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-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");
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-02 18:58:16 +0000