diff options
Diffstat (limited to 'drivers/iio/dac/ad5064.c')
| -rw-r--r-- | drivers/iio/dac/ad5064.c | 684 | 
1 files changed, 684 insertions, 0 deletions
diff --git a/drivers/iio/dac/ad5064.c b/drivers/iio/dac/ad5064.c new file mode 100644 index 00000000000..f03b92fd380 --- /dev/null +++ b/drivers/iio/dac/ad5064.c @@ -0,0 +1,684 @@ +/* + * AD5024, AD5025, AD5044, AD5045, AD5064, AD5064-1, AD5065, AD5628, AD5629R, + * AD5648, AD5666, AD5668, AD5669R 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/i2c.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> + +#define AD5064_MAX_DAC_CHANNELS			8 +#define AD5064_MAX_VREFS			4 + +#define AD5064_ADDR(x)				((x) << 20) +#define AD5064_CMD(x)				((x) << 24) + +#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_CONFIG			0x8 + +#define AD5064_CONFIG_DAISY_CHAIN_ENABLE	BIT(1) +#define AD5064_CONFIG_INT_VREF_ENABLE		BIT(0) + +#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 + * @internal_vref:	internal reference voltage. 0 if the chip has no internal + *			vref. + * @channel:		channel specification + * @num_channels:	number of channels + */ + +struct ad5064_chip_info { +	bool shared_vref; +	unsigned long internal_vref; +	const struct iio_chan_spec *channels; +	unsigned int num_channels; +}; + +struct ad5064_state; + +typedef int (*ad5064_write_func)(struct ad5064_state *st, unsigned int cmd, +		unsigned int addr, unsigned int val); + +/** + * struct ad5064_state - driver instance specific data + * @dev:		the device for this driver instance + * @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) + * @use_internal_vref:	set to true if the internal reference voltage should be + *			used. + * @write:		register write callback + * @data:		i2c/spi transfer buffers + */ + +struct ad5064_state { +	struct device			*dev; +	const struct ad5064_chip_info	*chip_info; +	struct regulator_bulk_data	vref_reg[AD5064_MAX_VREFS]; +	bool				pwr_down[AD5064_MAX_DAC_CHANNELS]; +	u8				pwr_down_mode[AD5064_MAX_DAC_CHANNELS]; +	unsigned int			dac_cache[AD5064_MAX_DAC_CHANNELS]; +	bool				use_internal_vref; + +	ad5064_write_func		write; + +	/* +	 * DMA (thus cache coherency maintenance) requires the +	 * transfer buffers to live in their own cache lines. +	 */ +	union { +		u8 i2c[3]; +		__be32 spi; +	} data ____cacheline_aligned; +}; + +enum ad5064_type { +	ID_AD5024, +	ID_AD5025, +	ID_AD5044, +	ID_AD5045, +	ID_AD5064, +	ID_AD5064_1, +	ID_AD5065, +	ID_AD5628_1, +	ID_AD5628_2, +	ID_AD5648_1, +	ID_AD5648_2, +	ID_AD5666_1, +	ID_AD5666_2, +	ID_AD5668_1, +	ID_AD5668_2, +}; + +static int ad5064_write(struct ad5064_state *st, unsigned int cmd, +	unsigned int addr, unsigned int val, unsigned int shift) +{ +	val <<= shift; + +	return st->write(st, cmd, addr, val); +} + +static int ad5064_sync_powerdown_mode(struct ad5064_state *st, +	const struct iio_chan_spec *chan) +{ +	unsigned int val; +	int ret; + +	val = (0x1 << chan->address); + +	if (st->pwr_down[chan->channel]) +		val |= st->pwr_down_mode[chan->channel] << 8; + +	ret = ad5064_write(st, AD5064_CMD_POWERDOWN_DAC, 0, val, 