diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-07-26 11:14:49 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-07-26 11:14:49 -0700 |
commit | b13bc8dda81c54a66a1c84e66f60b8feba659f28 (patch) | |
tree | 100a26eada424fa5d9b0e5eaaf4e23b8fa036fc8 /drivers/iio/dac/ad5791.c | |
parent | 9fc377799bc9bfd8d5cb35d0d1ea2e2458cbdbb3 (diff) | |
parent | 419e9266884fa853179ab726c27a63a9d3ae46e3 (diff) |
Merge tag 'staging-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging tree patches from Greg Kroah-Hartman:
"Here's the big staging tree merge for the 3.6-rc1 merge window.
There are some patches in here outside of drivers/staging/, notibly
the iio code (which is still stradeling the staging / not staging
boundry), the pstore code, and the tracing code. All of these have
gotten acks from the various subsystem maintainers to be included in
this tree. The pstore and tracing patches are related, and are coming
here as they replace one of the android staging drivers.
Otherwise, the normal staging mess. Lots of cleanups and a few new
drivers (some iio drivers, and the large csr wireless driver
abomination.)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
Fixed up trivial conflicts in drivers/staging/comedi/drivers/s626.h and
drivers/staging/gdm72xx/netlink_k.c
* tag 'staging-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1108 commits)
staging: csr: delete a bunch of unused library functions
staging: csr: remove csr_utf16.c
staging: csr: remove csr_pmem.h
staging: csr: remove CsrPmemAlloc
staging: csr: remove CsrPmemFree()
staging: csr: remove CsrMemAllocDma()
staging: csr: remove CsrMemCalloc()
staging: csr: remove CsrMemAlloc()
staging: csr: remove CsrMemFree() and CsrMemFreeDma()
staging: csr: remove csr_util.h
staging: csr: remove CsrOffSetOf()
stating: csr: remove unneeded #includes in csr_util.c
staging: csr: make CsrUInt16ToHex static
staging: csr: remove CsrMemCpy()
staging: csr: remove CsrStrLen()
staging: csr: remove CsrVsnprintf()
staging: csr: remove CsrStrDup
staging: csr: remove CsrStrChr()
staging: csr: remove CsrStrNCmp
staging: csr: remove CsrStrCmp
...
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 00000000000..2bd2e37280f --- /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"); |