summaryrefslogtreecommitdiff
path: root/drivers/iio/adc
diff options
context:
space:
mode:
authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-09-17 14:42:54 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-09-17 14:42:54 -0700
commit8508317c96727a3905400796b89586c323b551ee (patch)
tree6bd8111ad71312222f0ea9ee83c3392b278e4f7c /drivers/iio/adc
parent3afcb91c418a9e50cfb79d7b6e28907d782e69d9 (diff)
parent87c5b10fd97937796dbf0769e8790a5f275b4a37 (diff)
Merge tag 'iio-for-v3.7d' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next
IIO new drivers, features and rework for the 3.7 cycle, 4th set. Here we have 1) a set cleaning up and moving the ad7476 driver out of staging. Support for a number of additional parts is also added to that driver. 2) cleanups from various people for the in kernel interface code as that is getting more an more real use and hence people are picking up on minor issues that made it through review. Also a related useful set of utility functions to avoid duplicate code for converting IIO representations to other forms. 3) a new fractional type for our read_raw / write_raw functions. This allows avoiding loss of accuracy via the in kernel interfaces in some cases as well as being rather convenient for a lot of range -> scale conversions. 4) New AD5755 DAC driver. 5) Some Blackfin timer trigger improvements including hardware pulse control for device triggering. 6) Support for the ad7091r in the ad7476 driver.
Diffstat (limited to 'drivers/iio/adc')
-rw-r--r--drivers/iio/adc/Kconfig15
-rw-r--r--drivers/iio/adc/Makefile1
-rw-r--r--drivers/iio/adc/ad7476.c332
3 files changed, 348 insertions, 0 deletions
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index d0ae71ec2aa0..03791a6de349 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -30,6 +30,21 @@ config AD7791
To compile this driver as a module, choose M here: the module will be
called ad7791.
+config AD7476
+ tristate "Analog Devices AD7476 and similar 1-channel ADCs driver"
+ depends on SPI
+ select IIO_BUFFER
+ select IIO_TRIGGERED_BUFFER
+ help
+ Say yes here to build support for Analog Devices AD7273, AD7274, AD7276,
+ AD7277, AD7278, AD7475, AD7476, AD7477, AD7478, AD7466, AD7467, AD7468,
+ AD7495, AD7910, AD7920, AD7920 SPI analog to digital converters (ADC).
+
+ If unsure, say N (but it's safe to say "Y").
+
+ To compile this driver as a module, choose M here: the
+ module will be called ad7476.
+
config AT91_ADC
tristate "Atmel AT91 ADC"
depends on ARCH_AT91
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index f187ff6c2a16..9824a70f4fd8 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -4,5 +4,6 @@
obj-$(CONFIG_AD_SIGMA_DELTA) += ad_sigma_delta.o
obj-$(CONFIG_AD7266) += ad7266.o
+obj-$(CONFIG_AD7476) += ad7476.o
obj-$(CONFIG_AD7791) += ad7791.o
obj-$(CONFIG_AT91_ADC) += at91_adc.o
diff --git a/drivers/iio/adc/ad7476.c b/drivers/iio/adc/ad7476.c
new file mode 100644
index 000000000000..7f2f45a0a48d
--- /dev/null
+++ b/drivers/iio/adc/ad7476.c
@@ -0,0 +1,332 @@
+/*
+ * AD7466/7/8 AD7476/5/7/8 (A) SPI ADC driver
+ *
+ * Copyright 2010 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/spi/spi.h>
+#include <linux/regulator/consumer.h>
+#include <linux/err.h>