0); + +	return ret; +} + +static const char * const ad5064_powerdown_modes[] = { +	"1kohm_to_gnd", +	"100kohm_to_gnd", +	"three_state", +}; + +static int ad5064_get_powerdown_mode(struct iio_dev *indio_dev, +	const struct iio_chan_spec *chan) +{ +	struct ad5064_state *st = iio_priv(indio_dev); + +	return st->pwr_down_mode[chan->channel] - 1; +} + +static int ad5064_set_powerdown_mode(struct iio_dev *indio_dev, +	const struct iio_chan_spec *chan, unsigned int mode) +{ +	struct ad5064_state *st = iio_priv(indio_dev); +	int ret; + +	mutex_lock(&indio_dev->mlock); +	st->pwr_down_mode[chan->channel] = mode + 1; + +	ret = ad5064_sync_powerdown_mode(st, chan); +	mutex_unlock(&indio_dev->mlock); + +	return ret; +} + +static const struct iio_enum ad5064_powerdown_mode_enum = { +	.items = ad5064_powerdown_modes, +	.num_items = ARRAY_SIZE(ad5064_powerdown_modes), +	.get = ad5064_get_powerdown_mode, +	.set = ad5064_set_powerdown_mode, +}; + +static ssize_t ad5064_read_dac_powerdown(struct iio_dev *indio_dev, +	uintptr_t private, const struct iio_chan_spec *chan, char *buf) +{ +	struct ad5064_state *st = iio_priv(indio_dev); + +	return sprintf(buf, "%d\n", st->pwr_down[chan->channel]); +} + +static ssize_t ad5064_write_dac_powerdown(struct iio_dev *indio_dev, +	 uintptr_t private, const struct iio_chan_spec *chan, const char *buf, +	 size_t len) +{ +	struct ad5064_state *st = iio_priv(indio_dev); +	bool pwr_down; +	int ret; + +	ret = strtobool(buf, &pwr_down); +	if (ret) +		return ret; + +	mutex_lock(&indio_dev->mlock); +	st->pwr_down[chan->channel] = pwr_down; + +	ret = ad5064_sync_powerdown_mode(st, chan); +	mutex_unlock(&indio_dev->mlock); +	return ret ? ret : len; +} + +static int ad5064_get_vref(struct ad5064_state *st, +	struct iio_chan_spec const *chan) +{ +	unsigned int i; + +	if (st->use_internal_vref) +		return st->chip_info->internal_vref; + +	i = st->chip_info->shared_vref ? 0 : chan->channel; +	return regulator_get_voltage(st->vref_reg[i].consumer); +} + +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); +	int scale_uv; + +	switch (m) { +	case IIO_CHAN_INFO_RAW: +		*val = st->dac_cache[chan->channel]; +		return IIO_VAL_INT; +	case IIO_CHAN_INFO_SCALE: +		scale_uv = ad5064_get_vref(st, chan); +		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 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 IIO_CHAN_INFO_RAW: +		if (val >= (1 << chan->scan_type.realbits) || val < 0) +			return -EINVAL; + +		mutex_lock(&indio_dev->mlock); +		ret = ad5064_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, +	.driver_module = THIS_MODULE, +}; + +static const struct iio_chan_spec_ext_info ad5064_ext_info[] = { +	{ +		.name = "powerdown", +		.read = ad5064_read_dac_powerdown, +		.write = ad5064_write_dac_powerdown, +		.shared = IIO_SEPARATE, +	}, +	IIO_ENUM("powerdown_mode", IIO_SEPARATE, &ad5064_powerdown_mode_enum), +	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5064_powerdown_mode_enum), +	{ }, +}; + +#define AD5064_CHANNEL(chan, addr, bits) {			\ +	.type = IIO_VOLTAGE,					\ +	.indexed = 