linux/drivers/iio/light/stk3310.c
Tiberiu Breana 0f16fc8bb3 iio: light: STK3310: un-invert proximity values
In accordance with the recent proximity ABI changes,
STK3310's proximity readings should be un-inversed
in order to return low values for far-away objects
and high values for close ones.

As consequences of this change, iio event directions
have been switched and maximum proximity sensor
reference values have also been adjusted in accordance
with the real readings.

Signed-off-by: Tiberiu Breana <tiberiu.a.breana@intel.com>
Acked-by: Hartmut Knaack <knaack.h@gmx.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-07-19 11:48:12 +01:00

704 lines
18 KiB
C

/**
* Sensortek STK3310/STK3311 Ambient Light and Proximity Sensor
*
* Copyright (c) 2015, Intel Corporation.
*
* This file is subject to the terms and conditions of version 2 of
* the GNU General Public License. See the file COPYING in the main
* directory of this archive for more details.
*
* IIO driver for STK3310/STK3311. 7-bit I2C address: 0x48.
*/
#include <linux/acpi.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/gpio/consumer.h>
#include <linux/iio/events.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#define STK3310_REG_STATE 0x00
#define STK3310_REG_PSCTRL 0x01
#define STK3310_REG_ALSCTRL 0x02
#define STK3310_REG_INT 0x04
#define STK3310_REG_THDH_PS 0x06
#define STK3310_REG_THDL_PS 0x08
#define STK3310_REG_FLAG 0x10
#define STK3310_REG_PS_DATA_MSB 0x11
#define STK3310_REG_PS_DATA_LSB 0x12
#define STK3310_REG_ALS_DATA_MSB 0x13
#define STK3310_REG_ALS_DATA_LSB 0x14
#define STK3310_REG_ID 0x3E
#define STK3310_MAX_REG 0x80
#define STK3310_STATE_EN_PS 0x01
#define STK3310_STATE_EN_ALS 0x02
#define STK3310_STATE_STANDBY 0x00
#define STK3310_CHIP_ID_VAL 0x13
#define STK3311_CHIP_ID_VAL 0x1D
#define STK3310_PSINT_EN 0x01
#define STK3310_PS_MAX_VAL 0xFFFF
#define STK3310_DRIVER_NAME "stk3310"
#define STK3310_REGMAP_NAME "stk3310_regmap"
#define STK3310_EVENT "stk3310_event"
#define STK3310_GPIO "stk3310_gpio"
#define STK3310_SCALE_AVAILABLE "6.4 1.6 0.4 0.1"
#define STK3310_IT_AVAILABLE \
"0.000185 0.000370 0.000741 0.001480 0.002960 0.005920 0.011840 " \
"0.023680 0.047360 0.094720 0.189440 0.378880 0.757760 1.515520 " \
"3.031040 6.062080"
#define STK3310_REGFIELD(name) \
do { \
data->reg_##name = \
devm_regmap_field_alloc(&client->dev, regmap, \
stk3310_reg_field_##name); \
if (IS_ERR(data->reg_##name)) { \
dev_err(&client->dev, "reg field alloc failed.\n"); \
return PTR_ERR(data->reg_##name); \
} \
} while (0)
static const struct reg_field stk3310_reg_field_state =
REG_FIELD(STK3310_REG_STATE, 0, 2);
static const struct reg_field stk3310_reg_field_als_gain =
REG_FIELD(STK3310_REG_ALSCTRL, 4, 5);
static const struct reg_field stk3310_reg_field_ps_gain =
REG_FIELD(STK3310_REG_PSCTRL, 4, 5);
static const struct reg_field stk3310_reg_field_als_it =
REG_FIELD(STK3310_REG_ALSCTRL, 0, 3);
static const struct reg_field stk3310_reg_field_ps_it =
REG_FIELD(STK3310_REG_PSCTRL, 0, 3);
static const struct reg_field stk3310_reg_field_int_ps =
REG_FIELD(STK3310_REG_INT, 0, 2);
static const struct reg_field stk3310_reg_field_flag_psint =
REG_FIELD(STK3310_REG_FLAG, 4, 4);
static const struct reg_field stk3310_reg_field_flag_nf =
REG_FIELD(STK3310_REG_FLAG, 0, 0);
/* Estimate maximum proximity values with regard to measurement scale. */
static const int stk3310_ps_max[4] = {
STK3310_PS_MAX_VAL / 640,
STK3310_PS_MAX_VAL / 160,
