diff options
author | Lars-Peter Clausen <lars@metafoo.de> | 2012-06-04 11:36:28 +0200 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-06-05 14:02:25 +0900 |
commit | dbdc025bb239ce62c9b4d28c459a98f22ce9ec0a (patch) | |
tree | 2858c04b9d18852c1a4f4ca1c60c8e00b6180470 /drivers/iio/dac/ad5791.c | |
parent | 20374d1a36df3e20cd6742ba376684e5506254a8 (diff) | |
download | op-kernel-dev-dbdc025bb239ce62c9b4d28c459a98f22ce9ec0a.zip op-kernel-dev-dbdc025bb239ce62c9b4d28c459a98f22ce9ec0a.tar.gz |
staging:iio: Move DAC drivers out of staging
The IIO DAC drivers are in a reasonably good shape. They all make use of channel
spec and non of them provides non-documented sysfs attributes. Code style should
be OK as well, both checkpatch and coccicheck only report trivial issues.
So lets move the whole folder out of staging.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/iio/dac/ad5791.c')
-rw-r--r-- | drivers/iio/dac/ad5791.c | 485 |
1 files changed, 485 insertions, 0 deletions
diff --git a/drivers/iio/dac/ad5791.c b/drivers/iio/dac/ad5791.c new file mode 100644 index 0000000..2bd2e37 --- /dev/null +++ b/drivers/iio/dac/ad5791.c @@ -0,0 +1,485 @@ +/* + * AD5760, AD5780, AD5781, AD5790, AD5791 Voltage Output Digital to Analog + * Converter + * + * Copyright 2011 Analog Devices Inc. + * + * Licensed under the GPL-2. + */ + +#include <linux/interrupt.h> +#include <linux/fs.h> +#include <linux/device.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/module.h> + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/dac/ad5791.h> + +#define AD5791_RES_MASK(x) ((1 << (x)) - 1) +#define AD5791_DAC_MASK AD5791_RES_MASK(20) +#define AD5791_DAC_MSB (1 << 19) + +#define AD5791_CMD_READ (1 << 23) +#define AD5791_CMD_WRITE (0 << 23) +#define AD5791_ADDR(addr) ((addr) << 20) + +/* Registers */ +#define AD5791_ADDR_NOOP 0 +#define AD5791_ADDR_DAC0 1 +#define AD5791_ADDR_CTRL 2 +#define AD5791_ADDR_CLRCODE 3 +#define AD5791_ADDR_SW_CTRL 4 + +/* Control Register */ +#define AD5791_CTRL_RBUF (1 << 1) +#define AD5791_CTRL_OPGND (1 << 2) +#define AD5791_CTRL_DACTRI (1 << 3) +#define AD5791_CTRL_BIN2SC (1 << 4) +#define AD5791_CTRL_SDODIS (1 << 5) +#define AD5761_CTRL_LINCOMP(x) ((x) << 6) + +#define AD5791_LINCOMP_0_10 0 +#define AD5791_LINCOMP_10_12 1 +#define AD5791_LINCOMP_12_16 2 +#define AD5791_LINCOMP_16_19 3 +#define AD5791_LINCOMP_19_20 12 + +#define AD5780_LINCOMP_0_10 0 +#define AD5780_LINCOMP_10_20 12 + +/* Software Control Register */ +#define AD5791_SWCTRL_LDAC (1 << 0) +#define AD5791_SWCTRL_CLR (1 << 1) +#define AD5791_SWCTRL_RESET (1 << 2) + +#define AD5791_DAC_PWRDN_6K 0 +#define AD5791_DAC_PWRDN_3STATE 1 + +/** + * struct ad5791_chip_info - chip specific information + * @get_lin_comp: function pointer to the device specific function + */ + +struct ad5791_chip_info { + int (*get_lin_comp) (unsigned int span); +}; + +/** + * struct ad5791_state - driver instance specific data + * @us: spi_device + * @reg_vdd: positive supply regulator + * @reg_vss: negative supply regulator + * @chip_info: chip model specific constants + * @vref_mv: actual reference voltage used + * @vref_neg_mv: voltage of the negative supply + * @pwr_down_mode