diff options
Diffstat (limited to 'drivers/staging/iio/dac/ad5504.c')
| -rw-r--r-- | drivers/staging/iio/dac/ad5504.c | 404 |
1 files changed, 404 insertions, 0 deletions
diff --git a/drivers/staging/iio/dac/ad5504.c b/drivers/staging/iio/dac/ad5504.c new file mode 100644 index 000000000000..ed029cdff300 --- /dev/null +++ b/drivers/staging/iio/dac/ad5504.c @@ -0,0 +1,404 @@ +/* + * AD5504, AD5501 High Voltage Digital to Analog Converter + * + * Copyright 2011 Analog Devices Inc. + * + * Licensed under the GPL-2. + */ + +#include <linux/interrupt.h> +#include <linux/gpio.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 "../iio.h" +#include "../sysfs.h" +#include "dac.h" +#include "ad5504.h" + +static int ad5504_spi_write(struct spi_device *spi, u8 addr, u16 val) +{ + u16 tmp = cpu_to_be16(AD5504_CMD_WRITE | + AD5504_ADDR(addr) | + (val & AD5504_RES_MASK)); + + return spi_write(spi, (u8 *)&tmp, 2); +} + +static int ad5504_spi_read(struct spi_device *spi, u8 addr, u16 *val) +{ + u16 tmp = cpu_to_be16(AD5504_CMD_READ | AD5504_ADDR(addr)); + int ret; + struct spi_transfer t = { + .tx_buf = &tmp, + .rx_buf = val, + .len = 2, + }; + struct spi_message m; + + spi_message_init(&m); + spi_message_add_tail(&t, &m); + ret = spi_sync(spi, &m); + + *val = be16_to_cpu(*val) & AD5504_RES_MASK; + + return ret; +} + +static ssize_t ad5504_write_dac(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct ad5504_state *st = iio_dev_get_devdata(indio_dev); + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + long readin; + int ret; + + ret = strict_strtol(buf, 10, &readin); + if (ret) + return ret; + + ret = ad5504_spi_write(st->spi, this_attr->address, readin); + return ret ? ret : len; +} + +static ssize_t ad5504_read_dac(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct ad5504_state *st = iio_dev_get_devdata(indio_dev); + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + int ret; + u16 val; + + ret = ad5504_spi_read(st->spi, this_attr->address, &val); + if (ret) + return ret; + + return sprintf(buf, "%d\n", val); +} + +static ssize_t ad5504_read_powerdown_mode(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct ad5504_state *st = iio_dev_get_devdata(indio_dev); + + const char mode[][14] = {"20kohm_to_gnd", "three_state"}; + + return sprintf(buf, "%s\n", mode[st->pwr_down_mode]); +} + +static ssize_t ad5504_write_powerdown_mode(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct ad5504_state *st = iio_dev_get_devdata(indio_dev); + int ret; + + if (sysfs_streq(buf, "20kohm_to_gnd")) + st->pwr_down_mode = AD5504_DAC_PWRDN_20K; + else if (sysfs_streq(buf, "three_state")) + st->pwr_down_mode = AD5504_DAC_PWRDN_3STATE; + else + ret = -EINVAL; + + return ret ? ret : len; +} + +static ssize_t ad5504_read_dac_powerdown(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct ad5504_state *st = iio_dev_get_devdata(indio_dev); + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + + return sprintf(buf, "%d\n", + !