diff options
Diffstat (limited to 'drivers/iio/dac/ti-dac5571.c')
| -rw-r--r-- | drivers/iio/dac/ti-dac5571.c | 439 |
1 files changed, 439 insertions, 0 deletions
diff --git a/drivers/iio/dac/ti-dac5571.c b/drivers/iio/dac/ti-dac5571.c new file mode 100644 index 000000000000..dd21eebed6a8 --- /dev/null +++ b/drivers/iio/dac/ti-dac5571.c @@ -0,0 +1,439 @@ +/* + * ti-dac5571.c - Texas Instruments 8/10/12-bit 1/4-channel DAC driver + * + * Copyright (C) 2018 Prevas A/S + * + * http://www.ti.com/lit/ds/symlink/dac5571.pdf + * http://www.ti.com/lit/ds/symlink/dac6571.pdf + * http://www.ti.com/lit/ds/symlink/dac7571.pdf + * http://www.ti.com/lit/ds/symlink/dac5574.pdf + * http://www.ti.com/lit/ds/symlink/dac6574.pdf + * http://www.ti.com/lit/ds/symlink/dac7574.pdf + * http://www.ti.com/lit/ds/symlink/dac5573.pdf + * http://www.ti.com/lit/ds/symlink/dac6573.pdf + * http://www.ti.com/lit/ds/symlink/dac7573.pdf + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License (version 2) as + * published by the Free Software Foundation. + */ + +#include <linux/iio/iio.h> +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/of.h> +#include <linux/regulator/consumer.h> + +enum chip_id { + single_8bit, single_10bit, single_12bit, + quad_8bit, quad_10bit, quad_12bit +}; + +struct dac5571_spec { + u8 num_channels; + u8 resolution; +}; + +static const struct dac5571_spec dac5571_spec[] = { + [single_8bit] = {.num_channels = 1, .resolution = 8}, + [single_10bit] = {.num_channels = 1, .resolution = 10}, + [single_12bit] = {.num_channels = 1, .resolution = 12}, + [quad_8bit] = {.num_channels = 4, .resolution = 8}, + [quad_10bit] = {.num_channels = 4, .resolution = 10}, + [quad_12bit] = {.num_channels = 4, .resolution = 12}, +}; + +struct dac5571_data { + struct i2c_client *client; + int id; + struct mutex lock; + struct regulator *vref; + u16 val[4]; + bool powerdown; + u8 powerdown_mode; + struct dac5571_spec const *spec; + int (*dac5571_cmd)(struct dac5571_data *data, int channel, u16 val); + int (*dac5571_pwrdwn)(struct dac5571_data *data, int channel, u8 pwrdwn); + u8 buf[3] ____cacheline_aligned; +}; + +#define DAC5571_POWERDOWN(mode) ((mode) + 1) +#define DAC5571_POWERDOWN_FLAG BIT(0) +#define DAC5571_CHANNEL_SELECT 1 +#define DAC5571_LOADMODE_DIRECT BIT(4) +#define DAC5571_SINGLE_PWRDWN_BITS 4 +#define DAC5571_QUAD_PWRDWN_BITS 6 + +static int dac5571_cmd_single(struct dac5571_data *data, int channel, u16 val) +{ + unsigned int shift; + + shift = 12 - data->spec->resolution; + data->buf[1] = val << shift; + data->buf[0] = val >> (8 - shift); + + if (i2c_master_send(data->client, data->buf, 2) != 2) + return -EIO; + + return 0; +} + +static int dac5571_cmd_quad(struct dac5571_data *data, int channel, u16 val) +{ + unsigned int shift; + + shift = 16 - data->spec->resolution; + data->buf[2] = val << shift; + data->buf[1] = (val >> (8 - shift)); + data->buf[0] = (channel << DAC5571_CHANNEL_SELECT) | + DAC5571_LOADMODE_DIRECT; + + if (i2c_master_send(data->client, data->buf, 3) != 3) + return -EIO; + + return 0; +} + +static int dac5571_pwrdwn_single(struct dac5571_data *data, int channel, u8 pwrdwn) +{ + unsigned int shift; + + shift = 12 - data->spec->resolution; + data->buf[1] = 0; + data->buf[0] = pwrdwn << DAC5571_SINGLE_PWRDWN_BITS; + + if (i2c_master_send(data->client, data->buf, 2) != 2) + return -EIO; + + return 0; +} + +static int dac5571_pwrdwn_quad(struct dac5571_data *data, int channel, u8 pwrdwn) +{ + unsigned int shift; + + shift = 16 - data->spec->resolution; + data->buf[2] = 