+#include <linux/module.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#define RES_MASK(bits) ((1 << (bits)) - 1)
+
+struct ad7476_state;
+
+struct ad7476_chip_info {
+ unsigned int int_vref_uv;
+ struct iio_chan_spec channel[2];
+ void (*reset)(struct ad7476_state *);
+};
+
+struct ad7476_state {
+ struct spi_device *spi;
+ const struct ad7476_chip_info *chip_info;
+ struct regulator *reg;
+ struct spi_transfer xfer;
+ struct spi_message msg;
+ /*
+ * DMA (thus cache coherency maintenance) requires 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;
+};
+
+enum ad7476_supported_device_ids {
+ ID_AD7091R,
+ ID_AD7276,
+ ID_AD7277,
+ ID_AD7278,
+ ID_AD7466,
+ ID_AD7467,
+ ID_AD7468,
+ ID_AD7495,
+ ID_AD7940,
+};
+
+static irqreturn_t ad7476_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct ad7476_state *st = iio_priv(indio_dev);
+ s64 time_ns;
+ int b_sent;
+
+ b_sent = spi_sync(st->spi, &st->msg);
+ if (b_sent < 0)
+ goto done;
+
+ time_ns = iio_get_time_ns();
+
+ if (indio_dev->scan_timestamp)
+ ((s64 *)st->data)[1] = time_ns;
+
+ iio_push_to_buffer(indio_dev->buffer, st->data);
+done:
+ iio_trigger_notify_done(indio_dev->trig);
+
+ return IRQ_HANDLED;
+}
+
+static void ad7091_reset(struct ad7476_state *st)
+{
+ /* Any transfers with 8 scl cycles will reset the device */
+ spi_read(st->spi, st->data, 1);
+}
+
+static int ad7476_scan_direct(struct ad7476_state *st)
+{
+ int ret;
+
+ ret = spi_sync(st->spi, &st->msg);
+ if (ret)
+ return ret;
+
+ return be16_to_cpup((__be16 *)st->data);
+}
+
+static int ad7476_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long m)
+{
+ int ret;
+ struct ad7476_state *st = iio_priv(indio_dev);
+ int scale_uv;
+
+ switch (m) {
+ case IIO_CHAN_INFO_RAW:
+ mutex_lock(&indio_dev->mlock);
+ if (iio_buffer_enabled(indio_dev))
+ ret = -EBUSY;
+ else
+ ret = ad7476_scan_direct(st);
+ mutex_unlock(&indio_dev->mlock);
+
+ if (ret < 0)
+ return ret;
+ *val = (ret >> st->chip_info->channel[0].scan_type.shift) &
+ RES_MASK(st->chip_info->channel[0].scan_type.realbits);
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ if (!st->chip_info->int_vref_uv) {
+ scale_uv = regulator_get_voltage(st->reg);
+ if (scale_uv < 0)
+ return scale_uv;
+ } else {
+ scale_uv = st->chip_info->int_vref_uv;
+ }
+ scale_uv >>= chan->scan_type.realbits;
+ *val = scale_uv / 1000;
+ *val2 = (scale_uv % 1000) * 1000;
+ return IIO_VAL_INT_PLUS_MICRO;
+ }
+ return -EINVAL;
+}
+
+#define _AD7476_CHAN(bits, _shift, _info_mask) \
+ { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .info_mask = _info_mask | \
+ IIO_CHAN_INFO_SCALE_SHARED_BIT, \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = (bits), \
+ .storagebits = 16, \
+ .shift = (_shift), \
+ .endianness = IIO_BE, \
+ }, \
+}
+
+#define AD7476_CHAN(bits) _AD7476_CHAN((bits), 13 - (bits), \
+ IIO_CHAN_INFO_RAW_SEPARATE_BIT)
+#define AD7940_CHAN(bits) _AD7476_CHAN((bits), 15 - (bits), \
+ IIO_CHAN_INFO_RAW_SEPARATE_BIT)
+#define AD7091R_CHAN(bits) _AD7476_CHAN((bits), 16 - (bits), 0)
+
+static const struct ad7476_chip_info ad7476_chip_info_tbl[] = {
+ [ID_AD7091R] = {
+ .channel[0] = AD7091R_CHAN(12),
+ .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+ .reset = ad7091_reset,
+ },
+ [ID_AD7276] = {
+ .channel[0] = AD7940_CHAN(12),
+ .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+ },
