name = "veml6030_regmap",
+ .reg_bits = 8,
+ .val_bits = 16,
+ .max_register = VEML6030_REG_ALS_INT,
+ .val_format_endian = REGMAP_ENDIAN_LITTLE,
+};
+
+static int veml6030_get_intgrn_tm(struct iio_dev *indio_dev,
+ int *val, int *val2)
+{
+ int ret, reg;
+ struct veml6030_data *data = iio_priv(indio_dev);
+
+ ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, &reg);
+ if (ret) {
+ dev_err(&data->client->dev,
+ "can't read als conf register %d\n", ret);
+ return ret;
+ }
+
+ switch ((reg >> 6) & 0xF) {
+ case 0:
+ *val2 = 100000;
+ break;
+ case 1:
+ *val2 = 200000;
+ break;
+ case 2:
+ *val2 = 400000;
+ break;
+ case 3:
+ *val2 = 800000;
+ break;
+ case 8:
+ *val2 = 50000;
+ break;
+ case 12:
+ *val2 = 25000;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ *val = 0;
+ return IIO_VAL_INT_PLUS_MICRO;
+}
+
+static int veml6030_set_intgrn_tm(struct iio_dev *indio_dev,
+ int val, int val2)
+{
+ int ret, new_int_time, int_idx;
+ struct veml6030_data *data = iio_priv(indio_dev);
+
+ if (val)
+ return -EINVAL;
+
+ switch (val2) {
+ case 25000:
+ new_int_time = 0x300;
+ int_idx = 5;
+ break;
+ case 50000:
+ new_int_time = 0x200;
+ int_idx = 4;
+ break;
+ case 100000:
+ new_int_time = 0x00;
+ int_idx = 3;
+ break;
+ case 200000:
+ new_int_time = 0x40;
+ int_idx = 2;
+ break;
+ case 400000:
+ new_int_time = 0x80;
+ int_idx = 1;
+ break;
+ case 800000:
+ new_int_time = 0xC0;
+ int_idx = 0;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF,
+ VEML6030_ALS_IT, new_int_time);
+ if (ret) {
+ dev_err(&data->client->dev,
+ "can't update als integration time %d\n", ret);
+ return ret;
+ }
+
+ /*
+ * Cache current integration time and update resolution. For every
+ * increase in integration time to next level, resolution is halved
+ * and vice-versa.
+ */
+ if (data->cur_integration_time < int_idx)
+ data->cur_resolution <<= int_idx - data->cur_integration_time;
+ else if (data->cur_integration_time > int_idx)
+ data->cur_resolution >>= data->cur_integration_time - int_idx;
+
+ data->cur_integration_time = int_idx;
+
+ return ret;
+}
+
+static int veml6030_read_persistence(struct iio_dev *indio_dev,
+ int *val, int *val2)
+{
+ int ret, reg, period, x, y;
+ struct veml6030_data *data = iio_priv(indio_dev);
+
+ ret = veml6030_get_intgrn_tm(indio_dev, &x, &y);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, &reg);
+ if (ret) {
+ dev_err(&data->client->dev,
+ "can't read als conf register %d\n", ret);
+ }
+
+ /* integration time multiplied by 1/2/4/8 */
+ period = y * (1 << ((reg >> 4) & 0x03));
+
+ *val = period / 1000000;
+ *val2 = period % 1000000;
+
+ return IIO_VAL_INT_PLUS_MICRO;
+}
+
+static int veml6030_write_persistence(struct iio_dev *indio_dev,
+ int val, int val2)
+{
+ int ret, period, x, y;
+ struct veml6030_data *data = iio_priv(indio_dev);
+
+ ret = veml6030_get_intgrn_tm(indio_dev, &x, &y);
+ if (ret < 0)
+ return ret;
+
+ if (!val) {
+ period = val2 / y;
+ } else {
+ if ((val == 1) && (val2 == 600000))
+ period = 1600000 / y;
+ else if ((val == 3) && (val2 == 200000))
+ period = 3200000 / y;
+ else if ((val == 6) && (val2 == 400000))
+ period = 6400000 / y;
+ else
