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-rw-r--r--drivers/iio/light/isl29028.c716
1 files changed, 716 insertions, 0 deletions
diff --git a/drivers/iio/light/isl29028.c b/drivers/iio/light/isl29028.c
new file mode 100644
index 000000000..74e754776
--- /dev/null
+++ b/drivers/iio/light/isl29028.c
@@ -0,0 +1,716 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * IIO driver for the light sensor ISL29028.
+ * ISL29028 is Concurrent Ambient Light and Proximity Sensor
+ *
+ * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
+ * Copyright (c) 2016-2017 Brian Masney <masneyb@onstation.org>
+ *
+ * Datasheets:
+ * - http://www.intersil.com/content/dam/Intersil/documents/isl2/isl29028.pdf
+ * - http://www.intersil.com/content/dam/Intersil/documents/isl2/isl29030.pdf
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/regmap.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/pm_runtime.h>
+
+#define ISL29028_CONV_TIME_MS 100
+
+#define ISL29028_REG_CONFIGURE 0x01
+
+#define ISL29028_CONF_ALS_IR_MODE_ALS 0
+#define ISL29028_CONF_ALS_IR_MODE_IR BIT(0)
+#define ISL29028_CONF_ALS_IR_MODE_MASK BIT(0)
+
+#define ISL29028_CONF_ALS_RANGE_LOW_LUX 0
+#define ISL29028_CONF_ALS_RANGE_HIGH_LUX BIT(1)
+#define ISL29028_CONF_ALS_RANGE_MASK BIT(1)
+
+#define ISL29028_CONF_ALS_DIS 0
+#define ISL29028_CONF_ALS_EN BIT(2)
+#define ISL29028_CONF_ALS_EN_MASK BIT(2)
+
+#define ISL29028_CONF_PROX_SLP_SH 4
+#define ISL29028_CONF_PROX_SLP_MASK (7 << ISL29028_CONF_PROX_SLP_SH)
+
+#define ISL29028_CONF_PROX_EN BIT(7)
+#define ISL29028_CONF_PROX_EN_MASK BIT(7)
+
+#define ISL29028_REG_INTERRUPT 0x02
+
+#define ISL29028_REG_PROX_DATA 0x08
+#define ISL29028_REG_ALSIR_L 0x09
+#define ISL29028_REG_ALSIR_U 0x0A
+
+#define ISL29028_REG_TEST1_MODE 0x0E
+#define ISL29028_REG_TEST2_MODE 0x0F
+
+#define ISL29028_NUM_REGS (ISL29028_REG_TEST2_MODE + 1)
+
+#define ISL29028_POWER_OFF_DELAY_MS 2000
+
+struct isl29028_prox_data {
+ int sampling_int;
+ int sampling_fract;
+ int sleep_time;
+};
+
+static const struct isl29028_prox_data isl29028_prox_data[] = {
+ { 1, 250000, 800 },
+ { 2, 500000, 400 },
+ { 5, 0, 200 },
+ { 10, 0, 100 },
+ { 13, 300000, 75 },
+ { 20, 0, 50 },
+ { 80, 0, 13 }, /*
+ * Note: Data sheet lists 12.5 ms sleep time.
+ * Round up a half millisecond for msleep().
