staging:iio:dac: Add AD5064 driver
authorLars-Peter Clausen <lars@metafoo.de>
Tue, 18 Oct 2011 07:33:03 +0000 (09:33 +0200)
committerGreg Kroah-Hartman <gregkh@suse.de>
Wed, 19 Oct 2011 20:50:20 +0000 (13:50 -0700)
This patch adds support for the Analog Devices AD6064, AD6064-1, AD6044, AD6024
quad channel digital-to-analog converter devices.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/staging/iio/dac/Kconfig
drivers/staging/iio/dac/Makefile
drivers/staging/iio/dac/ad5064.c [new file with mode: 0644]

index 30001567ef00813094c06575dba6a76ff60a06e0..724af7fb5b31737ae5dfc53426e7133a42f5aaa5 100644 (file)
@@ -3,6 +3,16 @@
 #
 menu "Digital to analog convertors"
 
+config AD5064
+       tristate "Analog Devices AD5064/64-1/44/24 DAC driver"
+       depends on SPI
+       help
+         Say yes here to build support for Analog Devices AD5064, AD5064-1,
+         AD5044, AD5024 Digital to Analog Converter.
+
+         To compile this driver as a module, choose M here: the
+         module will be called ad5064.
+
 config AD5624R_SPI
        tristate "Analog Devices AD5624/44/64R DAC spi driver"
        depends on SPI
index 7f4f2ed031ec534d900f42e737155a7f97713336..ea4975031fed98f435e3fa41c5c2f248eafa631d 100644 (file)
@@ -3,6 +3,7 @@
 #
 
 obj-$(CONFIG_AD5624R_SPI) += ad5624r_spi.o
+obj-$(CONFIG_AD5064) += ad5064.o
 obj-$(CONFIG_AD5504) += ad5504.o
 obj-$(CONFIG_AD5446) += ad5446.o
 obj-$(CONFIG_AD5791) += ad5791.o
diff --git a/drivers/staging/iio/dac/ad5064.c b/drivers/staging/iio/dac/ad5064.c
new file mode 100644 (file)
index 0000000..24279f2
--- /dev/null
@@ -0,0 +1,463 @@
+/*
+ * AD5064, AD5064-1, AD5044, AD5024 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 AD5064_DAC_CHANNELS                    4
+
+#define AD5064_ADDR(x)                         ((x) << 20)
+#define AD5064_CMD(x)                          ((x) << 24)
+
+#define AD5064_ADDR_DAC(chan)                  (chan)
+#define AD5064_ADDR_ALL_DAC                    0xF
+
+#define AD5064_CMD_WRITE_INPUT_N               0x0
+#define AD5064_CMD_UPDATE_DAC_N                        0x1
+#define AD5064_CMD_WRITE_INPUT_N_UPDATE_ALL    0x2
+#define AD5064_CMD_WRITE_INPUT_N_UPDATE_N      0x3
+#define AD5064_CMD_POWERDOWN_DAC               0x4
+#define AD5064_CMD_CLEAR                       0x5
+#define AD5064_CMD_LDAC_MASK                   0x6
+#define AD5064_CMD_RESET                       0x7
+#define AD5064_CMD_DAISY_CHAIN_ENABLE          0x8
+
+#define AD5064_LDAC_PWRDN_NONE                 0x0
+#define AD5064_LDAC_PWRDN_1K                   0x1
+#define AD5064_LDAC_PWRDN_100K                 0x2
+#define AD5064_LDAC_PWRDN_3STATE               0x3
+
+/**
+ * struct ad5064_chip_info - chip specific information
+ * @shared_vref:       whether the vref supply is shared between channels
+ * @channel:           channel specification
+*/
+
+struct ad5064_chip_info {
+       bool shared_vref;
+       struct iio_chan_spec channel[AD5064_DAC_CHANNELS];
+};
+
+/**
+ * struct ad5064_state - driver instance specific data
+ * @spi:               spi_device
+ * @chip_info:         chip model specific constants, available modes etc
+ * @vref_reg:          vref supply regulators
+ * @pwr_down:          whether channel is powered down
+ * @pwr_down_mode:     channel's current power down mode
+ * @dac_cache:         current DAC raw value (chip does not support readback)
+ * @data:              spi transfer buffers
+ */
+
+struct ad5064_state {
+       struct spi_device               *spi;
+       const struct ad5064_chip_info   *chip_info;
+       struct regulator_bulk_data      vref_reg[AD5064_DAC_CHANNELS];
+       bool                            pwr_down[AD5064_DAC_CHANNELS];
+       u8                              pwr_down_mode[AD5064_DAC_CHANNELS];
+       unsigned int                    dac_cache[AD5064_DAC_CHANNELS];
+
+       /*
+        * DMA (thus cache coherency maintenance) requires the
+        * transfer buffers to live in their own cache lines.
