diff options
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/adc/ti-adc12138.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/adc/ti-adc12138.c')
-rw-r--r-- | drivers/iio/adc/ti-adc12138.c | 552 |
1 files changed, 552 insertions, 0 deletions
diff --git a/drivers/iio/adc/ti-adc12138.c b/drivers/iio/adc/ti-adc12138.c new file mode 100644 index 000000000000..072f03bfe6a0 --- /dev/null +++ b/drivers/iio/adc/ti-adc12138.c @@ -0,0 +1,552 @@ +/* + * ADC12130/ADC12132/ADC12138 12-bit plus sign ADC driver + * + * Copyright (c) 2016 Akinobu Mita <akinobu.mita@gmail.com> + * + * This file is subject to the terms and conditions of version 2 of + * the GNU General Public License. See the file COPYING in the main + * directory of this archive for more details. + * + * Datasheet: http://www.ti.com/lit/ds/symlink/adc12138.pdf + */ + +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/completion.h> +#include <linux/clk.h> +#include <linux/spi/spi.h> +#include <linux/iio/iio.h> +#include <linux/iio/buffer.h> +#include <linux/iio/trigger.h> +#include <linux/iio/triggered_buffer.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/regulator/consumer.h> + +#define ADC12138_MODE_AUTO_CAL 0x08 +#define ADC12138_MODE_READ_STATUS 0x0c +#define ADC12138_MODE_ACQUISITION_TIME_6 0x0e +#define ADC12138_MODE_ACQUISITION_TIME_10 0x4e +#define ADC12138_MODE_ACQUISITION_TIME_18 0x8e +#define ADC12138_MODE_ACQUISITION_TIME_34 0xce + +#define ADC12138_STATUS_CAL BIT(6) + +enum { + adc12130, + adc12132, + adc12138, +}; + +struct adc12138 { + struct spi_device *spi; + unsigned int id; + /* conversion clock */ + struct clk *cclk; + /* positive analog voltage reference */ + struct regulator *vref_p; + /* negative analog voltage reference */ + struct regulator *vref_n; + struct mutex lock; + struct completion complete; + /* The number of cclk periods for the S/H's acquisition time */ + unsigned int acquisition_time; + + u8 tx_buf[2] ____cacheline_aligned; + u8 rx_buf[2]; +}; + +#define ADC12138_VOLTAGE_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) \ + | BIT(IIO_CHAN_INFO_OFFSET), \ + .scan_index = chan, \ + .scan_type = { \ + .sign = 's', \ + .realbits = 13, \ + .storagebits = 16, \ + .shift = 3, \ + .endianness = IIO_BE, \ + }, \ + } + +#define ADC12138_VOLTAGE_CHANNEL_DIFF(chan1, chan2, si) \ + { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .channel = (chan1), \ + .channel2 = (chan2), \ + .differential = 1, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \ + | BIT(IIO_CHAN_INFO_OFFSET), \ + .scan_index = si, \ + .scan_type = { \ + .sign = 's', \ + .realbits = 13, \ + .storagebits = 16, \ + .shift = 3, \ + .endianness = IIO_BE, \ + }, \ + } + +static const struct iio_chan_spec adc12132_channels[] = { + ADC12138_VOLTAGE_CHANNEL(0), + ADC12138_VOLTAGE_CHANNEL(1), + ADC12138_VOLTAGE_CHANNEL_DIFF(0, 1, 2), + ADC12138_VOLTAGE_CHANNEL_DIFF(1, 0, 3), + IIO_CHAN_SOFT_TIMESTAMP(4), +}; + +static const struct iio_chan_spec adc12138_channels[] = { + ADC12138_VOLTAGE_CHANNEL(0), + ADC12138_VOLTAGE_CHANNEL(1), + ADC12138_VOLTAGE_CHANNEL(2), + ADC12138_VOLTAGE_CHANNEL(3), + ADC12138_VOLTAGE_CHANNEL(4), + ADC12138_VOLTAGE_CHANNEL(5), + ADC12138_VOLTAGE_CHANNEL(6), + ADC12138_VOLTAGE_CHANNEL(7), + ADC12138_VOLTAGE_CHANNEL_DIFF(0, 1, 