| /* |
| * AD5415, AD5426, AD5429, AD5432, AD5439, AD5443, AD5449 Digital to Analog |
| * Converter driver. |
| * |
| * Copyright 2012 Analog Devices Inc. |
| * Author: Lars-Peter Clausen <lars@metafoo.de> |
| * |
| * 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 <asm/unaligned.h> |
| |
| #include <linux/iio/iio.h> |
| #include <linux/iio/sysfs.h> |
| |
| #include <linux/platform_data/ad5449.h> |
| |
| #define AD5449_MAX_CHANNELS 2 |
| #define AD5449_MAX_VREFS 2 |
| |
| #define AD5449_CMD_NOOP 0x0 |
| #define AD5449_CMD_LOAD_AND_UPDATE(x) (0x1 + (x) * 3) |
| #define AD5449_CMD_READ(x) (0x2 + (x) * 3) |
| #define AD5449_CMD_LOAD(x) (0x3 + (x) * 3) |
| #define AD5449_CMD_CTRL 13 |
| |
| #define AD5449_CTRL_SDO_OFFSET 10 |
| #define AD5449_CTRL_DAISY_CHAIN BIT(9) |
| #define AD5449_CTRL_HCLR_TO_MIDSCALE BIT(8) |
| #define AD5449_CTRL_SAMPLE_RISING BIT(7) |
| |
| /** |
| * struct ad5449_chip_info - chip specific information |
| * @channels: Channel specification |
| * @num_channels: Number of channels |
| * @has_ctrl: Chip has a control register |
| */ |
| struct ad5449_chip_info { |
| const struct iio_chan_spec *channels; |
| unsigned int num_channels; |
| bool has_ctrl; |
| }; |
| |
| /** |
| * struct ad5449 - driver instance specific data |
| * @spi: the SPI device for this driver instance |
| * @chip_info: chip model specific constants, available modes etc |
| * @vref_reg: vref supply regulators |
| * @has_sdo: whether the SDO line is connected |
| * @dac_cache: Cache for the DAC values |
| * @data: spi transfer buffers |
| */ |
| struct ad5449 { |
| struct spi_device *spi; |
| const struct ad5449_chip_info *chip_info; |
| struct regulator_bulk_data vref_reg[AD5449_MAX_VREFS]; |
| |
| bool has_sdo; |
| uint16_t dac_cache[AD5449_MAX_CHANNELS]; |
| |
| /* |
| * DMA (thus cache coherency maintenance) requires the |
| * transfer buffers to live in their own cache lines. |
| */ |
| __be16 data[2] ____cacheline_aligned; |
| }; |
| |
| enum ad5449_type { |
| ID_AD5426, |
| ID_AD5429, |
| ID_AD5432, |
| ID_AD5439, |
| ID_AD5443, |
| ID_AD5449, |
| }; |
| |
| static int ad5449_write(struct iio_dev *indio_dev, unsigned int addr, |
| unsigned int val) |
| { |
| struct ad5449 *st = iio_priv(indio_dev); |
| int ret; |
| |
| mutex_lock(&indio_dev->mlock); |
| st->data[0] = cpu_to_be16((addr << 12) | val); |
| ret = spi_write(st->spi, st->data, 2); |
| mutex_unlock(&indio_dev->mlock); |
| |
| return ret; |
| } |
| |
| static int ad5449_read(struct iio_dev *indio_dev, unsigned int addr, |
| unsigned int *val) |
| { |
| struct ad5449 *st = iio_priv(indio_dev); |
| int ret; |
| struct spi_message msg; |
| struct spi_transfer t[] = { |
| { |
| .tx_buf = &st->data[0], |
| .len = 2, |
| .cs_change = 1, |
| }, { |
| .tx_buf = &st->data[1], |
| .rx_buf = &st->data[1], |
| .len = 2, |
| }, |
| }; |
| |
| spi_message_init(&msg); |
| spi_message_add_tail(&t[0], &msg); |
| spi_message_add_tail(&t[1], &msg); |
| |
| mutex_lock(&indio_dev->mlock); |
| st->data[0] = cpu_to_be16(addr << 12); |
| st->data[1] = cpu_to_be16(AD5449_CMD_NOOP); |
| |
| ret = spi_sync(st->spi, &msg); |
| if (ret < 0) |
| goto out_unlock; |
| |
| *val = be16_to_cpu(st->data[1]); |