0; + data->buf[1] = pwrdwn << DAC5571_QUAD_PWRDWN_BITS; + data->buf[0] = (channel << DAC5571_CHANNEL_SELECT) | + DAC5571_LOADMODE_DIRECT | DAC5571_POWERDOWN_FLAG; + + if (i2c_master_send(data->client, data->buf, 3) != 3) + return -EIO; + + return 0; +} + +static const char *const dac5571_powerdown_modes[] = { + "1kohm_to_gnd", "100kohm_to_gnd", "three_state", +}; + +static int dac5571_get_powerdown_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan) +{ + struct dac5571_data *data = iio_priv(indio_dev); + + return data->powerdown_mode; +} + +static int dac5571_set_powerdown_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + unsigned int mode) +{ + struct dac5571_data *data = iio_priv(indio_dev); + int ret = 0; + + if (data->powerdown_mode == mode) + return 0; + + mutex_lock(&data->lock); + if (data->powerdown) { + ret = data->dac5571_pwrdwn(data, chan->channel, + DAC5571_POWERDOWN(mode)); + if (ret) + goto out; + } + data->powerdown_mode = mode; + + out: + mutex_unlock(&data->lock); + + return ret; +} + +static const struct iio_enum dac5571_powerdown_mode = { + .items = dac5571_powerdown_modes, + .num_items = ARRAY_SIZE(dac5571_powerdown_modes), + .get = dac5571_get_powerdown_mode, + .set = dac5571_set_powerdown_mode, +}; + +static ssize_t dac5571_read_powerdown(struct iio_dev *indio_dev, + uintptr_t private, + const struct iio_chan_spec *chan, + char *buf) +{ + struct dac5571_data *data = iio_priv(indio_dev); + + return sprintf(buf, "%d\n", data->powerdown); +} + +static ssize_t dac5571_write_powerdown(struct iio_dev *indio_dev, + uintptr_t private, + const struct iio_chan_spec *chan, + const char *buf, size_t len) +{ + struct dac5571_data *data = iio_priv(indio_dev); + bool powerdown; + int ret; + + ret = strtobool(buf, &powerdown); + if (ret) + return ret; + + if (data->powerdown == powerdown) + return len; + + mutex_lock(&data->lock); + if (powerdown) + ret = data->dac5571_pwrdwn(data, chan->channel, + DAC5571_POWERDOWN(data->powerdown_mode)); + else + ret = data->dac5571_cmd(data, chan->channel, data->val[0]); + if (ret) + goto out; + + data->powerdown = powerdown; + + out: + mutex_unlock(&data->lock); + + return ret ? ret : len; +} + + +static const struct iio_chan_spec_ext_info dac5571_ext_info[] = { + { + .name = "powerdown", + .read = dac5571_read_powerdown, + .write = dac5571_write_powerdown, + .shared = IIO_SHARED_BY_TYPE, + }, + IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE, &dac5571_powerdown_mode), + IIO_ENUM_AVAILABLE("powerdown_mode", &dac5571_powerdown_mode), + {}, +}; + +#define dac5571_CHANNEL(chan, name) { \ + .type = IIO_VOLTAGE, \ + .channel = (chan), \ + .address = (chan), \ + .indexed = true, \ + .output = true, \ + .datasheet_name = name, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ + .ext_info = dac5571_ext_info, \ +} + +static const struct iio_chan_spec dac5571_channels[] = { + dac5571_CHANNEL(0, "A"), + dac5571_CHANNEL(1, "B"), + dac5571_CHANNEL(2, "C"), + dac5571_CHANNEL(3, "D"), +}; + +static int dac5571_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct dac5571_data *data = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + *val = data->val[chan->channel]; + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + ret = regulator_get_voltage(data->vref); + if (ret < 0) + return ret; + + *val = ret / 1000; + *val2 = data->spec->resolution; + return IIO_VAL_FRACTIONAL_LOG2; + + default: + return -EINVAL; + } +} + +static int dac5571_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct dac5571_data *data = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + if (data->val[chan->channel] == val) + return 0; + + if (val >= (1 << data->spec->resolution) || val < 0) + return -EINVAL; + + if (data->powerdown) + return -EBUSY; + + mutex_lock(&data->lock); + ret = data->dac5571_cmd(data, chan->channel, val); + if (ret == 0) + data->val[chan->channel] = val; + mutex_unlock(&data->lock); + return ret; + + default: + return -EINVAL; + } +} + +static int dac5571_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 dac5571_info = { + .read_raw = dac5571_read_raw, + .write_raw = dac5571_write_raw, + .write_raw_get_fmt = dac5571_write_raw_get_fmt, +}; + +static int dac5571_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + const struct dac5571_spec *spec; + struct dac5571_data *data; + struct iio_dev *indio_dev; + int ret, i; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); + if (!indio_dev) + return -ENOMEM; + + data = iio_priv(indio_dev); + i2c_set_clientdata(client, indio_dev); + data->client = client; + + indio_dev->dev.parent = dev; + indio_dev->dev.of_node = client->dev.of_node; + indio_dev->info = &dac5571_info; + indio_dev->name = id->name; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = dac5571_channels; + + spec = &dac5571_spec[id->driver_data]; + indio_dev->num_channels = spec->num_channels; + data->spec = spec; + + data->vref = devm_regulator_get(dev, "vref"); + if (IS_ERR(data->vref)) + return PTR_ERR(data->vref); + + ret = regulator_enable(data->vref); + if (ret < 0) + return ret; + + mutex_init(&data->lock); + + switch (spec->num_channels) { + case 1: + data->dac5571_cmd = dac5571_cmd_single; + data->dac5571_pwrdwn = dac5571_pwrdwn_single; + break; + case 4: + data->dac5571_cmd = dac5571_cmd_quad; + data->dac5571_pwrdwn = dac5571_pwrdwn_quad; + break; + default: + goto err; + } + + for (i = 0; i < spec->num_channels; i++) { + ret = data->dac5571_cmd(data, i, 0); + if (ret) { + dev_err(dev, "failed to initialize channel %d to 0\n", i); + goto err; + } + } + + ret = iio_device_register(indio_dev); + if (ret) + goto err; + + return 0; + + err: + regulator_disable(data->vref); + return ret; +} + +static int dac5571_remove(struct i2c_client *i2c) +{ + struct iio_dev *indio_dev = i2c_get_clientdata(i2c); + struct dac5571_data *data = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + regulator_disable(data->vref); + + return 0; +} + +#ifdef CONFIG_OF +static const struct of_device_id dac5571_of_id[] = { + {.compatible = "ti,dac5571"}, + {.compatible = "ti,dac6571"}, + {.compatible = "ti,dac7571"}, + {.compatible = "ti,dac5574"}, + {.compatible = "ti,dac6574"}, + {.compatible = "ti,dac7574"}, + {.compatible = "ti,dac5573"}, + {.compatible = "ti,dac6573"}, + {.compatible = "ti,dac7573"}, + {} +}; +MODULE_DEVICE_TABLE(of, dac5571_of_id); +#endif + +static const struct i2c_device_id dac5571_id[] = { + {"dac5571", single_8bit}, + {"dac6571", single_10bit}, + {"dac7571", single_12bit}, + {"dac5574", quad_8bit}, + {"dac6574", quad_10bit}, + {"dac7574", quad_12bit}, + {"dac5573", quad_8bit}, + {"dac6573", quad_10bit}, + {"dac7573", quad_12bit}, + {} +}; +MODULE_DEVICE_TABLE(i2c, dac5571_id); + +static struct i2c_driver dac5571_driver = { + .driver = { + .name = "ti-dac5571", + }, + .probe = dac5571_probe, + .remove = dac5571_remove, + .id_table = dac5571_id, +}; +module_i2c_driver(dac5571_driver); + +MODULE_AUTHOR("Sean Nyekjaer <sean.nyekjaer@prevas.dk>"); +MODULE_DESCRIPTION("Texas Instruments 8/10/12-bit 1/4-channel DAC driver"); +MODULE_LICENSE("GPL v2"); |