linux/drivers/iio/light/rpr0521.c
Daniel Baluta efa86e9fa8 iio: light: Add support for ROHM RPR0521 sensor
This patch adds support for ROHM RPR0521 ambient light and proximity
sensor. It offers raw readings for intensity and proximity.

Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-06-21 15:14:54 +01:00

616 lines
14 KiB
C

/*
* RPR-0521 ROHM 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 RPR-0521RS (7-bit I2C slave address 0x38).
*
* TODO: illuminance channel, PM support, buffer
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/regmap.h>
#include <linux/delay.h>
#include <linux/acpi.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/pm_runtime.h>
#define RPR0521_REG_SYSTEM_CTRL 0x40
#define RPR0521_REG_MODE_CTRL 0x41
#define RPR0521_REG_ALS_CTRL 0x42
#define RPR0521_REG_PXS_CTRL 0x43
#define RPR0521_REG_PXS_DATA 0x44 /* 16-bit, little endian */
#define RPR0521_REG_ALS_DATA0 0x46 /* 16-bit, little endian */
#define RPR0521_REG_ALS_DATA1 0x48 /* 16-bit, little endian */
#define RPR0521_REG_ID 0x92
#define RPR0521_MODE_ALS_MASK BIT(7)
#define RPR0521_MODE_PXS_MASK BIT(6)
#define RPR0521_MODE_MEAS_TIME_MASK GENMASK(3, 0)
#define RPR0521_ALS_DATA0_GAIN_MASK GENMASK(5, 4)
#define RPR0521_ALS_DATA0_GAIN_SHIFT 4
#define RPR0521_ALS_DATA1_GAIN_MASK GENMASK(3, 2)
#define RPR0521_ALS_DATA1_GAIN_SHIFT 2
#define RPR0521_PXS_GAIN_MASK GENMASK(5, 4)
#define RPR0521_PXS_GAIN_SHIFT 4
#define RPR0521_MODE_ALS_ENABLE BIT(7)
#define RPR0521_MODE_ALS_DISABLE 0x00
#define RPR0521_MODE_PXS_ENABLE BIT(6)
#define RPR0521_MODE_PXS_DISABLE 0x00
#define RPR0521_MANUFACT_ID 0xE0
#define RPR0521_DEFAULT_MEAS_TIME 0x06 /* ALS - 100ms, PXS - 100ms */
#define RPR0521_DRV_NAME "RPR0521"
#define RPR0521_REGMAP_NAME "rpr0521_regmap"
#define RPR0521_SLEEP_DELAY_MS 2000
#define RPR0521_ALS_SCALE_AVAIL "0.007812 0.015625 0.5 1"
#define RPR0521_PXS_SCALE_AVAIL "0.125 0.5 1"
struct rpr0521_gain {
int scale;
int uscale;
};
static const struct rpr0521_gain rpr0521_als_gain[4] = {
{1, 0}, /* x1 */
{0, 500000}, /* x2 */
{0, 15625}, /* x64 */
{0, 7812}, /* x128 */
};
static const struct rpr0521_gain rpr0521_pxs_gain[3] = {
{1, 0}, /* x1 */
{0, 500000}, /* x2 */
{0, 125000}, /* x4 */
};
enum rpr0521_channel {
RPR0521_CHAN_ALS_DATA0,
RPR0521_CHAN_ALS_DATA1,
RPR0521_CHAN_PXS,
};
struct rpr0521_reg_desc {
u8 address;
u8 device_mask;
};
static const struct rpr0521_reg_desc rpr0521_data_reg[] = {
[RPR0521_CHAN_ALS_DATA0] = {
.address = RPR0521_REG_ALS_DATA0,
.device_mask = RPR0521_MODE_ALS_MASK,
},
[RPR0521_CHAN_ALS_DATA1] = {
.address = RPR0521_REG_ALS_DATA1,
.device_mask = RPR0521_MODE_ALS_MASK,
},
[RPR0521_CHAN_PXS] = {
.address = RPR0521_REG_PXS_DATA,
.device_mask = RPR0521_MODE_PXS_MASK,
},
};
static const struct rpr0521_gain_info {
u8 reg;
u8 mask;
u8 shift;
const struct rpr0521_gain *gain;
int size;
} rpr0521_gain[] = {