| |
| out_unlock: |
| mutex_unlock(&indio_dev->mlock); |
| return ret; |
| } |
| |
| static int ad5449_read_raw(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, int *val, int *val2, long info) |
| { |
| struct ad5449 *st = iio_priv(indio_dev); |
| struct regulator_bulk_data *reg; |
| int scale_uv; |
| int ret; |
| |
| switch (info) { |
| case IIO_CHAN_INFO_RAW: |
| if (st->has_sdo) { |
| ret = ad5449_read(indio_dev, |
| AD5449_CMD_READ(chan->address), val); |
| if (ret) |
| return ret; |
| *val &= 0xfff; |
| } else { |
| *val = st->dac_cache[chan->address]; |
| } |
| |
| return IIO_VAL_INT; |
| case IIO_CHAN_INFO_SCALE: |
| reg = &st->vref_reg[chan->channel]; |
| scale_uv = regulator_get_voltage(reg->consumer); |
| if (scale_uv < 0) |
| return scale_uv; |
| |
| *val = scale_uv / 1000; |
| *val2 = chan->scan_type.realbits; |
| |
| return IIO_VAL_FRACTIONAL_LOG2; |
| default: |
| break; |
| } |
| |
| return -EINVAL; |
| } |
| |
| static int ad5449_write_raw(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, int val, int val2, long info) |
| { |
| struct ad5449 *st = iio_priv(indio_dev); |
| int ret; |
| |
| switch (info) { |
| case IIO_CHAN_INFO_RAW: |
| if (val < 0 || val >= (1 << chan->scan_type.realbits)) |
| return -EINVAL; |
| |
| ret = ad5449_write(indio_dev, |
| AD5449_CMD_LOAD_AND_UPDATE(chan->address), |
| val << chan->scan_type.shift); |
| if (ret == 0) |
| st->dac_cache[chan->address] = val; |
| break; |
| default: |
| ret = -EINVAL; |
| } |
| |
| return ret; |
| } |
| |
| static const struct iio_info ad5449_info = { |
| .read_raw = ad5449_read_raw, |
| .write_raw = ad5449_write_raw, |
| .driver_module = THIS_MODULE, |
| }; |
| |
| #define AD5449_CHANNEL(chan, bits) { \ |
| .type = IIO_VOLTAGE, \ |
| .indexed = 1, \ |
| .output = 1, \ |
| .channel = (chan), \ |
| .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \ |
| IIO_CHAN_INFO_SCALE_SEPARATE_BIT, \ |
| .address = (chan), \ |
| .scan_type = IIO_ST('u', (bits), 16, 12 - (bits)), \ |
| } |
| |
| #define DECLARE_AD5449_CHANNELS(name, bits) \ |
| const struct iio_chan_spec name[] = { \ |
| AD5449_CHANNEL(0, bits), \ |
| AD5449_CHANNEL(1, bits), \ |
| } |
| |
| static DECLARE_AD5449_CHANNELS(ad5429_channels, 8); |
| static DECLARE_AD5449_CHANNELS(ad5439_channels, 10); |
| static DECLARE_AD5449_CHANNELS(ad5449_channels, 12); |
| |
| static const struct ad5449_chip_info ad5449_chip_info[] = { |
| [ID_AD5426] = { |
| .channels = ad5429_channels, |
| .num_channels = 1, |
| .has_ctrl = false, |
| }, |
| [ID_AD5429] = { |
| .channels = ad5429_channels, |
| .num_channels = 2, |
| .has_ctrl = true, |
| }, |
| [ID_AD5432] = { |
| .channels = ad5439_channels, |
| .num_channels = 1, |
| .has_ctrl = false, |
| }, |
| [ID_AD5439] = { |
| .channels = ad5439_channels, |
| .num_channels = 2, |
| .has_ctrl = true, |
| }, |
| [ID_AD5443] = { |
| .channels = ad5449_channels, |
| .num_channels = 1, |
| .has_ctrl = false, |
| }, |
| [ID_AD5449] = { |
| .channels = ad5449_channels, |
| .num_channels = 2, |
| .has_ctrl = true, |
| }, |
| }; |
| |
| static const char *ad5449_vref_name(struct ad5449 *st, int n) |
| { |
| if (st->chip_info->num_channels == 1) |
