X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=kernel%2Fdrivers%2Fiio%2Fdac%2Fad5686.c;fp=kernel%2Fdrivers%2Fiio%2Fdac%2Fad5686.c;h=15c73e20272d874655e544366e2a8d6f1c24912a;hb=9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00;hp=0000000000000000000000000000000000000000;hpb=98260f3884f4a202f9ca5eabed40b1354c489b29;p=kvmfornfv.git diff --git a/kernel/drivers/iio/dac/ad5686.c b/kernel/drivers/iio/dac/ad5686.c new file mode 100644 index 000000000..15c73e202 --- /dev/null +++ b/kernel/drivers/iio/dac/ad5686.c @@ -0,0 +1,408 @@ +/* + * AD5686R, AD5685R, AD5684R Digital to analog converters driver + * + * Copyright 2011 Analog Devices Inc. + * + * Licensed under the GPL-2. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#define AD5686_DAC_CHANNELS 4 + +#define AD5686_ADDR(x) ((x) << 16) +#define AD5686_CMD(x) ((x) << 20) + +#define AD5686_ADDR_DAC(chan) (0x1 << (chan)) +#define AD5686_ADDR_ALL_DAC 0xF + +#define AD5686_CMD_NOOP 0x0 +#define AD5686_CMD_WRITE_INPUT_N 0x1 +#define AD5686_CMD_UPDATE_DAC_N 0x2 +#define AD5686_CMD_WRITE_INPUT_N_UPDATE_N 0x3 +#define AD5686_CMD_POWERDOWN_DAC 0x4 +#define AD5686_CMD_LDAC_MASK 0x5 +#define AD5686_CMD_RESET 0x6 +#define AD5686_CMD_INTERNAL_REFER_SETUP 0x7 +#define AD5686_CMD_DAISY_CHAIN_ENABLE 0x8 +#define AD5686_CMD_READBACK_ENABLE 0x9 + +#define AD5686_LDAC_PWRDN_NONE 0x0 +#define AD5686_LDAC_PWRDN_1K 0x1 +#define AD5686_LDAC_PWRDN_100K 0x2 +#define AD5686_LDAC_PWRDN_3STATE 0x3 + +/** + * struct ad5686_chip_info - chip specific information + * @int_vref_mv: AD5620/40/60: the internal reference voltage + * @channel: channel specification +*/ + +struct ad5686_chip_info { + u16 int_vref_mv; + struct iio_chan_spec channel[AD5686_DAC_CHANNELS]; +}; + +/** + * struct ad5446_state - driver instance specific data + * @spi: spi_device + * @chip_info: chip model specific constants, available modes etc + * @reg: supply regulator + * @vref_mv: actual reference voltage used + * @pwr_down_mask: power down mask + * @pwr_down_mode: current power down mode + * @data: spi transfer buffers + */ + +struct ad5686_state { + struct spi_device *spi; + const struct ad5686_chip_info *chip_info; + struct regulator *reg; + unsigned short vref_mv; + unsigned pwr_down_mask; + unsigned pwr_down_mode; + /* + * DMA (thus cache coherency maintenance) requires the + * transfer buffers to live in their own cache lines. + */ + + union { + __be32 d32; + u8 d8[4]; + } data[3] ____cacheline_aligned; +}; + +/** + * ad5686_supported_device_ids: + */ + +enum ad5686_supported_device_ids { + ID_AD5684, + ID_AD5685, + ID_AD5686, +}; +static int ad5686_spi_write(struct ad5686_state *st, + u8 cmd, u8 addr, u16 val, u8 shift) +{ + val <<= shift; + + st->data[0].d32 = cpu_to_be32(AD5686_CMD(cmd) | + AD5686_ADDR(addr) | + val); + + return spi_write(st->spi, &st->data[0].d8[1], 3); +} + +static int ad5686_spi_read(struct ad5686_state *st, u8 addr) +{ + struct spi_transfer t[] = { + { + .tx_buf = &st->data[0].d8[1], + .len = 3, + .cs_change = 1, + }, { + .tx_buf = &st->data[1].d8[1], + .rx_buf = &st->data[2].d8[1], + .len = 3, + }, + }; + int ret; + + st->data[0].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_READBACK_ENABLE) | + AD5686_ADDR(addr)); + st->data[1].