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author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-11-22 09:39:45 +0100 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-11-22 09:39:45 +0100 |
commit | 7c0bc65c84035cd2d7561ba47d7bad1cae62c4c3 (patch) | |
tree | dc3d2be87e28788beae297afecfa83a4846397b8 /drivers/iio/adc/ad7949.c | |
parent | 0e2c8fb54d7ae0c3e816dc8b1eedbeb345e9cdad (diff) | |
parent | 00426e99789357dbff7e719a092ce36a3ce49d94 (diff) | |
download | linux-stable-7c0bc65c84035cd2d7561ba47d7bad1cae62c4c3.tar.gz linux-stable-7c0bc65c84035cd2d7561ba47d7bad1cae62c4c3.tar.bz2 linux-stable-7c0bc65c84035cd2d7561ba47d7bad1cae62c4c3.zip |
Merge tag 'iio-for-4.21a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-testing
Jonathan writes:
First set of new device support, features and cleanups for IIO in the 4.21 cycle
Along with the headline feature of 5 new drivers, we have the
substantial addition of auxilliary sensor support on the lsm6sdx
parts for ST. There has also been a good set of staging cleanup
in this period with more underway.
An ever increasing number of devices supported with just a new
ID which is a good sign that at least some manufacturers are
continuing to stabilise their interfaces.
New device support,
* ad7124
- New driver supporting Analog Devices' ad7124-4 and ad7124-8 parts
with the inevitable DT binding.
* ad7949
- New driver supporting Analog Devices' ad7949, AD7682 and AD7689 ADCs.
* rm3100
- New driver supporting PNIs RM3100 magnometer with bindings and
vendor prefix.
* ti-dac7311
- New driver supporting DAC7311, DAC6311 and DAC5311 TI DACs, with
DT bindings.
* vcnl5035
- New driver supporting the light sensor part of the VCNL4035, with
DT bindings
Features,
* bindings
- Add a generic ADC channel binding as we keep reinventing this
wheel.
* adc128s052
- Add IDs for additional pin compatible parts.
- Add APCI ID seen on E3940 UP squared boards.
* ad_sigma_delta
- Allow for custom data register overiding default.
* kxcjk1013
- Add KIOX0009 ACPI ID as seen on the Acer One 10.
* lsm6dsx
- Rework leading to...
- External sensor support using the built in I2C master.
- Initial support for a slave lis2mdl magnetometer.
* meson-saradc
- Add temperature sensor support and bindings.
* st_magn
- New ID for lsm9dsl_magn with bindings
- New ID for lis3de accelerometer
* tpl0102
- Add supprot for IIO_AVAIL_RANGE to report the range available
from this device to userspace and in kernel users.
Cleanups and minor fixes
* tools
- Allow outside specification of CFLAGS
* ad2s90
- Handle and spi_read error.
- Handle spi_setup failure
- Drop a pointless assignment.
- Prevent a potentail race by moving device registration to after
all other setup.
- Add missing scale attribute.
- Add a sanity check on channel type before trying to read it.
* ad2s1210
- Move to modern gpio descriptors.
- Drop a gpioin flag which made no sense as far as we can tell.
- Add dt table (bindings doc to follow when this is ready for
moving out of staging).
* ad5933
- Drop camel-case naming of ext_clk_hz.
- White space fixes.
* ad7150
- Local variable to shorten overly long line.
- Alignment and line break fixes.
* ad7280a
- Handle an error path that was previously ignored.
- Use crc8.h to build the crc table replacing custom code.
- Avoid unecessary cast.
- Power down the device if an error happens in probe
- Use devm routines to simplify probe and remove.
* ad7606
- Alignment fixes.
* ad7780
- This worked as long as by coincidence an uninitialized value
was 0. Lets not rely on that.
- Ensure gain update is only used with the ad778x chips that
actually support it.
- Tidy up pattern mask generation.
- Read regulator when scale is requested (which should be infrequent)
as it might have changed from initialization.
* ad7816
- Move to modern gpio descriptors
- Don't use a busy_pin for ad7818 as there isn't one.
- Ensure RD/WR and CONVST pins are outputs (previously they
were brought up as inputs which doesn't seem to make any sense)
- DT id table.
* adc128s052
- SPDX
* adt7316
- Alignment fix.
- Fix data reading. When using I2C the driver never actually
used the value read. This has been broken a very long time
hence no rush to fix it now + the driver is undergoing a lot
of cleanup.
- Sanity check that the i2c read didn't fail to actually read
anything.
