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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-09-14 11:38:48 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-09-14 11:38:48 +0300
commit4b55dce8b0e5f1440aea1b43d55e0bd4c0476737 (patch)
treeded38f68b6ba46c836d57d1f644ed52ca4e5b2dc /drivers/iio/dac/ltc1660.c
parent064ee3c0da805b57d9a8dd55eff79887a8f78532 (diff)
parentdaae7861a696b66acb3547c1cb9247cb3abaf0b3 (diff)
downloadlinux-4b55dce8b0e5f1440aea1b43d55e0bd4c0476737.tar.xz
Merge tag 'iio-for-4.20a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next
Jonathan writes: 1st round of IIO new device support, features and cleanups in the 4.20 cycle. There is a merge commit in here to pull in regmap support for repeatedly reading the same register (to read out FIFOs). Used by the adxl372 driver. This will find uses elsewhere once we tidy up various drivers that are effectively doing this and relying on not enabling regcache. New device support * Analog devices ADXL372 accelerometer - new driver for this accelerometer including fifo and and interrupt support. Follow up patches enforce trigger validation, add sampling frequency control and filter bandwidth control. A later series added i2c support to the existing SPI support. * ST lsm6dsx - rework and add support fo the LSM6DSO 6 axis mems sensor. * Linear LTC 1660 DAC - new driver supporting the LTC 1660 and LTC 1665 SPI DACs. * Microchip mcp3911 ADC. - new driver for this integrated analog front end and ADC. * Qualcomm SPMI PMIC5 adc driver - using the spmi framework, new driver and bindings for this ADC. Follow up patch adds some missing channels. Features * ad5758 - support hard reset using a gpio (if provided). * mpu6050 - Regulator support * qcom-spmi-adc5 - Sanity check the channel numbers provided by DT to make sure the driver actually knows about them. * sc27xx - give raw data for channel 20 as it's used on all known boards for the headset which needs a custom converstion function. If it turns out someone builds a board where this isn't true we will deal with it when it happens. - add ADC scale calibration. * tsl2772 - support device tree binding to set the proximity led settings. - regulator supprot. - binding for apds9930 - trivial addition as register compatible with tsl2772. Cleanups / Minor fixes * adxl345 - supress a static checker warning but explicitly checking if the id object is null. * bh1750 - avoid CONFIG_PM_SLEEP checks. - SPDX. * bme680 - spelling mistake - use clamp rather than open coding. - white space and other similar fixes. - rename MSK to MASK for clarifty and use GENMASK to specify them. - use the FIELD_GET macro rather than a very odd accessor of dividing by 16 to get the shift. - rework to share handing for oversampling of the various channels in a unified way. - check explicitly for val2 in write_raw function to ensure it is 0. - drop some field defines that don't add anything. * dpot-adc - SPDX * envelope detector - SPDX * isl29501 - fix an ancient compiler warning mostly because it results in much nicer code. * max30102 - mark switch fall throughs. * max44000 - drop an unused variable. * max512 - avoid CONFIG_PM_SLEEP checks. * max5481 - use of_device_get_match_data rather than open coding it. * max5821 - avoid CONFIG_PM_SLEEP checks. * max9611 - explicity cast an enum to an integer to make it totally clear that this is intended. * mcp4018 - fix an inconsistent MODULE_LICENSE. - use of_device_get_match_data rather than open coding it. * mcp4531 - use of_device_get_match_data rather than open coding it. - SPDX * mcp4725 - avoid CONFIG_PM_SLEEP checks. * mcp4922 - Fix error handling and prevent writing a negative to when setting the output voltage. * ms5611 - drop deprecated compatible strings without manufacturer from being explicitly listed. They are handled anyway. - SPDX * multiplexer - SPDX * qcom-vadc - fix inconsistent documentation for reg. * ti-dac5571 - provide and of_match_table. * treewide - update Michael Hennerich's email address. - Use %pOFn rather than device_node.name. * documentation. - tidy up a wrong kernel version for the introduction of the position_relative ABI.