+ */
+ { 100, 0, 0 }
+};
+
+enum isl29028_als_ir_mode {
+ ISL29028_MODE_NONE = 0,
+ ISL29028_MODE_ALS,
+ ISL29028_MODE_IR,
+};
+
+struct isl29028_chip {
+ struct mutex lock;
+ struct regmap *regmap;
+ int prox_sampling_int;
+ int prox_sampling_frac;
+ bool enable_prox;
+ int lux_scale;
+ enum isl29028_als_ir_mode als_ir_mode;
+};
+
+static int isl29028_find_prox_sleep_index(int sampling_int, int sampling_fract)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(isl29028_prox_data); ++i) {
+ if (isl29028_prox_data[i].sampling_int == sampling_int &&
+ isl29028_prox_data[i].sampling_fract == sampling_fract)
+ return i;
+ }
+
+ return -EINVAL;
+}
+
+static int isl29028_set_proxim_sampling(struct isl29028_chip *chip,
+ int sampling_int, int sampling_fract)
+{
+ struct device *dev = regmap_get_device(chip->regmap);
+ int sleep_index, ret;
+
+ sleep_index = isl29028_find_prox_sleep_index(sampling_int,
+ sampling_fract);
+ if (sleep_index < 0)
+ return sleep_index;
+
+ ret = regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
+ ISL29028_CONF_PROX_SLP_MASK,
+ sleep_index << ISL29028_CONF_PROX_SLP_SH);
+
+ if (ret < 0) {
+ dev_err(dev, "%s(): Error %d setting the proximity sampling\n",
+ __func__, ret);
+ return ret;
+ }
+
+ chip->prox_sampling_int = sampling_int;
+ chip->prox_sampling_frac = sampling_fract;
+
+ return ret;
+}
+
+static int isl29028_enable_proximity(struct isl29028_chip *chip)
+{
+ int prox_index, ret;
+
+ ret = isl29028_set_proxim_sampling(chip, chip->prox_sampling_int,
+ chip->prox_sampling_frac);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
+ ISL29028_CONF_PROX_EN_MASK,
+ ISL29028_CONF_PROX_EN);
+ if (ret < 0)
+ return ret;
+
+ /* Wait for conversion to be complete for first sample */
+ prox_index = isl29028_find_prox_sleep_index(chip->prox_sampling_int,
+ chip->prox_sampling_frac);
+ if (prox_index < 0)
+ return prox_index;
+
+ msleep(isl29028_prox_data[prox_index].sleep_time);
+
+ return 0;
+}
+
+static int isl29028_set_als_scale(struct isl29028_chip *chip, int lux_scale)
+{
+ struct device *dev = regmap_get_device(chip->regmap);
+ int val = (lux_scale == 2000) ? ISL29028_CONF_ALS_RANGE_HIGH_LUX :
+ ISL29028_CONF_ALS_RANGE_LOW_LUX;
+ int ret;
+
+ ret = regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
+ ISL29028_CONF_ALS_RANGE_MASK, val);
+ if (ret < 0) {
+ dev_err(dev, "%s(): Error %d setting the ALS scale\n", __func__,
+ ret);
+ return ret;
+ }
+
+ chip->lux_scale = lux_scale;
+
+ return ret;
+}
+
+static int isl29028_set_als_ir_mode(struct isl29028_chip *chip,
+ enum isl29028_als_ir_mode mode)
+{
+ int ret;
+
+ if (chip->als_ir_mode == mode)
+ return 0;
+
+ ret = isl29028_set_als_scale(chip, chip->lux_scale);
+ if (ret < 0)
+ return ret;
+
+ switch (mode) {
+ case ISL29028_MODE_ALS:
+ ret = regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
+ ISL29028_CONF_ALS_IR_MODE_MASK,
+ ISL29028_CONF_ALS_IR_MODE_ALS);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
+ ISL29028_CONF_ALS_RANGE_MASK,
+ ISL29028_CONF_ALS_RANGE_HIGH_LUX);
+ break;
+ case ISL29028_MODE_IR:
+ ret = regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
+ ISL29028_CONF_ALS_IR_MODE_MASK,
+ ISL29028_CONF_ALS_IR_MODE_IR);
+ break;
+ case ISL29028_MODE_NONE:
+ return regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
+ ISL29028_CONF_ALS_EN_MASK,
+ ISL29028_CONF_ALS_DIS);
+ }
+
+ if (ret < 0)
+ return ret;
+
+ /* Enable the ALS/IR */
+ ret = regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
+ ISL29028_CONF_ALS_EN_MASK,
+ ISL29028_CONF_ALS_EN);
+ if (ret < 0)
+ return ret;
+
+ /* Need to wait for conversion time if ALS/IR mode enabled */
+ msleep(ISL29028_CONV_TIME_MS);
+
+ chip->als_ir_mode = mode;
