Re: [PATCH v4 2/2] iio: light: noa1305: Add support for NOA1305
From: Jonathan Cameron
Date: Mon Aug 05 2019 - 11:57:36 EST
On Fri, 2 Aug 2019 12:42:28 +0100
Martyn Welch <martyn.welch@xxxxxxxxxxxxx> wrote:
> This driver adds the initial support for the ON Semiconductor
> NOA1305 Ambient Light Sensor.
>
> Originally written by Sergei Miroshnichenko. Found here:
> https://github.com/EmcraftSystems/linux-upstream/commit/196d6cf897e632d2cb82d45484bd7a1bfdd5b6d9
>
> Signed-off-by: Sergei M <fizik1@xxxxxxxxxx>
> Signed-off-by: Martyn Welch <martyn.welch@xxxxxxxxxxxxx>
One minor thing I'll fix up whilst applying.
Applied to the togreg branch of iio.git and pushed out as testing
to see if we missed anything!
Thanks,
Jonathan
> ---
>
> Changes:
> v2:
> - Correcting authorship and SOB.
> v3:
> - Improve register define naming.
> - Follow IIO convention of interleaving register bit definitions with
> register defintions.
> - Use proper endian swapping.
> - Process raw sensor count into Lux.
> - Avoid setting variables to zero when not needed.
> - Check return value of i2c writes.
> - Implement disabling of regulator as a devm action.
> - Remove excessive white spacing.
> v4:
> - Clean up returns
> - Remove redundant noa1305_remove()
> - Remove redundant interrupt configuration/disabling
> - Return raw value and scaling
>
> Note: Scaling added for all possible interation times to ensure the
> mechanism utilised would allow this, though chip currently
> statically configured to 800mS.
>
> drivers/iio/light/Kconfig | 10 ++
> drivers/iio/light/Makefile | 1 +
> drivers/iio/light/noa1305.c | 312 ++++++++++++++++++++++++++++++++++++
> 3 files changed, 323 insertions(+)
> create mode 100644 drivers/iio/light/noa1305.c
>
> diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
> index 954c958cfc43..d1db0ec0d0f5 100644
> --- a/drivers/iio/light/Kconfig
> +++ b/drivers/iio/light/Kconfig
> @@ -309,6 +309,16 @@ config MAX44009
> To compile this driver as a module, choose M here:
> the module will be called max44009.
>
> +config NOA1305
> + tristate "ON Semiconductor NOA1305 ambient light sensor"
> + depends on I2C
Needs to select REGMAP_I2C I think. I'll add that if it's all I find.
> + help
> + Say Y here if you want to build support for the ON Semiconductor
> + NOA1305 ambient light sensor.
> +
> + To compile this driver as a module, choose M here:
> + The module will be called noa1305.
> +
> config OPT3001
> tristate "Texas Instruments OPT3001 Light Sensor"
> depends on I2C
> diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
> index e40794fbb435..00d1f9b98f39 100644
> --- a/drivers/iio/light/Makefile
> +++ b/drivers/iio/light/Makefile
> @@ -29,6 +29,7 @@ obj-$(CONFIG_LTR501) += ltr501.o
> obj-$(CONFIG_LV0104CS) += lv0104cs.o
> obj-$(CONFIG_MAX44000) += max44000.o
> obj-$(CONFIG_MAX44009) += max44009.o
> +obj-$(CONFIG_NOA1305) += noa1305.o
> obj-$(CONFIG_OPT3001) += opt3001.o
> obj-$(CONFIG_PA12203001) += pa12203001.o
> obj-$(CONFIG_RPR0521) += rpr0521.o
> diff --git a/drivers/iio/light/noa1305.c b/drivers/iio/light/noa1305.c
> new file mode 100644
> index 000000000000..b8758aa7b32a
> --- /dev/null
> +++ b/drivers/iio/light/noa1305.c
> @@ -0,0 +1,312 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Support for ON Semiconductor NOA1305 ambient light sensor
> + *
> + * Copyright (C) 2016 Emcraft Systems
> + * Copyright (C) 2019 Collabora Ltd.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/err.h>
> +#include <linux/i2c.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
> +
> +#define NOA1305_REG_POWER_CONTROL 0x0
> +#define NOA1305_POWER_CONTROL_DOWN 0x00
> +#define NOA1305_POWER_CONTROL_ON 0x08
> +#define NOA1305_REG_RESET 0x1