* dpot-dac
- Mark a switch full through with slightly different text so that
gcc doesn't warn on it.
* gyro-adc
- Fix a wrong file in the MAINTAINERS entry and add binding doc to the
listed files.
* ina2xx
- Add some early returns to clarify error paths in switch.
* lsm6dsx
- MAINTAINERS entry.
* max11100
- SPDX
* max9611
- SPDX
* mcp4131
- use of_device_get_match_data in preference to spi_get_device_id
approach.
* rcar-adc
- SPDX
* sc27xx
- Add ADC conversion timeout support to avoid possible fault.
* ssp_sensors
- Don't free managed resources manually.
* st-magn
- Add a comment to avoid future confusion over when to use -magn
postfix (on multi chip in package parts)
- Add BDU register for LIS3MDL where it seems to have been missed.
* st-sensors
- Minor spelling, grammar etc fixes.
* tpl0102
- Use a pointer rather than an index of an array to improve conciseness.
* tag 'iio-for-4.21a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio: (80 commits)
Staging: iio: adt7316: Add an extra check for 'ret' equals to 0
Staging: iio: adt7316: Fix i2c data reading, set the data field
dt-bindings: iio: adc: Add docs for ad7124
iio: adc: Add ad7124 support
dt-bindings: iio: adc: Add common ADCs properties to a separate file
iio: ad_sigma_delta: Allow to provide custom data register address
staging: iio: ad7816: Add device tree table.
iio: imu: st_lsm6dsx: add entry in MAINTAINERS file
iio: potentiometer: mcp4131: use of_device_get_match_data()
staging: iio: adc: ad7280a: use devm_* APIs
staging: iio: adc: ad7280a: power down the device on error in probe
dt-bindings: iio: imu: st_lsm6dsx: add support to i2c pullup resistors
iio: imu: st_lsm6dsx: add hw FIFO support to i2c controller
iio: imu: st_lsm6dsx: add st_lsm6dsx_push_tagged_data routine
iio: imu: st_lsm6dsx: add i2c embedded controller support
iio: imu: st_lsm6dsx: introduce st_lsm6dsx_sensor_set_enable routine
iio: imu: st_lsm6dsx: introduce ST_LSM6DSX_ID_EXT sensor ids
iio: imu: st_lsm6dsx: remove static from st_lsm6dsx_set_watermark
iio: imu: st_lsm6dsx: reload trimming parameter at bootstrap
iio: imu: st_lsm6dsx: introduce locked read/write utility routines
...
Diffstat (limited to 'drivers/iio/adc/ad7949.c')
-rw-r--r-- | drivers/iio/adc/ad7949.c | 347 |
1 files changed, 347 insertions, 0 deletions
diff --git a/drivers/iio/adc/ad7949.c b/drivers/iio/adc/ad7949.c new file mode 100644 index 000000000000..ac0ffff6c5ae --- /dev/null +++ b/drivers/iio/adc/ad7949.c @@ -0,0 +1,347 @@ +// SPDX-License-Identifier: GPL-2.0 +/* ad7949.c - Analog Devices ADC driver 14/16 bits 4/8 channels + * + * Copyright (C) 2018 CMC NV + * + * http://www.analog.com/media/en/technical-documentation/data-sheets/AD7949.pdf + */ + +#include <linux/delay.h> +#include <linux/iio/iio.h> +#include <linux/module.h> +#include <linux/regulator/consumer.h> +#include <linux/spi/spi.h> + +#define AD7949_MASK_CHANNEL_SEL GENMASK(9, 7) +#define AD7949_MASK_TOTAL GENMASK(13, 0) +#define AD7949_OFFSET_CHANNEL_SEL 7 +#define AD7949_CFG_READ_BACK 0x1 +#define AD7949_CFG_REG_SIZE_BITS 14 + +enum { + ID_AD7949 = 0, + ID_AD7682, + ID_AD7689, +}; + +struct ad7949_adc_spec { + u8 num_channels; + u8 resolution; +}; + +static const struct ad7949_adc_spec ad7949_adc_spec[] = { + [ID_AD7949] = { .num_channels = 8, .resolution = 14 }, + [ID_AD7682] = { .num_channels = 4, .resolution = 16 }, + [ID_AD7689] = { .num_channels = 8, .resolution = 16 }, +}; + +/** + * struct ad7949_adc_chip - AD ADC chip + * @lock: protects write sequences + * @vref: regulator generating Vref + * @iio_dev: reference to iio structure + * @spi: reference to spi structure + * @resolution: resolution of the chip + * @cfg: copy of the configuration register + * @current_channel: current channel in use + * @buffer: buffer to send / receive data to / from device + */ +struct ad7949_adc_chip { + struct mutex lock; + struct regulator *vref; + struct iio_dev *indio_dev; + struct spi_device *spi; + u8 resolution; + u16 cfg; + unsigned int current_channel; + u32 buffer ____cacheline_aligned; +}; + +static bool ad7949_spi_cfg_is_read_back(struct ad7949_adc_chip *ad7949_adc) +{ + if (!