diff options
Diffstat (limited to 'drivers/iio/light/stk3310.c')
| -rw-r--r-- | drivers/iio/light/stk3310.c | 696 |
1 files changed, 696 insertions, 0 deletions
diff --git a/drivers/iio/light/stk3310.c b/drivers/iio/light/stk3310.c new file mode 100644 index 000000000..4cfa0101b --- /dev/null +++ b/drivers/iio/light/stk3310.c @@ -0,0 +1,696 @@ +/** + * 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/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 BIT(0) +#define STK3310_STATE_EN_ALS BIT(1) +#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_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; + __be16 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 = be16_to_cpu(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; + __be16 buf; + int ret; + unsigned int index; + struct stk3310_data *data = iio_priv(indio_dev); + struct i2c_client *client = data->client; + + ret = regmap_field_read(data->reg_ps_gain, &index); + if (ret < 0) + return ret; + + if (val < 0 || 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 = cpu_to_be16(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; + int ret; + struct stk3310_data *data = iio_priv(indio_dev); + + ret = regmap_field_read(data->reg_int_ps, &event_val); + if (ret < 0) + return ret; + + 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; + __be16 buf; + int ret; + unsigned int index; + struct stk3310_data *data = iio_priv(indio_dev); + struct i2c_client *client = data->client; + + if (chan->type != IIO_LIGHT && chan->type != IIO_PROXIMITY) + return -EINVAL; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + if (chan->type == IIO_LIGHT) + reg = STK3310_REG_ALS_DATA_MSB; + else + reg = STK3310_REG_PS_DATA_MSB; + + 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 = be16_to_cpu(buf); + mutex_unlock(&data->lock); + return IIO_VAL_INT; + case IIO_CHAN_INFO_INT_TIME: + if (chan->type == IIO_LIGHT) + ret = regmap_field_read(data->reg_als_it, &index); + else + ret = regmap_field_read(data->reg_ps_it, &index); + if (ret < 0) + return ret; + + *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) + ret = regmap_field_read(data->reg_als_gain, &index); + else + ret = regmap_field_read(data->reg_ps_gain, &index); + if (ret < 0) + return ret; + + *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); + + if (chan->type != IIO_LIGHT && chan->type != IIO_PROXIMITY) + return -EINVAL; + + 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 = { + .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 & STK3310_STATE_EN_PS); + data->als_enabled = !!(state & STK3310_STATE_EN_ALS); + } + 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; + + ret = regmap_read(data->regmap, STK3310_REG_ID, &chipid); + if (ret < 0) + return ret; + + 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 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(indio_dev); + + 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: %d\n", ret); + goto out; + } + 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"); +out: + 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; + + 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); + goto err_standby; + } + } + + ret = iio_device_register(indio_dev); + if (ret < 0) { + dev_err(&client->dev, "device_register failed\n"); + goto err_standby; + } + + return 0; + +err_standby: + stk3310_set_state(data, STK3310_STATE_STANDBY); + 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) +{ + u8 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}, + {} +}; +MODULE_DEVICE_TABLE(i2c, stk3310_i2c_id); + +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"); |