Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
---
drivers/staging/iio/adc/Kconfig | 1 +
drivers/staging/iio/adc/ad7780.c | 186 ++++++++++++++------------------------
2 files changed, 71 insertions(+), 116 deletions(-)
diff --git a/drivers/staging/iio/adc/Kconfig b/drivers/staging/iio/adc/Kconfig
index 67711b7..fc7b7f6 100644
--- a/drivers/staging/iio/adc/Kconfig
+++ b/drivers/staging/iio/adc/Kconfig
@@ -99,6 +99,7 @@ config AD7780
tristate "Analog Devices AD7780 AD7781 ADC driver"
depends on SPI
depends on GPIOLIB
+ select AD_SIGMA_DELTA
help
Say yes here to build support for Analog Devices
AD7780 and AD7781 SPI analog to digital converters (ADC).
diff --git a/drivers/staging/iio/adc/ad7780.c b/drivers/staging/iio/adc/ad7780.c
index 19ee49c..853f8b1 100644
--- a/drivers/staging/iio/adc/ad7780.c
+++ b/drivers/staging/iio/adc/ad7780.c
@@ -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"
@@ -37,20 +38,13 @@ struct ad7780_chip_info {
};
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 {
@@ -58,28 +52,30 @@ enum ad7780_supported_device_ids {
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);
+ gpio_set_value(st->powerdown_gpio, val);
- return ret;
+ return 0;
}
static int ad7780_read_raw(struct iio_dev *indio_dev,
@@ -89,89 +85,57 @@ 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);
+
+ if ((raw_sample & AD7780_ERR) ||
+ !((raw_sample & AD7780_PAT0) && !(raw_sample & AD7780_PAT1)))
+ 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,
+};
+
static const struct ad7780_chip_info ad7780_chip_info_tbl[] = {
[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 = AD_SD_CHANNEL(1, 0, 0, 24, 32, 8),
},
[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 = AD_SD_CHANNEL(1, 0, 0, 20, 32, 12),
},
};
-/**
- * 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,
@@ -194,6 +158,9 @@ static int __devinit ad7780_probe(struct spi_device *spi)
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)) {
@@ -207,7 +174,7 @@ 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;
+ st->powerdown_gpio = pdata->gpio_pdrst;
if (pdata && pdata->vref_mv)
st->int_vref_mv = pdata->vref_mv;
@@ -217,7 +184,6 @@ 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 +192,27 @@ 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 */
-
- 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;
}
- 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);
+ gpio_free(pdata->gpio_pdrst);
error_disable_reg:
if (!IS_ERR(st->reg))
regulator_disable(st->reg);
@@ -278,8 +231,9 @@ static int ad7780_remove(struct spi_device *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);
+
+ gpio_free(st->powerdown_gpio);
if (!IS_ERR(st->reg)) {
regulator_disable(st->reg);
regulator_put(st->reg);