current power down mode + */ + +struct ad5791_state { + struct spi_device *spi; + struct regulator *reg_vdd; + struct regulator *reg_vss; + const struct ad5791_chip_info *chip_info; + unsigned short vref_mv; + unsigned int vref_neg_mv; + unsigned ctrl; + unsigned pwr_down_mode; + bool pwr_down; +}; + +/** + * ad5791_supported_device_ids: + */ + +enum ad5791_supported_device_ids { + ID_AD5760, + ID_AD5780, + ID_AD5781, + ID_AD5791, +}; + +static int ad5791_spi_write(struct spi_device *spi, u8 addr, u32 val) +{ + union { + u32 d32; + u8 d8[4]; + } data; + + data.d32 = cpu_to_be32(AD5791_CMD_WRITE | + AD5791_ADDR(addr) | + (val & AD5791_DAC_MASK)); + + return spi_write(spi, &data.d8[1], 3); +} + +static int ad5791_spi_read(struct spi_device *spi, u8 addr, u32 *val) +{ + union { + u32 d32; + u8 d8[4]; + } data[3]; + int ret; + struct spi_message msg; + struct spi_transfer xfers[] = { + { + .tx_buf = &data[0].d8[1], + .bits_per_word = 8, + .len = 3, + .cs_change = 1, + }, { + .tx_buf = &data[1].d8[1], + .rx_buf = &data[2].d8[1], + .bits_per_word = 8, + .len = 3, + }, + }; + + data[0].d32 = cpu_to_be32(AD5791_CMD_READ | + AD5791_ADDR(addr)); + data[1].d32 = cpu_to_be32(AD5791_ADDR(AD5791_ADDR_NOOP)); + + spi_message_init(&msg); + spi_message_add_tail(&xfers[0], &msg); + spi_message_add_tail(&xfers[1], &msg); + ret = spi_sync(spi, &msg); + + *val = be32_to_cpu(data[2].d32); + + return ret; +} + +static const char * const ad5791_powerdown_modes[] = { + "6kohm_to_gnd", + "three_state", +}; + +static int ad5791_get_powerdown_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan) +{ + struct ad5791_state *st = iio_priv(indio_dev); + + return st->pwr_down_mode; +} + +static int ad5791_set_powerdown_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, unsigned int mode) +{ + struct ad5791_state *st = iio_priv(indio_dev); + + st->pwr_down_mode = mode; + + return 0; +} + +static const struct iio_enum ad5791_powerdown_mode_enum = { + .items = ad5791_powerdown_modes, + .num_items = ARRAY_SIZE(ad5791_powerdown_modes), + .get = ad5791_get_powerdown_mode, + .set = ad5791_set_powerdown_mode, +}; + +static ssize_t ad5791_read_dac_powerdown(struct iio_dev *indio_dev, + uintptr_t private, const struct iio_chan_spec *chan, char *buf) +{ + struct ad5791_state *st = iio_priv(indio_dev); + + return sprintf(buf, "%d\n", st->pwr_down); +} + +static ssize_t ad5791_write_dac_powerdown(struct iio_dev *indio_dev, + uintptr_t private, const struct iio_chan_spec *chan, const char *buf, + size_t len) +{ + bool pwr_down; + int ret; + struct ad5791_state *st = iio_priv(indio_dev); + + ret = strtobool(buf, &pwr_down); + if (ret) + return ret; + + if (!pwr_down) { + st->ctrl &= ~(AD5791_CTRL_OPGND | AD5791_CTRL_DACTRI); + } else { + if (st->pwr_down_mode == AD5791_DAC_PWRDN_6K) + st->ctrl |= AD5791_CTRL_OPGND; + else if (st->pwr_down_mode == AD5791_DAC_PWRDN_3STATE) + st->ctrl |= AD5791_CTRL_DACTRI; + } + st->pwr_down = pwr_down; + + ret = ad5791_spi_write(st->spi, AD5791_ADDR_CTRL, st->ctrl); + + return ret ? ret : len; +} + +static int ad5791_get_lin_comp(unsigned int span) +{ + if (span <= 10000) + return AD5791_LINCOMP_0_10; + else if (span <= 