(ad7949_adc->cfg & AD7949_CFG_READ_BACK)) + return true; + + return false; +} + +static int ad7949_spi_bits_per_word(struct ad7949_adc_chip *ad7949_adc) +{ + int ret = ad7949_adc->resolution; + + if (ad7949_spi_cfg_is_read_back(ad7949_adc)) + ret += AD7949_CFG_REG_SIZE_BITS; + + return ret; +} + +static int ad7949_spi_write_cfg(struct ad7949_adc_chip *ad7949_adc, u16 val, + u16 mask) +{ + int ret; + int bits_per_word = ad7949_spi_bits_per_word(ad7949_adc); + int shift = bits_per_word - AD7949_CFG_REG_SIZE_BITS; + struct spi_message msg; + struct spi_transfer tx[] = { + { + .tx_buf = &ad7949_adc->buffer, + .len = 4, + .bits_per_word = bits_per_word, + }, + }; + + ad7949_adc->cfg = (val & mask) | (ad7949_adc->cfg & ~mask); + ad7949_adc->buffer = ad7949_adc->cfg << shift; + spi_message_init_with_transfers(&msg, tx, 1); + ret = spi_sync(ad7949_adc->spi, &msg); + + /* + * This delay is to avoid a new request before the required time to + * send a new command to the device + */ + udelay(2); + return ret; +} + +static int ad7949_spi_read_channel(struct ad7949_adc_chip *ad7949_adc, int *val, + unsigned int channel) +{ + int ret; + int bits_per_word = ad7949_spi_bits_per_word(ad7949_adc); + int mask = GENMASK(ad7949_adc->resolution, 0); + struct spi_message msg; + struct spi_transfer tx[] = { + { + .rx_buf = &ad7949_adc->buffer, + .len = 4, + .bits_per_word = bits_per_word, + }, + }; + + ret = ad7949_spi_write_cfg(ad7949_adc, + channel << AD7949_OFFSET_CHANNEL_SEL, + AD7949_MASK_CHANNEL_SEL); + if (ret) + return ret; + + ad7949_adc->buffer = 0; + spi_message_init_with_transfers(&msg, tx, 1); + ret = spi_sync(ad7949_adc->spi, &msg); + if (ret) + return ret; + + /* + * This delay is to avoid a new request before the required time to + * send a new command to the device + */ + udelay(2); + + ad7949_adc->current_channel = channel; + + if (ad7949_spi_cfg_is_read_back(ad7949_adc)) + *val = (ad7949_adc->buffer >> AD7949_CFG_REG_SIZE_BITS) & mask; + else + *val = ad7949_adc->buffer & mask; + + return 0; +} + +#define AD7949_ADC_CHANNEL(chan) { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .channel = (chan), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ +} + +static const struct iio_chan_spec ad7949_adc_channels[] = { + AD7949_ADC_CHANNEL(0), + AD7949_ADC_CHANNEL(1), + AD7949_ADC_CHANNEL(2), + AD7949_ADC_CHANNEL(3), + AD7949_ADC_CHANNEL(4), + AD7949_ADC_CHANNEL(5), + AD7949_ADC_CHANNEL(6), + AD7949_ADC_CHANNEL(7), +}; + +static int ad7949_spi_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct ad7949_adc_chip *ad7949_adc = iio_priv(indio_dev); + int ret; + + if (!val) + return -EINVAL; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&ad7949_adc->lock); + ret = ad7949_spi_read_channel(ad7949_adc, val, chan->channel); + mutex_unlock(&ad7949_adc->lock); + + if (ret < 0) + return ret; + + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + ret = regulator_get_voltage(ad7949_adc->vref); + if (ret < 0) + return ret; + + *val = ret / 5000; + return IIO_VAL_INT; + } + + return -EINVAL; +} + +static int ad7949_spi_reg_access(struct iio_dev *indio_dev, + unsigned int reg, unsigned