+
+ return 0;
+}
+
+static int isl29028_read_als_ir(struct isl29028_chip *chip, int *als_ir)
+{
+ struct device *dev = regmap_get_device(chip->regmap);
+ unsigned int lsb;
+ unsigned int msb;
+ int ret;
+
+ ret = regmap_read(chip->regmap, ISL29028_REG_ALSIR_L, &lsb);
+ if (ret < 0) {
+ dev_err(dev,
+ "%s(): Error %d reading register ALSIR_L\n",
+ __func__, ret);
+ return ret;
+ }
+
+ ret = regmap_read(chip->regmap, ISL29028_REG_ALSIR_U, &msb);
+ if (ret < 0) {
+ dev_err(dev,
+ "%s(): Error %d reading register ALSIR_U\n",
+ __func__, ret);
+ return ret;
+ }
+
+ *als_ir = ((msb & 0xF) << 8) | (lsb & 0xFF);
+
+ return 0;
+}
+
+static int isl29028_read_proxim(struct isl29028_chip *chip, int *prox)
+{
+ struct device *dev = regmap_get_device(chip->regmap);
+ unsigned int data;
+ int ret;
+
+ if (!chip->enable_prox) {
+ ret = isl29028_enable_proximity(chip);
+ if (ret < 0)
+ return ret;
+
+ chip->enable_prox = true;
+ }
+
+ ret = regmap_read(chip->regmap, ISL29028_REG_PROX_DATA, &data);
+ if (ret < 0) {
+ dev_err(dev, "%s(): Error %d reading register PROX_DATA\n",
+ __func__, ret);
+ return ret;
+ }
+
+ *prox = data;
+
+ return 0;
+}
+
+static int isl29028_als_get(struct isl29028_chip *chip, int *als_data)
+{
+ struct device *dev = regmap_get_device(chip->regmap);
+ int ret;
+ int als_ir_data;
+
+ ret = isl29028_set_als_ir_mode(chip, ISL29028_MODE_ALS);
+ if (ret < 0) {
+ dev_err(dev, "%s(): Error %d enabling ALS mode\n", __func__,
+ ret);
+ return ret;
+ }
+
+ ret = isl29028_read_als_ir(chip, &als_ir_data);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * convert als data count to lux.
+ * if lux_scale = 125, lux = count * 0.031
+ * if lux_scale = 2000, lux = count * 0.49
+ */
+ if (chip->lux_scale == 125)
+ als_ir_data = (als_ir_data * 31) / 1000;
+ else
+ als_ir_data = (als_ir_data * 49) / 100;
+
+ *als_data = als_ir_data;
+
+ return 0;
+}
+
+static int isl29028_ir_get(struct isl29028_chip *chip, int *ir_data)
+{
+ struct device *dev = regmap_get_device(chip->regmap);
+ int ret;
+
+ ret = isl29028_set_als_ir_mode(chip, ISL29028_MODE_IR);
+ if (ret < 0) {
+ dev_err(dev, "%s(): Error %d enabling IR mode\n", __func__,
+ ret);
+ return ret;
+ }
+
+ return isl29028_read_als_ir(chip, ir_data);
+}
+
+static int isl29028_set_pm_runtime_busy(struct isl29028_chip *chip, bool on)
+{
+ struct device *dev = regmap_get_device(chip->regmap);
+ int ret;
+
+ if (on) {
+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0)
+ pm_runtime_put_noidle(dev);
+ } else {
+ pm_runtime_mark_last_busy(dev);
+ ret = pm_runtime_put_autosuspend(dev);
+ }
+
+ return ret;
+}
+
+/* Channel IO */
+static int isl29028_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct isl29028_chip *chip = iio_priv(indio_dev);
+ struct device *dev = regmap_get_device(chip->regmap);
+ int ret;
+
+ ret = isl29028_set_pm_runtime_busy(chip, true);
+ if (ret < 0)
+ return ret;
+
+ mutex_lock(&chip->lock);
+
+ ret = -EINVAL;
+ switch (chan->type) {
+ case IIO_PROXIMITY:
+ if (mask != IIO_CHAN_INFO_SAMP_FREQ) {
+ dev_err(dev,
+ "%s(): proximity: Mask value 0x%08lx is not supported\n",
+ __func__, mask);
+ break;
+ }
+
+ if (val < 1 || val > 100) {
+ dev_err(dev,
+ "%s(): proximity: Sampling frequency %d is not in the range [1:100]\n",
+ __func__, val);
+ break;
+ }
+
+ ret = isl29028_set_proxim_sampling(chip, val, val2);
+ break;
+ case IIO_LIGHT:
+ if (mask != IIO_CHAN_INFO_SCALE) {
+ dev_err(dev,
+ "%s(): light: Mask value 0x%08lx is not supported\n",
+ __func__, mask);
+ break;
+ }
+
+ if (val != 125 && val != 2000) {
+ dev_err(dev,
+ "%s(): light: Lux scale %d is not in the set {125, 2000}\n",
+ __func__, val);
+ break;
+ }
+
+ ret = isl29028_set_als_scale(chip, val);