| return "VREF"; |
| |
| if (n == 0) |
| return "VREFA"; |
| else |
| return "VREFB"; |
| } |
| |
| static int __devinit ad5449_spi_probe(struct spi_device *spi) |
| { |
| struct ad5449_platform_data *pdata = spi->dev.platform_data; |
| const struct spi_device_id *id = spi_get_device_id(spi); |
| struct iio_dev *indio_dev; |
| struct ad5449 *st; |
| unsigned int i; |
| int ret; |
| |
| indio_dev = iio_device_alloc(sizeof(*st)); |
| if (indio_dev == NULL) |
| return -ENOMEM; |
| |
| st = iio_priv(indio_dev); |
| spi_set_drvdata(spi, indio_dev); |
| |
| st->chip_info = &ad5449_chip_info[id->driver_data]; |
| st->spi = spi; |
| |
| for (i = 0; i < st->chip_info->num_channels; ++i) |
| st->vref_reg[i].supply = ad5449_vref_name(st, i); |
| |
| ret = regulator_bulk_get(&spi->dev, st->chip_info->num_channels, |
| st->vref_reg); |
| if (ret) |
| goto error_free; |
| |
| ret = regulator_bulk_enable(st->chip_info->num_channels, st->vref_reg); |
| if (ret) |
| goto error_free_reg; |
| |
| indio_dev->dev.parent = &spi->dev; |
| indio_dev->name = id->name; |
| indio_dev->info = &ad5449_info; |
| indio_dev->modes = INDIO_DIRECT_MODE; |
| indio_dev->channels = st->chip_info->channels; |
| indio_dev->num_channels = st->chip_info->num_channels; |
| |
| if (st->chip_info->has_ctrl) { |
| unsigned int ctrl = 0x00; |
| if (pdata) { |
| if (pdata->hardware_clear_to_midscale) |
| ctrl |= AD5449_CTRL_HCLR_TO_MIDSCALE; |
| ctrl |= pdata->sdo_mode << AD5449_CTRL_SDO_OFFSET; |
| st->has_sdo = pdata->sdo_mode != AD5449_SDO_DISABLED; |
| } else { |
| st->has_sdo = true; |
| } |
| ad5449_write(indio_dev, AD5449_CMD_CTRL, ctrl); |
| } |
| |
| ret = iio_device_register(indio_dev); |
| if (ret) |
| goto error_disable_reg; |
| |
| return 0; |
| |
| error_disable_reg: |
| regulator_bulk_disable(st->chip_info->num_channels, st->vref_reg); |
| error_free_reg: |
| regulator_bulk_free(st->chip_info->num_channels, st->vref_reg); |
| error_free: |
| iio_device_free(indio_dev); |
| |
| return ret; |
| } |
| |
| static int __devexit ad5449_spi_remove(struct spi_device *spi) |
| { |
| struct iio_dev *indio_dev = spi_get_drvdata(spi); |
| struct ad5449 *st = iio_priv(indio_dev); |
| |
| iio_device_unregister(indio_dev); |
| |
| regulator_bulk_disable(st->chip_info->num_channels, st->vref_reg); |
| regulator_bulk_free(st->chip_info->num_channels, st->vref_reg); |
| |
| iio_device_free(indio_dev); |
| |
| return 0; |
| } |
| |
| static const struct spi_device_id ad5449_spi_ids[] = { |
| { "ad5415", ID_AD5449 }, |
| { "ad5426", ID_AD5426 }, |
| { "ad5429", ID_AD5429 }, |
| { "ad5432", ID_AD5432 }, |
| { "ad5439", ID_AD5439 }, |
| { "ad5443", ID_AD5443 }, |
| { "ad5449", ID_AD5449 }, |
| {} |
| }; |
| MODULE_DEVICE_TABLE(spi, ad5449_spi_ids); |
| |
| static struct spi_driver ad5449_spi_driver = { |
| .driver = { |
| .name = "ad5449", |
| .owner = THIS_MODULE, |
| }, |
| .probe = ad5449_spi_probe, |
| .remove = __devexit_p(ad5449_spi_remove), |
| .id_table = ad5449_spi_ids, |
| }; |
| module_spi_driver(ad5449_spi_driver); |
| |
| MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); |
| MODULE_DESCRIPTION("Analog Devices AD5449 and similar DACs"); |
| MODULE_LICENSE("GPL v2"); |