+ [ID_AD7277] = {
+ .channel[0] = AD7940_CHAN(10),
+ .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+ },
+ [ID_AD7278] = {
+ .channel[0] = AD7940_CHAN(8),
+ .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+ },
+ [ID_AD7466] = {
+ .channel[0] = AD7476_CHAN(12),
+ .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+ },
+ [ID_AD7467] = {
+ .channel[0] = AD7476_CHAN(10),
+ .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+ },
+ [ID_AD7468] = {
+ .channel[0] = AD7476_CHAN(8),
+ .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+ },
+ [ID_AD7495] = {
+ .channel[0] = AD7476_CHAN(12),
+ .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+ .int_vref_uv = 2500000,
+ },
+ [ID_AD7940] = {
+ .channel[0] = AD7940_CHAN(14),
+ .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+ },
+};
+
+static const struct iio_info ad7476_info = {
+ .driver_module = THIS_MODULE,
+ .read_raw = &ad7476_read_raw,
+};
+
+static int __devinit ad7476_probe(struct spi_device *spi)
+{
+ struct ad7476_state *st;
+ struct iio_dev *indio_dev;
+ int ret;
+
+ indio_dev = iio_device_alloc(sizeof(*st));
+ if (indio_dev == NULL) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+ st = iio_priv(indio_dev);
+ st->chip_info =
+ &ad7476_chip_info_tbl[spi_get_device_id(spi)->driver_data];
+
+ st->reg = regulator_get(&spi->dev, "vcc");
+ if (IS_ERR(st->reg)) {
+ ret = PTR_ERR(st->reg);
+ goto error_free_dev;
+ }
+
+ ret = regulator_enable(st->reg);
+ if (ret)
+ goto error_put_reg;
+
+ spi_set_drvdata(spi, indio_dev);
+
+ st->spi = spi;
+
+ /* Establish that the iio_dev is a child of the spi device */
+ indio_dev->dev.parent = &spi->dev;
+ 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;
+ /* Setup default message */
+
+ st->xfer.rx_buf = &st->data;
+ st->xfer.len = st->chip_info->channel[0].scan_type.storagebits / 8;
+
+ 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);
+ if (ret)
+ goto error_disable_reg;
+
+ 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);
+error_put_reg:
+ regulator_put(st->reg);
+error_free_dev:
+ iio_device_free(indio_dev);
+
+error_ret:
+ return ret;
+}
+
+static int __devexit 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);
+ regulator_put(st->reg);
+ iio_device_free(indio_dev);
+
+ return 0;
+}
+
+static const struct spi_device_id ad7476_id[] = {
+ {"ad7091r", ID_AD7091R},
+ {"ad7273", ID_AD7277},
+ {"ad7274", ID_AD7276},
+ {"ad7276", ID_AD7276},
+ {"ad7277", ID_AD7277},
+ {"ad7278", ID_AD7278},
+ {"ad7466", ID_AD7466},
+ {"ad7467", ID_AD7467},
+ {"ad7468", ID_AD7468},
+ {"ad7475", ID_AD7466},
+ {"ad7476", ID_AD7466},
+ {"ad7476a", ID_AD7466},
+ {"ad7477", ID_AD7467},
+ {"ad7477a", ID_AD7467},
+ {"ad7478", ID_AD7468},
+ {"ad7478a", ID_AD7468},
+ {"ad7495", ID_AD7495},
+ {"ad7910", ID_AD7467},
+ {"ad7920", ID_AD7466},
+ {"ad7940", ID_AD7940},
+ {}
+};
+MODULE_DEVICE_TABLE(spi, ad7476_id);
+
+static struct spi_driver ad7476_driver = {
+ .driver = {
+ .name = "ad7476",
+ .owner = THIS_MODULE,
+ },
+ .probe = ad7476_probe,
+ .remove = __devexit_p(ad7476_remove),
+ .id_table = ad7476_id,
+};
+module_spi_driver(ad7476_driver);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("Analog Devices AD7476 and similar 1-channel ADCs");
+MODULE_LICENSE("GPL v2");