+ break;
+ default:
+ dev_err(dev, "%s(): Unsupported channel type %x\n",
+ __func__, chan->type);
+ break;
+ }
+
+ mutex_unlock(&chip->lock);
+
+ if (ret < 0)
+ return ret;
+
+ ret = isl29028_set_pm_runtime_busy(chip, false);
+ if (ret < 0)
+ return ret;
+
+ return ret;
+}
+
+static int isl29028_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct isl29028_chip *chip = iio_priv(indio_dev);
+ struct device *dev = regmap_get_device(chip->regmap);
+ int ret, pm_ret;
+
+ ret = isl29028_set_pm_runtime_busy(chip, true);
+ if (ret < 0)
+ return ret;
+
+ mutex_lock(&chip->lock);
+
+ ret = -EINVAL;
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ case IIO_CHAN_INFO_PROCESSED:
+ switch (chan->type) {
+ case IIO_LIGHT:
+ ret = isl29028_als_get(chip, val);
+ break;
+ case IIO_INTENSITY:
+ ret = isl29028_ir_get(chip, val);
+ break;
+ case IIO_PROXIMITY:
+ ret = isl29028_read_proxim(chip, val);
+ break;
+ default:
+ break;
+ }
+
+ if (ret < 0)
+ break;
+
+ ret = IIO_VAL_INT;
+ break;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ if (chan->type != IIO_PROXIMITY)
+ break;
+
+ *val = chip->prox_sampling_int;
+ *val2 = chip->prox_sampling_frac;
+ ret = IIO_VAL_INT;
+ break;
+ case IIO_CHAN_INFO_SCALE:
+ if (chan->type != IIO_LIGHT)
+ break;
+ *val = chip->lux_scale;
+ ret = IIO_VAL_INT;
+ break;
+ default:
+ dev_err(dev, "%s(): mask value 0x%08lx is not supported\n",
+ __func__, mask);
+ break;
+ }
+
+ mutex_unlock(&chip->lock);
+
+ if (ret < 0)
+ return ret;
+
+ /**
+ * Preserve the ret variable if the call to
+ * isl29028_set_pm_runtime_busy() is successful so the reading
+ * (if applicable) is returned to user space.
+ */
+ pm_ret = isl29028_set_pm_runtime_busy(chip, false);
+ if (pm_ret < 0)
+ return pm_ret;
+
+ return ret;
+}
+
+static IIO_CONST_ATTR(in_proximity_sampling_frequency_available,
+ "1.25 2.5 5 10 13.3 20 80 100");
+static IIO_CONST_ATTR(in_illuminance_scale_available, "125 2000");
+
+#define ISL29028_CONST_ATTR(name) (&iio_const_attr_##name.dev_attr.attr)
+static struct attribute *isl29028_attributes[] = {
+ ISL29028_CONST_ATTR(in_proximity_sampling_frequency_available),
+ ISL29028_CONST_ATTR(in_illuminance_scale_available),
+ NULL,
+};
+
+static const struct attribute_group isl29108_group = {
+ .attrs = isl29028_attributes,
+};
+
+static const struct iio_chan_spec isl29028_channels[] = {
+ {
+ .type = IIO_LIGHT,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ }, {
+ .type = IIO_INTENSITY,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ }, {
+ .type = IIO_PROXIMITY,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SAMP_FREQ),
+ }
+};
+
+static const struct iio_info isl29028_info = {
+ .attrs = &isl29108_group,
+ .read_raw = isl29028_read_raw,
+ .write_raw = isl29028_write_raw,
+};
+
+static int isl29028_clear_configure_reg(struct isl29028_chip *chip)
+{
+ struct device *dev = regmap_get_device(chip->regmap);
+ int ret;
+
+ ret = regmap_write(chip->regmap, ISL29028_REG_CONFIGURE, 0x0);
+ if (ret < 0)
+ dev_err(dev, "%s(): Error %d clearing the CONFIGURE register\n",
+ __func__, ret);
+
+ chip->als_ir_mode = ISL29028_MODE_NONE;
+ chip->enable_prox = false;
+
+ return ret;
+}
+
+static bool isl29028_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case ISL29028_REG_INTERRUPT:
+ case ISL29028_REG_PROX_DATA:
+ case ISL29028_REG_ALSIR_L:
+ case ISL29028_REG_ALSIR_U:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static const struct regmap_config isl29028_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .volatile_reg = isl29028_is_volatile_reg,
+ .max_register = ISL29028_NUM_REGS - 1,
+ .num_reg_defaults_raw = ISL29028_NUM_REGS,
+ .cache_type = REGCACHE_RBTREE,