+        */
+       __be32 data ____cacheline_aligned;
+};
+
+enum ad5064_type {
+       ID_AD5024,
+       ID_AD5044,
+       ID_AD5064,
+       ID_AD5064_1,
+};
+
+#define AD5064_CHANNEL(chan, bits) {                           \
+       .type = IIO_VOLTAGE,                                    \
+       .indexed = 1,                                           \
+       .output = 1,                                            \
+       .channel = (chan),                                      \
+       .info_mask = (1 << IIO_CHAN_INFO_SCALE_SEPARATE),       \
+       .address = AD5064_ADDR_DAC(chan),                       \
+       .scan_type = IIO_ST('u', (bits), 16, 20 - (bits))       \
+}
+
+static const struct ad5064_chip_info ad5064_chip_info_tbl[] = {
+       [ID_AD5024] = {
+               .shared_vref = false,
+               .channel[0] = AD5064_CHANNEL(0, 12),
+               .channel[1] = AD5064_CHANNEL(1, 12),
+               .channel[2] = AD5064_CHANNEL(2, 12),
+               .channel[3] = AD5064_CHANNEL(3, 12),
+       },
+       [ID_AD5044] = {
+               .shared_vref = false,
+               .channel[0] = AD5064_CHANNEL(0, 14),
+               .channel[1] = AD5064_CHANNEL(1, 14),
+               .channel[2] = AD5064_CHANNEL(2, 14),
+               .channel[3] = AD5064_CHANNEL(3, 14),
+       },
+       [ID_AD5064] = {
+               .shared_vref = false,
+               .channel[0] = AD5064_CHANNEL(0, 16),
+               .channel[1] = AD5064_CHANNEL(1, 16),
+               .channel[2] = AD5064_CHANNEL(2, 16),
+               .channel[3] = AD5064_CHANNEL(3, 16),
+       },
+       [ID_AD5064_1] = {
+               .shared_vref = true,
+               .channel[0] = AD5064_CHANNEL(0, 16),
+               .channel[1] = AD5064_CHANNEL(1, 16),
+               .channel[2] = AD5064_CHANNEL(2, 16),
+               .channel[3] = AD5064_CHANNEL(3, 16),
+       },
+};
+
+static int ad5064_spi_write(struct ad5064_state *st, unsigned int cmd,
+       unsigned int addr, unsigned int val, unsigned int shift)
+{
+       val <<= shift;
+
+       st->data = cpu_to_be32(AD5064_CMD(cmd) | AD5064_ADDR(addr) | val);
+
+       return spi_write(st->spi, &st->data, sizeof(st->data));
+}
+
+static int ad5064_sync_powerdown_mode(struct ad5064_state *st,
+       unsigned int channel)
+{
+       unsigned int val;
+       int ret;
+
+       val = (0x1 << channel);
+
+       if (st->pwr_down[channel])
+               val |= st->pwr_down_mode[channel] << 8;
+
+       ret = ad5064_spi_write(st, AD5064_CMD_POWERDOWN_DAC, 0, val, 0);
+
+       return ret;
+}
+
+static const char ad5064_powerdown_modes[][15] = {
+       [AD5064_LDAC_PWRDN_NONE]        = "",
+       [AD5064_LDAC_PWRDN_1K]          = "1kohm_to_gnd",
+       [AD5064_LDAC_PWRDN_100K]        = "100kohm_to_gnd",
+       [AD5064_LDAC_PWRDN_3STATE]      = "three_state",
+};
+
+static ssize_t ad5064_read_powerdown_mode(struct device *dev,
+       struct device_attribute *attr, char *buf)
+{
+       struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+       struct iio_dev *indio_dev = dev_get_drvdata(dev);
+       struct ad5064_state *st = iio_priv(indio_dev);
+
+       return sprintf(buf, "%s\n",
+               ad5064_powerdown_modes[st->pwr_down_mode[this_attr->address]]);
+}
+
+static ssize_t ad5064_write_powerdown_mode(struct device *dev,
+       struct device_attribute *attr, const char *buf, size_t len)
+{
+       struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+       struct iio_dev *indio_dev = dev_get_drvdata(dev);
+       struct ad5064_state *st = iio_priv(indio_dev);
+       unsigned int mode, i;
+       int ret;
+
+       mode = 0;
+
+       for (i = 1; i < ARRAY_SIZE(ad5064_powerdown_modes); ++i) {
+               if (sysfs_streq(buf, ad5064_powerdown_modes[i])) {
+                       mode = i;
+                       break;
+               }
+       }
+       if (mode == 0)
+               return  -EINVAL;
+
+       mutex_lock(&indio_dev->mlock);
+       st->pwr_down_mode[this_attr->address] = mode;
+
+       ret = ad5064_sync_powerdown_mode(st, this_attr->address);
+       mutex_unlock(&indio_dev->mlock);
+
+       return ret ? ret : len;
+}
+
+static ssize_t ad5064_read_dac_powerdown(struct device *dev,
