Re: [PATCH 05/11] staging:iio:ad7793: Rework platform data

[Jonathan Cameron <jic23@kernel.org>]

On 11/21/2012 04:27 PM, Lars-Peter Clausen wrote:
> Currently the platform data for the ad7793 consist just out of the raw default
> register settings. This has some downsides, for one we actually don't want to
> make all bits configurable and secondly not all register settings are actually
> valid. This patch exposes all the options which should be configurable via
> platform data as induvidual platform data struct fields. This also allows us to
> document the different settings via proper kernel doc.
>
Good to see this cleared up.

> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
added (as have previous patches to togreg branch of iio.git)


> ---
>  drivers/staging/iio/adc/ad7793.c |  25 +++++++--
>  drivers/staging/iio/adc/ad7793.h | 107 +++++++++++++++++++++++++++++++++++++--
>  2 files changed, 123 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/staging/iio/adc/ad7793.c b/drivers/staging/iio/adc/ad7793.c
> index 028473a..8b08693 100644
> --- a/drivers/staging/iio/adc/ad7793.c
> +++ b/drivers/staging/iio/adc/ad7793.c
> @@ -118,6 +118,12 @@ static int ad7793_setup(struct iio_dev *indio_dev,
>  	unsigned long long scale_uv;
>  	u32 id;
>
> +	if ((pdata->current_source_direction == AD7793_IEXEC1_IEXEC2_IOUT1 ||
> +		pdata->current_source_direction == AD7793_IEXEC1_IEXEC2_IOUT2) &&
> +		((pdata->exitation_current != AD7793_IX_10uA) &&
> +		(pdata->exitation_current != AD7793_IX_210uA)))
> +		return -EINVAL;
> +
>  	/* reset the serial interface */
>  	ret = spi_write(st->sd.spi, (u8 *)&ret, sizeof(ret));
>  	if (ret < 0)
> @@ -136,8 +142,18 @@ static int ad7793_setup(struct iio_dev *indio_dev,
>  		goto out;
>  	}
>
> -	st->mode = pdata->mode;
> -	st->conf = pdata->conf;
> +	st->mode = AD7793_MODE_RATE(1);
> +	st->mode |= AD7793_MODE_CLKSRC(pdata->clock_src);
> +	st->conf = AD7793_CONF_REFSEL(pdata->refsel);
> +	st->conf |= AD7793_CONF_VBIAS(pdata->bias_voltage);
> +	if (pdata->buffered)
> +		st->conf |= AD7793_CONF_BUF;
> +	if (pdata->boost_enable)
> +		st->conf |= AD7793_CONF_BOOST;
> +	if (pdata->burnout_current)
> +		st->conf |= AD7793_CONF_BO_EN;
> +	if (pdata->unipolar)
> +		st->conf |= AD7793_CONF_UNIPOLAR;
>
>  	ret = ad7793_set_mode(&st->sd, AD_SD_MODE_IDLE);
>  	if (ret)
> @@ -147,8 +163,9 @@ static int ad7793_setup(struct iio_dev *indio_dev,
>  	if (ret)
>  		goto out;
>
> -	ret = ad_sd_write_reg(&st->sd, AD7793_REG_IO,
> -			       sizeof(pdata->io), pdata->io);
> +	ret = ad_sd_write_reg(&st->sd, AD7793_REG_IO, 1,
> +				   pdata->exitation_current |
> +			       (pdata->current_source_direction << 2));
>  	if (ret)
>  		goto out;
>
> diff --git a/drivers/staging/iio/adc/ad7793.h b/drivers/staging/iio/adc/ad7793.h
> index 8fdd450..9e90590 100644
> --- a/drivers/staging/iio/adc/ad7793.h
> +++ b/drivers/staging/iio/adc/ad7793.h
> @@ -68,7 +68,7 @@
>  #define AD7793_CONF_UNIPOLAR	(1 << 12) /* Unipolar/Bipolar Enable */
>  #define AD7793_CONF_BOOST	(1 << 11) /* Boost Enable */
>  #define AD7793_CONF_GAIN(x)	(((x) & 0x7) << 8) /* Gain Select */
> -#define AD7793_CONF_REFSEL	(1 << 7) /* INT/EXT Reference Select */
> +#define AD7793_CONF_REFSEL(x)	((x) << 6) /* INT/EXT Reference Select */
>  #define AD7793_CONF_BUF		(1 << 4) /* Buffered Mode Enable */
>  #define AD7793_CONF_CHAN(x)	((x) & 0xf) /* Channel select */
>  #define AD7793_CONF_CHAN_MASK	0xf /* Channel select mask */
> @@ -105,11 +105,108 @@
>  #define AD7793_IO_IXCEN_210uA	(2 << 0) /* Excitation Current 210uA */
>  #define AD7793_IO_IXCEN_1mA	(3 << 0) /* Excitation Current 1mA */
>
> +/**
> + * enum ad7793_clock_source - AD7793 clock source selection
> + * @AD7793_CLK_SRC_INT: Internal 64 kHz clock, not available at the CLK pin.
> + * @AD7793_CLK_SRC_INT_CO: Internal 64 kHz clock, available at the CLK pin.