12000) + return AD5791_LINCOMP_10_12; + else if (span <= 16000) + return AD5791_LINCOMP_12_16; + else if (span <= 19000) + return AD5791_LINCOMP_16_19; + else + return AD5791_LINCOMP_19_20; +} + +static int ad5780_get_lin_comp(unsigned int span) +{ + if (span <= 10000) + return AD5780_LINCOMP_0_10; + else + return AD5780_LINCOMP_10_20; +} +static const struct ad5791_chip_info ad5791_chip_info_tbl[] = { + [ID_AD5760] = { + .get_lin_comp = ad5780_get_lin_comp, + }, + [ID_AD5780] = { + .get_lin_comp = ad5780_get_lin_comp, + }, + [ID_AD5781] = { + .get_lin_comp = ad5791_get_lin_comp, + }, + [ID_AD5791] = { + .get_lin_comp = ad5791_get_lin_comp, + }, +}; + +static int ad5791_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2, + long m) +{ + struct ad5791_state *st = iio_priv(indio_dev); + u64 val64; + int ret; + + switch (m) { + case IIO_CHAN_INFO_RAW: + ret = ad5791_spi_read(st->spi, chan->address, val); + if (ret) + return ret; + *val &= AD5791_DAC_MASK; + *val >>= chan->scan_type.shift; + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + *val = 0; + *val2 = (((u64)st->vref_mv) * 1000000ULL) >> chan->scan_type.realbits; + return IIO_VAL_INT_PLUS_MICRO; + case IIO_CHAN_INFO_OFFSET: + val64 = (((u64)st->vref_neg_mv) << chan->scan_type.realbits); + do_div(val64, st->vref_mv); + *val = -val64; + return IIO_VAL_INT; + default: + return -EINVAL; + } + +}; + +static const struct iio_chan_spec_ext_info ad5791_ext_info[] = { + { + .name = "powerdown", + .shared = true, + .read = ad5791_read_dac_powerdown, + .write = ad5791_write_dac_powerdown, + }, + IIO_ENUM("powerdown_mode", true, &ad5791_powerdown_mode_enum), + IIO_ENUM_AVAILABLE("powerdown_mode", &ad5791_powerdown_mode_enum), + { }, +}; + +#define AD5791_CHAN(bits, shift) { \ + .type = IIO_VOLTAGE, \ + .output = 1, \ + .indexed = 1, \ + .address = AD5791_ADDR_DAC0, \ + .channel = 0, \ + .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \ + IIO_CHAN_INFO_SCALE_SHARED_BIT | \ + IIO_CHAN_INFO_OFFSET_SHARED_BIT, \ + .scan_type = IIO_ST('u', bits, 24, shift), \ + .ext_info = ad5791_ext_info, \ +} + +static const struct iio_chan_spec ad5791_channels[] = { + [ID_AD5760] = AD5791_CHAN(16, 4), + [ID_AD5780] = AD5791_CHAN(18, 2), + [ID_AD5781] = AD5791_CHAN(18, 2), + [ID_AD5791] = AD5791_CHAN(20, 0) +}; + +static int ad5791_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, + int val2, + long mask) +{ + struct ad5791_state *st = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_RAW: + val &= AD5791_RES_MASK(chan->scan_type.realbits); + val <<= chan->scan_type.shift; + + return ad5791_spi_write(st->spi, chan->address, val); + + default: + return -EINVAL; + } +} + +static const struct iio_info ad5791_info = { + .read_raw = &ad5791_read_raw, + .write_raw = &ad5791_write_raw, + .driver_module = THIS_MODULE, +}; + +static int __devinit ad5791_probe(struct spi_device *spi) +{ + struct ad5791_platform_data *pdata = spi->dev.platform_data; + struct iio_dev *indio_dev; + struct ad5791_state *st; + int ret, pos_voltage_uv = 0, neg_voltage_uv = 0; + + indio_dev = iio_device_alloc(sizeof(*st)); + if (indio_dev == NULL) { + ret = -ENOMEM; + goto error_ret; + } + st = iio_priv(indio_dev); + st->reg_vdd = regulator_get(&spi->dev, "vdd"); + if (!IS_ERR(st->reg_vdd)) { + ret = regulator_enable(st->reg_vdd); + if (ret) + goto error_put_reg_pos; + + pos_voltage_uv = regulator_get_voltage(st->reg_vdd); + } + + st->reg_vss = regulator_get(&spi->dev, "vss"); + if (!IS_ERR(st->reg_vss)) { + ret = regulator_enable(st->reg_vss); + if (ret) + goto error_put_reg_neg; + + neg_voltage_uv = regulator_get_voltage(st->reg_vss); + } + + st->pwr_down = true; + st->spi = spi; + + if (!IS_ERR(st->reg_vss) && !IS_ERR(st->reg_vdd)) { + st->vref_mv = (pos_voltage_uv + neg_voltage_uv) / 1000; + st->vref_neg_mv = neg_voltage_uv / 1000; + } else if (pdata) { + st->vref_mv = pdata->vref_pos_mv + pdata->vref_neg_mv; + st->vref_neg_mv = pdata->vref_neg_mv; + } else { + dev_warn(&spi->dev, "reference voltage unspecified\n"); + } + + ret = ad5791_spi_write(spi, AD5791_ADDR_SW_CTRL, AD5791_SWCTRL_RESET); + if (ret) + goto error_disable_reg_neg; + + st->chip_info = &ad5791_chip_info_tbl[spi_get_device_id(spi) + ->driver_data]; + + + st->ctrl = AD5761_CTRL_LINCOMP(st->chip_info->get_lin_comp(st->vref_mv)) + | ((pdata && pdata->use_rbuf_gain2) ? 0 : AD5791_CTRL_RBUF) | + AD5791_CTRL_BIN2SC; + + ret = ad5791_spi_write(spi, AD5791_ADDR_CTRL, st->ctrl | + AD5791_CTRL_OPGND | AD5791_CTRL_DACTRI); + if (ret) + goto error_disable_reg_neg; + + spi_set_drvdata(spi, indio_dev); + indio_dev->dev.parent = &spi->dev; + indio_dev->info = &ad5791_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels + = &ad5791_channels[spi_get_device_id(spi)->driver_data]; + indio_dev->num_channels = 1; + indio_dev->name = spi_get_device_id(st->spi)->name; + ret = iio_device_register(indio_dev); + if (ret) + goto error_disable_reg_neg; + + return 0; + +error_disable_reg_neg: + if (!IS_ERR(st->reg_vss)) + regulator_disable(st->reg_vss); +error_put_reg_neg: + if (!IS_ERR(st->reg_vss)) + regulator_put(st->reg_vss); + + if (!IS_ERR(st->reg_vdd)) + regulator_disable(st->reg_vdd); +error_put_reg_pos: + if (!IS_ERR(st->reg_vdd)) + regulator_put(st->reg_vdd); + iio_device_free(indio_dev); +error_ret: + + return ret; +} + +static int __devexit ad5791_remove(struct spi_device *spi) +{ + struct iio_dev *indio_dev = spi_get_drvdata(spi); + struct ad5791_state *st = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + if (!IS_ERR(st->reg_vdd)) { + regulator_disable(st->reg_vdd); + regulator_put(st->reg_vdd); + } + + if (!IS_ERR(st->reg_vss)) { + regulator_disable(st->reg_vss); + regulator_put(st->reg_vss); + } + iio_device_free(indio_dev); + + return 0; +} + +static const struct spi_device_id ad5791_id[] = { + {"ad5760", ID_AD5760}, + {"ad5780", ID_AD5780}, + {"ad5781", ID_AD5781}, + {"ad5790", ID_AD5791}, + {"ad5791", ID_AD5791}, + {} +}; +MODULE_DEVICE_TABLE(spi, ad5791_id); + +static struct spi_driver ad5791_driver = { + .driver = { + .name = "ad5791", + .owner = THIS_MODULE, + }, + .probe = ad5791_probe, + .remove = __devexit_p(ad5791_remove), + .id_table = ad5791_id, +}; +module_spi_driver(ad5791_driver); + +MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); +MODULE_DESCRIPTION("Analog Devices AD5760/AD5780/AD5781/AD5790/AD5791 DAC"); +MODULE_LICENSE("GPL v2"); |