From: Abhisit Sangjan <s.abhisit@xxxxxxxxx> --- drivers/iio/adc/Kconfig | 10 + drivers/iio/adc/Makefile | 1 + drivers/iio/adc/lmp92001-adc.c | 479 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 490 insertions(+) create mode 100644 drivers/iio/adc/lmp92001-adc.c diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 614fa41..b623b4d 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -857,4 +857,14 @@ config XILINX_XADC The driver can also be build as a module. If so, the module will be called xilinx-xadc. +config LMP92001_ADC + tristate "TI LMP92001 ADC Driver" + depends on MFD_LMP92001 + help + If you say yes here you get support for TI LMP92001 ADCs + conversion. + + This driver can also be built as a module. If so, the module will + be called lmp92001_adc. + endmenu diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index b546736a..75b24b1 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -78,3 +78,4 @@ obj-$(CONFIG_VF610_ADC) += vf610_adc.o obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o xilinx-xadc-y := xilinx-xadc-core.o xilinx-xadc-events.o obj-$(CONFIG_XILINX_XADC) += xilinx-xadc.o +obj-$(CONFIG_LMP92001_ADC) += lmp92001-adc.o diff --git a/drivers/iio/adc/lmp92001-adc.c b/drivers/iio/adc/lmp92001-adc.c new file mode 100644 index 0000000..909ff47 --- /dev/null +++ b/drivers/iio/adc/lmp92001-adc.c @@ -0,0 +1,479 @@ +/* + * lmp92001-adc.c - Support for TI LMP92001 ADCs + * + * Copyright 2016-2017 Celestica Ltd. + * + * Author: Abhisit Sangjan <s.abhisit@xxxxxxxxx> + * + * Inspired by wm831x and ad5064 drivers. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * 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/kernel.h> +#include <linux/module.h> +#include <linux/iio/iio.h> +#include <linux/mfd/core.h> +#include <linux/platform_device.h> +#include <linux/interrupt.h> + +#include <linux/mfd/lmp92001/core.h> + +static int lmp92001_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *channel, int *val, + int *val2, long mask) +{ + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev); + unsigned int code, cgen, sgen, try; + int ret; + + ret = regmap_read(lmp92001->regmap, LMP92001_CGEN, &cgen); + if (ret < 0) + return ret; + + /* + * Is not continuous conversion? + * Lock the registers (if needed). + * Triggering single-short conversion. + * Waiting for conversion successfully. + */ + if (!(cgen & 1)) + { + if (!(cgen & 2)) + { + ret = regmap_update_bits(lmp92001->regmap, + LMP92001_CGEN, 2, 2); + if (ret < 0) + return ret; + } + + ret = regmap_write(lmp92001->regmap, LMP92001_CTRIG, 1); + if (ret < 0) + return ret; + + try = 10; + do { + ret = regmap_read(lmp92001->regmap, + LMP92001_SGEN, &sgen); + if(ret < 0) + return ret; + } while ((sgen & 1<<7) && (--try > 0)); + + if (!try) + return -ETIME; + } + + ret = regmap_read(lmp92001->regmap, 0x1F + channel->channel, &code); + if (ret < 0) + return ret; + + switch (mask) + { + case IIO_CHAN_INFO_RAW: + switch (channel->type) { + case IIO_VOLTAGE: + case IIO_TEMP: + *val = code; + return IIO_VAL_INT; + default: + break; + } + break; + default: + break; + } + + return -EINVAL; +} + +/* + * TODO: do your attributes even handler for + * Current limit low/high for CH 1-3, 9-11! + * In case INT1 and INT2 were connected to i.MX6. + */ +static const struct iio_info lmp92001_info = { + .read_raw = lmp92001_read_raw, + .driver_module = THIS_MODULE, +}; + +static ssize_t lmp92001_avref_read(struct iio_dev *indio_dev, uintptr_t private, + struct iio_chan_spec const *channel, char *buf) +{ + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev); + unsigned int cref; + int ret; + + ret = regmap_read(lmp92001->regmap, LMP92001_CREF, &cref); + if (ret < 0) + return ret; + + return sprintf(buf, "%s\n", cref & 2 ? "external" : "internal"); +} + +static ssize_t lmp92001_avref_write(struct iio_dev *indio_dev, uintptr_t private, + struct iio_chan_spec const *channel, const char *buf, + size_t len) +{ + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev); + unsigned int cref; + int ret; + + if (strcmp("external\n", buf) == 0) + cref = 2; + else if (strcmp("internal\n", buf) == 0) + cref = 0; + else + return -EINVAL; + + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CREF, 2, cref); + if (ret < 0) + return ret; + + return len; +} + +static ssize_t lmp92001_enable_read(struct iio_dev *indio_dev, uintptr_t private, + struct iio_chan_spec const *channel, char *buf) +{ + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev); + unsigned int reg, cad; + int ret; + + switch (channel->channel) + { + case 1 ... 