> + * @AD7793_CLK_SRC_EXT: Use external clock.
> + * @AD7793_CLK_SRC_EXT_DIV2: Use external clock divided by 2.
> + */
> +enum ad7793_clock_source {
> +	AD7793_CLK_SRC_INT,
> +	AD7793_CLK_SRC_INT_CO,
> +	AD7793_CLK_SRC_EXT,
> +	AD7793_CLK_SRC_EXT_DIV2,
> +};
> +
> +/**
> + * enum ad7793_bias_voltage - AD7793 bias voltage selection
> + * @AD7793_BIAS_VOLTAGE_DISABLED: Bias voltage generator disabled
> + * @AD7793_BIAS_VOLTAGE_AIN1: Bias voltage connected to AIN1(-).
> + * @AD7793_BIAS_VOLTAGE_AIN2: Bias voltage connected to AIN2(-).
> + * @AD7793_BIAS_VOLTAGE_AIN3: Bias voltage connected to AIN3(-).
> + *	Only valid for AD7795/AD7796.
> + */
> +enum ad7793_bias_voltage {
> +	AD7793_BIAS_VOLTAGE_DISABLED,
> +	AD7793_BIAS_VOLTAGE_AIN1,
> +	AD7793_BIAS_VOLTAGE_AIN2,
> +	AD7793_BIAS_VOLTAGE_AIN3,
> +};
> +
> +/**
> + * enum ad7793_refsel - AD7793 reference voltage selection
> + * @AD7793_REFSEL_REFIN1: External reference applied between REFIN1(+)
> + *	and REFIN1(-).
> + * @AD7793_REFSEL_REFIN2: External reference applied between REFIN2(+) and
> + *	and REFIN1(-). Only valid for AD7795/AD7796.
> + * @AD7793_REFSEL_INTERNAL: Internal 1.17 V reference.
> + */
> +enum ad7793_refsel {
> +	AD7793_REFSEL_REFIN1 = 0,
> +	AD7793_REFSEL_REFIN2 = 1,
> +	AD7793_REFSEL_INTERNAL = 2,
> +};
> +
> +/**
> + * enum ad7793_current_source_direction - AD7793 excitation current direction
> + * @AD7793_IEXEC1_IOUT1_IEXEC2_IOUT2: Current source IEXC1 connected to pin
> + *	IOUT1, current source IEXC2 connected to pin IOUT2.
> + * @AD7793_IEXEC1_IOUT2_IEXEC2_IOUT1: Current source IEXC2 connected to pin
> + *	IOUT1, current source IEXC1 connected to pin IOUT2.
> + * @AD7793_IEXEC1_IEXEC2_IOUT1: Both current sources connected to pin IOUT1.
> + *	Only valid when the current sources are set to 10 uA or 210 uA.
> + * @AD7793_IEXEC1_IEXEC2_IOUT2: Both current sources connected to Pin IOUT2.
> + *	Only valid when the current ources are set to 10 uA or 210 uA.
> + */
> +enum ad7793_current_source_direction {
> +	AD7793_IEXEC1_IOUT1_IEXEC2_IOUT2 = 0,
> +	AD7793_IEXEC1_IOUT2_IEXEC2_IOUT1 = 1,
> +	AD7793_IEXEC1_IEXEC2_IOUT1 = 2,
> +	AD7793_IEXEC1_IEXEC2_IOUT2 = 3,
> +};
> +
> +/**
> + * enum ad7793_excitation_current - AD7793 excitation current selection
> + * @AD7793_IX_DISABLED: Excitation current Disabled.
> + * @AD7793_IX_10uA: Enable 10 micro-ampere excitation current.
> + * @AD7793_IX_210uA: Enable 210 micro-ampere excitation current.
> + * @AD7793_IX_1mA: Enable 1 milli-Ampere excitation current.
> + */
> +enum ad7793_excitation_current {
> +	AD7793_IX_DISABLED = 0,
> +	AD7793_IX_10uA = 1,
> +	AD7793_IX_210uA = 2,
> +	AD7793_IX_1mA = 3,
> +};
> +
> +/**
> + * struct ad7793_platform_data - AD7793 platform data
> + * @vref_mv: Reference voltage in milli-Volt
> + * @clock_src: Clock source selection
> + * @burnout_current: If set to true the 100nA burnout current is enabled.
> + * @boost_enable: Enable boost for the bias voltage generator.
> + * @buffered: If set to true configure the device for buffered input mode.
> + * @unipolar: If set to true sample in unipolar mode, if set to false sample in
> + *		bipolar mode.
> + * @refsel: Reference voltage selection
> + * @bias_voltage: Bias voltage selection
> + * @exitation_current: Excitation current selection
> + * @current_source_direction: Excitation current direction selection
> + */
>  struct ad7793_platform_data {
> -	u16			vref_mv;
> -	u16			mode;
> -	u16			conf;
> -	u8			io;
> +	u16 vref_mv;
> +
> +	enum ad7793_clock_source clock_src;
> +	bool burnout_current;
> +	bool boost_enable;
> +	bool buffered;
> +	bool unipolar;
> +
> +	enum ad7793_refsel refsel;
> +	enum ad7793_bias_voltage bias_voltage;
> +	enum ad7793_excitation_current exitation_current;
> +	enum ad7793_current_source_direction current_source_direction;
>  };
>
>  #endif /* IIO_ADC_AD7793_H_ */
>