Diffstat (limited to 'drivers/iio/dac/ltc1660.c')
-rw-r--r--drivers/iio/dac/ltc1660.c250
1 files changed, 250 insertions, 0 deletions
diff --git a/drivers/iio/dac/ltc1660.c b/drivers/iio/dac/ltc1660.c
new file mode 100644
index 000000000000..10866838c72a
--- /dev/null
+++ b/drivers/iio/dac/ltc1660.c
@@ -0,0 +1,250 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for Linear Technology LTC1665/LTC1660, 8 channels DAC
+ *
+ * Copyright (C) 2018 Marcus Folkesson <marcus.folkesson@gmail.com>
+ */
+#include <linux/bitops.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+#include <linux/regmap.h>
+#include <linux/spi/spi.h>
+
+#define LTC1660_REG_WAKE 0x0
+#define LTC1660_REG_DAC_A 0x1
+#define LTC1660_REG_DAC_B 0x2
+#define LTC1660_REG_DAC_C 0x3
+#define LTC1660_REG_DAC_D 0x4
+#define LTC1660_REG_DAC_E 0x5
+#define LTC1660_REG_DAC_F 0x6
+#define LTC1660_REG_DAC_G 0x7
+#define LTC1660_REG_DAC_H 0x8
+#define LTC1660_REG_SLEEP 0xe
+
+#define LTC1660_NUM_CHANNELS 8
+
+static const struct regmap_config ltc1660_regmap_config = {
+ .reg_bits = 4,
+ .val_bits = 12,
+};
+
+enum ltc1660_supported_device_ids {
+ ID_LTC1660,
+ ID_LTC1665,
+};
+
+struct ltc1660_priv {
+ struct spi_device *spi;
+ struct regmap *regmap;
+ struct regulator *vref_reg;
+ unsigned int value[LTC1660_NUM_CHANNELS];
+ unsigned int vref_mv;
+};
+
+static int ltc1660_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long mask)
+{
+ struct ltc1660_priv *priv = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ *val = priv->value[chan->channel];
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ *val = regulator_get_voltage(priv->vref_reg);
+ if (*val < 0) {
+ dev_err(&priv->spi->dev, "failed to read vref regulator: %d\n",
+ *val);
+ return *val;
+ }
+
+ /* Convert to mV */
+ *val /= 1000;
+ *val2 = chan->scan_type.realbits;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ltc1660_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val,
+ int val2,
+ long mask)
+{
+ struct ltc1660_priv *priv = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ if (val2 != 0)
+ return -EINVAL;
+
+ if (val < 0 || val > GENMASK(chan->scan_type.realbits - 1, 0))
+ return -EINVAL;
+
+ ret = regmap_write(priv->regmap, chan->channel,
+ (val << chan->scan_type.shift));
+ if (!ret)
+ priv->value[chan->channel] = val;
+
+ return ret;
+ default:
+ return -EINVAL;
+ }
+}
+
+#define LTC1660_CHAN(chan, bits) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .output = 1, \
+ .channel = chan, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = (bits), \
+ .storagebits = 16, \
+ .shift = 12 - (bits), \
+ }, \
+}
+
+#define LTC1660_OCTAL_CHANNELS(bits) { \
+ LTC1660_CHAN(LTC1660_REG_DAC_A, bits), \
+ LTC1660_CHAN(LTC1660_REG_DAC_B, bits), \
+ LTC1660_CHAN(LTC1660_REG_DAC_C, bits), \
+ LTC1660_CHAN(LTC1660_REG_DAC_D, bits), \
+ LTC1660_CHAN(LTC1660_REG_DAC_E, bits), \
+ LTC1660_CHAN(LTC1660_REG_DAC_F, bits), \
+ LTC1660_CHAN(LTC1660_REG_DAC_G, bits), \
+ LTC1660_CHAN(LTC1660_REG_DAC_H, bits), \
+}
+
+static const struct iio_chan_spec ltc1660_channels[][LTC1660_NUM_CHANNELS] = {
+ [ID_LTC1660] = LTC1660_OCTAL_CHANNELS(10),
+ [ID_LTC1665] = LTC1660_OCTAL_CHANNELS(8),
