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author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-06 00:50:51 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-06 00:50:51 +0300 |
commit | 41844e36206be90cd4d962ea49b0abc3612a99d0 (patch) | |
tree | ce0b3a3403bc6abdb28f52779d0d7b57a51a5c86 /drivers/iio/dac/ad8801.c | |
parent | 5691f0e9a3e7855832d5fd094801bf600347c2d0 (diff) | |
parent | fc1e2c8ea85e109acf09e74789e9b852f6eed251 (diff) | |
download | linux-41844e36206be90cd4d962ea49b0abc3612a99d0.tar.xz |
Merge tag 'staging-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging and IIO updates from Greg KH:
"Here is the big staging and IIO driver pull request for 4.9-rc1.
There are a lot of patches in here, the majority due to the
drivers/staging/greybus/ subsystem being merged in with full
development history that went back a few years, in order to preserve
the work that those developers did over time.
Lots and lots of tiny cleanups happened in the tree as well, due to
the Outreachy application process and lots of other developers showing
up for the first time to clean code up. Along with those changes, we
deleted a wireless driver, and added a raspberrypi driver (currently
marked broken), and lots of new iio drivers.
Overall the tree still shrunk with more lines removed than added,
about 10 thousand lines removed in total. Full details are in the very
long shortlog below.
All of this has been in the linux-next tree with no issues. There will
be some merge problems with other subsystem trees, but those are all
minor problems and shouldn't be hard to work out when they happen
(MAINTAINERS and some lustre build problems with the IB tree)"
And furter from me asking for clarification about greybus:
"Right now there is a phone from Motorola shipping with this code (a
slightly older version, but the same tree), so even though Ara is not
alive in the same form, the functionality is happening. We are working
with the developers of that phone to merge the newer stuff in with
their fork so they can use the upstream version in future versions of
their phone product line.
Toshiba has at least one chip shipping in their catalog that
needs/uses this protocol over a Unipro link, and rumor has it that
there might be more in the future.
There are also other users of the greybus protocols, there is a talk
next week at ELC that shows how it is being used across a network
connection to control a device, and previous ELC talks have showed the
protocol stack being used over USB to drive embedded Linux boards.
I've also talked to some people who are starting to work to add a host
controller driver to control arduinos as the greybus PHY protocols are
very useful to control a serial/i2c/spio/whatever device across a
random physical link, as it is a way to have a self-describing device
be attached to a host without needing manual configuration.
So yes, people are using it, and there is still the chance that it
will show up in a phone/laptop/tablet/whatever from Google in the
future as well, the tech isn't dead, even if the original large phone
project happens to be"
* tag 'staging-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (3703 commits)
Staging: fbtft: Fix bug in fbtft-core
staging: rtl8188eu: fix double unlock error in rtw_resume_process()
staging:r8188eu: remove GEN_MLME_EXT_HANDLER macro
staging:r8188eu: remove GEN_DRV_CMD_HANDLER macro
staging:r8188eu: remove GEN_EVT_CODE macro
staging:r8188eu: remove GEN_CMD_CODE macro
staging:r8188eu: remove pkt_newalloc member of the recv_buf structure
staging:r8188eu: remove rtw_handle_dualmac declaration
staging:r8188eu: remove (RGTRY|BSSID)_(OFT|SZ) macros
staging:r8188eu: change rtl8188e_process_phy_info function argument type
Staging: fsl-mc: Remove blank lines
Staging: fsl-mc: Fix unaligned * in block comments
Staging: comedi: Align the * in block comments
Staging : ks7010 : Fix block comments warninig
Staging: vt6655: Remove explicit NULL comparison using Coccinelle
staging: rtl8188eu: core: rtw_xmit: Use macros instead of constants
staging: rtl8188eu: core: rtw_xmit: Move constant of the right side
staging: dgnc: Fix lines longer than 80 characters
Staging: dgnc: constify attribute_group structures
Staging: most: hdm-dim2: constify attribute_group structures
...