STK3310_PS_MAX_VAL / 40,
STK3310_PS_MAX_VAL / 10
};
static const int stk3310_scale_table[][2] = {
{6, 400000}, {1, 600000}, {0, 400000}, {0, 100000}
};
/* Integration time in seconds, microseconds */
static const int stk3310_it_table[][2] = {
{0, 185}, {0, 370}, {0, 741}, {0, 1480},
{0, 2960}, {0, 5920}, {0, 11840}, {0, 23680},
{0, 47360}, {0, 94720}, {0, 189440}, {0, 378880},
{0, 757760}, {1, 515520}, {3, 31040}, {6, 62080},
};
struct stk3310_data {
struct i2c_client *client;
struct mutex lock;
bool als_enabled;
bool ps_enabled;
u64 timestamp;
struct regmap *regmap;
struct regmap_field *reg_state;
struct regmap_field *reg_als_gain;
struct regmap_field *reg_ps_gain;
struct regmap_field *reg_als_it;
struct regmap_field *reg_ps_it;
struct regmap_field *reg_int_ps;
struct regmap_field *reg_flag_psint;
struct regmap_field *reg_flag_nf;
};
static const struct iio_event_spec stk3310_events[] = {
/* Proximity event */
{
.type = IIO_EV_TYPE_THRESH,
.dir = IIO_EV_DIR_RISING,
.mask_separate = BIT(IIO_EV_INFO_VALUE) |
BIT(IIO_EV_INFO_ENABLE),
},
/* Out-of-proximity event */
{
.type = IIO_EV_TYPE_THRESH,
.dir = IIO_EV_DIR_FALLING,
.mask_separate = BIT(IIO_EV_INFO_VALUE) |
BIT(IIO_EV_INFO_ENABLE),
},
};
static const struct iio_chan_spec stk3310_channels[] = {
{
.type = IIO_LIGHT,
.info_mask_separate =
BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE) |
BIT(IIO_CHAN_INFO_INT_TIME),
},
{
.type = IIO_PROXIMITY,
.info_mask_separate =
BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE) |
BIT(IIO_CHAN_INFO_INT_TIME),
.event_spec = stk3310_events,
.num_event_specs = ARRAY_SIZE(stk3310_events),
}
};
static IIO_CONST_ATTR(in_illuminance_scale_available, STK3310_SCALE_AVAILABLE);
static IIO_CONST_ATTR(in_proximity_scale_available, STK3310_SCALE_AVAILABLE);
static IIO_CONST_ATTR(in_illuminance_integration_time_available,
STK3310_IT_AVAILABLE);
static IIO_CONST_ATTR(in_proximity_integration_time_available,
STK3310_IT_AVAILABLE);
static struct attribute *stk3310_attributes[] = {
&iio_const_attr_in_illuminance_scale_available.dev_attr.attr,
&iio_const_attr_in_proximity_scale_available.dev_attr.attr,
&iio_const_attr_in_illuminance_integration_time_available.dev_attr.attr,
&iio_const_attr_in_proximity_integration_time_available.dev_attr.attr,
NULL,
};
static const struct attribute_group stk3310_attribute_group = {
.attrs = stk3310_attributes
};
static int stk3310_get_index(const int table[][2], int table_size,
int val, int val2)
{
int i;
for (i = 0; i < table_size; i++) {
if (val == table[i][0] && val2 == table[i][1])
return i;
}
return -EINVAL;
}
static int stk3310_read_event(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)
{
u8 reg;
u16 buf;
int ret;
struct stk3310_data *data = iio_priv(indio_dev);
if (info != IIO_EV_INFO_VALUE)
return -EINVAL;
/* Only proximity interrupts are implemented at the moment. */
if (dir == IIO_EV_DIR_RISING)
reg = STK3310_REG_THDH_PS;
else if (dir == IIO_EV_DIR_FALLING)
reg = STK3310_REG_THDL_PS;
else
return -EINVAL;
mutex_lock(&data->lock);
ret = regmap_bulk_read(data->regmap, reg, &buf, 2);
mutex_unlock(&data->lock);
if (ret < 0) {
dev_err(&data->client->dev, "register read failed\n");
return ret;
}
*val = swab16(buf);
return IIO_VAL_INT;
}
static int stk3310_write_event(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)
{
u8 reg;
u16 buf;
int ret;
unsigned int index;
struct stk3310_data *data = iio_priv(indio_dev);
struct i2c_client *client = data->client;