+ period = -1;
+ }
+
+ if (period <= 0 || period > 8 || hweight8(period) != 1)
+ return -EINVAL;
+
+ ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF,
+ VEML6030_ALS_PERS, (ffs(period) - 1) << 4);
+ if (ret)
+ dev_err(&data->client->dev,
+ "can't set persistence value %d\n", ret);
+
+ return ret;
+}
+
+static int veml6030_set_als_gain(struct iio_dev *indio_dev,
+ int val, int val2)
+{
+ int ret, new_gain, gain_idx;
+ struct veml6030_data *data = iio_priv(indio_dev);
+
+ if (val == 0 && val2 == 125000) {
+ new_gain = 0x1000; /* 0x02 << 11 */
+ gain_idx = 3;
+ } else if (val == 0 && val2 == 250000) {
+ new_gain = 0x1800;
+ gain_idx = 2;
+ } else if (val == 1 && val2 == 0) {
+ new_gain = 0x00;
+ gain_idx = 1;
+ } else if (val == 2 && val2 == 0) {
+ new_gain = 0x800;
+ gain_idx = 0;
+ } else {
+ return -EINVAL;
+ }
+
+ ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF,
+ VEML6030_ALS_GAIN, new_gain);
+ if (ret) {
+ dev_err(&data->client->dev,
+ "can't set als gain %d\n", ret);
+ return ret;
+ }
+
+ /*
+ * Cache currently set gain & update resolution. For every
+ * increase in the gain to next level, resolution is halved
+ * and vice-versa.
+ */
+ if (data->cur_gain < gain_idx)
+ data->cur_resolution <<= gain_idx - data->cur_gain;
+ else if (data->cur_gain > gain_idx)
+ data->cur_resolution >>= data->cur_gain - gain_idx;
+
+ data->cur_gain = gain_idx;
+
+ return ret;
+}
+
+static int veml6030_get_als_gain(struct iio_dev *indio_dev,
+ int *val, int *val2)
+{
+ int ret, reg;
+ struct veml6030_data *data = iio_priv(indio_dev);
+
+ ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, &reg);
+ if (ret) {
+ dev_err(&data->client->dev,
+ "can't read als conf register %d\n", ret);
+ return ret;
+ }
+
+ switch ((reg >> 11) & 0x03) {
+ case 0:
+ *val = 1;
+ *val2 = 0;
+ break;
+ case 1:
+ *val = 2;
+ *val2 = 0;
+ break;
+ case 2:
+ *val = 0;
+ *val2 = 125000;
+ break;
+ case 3:
+ *val = 0;
+ *val2 = 250000;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return IIO_VAL_INT_PLUS_MICRO;
+}
+
+static int veml6030_read_thresh(struct iio_dev *indio_dev,
+ int *val, int *val2, int dir)
+{
+ int ret, reg;
+ struct veml6030_data *data = iio_priv(indio_dev);
+
+ if (dir == IIO_EV_DIR_RISING)
+ ret = regmap_read(data->regmap, VEML6030_REG_ALS_WH, &reg);
+ else
+ ret = regmap_read(data->regmap, VEML6030_REG_ALS_WL, &reg);
+ if (ret) {
+ dev_err(&data->client->dev,
+ "can't read als threshold value %d\n", ret);
+ return ret;
+ }
+
+ *val = reg & 0xffff;
+ return IIO_VAL_INT;
+}
+
+static int veml6030_write_thresh(struct iio_dev *indio_dev,
+ int val, int val2, int dir)
+{
+ int ret;
+ struct veml6030_data *data = iio_priv(indio_dev);
+
+ if (val > 0xFFFF || val < 0 || val2)
+ return -EINVAL;
+
+ if (dir == IIO_EV_DIR_RISING) {
+ ret = regmap_write(data->regmap, VEML6030_REG_ALS_WH, val);
+ if (ret)
+ dev_err(&data->client->dev,
+ "can't set high threshold %d\n", ret);
+ } else {
+ ret = regmap_write(data->regmap, VEML6030_REG_ALS_WL, val);
+ if (ret)
+ dev_err(&data->client->dev,
+ "can't set low threshold %d\n", ret);
+ }
+
+ return ret;
+}
+
+/*
+ * Provide both raw as well as light reading in lux.