8: + reg = LMP92001_CAD1; + break; + case 9 ... 16: + reg = LMP92001_CAD2; + break; + case 17: + reg = LMP92001_CAD3; + break; + default: + return -EINVAL; + } + + ret = regmap_read(lmp92001->regmap, reg, &cad); + if (ret < 0) + return ret; + + if (channel->channel <= 8) + cad >>= channel->channel - 1; + else if(channel->channel > 8) + cad >>= channel->channel - 9; + else if(channel->channel > 16) + cad >>= channel->channel - 17; + else + return -EINVAL; + + return sprintf(buf, "%s\n", cad & 1 ? "enable" : "disable"); +} + +static ssize_t lmp92001_enable_write(struct iio_dev *indio_dev, uintptr_t private, + struct iio_chan_spec const *channel, const char *buf, + size_t len) +{ + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev); + unsigned int reg, enable, shif, mask; + int ret; + + switch (channel->channel) + { + case 1 ... 8: + reg = LMP92001_CAD1; + shif = (channel->channel - 1); + break; + case 9 ... 16: + reg = LMP92001_CAD2; + shif = (channel->channel - 9); + break; + case 17: + reg = LMP92001_CAD3; + shif = (channel->channel - 17); + break; + default: + return -EINVAL; + } + + if (strcmp("enable\n", buf) == 0) + enable = 1; + else if (strcmp("disable\n", buf) == 0) + enable = 0; + else + return -EINVAL; + + enable <<= shif; + mask = 1 << shif; + + ret = regmap_update_bits(lmp92001->regmap, reg, mask, enable); + if (ret < 0) + return ret; + + return len; +} + +static ssize_t lmp92001_mode_read(struct iio_dev *indio_dev, uintptr_t private, + struct iio_chan_spec const *channel, char *buf) +{ + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev); + unsigned int cgen; + int ret; + + ret = regmap_read(lmp92001->regmap, LMP92001_CGEN, &cgen); + if (ret < 0) + return ret; + + return sprintf(buf, "%s\n", cgen & 1 ? "continuous" : "single-shot"); +} + +static ssize_t lmp92001_mode_write(struct iio_dev *indio_dev, uintptr_t private, + struct iio_chan_spec const *channel, const char *buf, + size_t len) +{ + struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev); + unsigned int cgen; + int ret; + + if (strcmp("continuous\n", buf) == 0) + cgen = 1; + else if (strcmp("single-shot\n", buf) == 0) + cgen = 0; + else + return -EINVAL; + + /* + * Unlock the registers. + * Set conversion mode. + * Lock the registers. + */ + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, 2, 0); + if (ret < 0) + return ret; + + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, 1, cgen); + if (ret < 0) + return ret; + + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, 2, 2); + if (ret < 0) + return ret; + + return len; +} + +static const struct iio_chan_spec_ext_info lmp92001_ext_info[] = { + { + .name = "vref", + .read = lmp92001_avref_read, + .write = lmp92001_avref_write, + .shared = IIO_SHARED_BY_ALL, + }, + { + .name = "en", + .read = lmp92001_enable_read, + .write = lmp92001_enable_write, + .shared = IIO_SEPARATE, + }, + { + .name = "mode", + .read = lmp92001_mode_read, + .write = lmp92001_mode_write, + .shared = IIO_SHARED_BY_ALL, + }, + { }, +}; + +static const struct iio_event_spec lmp92001_events[] = { + { + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_RISING, + .mask_separate = BIT(IIO_EV_INFO_ENABLE) | + BIT(IIO_EV_INFO_VALUE), + }, + { + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_FALLING, + .mask_separate = BIT(IIO_EV_INFO_ENABLE) | + BIT(IIO_EV_INFO_VALUE), + }, + { }, +}; + +#define LMP92001_CHAN_SPEC(_ch, _type, _event, _nevent) \ +{ \ + .channel = _ch, \ + .scan_index = _ch, \ + .scan_type = { \ + .sign = 'u', \ + .realbits = 12, \ + .storagebits = 16, \ + .repeat = 1, \ + .endianness = IIO_BE, \ + }, \ + .type = _type, \ + .indexed = 1, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .event_spec = _event, \ + .num_event_specs = _nevent, \ + .ext_info = lmp92001_ext_info, \ +} + +/* + * TODO: do your ext_info for current low/high limit. + * Example driver/iio/dac/ad5064.c + */ +static const struct iio_chan_spec lmp92001_adc_channels[] = { + LMP92001_CHAN_SPEC( 