[RPR0521_CHAN_ALS_DATA0] = {
.reg = RPR0521_REG_ALS_CTRL,
.mask = RPR0521_ALS_DATA0_GAIN_MASK,
.shift = RPR0521_ALS_DATA0_GAIN_SHIFT,
.gain = rpr0521_als_gain,
.size = ARRAY_SIZE(rpr0521_als_gain),
},
[RPR0521_CHAN_ALS_DATA1] = {
.reg = RPR0521_REG_ALS_CTRL,
.mask = RPR0521_ALS_DATA1_GAIN_MASK,
.shift = RPR0521_ALS_DATA1_GAIN_SHIFT,
.gain = rpr0521_als_gain,
.size = ARRAY_SIZE(rpr0521_als_gain),
},
[RPR0521_CHAN_PXS] = {
.reg = RPR0521_REG_PXS_CTRL,
.mask = RPR0521_PXS_GAIN_MASK,
.shift = RPR0521_PXS_GAIN_SHIFT,
.gain = rpr0521_pxs_gain,
.size = ARRAY_SIZE(rpr0521_pxs_gain),
},
};
struct rpr0521_data {
struct i2c_client *client;
/* protect device params updates (e.g state, gain) */
struct mutex lock;
/* device active status */
bool als_dev_en;
bool pxs_dev_en;
/* optimize runtime pm ops - enable device only if needed */
bool als_ps_need_en;
bool pxs_ps_need_en;
struct regmap *regmap;
};
static IIO_CONST_ATTR(in_intensity_scale_available, RPR0521_ALS_SCALE_AVAIL);
static IIO_CONST_ATTR(in_proximity_scale_available, RPR0521_PXS_SCALE_AVAIL);
static struct attribute *rpr0521_attributes[] = {
&iio_const_attr_in_intensity_scale_available.dev_attr.attr,
&iio_const_attr_in_proximity_scale_available.dev_attr.attr,
NULL,
};
static const struct attribute_group rpr0521_attribute_group = {
.attrs = rpr0521_attributes,
};
static const struct iio_chan_spec rpr0521_channels[] = {
{
.type = IIO_INTENSITY,
.modified = 1,
.address = RPR0521_CHAN_ALS_DATA0,
.channel2 = IIO_MOD_LIGHT_BOTH,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
},
{
.type = IIO_INTENSITY,
.modified = 1,
.address = RPR0521_CHAN_ALS_DATA1,
.channel2 = IIO_MOD_LIGHT_IR,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
},
{
.type = IIO_PROXIMITY,
.address = RPR0521_CHAN_PXS,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
}
};
static int rpr0521_als_enable(struct rpr0521_data *data, u8 status)
{
int ret;
ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
RPR0521_MODE_ALS_MASK,
status);
if (ret < 0)
return ret;
data->als_dev_en = true;
return 0;
}
static int rpr0521_pxs_enable(struct rpr0521_data *data, u8 status)
{
int ret;
ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
RPR0521_MODE_PXS_MASK,
status);
if (ret < 0)
return ret;
data->pxs_dev_en = true;
return 0;
}
/**
* rpr0521_set_power_state - handles runtime PM state and sensors enabled status
*
* @data: rpr0521 device private data
* @on: state to be set for devices in @device_mask
* @device_mask: bitmask specifying for which device we need to update @on state
*
* We rely on rpr0521_runtime_resume to enable our @device_mask devices, but
* if (for example) PXS was enabled (pxs_dev_en = true) by a previous call to
* rpr0521_runtime_resume and we want to enable ALS we MUST set ALS enable
* bit of RPR0521_REG_MODE_CTRL here because rpr0521_runtime_resume will not
* be called twice.