+};
+
+static const struct iio_info ltc1660_info = {
+ .read_raw = &ltc1660_read_raw,
+ .write_raw = &ltc1660_write_raw,
+};
+
+static int __maybe_unused ltc1660_suspend(struct device *dev)
+{
+ struct ltc1660_priv *priv = iio_priv(spi_get_drvdata(
+ to_spi_device(dev)));
+ return regmap_write(priv->regmap, LTC1660_REG_SLEEP, 0x00);
+}
+
+static int __maybe_unused ltc1660_resume(struct device *dev)
+{
+ struct ltc1660_priv *priv = iio_priv(spi_get_drvdata(
+ to_spi_device(dev)));
+ return regmap_write(priv->regmap, LTC1660_REG_WAKE, 0x00);
+}
+static SIMPLE_DEV_PM_OPS(ltc1660_pm_ops, ltc1660_suspend, ltc1660_resume);
+
+static int ltc1660_probe(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev;
+ struct ltc1660_priv *priv;
+ const struct spi_device_id *id = spi_get_device_id(spi);
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*priv));
+ if (indio_dev == NULL)
+ return -ENOMEM;
+
+ priv = iio_priv(indio_dev);
+ priv->regmap = devm_regmap_init_spi(spi, &ltc1660_regmap_config);
+ if (IS_ERR(priv->regmap)) {
+ dev_err(&spi->dev, "failed to register spi regmap %ld\n",
+ PTR_ERR(priv->regmap));
+ return PTR_ERR(priv->regmap);
+ }
+
+ priv->vref_reg = devm_regulator_get(&spi->dev, "vref");
+ if (IS_ERR(priv->vref_reg)) {
+ dev_err(&spi->dev, "vref regulator not specified\n");
+ return PTR_ERR(priv->vref_reg);
+ }
+
+ ret = regulator_enable(priv->vref_reg);
+ if (ret) {
+ dev_err(&spi->dev, "failed to enable vref regulator: %d\n",
+ ret);
+ return ret;
+ }
+
+ priv->spi = spi;
+ spi_set_drvdata(spi, indio_dev);
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->info = &ltc1660_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = ltc1660_channels[id->driver_data];
+ indio_dev->num_channels = LTC1660_NUM_CHANNELS;
+ indio_dev->name = id->name;
+
+ ret = iio_device_register(indio_dev);
+ if (ret) {
+ dev_err(&spi->dev, "failed to register iio device: %d\n",
+ ret);
+ goto error_disable_reg;
+ }
+
+ return 0;
+
+error_disable_reg:
+ regulator_disable(priv->vref_reg);
+
+ return ret;
+}
+
+static int ltc1660_remove(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev = spi_get_drvdata(spi);
+ struct ltc1660_priv *priv = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+ regulator_disable(priv->vref_reg);
+
+ return 0;
+}
+
+static const struct of_device_id ltc1660_dt_ids[] = {
+ { .compatible = "lltc,ltc1660", .data = (void *)ID_LTC1660 },
+ { .compatible = "lltc,ltc1665", .data = (void *)ID_LTC1665 },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, ltc1660_dt_ids);
+
+static const struct spi_device_id ltc1660_id[] = {
+ {"ltc1660", ID_LTC1660},
+ {"ltc1665", ID_LTC1665},
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(spi, ltc1660_id);
+
+static struct spi_driver ltc1660_driver = {
+ .driver = {
+ .name = "ltc1660",
+ .of_match_table = ltc1660_dt_ids,
+ .pm = &ltc1660_pm_ops,
+ },
+ .probe = ltc1660_probe,
+ .remove = ltc1660_remove,
+ .id_table = ltc1660_id,
+};
+module_spi_driver(ltc1660_driver);
+
+MODULE_AUTHOR("Marcus Folkesson <marcus.folkesson@gmail.com>");
+MODULE_DESCRIPTION("Linear Technology LTC1660/LTC1665 DAC");
+MODULE_LICENSE("GPL v2");