8), + ADC12138_VOLTAGE_CHANNEL_DIFF(1, 0, 9), + ADC12138_VOLTAGE_CHANNEL_DIFF(2, 3, 10), + ADC12138_VOLTAGE_CHANNEL_DIFF(3, 2, 11), + ADC12138_VOLTAGE_CHANNEL_DIFF(4, 5, 12), + ADC12138_VOLTAGE_CHANNEL_DIFF(5, 4, 13), + ADC12138_VOLTAGE_CHANNEL_DIFF(6, 7, 14), + ADC12138_VOLTAGE_CHANNEL_DIFF(7, 6, 15), + IIO_CHAN_SOFT_TIMESTAMP(16), +}; + +static int adc12138_mode_programming(struct adc12138 *adc, u8 mode, + void *rx_buf, int len) +{ + struct spi_transfer xfer = { + .tx_buf = adc->tx_buf, + .rx_buf = adc->rx_buf, + .len = len, + }; + int ret; + + /* Skip unused bits for ADC12130 and ADC12132 */ + if (adc->id != adc12138) + mode = (mode & 0xc0) | ((mode & 0x0f) << 2); + + adc->tx_buf[0] = mode; + + ret = spi_sync_transfer(adc->spi, &xfer, 1); + if (ret) + return ret; + + memcpy(rx_buf, adc->rx_buf, len); + + return 0; +} + +static int adc12138_read_status(struct adc12138 *adc) +{ + u8 rx_buf[2]; + int ret; + + ret = adc12138_mode_programming(adc, ADC12138_MODE_READ_STATUS, + rx_buf, 2); + if (ret) + return ret; + + return (rx_buf[0] << 1) | (rx_buf[1] >> 7); +} + +static int __adc12138_start_conv(struct adc12138 *adc, + struct iio_chan_spec const *channel, + void *data, int len) + +{ + const u8 ch_to_mux[] = { 0, 4, 1, 5, 2, 6, 3, 7 }; + u8 mode = (ch_to_mux[channel->channel] << 4) | + (channel->differential ? 0 : 0x80); + + return adc12138_mode_programming(adc, mode, data, len); +} + +static int adc12138_start_conv(struct adc12138 *adc, + struct iio_chan_spec const *channel) +{ + u8 trash; + + return __adc12138_start_conv(adc, channel, &trash, 1); +} + +static int adc12138_start_and_read_conv(struct adc12138 *adc, + struct iio_chan_spec const *channel, + __be16 *data) +{ + return __adc12138_start_conv(adc, channel, data, 2); +} + +static int adc12138_read_conv_data(struct adc12138 *adc, __be16 *value) +{ + /* Issue a read status instruction and read previous conversion data */ + return adc12138_mode_programming(adc, ADC12138_MODE_READ_STATUS, + value, sizeof(*value)); +} + +static int adc12138_wait_eoc(struct adc12138 *adc, unsigned long timeout) +{ + if (!wait_for_completion_timeout(&adc->complete, timeout)) + return -ETIMEDOUT; + + return 0; +} + +static int adc12138_adc_conversion(struct adc12138 *adc, + struct iio_chan_spec const *channel, + __be16 *value) +{ + int ret; + + reinit_completion(&adc->complete); + + ret = adc12138_start_conv(adc, channel); + if (ret) + return ret; + + ret = adc12138_wait_eoc(adc, msecs_to_jiffies(100)); + if (ret) + return ret; + + return adc12138_read_conv_data(adc, value); +} + +static int adc12138_read_raw(struct iio_dev *iio, + struct iio_chan_spec const *channel, int *value, + int *shift, long mask) +{ + struct adc12138 *adc = iio_priv(iio); + int ret; + __be16 data; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&adc->lock); + ret = adc12138_adc_conversion(adc, channel, &data); + mutex_unlock(&adc->lock); + if (ret) + return ret; + + *value = sign_extend32(be16_to_cpu(data) >> 3, 12); + + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + ret = regulator_get_voltage(adc->vref_p); + if (ret < 0) + return ret; + *value = ret; + + if (!IS_ERR(adc->vref_n)) { + ret = regulator_get_voltage(adc->vref_n); + if (ret < 0) + return ret; + *value -= ret; + } + + /* convert regulator output voltage to mV */ + *value /= 1000; + *shift = channel->scan_type.realbits - 1; + + return IIO_VAL_FRACTIONAL_LOG2; + case IIO_CHAN_INFO_OFFSET: + if (!IS_ERR(adc->vref_n)) { + *value = regulator_get_voltage(adc->vref_n); + if (*value < 0) + return *value; + } else { + *value = 0; + } + + /* convert regulator output voltage to mV */ + *value /= 1000; + + return IIO_VAL_INT; + } + + return -EINVAL; +} + +static const struct iio_info adc12138_info = { + .read_raw = adc12138_read_raw, + .driver_module = THIS_MODULE, +}; + +static int adc12138_init(struct adc12138 *adc) +{ + int ret; + int status; + u8 mode; + u8 trash; + + reinit_completion(&adc->complete); + + ret = adc12138_mode_programming(adc, ADC12138_MODE_AUTO_CAL, &trash, 1); + if (ret) + return ret; + + /* data output at this time has no significance */ + status = adc12138_read_status(adc); + if (status < 0) + return status; + + adc12138_wait_eoc(adc, msecs_to_jiffies(100)); + + status = adc12138_read_status(adc); + if (status & ADC12138_STATUS_CAL) { + dev_warn(&adc->spi->dev, + "Auto Cal sequence is still in progress: %#x\n", + status); + return -EIO; + } + + switch (adc->acquisition_time) { + case 6: + mode = ADC12138_MODE_ACQUISITION_TIME_6; + break; + case 10: + mode = ADC12138_MODE_ACQUISITION_TIME_10; + break; + case 18: + mode = ADC12138_MODE_ACQUISITION_TIME_18; + break; + case 34: + mode = ADC12138_MODE_ACQUISITION_TIME_34; + break; + default: + return -EINVAL; + } + + return adc12138_mode_programming(adc, mode, &trash, 1); +} + +static irqreturn_t adc12138_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct adc12138 *adc = iio_priv(indio_dev); + __be16 data[20] = { }; /* 16x 2 bytes ADC data + 8 bytes timestamp */ + __be16 trash; + int ret; + int scan_index; + int i = 0; + + mutex_lock(&adc->lock); + + for_each_set_bit(scan_index, indio_dev->active_scan_mask, + indio_dev->masklength) { + const struct iio_chan_spec *scan_chan = + &indio_dev->channels[scan_index]; + + reinit_completion(&adc->complete); + + ret = adc12138_start_and_read_conv(adc, scan_chan, + i ? &data[i - 1] : &trash); + if (ret) { + dev_warn(&adc->spi->dev, + "failed to start conversion\n"); + goto out; + } + + ret = adc12138_wait_eoc(adc, msecs_to_jiffies(100)); + if (ret) { + dev_warn(&adc->spi->dev, "wait eoc timeout\n"); + goto out; + } + + i++; + } + + if (i) { + ret = adc12138_read_conv_data(adc, &data[i - 1]); + if (ret) { + dev_warn(&adc->spi->dev, + "failed to get conversion data\n"); + goto out; + } + } + + iio_push_to_buffers_with_timestamp(indio_dev, data, + iio_get_time_ns(indio_dev)); +out: + mutex_unlock(&adc->lock); + + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +static irqreturn_t adc12138_eoc_handler(int irq, void *p) +{ + struct iio_dev *indio_dev = p; + struct adc12138 *adc = iio_priv(indio_dev); + + complete(&adc->complete); + + return IRQ_HANDLED; +} + +static int adc12138_probe(struct spi_device *spi) +{ + struct iio_dev *indio_dev; + struct adc12138 *adc; + int ret; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc)); + if (!indio_dev) + return -ENOMEM; + + adc = iio_priv(indio_dev); + adc->spi = spi; + adc->id = spi_get_device_id(spi)->driver_data; + mutex_init(&adc->lock); + init_completion(&adc->complete); + + indio_dev->name = spi_get_device_id(spi)->name; + indio_dev->dev.parent = &spi->dev; + indio_dev->info = &adc12138_info; + indio_dev->modes = INDIO_DIRECT_MODE; + + switch (adc->id) { + case adc12130: + case adc12132: + indio_dev->channels = adc12132_channels; + indio_dev->num_channels = ARRAY_SIZE(adc12132_channels); + break; + case adc12138: + indio_dev->channels = adc12138_channels; + indio_dev->num_channels = ARRAY_SIZE(adc12138_channels); + break; + default: + return -EINVAL; + } + + ret = of_property_read_u32(spi->dev.of_node, "ti,acquisition-time", + &adc->acquisition_time); + if (ret) + adc->acquisition_time = 10; + + adc->cclk = devm_clk_get(&spi->dev, NULL); + if (IS_ERR(adc->cclk)) + return PTR_ERR(adc->cclk); + + adc->vref_p = devm_regulator_get(&spi->dev, "vref-p"); + if (IS_ERR(adc->vref_p)) + return PTR_ERR(adc->vref_p); + + adc->vref_n = devm_regulator_get_optional(&spi->dev, "vref-n"); + if (IS_ERR(adc->vref_n)) { + /* + * Assume vref_n is 0V if an optional regulator is not + * specified, otherwise return the error code. + */ + ret = PTR_ERR(adc->vref_n); + if (ret != -ENODEV) + return ret; + } + + ret = devm_request_irq(&spi->dev, spi->irq, adc12138_eoc_handler, + IRQF_TRIGGER_RISING, indio_dev->name, indio_dev); + if (ret) + return ret; + + ret = clk_prepare_enable(adc->cclk); + if (ret) + return ret; + + ret = regulator_enable(adc->vref_p); + if (ret) + goto err_clk_disable; + + if (!IS_ERR(adc->vref_n)) { + ret = regulator_enable(adc->vref_n); + if (ret) + goto err_vref_p_disable; + } + + ret = adc12138_init(adc); + if (ret) + goto err_vref_n_disable; + + spi_set_drvdata(spi, indio_dev); + + ret = iio_triggered_buffer_setup(indio_dev, NULL, + adc12138_trigger_handler, NULL); + if (ret) + goto err_vref_n_disable; + + ret = iio_device_register(indio_dev); + if (ret) + goto err_buffer_cleanup; + + return 0; +err_buffer_cleanup: + iio_triggered_buffer_cleanup(indio_dev); +err_vref_n_disable: + if (!IS_ERR(adc->vref_n)) + regulator_disable(adc->vref_n); +err_vref_p_disable: + regulator_disable(adc->vref_p); +err_clk_disable: + clk_disable_unprepare(adc->cclk); + + return ret; +} + +static int adc12138_remove(struct spi_device *spi) +{ + struct iio_dev *indio_dev = spi_get_drvdata(spi); + struct adc12138 *adc = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + iio_triggered_buffer_cleanup(indio_dev); + if (!IS_ERR(adc->vref_n)) + regulator_disable(adc->vref_n); + regulator_disable(adc->vref_p); + clk_disable_unprepare(adc->cclk); + + return 0; +} + +#ifdef CONFIG_OF + +static const struct of_device_id adc12138_dt_ids[] = { + { .compatible = "ti,adc12130", }, + { .compatible = "ti,adc12132", }, + { .compatible = "ti,adc12138", }, + {} +}; +MODULE_DEVICE_TABLE(of, adc12138_dt_ids); + +#endif + +static const struct spi_device_id adc12138_id[] = { + { "adc12130", adc12130 }, + { "adc12132", adc12132 }, + { "adc12138", adc12138 }, + {} +}; +MODULE_DEVICE_TABLE(spi, adc12138_id); + +static struct spi_driver adc12138_driver = { + .driver = { + .name = "adc12138", + .of_match_table = of_match_ptr(adc12138_dt_ids), + }, + .probe = adc12138_probe, + .remove = adc12138_remove, + .id_table = adc12138_id, +}; +module_spi_driver(adc12138_driver); + +MODULE_AUTHOR("Akinobu Mita <akinobu.mita@gmail.com>"); +MODULE_DESCRIPTION("ADC12130/ADC12132/ADC12138 driver"); +MODULE_LICENSE("GPL v2"); |