+ * light (in lux) = resolution * raw reading
+ */
+static int veml6030_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int *val,
+ int *val2, long mask)
+{
+ int ret, reg;
+ struct veml6030_data *data = iio_priv(indio_dev);
+ struct regmap *regmap = data->regmap;
+ struct device *dev = &data->client->dev;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ case IIO_CHAN_INFO_PROCESSED:
+ switch (chan->type) {
+ case IIO_LIGHT:
+ ret = regmap_read(regmap, VEML6030_REG_ALS_DATA, &reg);
+ if (ret < 0) {
+ dev_err(dev, "can't read als data %d\n", ret);
+ return ret;
+ }
+ if (mask == IIO_CHAN_INFO_PROCESSED) {
+ *val = (reg * data->cur_resolution) / 10000;
+ *val2 = (reg * data->cur_resolution) % 10000;
+ return IIO_VAL_INT_PLUS_MICRO;
+ }
+ *val = reg;
+ return IIO_VAL_INT;
+ case IIO_INTENSITY:
+ ret = regmap_read(regmap, VEML6030_REG_WH_DATA, &reg);
+ if (ret < 0) {
+ dev_err(dev, "can't read white data %d\n", ret);
+ return ret;
+ }
+ if (mask == IIO_CHAN_INFO_PROCESSED) {
+ *val = (reg * data->cur_resolution) / 10000;
+ *val2 = (reg * data->cur_resolution) % 10000;
+ return IIO_VAL_INT_PLUS_MICRO;
+ }
+ *val = reg;
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_INT_TIME:
+ if (chan->type == IIO_LIGHT)
+ return veml6030_get_intgrn_tm(indio_dev, val, val2);
+ return -EINVAL;
+ case IIO_CHAN_INFO_SCALE:
+ if (chan->type == IIO_LIGHT)
+ return veml6030_get_als_gain(indio_dev, val, val2);
+ return -EINVAL;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int veml6030_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ switch (mask) {
+ case IIO_CHAN_INFO_INT_TIME:
+ switch (chan->type) {
+ case IIO_LIGHT:
+ return veml6030_set_intgrn_tm(indio_dev, val, val2);
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->type) {
+ case IIO_LIGHT:
+ return veml6030_set_als_gain(indio_dev, val, val2);
+ default:
+ return -EINVAL;
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+static int veml6030_read_event_val(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)
+{
+ switch (info) {
+ case IIO_EV_INFO_VALUE:
+ switch (dir) {
+ case IIO_EV_DIR_RISING:
+ case IIO_EV_DIR_FALLING:
+ return veml6030_read_thresh(indio_dev, val, val2, dir);
+ default:
+ return -EINVAL;
+ }
+ break;
+ case IIO_EV_INFO_PERIOD:
+ return veml6030_read_persistence(indio_dev, val, val2);
+ default:
+ return -EINVAL;
+ }
+}
+
+static int veml6030_write_event_val(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)
+{
+ switch (info) {
+ case IIO_EV_INFO_VALUE:
+ return veml6030_write_thresh(indio_dev, val, val2, dir);
+ case IIO_EV_INFO_PERIOD:
+ return veml6030_write_persistence(indio_dev, val, val2);
+ default:
+ return -EINVAL;
+ }
+}
+
+static int veml6030_read_interrupt_config(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan, enum iio_event_type type,
+ enum iio_event_direction dir)
+{
+ int ret, reg;
+ struct veml6030_data *data = iio_priv(indio_dev);
+
+ ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, &reg);
+ if (ret) {
+ dev_err(&data->client->dev,
+ "can't read als conf register %d\n", ret);
+ return ret;
+ }
+
+ if (reg & VEML6030_ALS_INT_EN)
+ return 1;
+ else
+ return 0;
+}
+
+/*
+ * Sensor should not be measuring light when interrupt is configured.