+                                          struct device_attribute *attr,
+                                          char *buf)
+{
+       struct iio_dev *indio_dev = dev_get_drvdata(dev);
+       struct ad5064_state *st = iio_priv(indio_dev);
+       struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+
+       return sprintf(buf, "%d\n", st->pwr_down[this_attr->address]);
+}
+
+static ssize_t ad5064_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);
+       struct ad5064_state *st = iio_priv(indio_dev);
+       struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+       bool pwr_down;
+       int ret;
+
+       ret = strtobool(buf, &pwr_down);
+       if (ret)
+               return ret;
+
+       mutex_lock(&indio_dev->mlock);
+       st->pwr_down[this_attr->address] = pwr_down;
+
+       ret = ad5064_sync_powerdown_mode(st, this_attr->address);
+       mutex_unlock(&indio_dev->mlock);
+       return ret ? ret : len;
+}
+
+static IIO_CONST_ATTR(out_voltage_powerdown_mode_available,
+                       "1kohm_to_gnd 100kohm_to_gnd three_state");
+
+#define IIO_DEV_ATTR_DAC_POWERDOWN_MODE(_chan) \
+       IIO_DEVICE_ATTR(out_voltage##_chan##_powerdown_mode, \
+                       S_IRUGO | S_IWUSR, \
+                       ad5064_read_powerdown_mode, \
+                       ad5064_write_powerdown_mode, _chan);
+
+#define IIO_DEV_ATTR_DAC_POWERDOWN(_chan)                              \
+       IIO_DEVICE_ATTR(out_voltage##_chan##_powerdown,                 \
+                       S_IRUGO | S_IWUSR,                              \
+                       ad5064_read_dac_powerdown,                      \
+                       ad5064_write_dac_powerdown, _chan)
+
+static IIO_DEV_ATTR_DAC_POWERDOWN(0);
+static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(0);
+static IIO_DEV_ATTR_DAC_POWERDOWN(1);
+static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(1);
+static IIO_DEV_ATTR_DAC_POWERDOWN(2);
+static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(2);
+static IIO_DEV_ATTR_DAC_POWERDOWN(3);
+static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(3);
+
+static struct attribute *ad5064_attributes[] = {
+       &iio_dev_attr_out_voltage0_powerdown.dev_attr.attr,
+       &iio_dev_attr_out_voltage1_powerdown.dev_attr.attr,
+       &iio_dev_attr_out_voltage2_powerdown.dev_attr.attr,
+       &iio_dev_attr_out_voltage3_powerdown.dev_attr.attr,
+       &iio_dev_attr_out_voltage0_powerdown_mode.dev_attr.attr,
+       &iio_dev_attr_out_voltage1_powerdown_mode.dev_attr.attr,
+       &iio_dev_attr_out_voltage2_powerdown_mode.dev_attr.attr,
+       &iio_dev_attr_out_voltage3_powerdown_mode.dev_attr.attr,
+       &iio_const_attr_out_voltage_powerdown_mode_available.dev_attr.attr,
+       NULL,
+};
+
+static const struct attribute_group ad5064_attribute_group = {
+       .attrs = ad5064_attributes,
+};
+
+static int ad5064_read_raw(struct iio_dev *indio_dev,
+                          struct iio_chan_spec const *chan,
+                          int *val,
+                          int *val2,
+                          long m)
+{
+       struct ad5064_state *st = iio_priv(indio_dev);
+       unsigned long scale_uv;
+       unsigned int vref;
+
+       switch (m) {
+       case 0:
+               *val = st->dac_cache[chan->channel];
+               return IIO_VAL_INT;
+       case (1 << IIO_CHAN_INFO_SCALE_SEPARATE):
+               vref = st->chip_info->shared_vref ? 0 : chan->channel;
+               scale_uv = regulator_get_voltage(st->vref_reg[vref].consumer);
+               if (scale_uv < 0)
+                       return scale_uv;
+
+               scale_uv = (scale_uv * 100) >> chan->scan_type.realbits;
+               *val =  scale_uv / 100000;
+               *val2 = (scale_uv % 100000) * 10;
+               return IIO_VAL_INT_PLUS_MICRO;
+       default:
+               break;
+       }
+       return -EINVAL;
+}
+
+static int ad5064_write_raw(struct iio_dev *indio_dev,
+       struct iio_chan_spec const *chan, int val, int val2, long mask)
+{
+       struct ad5064_state *st = iio_priv(indio_dev);
+       int ret;
+
+       switch (mask) {
+       case 0:
+               if (val > (1 << chan->scan_type.realbits) || val < 0)