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_NOOP)); + + ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t)); + if (ret < 0) + return ret; + + return be32_to_cpu(st->data[2].d32); +} + +static const char * const ad5686_powerdown_modes[] = { + "1kohm_to_gnd", + "100kohm_to_gnd", + "three_state" +}; + +static int ad5686_get_powerdown_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan) +{ + struct ad5686_state *st = iio_priv(indio_dev); + + return ((st->pwr_down_mode >> (chan->channel * 2)) & 0x3) - 1; +} + +static int ad5686_set_powerdown_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, unsigned int mode) +{ + struct ad5686_state *st = iio_priv(indio_dev); + + st->pwr_down_mode &= ~(0x3 << (chan->channel * 2)); + st->pwr_down_mode |= ((mode + 1) << (chan->channel * 2)); + + return 0; +} + +static const struct iio_enum ad5686_powerdown_mode_enum = { + .items = ad5686_powerdown_modes, + .num_items = ARRAY_SIZE(ad5686_powerdown_modes), + .get = ad5686_get_powerdown_mode, + .set = ad5686_set_powerdown_mode, +}; + +static ssize_t ad5686_read_dac_powerdown(struct iio_dev *indio_dev, + uintptr_t private, const struct iio_chan_spec *chan, char *buf) +{ + struct ad5686_state *st = iio_priv(indio_dev); + + return sprintf(buf, "%d\n", !!(st->pwr_down_mask & + (0x3 << (chan->channel * 2)))); +} + +static ssize_t ad5686_write_dac_powerdown(struct iio_dev *indio_dev, + uintptr_t private, const struct iio_chan_spec *chan, const char *buf, + size_t len) +{ + bool readin; + int ret; + struct ad5686_state *st = iio_priv(indio_dev); + + ret = strtobool(buf, &readin); + if (ret) + return ret; + + if (readin) + st->pwr_down_mask |= (0x3 << (chan->channel * 2)); + else + st->pwr_down_mask &= ~(0x3 << (chan->channel * 2)); + + ret = ad5686_spi_write(st, AD5686_CMD_POWERDOWN_DAC, 0, + st->pwr_down_mask & st->pwr_down_mode, 0); + + return ret ? ret : len; +} + +static int ad5686_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2, + long m) +{ + struct ad5686_state *st = iio_priv(indio_dev); + int ret; + + switch (m) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&indio_dev->mlock); + ret = ad5686_spi_read(st, chan->address); + mutex_unlock(&indio_dev->mlock); + if (ret < 0) + return ret; + *val = ret; + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + *val = st->vref_mv; + *val2 = chan->scan_type.realbits; + return IIO_VAL_FRACTIONAL_LOG2; + } + return -EINVAL; +} + +static int ad5686_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, + int val2, + long mask) +{ + struct ad5686_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 = ad5686_spi_write(st, + AD5686_CMD_WRITE_INPUT_N_UPDATE_N, + chan->address, + val, + chan->scan_type.shift); + mutex_unlock(&indio_dev->mlock); + break; + default: + ret = -EINVAL; + } + + return ret; +} + +static const struct iio_info ad5686_info = { + .read_raw = ad5686_read_raw, + .write_raw = ad5686_write_raw, + .driver_module = THIS_MODULE, +}; + +static const struct iio_chan_spec_ext_info ad5686_ext_info[] = { + { + .name = "powerdown", + .read = ad5686_read_dac_powerdown, + .write = ad5686_write_dac_powerdown, + .shared = IIO_SEPARATE, + }, + IIO_ENUM("powerdown_mode", IIO_SEPARATE, &ad5686_powerdown_mode_enum), + IIO_ENUM_AVAILABLE("powerdown_mode", &ad5686_powerdown_mode_enum), + { }, +}; + +#define