+ * Therefore correct sequence to configure interrupt functionality is:
+ * shut down -> enable/disable interrupt -> power on
+ *
+ * state = 1 enables interrupt, state = 0 disables interrupt
+ */
+static int veml6030_write_interrupt_config(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan, enum iio_event_type type,
+ enum iio_event_direction dir, int state)
+{
+ int ret;
+ struct veml6030_data *data = iio_priv(indio_dev);
+
+ if (state < 0 || state > 1)
+ return -EINVAL;
+
+ ret = veml6030_als_shut_down(data);
+ if (ret < 0) {
+ dev_err(&data->client->dev,
+ "can't disable als to configure interrupt %d\n", ret);
+ return ret;
+ }
+
+ /* enable interrupt + power on */
+ ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF,
+ VEML6030_ALS_INT_EN | VEML6030_ALS_SD, state << 1);
+ if (ret)
+ dev_err(&data->client->dev,
+ "can't enable interrupt & poweron als %d\n", ret);
+
+ return ret;
+}
+
+static const struct iio_info veml6030_info = {
+ .read_raw = veml6030_read_raw,
+ .write_raw = veml6030_write_raw,
+ .read_event_value = veml6030_read_event_val,
+ .write_event_value = veml6030_write_event_val,
+ .read_event_config = veml6030_read_interrupt_config,
+ .write_event_config = veml6030_write_interrupt_config,
+ .attrs = &veml6030_attr_group,
+ .event_attrs = &veml6030_event_attr_group,
+};
+
+static const struct iio_info veml6030_info_no_irq = {
+ .read_raw = veml6030_read_raw,
+ .write_raw = veml6030_write_raw,
+ .attrs = &veml6030_attr_group,
+};
+
+static irqreturn_t veml6030_event_handler(int irq, void *private)
+{
+ int ret, reg, evtdir;
+ struct iio_dev *indio_dev = private;
+ struct veml6030_data *data = iio_priv(indio_dev);
+
+ ret = regmap_read(data->regmap, VEML6030_REG_ALS_INT, &reg);
+ if (ret) {
+ dev_err(&data->client->dev,
+ "can't read als interrupt register %d\n", ret);
+ return IRQ_HANDLED;
+ }
+
+ /* Spurious interrupt handling */
+ if (!(reg & (VEML6030_INT_TH_HIGH | VEML6030_INT_TH_LOW)))
+ return IRQ_NONE;
+
+ if (reg & VEML6030_INT_TH_HIGH)
+ evtdir = IIO_EV_DIR_RISING;
+ else
+ evtdir = IIO_EV_DIR_FALLING;
+
+ iio_push_event(indio_dev, IIO_UNMOD_EVENT_CODE(IIO_INTENSITY,
+ 0, IIO_EV_TYPE_THRESH, evtdir),
+ iio_get_time_ns(indio_dev));
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * Set ALS gain to 1/8, integration time to 100 ms, PSM to mode 2,
+ * persistence to 1 x integration time and the threshold
+ * interrupt disabled by default. First shutdown the sensor,
+ * update registers and then power on the sensor.
+ */
+static int veml6030_hw_init(struct iio_dev *indio_dev)
+{
+ int ret, val;
+ struct veml6030_data *data = iio_priv(indio_dev);
+ struct i2c_client *client = data->client;
+
+ ret = veml6030_als_shut_down(data);
+ if (ret) {
+ dev_err(&client->dev, "can't shutdown als %d\n", ret);
+ return ret;
+ }
+
+ ret = regmap_write(data->regmap, VEML6030_REG_ALS_CONF, 0x1001);
+ if (ret) {
+ dev_err(&client->dev, "can't setup als configs %d\n", ret);
+ return ret;
+ }
+
+ ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_PSM,
+ VEML6030_PSM | VEML6030_PSM_EN, 0x03);
+ if (ret) {
+ dev_err(&client->dev, "can't setup default PSM %d\n", ret);
+ return ret;
+ }
+
+ ret = regmap_write(data->regmap, VEML6030_REG_ALS_WH, 0xFFFF);
+ if (ret) {
+ dev_err(&client->dev, "can't setup high threshold %d\n", ret);
+ return ret;
+ }
+
+ ret = regmap_write(data->regmap, VEML6030_REG_ALS_WL, 0x0000);
+ if (ret) {
+ dev_err(&client->dev, "can't setup low threshold %d\n", ret);
+ return ret;
+ }
+
+ ret = veml6030_als_pwr_on(data);
+ if (ret) {
