Re: [PATCH v4 1/6] iio: accel: add support for FXLS8962AF/FXLS8964AF accelerometers

[Tomas Melin <tomas.melin@vaisala.com>]

Hi,

few comments inline below.

Thanks,

Tomas


On 4/29/21 3:28 PM, Sean Nyekjaer wrote:
> Add basic support for NXP FXLS8962AF/FXLS8964AF Automotive
> accelerometers.
> It will allow setting up scale/gain and reading x,y,z
> axis.
>
> Datasheet: https://www.nxp.com/docs/en/data-sheet/FXLS8962AF.pdf
> Datasheet: https://www.nxp.com/docs/en/data-sheet/FXLS8964AF.pdf
> Signed-off-by: Sean Nyekjaer <sean@geanix.com>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> ---
> Changes for v2:
>   - Addressed Kconfig comments
>   - Using regmap_read_poll_timeout()
>   - Addresed comments from Andy and Jonathan
>
> Changes for v3:
>   - fixed Kconfig ordering
>   - read INT_STATUS after reset, to ensure the device is ready
>   - fixed a few xmas trees
>   - added datasheet tags
>
> Changes for v4:
>   - reworked read_raw -> fxls8962af_get_out, so we will skip the claim
>     part.
>   - Removed the drdy check, worstcase data will be 1,28s/0.781Hz old.
>
>   drivers/iio/accel/Kconfig           |  27 ++
>   drivers/iio/accel/Makefile          |   3 +
>   drivers/iio/accel/fxls8962af-core.c | 563 ++++++++++++++++++++++++++++
>   drivers/iio/accel/fxls8962af-i2c.c  |  57 +++
>   drivers/iio/accel/fxls8962af-spi.c  |  57 +++
>   drivers/iio/accel/fxls8962af.h      |  22 ++
>   6 files changed, 729 insertions(+)
>   create mode 100644 drivers/iio/accel/fxls8962af-core.c
>   create mode 100644 drivers/iio/accel/fxls8962af-i2c.c
>   create mode 100644 drivers/iio/accel/fxls8962af-spi.c
>   create mode 100644 drivers/iio/accel/fxls8962af.h
>
> diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
> index 2e0c62c39155..7317d839ca1a 100644
> --- a/drivers/iio/accel/Kconfig
> +++ b/drivers/iio/accel/Kconfig
> @@ -208,6 +208,33 @@ config DMARD10
>   	  Choosing M will build the driver as a module. If so, the module
>   	  will be called dmard10.
>   

...

> +}
> +
> +static int fxls8962af_power_off(struct fxls8962af_data *data)
> +{
> +	struct device *dev = regmap_get_device(data->regmap);
> +	int ret;
> +
> +	pm_runtime_mark_last_busy(dev);
> +	ret = pm_runtime_put_autosuspend(dev);
> +

could drop extra empty line here.

> +	if (ret < 0) {
> +		dev_err(dev, "failed to power off\n");
> +	}
> +
> +	return ret;
> +}
...
> +
> +static int fxls8962af_reset(struct fxls8962af_data *data)
> +{
> +	struct device *dev = regmap_get_device(data->regmap);
> +	unsigned int reg;
> +	int ret;
> +
> +	ret = regmap_update_bits(data->regmap, FXLS8962AF_SENS_CONFIG1,
> +				 FXLS8962AF_SENS_CONFIG1_RST,
> +				 FXLS8962AF_SENS_CONFIG1_RST);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* TBOOT1, TBOOT2, specifies we have to wait between 1 - 17.7ms */
> +	ret = regmap_read_poll_timeout(data->regmap, FXLS8962AF_INT_STATUS, reg,
> +			(reg & FXLS8962AF_INT_STATUS_SRC_BOOT), 1000, 18000);
> +	if (ret)
> +		dev_err(dev, "reset timeout, int_status = 0x%x\n", reg);

Should check for -ETIMEDOUT here rather than generic error? and handle 
both cases.

> +
> +	return ret;
> +}
> +
> +static void fxls8962af_regulator_disable(void *data_ptr)
> +{
> +	struct fxls8962af_data *data = data_ptr;
> +
> +	regulator_disable(data->vdd_reg);
> +}
> +
> +static void fxls8962af_pm_disable(void *dev_ptr)
> +{
> +	struct device *dev = dev_ptr;
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +
> +	pm_runtime_disable(dev);
> +	pm_runtime_set_suspended(dev);
> +	pm_runtime_put_noidle(dev);
> +
> +	fxls8962af_standby(iio_priv(indio_dev));
> +}
> +
> +int fxls8962af_core_probe(struct device *dev, struct regmap *regmap, int irq)
> +{
> +	struct fxls8962af_data *data;
> +	struct iio_dev *indio_dev;
> +	unsigned int reg;
> +	int ret, i;
> +
> +	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
> +	if (!indio_dev)
> +		return -ENOMEM;
> +
> +	data = iio_priv(indio_dev);
> +	dev_set_drvdata(dev, indio_dev);
> +	data->regmap = regmap;
> +
> +	ret = iio_read_mount_matrix(dev, "mount-matrix", &data->orientation);
> +	if (ret)
> +		return ret;
> +
> +	data->vdd_reg = devm_regulator_get(dev, "vdd");
> +	if (IS_ERR(data->vdd_reg))
> +		return dev_err_probe(dev, PTR_ERR(data->vdd_reg),
> +				     "Failed to get vdd regulator\n");
> +
> +	ret = regulator_enable(data->vdd_reg);
> +	if (ret) {
> +		dev_err(dev, "Failed to enable vdd regulator: %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = devm_add_action_or_reset(dev, fxls8962af_regulator_disable, data);
> +	if (ret)
> +		return ret;
> +
> +	ret = regmap_read(data->regmap, FXLS8962AF_WHO_AM_I, &reg);
> +	if (ret < 0)
> +		return ret;
Could consider to use if (ret) consistently throughout this function?
> +
> +	for (i = 0; i < ARRAY_SIZE(fxls_chip_info_table); i++) {
> +		if (fxls_chip_info_table[i].chip_id == reg) {
> +			data->chip_info = &fxls_chip_info_table[i];
> +			break;
> +		}
> +	}
> +	if (i == ARRAY_SIZE(fxls_chip_info_table)) {
> +		dev_err(dev, "failed to match device in table\n");
> +		return -ENXIO;
> +	}
> +
> +	indio_dev->channels = data->chip_info->channels;
> +	indio_dev->num_channels = data->chip_info->num_channels;
> +	indio_dev->name = data->chip_info->name;
> +	indio_dev->info = &fxls8962af_info;
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +
> +	ret = fxls8962af_reset(data);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = pm_runtime_set_active(dev);
> +	if (ret < 0)
> +		return ret;
> +
> +	pm_runtime_enable(dev);
> +	pm_runtime_set_autosuspend_delay(dev, FXLS8962AF_AUTO_SUSPEND_DELAY_MS);
> +	pm_runtime_use_autosuspend(dev);
> +
> +	ret = devm_add_action_or_reset(dev, fxls8962af_pm_disable, dev);
> +	if (ret)
> +		return ret;
> +
> +	return devm_iio_device_register(dev, indio_dev);
> +}
> +EXPORT_SYMBOL_GPL(fxls8962af_core_probe);
> +
> +