*/
static int rpr0521_set_power_state(struct rpr0521_data *data, bool on,
u8 device_mask)
{
#ifdef CONFIG_PM
int ret;
u8 update_mask = 0;
if (device_mask & RPR0521_MODE_ALS_MASK) {
if (on && !data->als_ps_need_en && data->pxs_dev_en)
update_mask |= RPR0521_MODE_ALS_MASK;
else
data->als_ps_need_en = on;
}
if (device_mask & RPR0521_MODE_PXS_MASK) {
if (on && !data->pxs_ps_need_en && data->als_dev_en)
update_mask |= RPR0521_MODE_PXS_MASK;
else
data->pxs_ps_need_en = on;
}
if (update_mask) {
ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
update_mask, update_mask);
if (ret < 0)
return ret;
}
if (on) {
ret = pm_runtime_get_sync(&data->client->dev);
} else {
pm_runtime_mark_last_busy(&data->client->dev);
ret = pm_runtime_put_autosuspend(&data->client->dev);
}
if (ret < 0) {
dev_err(&data->client->dev,
"Failed: rpr0521_set_power_state for %d, ret %d\n",
on, ret);
if (on)
pm_runtime_put_noidle(&data->client->dev);
return ret;
}
#endif
return 0;
}
static int rpr0521_get_gain(struct rpr0521_data *data, int chan,
int *val, int *val2)
{
int ret, reg, idx;
ret = regmap_read(data->regmap, rpr0521_gain[chan].reg, &reg);
if (ret < 0)
return ret;
idx = (rpr0521_gain[chan].mask & reg) >> rpr0521_gain[chan].shift;
*val = rpr0521_gain[chan].gain[idx].scale;
*val2 = rpr0521_gain[chan].gain[idx].uscale;
return 0;
}
static int rpr0521_set_gain(struct rpr0521_data *data, int chan,
int val, int val2)
{
int i, idx = -EINVAL;
/* get gain index */
for (i = 0; i < rpr0521_gain[chan].size; i++)
if (val == rpr0521_gain[chan].gain[i].scale &&
val2 == rpr0521_gain[chan].gain[i].uscale) {
idx = i;
break;
}
if (idx < 0)
return idx;
return regmap_update_bits(data->regmap, rpr0521_gain[chan].reg,
rpr0521_gain[chan].mask,
idx << rpr0521_gain[chan].shift);
}
static int rpr0521_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int *val,
int *val2, long mask)
{
struct rpr0521_data *data = iio_priv(indio_dev);
int ret;
u8 device_mask;
__le16 raw_data;
switch (mask) {
case IIO_CHAN_INFO_RAW:
if (chan->type != IIO_INTENSITY && chan->type != IIO_PROXIMITY)
return -EINVAL;
device_mask = rpr0521_data_reg[chan->address].device_mask;
mutex_lock(&data->lock);
ret = rpr0521_set_power_state(data, true, device_mask);
if (ret < 0) {
mutex_unlock(&data->lock);
return ret;
}
ret = regmap_bulk_read(data->regmap,
rpr0521_data_reg[chan->address].address,
&raw_data, 2);
if (ret < 0) {
rpr0521_set_power_state(data, false, device_mask);
mutex_unlock(&data->lock);
return ret;
}
ret = rpr0521_set_power_state(data, false, device_mask);
mutex_unlock(&data->lock);
if (ret < 0)
return ret;
*val = le16_to_cpu(raw_data);
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
mutex_lock(&data->lock);
ret = rpr0521_get_gain(data, chan->address, val, val2);
mutex_unlock(&data->lock);
if (ret < 0)
return ret;
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
}
static int rpr0521_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int val,
int val2, long mask)
{
struct rpr0521_data *data = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_SCALE:
mutex_lock(&data->lock);
ret = rpr0521_set_gain(data, chan->address, val, val2);
mutex_unlock(&data->lock);
return ret;
default:
return -EINVAL;
}
}
static const struct iio_info rpr0521_info = {
.driver_module = THIS_MODULE,
.read_raw = rpr0521_read_raw,
.write_raw = rpr0521_write_raw,
.attrs = &rpr0521_attribute_group,
};
static int rpr0521_init(struct rpr0521_data *data)
{
int ret;
int id;
ret = regmap_read(data->regmap, RPR0521_REG_ID, &id);
if (ret < 0) {
dev_err(&data->client->dev, "Failed to read REG_ID register\n");
return ret;
}
if (id != RPR0521_MANUFACT_ID) {
dev_err(&data->client->dev, "Wrong id, got %x, expected %x\n",
id, RPR0521_MANUFACT_ID);
return -ENODEV;
}
/* set default measurement time - 100 ms for both ALS and PS */
ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
RPR0521_MODE_MEAS_TIME_MASK,
RPR0521_DEFAULT_MEAS_TIME);
if (ret) {
pr_err("regmap_update_bits returned %d\n", ret);
return ret;
}
ret = rpr0521_als_enable(data, RPR0521_MODE_ALS_ENABLE);
