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author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-08-04 18:36:12 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-08-04 18:36:12 -0700 |
commit | 53ee983378ff23e8f3ff95ecf99dea7c6c221900 (patch) | |
tree | 85e09b2bf6317a155f1405be0d45c69051b6e041 /drivers/iio/adc/max1027.c | |
parent | 29b88e23a9212136d39b0161a39afe587d0170a5 (diff) | |
parent | b9aaea39f65e242303103b5283abeaefd8e538a4 (diff) | |
download | linux-53ee983378ff23e8f3ff95ecf99dea7c6c221900.tar.gz linux-53ee983378ff23e8f3ff95ecf99dea7c6c221900.tar.bz2 linux-53ee983378ff23e8f3ff95ecf99dea7c6c221900.zip |
Merge tag 'staging-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging driver updates from Greg KH:
"Here's the big pull request for the staging driver tree for 3.17-rc1.
Lots of things in here, over 2000 patches, but the best part is this:
1480 files changed, 39070 insertions(+), 254659 deletions(-)
Thanks to the great work of Kristina Martšenko, 14 different staging
drivers have been removed from the tree as they were obsolete and no
one was willing to work on cleaning them up. Other than the driver
removals, loads of cleanups are in here (comedi, lustre, etc.) as well
as the usual IIO driver updates and additions.
All of this has been in the linux-next tree for a while"
* tag 'staging-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (2199 commits)
staging: comedi: addi_apci_1564: remove diagnostic interrupt support code
staging: comedi: addi_apci_1564: add subdevice to check diagnostic status
staging: wlan-ng: coding style problem fix
staging: wlan-ng: fixing coding style problems
staging: comedi: ii_pci20kc: request and ioremap memory
staging: lustre: bitwise vs logical typo
staging: dgnc: Remove unneeded dgnc_trace.c and dgnc_trace.h
staging: dgnc: rephrase comment
staging: comedi: ni_tio: remove some dead code
staging: rtl8723au: Fix static symbol sparse warning
staging: rtl8723au: usb_dvobj_init(): Remove unused variable 'pdev_desc'
staging: rtl8723au: Do not duplicate kernel provided USB macros
staging: rtl8723au: Remove never set struct pwrctrl_priv.bHWPowerdown
staging: rtl8723au: Remove two never set variables
staging: rtl8723au: RSSI_test is never set
staging:r8190: coding style: Fixed checkpatch reported Error
staging:r8180: coding style: Fixed too long lines
staging:r8180: coding style: Fixed commenting style
staging: lustre: ptlrpc: lproc_ptlrpc.c - fix dereferenceing user space buffer
staging: lustre: ldlm: ldlm_resource.c - fix dereferenceing user space buffer
...
Diffstat (limited to 'drivers/iio/adc/max1027.c')
-rw-r--r-- | drivers/iio/adc/max1027.c | 521 |
1 files changed, 521 insertions, 0 deletions
diff --git a/drivers/iio/adc/max1027.c b/drivers/iio/adc/max1027.c new file mode 100644 index 000000000000..87ee1c7d0b54 --- /dev/null +++ b/drivers/iio/adc/max1027.c @@ -0,0 +1,521 @@ + /* + * iio/adc/max1027.c + * Copyright (C) 2014 Philippe Reynes + * + * based on linux/drivers/iio/ad7923.c + * Copyright 2011 Analog Devices Inc (from AD7923 Driver) + * Copyright 2012 CS Systemes d'Information + * + * 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. + * + * max1027.c + * + * Partial support for max1027 and similar chips. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/spi/spi.h> +#include <linux/delay.h> + +#include <linux/iio/iio.h> +#include <linux/iio/buffer.h> +#include <linux/iio/trigger.