regmap_field_read(data->reg_ps_gain, &index);
if (val > stk3310_ps_max[index])
return -EINVAL;
if (dir == IIO_EV_DIR_RISING)
reg = STK3310_REG_THDH_PS;
else if (dir == IIO_EV_DIR_FALLING)
reg = STK3310_REG_THDL_PS;
else
return -EINVAL;
buf = swab16(val);
ret = regmap_bulk_write(data->regmap, reg, &buf, 2);
if (ret < 0)
dev_err(&client->dev, "failed to set PS threshold!\n");
return ret;
}
static int stk3310_read_event_config(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum iio_event_type type,
enum iio_event_direction dir)
{
unsigned int event_val;
struct stk3310_data *data = iio_priv(indio_dev);
regmap_field_read(data->reg_int_ps, &event_val);
return event_val;
}
static int stk3310_write_event_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 stk3310_data *data = iio_priv(indio_dev);
struct i2c_client *client = data->client;
if (state < 0 || state > 7)
return -EINVAL;
/* Set INT_PS value */
mutex_lock(&data->lock);
ret = regmap_field_write(data->reg_int_ps, state);
if (ret < 0)
dev_err(&client->dev, "failed to set interrupt mode\n");
mutex_unlock(&data->lock);
return ret;
}
static int stk3310_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
u8 reg;
u16 buf;
int ret;
unsigned int index;
struct stk3310_data *data = iio_priv(indio_dev);
struct i2c_client *client = data->client;
switch (mask) {
case IIO_CHAN_INFO_RAW:
if (chan->type == IIO_LIGHT)
reg = STK3310_REG_ALS_DATA_MSB;
else if (chan->type == IIO_PROXIMITY)
reg = STK3310_REG_PS_DATA_MSB;
else
return -EINVAL;
mutex_lock(&data->lock);
ret = regmap_bulk_read(data->regmap, reg, &buf, 2);
if (ret < 0) {
dev_err(&client->dev, "register read failed\n");
mutex_unlock(&data->lock);
return ret;
}
*val = swab16(buf);
mutex_unlock(&data->lock);
return IIO_VAL_INT;
case IIO_CHAN_INFO_INT_TIME:
if (chan->type == IIO_LIGHT)
regmap_field_read(data->reg_als_it, &index);
else
regmap_field_read(data->reg_ps_it, &index);
*val = stk3310_it_table[index][0];
*val2 = stk3310_it_table[index][1];
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_SCALE:
if (chan->type == IIO_LIGHT)
regmap_field_read(data->reg_als_gain, &index);
else
regmap_field_read(data->reg_ps_gain, &index);
*val = stk3310_scale_table[index][0];
*val2 = stk3310_scale_table[index][1];
return IIO_VAL_INT_PLUS_MICRO;
}
return -EINVAL;
}
static int stk3310_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
int ret;
int index;
struct stk3310_data *data = iio_priv(indio_dev);
switch (mask) {
case IIO_CHAN_INFO_INT_TIME:
index = stk3310_get_index(stk3310_it_table,
ARRAY_SIZE(stk3310_it_table),
val, val2);
if (index < 0)
return -EINVAL;
mutex_lock(&data->lock);
if (chan->type == IIO_LIGHT)
ret = regmap_field_write(data->reg_als_it, index);
else
ret = regmap_field_write(data->reg_ps_it, index);
if (ret < 0)
dev_err(&data->client->dev,
"sensor configuration failed\n");
mutex_unlock(&data->lock);
return ret;
case IIO_CHAN_INFO_SCALE:
index = stk3310_get_index(stk3310_scale_table,
ARRAY_SIZE(stk3310_scale_table),
val, val2);
if (index < 0)
return -EINVAL;
mutex_lock(&data->lock);
if (chan->type == IIO_LIGHT)
ret = regmap_field_write(data->reg_als_gain, index);
else
ret = regmap_field_write(data->reg_ps_gain, index);
if (ret < 0)
dev_err(&data->client->dev,
"sensor configuration failed\n");
mutex_unlock(&data->lock);
return ret;
}
return -EINVAL;
}
static const struct iio_info stk3310_info = {
.driver_module = THIS_MODULE,
.read_raw = stk3310_read_raw,
