The current driver supports only parts with 2 channels. In order to prepare the support of new compatible ADCs with more channels, this commit: - defines MAX_NUM_CHANNEL to specify the maximum number of channels currently supported by the driver - adds available_scan_mask member in ad7380_chip_info structure - fixes spi xfer struct len depending on number of channels - fixes scan_data.raw buffer size to handle more channels - adds a timing specifications structure in ad7380_chip_info structure Signed-off-by: Julien Stephan <jstephan@xxxxxxxxxxxx> --- drivers/iio/adc/ad7380.c | 42 ++++++++++++++++++++++++++++++++---------- 1 file changed, 32 insertions(+), 10 deletions(-) diff --git a/drivers/iio/adc/ad7380.c b/drivers/iio/adc/ad7380.c index 996ca83feaed..3aca41ce9a14 100644 --- a/drivers/iio/adc/ad7380.c +++ b/drivers/iio/adc/ad7380.c @@ -29,6 +29,7 @@ #include <linux/iio/trigger_consumer.h> #include <linux/iio/triggered_buffer.h> +#define MAX_NUM_CHANNELS 2 /* 2.5V internal reference voltage */ #define AD7380_INTERNAL_REF_MV 2500 @@ -65,12 +66,19 @@ #define AD7380_ALERT_LOW_TH GENMASK(11, 0) #define AD7380_ALERT_HIGH_TH GENMASK(11, 0) +#define T_CONVERT_NS 190 /* conversion time */ +struct ad7380_timing_specs { + const unsigned int t_csh_ns; /* CS minimum high time */ +}; + struct ad7380_chip_info { const char *name; const struct iio_chan_spec *channels; unsigned int num_channels; const char * const *vcm_supplies; unsigned int num_vcm_supplies; + const unsigned long *available_scan_masks; + const struct ad7380_timing_specs *timing_specs; }; #define AD7380_CHANNEL(index, bits, diff) { \ @@ -115,16 +123,24 @@ static const unsigned long ad7380_2_channel_scan_masks[] = { 0 }; +static const struct ad7380_timing_specs ad7380_timing = { + .t_csh_ns = 10, +}; + static const struct ad7380_chip_info ad7380_chip_info = { .name = "ad7380", .channels = ad7380_channels, .num_channels = ARRAY_SIZE(ad7380_channels), + .available_scan_masks = ad7380_2_channel_scan_masks, + .timing_specs = &ad7380_timing, }; static const struct ad7380_chip_info ad7381_chip_info = { .name = "ad7381", .channels = ad7381_channels, .num_channels = ARRAY_SIZE(ad7381_channels), + .available_scan_masks = ad7380_2_channel_scan_masks, + .timing_specs = &ad7380_timing, }; static const struct ad7380_chip_info ad7383_chip_info = { @@ -133,6 +149,8 @@ static const struct ad7380_chip_info ad7383_chip_info = { .num_channels = ARRAY_SIZE(ad7383_channels), .vcm_supplies = ad7380_2_channel_vcm_supplies, .num_vcm_supplies = ARRAY_SIZE(ad7380_2_channel_vcm_supplies), + .available_scan_masks = ad7380_2_channel_scan_masks, + .timing_specs = &ad7380_timing, }; static const struct ad7380_chip_info ad7384_chip_info = { @@ -141,6 +159,8 @@ static const struct ad7380_chip_info ad7384_chip_info = { .num_channels = ARRAY_SIZE(ad7384_channels), .vcm_supplies = ad7380_2_channel_vcm_supplies, .num_vcm_supplies = ARRAY_SIZE(ad7380_2_channel_vcm_supplies), + .available_scan_masks = ad7380_2_channel_scan_masks, + .timing_specs = &ad7380_timing, }; struct ad7380_state { @@ -148,15 +168,15 @@ struct ad7380_state { struct spi_device *spi; struct regmap *regmap; unsigned int vref_mv; - unsigned int vcm_mv[2]; + unsigned int vcm_mv[MAX_NUM_CHANNELS]; /* * DMA (thus cache coherency maintenance) requires the * transfer buffers to live in their own cache lines. - * Make the buffer large enough for 2 16-bit samples and one 64-bit + * Make the buffer large enough for MAX_NUM_CHANNELS 16-bit samples and one 64-bit * aligned 64 bit timestamp. */ struct { - u16 raw[2]; + u16 raw[MAX_NUM_CHANNELS]; s64 ts __aligned(8); } scan_data __aligned(IIO_DMA_MINALIGN); @@ -194,7 +214,7 @@ static int ad7380_regmap_reg_read(void *context, unsigned int reg, .tx_buf = &st->tx, .cs_change = 1, .cs_change_delay = { - .value = 10, /* t[CSH] */ + .value = st->chip_info->timing_specs->t_csh_ns, .unit = SPI_DELAY_UNIT_NSECS, }, }, { @@ -255,7 +275,8 @@ static irqreturn_t ad7380_trigger_handler(int irq, void *p) struct ad7380_state *st = iio_priv(indio_dev); struct spi_transfer xfer = { .bits_per_word = st->chip_info->channels[0].scan_type.realbits, - .len = 4, + .len = (st->chip_info->num_channels - 1) * + ((st->chip_info->channels->scan_type.storagebits > 16) ? 4 : 2), .rx_buf = st->scan_data.raw, }; int ret; @@ -282,21 +303,22 @@ static int ad7380_read_direct(struct ad7380_state *st, .speed_hz = AD7380_REG_WR_SPEED_HZ, .bits_per_word = chan->scan_type.realbits, .delay = { - .value = 190, /* t[CONVERT] */ + .value = T_CONVERT_NS, .unit = SPI_DELAY_UNIT_NSECS, }, .cs_change = 1, .cs_change_delay = { - .value = 10, /* t[CSH] */ + .value = st->chip_info->timing_specs->t_csh_ns, .unit = SPI_DELAY_UNIT_NSECS, }, }, - /* then read both channels */ + /* then read all channels */ { .speed_hz = AD7380_REG_WR_SPEED_HZ, .bits_per_word = chan->scan_type.realbits, .rx_buf = st->scan_data.raw, - .len = 4, + .len = (st->chip_info->num_channels - 1) * + ((chan->scan_type.storagebits > 16) ? 4 : 2), }, }; int ret; @@ -472,7 +494,7 @@ static int ad7380_probe(struct spi_device *spi) indio_dev->name = st->chip_info->name; indio_dev->info = &ad7380_info; indio_dev->modes = INDIO_DIRECT_MODE; - indio_dev->available_scan_masks = ad7380_2_channel_scan_masks; + indio_dev->available_scan_masks = st->chip_info->available_scan_masks; ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev, iio_pollfunc_store_time, -- 2.44.0