staging:iio:dac: Add AD5360 driver
authorLars-Peter Clausen <lars@metafoo.de>
Thu, 20 Oct 2011 08:46:38 +0000 (10:46 +0200)
committerGreg Kroah-Hartman <gregkh@suse.de>
Sun, 23 Oct 2011 08:15:02 +0000 (10:15 +0200)
This patch adds support for the Analog Devices AD5360, AD5361, AD5362, AD5363,
AD5370, AD5371, AD5372, AD5373 multi-channel digital-to-analog converters.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/staging/iio/dac/Kconfig
drivers/staging/iio/dac/Makefile
drivers/staging/iio/dac/ad5360.c [new file with mode: 0644]

index 72281f87caa445b5dae5fc13d218f0eff11e0449..fac8549dc8e77e87b8473e4b308b6c2185c83a02 100644 (file)
@@ -13,6 +13,17 @@ config AD5064
          To compile this driver as a module, choose M here: the
          module will be called ad5064.
 
+config AD5360
+       tristate "Analog Devices Analog Devices AD5360/61/62/63/70/71/73 DAC driver"
+       depends on SPI
+       help
+         Say yes here to build support for Analog Devices AD5360, AD5361,
+         AD5362, AD5363, AD5370, AD5371, AD5373 multi-channel
+         Digital to Analog Converters (DAC).
+
+         To compile this driver as module choose M here: the module will be called
+         ad5360.
+
 config AD5624R_SPI
        tristate "Analog Devices AD5624/44/64R DAC spi driver"
        depends on SPI
index ea4975031fed98f435e3fa41c5c2f248eafa631d..07b6f5ebdb52fba6572ab67d0b83352945cc77fe 100644 (file)
@@ -2,6 +2,7 @@
 # Makefile for industrial I/O DAC drivers
 #
 
+obj-$(CONFIG_AD5360) += ad5360.o
 obj-$(CONFIG_AD5624R_SPI) += ad5624r_spi.o
 obj-$(CONFIG_AD5064) += ad5064.o
 obj-$(CONFIG_AD5504) += ad5504.o
diff --git a/drivers/staging/iio/dac/ad5360.c b/drivers/staging/iio/dac/ad5360.c
new file mode 100644 (file)
index 0000000..72d0f3f
--- /dev/null
@@ -0,0 +1,581 @@
+/*
+ * Analog devices AD5360, AD5361, AD5362, AD5363, AD5370, AD5371, AD5373
+ * multi-channel Digital to Analog Converters driver
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/spi/spi.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/regulator/consumer.h>
+
+#include "../iio.h"
+#include "../sysfs.h"
+#include "dac.h"
+
+#define AD5360_CMD(x)                          ((x) << 22)
+#define AD5360_ADDR(x)                         ((x) << 16)
+
+#define AD5360_READBACK_TYPE(x)                        ((x) << 13)
+#define AD5360_READBACK_ADDR(x)                        ((x) << 7)
+
+#define AD5360_CHAN_ADDR(chan)                 ((chan) + 0x8)
+
+#define AD5360_CMD_WRITE_DATA                  0x3
+#define AD5360_CMD_WRITE_OFFSET                        0x2
+#define AD5360_CMD_WRITE_GAIN                  0x1
+#define AD5360_CMD_SPECIAL_FUNCTION            0x0
+
+/* Special function register addresses */
+#define AD5360_REG_SF_NOP                      0x0
+#define AD5360_REG_SF_CTRL                     0x1
+#define AD5360_REG_SF_OFS(x)                   (0x2 + (x))
+#define AD5360_REG_SF_READBACK                 0x5
+
+#define AD5360_SF_CTRL_PWR_DOWN                        BIT(0)
+
+#define AD5360_READBACK_X1A                    0x0
+#define AD5360_READBACK_X1B                    0x1
+#define AD5360_READBACK_OFFSET                 0x2
+#define AD5360_READBACK_GAIN                   0x3
+#define AD5360_READBACK_SF                     0x4
+
+
+/**
+ * struct ad5360_chip_info - chip specific information
+ * @channel_template:  channel specification template
+ * @num_channels:      number of channels
+ * @channels_per_group:        number of channels per group
+ * @num_vrefs:         number of vref supplies for the chip
+*/
+
+struct ad5360_chip_info {
+       struct iio_chan_spec    channel_template;
+       unsigned int            num_channels;
+       unsigned int            channels_per_group;
+       unsigned int            num_vrefs;
+};
+
+/**
+ * struct ad5360_state - driver instance specific data
+ * @spi:               spi_device
+ * @chip_info:         chip model specific constants, available modes etc
+ * @vref_reg:          vref supply regulators
+ * @ctrl:              control register cache
+ * @data:              spi transfer buffers
+ */
+
+struct ad5360_state {
+       struct spi_device               *spi;
+       const struct ad5360_chip_info   *chip_info;
+       struct regulator_bulk_data      vref_reg[3];
+       unsigned int                    ctrl;
+
+       /*
+        * DMA (thus cache coherency maintenance) requires the
+        * transfer buffers to live in their own cache lines.
