diff options
Diffstat (limited to 'drivers/iio/adc/ad7476.c')
| -rw-r--r-- | drivers/iio/adc/ad7476.c | 199 |
1 files changed, 155 insertions, 44 deletions
diff --git a/drivers/iio/adc/ad7476.c b/drivers/iio/adc/ad7476.c index 76747488044b..94776f696290 100644 --- a/drivers/iio/adc/ad7476.c +++ b/drivers/iio/adc/ad7476.c @@ -12,9 +12,11 @@ #include <linux/sysfs.h> #include <linux/spi/spi.h> #include <linux/regulator/consumer.h> +#include <linux/gpio/consumer.h> #include <linux/err.h> #include <linux/module.h> #include <linux/bitops.h> +#include <linux/delay.h> #include <linux/iio/iio.h> #include <linux/iio/sysfs.h> @@ -27,33 +29,41 @@ struct ad7476_state; struct ad7476_chip_info { unsigned int int_vref_uv; struct iio_chan_spec channel[2]; + /* channels used when convst gpio is defined */ + struct iio_chan_spec convst_channel[2]; void (*reset)(struct ad7476_state *); + bool has_vref; + bool has_vdrive; }; struct ad7476_state { struct spi_device *spi; const struct ad7476_chip_info *chip_info; - struct regulator *reg; + struct regulator *ref_reg; + struct gpio_desc *convst_gpio; struct spi_transfer xfer; struct spi_message msg; /* - * DMA (thus cache coherency maintenance) requires the + * DMA (thus cache coherency maintenance) may require the * transfer buffers to live in their own cache lines. * Make the buffer large enough for one 16 bit sample and one 64 bit * aligned 64 bit timestamp. */ - unsigned char data[ALIGN(2, sizeof(s64)) + sizeof(s64)] - ____cacheline_aligned; + unsigned char data[ALIGN(2, sizeof(s64)) + sizeof(s64)] __aligned(IIO_DMA_MINALIGN); }; enum ad7476_supported_device_ids { + ID_AD7091, ID_AD7091R, + ID_AD7273, + ID_AD7274, ID_AD7276, ID_AD7277, ID_AD7278, ID_AD7466, ID_AD7467, ID_AD7468, + ID_AD7475, ID_AD7495, ID_AD7940, ID_ADC081S, @@ -62,8 +72,20 @@ enum ad7476_supported_device_ids { ID_ADS7866, ID_ADS7867, ID_ADS7868, + ID_LTC2314_14, }; +static void ad7091_convst(struct ad7476_state *st) +{ + if (!st->convst_gpio) + return; + + gpiod_set_value(st->convst_gpio, 0); + udelay(1); /* CONVST pulse width: 10 ns min */ + gpiod_set_value(st->convst_gpio, 1); + udelay(1); /* Conversion time: 650 ns max */ +} + static irqreturn_t ad7476_trigger_handler(int irq, void *p) { struct iio_poll_func *pf = p; @@ -71,6 +93,8 @@ static irqreturn_t ad7476_trigger_handler(int irq, void *p) struct ad7476_state *st = iio_priv(indio_dev); int b_sent; + ad7091_convst(st); + b_sent = spi_sync(st->spi, &st->msg); if (b_sent < 0) goto done; @@ -93,6 +117,8 @@ static int ad7476_scan_direct(struct ad7476_state *st) { int ret; + ad7091_convst(st); + ret = spi_sync(st->spi, &st->msg); if (ret) return ret; @@ -124,8 +150,8 @@ static int ad7476_read_raw(struct iio_dev *indio_dev, GENMASK(st->chip_info->channel[0].scan_type.realbits - 1, 0); return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: - if (!st->chip_info->int_vref_uv) { - scale_uv = regulator_get_voltage(st->reg); + if (st->ref_reg) { + scale_uv = regulator_get_voltage(st->ref_reg); if (scale_uv < 0) return scale_uv; } else { @@ -160,15 +186,38 @@ static int ad7476_read_raw(struct iio_dev *indio_dev, #define AD7940_CHAN(bits) _AD7476_CHAN((bits), 15 - (bits), \ BIT(IIO_CHAN_INFO_RAW)) #define AD7091R_CHAN(bits) _AD7476_CHAN((bits), 16 - (bits), 0) +#define AD7091R_CONVST_CHAN(bits) _AD7476_CHAN((bits), 16 - (bits), \ + BIT(IIO_CHAN_INFO_RAW)) #define ADS786X_CHAN(bits) _AD7476_CHAN((bits), 12 - (bits), \ BIT(IIO_CHAN_INFO_RAW)) static const struct ad7476_chip_info ad7476_chip_info_tbl[] = { + [ID_AD7091] = { + .channel[0] = AD7091R_CHAN(12), + .