diff options
Diffstat (limited to 'drivers/staging/iio/adc/ad7780.c')
-rw-r--r-- | drivers/staging/iio/adc/ad7780.c | 237 |
1 files changed, 109 insertions, 128 deletions
diff --git a/drivers/staging/iio/adc/ad7780.c b/drivers/staging/iio/adc/ad7780.c index 19ee49c95de4..0a1328b8657f 100644 --- a/drivers/staging/iio/adc/ad7780.c +++ b/drivers/staging/iio/adc/ad7780.c @@ -1,5 +1,5 @@ /* - * AD7780/AD7781 SPI ADC driver + * AD7170/AD7171 and AD7780/AD7781 SPI ADC driver * * Copyright 2011 Analog Devices Inc. * @@ -20,6 +20,7 @@ #include <linux/iio/iio.h> #include <linux/iio/sysfs.h> +#include <linux/iio/adc/ad_sigma_delta.h> #include "ad7780.h" @@ -33,53 +34,53 @@ #define AD7780_PAT0 (1 << 0) struct ad7780_chip_info { - struct iio_chan_spec channel; + struct iio_chan_spec channel; + unsigned int pattern_mask; + unsigned int pattern; }; struct ad7780_state { - struct spi_device *spi; const struct ad7780_chip_info *chip_info; struct regulator *reg; - struct ad7780_platform_data *pdata; - wait_queue_head_t wq_data_avail; - bool done; + int powerdown_gpio; + unsigned int gain; u16 int_vref_mv; - struct spi_transfer xfer; - struct spi_message msg; - /* - * DMA (thus cache coherency maintenance) requires the - * transfer buffers to live in their own cache lines. - */ - unsigned int data ____cacheline_aligned; + + struct ad_sigma_delta sd; }; enum ad7780_supported_device_ids { + ID_AD7170, + ID_AD7171, ID_AD7780, ID_AD7781, }; -static int ad7780_read(struct ad7780_state *st, int *val) +static struct ad7780_state *ad_sigma_delta_to_ad7780(struct ad_sigma_delta *sd) { - int ret; - - spi_bus_lock(st->spi->master); - - enable_irq(st->spi->irq); - st->done = false; - gpio_set_value(st->pdata->gpio_pdrst, 1); + return container_of(sd, struct ad7780_state, sd); +} - ret = wait_event_interruptible(st->wq_data_avail, st->done); - disable_irq_nosync(st->spi->irq); - if (ret) - goto out; +static int ad7780_set_mode(struct ad_sigma_delta *sigma_delta, + enum ad_sigma_delta_mode mode) +{ + struct ad7780_state *st = ad_sigma_delta_to_ad7780(sigma_delta); + unsigned val; + + switch (mode) { + case AD_SD_MODE_SINGLE: + case AD_SD_MODE_CONTINUOUS: + val = 1; + break; + default: + val = 0; + break; + } - ret = spi_sync_locked(st->spi, &st->msg); - *val = be32_to_cpu(st->data); -out: - gpio_set_value(st->pdata->gpio_pdrst, 0); - spi_bus_unlock(st->spi->master); + if (gpio_is_valid(st->powerdown_gpio)) + gpio_set_value(st->powerdown_gpio, val); - return ret; + return 0; } static int ad7780_read_raw(struct iio_dev *indio_dev, @@ -89,89 +90,75 @@ static int ad7780_read_raw(struct iio_dev *indio_dev, long m) { struct ad7780_state *st = iio_priv(indio_dev); - struct iio_chan_spec channel = st->chip_info->channel; - int ret, smpl = 0; unsigned long scale_uv; switch (m) { case IIO_CHAN_INFO_RAW: - mutex_lock(&indio_dev->mlock); - ret = ad7780_read(st, &smpl); - mutex_unlock(&indio_dev->mlock); - - if (ret < 0) - return ret; - - if ((smpl & AD7780_ERR) || - !((smpl & AD7780_PAT0) && !(smpl & AD7780_PAT1))) - return -EIO; - - *val = (smpl >> channel.scan_type.shift) & - ((1 << (channel.scan_type.realbits)) - 1); - *val -= (1 << (channel.scan_type.realbits - 1)); - - if (!