Re: [PATCH v7 5/5] iio: light: Add support for APDS9306 Light Sensor

Andy Shevchenko
2024-02-26T14:12:31Z

On Sun, Feb 18, 2024 at 04:18:26PM +1030, Subhajit Ghosh wrote:
> Driver support for Avago (Broadcom) APDS9306 Ambient Light Sensor.
> It has two channels - ALS and CLEAR. The ALS (Ambient Light Sensor)
> channel approximates the response of the human-eye providing direct
> read out where the output count is proportional to ambient light levels.
> It is internally temperature compensated and rejects 50Hz and 60Hz flicker
> caused by artificial light sources. Hardware interrupt configuration is
> optional. It is a low power device with 20 bit resolution and has
> configurable adaptive interrupt mode and interrupt persistence mode.
> The device also features inbuilt hardware gain, multiple integration time
> selection options and sampling frequency selection options.
>
> This driver also uses the IIO GTS (Gain Time Scale) Helpers Namespace for
> Scales, Gains and Integration time implementation.

...

> +/*
> + * Available scales with gain 1x - 18x, timings 3.125, 25, 50, 100, 200, 400 mS

"mS" --> "ms."

> + * Time impacts to gain: 1x, 8x, 16x, 32x, 64x, 128x
> + */

...

> + /*
> + * If this function runs parallel with the interrupt handler, either
> + * this reads and clears the status registers or the interrupt handler
> + * does. The interrupt handler sets a flag for read data available
> + * in our private structure which we read here.
> + */
> + ret = regmap_read_poll_timeout(data->regmap, APDS9306_MAIN_STATUS_REG,
> + status, data->read_data_available ||
> + (status & (APDS9306_ALS_DATA_STAT_MASK |
> + APDS9306_ALS_INT_STAT_MASK)),
> + APDS9306_ALS_READ_DATA_DELAY_US, delay * 2);

> +

Redundant blank line

> + if (ret)
> + return ret;

...

> +static int apds9306_init_iio_gts(struct apds9306_data *data)
> +{
> + int i, ret, part_id;
> +
> + ret = regmap_read(data->regmap, APDS9306_PART_ID_REG, &part_id);
> + if (ret)
> + return ret;
> +
> + for (i = 0; i < ARRAY_SIZE(apds9306_gts_mul); i++)
> + if (part_id == apds9306_gts_mul[i].part_id)
> + break;
> +
> + if (i == ARRAY_SIZE(apds9306_gts_mul))
> + return -ENXIO;

Strange choice of the error code, why not (one of) -ENOENT / -ENODATA ?

> + return devm_iio_init_iio_gts(data->dev,
> + apds9306_gts_mul[i].max_scale_int,
> + apds9306_gts_mul[i].max_scale_nano,
> + apds9306_gains, ARRAY_SIZE(apds9306_gains),
> + apds9306_itimes, ARRAY_SIZE(apds9306_itimes),
> + &data->gts);

> +
> + return -ENXIO;

Dead code.

> +}

...

Jonathan, are you going to apply this and addressing comments at the same time?
Or should it be another version?

--
With Best Regards,
Andy Shevchenko