1,						\ +	.output = 1,						\ +	.channel = (chan),					\ +	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\ +	BIT(IIO_CHAN_INFO_SCALE),					\ +	.address = addr,					\ +	.scan_type = {						\ +		.sign = 'u',					\ +		.realbits = (bits),				\ +		.storagebits = 16,				\ +		.shift = 20 - bits,				\ +	},							\ +	.ext_info = ad5064_ext_info,				\ +} + +#define DECLARE_AD5064_CHANNELS(name, bits) \ +const struct iio_chan_spec name[] = { \ +	AD5064_CHANNEL(0, 0, bits), \ +	AD5064_CHANNEL(1, 1, bits), \ +	AD5064_CHANNEL(2, 2, bits), \ +	AD5064_CHANNEL(3, 3, bits), \ +	AD5064_CHANNEL(4, 4, bits), \ +	AD5064_CHANNEL(5, 5, bits), \ +	AD5064_CHANNEL(6, 6, bits), \ +	AD5064_CHANNEL(7, 7, bits), \ +} + +#define DECLARE_AD5065_CHANNELS(name, bits) \ +const struct iio_chan_spec name[] = { \ +	AD5064_CHANNEL(0, 0, bits), \ +	AD5064_CHANNEL(1, 3, bits), \ +} + +static DECLARE_AD5064_CHANNELS(ad5024_channels, 12); +static DECLARE_AD5064_CHANNELS(ad5044_channels, 14); +static DECLARE_AD5064_CHANNELS(ad5064_channels, 16); + +static DECLARE_AD5065_CHANNELS(ad5025_channels, 12); +static DECLARE_AD5065_CHANNELS(ad5045_channels, 14); +static DECLARE_AD5065_CHANNELS(ad5065_channels, 16); + +static const struct ad5064_chip_info ad5064_chip_info_tbl[] = { +	[ID_AD5024] = { +		.shared_vref = false, +		.channels = ad5024_channels, +		.num_channels = 4, +	}, +	[ID_AD5025] = { +		.shared_vref = false, +		.channels = ad5025_channels, +		.num_channels = 2, +	}, +	[ID_AD5044] = { +		.shared_vref = false, +		.channels = ad5044_channels, +		.num_channels = 4, +	}, +	[ID_AD5045] = { +		.shared_vref = false, +		.channels = ad5045_channels, +		.num_channels = 2, +	}, +	[ID_AD5064] = { +		.shared_vref = false, +		.channels = ad5064_channels, +		.num_channels = 4, +	}, +	[ID_AD5064_1] = { +		.shared_vref = true, +		.channels = ad5064_channels, +		.num_channels = 4, +	}, +	[ID_AD5065] = { +		.shared_vref = false, +		.channels = ad5065_channels, +		.num_channels = 2, +	}, +	[ID_AD5628_1] = { +		.shared_vref = true, +		.internal_vref = 2500000, +		.channels = ad5024_channels, +		.num_channels = 8, +	}, +	[ID_AD5628_2] = { +		.shared_vref = true, +		.internal_vref = 5000000, +		.channels = ad5024_channels, +		.num_channels = 8, +	}, +	[ID_AD5648_1] = { +		.shared_vref = true, +		.internal_vref = 2500000, +		.channels = ad5044_channels, +		.num_channels = 8, +	}, +	[ID_AD5648_2] = { +		.shared_vref = true, +		.internal_vref = 5000000, +		.channels = ad5044_channels, +		.num_channels = 8, +	}, +	[ID_AD5666_1] = { +		.shared_vref = true, +		.internal_vref = 2500000, +		.channels = ad5064_channels, +		.num_channels = 4, +	}, +	[ID_AD5666_2] = { +		.shared_vref = true, +		.internal_vref = 5000000, +		.channels = ad5064_channels, +		.num_channels = 4, +	}, +	[ID_AD5668_1] = { +		.shared_vref = true, +		.internal_vref = 2500000, +		.channels = ad5064_channels, +		.num_channels = 8, +	}, +	[ID_AD5668_2] = { +		.shared_vref = true, +		.internal_vref = 5000000, +		.channels = ad5064_channels, +		.num_channels = 8, +	}, +}; + +static inline unsigned int ad5064_num_vref(struct ad5064_state *st) +{ +	return st->chip_info->shared_vref ? 