(smpl & AD7780_GAIN)) - *val *= 128; - - return IIO_VAL_INT; + return ad_sigma_delta_single_conversion(indio_dev, chan, val); case IIO_CHAN_INFO_SCALE: - scale_uv = (st->int_vref_mv * 100000) - >> (channel.scan_type.realbits - 1); + scale_uv = (st->int_vref_mv * 100000 * st->gain) + >> (chan->scan_type.realbits - 1); *val = scale_uv / 100000; *val2 = (scale_uv % 100000) * 10; return IIO_VAL_INT_PLUS_MICRO; + case IIO_CHAN_INFO_OFFSET: + *val -= (1 << (chan->scan_type.realbits - 1)); + return IIO_VAL_INT; } + return -EINVAL; } +static int ad7780_postprocess_sample(struct ad_sigma_delta *sigma_delta, + unsigned int raw_sample) +{ + struct ad7780_state *st = ad_sigma_delta_to_ad7780(sigma_delta); + const struct ad7780_chip_info *chip_info = st->chip_info; + + if ((raw_sample & AD7780_ERR) || + ((raw_sample & chip_info->pattern_mask) != chip_info->pattern)) + return -EIO; + + if (raw_sample & AD7780_GAIN) + st->gain = 1; + else + st->gain = 128; + + return 0; +} + +static const struct ad_sigma_delta_info ad7780_sigma_delta_info = { + .set_mode = ad7780_set_mode, + .postprocess_sample = ad7780_postprocess_sample, + .has_registers = false, +}; + +#define AD7780_CHANNEL(bits, wordsize) \ + AD_SD_CHANNEL(1, 0, 0, bits, 32, wordsize - bits) + static const struct ad7780_chip_info ad7780_chip_info_tbl[] = { + [ID_AD7170] = { + .channel = AD7780_CHANNEL(12, 24), + .pattern = 0x5, + .pattern_mask = 0x7, + }, + [ID_AD7171] = { + .channel = AD7780_CHANNEL(16, 24), + .pattern = 0x5, + .pattern_mask = 0x7, + }, [ID_AD7780] = { - .channel = { - .type = IIO_VOLTAGE, - .indexed = 1, - .channel = 0, - .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | - IIO_CHAN_INFO_SCALE_SHARED_BIT | - IIO_CHAN_INFO_OFFSET_SHARED_BIT, - .scan_type = { - .sign = 'u', - .realbits = 24, - .storagebits = 32, - .shift = 8, - }, - }, + .channel = AD7780_CHANNEL(24, 32), + .pattern = 0x1, + .pattern_mask = 0x3, }, [ID_AD7781] = { - .channel = { - .type = IIO_VOLTAGE, - .indexed = 1, - .channel = 0, - .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | - IIO_CHAN_INFO_SCALE_SHARED_BIT | - IIO_CHAN_INFO_OFFSET_SHARED_BIT, - .scan_type = { - .sign = 'u', - .realbits = 20, - .storagebits = 32, - .shift = 12, - }, - }, + .channel = AD7780_CHANNEL(20, 32), + .pattern = 0x1, + .pattern_mask = 0x3, }, }; -/** - * Interrupt handler - */ -static irqreturn_t ad7780_interrupt(int irq, void *dev_id) -{ - struct ad7780_state *st = dev_id; - - st->done = true; - wake_up_interruptible(&st->wq_data_avail); - - return IRQ_HANDLED; -}; - static const struct iio_info ad7780_info = { .read_raw = &ad7780_read_raw, .driver_module = THIS_MODULE, @@ -184,16 +171,14 @@ static int __devinit ad7780_probe(struct spi_device *spi) struct iio_dev *indio_dev; int ret, voltage_uv = 0; - if (!pdata) { - dev_dbg(&spi->dev, "no platform data?