+        */
+       union {
+               __be32 d32;
+               u8 d8[4];
+       } data[2] ____cacheline_aligned;
+};
+
+enum ad5360_type {
+       ID_AD5360,
+       ID_AD5361,
+       ID_AD5362,
+       ID_AD5363,
+       ID_AD5370,
+       ID_AD5371,
+       ID_AD5372,
+       ID_AD5373,
+};
+
+#define AD5360_CHANNEL(bits) {                                 \
+       .type = IIO_VOLTAGE,                                    \
+       .indexed = 1,                                           \
+       .output = 1,                                            \
+       .info_mask = (1 << IIO_CHAN_INFO_SCALE_SEPARATE) |      \
+               (1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |          \
+               (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |      \
+               (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE),        \
+       .scan_type = IIO_ST('u', (bits), 16, 16 - (bits))       \
+}
+
+static const struct ad5360_chip_info ad5360_chip_info_tbl[] = {
+       [ID_AD5360] = {
+               .channel_template = AD5360_CHANNEL(16),
+               .num_channels = 16,
+               .channels_per_group = 8,
+               .num_vrefs = 2,
+       },
+       [ID_AD5361] = {
+               .channel_template = AD5360_CHANNEL(14),
+               .num_channels = 16,
+               .channels_per_group = 8,
+               .num_vrefs = 2,
+       },
+       [ID_AD5362] = {
+               .channel_template = AD5360_CHANNEL(16),
+               .num_channels = 8,
+               .channels_per_group = 4,
+               .num_vrefs = 2,
+       },
+       [ID_AD5363] = {
+               .channel_template = AD5360_CHANNEL(14),
+               .num_channels = 8,
+               .channels_per_group = 4,
+               .num_vrefs = 2,
+       },
+       [ID_AD5370] = {
+               .channel_template = AD5360_CHANNEL(16),
+               .num_channels = 40,
+               .channels_per_group = 8,
+               .num_vrefs = 2,
+       },
+       [ID_AD5371] = {
+               .channel_template = AD5360_CHANNEL(14),
+               .num_channels = 40,
+               .channels_per_group = 8,
+               .num_vrefs = 3,
+       },
+       [ID_AD5372] = {
+               .channel_template = AD5360_CHANNEL(16),
+               .num_channels = 32,
+               .channels_per_group = 8,
+               .num_vrefs = 2,
+       },
+       [ID_AD5373] = {
+               .channel_template = AD5360_CHANNEL(14),
+               .num_channels = 32,
+               .channels_per_group = 8,
+               .num_vrefs = 2,
+       },
+};
+
+static unsigned int ad5360_get_channel_vref_index(struct ad5360_state *st,
+       unsigned int channel)
+{
+       unsigned int i;
+
+       /* The first groups have their own vref, while the remaining groups
+        * share the last vref */
+       i = channel / st->chip_info->channels_per_group;
+       if (i >= st->chip_info->num_vrefs)
+               i = st->chip_info->num_vrefs - 1;
+
+       return i;
+}
+
+static int ad5360_get_channel_vref(struct ad5360_state *st,
+       unsigned int channel)
+{
+       unsigned int i = ad5360_get_channel_vref_index(st, channel);
+
+       return regulator_get_voltage(st->vref_reg[i].consumer);
+}
+
+
+static int ad5360_write_unlocked(struct iio_dev *indio_dev,
+       unsigned int cmd, unsigned int addr, unsigned int val,
+       unsigned int shift)
+{
+       struct ad5360_state *st = iio_priv(indio_dev);
+
+       val <<= shift;
+       val |= AD5360_CMD(cmd) | AD5360_ADDR(addr);
+       st->data[0].d32 = cpu_to_be32(val);
+
+       return spi_write(st->spi, &st->data[0].d8[1], 3);
+}
+
+static int ad5360_write(struct iio_dev *indio_dev, unsigned int cmd,
+       unsigned int addr, unsigned int val, unsigned int shift)
+{
+       int ret;
+
+       mutex_lock(&indio_dev->mlock);
+       ret = ad5360_write_unlocked(indio_dev, cmd, addr, val, shift);
+       mutex_unlock(&indio_dev->mlock);
+
+       return ret;
+}
+
