Datasheet of this chip: http://www.ti.com/lit/ds/symlink/dac7311.pdf Signed-off-by: Charles-Antoine Couret <charles-antoine.couret@xxxxxxxxxxxxx> --- drivers/iio/dac/Kconfig | 9 + drivers/iio/dac/Makefile | 1 + drivers/iio/dac/ti-dac7311.c | 361 +++++++++++++++++++++++++++++++++++ 3 files changed, 371 insertions(+) create mode 100644 drivers/iio/dac/ti-dac7311.c diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig index 80beb64e9e0c..ac205c8f5de0 100644 --- a/drivers/iio/dac/Kconfig +++ b/drivers/iio/dac/Kconfig @@ -356,6 +356,15 @@ config TI_DAC5571 If compiled as a module, it will be called ti-dac5571. +config TI_DAC7311 + tristate "Texas Instruments 8/10/12-bit 1-channel DAC driver" + depends on SPI + help + Driver for the Texas Instruments + DAC7311, DAC6311, DAC5311. + + If compiled as a module, it will be called ti-dac7311. + config VF610_DAC tristate "Vybrid vf610 DAC driver" depends on OF diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile index a1b37cf99441..4b02021cc30f 100644 --- a/drivers/iio/dac/Makefile +++ b/drivers/iio/dac/Makefile @@ -39,4 +39,5 @@ obj-$(CONFIG_STM32_DAC_CORE) += stm32-dac-core.o obj-$(CONFIG_STM32_DAC) += stm32-dac.o obj-$(CONFIG_TI_DAC082S085) += ti-dac082s085.o obj-$(CONFIG_TI_DAC5571) += ti-dac5571.o +obj-$(CONFIG_TI_DAC7311) += ti-dac7311.o obj-$(CONFIG_VF610_DAC) += vf610_dac.o diff --git a/drivers/iio/dac/ti-dac7311.c b/drivers/iio/dac/ti-dac7311.c new file mode 100644 index 000000000000..e7e61a7ce619 --- /dev/null +++ b/drivers/iio/dac/ti-dac7311.c @@ -0,0 +1,361 @@ +// SPDX-License-Identifier: GPL-2.0 +/* ti-dac7311.c - Texas Instruments 8/10/12-bit 1-channel DAC driver + * + * Copyright (C) 2018 CMC NV + * + * http://www.ti.com/lit/ds/symlink/dac7311.pdf + */ + +#include <linux/iio/iio.h> +#include <linux/module.h> +#include <linux/regulator/consumer.h> +#include <linux/spi/spi.h> + +enum { + SINGLE_8BITS = 0, + SINGLE_10BITS, + SINGLE_12BITS, +}; + +enum { + POWER_RUNNING = 0, + POWER_1KOHM_TO_GND, + POWER_100KOHM_TO_GND, + POWER_TRI_STATE, +}; + +struct ti_dac_spec { + u8 num_channels; + u8 resolution; +}; + +static const struct ti_dac_spec ti_dac_spec[] = { + [SINGLE_8BITS] = { .num_channels = 1, .resolution = 8 }, + [SINGLE_10BITS] = { .num_channels = 1, .resolution = 10 }, + [SINGLE_12BITS] = { .num_channels = 1, .resolution = 12 }, +}; + +/** + * struct ti_dac_chip - TI DAC chip + * @lock: protects write sequences + * @vref: regulator generating Vref + * @mesg: SPI message to perform a write + * @xfer: SPI transfer used by @mesg + * @val: cached value + * @powerdown: whether the chip is powered down + * @powerdown_mode: selected by the user + * @resolution: resolution of the chip + * @buf: buffer for @xfer + */ +struct ti_dac_chip { + struct mutex lock; + struct regulator *vref; + struct spi_message mesg; + struct spi_transfer xfer; + u16 val; + bool powerdown; + u8 powerdown_mode; + u8 resolution; + u8 buf[2] ____cacheline_aligned; +}; + +static int ti_dac_cmd(struct ti_dac_chip *ti_dac, u8 power, u16 val) +{ + u8 shift = 14 - ti_dac->resolution; + + ti_dac->buf[0] = (val << shift) & 0xFF; + ti_dac->buf[1] = (power << 6) | (val >> (8 - shift)); + return spi_sync(ti_dac->mesg.spi, &ti_dac->mesg); +} + +static const char * const