+                       return -EINVAL;
+
+               mutex_lock(&indio_dev->mlock);
+               ret = ad5064_spi_write(st, AD5064_CMD_WRITE_INPUT_N_UPDATE_N,
+                               chan->address, val, chan->scan_type.shift);
+               if (ret == 0)
+                       st->dac_cache[chan->channel] = val;
+               mutex_unlock(&indio_dev->mlock);
+               break;
+       default:
+               ret = -EINVAL;
+       }
+
+       return ret;
+}
+
+static const struct iio_info ad5064_info = {
+       .read_raw = ad5064_read_raw,
+       .write_raw = ad5064_write_raw,
+       .attrs = &ad5064_attribute_group,
+       .driver_module = THIS_MODULE,
+};
+
+static inline unsigned int ad5064_num_vref(struct ad5064_state *st)
+{
+       return st->chip_info->shared_vref ? 1 : AD5064_DAC_CHANNELS;
+}
+
+static const char * const ad5064_vref_names[] = {
+       "vrefA",
+       "vrefB",
+       "vrefC",
+       "vrefD",
+};
+
+static const char * const ad5064_vref_name(struct ad5064_state *st,
+       unsigned int vref)
+{
+       return st->chip_info->shared_vref ? "vref" : ad5064_vref_names[vref];
+}
+
+static int __devinit ad5064_probe(struct spi_device *spi)
+{
+       enum ad5064_type type = spi_get_device_id(spi)->driver_data;
+       struct iio_dev *indio_dev;
+       struct ad5064_state *st;
+       unsigned int i;
+       int ret;
+
+       indio_dev = iio_allocate_device(sizeof(*st));
+       if (indio_dev == NULL)
+               return  -ENOMEM;
+
+       st = iio_priv(indio_dev);
+       spi_set_drvdata(spi, indio_dev);
+
+       st->chip_info = &ad5064_chip_info_tbl[type];
+       st->spi = spi;
+
+       for (i = 0; i < ad5064_num_vref(st); ++i)
+               st->vref_reg[i].supply = ad5064_vref_name(st, i);
+
+       ret = regulator_bulk_get(&st->spi->dev, ad5064_num_vref(st),
+               st->vref_reg);
+       if (ret)
+               goto error_free;
+
+       ret = regulator_bulk_enable(ad5064_num_vref(st), st->vref_reg);
+       if (ret)
+               goto error_free_reg;
+
+       for (i = 0; i < AD5064_DAC_CHANNELS; ++i) {
+               st->pwr_down_mode[i] = AD5064_LDAC_PWRDN_1K;
+               st->dac_cache[i] = 0x8000;
+       }
+
+       indio_dev->dev.parent = &spi->dev;
+       indio_dev->name = spi_get_device_id(spi)->name;
+       indio_dev->info = &ad5064_info;
+       indio_dev->modes = INDIO_DIRECT_MODE;
+       indio_dev->channels = st->chip_info->channel;
+       indio_dev->num_channels = AD5064_DAC_CHANNELS;
+
+       ret = iio_device_register(indio_dev);
+       if (ret)
+               goto error_disable_reg;
+
+       return 0;
+
+error_disable_reg:
+       regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg);
+error_free_reg:
+       regulator_bulk_free(ad5064_num_vref(st), st->vref_reg);
+error_free:
+       iio_free_device(indio_dev);
+
+       return ret;
+}
+
+
+static int __devexit ad5064_remove(struct spi_device *spi)
+{
+       struct iio_dev *indio_dev = spi_get_drvdata(spi);
+       struct ad5064_state *st = iio_priv(indio_dev);
+
+       iio_device_unregister(indio_dev);
+
+       regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg);
+       regulator_bulk_free(ad5064_num_vref(st), st->vref_reg);
+
+       iio_free_device(indio_dev);
+
+       return 0;
+}
+
+static const struct spi_device_id ad5064_id[] = {
+       {"ad5024", ID_AD5024},
+       {"ad5044", ID_AD5044},
+       {"ad5064", ID_AD5064},
+       {"ad5064-1", ID_AD5064_1},
+       {}
+};
+MODULE_DEVICE_TABLE(spi, ad5064_id);
+
+static struct spi_driver ad5064_driver = {
+       .driver = {
+                  .name = "ad5064",
+                  .owner = THIS_MODULE,
+       },
+       .probe = ad5064_probe,
+       .remove = __devexit_p(ad5064_remove),
+       .id_table = ad5064_id,
+};
+
+static __init int ad5064_spi_init(void)
+{
+       return spi_register_driver(&ad5064_driver);
+}
+module_init(ad5064_spi_init);
+
+static __exit void ad5064_spi_exit(void)
+{
+       spi_unregister_driver(&ad5064_driver);
+}
+module_exit(ad5064_spi_exit);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("Analog Devices AD5064/64-1/44/24 DAC");
+MODULE_LICENSE("GPL v2");