+static int ad5360_read(struct iio_dev *indio_dev, unsigned int type,
+       unsigned int addr)
+{
+       struct ad5360_state *st = iio_priv(indio_dev);
+       struct spi_message m;
+       int ret;
+       struct spi_transfer t[] = {
+               {
+                       .tx_buf = &st->data[0].d8[1],
+                       .len = 3,
+                       .cs_change = 1,
+               }, {
+                       .rx_buf = &st->data[1].d8[1],
+                       .len = 3,
+               },
+       };
+
+       spi_message_init(&m);
+       spi_message_add_tail(&t[0], &m);
+       spi_message_add_tail(&t[1], &m);
+
+       mutex_lock(&indio_dev->mlock);
+
+       st->data[0].d32 = cpu_to_be32(AD5360_CMD(AD5360_CMD_SPECIAL_FUNCTION) |
+               AD5360_ADDR(AD5360_REG_SF_READBACK) |
+               AD5360_READBACK_TYPE(type) |
+               AD5360_READBACK_ADDR(addr));
+
+       ret = spi_sync(st->spi, &m);
+       if (ret >= 0)
+               ret = be32_to_cpu(st->data[1].d32) & 0xffff;
+
+       mutex_unlock(&indio_dev->mlock);
+
+       return ret;
+}
+
+static ssize_t ad5360_read_dac_powerdown(struct device *dev,
+                                          struct device_attribute *attr,
+                                          char *buf)
+{
+       struct iio_dev *indio_dev = dev_get_drvdata(dev);
+       struct ad5360_state *st = iio_priv(indio_dev);
+
+       return sprintf(buf, "%d\n", (bool)(st->ctrl & AD5360_SF_CTRL_PWR_DOWN));
+}
+
+static int ad5360_update_ctrl(struct iio_dev *indio_dev, unsigned int set,
+       unsigned int clr)
+{
+       struct ad5360_state *st = iio_priv(indio_dev);
+       unsigned int ret;
+
+       mutex_lock(&indio_dev->mlock);
+
+       st->ctrl |= set;
+       st->ctrl &= ~clr;
+
+       ret = ad5360_write_unlocked(indio_dev, AD5360_CMD_SPECIAL_FUNCTION,
+                       AD5360_REG_SF_CTRL, st->ctrl, 0);
+
+       mutex_unlock(&indio_dev->mlock);
+
+       return ret;
+}
+
+static ssize_t ad5360_write_dac_powerdown(struct device *dev,
+       struct device_attribute *attr, const char *buf, size_t len)
+{
+       struct iio_dev *indio_dev = dev_get_drvdata(dev);
+       bool pwr_down;
+       int ret;
+
+       ret = strtobool(buf, &pwr_down);
+       if (ret)
+               return ret;
+
+       if (pwr_down)
+               ret = ad5360_update_ctrl(indio_dev, AD5360_SF_CTRL_PWR_DOWN, 0);
+       else
+               ret = ad5360_update_ctrl(indio_dev, 0, AD5360_SF_CTRL_PWR_DOWN);
+
+       return ret ? ret : len;
+}
+
+static IIO_DEVICE_ATTR(out_voltage_powerdown,
+                       S_IRUGO | S_IWUSR,
+                       ad5360_read_dac_powerdown,
+                       ad5360_write_dac_powerdown, 0);
+
+static struct attribute *ad5360_attributes[] = {
+       &iio_dev_attr_out_voltage_powerdown.dev_attr.attr,
+       NULL,
+};
+
+static const struct attribute_group ad5360_attribute_group = {
+       .attrs = ad5360_attributes,
+};
+
+static int ad5360_write_raw(struct iio_dev *indio_dev,
+                              struct iio_chan_spec const *chan,
+                              int val,
+                              int val2,
+                              long mask)
+{
+       struct ad5360_state *st = iio_priv(indio_dev);
+       int max_val = (1 << chan->scan_type.realbits);
+       unsigned int ofs_index;
+
+       switch (mask) {
+       case 0:
+               if (val >= max_val || val < 0)
+                       return -EINVAL;
+
+               return ad5360_write(indio_dev, AD5360_CMD_WRITE_DATA,
+                                chan->address, val, chan->scan_type.shift);
+
+       case (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE):
+               if (val >= max_val || val < 0)
+                       return -EINVAL;
+
+               return ad5360_write(indio_dev, AD5360_CMD_WRITE_OFFSET,
+                                chan->address, val, chan->scan_type.shift);
+
+       case (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE):
