--- /dev/null
+/*
+ * 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");
projects / GitHub / mt8127 / android_kernel_alcatel_ttab.git / commitdiff