1, IIO_VOLTAGE, lmp92001_events, ARRAY_SIZE(lmp92001_events)), + LMP92001_CHAN_SPEC( 2, IIO_VOLTAGE, lmp92001_events, ARRAY_SIZE(lmp92001_events)), + LMP92001_CHAN_SPEC( 3, IIO_VOLTAGE, lmp92001_events, ARRAY_SIZE(lmp92001_events)), + LMP92001_CHAN_SPEC( 4, IIO_VOLTAGE, NULL, 0), + LMP92001_CHAN_SPEC( 5, IIO_VOLTAGE, NULL, 0), + LMP92001_CHAN_SPEC( 6, IIO_VOLTAGE, NULL, 0), + LMP92001_CHAN_SPEC( 7, IIO_VOLTAGE, NULL, 0), + LMP92001_CHAN_SPEC( 8, IIO_VOLTAGE, NULL, 0), + LMP92001_CHAN_SPEC( 9, IIO_VOLTAGE, lmp92001_events, ARRAY_SIZE(lmp92001_events)), + LMP92001_CHAN_SPEC(10, IIO_VOLTAGE, lmp92001_events, ARRAY_SIZE(lmp92001_events)), + LMP92001_CHAN_SPEC(11, IIO_VOLTAGE, lmp92001_events, ARRAY_SIZE(lmp92001_events)), + LMP92001_CHAN_SPEC(12, IIO_VOLTAGE, NULL, 0), + LMP92001_CHAN_SPEC(13, IIO_VOLTAGE, NULL, 0), + LMP92001_CHAN_SPEC(14, IIO_VOLTAGE, NULL, 0), + LMP92001_CHAN_SPEC(15, IIO_VOLTAGE, NULL, 0), + LMP92001_CHAN_SPEC(16, IIO_VOLTAGE, NULL, 0), + LMP92001_CHAN_SPEC(17, IIO_TEMP, NULL, 0), +}; + +static int lmp92001_adc_probe(struct platform_device *pdev) +{ + struct lmp92001 *lmp92001 = dev_get_drvdata(pdev->dev.parent); + struct iio_dev *indio_dev; + struct device_node *np = pdev->dev.of_node; + const char *conversion; + unsigned int cgen = 0, cad1, cad2, cad3; + u32 mask; + int ret; + + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*lmp92001)); + if (!indio_dev) + return -ENOMEM; + + iio_device_set_drvdata(indio_dev, lmp92001); + + indio_dev->name = pdev->name; + indio_dev->dev.parent = &pdev->dev; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &lmp92001_info; + indio_dev->channels = lmp92001_adc_channels; + indio_dev->num_channels = ARRAY_SIZE(lmp92001_adc_channels); + + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, 0x80, 0x80); + if (ret < 0) + { + dev_err(&pdev->dev,"failed to self reset all registers\n"); + return ret; + } + + ret = of_property_read_u32(np, "ti,lmp92001-adc-mask", &mask); + if (ret < 0) + { + cad1 = cad2 = cad3 = 0xFF; + dev_info(&pdev->dev, "turn on all of channels by default\n"); + } + else + { + cad1 = mask & 0xFF; + cad2 = (mask >> 8) & 0xFF; + cad3 = (mask >> 16) & 0xFF; + } + + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CAD1, 0xFF, cad1); + if (ret < 0) + { + dev_err(&pdev->dev,"failed to enable channels 1-8\n"); + return ret; + } + + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CAD2, 0xFF, cad2); + if (ret < 0) + { + dev_err(&pdev->dev, "failed to enable channels 9-16\n"); + return ret; + } + + ret = regmap_update_bits(lmp92001->regmap, LMP92001_CAD3, 1, cad3); + if (ret < 0) + { + dev_err(&pdev->dev, "failed to enable channel 17 (temperature)\n"); + return ret; + } + + ret = of_property_read_string_index(np, "ti,lmp92001-adc-mode", 0, + &conversion); + if (!ret) + { + if (strcmp("continuous", conversion) == 0) + cgen |= 1; + else if (strcmp("single-shot", conversion) == 0) + { /* Okay */ } + else + dev_warn(&pdev->dev, + "wrong adc mode! set to single-short conversion\n"); + } + else + dev_info(&pdev->dev, + "single-short conversion was chosen by default\n"); + + /* + * Lock the registers and set conversion mode. + */ + ret = regmap_update_bits(lmp92001->regmap, + LMP92001_CGEN, 3, cgen | 2); + if (ret < 0) + return ret; + + platform_set_drvdata(pdev, indio_dev); + + return iio_device_register(indio_dev); +} + +static int lmp92001_adc_remove(struct platform_device *pdev) +{ + struct iio_dev *indio_dev = platform_get_drvdata(pdev); + + iio_device_unregister(indio_dev); + + return 0; +} + +static struct platform_driver lmp92001_adc_driver = { + .driver.name = "lmp92001-adc", + .driver.owner = THIS_MODULE, + .probe = lmp92001_adc_probe, + .remove = lmp92001_adc_remove, +}; + +static int __init lmp92001_adc_init(void) +{ + return platform_driver_register(&lmp92001_adc_driver); +} +subsys_initcall(lmp92001_adc_init); + +static void __exit lmp92001_adc_exit(void) +{ + platform_driver_unregister(&lmp92001_adc_driver); +} +module_exit(lmp92001_adc_exit); + +MODULE_AUTHOR("Abhisit Sangjan <s.abhisit@xxxxxxxxx>"); +MODULE_DESCRIPTION("IIO ADC interface for TI LMP92001"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:lmp92001-adc"); -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html