.write_raw = stk3310_write_raw,
.attrs = &stk3310_attribute_group,
.read_event_value = stk3310_read_event,
.write_event_value = stk3310_write_event,
.read_event_config = stk3310_read_event_config,
.write_event_config = stk3310_write_event_config,
};
static int stk3310_set_state(struct stk3310_data *data, u8 state)
{
int ret;
struct i2c_client *client = data->client;
/* 3-bit state; 0b100 is not supported. */
if (state > 7 || state == 4)
return -EINVAL;
mutex_lock(&data->lock);
ret = regmap_field_write(data->reg_state, state);
if (ret < 0) {
dev_err(&client->dev, "failed to change sensor state\n");
} else if (state != STK3310_STATE_STANDBY) {
/* Don't reset the 'enabled' flags if we're going in standby */
data->ps_enabled = !!(state & 0x01);
data->als_enabled = !!(state & 0x02);
}
mutex_unlock(&data->lock);
return ret;
}
static int stk3310_init(struct iio_dev *indio_dev)
{
int ret;
int chipid;
u8 state;
struct stk3310_data *data = iio_priv(indio_dev);
struct i2c_client *client = data->client;
regmap_read(data->regmap, STK3310_REG_ID, &chipid);
if (chipid != STK3310_CHIP_ID_VAL &&
chipid != STK3311_CHIP_ID_VAL) {
dev_err(&client->dev, "invalid chip id: 0x%x\n", chipid);
return -ENODEV;
}
state = STK3310_STATE_EN_ALS | STK3310_STATE_EN_PS;
ret = stk3310_set_state(data, state);
if (ret < 0) {
dev_err(&client->dev, "failed to enable sensor");
return ret;
}
/* Enable PS interrupts */
ret = regmap_field_write(data->reg_int_ps, STK3310_PSINT_EN);
if (ret < 0)
dev_err(&client->dev, "failed to enable interrupts!\n");
return ret;
}
static int stk3310_gpio_probe(struct i2c_client *client)
{
struct device *dev;
struct gpio_desc *gpio;
int ret;
if (!client)
return -EINVAL;
dev = &client->dev;
/* gpio interrupt pin */
gpio = devm_gpiod_get_index(dev, STK3310_GPIO, 0);
if (IS_ERR(gpio)) {
dev_err(dev, "acpi gpio get index failed\n");
return PTR_ERR(gpio);
}
ret = gpiod_direction_input(gpio);
if (ret)
return ret;
ret = gpiod_to_irq(gpio);
dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret);
return ret;
}
static bool stk3310_is_volatile_reg(struct device *dev, unsigned int reg)
{
switch (reg) {
case STK3310_REG_ALS_DATA_MSB:
case STK3310_REG_ALS_DATA_LSB:
case STK3310_REG_PS_DATA_LSB:
case STK3310_REG_PS_DATA_MSB:
case STK3310_REG_FLAG:
return true;
default:
return false;
}
}
static struct regmap_config stk3310_regmap_config = {
.name = STK3310_REGMAP_NAME,
.reg_bits = 8,
.val_bits = 8,
.max_register = STK3310_MAX_REG,
.cache_type = REGCACHE_RBTREE,
.volatile_reg = stk3310_is_volatile_reg,
};
static int stk3310_regmap_init(struct stk3310_data *data)
{
struct regmap *regmap;
struct i2c_client *client;
client = data->client;
regmap = devm_regmap_init_i2c(client, &stk3310_regmap_config);
if (IS_ERR(regmap)) {
dev_err(&client->dev, "regmap initialization failed.\n");
return PTR_ERR(regmap);
}
data->regmap = regmap;
STK3310_REGFIELD(state);
STK3310_REGFIELD(als_gain);
STK3310_REGFIELD(ps_gain);
STK3310_REGFIELD(als_it);
STK3310_REGFIELD(ps_it);
STK3310_REGFIELD(int_ps);
STK3310_REGFIELD(flag_psint);
STK3310_REGFIELD(flag_nf);
return 0;
}
static irqreturn_t stk3310_irq_handler(int irq, void *private)
{
struct iio_dev *indio_dev = private;
struct stk3310_data *data = iio_priv(indio_dev);
data->timestamp = iio_get_time_ns();
return IRQ_WAKE_THREAD;
}
static irqreturn_t stk3310_irq_event_handler(int irq, void *private)
{
int ret;
unsigned int dir;
u64 event;
struct iio_dev *indio_dev = private;
