On 16/03/16 01:06, Peter Meerwald-Stadler wrote: > ultraviolet (UV) light sensor with I2C interface with a peak > sensitivity at 355 nm > > strangely, chip uses two addresses 0x38 and 0x39 for LSB and > MSB data, resp. Novel - by which I mean PITA. > > datasheet: http://www.vishay.com/docs/84277/veml6070.pdf > > Signed-off-by: Peter Meerwald-Stadler <pmeerw@xxxxxxxxxx> Looks good to me - except the whole thing about uvindex as a channel type rather than a modifier. Jonathan > --- > drivers/iio/light/Kconfig | 10 ++ > drivers/iio/light/Makefile | 1 + > drivers/iio/light/veml6070.c | 220 +++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 231 insertions(+) > create mode 100644 drivers/iio/light/veml6070.c > > diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig > index cfd3df8..d2fe64e 100644 > --- a/drivers/iio/light/Kconfig > +++ b/drivers/iio/light/Kconfig > @@ -320,4 +320,14 @@ config VCNL4000 > To compile this driver as a module, choose M here: the > module will be called vcnl4000. > > +config VEML6070 > + tristate "VEML6070 UV A light sensor" > + depends on I2C > + help > + Say Y here if you want to build a driver for the Vishay VEML6070 UV A > + light sensor. > + > + To compile this driver as a module, choose M here: the > + module will be called veml6070. > + > endmenu > diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile > index b2c3105..a447c62 100644 > --- a/drivers/iio/light/Makefile > +++ b/drivers/iio/light/Makefile > @@ -30,3 +30,4 @@ obj-$(CONFIG_TCS3472) += tcs3472.o > obj-$(CONFIG_TSL4531) += tsl4531.o > obj-$(CONFIG_US5182D) += us5182d.o > obj-$(CONFIG_VCNL4000) += vcnl4000.o > +obj-$(CONFIG_VEML6070) += veml6070.o > diff --git a/drivers/iio/light/veml6070.c b/drivers/iio/light/veml6070.c > new file mode 100644 > index 0000000..d70b51e > --- /dev/null > +++ b/drivers/iio/light/veml6070.c > @@ -0,0 +1,220 @@ > +/* > + * veml6070.c - Support for Vishay VEML6070 UV A light sensor > + * > + * Copyright 2016 Peter Meerwald-Stadler <pmeerw@xxxxxxxxxx> > + * > + * 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 VEML6070 (7-bit I2C slave addresses 0x38 and 0x39) > + * > + * TODO: integration time, ACK signal > + */ > + > +#include <linux/module.h> > +#include <linux/i2c.h> > +#include <linux/mutex.h> > +#include <linux/err.h> > +#include <linux/delay.h> > + > +#include <linux/iio/iio.h> > +#include <linux/iio/sysfs.h> > + > +#define VEML6070_DRV_NAME "veml6070" > + > +#define VEML6070_ADDR_CONFIG_DATA_MSB 0x38 /* read: MSB data, write: config */ > +#define VEML6070_ADDR_DATA_LSB 0x39 /* LSB data */ > + > +#define VEML6070_COMMAND_ACK BIT(5) /* raise interrupt when over threshold */ > +#define VEML6070_COMMAND_IT GENMASK(3, 2) /* bit mask integration time */ > +#define VEML6070_COMMAND_RSRVD BIT(1) /* reserved, set to 1 */ > +#define VEML6070_COMMAND_SD BIT(0) /* shutdown mode when set */ > + > +#define VEML6070_IT_10 0x04 /* integration time 1x */ > + > +struct veml6070_data { > + struct i2c_client *client1; > + struct i2c_client *client2; > + u8 config; > + struct mutex lock; > +}; > + > +static int veml6070_read(struct veml6070_data *data) > +{ > + int ret; > + u8 msb, lsb; > + > + mutex_lock(&data->lock); > + > + /* disable shutdown */ > + ret = i2c_smbus_write_byte(data->client1, > + data->config & ~VEML6070_COMMAND_SD); > + if (ret < 0) > + goto out; > + > + msleep(125 + 10); /* measurement takes up to 125 ms for IT 1x */ > + > + ret = i2c_smbus_read_byte(data->client2); /* read MSB, address 0x39 */ > + if (ret < 0) > + goto out; > + msb = ret; > + > + ret = i2c_smbus_read_byte(data->client1); /* read LSB, address 0x38 */ > + if (ret < 0) > + goto out; > + lsb = ret; > + > + /* shutdown again */ > + ret = i2c_smbus_write_byte(data->client1, data->config); > + if (ret < 0) > + goto out; > + > + ret = (msb << 8) | lsb; > + > +out: > + mutex_unlock(&data->lock); > + return ret; > +} > + > +static const struct iio_chan_spec veml6070_channels[] = { > + { > + .type = IIO_INTENSITY, > + .modified = 1, > + .channel2 = IIO_MOD_LIGHT_UV, > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), > + }, > + { > + .type = IIO_INTENSITY, > + .modified = 1, > + .channel2 = IIO_MOD_LIGHT_UV_INDEX, > + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), > + } > +}; > + > +static int veml6070_to_uv_index(unsigned val) > +{ > + /* > + * conversion of raw UV intensity values to UV index depends on > + * integration time (IT) and value of the resistor connected to > + * the RSET pin (default: 270 KOhm) > + */ > + unsigned uvi[11] = { > + 187, 373, 560, /* low */ > + 746, 933, 1120, /* moderate */ > + 1308, 1494, /* high */ > + 1681, 1868, 2054}; /* very high */ > + int i; > + > + for (i = 0; i < ARRAY_SIZE(uvi); i++) > + if (val <= uvi[i]) > + return i; > + > + return 11; /* extreme */ > +} > + > +static int veml6070_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int *val, int *val2, long mask) > +{ > + struct veml6070_data *data = iio_priv(indio_dev); > + int ret; > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + case IIO_CHAN_INFO_PROCESSED: > + ret = veml6070_read(data); > + if (ret < 0) > + return ret; > + if (mask == IIO_CHAN_INFO_PROCESSED) > + *val = veml6070_to_uv_index(ret); > + else > + *val = ret; > + return IIO_VAL_INT; > + default: > + return -EINVAL; > + } > +} > + > +static const struct iio_info veml6070_info = { > + .read_raw = veml6070_read_raw, > + .driver_module = THIS_MODULE, > +}; > + > +static int veml6070_probe(struct i2c_client *client, > + const struct i2c_device_id *id) > +{ > + struct veml6070_data *data; > + struct iio_dev *indio_dev; > + int ret; > + > + 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->client1 = client; > + mutex_init(&data->lock); > + > + indio_dev->dev.parent = &client->dev; > + indio_dev->info = &veml6070_info; > + indio_dev->channels = veml6070_channels; > + indio_dev->num_channels = ARRAY_SIZE(veml6070_channels); > + indio_dev->name = VEML6070_DRV_NAME; > + indio_dev->modes = INDIO_DIRECT_MODE; > + > + data->client2 = i2c_new_dummy(client->adapter, VEML6070_ADDR_DATA_LSB); > + if (!data->client2) { > + dev_err(&client->dev, "i2c device for second chip address failed\n"); > + return -ENODEV; > + } > + > + data->config = VEML6070_IT_10 | VEML6070_COMMAND_RSRVD | > + VEML6070_COMMAND_SD; > + ret = i2c_smbus_write_byte(data->client1, data->config); > + if (ret < 0) > + goto fail; > + > + ret = iio_device_register(indio_dev); > + if (ret < 0) > + goto fail; > + > + return ret; > + > +fail: > + i2c_unregister_device(data->client2); > + return ret; > +} > + > +static int veml6070_remove(struct i2c_client *client) > +{ > + struct iio_dev *indio_dev = i2c_get_clientdata(client); > + struct veml6070_data *data = iio_priv(indio_dev); > + > + iio_device_unregister(indio_dev); > + i2c_unregister_device(data->client2); > + > + return 0; > +} > + > +static const struct i2c_device_id veml6070_id[] = { > + { "veml6070", 0 }, > + { } > +}; > +MODULE_DEVICE_TABLE(i2c, veml6070_id); > + > +static struct i2c_driver veml6070_driver = { > + .driver = { > + .name = VEML6070_DRV_NAME, > + }, > + .probe = veml6070_probe, > + .remove = veml6070_remove, > + .id_table = veml6070_id, > +}; > + > +module_i2c_driver(veml6070_driver); > + > +MODULE_AUTHOR("Peter Meerwald-Stadler <pmeerw@xxxxxxxxxx>"); > +MODULE_DESCRIPTION("Vishay VEML6070 UV A light sensor driver"); > +MODULE_LICENSE("GPL"); > -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