Diffstat (limited to 'drivers/iio/dac/ad8801.c')
-rw-r--r-- | drivers/iio/dac/ad8801.c | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/drivers/iio/dac/ad8801.c b/drivers/iio/dac/ad8801.c new file mode 100644 index 000000000000..f06faa1aec09 --- /dev/null +++ b/drivers/iio/dac/ad8801.c @@ -0,0 +1,239 @@ +/* + * IIO DAC driver for Analog Devices AD8801 DAC + * + * Copyright (C) 2016 Gwenhael Goavec-Merou + * 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. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + */ + +#include <linux/iio/iio.h> +#include <linux/module.h> +#include <linux/regulator/consumer.h> +#include <linux/spi/spi.h> +#include <linux/sysfs.h> + +#define AD8801_CFG_ADDR_OFFSET 8 + +enum ad8801_device_ids { + ID_AD8801, + ID_AD8803, +}; + +struct ad8801_state { + struct spi_device *spi; + unsigned char dac_cache[8]; /* Value write on each channel */ + unsigned int vrefh_mv; + unsigned int vrefl_mv; + struct regulator *vrefh_reg; + struct regulator *vrefl_reg; + + __be16 data ____cacheline_aligned; +}; + +static int ad8801_spi_write(struct ad8801_state *state, + u8 channel, unsigned char value) +{ + state->data = cpu_to_be16((channel << AD8801_CFG_ADDR_OFFSET) | value); + return spi_write(state->spi, &state->data, sizeof(state->data)); +} + +static int ad8801_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int val, int val2, long mask) +{ + struct ad8801_state *state = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + if (val >= 256 || val < 0) + return -EINVAL; + + ret = ad8801_spi_write(state, chan->channel, val); + if (ret == 0) + state->dac_cache[chan->channel] = val; + break; + default: + ret = -EINVAL; + } + + return ret; +} + +static int ad8801_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, int *val2, long info) +{ + struct ad8801_state *state = iio_priv(indio_dev); + + switch (info) { + case IIO_CHAN_INFO_RAW: + *val = state->dac_cache[chan->channel]; + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + *val = state->vrefh_mv - state->vrefl_mv; + *val2 = 8; + return IIO_VAL_FRACTIONAL_LOG2; + case IIO_CHAN_INFO_OFFSET: + *val = state->vrefl_mv; + return IIO_VAL_INT; + default: + return -EINVAL; + } + + return -EINVAL; +} + +static const struct iio_info ad8801_info = { + .read_raw = ad8801_read_raw, + .write_raw = ad8801_write_raw, + .driver_module = THIS_MODULE, +}; + +#define AD8801_CHANNEL(chan) { \ + .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) | \ + BIT(IIO_CHAN_INFO_OFFSET), \ +} + +static const struct iio_chan_spec ad8801_channels[] = { + AD8801_CHANNEL(0), + AD8801_CHANNEL(1), + AD8801_CHANNEL(2), + AD8801_CHANNEL(3), + AD8801_CHANNEL(4), + AD8801_CHANNEL(5), + AD8801_CHANNEL(6), + AD8801_CHANNEL(7), +}; + +static int ad8801_probe(struct spi_device *spi) +{ + struct iio_dev *indio_dev; + struct ad8801_state *state; + const struct spi_device_id *id; + int ret; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*state)); + if (indio_dev == NULL) + return -ENOMEM; + + state = iio_priv(indio_dev); + state->spi = spi; + id = spi_get_device_id(spi); + + state->vrefh_reg = devm_regulator_get(&spi->dev, "vrefh"); + if (IS_ERR(state->vrefh_reg)) { + dev_err(&spi->dev, "Vrefh regulator not specified\n"); + return PTR_ERR(state->vrefh_reg); + } + + ret = regulator_enable(state->vrefh_reg); + if (ret) { + dev_err(&spi->dev, "Failed to enable vrefh regulator: %d\n", + ret); + return ret; + } + + ret = regulator_get_voltage(state->vrefh_reg); + if (ret < 0) { + dev_err(&spi->dev, "Failed to read vrefh regulator: %d\n", + ret); + goto error_disable_vrefh_reg; + } + state->vrefh_mv = ret / 1000; + + if (id->driver_data == ID_AD8803) { + state->vrefl_reg = devm_regulator_get(&spi->dev, "vrefl"); + if (IS_ERR(state->vrefl_reg)) { + dev_err(&spi->dev, "Vrefl regulator not specified\n"); + ret = PTR_ERR(state->vrefl_reg); + goto error_disable_vrefh_reg; + } + + ret = regulator_enable(state->vrefl_reg); + if (ret) { + dev_err(&spi->dev, "Failed to enable vrefl regulator: %d\n", + ret); + goto error_disable_vrefh_reg; + } + + ret = regulator_get_voltage(state->vrefl_reg); + if (ret < 0) { + dev_err(&spi->dev, "Failed to read vrefl regulator: %d\n", + ret); + goto error_disable_vrefl_reg; + } + state->vrefl_mv = ret / 1000; + } else { + state->vrefl_mv = 0; + state->vrefl_reg = NULL; + } + + spi_set_drvdata(spi, indio_dev); + indio_dev->dev.parent = &spi->dev; + indio_dev->info = &ad8801_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = ad8801_channels; + indio_dev->num_channels = ARRAY_SIZE(ad8801_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_vrefl_reg; + } + + return 0; + +error_disable_vrefl_reg: + if (state->vrefl_reg) + regulator_disable(state->vrefl_reg); +error_disable_vrefh_reg: + regulator_disable(state->vrefh_reg); + return ret; +} + +static int ad8801_remove(struct spi_device *spi) +{ + struct iio_dev *indio_dev = spi_get_drvdata(spi); + struct ad8801_state *state = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + if (state->vrefl_reg) + regulator_disable(state->vrefl_reg); + regulator_disable(state->vrefh_reg); + + return 0; +} + +static const struct spi_device_id ad8801_ids[] = { + {"ad8801", ID_AD8801}, + {"ad8803", ID_AD8803}, + {} +}; +MODULE_DEVICE_TABLE(spi, ad8801_ids); + +static struct spi_driver ad8801_driver = { + .driver = { + .name = "ad8801", + }, + .probe = ad8801_probe, + .remove = ad8801_remove, + .id_table = ad8801_ids, +}; +module_spi_driver(ad8801_driver); + +MODULE_AUTHOR("Gwenhael Goavec-Merou <gwenhael.goavec-merou@trabucayre.com>"); +MODULE_DESCRIPTION("Analog Devices AD8801/AD8803 DAC"); +MODULE_LICENSE("GPL v2"); |