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> + +#define MAX1027_CONV_REG BIT(7) +#define MAX1027_SETUP_REG BIT(6) +#define MAX1027_AVG_REG BIT(5) +#define MAX1027_RST_REG BIT(4) + +/* conversion register */ +#define MAX1027_TEMP BIT(0) +#define MAX1027_SCAN_0_N (0x00 << 1) +#define MAX1027_SCAN_N_M (0x01 << 1) +#define MAX1027_SCAN_N (0x02 << 1) +#define MAX1027_NOSCAN (0x03 << 1) +#define MAX1027_CHAN(n) ((n) << 3) + +/* setup register */ +#define MAX1027_UNIPOLAR 0x02 +#define MAX1027_BIPOLAR 0x03 +#define MAX1027_REF_MODE0 (0x00 << 2) +#define MAX1027_REF_MODE1 (0x01 << 2) +#define MAX1027_REF_MODE2 (0x02 << 2) +#define MAX1027_REF_MODE3 (0x03 << 2) +#define MAX1027_CKS_MODE0 (0x00 << 4) +#define MAX1027_CKS_MODE1 (0x01 << 4) +#define MAX1027_CKS_MODE2 (0x02 << 4) +#define MAX1027_CKS_MODE3 (0x03 << 4) + +/* averaging register */ +#define MAX1027_NSCAN_4 0x00 +#define MAX1027_NSCAN_8 0x01 +#define MAX1027_NSCAN_12 0x02 +#define MAX1027_NSCAN_16 0x03 +#define MAX1027_NAVG_4 (0x00 << 2) +#define MAX1027_NAVG_8 (0x01 << 2) +#define MAX1027_NAVG_16 (0x02 << 2) +#define MAX1027_NAVG_32 (0x03 << 2) +#define MAX1027_AVG_EN BIT(4) + +enum max1027_id { + max1027, + max1029, + max1031, +}; + +static const struct spi_device_id max1027_id[] = { + {"max1027", max1027}, + {"max1029", max1029}, + {"max1031", max1031}, + {} +}; +MODULE_DEVICE_TABLE(spi, max1027_id); + +#ifdef CONFIG_OF +static const struct of_device_id max1027_adc_dt_ids[] = { + { .compatible = "maxim,max1027" }, + { .compatible = "maxim,max1029" }, + { .compatible = "maxim,max1031" }, + {}, +}; +MODULE_DEVICE_TABLE(of, max1027_adc_dt_ids); +#endif + +#define MAX1027_V_CHAN(index) \ + { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .channel = index, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ + .scan_index = index + 1, \ + .scan_type = { \ + .sign = 'u', \ + .realbits = 10, \ + .storagebits = 16, \ + .shift = 2, \ + .endianness = IIO_BE, \ + }, \ + } + +#define MAX1027_T_CHAN \ + { \ + .type = IIO_TEMP, \ + .channel = 0, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ + .scan_index = 0, \ + .scan_type = { \ + .sign = 'u', \ + .realbits = 12, \ + .storagebits = 16, \ + .endianness = IIO_BE, \ + }, \ + } + +static const struct iio_chan_spec max1027_channels[] = { + MAX1027_T_CHAN, + MAX1027_V_CHAN(0), + MAX1027_V_CHAN(1), + MAX1027_V_CHAN(2), + MAX1027_V_CHAN(3), + MAX1027_V_CHAN(4), + MAX1027_V_CHAN(5), + MAX1027_V_CHAN(6), + MAX1027_V_CHAN(7) +}; + +static const struct iio_chan_spec max1029_channels[] = { + MAX1027_T_CHAN, + MAX1027_V_CHAN(0), + MAX1027_V_CHAN(1), + MAX1027_V_CHAN(2), + MAX1027_V_CHAN(3), + MAX1027_V_CHAN(4), + MAX1027_V_CHAN(5), + MAX1027_V_CHAN(6), + MAX1027_V_CHAN(7), + MAX1027_V_CHAN(8), + MAX1027_V_CHAN(9), + MAX1027_V_CHAN(10), + MAX1027_V_CHAN(11) +}; + +static const struct iio_chan_spec max1031_channels[] = { + MAX1027_T_CHAN, + MAX1027_V_CHAN(0), + MAX1027_V_CHAN(1), + MAX1027_V_CHAN(2), + MAX1027_V_CHAN(3), + MAX1027_V_CHAN(4), + MAX1027_V_CHAN(5), + MAX1027_V_CHAN(6), + MAX1027_V_CHAN(7), + MAX1027_V_CHAN(8), + MAX1027_V_CHAN(9), + MAX1027_V_CHAN(10), + MAX1027_V_CHAN(11), + MAX1027_V_CHAN(12), + MAX1027_V_CHAN(13), + MAX1027_V_CHAN(14), + MAX1027_V_CHAN(15) +}; + +static const unsigned long max1027_available_scan_masks[] = { + 0x000001ff, + 0x00000000, +}; + +static const unsigned long max1029_available_scan_masks[] = { + 0x00001fff, + 0x00000000, +}; + +static const unsigned long max1031_available_scan_masks[] = { + 0x0001ffff, + 0x00000000, +}; + +struct max1027_chip_info { + const struct iio_chan_spec *channels; + unsigned int num_channels; + const unsigned long *available_scan_masks; +}; + +static const struct max1027_chip_info max1027_chip_info_tbl[] = { + [max1027] = { + .channels = max1027_channels, + .num_channels = ARRAY_SIZE(max1027_channels), + .available_scan_masks = max1027_available_scan_masks, + }, + [max1029] = { + .channels = max1029_channels, + .num_channels = ARRAY_SIZE(max1029_channels), + .available_scan_masks = max1029_available_scan_masks, + }, + [max1031] = { + .channels = max1031_channels, + .num_channels = ARRAY_SIZE(max1031_channels), + .available_scan_masks = max1031_available_scan_masks, + }, +}; + +struct max1027_state { + const struct max1027_chip_info *info; + struct spi_device *spi; + struct iio_trigger *trig; + __be16 *buffer; + struct mutex lock; + + u8 reg ____cacheline_aligned; +}; + +static int max1027_read_single_value(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val) +{ + int ret; + struct max1027_state *st = iio_priv(indio_dev); + + if (iio_buffer_enabled(indio_dev)) { + dev_warn(&indio_dev->dev, "trigger mode already enabled"); + return -EBUSY; + } + + /* Start acquisition on conversion register write */ + st->reg = MAX1027_SETUP_REG | MAX1027_REF_MODE2 | MAX1027_CKS_MODE2; + ret = spi_write(st->spi, &st->reg, 1); + if (ret < 0) { + dev_err(&indio_dev->dev, + "Failed to configure setup register\n"); + return ret; + } + + /* Configure conversion register with the requested chan */ + st->reg = MAX1027_CONV_REG | MAX1027_CHAN(chan->channel) | + MAX1027_NOSCAN | !!(chan->type == IIO_TEMP); + ret = spi_write(st->spi, &st->reg, 1); + if (ret < 0) { + dev_err(&indio_dev->dev, + "Failed to configure conversion register\n"); + return ret; + } + + /* + * For an unknown reason, when we use the mode "10" (write + * conversion register), the interrupt doesn't occur every time. + * So we just wait 1 ms. + */ + mdelay(1); + + /* Read result */ + ret = spi_read(st->spi, st->buffer, (chan->type == IIO_TEMP) ? 4 : 2); + if (ret < 0) + return ret; + + *val = be16_to_cpu(st->buffer[0]); + + return IIO_VAL_INT; +} + +static int max1027_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + int ret = 0; + struct max1027_state *st = iio_priv(indio_dev); + + mutex_lock(&st->lock); + + switch (mask) { + case IIO_CHAN_INFO_RAW: + ret = max1027_read_single_value(indio_dev, chan, val); + break; + case IIO_CHAN_INFO_SCALE: + switch (chan->type) { + case IIO_TEMP: + *val = 1; + *val2 = 8; + ret = IIO_VAL_FRACTIONAL; + break; + case IIO_VOLTAGE: + *val = 2500; + *val2 = 10; + ret = IIO_VAL_FRACTIONAL_LOG2; + break; + default: + ret = -EINVAL; + break; + } + break; + default: + ret = -EINVAL; + break; + } + + mutex_unlock(&st->lock); + + return ret; +} + +static int max1027_debugfs_reg_access(struct iio_dev *indio_dev, + unsigned reg, unsigned writeval, + unsigned *readval) +{ + struct max1027_state *st = iio_priv(indio_dev); + u8 *val = (u8 *)st->buffer; + + if (readval != NULL) + return -EINVAL; + + *val = (u8)writeval; + return spi_write(st->spi, val, 1); +} + +static int max1027_validate_trigger(struct iio_dev *indio_dev, + struct iio_trigger *trig) +{ + struct max1027_state *st = iio_priv(indio_dev); + + if (st->trig != trig) + return -EINVAL; + + return 0; +} + +static int max1027_set_trigger_state(struct iio_trigger *trig, bool state) +{ + struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig); + struct max1027_state *st = iio_priv(indio_dev); + int ret; + + if (state) { + /* Start acquisition on cnvst */ + st->reg = MAX1027_SETUP_REG | MAX1027_CKS_MODE0 | + MAX1027_REF_MODE2; + ret = spi_write(st->spi, &st->reg, 1); + if (ret < 0) + return ret; + + /* Scan from 0 to max */ + st->reg = MAX1027_CONV_REG | MAX1027_CHAN(0) | + MAX1027_SCAN_N_M | MAX1027_TEMP; + ret = spi_write(st->spi, &st->reg, 1); + if (ret < 0) + return ret; + } else { + /* Start acquisition on conversion register write */ + st->reg = MAX1027_SETUP_REG | MAX1027_CKS_MODE2 | + MAX1027_REF_MODE2; + ret = spi_write(st->spi, &st->reg, 1); + if (ret < 0) + return ret; + } + + return 0; +} + +static int max1027_validate_device(struct iio_trigger *trig, + struct iio_dev *indio_dev) +{ + struct iio_dev *indio = iio_trigger_get_drvdata(trig); + + if (indio != indio_dev) + return -EINVAL; + + return 0; +} + +static irqreturn_t max1027_trigger_handler(int irq, void *private) +{ + struct iio_poll_func *pf = (struct iio_poll_func *)private; + struct iio_dev *indio_dev = pf->indio_dev; + struct max1027_state *st = iio_priv(indio_dev); + + pr_debug("%s(irq=%d, private=0x%p)\n", __func__, irq, private); + + /* fill buffer with all channel */ + spi_read(st->spi, st->buffer, indio_dev->masklength * 2); + + iio_push_to_buffers(indio_dev, st->buffer); + + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +static const struct iio_trigger_ops max1027_trigger_ops = { + .owner = THIS_MODULE, + .validate_device = &max1027_validate_device, + .set_trigger_state = &max1027_set_trigger_state, +}; + +static const struct iio_info max1027_info = { + .driver_module = THIS_MODULE, + .read_raw = &max1027_read_raw, + .validate_trigger = &max1027_validate_trigger, + .debugfs_reg_access = &max1027_debugfs_reg_access, +}; + +static int max1027_probe(struct spi_device *spi) +{ + int ret; + struct iio_dev *indio_dev; + struct max1027_state *st; + + pr_debug("%s: probe(spi = 0x%p)\n", __func__, spi); + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); + if (indio_dev == NULL) { + pr_err("Can't allocate iio device\n"); + return -ENOMEM; + } + + spi_set_drvdata(spi, indio_dev); + + st = iio_priv(indio_dev); + st->spi = spi; + st->info = &max1027_chip_info_tbl[spi_get_device_id(spi)->driver_data]; + + mutex_init(&st->lock); + + indio_dev->name = spi_get_device_id(spi)->name; + indio_dev->dev.parent = &spi->dev; + indio_dev->info = &max1027_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = st->info->channels; + indio_dev->num_channels = st->info->num_channels; + indio_dev->available_scan_masks = st->info->available_scan_masks; + + st->buffer = devm_kmalloc(&indio_dev->dev, + indio_dev->num_channels * 2, + GFP_KERNEL); + if (st->buffer == NULL) { + dev_err(&indio_dev->dev, "Can't allocate bufffer\n"); + return -ENOMEM; + } + + ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time, + &max1027_trigger_handler, NULL); + if (ret < 0) { + dev_err(&indio_dev->dev, "Failed to setup buffer\n"); + return ret; + } + + st->trig = devm_iio_trigger_alloc(&spi->dev, "%s-trigger", + indio_dev->name); + if (st->trig == NULL) { + ret = -ENOMEM; + dev_err(&indio_dev->dev, "Failed to allocate iio trigger\n"); + goto fail_trigger_alloc; + } + + st->trig->ops = &max1027_trigger_ops; + st->trig->dev.parent = &spi->dev; + iio_trigger_set_drvdata(st->trig, indio_dev); + iio_trigger_register(st->trig); + + ret = devm_request_threaded_irq(&spi->dev, spi->irq, + iio_trigger_generic_data_rdy_poll, + NULL, + IRQF_TRIGGER_FALLING, + spi->dev.driver->name, st->trig); + if (ret < 0) { + dev_err(&indio_dev->dev, "Failed to allocate IRQ.\n"); + goto fail_dev_register; + } + + /* Disable averaging */ + st->reg = MAX1027_AVG_REG; + ret = spi_write(st->spi, &st->reg, 1); + if (ret < 0) { + dev_err(&indio_dev->dev, "Failed to configure averaging register\n"); + goto fail_dev_register; + } + + ret = iio_device_register(indio_dev); + if (ret < 0) { + dev_err(&indio_dev->dev, "Failed to register iio device\n"); + goto fail_dev_register; + } + + return 0; + +fail_dev_register: +fail_trigger_alloc: + iio_triggered_buffer_cleanup(indio_dev); + + return ret; +} + +static int max1027_remove(struct spi_device *spi) +{ + struct iio_dev *indio_dev = spi_get_drvdata(spi); + + pr_debug("%s: remove(spi = 0x%p)\n", __func__, spi); + + iio_device_unregister(indio_dev); + iio_triggered_buffer_cleanup(indio_dev); + + return 0; +} + +static struct spi_driver max1027_driver = { + .driver = { + .name = "max1027", + .owner = THIS_MODULE, + }, + .probe = max1027_probe, + .remove = max1027_remove, + .id_table = max1027_id, +}; +module_spi_driver(max1027_driver); + +MODULE_AUTHOR("Philippe Reynes <tremyfr@yahoo.fr>"); +MODULE_DESCRIPTION("MAX1027/MAX1029/MAX1031 ADC"); +MODULE_LICENSE("GPL v2"); |