+               if (val >= max_val || val < 0)
+                       return -EINVAL;
+
+               return ad5360_write(indio_dev, AD5360_CMD_WRITE_GAIN,
+                                chan->address, val, chan->scan_type.shift);
+
+       case (1 << IIO_CHAN_INFO_OFFSET_SEPARATE):
+               if (val <= -max_val || val > 0)
+                       return -EINVAL;
+
+               val = -val;
+
+               /* offset is supposed to have the same scale as raw, but it
+                * is always 14bits wide, so on a chip where the raw value has
+                * more bits, we need to shift offset. */
+               val >>= (chan->scan_type.realbits - 14);
+
+               /* There is one DAC offset register per vref. Changing one
+                * channels offset will also change the offset for all other
+                * channels which share the same vref supply. */
+               ofs_index = ad5360_get_channel_vref_index(st, chan->channel);
+               return ad5360_write(indio_dev, AD5360_CMD_SPECIAL_FUNCTION,
+                                AD5360_REG_SF_OFS(ofs_index), val, 0);
+       default:
+               break;
+       }
+
+       return -EINVAL;
+}
+
+static int ad5360_read_raw(struct iio_dev *indio_dev,
+                          struct iio_chan_spec const *chan,
+                          int *val,
+                          int *val2,
+                          long m)
+{
+       struct ad5360_state *st = iio_priv(indio_dev);
+       unsigned long scale_uv;
+       unsigned int ofs_index;
+       int ret;
+
+       switch (m) {
+       case 0:
+               ret = ad5360_read(indio_dev, AD5360_READBACK_X1A,
+                       chan->address);
+               if (ret < 0)
+                       return ret;
+               *val = ret >> chan->scan_type.shift;
+               return IIO_VAL_INT;
+       case (1 << IIO_CHAN_INFO_SCALE_SEPARATE):
+               /* vout = 4 * vref * dac_code */
+               scale_uv = ad5360_get_channel_vref(st, chan->channel) * 4 * 100;
+               if (scale_uv < 0)
+                       return scale_uv;
+
+               scale_uv >>= (chan->scan_type.realbits);
+               *val =  scale_uv / 100000;
+               *val2 = (scale_uv % 100000) * 10;
+               return IIO_VAL_INT_PLUS_MICRO;
+       case (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE):
+               ret = ad5360_read(indio_dev, AD5360_READBACK_OFFSET,
+                       chan->address);
+               if (ret < 0)
+                       return ret;
+               *val = ret;
+               return IIO_VAL_INT;
+       case (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE):
+               ret = ad5360_read(indio_dev, AD5360_READBACK_GAIN,
+                       chan->address);
+               if (ret < 0)
+                       return ret;
+               *val = ret;
+               return IIO_VAL_INT;
+       case (1 << IIO_CHAN_INFO_OFFSET_SEPARATE):
+               ofs_index = ad5360_get_channel_vref_index(st, chan->channel);
+               ret = ad5360_read(indio_dev, AD5360_READBACK_SF,
+                       AD5360_REG_SF_OFS(ofs_index));
+               if (ret < 0)
+                       return ret;
+
+               ret <<= (chan->scan_type.realbits - 14);
+               *val = -ret;
+               return IIO_VAL_INT;
+       }
+
+       return -EINVAL;
+}
+
+static const struct iio_info ad5360_info = {
+       .read_raw = ad5360_read_raw,
+       .write_raw = ad5360_write_raw,
+       .attrs = &ad5360_attribute_group,
+       .driver_module = THIS_MODULE,
+};
+
+static const char * const ad5360_vref_name[] = {
+        "vref0", "vref1", "vref2"
+};
+
+static int __devinit ad5360_alloc_channels(struct iio_dev *indio_dev)
+{
+       struct ad5360_state *st = iio_priv(indio_dev);
+       struct iio_chan_spec *channels;
+       unsigned int i;
+
+       channels = kcalloc(sizeof(struct iio_chan_spec),
+                       st->chip_info->num_channels, GFP_KERNEL);
+
