On 22/03/16 16:08, Ludovic Desroches wrote:
> Add signed differential channels and update the voltage scale for
> differential conversions.
>
> Signed-off-by: Ludovic Desroches <ludovic.desroc...@atmel.com>
Looks good to me.
Applied to the togreg branch of iio.git - initially pushed out as testing
etc etc.
Jonathan
> ---
>
> This patch is based on:
> iio:adc:at91-sama5d2: fix identation
> iio:adc:at91-sama5d2: fix typo
>
> drivers/iio/adc/at91-sama5d2_adc.c | 71
> ++++++++++++++++++++++++++++++--------
> 1 file changed, 56 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/iio/adc/at91-sama5d2_adc.c
> b/drivers/iio/adc/at91-sama5d2_adc.c
> index 01ba106..07adb10 100644
> --- a/drivers/iio/adc/at91-sama5d2_adc.c
> +++ b/drivers/iio/adc/at91-sama5d2_adc.c
> @@ -113,8 +113,11 @@
> #define AT91_SAMA5D2_CWR 0x44
> /* Channel Gain Register */
> #define AT91_SAMA5D2_CGR 0x48
> +
Ever so slight gripe here as this is unconnected to this patch so should have
been in a trivial additional patch...
> /* Channel Offset Register */
> #define AT91_SAMA5D2_COR 0x4c
> +#define AT91_SAMA5D2_COR_DIFF_OFFSET 16
> +
> /* Channel Data Register 0 */
> #define AT91_SAMA5D2_CDR0 0x50
> /* Analog Control Register */
> @@ -142,7 +145,7 @@
> /* Version Register */
> #define AT91_SAMA5D2_VERSION 0xfc
>
> -#define AT91_SAMA5D2_CHAN(num, addr) \
> +#define AT91_SAMA5D2_CHAN_SINGLE(num, addr) \
> { \
> .type = IIO_VOLTAGE, \
> .channel = num, \
> @@ -158,6 +161,24 @@
> .indexed = 1, \
> }
>
> +#define AT91_SAMA5D2_CHAN_DIFF(num, num2, addr)
> \
> + { \
> + .type = IIO_VOLTAGE, \
> + .differential = 1, \
> + .channel = num, \
> + .channel2 = num2, \
> + .address = addr, \
> + .scan_type = { \
> + .sign = 's', \
> + .realbits = 12, \
> + }, \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
> + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
> + .datasheet_name = "CH"#num"-CH"#num2, \
> + .indexed = 1, \
> + }
> +
> #define at91_adc_readl(st, reg) readl_relaxed(st->base + reg)
> #define at91_adc_writel(st, reg, val) writel_relaxed(val, st->base +
> reg)
>
> @@ -187,18 +208,24 @@ struct at91_adc_state {
> };
>
> static const struct iio_chan_spec at91_adc_channels[] = {
> - AT91_SAMA5D2_CHAN(0, 0x50),
> - AT91_SAMA5D2_CHAN(1, 0x54),
> - AT91_SAMA5D2_CHAN(2, 0x58),
> - AT91_SAMA5D2_CHAN(3, 0x5c),
> - AT91_SAMA5D2_CHAN(4, 0x60),
> - AT91_SAMA5D2_CHAN(5, 0x64),
> - AT91_SAMA5D2_CHAN(6, 0x68),
> - AT91_SAMA5D2_CHAN(7, 0x6c),
> - AT91_SAMA5D2_CHAN(8, 0x70),
> - AT91_SAMA5D2_CHAN(9, 0x74),
> - AT91_SAMA5D2_CHAN(10, 0x78),
> - AT91_SAMA5D2_CHAN(11, 0x7c),
> + AT91_SAMA5D2_CHAN_SINGLE(0, 0x50),
> + AT91_SAMA5D2_CHAN_SINGLE(1, 0x54),
> + AT91_SAMA5D2_CHAN_SINGLE(2, 0x58),
> + AT91_SAMA5D2_CHAN_SINGLE(3, 0x5c),
> + AT91_SAMA5D2_CHAN_SINGLE(4, 0x60),
> + AT91_SAMA5D2_CHAN_SINGLE(5, 0x64),
> + AT91_SAMA5D2_CHAN_SINGLE(6, 0x68),
> + AT91_SAMA5D2_CHAN_SINGLE(7, 0x6c),
> + AT91_SAMA5D2_CHAN_SINGLE(8, 0x70),
> + AT91_SAMA5D2_CHAN_SINGLE(9, 0x74),
> + AT91_SAMA5D2_CHAN_SINGLE(10, 0x78),
> + AT91_SAMA5D2_CHAN_SINGLE(11, 0x7c),
> + AT91_SAMA5D2_CHAN_DIFF(0, 1, 0x50),
> + AT91_SAMA5D2_CHAN_DIFF(2, 3, 0x58),
> + AT91_SAMA5D2_CHAN_DIFF(4, 5, 0x60),
> + AT91_SAMA5D2_CHAN_DIFF(6, 7, 0x68),
> + AT91_SAMA5D2_CHAN_DIFF(8, 9, 0x70),
> + AT91_SAMA5D2_CHAN_DIFF(10, 11, 0x78),
> };
>
> static unsigned at91_adc_startup_time(unsigned startup_time_min,
> @@ -281,6 +308,7 @@ static int at91_adc_read_raw(struct iio_dev *indio_dev,
> int *val, int *val2, long mask)
> {
> struct at91_adc_state *st = iio_priv(indio_dev);
> + u32 cor = 0;
> int ret;
>
> switch (mask) {
> @@ -289,6 +317,11 @@ static int at91_adc_read_raw(struct iio_dev *indio_dev,
>
> st->chan = chan;
>
> + if (chan->differential)
> + cor = (BIT(chan->channel) | BIT(chan->channel2)) <<
> + AT91_SAMA5D2_COR_DIFF_OFFSET;
> +
> + at91_adc_writel(st, AT91_SAMA5D2_COR, cor);
> at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel));
> at91_adc_writel(st, AT91_SAMA5D2_IER, BIT(chan->channel));
> at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_START);
> @@ -301,6 +334,8 @@ static int at91_adc_read_raw(struct iio_dev *indio_dev,
>
> if (ret > 0) {
> *val = st->conversion_value;
> + if (chan->scan_type.sign == 's')
> + *val = sign_extend32(*val, 11);
> ret = IIO_VAL_INT;
> st->conversion_done = false;
> }
> @@ -313,6 +348,8 @@ static int at91_adc_read_raw(struct iio_dev *indio_dev,
>
> case IIO_CHAN_INFO_SCALE:
> *val = st->vref_uv / 1000;
> + if (chan->differential)
> + *val *= 2;
> *val2 = chan->scan_type.realbits;
> return IIO_VAL_FRACTIONAL_LOG2;
>
> @@ -447,8 +484,12 @@ static int at91_adc_probe(struct platform_device *pdev)
>
> at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_SWRST);
> at91_adc_writel(st, AT91_SAMA5D2_IDR, 0xffffffff);
> - /* Transfer field must be set to 2 according to the datasheet. */
> - at91_adc_writel(st, AT91_SAMA5D2_MR, AT91_SAMA5D2_MR_TRANSFER(2));
> + /*
> + * Transfer field must be set to 2 according to the datasheet and
> + * allows different analog settings for each channel.
> + */
> + at91_adc_writel(st, AT91_SAMA5D2_MR,
> + AT91_SAMA5D2_MR_TRANSFER(2) | AT91_SAMA5D2_MR_ANACH);
>
> at91_adc_setup_samp_freq(st, st->soc_info.min_sample_rate);
>
>