+};
+
+static int isl29028_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct isl29028_chip *chip;
+ struct iio_dev *indio_dev;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ chip = iio_priv(indio_dev);
+
+ i2c_set_clientdata(client, indio_dev);
+ mutex_init(&chip->lock);
+
+ chip->regmap = devm_regmap_init_i2c(client, &isl29028_regmap_config);
+ if (IS_ERR(chip->regmap)) {
+ ret = PTR_ERR(chip->regmap);
+ dev_err(&client->dev, "%s: Error %d initializing regmap\n",
+ __func__, ret);
+ return ret;
+ }
+
+ chip->enable_prox = false;
+ chip->prox_sampling_int = 20;
+ chip->prox_sampling_frac = 0;
+ chip->lux_scale = 2000;
+
+ ret = regmap_write(chip->regmap, ISL29028_REG_TEST1_MODE, 0x0);
+ if (ret < 0) {
+ dev_err(&client->dev,
+ "%s(): Error %d writing to TEST1_MODE register\n",
+ __func__, ret);
+ return ret;
+ }
+
+ ret = regmap_write(chip->regmap, ISL29028_REG_TEST2_MODE, 0x0);
+ if (ret < 0) {
+ dev_err(&client->dev,
+ "%s(): Error %d writing to TEST2_MODE register\n",
+ __func__, ret);
+ return ret;
+ }
+
+ ret = isl29028_clear_configure_reg(chip);
+ if (ret < 0)
+ return ret;
+
+ indio_dev->info = &isl29028_info;
+ indio_dev->channels = isl29028_channels;
+ indio_dev->num_channels = ARRAY_SIZE(isl29028_channels);
+ indio_dev->name = id->name;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ pm_runtime_enable(&client->dev);
+ pm_runtime_set_autosuspend_delay(&client->dev,
+ ISL29028_POWER_OFF_DELAY_MS);
+ pm_runtime_use_autosuspend(&client->dev);
+
+ ret = iio_device_register(indio_dev);
+ if (ret < 0) {
+ dev_err(&client->dev,
+ "%s(): iio registration failed with error %d\n",
+ __func__, ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int isl29028_remove(struct i2c_client *client)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(client);
+ struct isl29028_chip *chip = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+
+ pm_runtime_disable(&client->dev);
+ pm_runtime_set_suspended(&client->dev);
+ pm_runtime_put_noidle(&client->dev);
+
+ return isl29028_clear_configure_reg(chip);
+}
+
+static int __maybe_unused isl29028_suspend(struct device *dev)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct isl29028_chip *chip = iio_priv(indio_dev);
+ int ret;
+
+ mutex_lock(&chip->lock);
+
+ ret = isl29028_clear_configure_reg(chip);
+
+ mutex_unlock(&chip->lock);
+
+ return ret;
+}
+
+static int __maybe_unused isl29028_resume(struct device *dev)
+{
+ /**
+ * The specific component (ALS/IR or proximity) will enable itself as
+ * needed the next time that the user requests a reading. This is done
+ * above in isl29028_set_als_ir_mode() and isl29028_enable_proximity().
+ */
+ return 0;
+}
+
+static const struct dev_pm_ops isl29028_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SET_RUNTIME_PM_OPS(isl29028_suspend, isl29028_resume, NULL)
+};
+
+static const struct i2c_device_id isl29028_id[] = {
+ {"isl29028", 0},
+ {"isl29030", 0},
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, isl29028_id);
+
+static const struct of_device_id isl29028_of_match[] = {
+ { .compatible = "isl,isl29028", }, /* for backward compat., don't use */
+ { .compatible = "isil,isl29028", },
+ { .compatible = "isil,isl29030", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, isl29028_of_match);
+
+static struct i2c_driver isl29028_driver = {
+ .driver = {
+ .name = "isl29028",
+ .pm = &isl29028_pm_ops,
+ .of_match_table = isl29028_of_match,
+ },
+ .probe = isl29028_probe,
+ .remove = isl29028_remove,
+ .id_table = isl29028_id,
+};
+
+module_i2c_driver(isl29028_driver);
+
+MODULE_DESCRIPTION("ISL29028 Ambient Light and Proximity Sensor driver");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");