struct stk3310_data *data = iio_priv(indio_dev);
/* Read FLAG_NF to figure out what threshold has been met. */
mutex_lock(&data->lock);
ret = regmap_field_read(data->reg_flag_nf, &dir);
if (ret < 0) {
dev_err(&data->client->dev, "register read failed\n");
mutex_unlock(&data->lock);
return ret;
}
event = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, 1,
IIO_EV_TYPE_THRESH,
(dir ? IIO_EV_DIR_FALLING :
IIO_EV_DIR_RISING));
iio_push_event(indio_dev, event, data->timestamp);
/* Reset the interrupt flag */
ret = regmap_field_write(data->reg_flag_psint, 0);
if (ret < 0)
dev_err(&data->client->dev, "failed to reset interrupts\n");
mutex_unlock(&data->lock);
return IRQ_HANDLED;
}
static int stk3310_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int ret;
struct iio_dev *indio_dev;
struct stk3310_data *data;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (!indio_dev) {
dev_err(&client->dev, "iio allocation failed!\n");
return -ENOMEM;
}
data = iio_priv(indio_dev);
data->client = client;
i2c_set_clientdata(client, indio_dev);
mutex_init(&data->lock);
ret = stk3310_regmap_init(data);
if (ret < 0)
return ret;
indio_dev->dev.parent = &client->dev;
indio_dev->info = &stk3310_info;
indio_dev->name = STK3310_DRIVER_NAME;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = stk3310_channels;
indio_dev->num_channels = ARRAY_SIZE(stk3310_channels);
ret = stk3310_init(indio_dev);
if (ret < 0)
return ret;
ret = iio_device_register(indio_dev);
if (ret < 0) {
dev_err(&client->dev, "device_register failed\n");
stk3310_set_state(data, STK3310_STATE_STANDBY);
}
if (client->irq <= 0)
client->irq = stk3310_gpio_probe(client);
if (client->irq >= 0) {
ret = devm_request_threaded_irq(&client->dev, client->irq,
stk3310_irq_handler,
stk3310_irq_event_handler,
IRQF_TRIGGER_FALLING |
IRQF_ONESHOT,
STK3310_EVENT, indio_dev);
if (ret < 0)
dev_err(&client->dev, "request irq %d failed\n",
client->irq);
}
return ret;
}
static int stk3310_remove(struct i2c_client *client)
{
struct iio_dev *indio_dev = i2c_get_clientdata(client);
iio_device_unregister(indio_dev);
return stk3310_set_state(iio_priv(indio_dev), STK3310_STATE_STANDBY);
}
#ifdef CONFIG_PM_SLEEP
static int stk3310_suspend(struct device *dev)
{
struct stk3310_data *data;
data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
return stk3310_set_state(data, STK3310_STATE_STANDBY);
}
static int stk3310_resume(struct device *dev)
{
int state = 0;
struct stk3310_data *data;
data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
if (data->ps_enabled)
state |= STK3310_STATE_EN_PS;
if (data->als_enabled)
state |= STK3310_STATE_EN_ALS;
return stk3310_set_state(data, state);
}
static SIMPLE_DEV_PM_OPS(stk3310_pm_ops, stk3310_suspend, stk3310_resume);
#define STK3310_PM_OPS (&stk3310_pm_ops)
#else
#define STK3310_PM_OPS NULL
#endif
static const struct i2c_device_id stk3310_i2c_id[] = {
{"STK3310", 0},
{"STK3311", 0},
{}
};
static const struct acpi_device_id stk3310_acpi_id[] = {
{"STK3310", 0},
{"STK3311", 0},
{}
};
MODULE_DEVICE_TABLE(acpi, stk3310_acpi_id);
static struct i2c_driver stk3310_driver = {
.driver = {
.name = "stk3310",
.pm = STK3310_PM_OPS,
.acpi_match_table = ACPI_PTR(stk3310_acpi_id),
},
.probe = stk3310_probe,
.remove = stk3310_remove,
.id_table = stk3310_i2c_id,
};
module_i2c_driver(stk3310_driver);
MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
MODULE_DESCRIPTION("STK3310 Ambient Light and Proximity Sensor driver");
MODULE_LICENSE("GPL v2");