> +#define NOA1305_RESET_RESET 0x10
> +#define NOA1305_REG_INTEGRATION_TIME 0x2
> +#define NOA1305_INTEGR_TIME_800MS 0x00
> +#define NOA1305_INTEGR_TIME_400MS 0x01
> +#define NOA1305_INTEGR_TIME_200MS 0x02
> +#define NOA1305_INTEGR_TIME_100MS 0x03
> +#define NOA1305_INTEGR_TIME_50MS 0x04
> +#define NOA1305_INTEGR_TIME_25MS 0x05
> +#define NOA1305_INTEGR_TIME_12_5MS 0x06
> +#define NOA1305_INTEGR_TIME_6_25MS 0x07
> +#define NOA1305_REG_INT_SELECT 0x3
> +#define NOA1305_INT_SEL_ACTIVE_HIGH 0x01
> +#define NOA1305_INT_SEL_ACTIVE_LOW 0x02
> +#define NOA1305_INT_SEL_INACTIVE 0x03
> +#define NOA1305_REG_INT_THRESH_LSB 0x4
> +#define NOA1305_REG_INT_THRESH_MSB 0x5
> +#define NOA1305_REG_ALS_DATA_LSB 0x6
> +#define NOA1305_REG_ALS_DATA_MSB 0x7
> +#define NOA1305_REG_DEVICE_ID_LSB 0x8
> +#define NOA1305_REG_DEVICE_ID_MSB 0x9
> +
> +#define NOA1305_DEVICE_ID 0x0519
> +#define NOA1305_DRIVER_NAME "noa1305"
> +
> +struct noa1305_priv {
> + struct i2c_client *client;
> + struct regmap *regmap;
> + struct regulator *vin_reg;
> +};
> +
> +static int noa1305_measure(struct noa1305_priv *priv)
> +{
> + __le16 data;
> + int ret;
> +
> + ret = regmap_bulk_read(priv->regmap, NOA1305_REG_ALS_DATA_LSB, &data,
> + 2);
> + if (ret < 0)
> + return ret;
> +
> + return le16_to_cpu(data);
> +}
> +
> +static int noa1305_scale(struct noa1305_priv *priv, int *val, int *val2)
> +{
> + int data;
> + int ret;
> +
> + ret = regmap_read(priv->regmap, NOA1305_REG_INTEGRATION_TIME, &data);
> + if (ret < 0)
> + return ret;
> +
> + /*
> + * Lux = count / (<Integration Constant> * <Integration Time>)
> + *
> + * Integration Constant = 7.7
> + * Integration Time in Seconds
> + */
> + switch (data) {
> + case NOA1305_INTEGR_TIME_800MS:
> + *val = 100;
> + *val2 = 77 * 8;
> + break;
> + case NOA1305_INTEGR_TIME_400MS:
> + *val = 100;
> + *val2 = 77 * 4;
> + case NOA1305_INTEGR_TIME_200MS:
> + *val = 100;
> + *val2 = 77 * 2;
> + break;
> + case NOA1305_INTEGR_TIME_100MS:
> + *val = 100;
> + *val2 = 77;
> + break;
> + case NOA1305_INTEGR_TIME_50MS:
> + *val = 1000;
> + *val2 = 77 * 5;
> + break;
> + case NOA1305_INTEGR_TIME_25MS:
> + *val = 10000;
> + *val2 = 77 * 25;
> + break;
> + case NOA1305_INTEGR_TIME_12_5MS:
> + *val = 100000;
> + *val2 = 77 * 125;
> + break;
> + case NOA1305_INTEGR_TIME_6_25MS:
> + *val = 1000000;
> + *val2 = 77 * 625;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + return IIO_VAL_FRACTIONAL;
> +}
> +
> +static const struct iio_chan_spec noa1305_channels[] = {
> + {
> + .type = IIO_LIGHT,
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
> + }
> +};
> +
> +static int noa1305_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2, long mask)
> +{
> + int ret = -EINVAL;
> + struct noa1305_priv *priv = iio_priv(indio_dev);
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + switch (chan->type) {
> + case IIO_LIGHT:
> + ret = noa1305_measure(priv);
> + if (ret < 0)
> + return ret;
> + *val = ret;
> + return IIO_VAL_INT;
> + default:
> + break;
> + }
> + break;
> + case IIO_CHAN_INFO_SCALE:
> + switch (chan->type) {
> + case IIO_LIGHT:
> + return noa1305_scale(priv, val, val2);
> + default:
> + break;
> + }
> + break;
> + default:
> + break;
> + }
> +
> + return ret;
> +}
> +
> +static const struct iio_info noa1305_info = {
> + .read_raw = noa1305_read_raw,
> +};
> +
> +static bool noa1305_writable_reg(struct device *dev, unsigned int reg)
> +{
> + switch (reg) {
> + case NOA1305_REG_POWER_CONTROL:
> + case NOA1305_REG_RESET:
> + case NOA1305_REG_INTEGRATION_TIME:
> + case NOA1305_REG_INT_SELECT:
> + case NOA1305_REG_INT_THRESH_LSB:
> + case NOA1305_REG_INT_THRESH_MSB:
> + return true;
> + default:
> + return false;
> + }
> +}
> +