AD5868_CHANNEL(chan, bits, _shift) { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .output = 1, \ + .channel = chan, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\ + .address = AD5686_ADDR_DAC(chan), \ + .scan_type = { \ + .sign = 'u', \ + .realbits = (bits), \ + .storagebits = 16, \ + .shift = (_shift), \ + }, \ + .ext_info = ad5686_ext_info, \ +} + +static const struct ad5686_chip_info ad5686_chip_info_tbl[] = { + [ID_AD5684] = { + .channel[0] = AD5868_CHANNEL(0, 12, 4), + .channel[1] = AD5868_CHANNEL(1, 12, 4), + .channel[2] = AD5868_CHANNEL(2, 12, 4), + .channel[3] = AD5868_CHANNEL(3, 12, 4), + .int_vref_mv = 2500, + }, + [ID_AD5685] = { + .channel[0] = AD5868_CHANNEL(0, 14, 2), + .channel[1] = AD5868_CHANNEL(1, 14, 2), + .channel[2] = AD5868_CHANNEL(2, 14, 2), + .channel[3] = AD5868_CHANNEL(3, 14, 2), + .int_vref_mv = 2500, + }, + [ID_AD5686] = { + .channel[0] = AD5868_CHANNEL(0, 16, 0), + .channel[1] = AD5868_CHANNEL(1, 16, 0), + .channel[2] = AD5868_CHANNEL(2, 16, 0), + .channel[3] = AD5868_CHANNEL(3, 16, 0), + .int_vref_mv = 2500, + }, +}; + + +static int ad5686_probe(struct spi_device *spi) +{ + struct ad5686_state *st; + struct iio_dev *indio_dev; + int ret, voltage_uv = 0; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); + if (indio_dev == NULL) + return -ENOMEM; + + st = iio_priv(indio_dev); + spi_set_drvdata(spi, indio_dev); + + st->reg = devm_regulator_get_optional(&spi->dev, "vcc"); + if (!IS_ERR(st->reg)) { + ret = regulator_enable(st->reg); + if (ret) + return ret; + + ret = regulator_get_voltage(st->reg); + if (ret < 0) + goto error_disable_reg; + + voltage_uv = ret; + } + + st->chip_info = + &ad5686_chip_info_tbl[spi_get_device_id(spi)->driver_data]; + + if (voltage_uv) + st->vref_mv = voltage_uv / 1000; + else + st->vref_mv = st->chip_info->int_vref_mv; + + st->spi = spi; + + /* Set all the power down mode for all channels to 1K pulldown */ + st->pwr_down_mode = 0x55; + + indio_dev->dev.parent = &spi->dev; + indio_dev->name = spi_get_device_id(spi)->name; + indio_dev->info = &ad5686_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = st->chip_info->channel; + indio_dev->num_channels = AD5686_DAC_CHANNELS; + + ret = ad5686_spi_write(st, AD5686_CMD_INTERNAL_REFER_SETUP, 0, + !!voltage_uv, 0); + if (ret) + goto error_disable_reg; + + ret = iio_device_register(indio_dev); + if (ret) + goto error_disable_reg; + + return 0; + +error_disable_reg: + if (!IS_ERR(st->reg)) + regulator_disable(st->reg); + return ret; +} + +static int ad5686_remove(struct spi_device *spi) +{ + struct iio_dev *indio_dev = spi_get_drvdata(spi); + struct ad5686_state *st = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + if (!IS_ERR(st->reg)) + regulator_disable(st->reg); + + return 0; +} + +static const struct spi_device_id ad5686_id[] = { + {"ad5684", ID_AD5684}, + {"ad5685", ID_AD5685}, + {"ad5686", ID_AD5686}, + {} +}; +MODULE_DEVICE_TABLE(spi, ad5686_id); + +static struct spi_driver ad5686_driver = { + .driver = { + .name = "ad5686", + .owner = THIS_MODULE, + }, + .probe = ad5686_probe, + .remove = ad5686_remove, + .id_table = ad5686_id, +}; +module_spi_driver(ad5686_driver); + +MODULE_AUTHOR("Michael Hennerich "); +MODULE_DESCRIPTION("Analog Devices AD5686/85/84 DAC"); +MODULE_LICENSE("GPL v2");