/* * 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 <linux/iio/iio.h> #include <linux/iio/sysfs.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_separate = BIT(IIO_CHAN_INFO_RAW) | \ BIT(IIO_CHAN_INFO_SCALE) | \ BIT(IIO_CHAN_INFO_OFFSET) | \ BIT(IIO_CHAN_INFO_CALIBSCALE) | \ BIT(IIO_CHAN_INFO_CALIBBIAS), \ .scan_type = { \ .sign = 'u', \ .realbits = (bits), \ .storagebits = 16, \ .shift = 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); 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, }, }; 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_transfer(st->spi, t, ARRAY_SIZE(t)); 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_to_iio_dev(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_to_iio_dev(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 IIO_CHAN_INFO_RAW: 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 IIO_CHAN_INFO_CALIBBIAS: 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 IIO_CHAN_INFO_CALIBSCALE: 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 IIO_CHAN_INFO_OFFSET: 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 int ofs_index; int scale_uv; int ret; switch (m) { case IIO_CHAN_INFO_RAW: 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 IIO_CHAN_INFO_SCALE: scale_uv = ad5360_get_channel_vref(st, chan->channel); if (scale_uv < 0) return scale_uv; /* vout = 4 * vref * dac_code */ *val = scale_uv * 4 / 1000; *val2 = chan->scan_type.realbits; return IIO_VAL_FRACTIONAL_LOG2; case IIO_CHAN_INFO_CALIBBIAS: ret = ad5360_read(indio_dev, AD5360_READBACK_OFFSET, chan->address); if (ret < 0) return ret; *val = ret; return IIO_VAL_INT; case IIO_CHAN_INFO_CALIBSCALE: ret = ad5360_read(indio_dev, AD5360_READBACK_GAIN, chan->address); if (ret < 0) return ret; *val = ret; return IIO_VAL_INT; case IIO_CHAN_INFO_OFFSET: 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 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(st->chip_info->num_channels, sizeof(struct iio_chan_spec), 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 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 = devm_iio_device_alloc(&spi->dev, 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); return ret; } for (i = 0; i < st->chip_info->num_vrefs; ++i) st->vref_reg[i].supply = ad5360_vref_name[i]; ret = devm_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_channels; } 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_channels: kfree(indio_dev->channels); return ret; } static int 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); 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", }, .probe = ad5360_probe, .remove = ad5360_remove, .id_table = ad5360_ids, }; module_spi_driver(ad5360_driver); 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");