> +static const struct regmap_config noa1305_regmap_config = {
> + .name = NOA1305_DRIVER_NAME,
> + .reg_bits = 8,
> + .val_bits = 8,
> + .max_register = NOA1305_REG_DEVICE_ID_MSB,
> + .writeable_reg = noa1305_writable_reg,
> +};
> +
> +static void noa1305_reg_remove(void *data)
> +{
> + struct noa1305_priv *priv = data;
> +
> + regulator_disable(priv->vin_reg);
> +}
> +
> +static int noa1305_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + struct noa1305_priv *priv;
> + struct iio_dev *indio_dev;
> + struct regmap *regmap;
> + __le16 data;
> + unsigned int dev_id;
> + int ret;
> +
> + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*priv));
> + if (!indio_dev)
> + return -ENOMEM;
> +
> + regmap = devm_regmap_init_i2c(client, &noa1305_regmap_config);
> + if (IS_ERR(regmap)) {
> + dev_err(&client->dev, "Regmap initialization failed.\n");
> + return PTR_ERR(regmap);
> + }
> +
> + priv = iio_priv(indio_dev);
> +
> + priv->vin_reg = devm_regulator_get(&client->dev, "vin");
> + if (IS_ERR(priv->vin_reg)) {
> + dev_err(&client->dev, "get regulator vin failed\n");
> + return PTR_ERR(priv->vin_reg);
> + }
> +
> + ret = regulator_enable(priv->vin_reg);
> + if (ret) {
> + dev_err(&client->dev, "enable regulator vin failed\n");
> + return ret;
> + }
> +
> + ret = devm_add_action_or_reset(&client->dev, noa1305_reg_remove, priv);
> + if (ret) {
> + dev_err(&client->dev, "addition of devm action failed\n");
> + return ret;
> + }
> +
> + i2c_set_clientdata(client, indio_dev);
> + priv->client = client;
> + priv->regmap = regmap;
> +
> + ret = regmap_bulk_read(regmap, NOA1305_REG_DEVICE_ID_LSB, &data, 2);
> + if (ret < 0) {
> + dev_err(&client->dev, "ID reading failed: %d\n", ret);
> + return ret;
> + }
> +
> + dev_id = le16_to_cpu(data);
> + if (dev_id != NOA1305_DEVICE_ID) {
> + dev_err(&client->dev, "Unknown device ID: 0x%x\n", dev_id);
> + return -ENODEV;
> + }
> +
> + ret = regmap_write(regmap, NOA1305_REG_POWER_CONTROL,
> + NOA1305_POWER_CONTROL_ON);
> + if (ret < 0) {
> + dev_err(&client->dev, "Enabling power control failed\n");
> + return ret;
> + }
> +
> + ret = regmap_write(regmap, NOA1305_REG_RESET, NOA1305_RESET_RESET);
> + if (ret < 0) {
> + dev_err(&client->dev, "Device reset failed\n");
> + return ret;
> + }
> +
> + ret = regmap_write(regmap, NOA1305_REG_INTEGRATION_TIME,
> + NOA1305_INTEGR_TIME_800MS);
> + if (ret < 0) {
> + dev_err(&client->dev, "Setting integration time failed\n");
> + return ret;
> + }
> +
> + indio_dev->dev.parent = &client->dev;
> + indio_dev->info = &noa1305_info;
> + indio_dev->channels = noa1305_channels;
> + indio_dev->num_channels = ARRAY_SIZE(noa1305_channels);
> + indio_dev->name = NOA1305_DRIVER_NAME;
> + indio_dev->modes = INDIO_DIRECT_MODE;
> +
> + ret = devm_iio_device_register(&client->dev, indio_dev);
> + if (ret)
> + dev_err(&client->dev, "registering device failed\n");
> +
> + return ret;
> +}
> +
> +static const struct of_device_id noa1305_of_match[] = {
> + { .compatible = "onnn,noa1305" },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, noa1305_of_match);
> +
> +static const struct i2c_device_id noa1305_ids[] = {
> + { "noa1305", 0 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(i2c, noa1305_id);
> +
> +static struct i2c_driver noa1305_driver = {
> + .driver = {
> + .name = NOA1305_DRIVER_NAME,
> + .of_match_table = noa1305_of_match,
> + },
> + .probe = noa1305_probe,
> + .id_table = noa1305_ids,
> +};
> +
> +module_i2c_driver(noa1305_driver);
> +
> +MODULE_AUTHOR("Sergei Miroshnichenko <sergeimir@xxxxxxxxxxx>");
> +MODULE_AUTHOR("Martyn Welch <martyn.welch@xxxxxxxxxxxxx");
> +MODULE_DESCRIPTION("ON Semiconductor NOA1305 ambient light sensor");
> +MODULE_LICENSE("GPL");