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), + .convst_channel[0] = AD7091R_CONVST_CHAN(12), + .convst_channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), + .reset = ad7091_reset, + }, [ID_AD7091R] = { .channel[0] = AD7091R_CHAN(12), .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), + .convst_channel[0] = AD7091R_CONVST_CHAN(12), + .convst_channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), + .int_vref_uv = 2500000, + .has_vref = true, .reset = ad7091_reset, }, + [ID_AD7273] = { + .channel[0] = AD7940_CHAN(10), + .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), + .has_vref = true, + }, + [ID_AD7274] = { + .channel[0] = AD7940_CHAN(12), + .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), + .has_vref = true, + }, [ID_AD7276] = { .channel[0] = AD7940_CHAN(12), .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), @@ -193,10 +242,17 @@ static const struct ad7476_chip_info ad7476_chip_info_tbl[] = { .channel[0] = AD7476_CHAN(8), .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), }, + [ID_AD7475] = { + .channel[0] = AD7476_CHAN(12), + .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), + .has_vref = true, + .has_vdrive = true, + }, [ID_AD7495] = { .channel[0] = AD7476_CHAN(12), .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), .int_vref_uv = 2500000, + .has_vdrive = true, }, [ID_AD7940] = { .channel[0] = AD7940_CHAN(14), @@ -226,16 +282,29 @@ static const struct ad7476_chip_info ad7476_chip_info_tbl[] = { .channel[0] = ADS786X_CHAN(8), .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), }, + [ID_LTC2314_14] = { + .channel[0] = AD7940_CHAN(14), + .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), + .has_vref = true, + }, }; static const struct iio_info ad7476_info = { .read_raw = &ad7476_read_raw, }; +static void ad7476_reg_disable(void *data) +{ + struct regulator *reg = data; + + regulator_disable(reg); +} + static int ad7476_probe(struct spi_device *spi) { struct ad7476_state *st; struct iio_dev *indio_dev; + struct regulator *reg; int ret; indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); @@ -246,26 +315,89 @@ static int ad7476_probe(struct spi_device *spi) st->chip_info = &ad7476_chip_info_tbl[spi_get_device_id(spi)->driver_data]; - st->reg = devm_regulator_get(&spi->dev, "vcc"); - if (IS_ERR(st->reg)) - return PTR_ERR(st->reg); + reg = devm_regulator_get(&spi->dev, "vcc"); + if (IS_ERR(reg)) + return PTR_ERR(reg); - ret = regulator_enable(st->reg); + ret = regulator_enable(reg); if (ret) return ret; - spi_set_drvdata(spi, indio_dev); + ret = devm_add_action_or_reset(&spi->dev, ad7476_reg_disable, reg); + if (ret) + return ret; + + /* Either vcc or vref (below) as appropriate */ + if (!st->chip_info->int_vref_uv) + st->ref_reg = reg; + + if (st->chip_info->has_vref) { + + /* If a device has an internal reference vref is optional */ + if (st->chip_info->int_vref_uv) { + reg = devm_regulator_get_optional(&spi->dev, "vref"); + if (IS_ERR(reg) && (PTR_ERR(reg) != -ENODEV)) + return PTR_ERR(reg); + } else { + reg = devm_regulator_get(&spi->dev, "vref"); + if (IS_ERR(reg)) + return PTR_ERR(reg); + } + + if (!IS_ERR(reg)) { + ret = regulator_enable(reg); + if (ret) + return ret; + + ret = devm_add_action_or_reset(&spi->dev, + ad7476_reg_disable, + reg); + if (ret) + return ret; + st->ref_reg = reg; + } else { + /* + * Can only get here if device supports both internal + * and external reference, but the regulator connected + * to the external reference is not connected. + * Set the reference regulator pointer to NULL to + * indicate this. + */ + st->ref_reg = NULL; + } + } + + if (st->chip_info->has_vdrive) { + reg = devm_regulator_get(&spi->dev, "vdrive"); + if (IS_ERR(reg)) + return PTR_ERR(reg); + + ret = regulator_enable(reg); + if (ret) + return ret; + + ret = devm_add_action_or_reset(&spi->dev, ad7476_reg_disable, + reg); + if (ret) + return ret; + } + + st->convst_gpio = devm_gpiod_get_optional(&spi->dev, + "adi,conversion-start", + GPIOD_OUT_LOW); + if (IS_ERR(st->convst_gpio)) + return PTR_ERR(st->convst_gpio); st->spi = spi; - /* Establish that the iio_dev is a child of the spi device */ - indio_dev->dev.parent = &spi->dev; - indio_dev->dev.of_node = spi->dev.of_node; indio_dev->name = spi_get_device_id(spi)->name; indio_dev->modes = INDIO_DIRECT_MODE; indio_dev->channels = st->chip_info->channel; indio_dev->num_channels = 2; indio_dev->info = &ad7476_info; + + if (st->convst_gpio) + indio_dev->channels = st->chip_info->convst_channel; /* Setup default message */ st->xfer.rx_buf = &st->data; @@ -274,50 +406,29 @@ static int ad7476_probe(struct spi_device *spi) spi_message_init(&st->msg); spi_message_add_tail(&st->xfer, &st->msg); - ret = iio_triggered_buffer_setup(indio_dev, NULL, - &ad7476_trigger_handler, NULL); + ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev, NULL, + &ad7476_trigger_handler, NULL); if (ret) - goto error_disable_reg; + return ret; if (st->chip_info->reset) st->chip_info->reset(st); - ret = iio_device_register(indio_dev); - if (ret) - goto error_ring_unregister; - return 0; - -error_ring_unregister: - iio_triggered_buffer_cleanup(indio_dev); -error_disable_reg: - regulator_disable(st->reg); - - return ret; -} - -static int ad7476_remove(struct spi_device *spi) -{ - struct iio_dev *indio_dev = spi_get_drvdata(spi); - struct ad7476_state *st = iio_priv(indio_dev); - - iio_device_unregister(indio_dev); - iio_triggered_buffer_cleanup(indio_dev); - regulator_disable(st->reg); - - return 0; + return devm_iio_device_register(&spi->dev, indio_dev); } static const struct spi_device_id ad7476_id[] = { + {"ad7091", ID_AD7091}, {"ad7091r", ID_AD7091R}, - {"ad7273", ID_AD7277}, - {"ad7274", ID_AD7276}, + {"ad7273", ID_AD7273}, + {"ad7274", ID_AD7274}, {"ad7276", ID_AD7276}, {"ad7277", ID_AD7277}, {"ad7278", ID_AD7278}, {"ad7466", ID_AD7466}, {"ad7467", ID_AD7467}, {"ad7468", ID_AD7468}, - {"ad7475", ID_AD7466}, + {"ad7475", ID_AD7475}, {"ad7476", ID_AD7466}, {"ad7476a", ID_AD7466}, {"ad7477", ID_AD7467}, @@ -334,6 +445,7 @@ static const struct spi_device_id ad7476_id[] = { {"ads7866", ID_ADS7866}, {"ads7867", ID_ADS7867}, {"ads7868", ID_ADS7868}, + {"ltc2314-14", ID_LTC2314_14}, {} }; MODULE_DEVICE_TABLE(spi, ad7476_id); @@ -343,7 +455,6 @@ static struct spi_driver ad7476_driver = { .name = "ad7476", }, .probe = ad7476_probe, - .remove = ad7476_remove, .id_table = ad7476_id, }; module_spi_driver(ad7476_driver); |