1 : st->chip_info->num_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 ad5064_probe(struct device *dev, enum ad5064_type type, +			const char *name, ad5064_write_func write) +{ +	struct iio_dev *indio_dev; +	struct ad5064_state *st; +	unsigned int midscale; +	unsigned int i; +	int ret; + +	indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); +	if (indio_dev == NULL) +		return  -ENOMEM; + +	st = iio_priv(indio_dev); +	dev_set_drvdata(dev, indio_dev); + +	st->chip_info = &ad5064_chip_info_tbl[type]; +	st->dev = dev; +	st->write = write; + +	for (i = 0; i < ad5064_num_vref(st); ++i) +		st->vref_reg[i].supply = ad5064_vref_name(st, i); + +	ret = devm_regulator_bulk_get(dev, ad5064_num_vref(st), +		st->vref_reg); +	if (ret) { +		if (!st->chip_info->internal_vref) +			return ret; +		st->use_internal_vref = true; +		ret = ad5064_write(st, AD5064_CMD_CONFIG, 0, +			AD5064_CONFIG_INT_VREF_ENABLE, 0); +		if (ret) { +			dev_err(dev, "Failed to enable internal vref: %d\n", +				ret); +			return ret; +		} +	} else { +		ret = regulator_bulk_enable(ad5064_num_vref(st), st->vref_reg); +		if (ret) +			return ret; +	} + +	indio_dev->dev.parent = dev; +	indio_dev->name = name; +	indio_dev->info = &ad5064_info; +	indio_dev->modes = INDIO_DIRECT_MODE; +	indio_dev->channels = st->chip_info->channels; +	indio_dev->num_channels = st->chip_info->num_channels; + +	midscale = (1 << indio_dev->channels[0].scan_type.realbits) /  2; + +	for (i = 0; i < st->chip_info->num_channels; ++i) { +		st->pwr_down_mode[i] = AD5064_LDAC_PWRDN_1K; +		st->dac_cache[i] = midscale; +	} + +	ret = iio_device_register(indio_dev); +	if (ret) +		goto error_disable_reg; + +	return 0; + +error_disable_reg: +	if (!st->use_internal_vref) +		regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg); + +	return ret; +} + +static int ad5064_remove(struct device *dev) +{ +	struct iio_dev *indio_dev = dev_get_drvdata(dev); +	struct ad5064_state *st = iio_priv(indio_dev); + +	iio_device_unregister(indio_dev); + +	if (!st->use_internal_vref) +		regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg); + +	return 0; +} + +#if IS_ENABLED(CONFIG_SPI_MASTER) + +static int ad5064_spi_write(struct ad5064_state *st, unsigned int cmd, +	unsigned int addr, unsigned int val) +{ +	struct spi_device *spi = to_spi_device(st->dev); + +	st->data.spi = cpu_to_be32(AD5064_CMD(cmd) | AD5064_ADDR(addr) | val); +	return spi_write(spi, &st->data.spi, sizeof(st->data.spi)); +} + +static int ad5064_spi_probe(struct spi_device *spi) +{ +	const struct spi_device_id *id = spi_get_device_id(spi); + +	return ad5064_probe(&spi->dev, id->driver_data, id->name, +				ad5064_spi_write); +} + +static int ad5064_spi_remove(struct spi_device *spi) +{ +	return ad5064_remove(&spi->dev); +} + +static const struct spi_device_id ad5064_spi_ids[] = { +	{"ad5024", ID_AD5024}, +	{"ad5025", ID_AD5025}, +	{"ad5044", ID_AD5044}, +	{"ad5045", ID_AD5045}, +	{"ad5064", ID_AD5064}, +	{"ad5064-1", ID_AD5064_1}, +	