int writeval, + unsigned int *readval) +{ + struct ad7949_adc_chip *ad7949_adc = iio_priv(indio_dev); + int ret = 0; + + if (readval) + *readval = ad7949_adc->cfg; + else + ret = ad7949_spi_write_cfg(ad7949_adc, + writeval & AD7949_MASK_TOTAL, AD7949_MASK_TOTAL); + + return ret; +} + +static const struct iio_info ad7949_spi_info = { + .read_raw = ad7949_spi_read_raw, + .debugfs_reg_access = ad7949_spi_reg_access, +}; + +static int ad7949_spi_init(struct ad7949_adc_chip *ad7949_adc) +{ + int ret; + int val; + + /* Sequencer disabled, CFG readback disabled, IN0 as default channel */ + ad7949_adc->current_channel = 0; + ret = ad7949_spi_write_cfg(ad7949_adc, 0x3C79, AD7949_MASK_TOTAL); + + /* + * Do two dummy conversions to apply the first configuration setting. + * Required only after the start up of the device. + */ + ad7949_spi_read_channel(ad7949_adc, &val, ad7949_adc->current_channel); + ad7949_spi_read_channel(ad7949_adc, &val, ad7949_adc->current_channel); + + return ret; +} + +static int ad7949_spi_probe(struct spi_device *spi) +{ + struct device *dev = &spi->dev; + const struct ad7949_adc_spec *spec; + struct ad7949_adc_chip *ad7949_adc; + struct iio_dev *indio_dev; + int ret; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*ad7949_adc)); + if (!indio_dev) { + dev_err(dev, "can not allocate iio device\n"); + return -ENOMEM; + } + + indio_dev->dev.parent = dev; + indio_dev->dev.of_node = dev->of_node; + indio_dev->info = &ad7949_spi_info; + indio_dev->name = spi_get_device_id(spi)->name; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = ad7949_adc_channels; + spi_set_drvdata(spi, indio_dev); + + ad7949_adc = iio_priv(indio_dev); + ad7949_adc->indio_dev = indio_dev; + ad7949_adc->spi = spi; + + spec = &ad7949_adc_spec[spi_get_device_id(spi)->driver_data]; + indio_dev->num_channels = spec->num_channels; + ad7949_adc->resolution = spec->resolution; + + ad7949_adc->vref = devm_regulator_get(dev, "vref"); + if (IS_ERR(ad7949_adc->vref)) { + dev_err(dev, "fail to request regulator\n"); + return PTR_ERR(ad7949_adc->vref); + } + + ret = regulator_enable(ad7949_adc->vref); + if (ret < 0) { + dev_err(dev, "fail to enable regulator\n"); + return ret; + } + + mutex_init(&ad7949_adc->lock); + + ret = ad7949_spi_init(ad7949_adc); + if (ret) { + dev_err(dev, "enable to init this device: %d\n", ret); + goto err; + } + + 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(&ad7949_adc->lock); + regulator_disable(ad7949_adc->vref); + + return ret; +} + +static int ad7949_spi_remove(struct spi_device *spi) +{ + struct iio_dev *indio_dev = spi_get_drvdata(spi); + struct ad7949_adc_chip *ad7949_adc = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + mutex_destroy(&ad7949_adc->lock); + regulator_disable(ad7949_adc->vref); + + return 0; +} + +static const struct of_device_id ad7949_spi_of_id[] = { + { .compatible = "adi,ad7949" }, + { .compatible = "adi,ad7682" }, + { .compatible = "adi,ad7689" }, + { } +}; +MODULE_DEVICE_TABLE(of, ad7949_spi_of_id); + +static const struct spi_device_id ad7949_spi_id[] = { + { "ad7949", ID_AD7949 }, + { "ad7682", ID_AD7682 }, + { "ad7689", ID_AD7689 }, + { } +}; +MODULE_DEVICE_TABLE(spi, ad7949_spi_id); + +static struct spi_driver ad7949_spi_driver = { + .driver = { + .name = "ad7949", + .of_match_table = ad7949_spi_of_id, + }, + .probe = ad7949_spi_probe, + .remove = ad7949_spi_remove, + .id_table = ad7949_spi_id, +}; +module_spi_driver(ad7949_spi_driver); + +MODULE_AUTHOR("Charles-Antoine Couret <charles-antoine.couret@essensium.com>"); +MODULE_DESCRIPTION("Analog Devices 14/16-bit 8-channel ADC driver"); +MODULE_LICENSE("GPL v2"); |