+ dev_err(&client->dev, "can't poweron als %d\n", ret);
+ return ret;
+ }
+
+ /* Wait 4 ms to let processor & oscillator start correctly */
+ usleep_range(4000, 4002);
+
+ /* Clear stale interrupt status bits if any during start */
+ ret = regmap_read(data->regmap, VEML6030_REG_ALS_INT, &val);
+ if (ret < 0) {
+ dev_err(&client->dev,
+ "can't clear als interrupt status %d\n", ret);
+ return ret;
+ }
+
+ /* Cache currently active measurement parameters */
+ data->cur_gain = 3;
+ data->cur_resolution = 4608;
+ data->cur_integration_time = 3;
+
+ return ret;
+}
+
+static int veml6030_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ int ret;
+ struct veml6030_data *data;
+ struct iio_dev *indio_dev;
+ struct regmap *regmap;
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+ dev_err(&client->dev, "i2c adapter doesn't support plain i2c\n");
+ return -EOPNOTSUPP;
+ }
+
+ regmap = devm_regmap_init_i2c(client, &veml6030_regmap_config);
+ if (IS_ERR(regmap)) {
+ dev_err(&client->dev, "can't setup regmap\n");
+ return PTR_ERR(regmap);
+ }
+
+ indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ data = iio_priv(indio_dev);
+ i2c_set_clientdata(client, indio_dev);
+ data->client = client;
+ data->regmap = regmap;
+
+ indio_dev->name = "veml6030";
+ indio_dev->channels = veml6030_channels;
+ indio_dev->num_channels = ARRAY_SIZE(veml6030_channels);
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ if (client->irq) {
+ ret = devm_request_threaded_irq(&client->dev, client->irq,
+ NULL, veml6030_event_handler,
+ IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+ "veml6030", indio_dev);
+ if (ret < 0) {
+ dev_err(&client->dev,
+ "irq %d request failed\n", client->irq);
+ return ret;
+ }
+ indio_dev->info = &veml6030_info;
+ } else {
+ indio_dev->info = &veml6030_info_no_irq;
+ }
+
+ ret = veml6030_hw_init(indio_dev);
+ if (ret < 0)
+ return ret;
+
+ ret = devm_add_action_or_reset(&client->dev,
+ veml6030_als_shut_down_action, data);
+ if (ret < 0)
+ return ret;
+
+ return devm_iio_device_register(&client->dev, indio_dev);
+}
+
+static int __maybe_unused veml6030_runtime_suspend(struct device *dev)
+{
+ int ret;
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct veml6030_data *data = iio_priv(indio_dev);
+
+ ret = veml6030_als_shut_down(data);
+ if (ret < 0)
+ dev_err(&data->client->dev, "can't suspend als %d\n", ret);
+
+ return ret;
+}
+
+static int __maybe_unused veml6030_runtime_resume(struct device *dev)
+{
+ int ret;
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct veml6030_data *data = iio_priv(indio_dev);
+
+ ret = veml6030_als_pwr_on(data);
+ if (ret < 0)
+ dev_err(&data->client->dev, "can't resume als %d\n", ret);
+
+ return ret;
+}
+
+static const struct dev_pm_ops veml6030_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SET_RUNTIME_PM_OPS(veml6030_runtime_suspend,
+ veml6030_runtime_resume, NULL)
+};
+
+static const struct of_device_id veml6030_of_match[] = {
+ { .compatible = "vishay,veml6030" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, veml6030_of_match);
+
+static const struct i2c_device_id veml6030_id[] = {
+ { "veml6030", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, veml6030_id);
+
+static struct i2c_driver veml6030_driver = {
+ .driver = {
+ .name = "veml6030",
+ .of_match_table = veml6030_of_match,
+ .pm = &veml6030_pm_ops,
+ },
+ .probe = veml6030_probe,
+ .id_table = veml6030_id,
+};
+module_i2c_driver(veml6030_driver);
+
+MODULE_AUTHOR("Rishi Gupta <gupt21@gmail.com>");
+MODULE_DESCRIPTION("VEML6030 Ambient Light Sensor");
+MODULE_LICENSE("GPL v2");