+       if (!channels)
+               return -ENOMEM;
+
+       for (i = 0; i < st->chip_info->num_channels; ++i) {
+               channels[i] = st->chip_info->channel_template;
+               channels[i].channel = i;
+               channels[i].address = AD5360_CHAN_ADDR(i);
+       }
+
+       indio_dev->channels = channels;
+
+       return 0;
+}
+
+static int __devinit ad5360_probe(struct spi_device *spi)
+{
+       enum ad5360_type type = spi_get_device_id(spi)->driver_data;
+       struct iio_dev *indio_dev;
+       struct ad5360_state *st;
+       unsigned int i;
+       int ret;
+
+       indio_dev = iio_allocate_device(sizeof(*st));
+       if (indio_dev == NULL) {
+               dev_err(&spi->dev, "Failed to allocate iio device\n");
+               return  -ENOMEM;
+       }
+
+       st = iio_priv(indio_dev);
+       spi_set_drvdata(spi, indio_dev);
+
+       st->chip_info = &ad5360_chip_info_tbl[type];
+       st->spi = spi;
+
+       indio_dev->dev.parent = &spi->dev;
+       indio_dev->name = spi_get_device_id(spi)->name;
+       indio_dev->info = &ad5360_info;
+       indio_dev->modes = INDIO_DIRECT_MODE;
+       indio_dev->num_channels = st->chip_info->num_channels;
+
+       ret = ad5360_alloc_channels(indio_dev);
+       if (ret) {
+               dev_err(&spi->dev, "Failed to allocate channel spec: %d\n", ret);
+               goto error_free;
+       }
+
+       for (i = 0; i < st->chip_info->num_vrefs; ++i)
+               st->vref_reg[i].supply = ad5360_vref_name[i];
+
+       ret = regulator_bulk_get(&st->spi->dev, st->chip_info->num_vrefs,
+               st->vref_reg);
+       if (ret) {
+               dev_err(&spi->dev, "Failed to request vref regulators: %d\n", ret);
+               goto error_free_channels;
+       }
+
+       ret = regulator_bulk_enable(st->chip_info->num_vrefs, st->vref_reg);
+       if (ret) {
+               dev_err(&spi->dev, "Failed to enable vref regulators: %d\n", ret);
+               goto error_free_reg;
+       }
+
+       ret = iio_device_register(indio_dev);
+       if (ret) {
+               dev_err(&spi->dev, "Failed to register iio device: %d\n", ret);
+               goto error_disable_reg;
+       }
+
+       return 0;
+
+error_disable_reg:
+       regulator_bulk_disable(st->chip_info->num_vrefs, st->vref_reg);
+error_free_reg:
+       regulator_bulk_free(st->chip_info->num_vrefs, st->vref_reg);
+error_free_channels:
+       kfree(indio_dev->channels);
+error_free:
+       iio_free_device(indio_dev);
+
+       return ret;
+}
+
+static int __devexit ad5360_remove(struct spi_device *spi)
+{
+       struct iio_dev *indio_dev = spi_get_drvdata(spi);
+       struct ad5360_state *st = iio_priv(indio_dev);
+
+       iio_device_unregister(indio_dev);
+
+       kfree(indio_dev->channels);
+
+       regulator_bulk_disable(st->chip_info->num_vrefs, st->vref_reg);
+       regulator_bulk_free(st->chip_info->num_vrefs, st->vref_reg);
+
+       iio_free_device(indio_dev);
+
+       return 0;
+}
+
+static const struct spi_device_id ad5360_ids[] = {
+       { "ad5360", ID_AD5360 },
+       { "ad5361", ID_AD5361 },
+       { "ad5362", ID_AD5362 },
+       { "ad5363", ID_AD5363 },
+       { "ad5370", ID_AD5370 },
+       { "ad5371", ID_AD5371 },
+       { "ad5372", ID_AD5372 },
+       { "ad5373", ID_AD5373 },
+       {}
+};
+MODULE_DEVICE_TABLE(spi, ad5360_ids);
+
+static struct spi_driver ad5360_driver = {
+       .driver = {
+                  .name = "ad5360",
+                  .owner = THIS_MODULE,
+       },
+       .probe = ad5360_probe,
+       .remove = __devexit_p(ad5360_remove),
+       .id_table = ad5360_ids,
+};
+
+static __init int ad5360_spi_init(void)
+{
+       return spi_register_driver(&ad5360_driver);
+}
+module_init(ad5360_spi_init);
+
+static __exit void ad5360_spi_exit(void)
+{
+       spi_unregister_driver(&ad5360_driver);
+}
+module_exit(ad5360_spi_exit);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("Analog Devices AD5360/61/62/63/70/71/72/73 DAC");
+MODULE_LICENSE("GPL v2");