ti_dac_powerdown_modes[] = { + "running", + "1kohm_to_gnd", + "100kohm_to_gnd", + "three_state", +}; + +static int ti_dac_get_powerdown_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan) +{ + struct ti_dac_chip *ti_dac = iio_priv(indio_dev); + + return ti_dac->powerdown_mode; +} + +static int ti_dac_set_powerdown_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + unsigned int mode) +{ + struct ti_dac_chip *ti_dac = iio_priv(indio_dev); + int ret = 0; + + if (ti_dac->powerdown_mode == mode) + return ret; + + mutex_lock(&ti_dac->lock); + if (ti_dac->powerdown) { + ret = ti_dac_cmd(ti_dac, ti_dac->powerdown_mode, ti_dac->val); + if (ret) + goto out; + } + ti_dac->powerdown_mode = mode; + +out: + mutex_unlock(&ti_dac->lock); + return ret; +} + +static const struct iio_enum ti_dac_powerdown_mode = { + .items = ti_dac_powerdown_modes, + .num_items = ARRAY_SIZE(ti_dac_powerdown_modes), + .get = ti_dac_get_powerdown_mode, + .set = ti_dac_set_powerdown_mode, +}; + +static ssize_t ti_dac_read_powerdown(struct iio_dev *indio_dev, + uintptr_t private, + const struct iio_chan_spec *chan, + char *buf) +{ + struct ti_dac_chip *ti_dac = iio_priv(indio_dev); + + return sprintf(buf, "%d\n", ti_dac->powerdown); +} + +static ssize_t ti_dac_write_powerdown(struct iio_dev *indio_dev, + uintptr_t private, + const struct iio_chan_spec *chan, + const char *buf, size_t len) +{ + struct ti_dac_chip *ti_dac = iio_priv(indio_dev); + bool powerdown; + int ret; + + ret = strtobool(buf, &powerdown); + if (ret) + return ret; + + if (ti_dac->powerdown == powerdown) + return len; + + mutex_lock(&ti_dac->lock); + ret = ti_dac_cmd(ti_dac, ti_dac->powerdown_mode, 0); + if (!ret) + ti_dac->powerdown = powerdown; + mutex_unlock(&ti_dac->lock); + + return ret ? ret : len; +} + +static const struct iio_chan_spec_ext_info ti_dac_ext_info[] = { + { + .name = "powerdown", + .read = ti_dac_read_powerdown, + .write = ti_dac_write_powerdown, + .shared = IIO_SHARED_BY_TYPE, + }, + IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE, &ti_dac_powerdown_mode), + IIO_ENUM_AVAILABLE("powerdown_mode", &ti_dac_powerdown_mode), + { }, +}; + +#define TI_DAC_CHANNEL(chan) { \ + .type = IIO_VOLTAGE, \ + .channel = (chan), \ + .address = (chan), \ + .output = true, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ + .ext_info = ti_dac_ext_info, \ +} + +static const struct iio_chan_spec ti_dac_channels[] = { + TI_DAC_CHANNEL(0), +}; + +static int ti_dac_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct ti_dac_chip *ti_dac = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + *val = ti_dac->val; + ret = IIO_VAL_INT; + break; + + case IIO_CHAN_INFO_SCALE: + ret = regulator_get_voltage(ti_dac->vref); + if (ret < 0) + return ret; + + *val = ret / 1000; + *val2 = ti_dac->resolution; + ret = IIO_VAL_FRACTIONAL_LOG2; + break; + + default: + ret = -EINVAL; + } + + return ret; +} + +static int ti_dac_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct ti_dac_chip *ti_dac = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + if (ti_dac->val == val) + return 0; + + if (val >= (1 << ti_dac->resolution) || val < 0) + return -EINVAL; + + if (ti_dac->powerdown) + return -EBUSY; + + mutex_lock(&ti_dac->lock); + ret = ti_dac_cmd(ti_dac, ti_dac->powerdown_mode, val); + if (!ret) + ti_dac->val = val; + mutex_unlock(&ti_dac->lock); + break; + + default: + ret = -EINVAL; + } + + return ret; +} + +static int ti_dac_write_raw_get_fmt(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, long mask) +{ + return IIO_VAL_INT; +} + +static const struct iio_info ti_dac_info = { + .read_raw = ti_dac_read_raw, + .write_raw = ti_dac_write_raw, + .write_raw_get_fmt = ti_dac_write_raw_get_fmt, +}; + +static int ti_dac_probe(struct spi_device *spi) +{ + struct device *dev = &spi->dev; + const struct ti_dac_spec *spec; + struct ti_dac_chip *ti_dac; + struct iio_dev *indio_dev; + int ret; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*ti_dac)); + if (!indio_dev) { + dev_err(dev, "can not allocate iio device\n"); + return -ENOMEM; + } + + spi->max_speed_hz = 50000000; + spi->mode = SPI_MODE_1; + spi->irq = -1; + spi->bits_per_word = 16; + spi_setup(spi); + + indio_dev->dev.parent = dev; + indio_dev->dev.of_node = spi->dev.of_node; + indio_dev->info = &ti_dac_info; + indio_dev->name = spi_get_device_id(spi)->name; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = ti_dac_channels; + spi_set_drvdata(spi, indio_dev); + + ti_dac = iio_priv(indio_dev); + ti_dac->powerdown_mode = POWER_RUNNING; + ti_dac->val = 0; + ti_dac->xfer.tx_buf = &ti_dac->buf; + ti_dac->xfer.len = sizeof(ti_dac->buf); + spi_message_init_with_transfers(&ti_dac->mesg, &ti_dac->xfer, 1); + ti_dac->mesg.spi = spi; + + spec = &ti_dac_spec[spi_get_device_id(spi)->driver_data]; + indio_dev->num_channels = spec->num_channels; + ti_dac->resolution = spec->resolution; + + ti_dac->vref = devm_regulator_get(dev, "vref"); + if (IS_ERR(ti_dac->vref)) { + dev_err(dev, "error to get regulator\n"); + return PTR_ERR(ti_dac->vref); + } + + ret = regulator_enable(ti_dac->vref); + if (ret < 0) { + dev_err(dev, "can not enable regulator\n"); + return ret; + } + + mutex_init(&ti_dac->lock); + + ret = iio_device_register(indio_dev); + if (ret) { + dev_err(dev, "fail to register iio device: %d\n", ret); + goto err; + } + + return 0; + +err: + mutex_destroy(&ti_dac->lock); + regulator_disable(ti_dac->vref); + return ret; +} + +static int ti_dac_remove(struct spi_device *spi) +{ + struct iio_dev *indio_dev = spi_get_drvdata(spi); + struct ti_dac_chip *ti_dac = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + mutex_destroy(&ti_dac->lock); + regulator_disable(ti_dac->vref); + return 0; +} + +#ifdef CONFIG_OF +static const struct of_device_id ti_dac_of_id[] = { + { .compatible = "ti,dac5311" }, + { .compatible = "ti,dac6311" }, + { .compatible = "ti,dac7311" }, + { } +}; +MODULE_DEVICE_TABLE(of, ti_dac_of_id); +#endif + +static const struct spi_device_id ti_dac_spi_id[] = { + { "dac5311", SINGLE_8BITS }, + { "dac6311", SINGLE_10BITS }, + { "dac7311", SINGLE_12BITS }, + { } +}; +MODULE_DEVICE_TABLE(spi, ti_dac_spi_id); + +static struct spi_driver ti_dac_driver = { + .driver = { + .name = "ti-dac7311", + .of_match_table = of_match_ptr(ti_dac_of_id), + }, + .probe = ti_dac_probe, + .remove = ti_dac_remove, + .id_table = ti_dac_spi_id, +}; +module_spi_driver(ti_dac_driver); + +MODULE_AUTHOR("Charles-Antoine Couret <charles-antoine.couret@xxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("Texas Instruments 8/10/12-bit 1-channel DAC driver"); +MODULE_LICENSE("GPL v2"); -- 2.17.1