if (ret < 0)
return ret;
ret = rpr0521_pxs_enable(data, RPR0521_MODE_PXS_ENABLE);
if (ret < 0)
return ret;
return 0;
}
static int rpr0521_poweroff(struct rpr0521_data *data)
{
int ret;
ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
RPR0521_MODE_ALS_MASK |
RPR0521_MODE_PXS_MASK,
RPR0521_MODE_ALS_DISABLE |
RPR0521_MODE_PXS_DISABLE);
if (ret < 0)
return ret;
data->als_dev_en = false;
data->pxs_dev_en = false;
return 0;
}
static bool rpr0521_is_volatile_reg(struct device *dev, unsigned int reg)
{
switch (reg) {
case RPR0521_REG_MODE_CTRL:
case RPR0521_REG_ALS_CTRL:
case RPR0521_REG_PXS_CTRL:
return false;
default:
return true;
}
}
static const struct regmap_config rpr0521_regmap_config = {
.name = RPR0521_REGMAP_NAME,
.reg_bits = 8,
.val_bits = 8,
.max_register = RPR0521_REG_ID,
.cache_type = REGCACHE_RBTREE,
.volatile_reg = rpr0521_is_volatile_reg,
};
static int rpr0521_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct rpr0521_data *data;
struct iio_dev *indio_dev;
struct regmap *regmap;
int ret;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
regmap = devm_regmap_init_i2c(client, &rpr0521_regmap_config);
if (IS_ERR(regmap)) {
dev_err(&client->dev, "regmap_init failed!\n");
return PTR_ERR(regmap);
}
data = iio_priv(indio_dev);
i2c_set_clientdata(client, indio_dev);
data->client = client;
data->regmap = regmap;
mutex_init(&data->lock);
indio_dev->dev.parent = &client->dev;
indio_dev->info = &rpr0521_info;
indio_dev->name = RPR0521_DRV_NAME;
indio_dev->channels = rpr0521_channels;
indio_dev->num_channels = ARRAY_SIZE(rpr0521_channels);
indio_dev->modes = INDIO_DIRECT_MODE;
ret = rpr0521_init(data);
if (ret < 0) {
dev_err(&client->dev, "rpr0521 chip init failed\n");
return ret;
}
ret = iio_device_register(indio_dev);
if (ret < 0)
return ret;
ret = pm_runtime_set_active(&client->dev);
if (ret < 0)
goto err_iio_unregister;
pm_runtime_enable(&client->dev);
pm_runtime_set_autosuspend_delay(&client->dev, RPR0521_SLEEP_DELAY_MS);
pm_runtime_use_autosuspend(&client->dev);
return 0;
err_iio_unregister:
iio_device_unregister(indio_dev);
return ret;
}
static int rpr0521_remove(struct i2c_client *client)
{
struct iio_dev *indio_dev = i2c_get_clientdata(client);
pm_runtime_disable(&client->dev);
pm_runtime_set_suspended(&client->dev);
pm_runtime_put_noidle(&client->dev);
iio_device_unregister(indio_dev);
rpr0521_poweroff(iio_priv(indio_dev));
return 0;
}
#ifdef CONFIG_PM
static int rpr0521_runtime_suspend(struct device *dev)
{
struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
struct rpr0521_data *data = iio_priv(indio_dev);
int ret;
/* disable channels and sets {als,pxs}_dev_en to false */
mutex_lock(&data->lock);
ret = rpr0521_poweroff(data);
mutex_unlock(&data->lock);
return ret;
}
static int rpr0521_runtime_resume(struct device *dev)
{
struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
struct rpr0521_data *data = iio_priv(indio_dev);
int ret;
if (data->als_ps_need_en) {
ret = rpr0521_als_enable(data, RPR0521_MODE_ALS_ENABLE);
if (ret < 0)
return ret;
data->als_ps_need_en = false;
}
if (data->pxs_ps_need_en) {
ret = rpr0521_pxs_enable(data, RPR0521_MODE_PXS_ENABLE);
if (ret < 0)
return ret;
data->pxs_ps_need_en = false;
}
return 0;
}
#endif
static const struct dev_pm_ops rpr0521_pm_ops = {
SET_RUNTIME_PM_OPS(rpr0521_runtime_suspend,
rpr0521_runtime_resume, NULL)
};
static const struct acpi_device_id rpr0521_acpi_match[] = {
{"RPR0521", 0},
{ }
};
MODULE_DEVICE_TABLE(acpi, rpr0521_acpi_match);
static const struct i2c_device_id rpr0521_id[] = {
{"rpr0521", 0},
{ }
};
MODULE_DEVICE_TABLE(i2c, rpr0521_id);
static struct i2c_driver rpr0521_driver = {
.driver = {
.name = RPR0521_DRV_NAME,
.pm = &rpr0521_pm_ops,
.acpi_match_table = ACPI_PTR(rpr0521_acpi_match),
},
.probe = rpr0521_probe,
.remove = rpr0521_remove,
.id_table = rpr0521_id,
};
module_i2c_driver(rpr0521_driver);
MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
MODULE_DESCRIPTION("RPR0521 ROHM Ambient Light and Proximity Sensor driver");
MODULE_LICENSE("GPL v2");