diff options
Diffstat (limited to 'kernel/drivers/iio/dac/ad5064.c')
| -rw-r--r-- | kernel/drivers/iio/dac/ad5064.c | 684 |
1 files changed, 684 insertions, 0 deletions
diff --git a/kernel/drivers/iio/dac/ad5064.c b/kernel/drivers/iio/dac/ad5064.c new file mode 100644 index 000000000..f03b92fd3 --- /dev/null +++ b/kernel/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"); |