{"ad5065", ID_AD5065}, +	{"ad5628-1", ID_AD5628_1}, +	{"ad5628-2", ID_AD5628_2}, +	{"ad5648-1", ID_AD5648_1}, +	{"ad5648-2", ID_AD5648_2}, +	{"ad5666-1", ID_AD5666_1}, +	{"ad5666-2", ID_AD5666_2}, +	{"ad5668-1", ID_AD5668_1}, +	{"ad5668-2", ID_AD5668_2}, +	{"ad5668-3", ID_AD5668_2}, /* similar enough to ad5668-2 */ +	{} +}; +MODULE_DEVICE_TABLE(spi, ad5064_spi_ids); + +static struct spi_driver ad5064_spi_driver = { +	.driver = { +		   .name = "ad5064", +		   .owner = THIS_MODULE, +	}, +	.probe = ad5064_spi_probe, +	.remove = ad5064_spi_remove, +	.id_table = ad5064_spi_ids, +}; + +static int __init ad5064_spi_register_driver(void) +{ +	return spi_register_driver(&ad5064_spi_driver); +} + +static void ad5064_spi_unregister_driver(void) +{ +	spi_unregister_driver(&ad5064_spi_driver); +} + +#else + +static inline int ad5064_spi_register_driver(void) { return 0; } +static inline void ad5064_spi_unregister_driver(void) { } + +#endif + +#if IS_ENABLED(CONFIG_I2C) + +static int ad5064_i2c_write(struct ad5064_state *st, unsigned int cmd, +	unsigned int addr, unsigned int val) +{ +	struct i2c_client *i2c = to_i2c_client(st->dev); + +	st->data.i2c[0] = (cmd << 4) | addr; +	put_unaligned_be16(val, &st->data.i2c[1]); +	return i2c_master_send(i2c, st->data.i2c, 3); +} + +static int ad5064_i2c_probe(struct i2c_client *i2c, +	const struct i2c_device_id *id) +{ +	return ad5064_probe(&i2c->dev, id->driver_data, id->name, +						ad5064_i2c_write); +} + +static int ad5064_i2c_remove(struct i2c_client *i2c) +{ +	return ad5064_remove(&i2c->dev); +} + +static const struct i2c_device_id ad5064_i2c_ids[] = { +	{"ad5629-1", ID_AD5628_1}, +	{"ad5629-2", ID_AD5628_2}, +	{"ad5629-3", ID_AD5628_2}, /* similar enough to ad5629-2 */ +	{"ad5669-1", ID_AD5668_1}, +	{"ad5669-2", ID_AD5668_2}, +	{"ad5669-3", ID_AD5668_2}, /* similar enough to ad5669-2 */ +	{} +}; +MODULE_DEVICE_TABLE(i2c, ad5064_i2c_ids); + +static struct i2c_driver ad5064_i2c_driver = { +	.driver = { +		   .name = "ad5064", +		   .owner = THIS_MODULE, +	}, +	.probe = ad5064_i2c_probe, +	.remove = ad5064_i2c_remove, +	.id_table = ad5064_i2c_ids, +}; + +static int __init ad5064_i2c_register_driver(void) +{ +	return i2c_add_driver(&ad5064_i2c_driver); +} + +static void __exit ad5064_i2c_unregister_driver(void) +{ +	i2c_del_driver(&ad5064_i2c_driver); +} + +#else + +static inline int ad5064_i2c_register_driver(void) { return 0; } +static inline void ad5064_i2c_unregister_driver(void) { } + +#endif + +static int __init ad5064_init(void) +{ +	int ret; + +	ret = ad5064_spi_register_driver(); +	if (ret) +		return ret; + +	ret = ad5064_i2c_register_driver(); +	if (ret) { +		ad5064_spi_unregister_driver(); +		return ret; +	} + +	return 0; +} +module_init(ad5064_init); + +static void __exit ad5064_exit(void) +{ +	ad5064_i2c_unregister_driver(); +	ad5064_spi_unregister_driver(); +} +module_exit(ad5064_exit); + +MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); +MODULE_DESCRIPTION("Analog Devices AD5024 and similar multi-channel DACs"); +MODULE_LICENSE("GPL v2");  | 