(st->pwr_down_mask & (1 << this_attr->address))); +} + +static ssize_t ad5504_write_dac_powerdown(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + long readin; + int ret; + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct ad5504_state *st = iio_dev_get_devdata(indio_dev); + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + + ret = strict_strtol(buf, 10, &readin); + if (ret) + return ret; + + if (readin == 0) + st->pwr_down_mask |= (1 << this_attr->address); + else if (readin == 1) + st->pwr_down_mask &= ~(1 << this_attr->address); + else + ret = -EINVAL; + + ret = ad5504_spi_write(st->spi, AD5504_ADDR_CTRL, + AD5504_DAC_PWRDWN_MODE(st->pwr_down_mode) | + AD5504_DAC_PWR(st->pwr_down_mask)); + + /* writes to the CTRL register must be followed by a NOOP */ + ad5504_spi_write(st->spi, AD5504_ADDR_NOOP, 0); + + return ret ? ret : len; +} + +static ssize_t ad5504_show_scale(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct ad5504_state *st = iio_dev_get_devdata(indio_dev); + /* Corresponds to Vref / 2^(bits) */ + unsigned int scale_uv = (st->vref_mv * 1000) >> AD5505_BITS; + + return sprintf(buf, "%d.%03d\n", scale_uv / 1000, scale_uv % 1000); +} +static IIO_DEVICE_ATTR(out_scale, S_IRUGO, ad5504_show_scale, NULL, 0); + +#define IIO_DEV_ATTR_OUT_RW_RAW(_num, _show, _store, _addr) \ + IIO_DEVICE_ATTR(out##_num##_raw, \ + S_IRUGO | S_IWUSR, _show, _store, _addr) + +static IIO_DEV_ATTR_OUT_RW_RAW(0, ad5504_read_dac, + ad5504_write_dac, AD5504_ADDR_DAC0); +static IIO_DEV_ATTR_OUT_RW_RAW(1, ad5504_read_dac, + ad5504_write_dac, AD5504_ADDR_DAC1); +static IIO_DEV_ATTR_OUT_RW_RAW(2, ad5504_read_dac, + ad5504_write_dac, AD5504_ADDR_DAC2); +static IIO_DEV_ATTR_OUT_RW_RAW(3, ad5504_read_dac, + ad5504_write_dac, AD5504_ADDR_DAC3); + +static IIO_DEVICE_ATTR(out_powerdown_mode, S_IRUGO | + S_IWUSR, ad5504_read_powerdown_mode, + ad5504_write_powerdown_mode, 0); + +static IIO_CONST_ATTR(out_powerdown_mode_available, + "20kohm_to_gnd three_state"); + +#define IIO_DEV_ATTR_DAC_POWERDOWN(_num, _show, _store, _addr) \ + IIO_DEVICE_ATTR(out##_num##_powerdown, \ + S_IRUGO | S_IWUSR, _show, _store, _addr) + +static IIO_DEV_ATTR_DAC_POWERDOWN(0, ad5504_read_dac_powerdown, + ad5504_write_dac_powerdown, 0); +static IIO_DEV_ATTR_DAC_POWERDOWN(1, ad5504_read_dac_powerdown, + ad5504_write_dac_powerdown, 1); +static IIO_DEV_ATTR_DAC_POWERDOWN(2, ad5504_read_dac_powerdown, + ad5504_write_dac_powerdown, 2); +static IIO_DEV_ATTR_DAC_POWERDOWN(3, ad5504_read_dac_powerdown, + ad5504_write_dac_powerdown, 3); + +static struct attribute *ad5504_attributes[] = { + &iio_dev_attr_out0_raw.dev_attr.attr, + &iio_dev_attr_out1_raw.dev_attr.attr, + &iio_dev_attr_out2_raw.dev_attr.attr, + &iio_dev_attr_out3_raw.dev_attr.attr, + &iio_dev_attr_out0_powerdown.dev_attr.attr, + &iio_dev_attr_out1_powerdown.dev_attr.attr, + &iio_dev_attr_out2_powerdown.dev_attr.attr, + &iio_dev_attr_out3_powerdown.dev_attr.attr, + &iio_dev_attr_out_powerdown_mode.dev_attr.attr, + &iio_const_attr_out_powerdown_mode_available.dev_attr.attr, + &iio_dev_attr_out_scale.dev_attr.attr, + NULL, +}; + +static const struct attribute_group ad5504_attribute_group = { + .attrs = ad5504_attributes, +}; + +static struct attribute *ad5501_attributes[] = { + &iio_dev_attr_out0_raw.dev_attr.attr, + &iio_dev_attr_out0_powerdown.dev_attr.attr, + &iio_dev_attr_out_powerdown_mode.dev_attr.attr, + &iio_const_attr_out_powerdown_mode_available.dev_attr.attr, + &iio_dev_attr_out_scale.dev_attr.attr, + NULL, +}; + +static const struct attribute_group ad5501_attribute_group = { + .attrs = ad5501_attributes, +}; + +static IIO_CONST_ATTR(temp0_thresh_rising_value, "110000"); +static IIO_CONST_ATTR(temp0_thresh_rising_en, "1"); + +static struct attribute *ad5504_ev_attributes[] = { + &iio_const_attr_temp0_thresh_rising_value.dev_attr.attr, + &iio_const_attr_temp0_thresh_rising_en.dev_attr.attr, + NULL, +}; + +static struct attribute_group ad5504_ev_attribute_group = { + .attrs = ad5504_ev_attributes, +}; + +static irqreturn_t ad5504_event_handler(int irq, void *private) +{ + iio_push_event(private, 0, + IIO_UNMOD_EVENT_CODE(IIO_EV_CLASS_TEMP, + 0, + IIO_EV_TYPE_THRESH, + IIO_EV_DIR_RISING), + iio_get_time_ns()); + + return IRQ_HANDLED; +} + +static const struct iio_info ad5504_info = { + .attrs = &ad5504_attribute_group, + .num_interrupt_lines = 1, + .event_attrs = &ad5504_ev_attribute_group, + .driver_module = THIS_MODULE, +}; + +static const struct iio_info ad5501_info = { + .attrs = &ad5501_attribute_group, + .num_interrupt_lines = 1, + .event_attrs = &ad5504_ev_attribute_group, + .driver_module = THIS_MODULE, +}; + +static int __devinit ad5504_probe(struct spi_device *spi) +{ + struct ad5504_platform_data *pdata = spi->dev.platform_data; + struct ad5504_state *st; + int ret, voltage_uv = 0; + + st = kzalloc(sizeof(*st), GFP_KERNEL); + if (st == NULL) { + ret = -ENOMEM; + goto error_ret; + } + + spi_set_drvdata(spi, st); + + st->reg = regulator_get(&spi->dev, "vcc"); + if (!IS_ERR(st->reg)) { + ret = regulator_enable(st->reg); + if (ret) + goto error_put_reg; + + voltage_uv = regulator_get_voltage(st->reg); + } + + if (voltage_uv) + st->vref_mv = voltage_uv / 1000; + else if (pdata) + st->vref_mv = pdata->vref_mv; + else + dev_warn(&spi->dev, "reference voltage unspecified\n"); + + st->spi = spi; + st->indio_dev = iio_allocate_device(0); + if (st->indio_dev == NULL) { + ret = -ENOMEM; + goto error_disable_reg; + } + st->indio_dev->dev.parent = &spi->dev; + st->indio_dev->name = spi_get_device_id(st->spi)->name; + if (spi_get_device_id(st->spi)->driver_data == ID_AD5501) + st->indio_dev->info = &ad5501_info; + else + st->indio_dev->info = &ad5504_info; + st->indio_dev->dev_data = (void *)(st); + st->indio_dev->modes = INDIO_DIRECT_MODE; + + ret = iio_device_register(st->indio_dev); + if (ret) + goto error_free_dev; + + if (spi->irq) { + ret = request_threaded_irq(spi->irq, + NULL, + &ad5504_event_handler, + IRQF_TRIGGER_FALLING | IRQF_ONESHOT, + spi_get_device_id(st->spi)->name, + st->indio_dev); + if (ret) + goto error_unreg_iio_device; + } + + return 0; + +error_unreg_iio_device: + iio_device_unregister(st->indio_dev); +error_free_dev: + iio_free_device(st->indio_dev); +error_disable_reg: + if (!IS_ERR(st->reg)) + regulator_disable(st->reg); +error_put_reg: + if (!IS_ERR(st->reg)) + regulator_put(st->reg); + + kfree(st); +error_ret: + return ret; +} + +static int __devexit ad5504_remove(struct spi_device *spi) +{ + struct ad5504_state *st = spi_get_drvdata(spi); + + if (spi->irq) + free_irq(spi->irq, st->indio_dev); + + iio_device_unregister(st->indio_dev); + + if (!IS_ERR(st->reg)) { + regulator_disable(st->reg); + regulator_put(st->reg); + } + + kfree(st); + + return 0; +} + +static const struct spi_device_id ad5504_id[] = { + {"ad5504", ID_AD5504}, + {"ad5501", ID_AD5501}, + {} +}; + +static struct spi_driver ad5504_driver = { + .driver = { + .name = "ad5504", + .owner = THIS_MODULE, + }, + .probe = ad5504_probe, + .remove = __devexit_p(ad5504_remove), + .id_table = ad5504_id, +}; + +static __init int ad5504_spi_init(void) +{ + return spi_register_driver(&ad5504_driver); +} +module_init(ad5504_spi_init); + +static __exit void ad5504_spi_exit(void) +{ + spi_unregister_driver(&ad5504_driver); +} +module_exit(ad5504_spi_exit); + +MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); +MODULE_DESCRIPTION("Analog Devices AD5501/AD5501 DAC"); +MODULE_LICENSE("GPL v2"); |