\n"); - return -ENODEV; - } - indio_dev = iio_device_alloc(sizeof(*st)); if (indio_dev == NULL) return -ENOMEM; st = iio_priv(indio_dev); + st->gain = 1; + + ad_sd_init(&st->sd, indio_dev, spi, &ad7780_sigma_delta_info); st->reg = regulator_get(&spi->dev, "vcc"); if (!IS_ERR(st->reg)) { @@ -207,8 +192,6 @@ static int __devinit ad7780_probe(struct spi_device *spi) st->chip_info = &ad7780_chip_info_tbl[spi_get_device_id(spi)->driver_data]; - st->pdata = pdata; - if (pdata && pdata->vref_mv) st->int_vref_mv = pdata->vref_mv; else if (voltage_uv) @@ -217,7 +200,6 @@ static int __devinit ad7780_probe(struct spi_device *spi) dev_warn(&spi->dev, "reference voltage unspecified\n"); spi_set_drvdata(spi, indio_dev); - st->spi = spi; indio_dev->dev.parent = &spi->dev; indio_dev->name = spi_get_device_id(spi)->name; @@ -226,40 +208,34 @@ static int __devinit ad7780_probe(struct spi_device *spi) indio_dev->num_channels = 1; indio_dev->info = &ad7780_info; - init_waitqueue_head(&st->wq_data_avail); - - /* Setup default message */ + if (pdata && gpio_is_valid(pdata->gpio_pdrst)) { - st->xfer.rx_buf = &st->data; - st->xfer.len = st->chip_info->channel.scan_type.storagebits / 8; - - spi_message_init(&st->msg); - spi_message_add_tail(&st->xfer, &st->msg); - - ret = gpio_request_one(st->pdata->gpio_pdrst, GPIOF_OUT_INIT_LOW, + ret = gpio_request_one(pdata->gpio_pdrst, GPIOF_OUT_INIT_LOW, "AD7780 /PDRST"); - if (ret) { - dev_err(&spi->dev, "failed to request GPIO PDRST\n"); - goto error_disable_reg; + if (ret) { + dev_err(&spi->dev, "failed to request GPIO PDRST\n"); + goto error_disable_reg; + } + st->powerdown_gpio = pdata->gpio_pdrst; + } else { + st->powerdown_gpio = -1; } - ret = request_irq(spi->irq, ad7780_interrupt, - IRQF_TRIGGER_FALLING, spi_get_device_id(spi)->name, st); + ret = ad_sd_setup_buffer_and_trigger(indio_dev); if (ret) goto error_free_gpio; - disable_irq(spi->irq); - ret = iio_device_register(indio_dev); if (ret) - goto error_free_irq; + goto error_cleanup_buffer_and_trigger; return 0; -error_free_irq: - free_irq(spi->irq, st); +error_cleanup_buffer_and_trigger: + ad_sd_cleanup_buffer_and_trigger(indio_dev); error_free_gpio: - gpio_free(st->pdata->gpio_pdrst); + if (pdata && gpio_is_valid(pdata->gpio_pdrst)) + gpio_free(pdata->gpio_pdrst); error_disable_reg: if (!IS_ERR(st->reg)) regulator_disable(st->reg); @@ -272,14 +248,17 @@ error_put_reg: return ret; } -static int ad7780_remove(struct spi_device *spi) +static int __devexit ad7780_remove(struct spi_device *spi) { struct iio_dev *indio_dev = spi_get_drvdata(spi); struct ad7780_state *st = iio_priv(indio_dev); iio_device_unregister(indio_dev); - free_irq(spi->irq, st); - gpio_free(st->pdata->gpio_pdrst); + ad_sd_cleanup_buffer_and_trigger(indio_dev); + + if (gpio_is_valid(st->powerdown_gpio)) + gpio_free(st->powerdown_gpio); + if (!IS_ERR(st->reg)) { regulator_disable(st->reg); regulator_put(st->reg); @@ -290,6 +269,8 @@ static int ad7780_remove(struct spi_device *spi) } static const struct spi_device_id ad7780_id[] = { + {"ad7170", ID_AD7170}, + {"ad7171", ID_AD7171}, {"ad7780", ID_AD7780}, {"ad7781", ID_AD7781}, {} @@ -308,5 +289,5 @@ static struct spi_driver ad7780_driver = { module_spi_driver(ad7780_driver); MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); -MODULE_DESCRIPTION("Analog Devices AD7780/1 ADC"); +MODULE_DESCRIPTION("Analog Devices AD7780 and similar ADCs"); MODULE_LICENSE("GPL v2"); |