Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932386AbbHCU5P (ORCPT ); Mon, 3 Aug 2015 16:57:15 -0400 Received: from mail-io0-f179.google.com ([209.85.223.179]:33514 "EHLO mail-io0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755535AbbHCU5I (ORCPT ); Mon, 3 Aug 2015 16:57:08 -0400 From: Matt Porter To: Linux IIO List , Devicetree List Cc: Jonathan Cameron , Rob Herring , Mark Rutland , Linux Kernel Mailing List Subject: [PATCH 2/3] iio: temperature: add max6675 thermocouple converter driver Date: Mon, 3 Aug 2015 16:56:49 -0400 Message-Id: <1438635410-3757-3-git-send-email-mporter@konsulko.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1438635410-3757-1-git-send-email-mporter@konsulko.com> References: <1438635410-3757-1-git-send-email-mporter@konsulko.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5632 Lines: 215 Add a driver for the MAX6675 thermocouple converter. This device interfaces with K-type thermocouples and provides cold-junction compensated temperature readings via a SPI interface. Signed-off-by: Matt Porter --- drivers/iio/temperature/Kconfig | 11 +++ drivers/iio/temperature/Makefile | 1 + drivers/iio/temperature/max6675.c | 155 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 167 insertions(+) create mode 100644 drivers/iio/temperature/max6675.c diff --git a/drivers/iio/temperature/Kconfig b/drivers/iio/temperature/Kconfig index 21feaa4..b73fbf4 100644 --- a/drivers/iio/temperature/Kconfig +++ b/drivers/iio/temperature/Kconfig @@ -3,6 +3,17 @@ # menu "Temperature sensors" +config MAX6675 + tristate "MAX6675 thermocouple converter" + depends on SPI + help + If you say yes here you get support for the Maxim + MAX6675 thermocouple converter connected with SPI. + + This driver can also be built as a module. If so, the module will + be called max6675. + + config MLX90614 tristate "MLX90614 contact-less infrared sensor" depends on I2C diff --git a/drivers/iio/temperature/Makefile b/drivers/iio/temperature/Makefile index 40710a8..d67ef40 100644 --- a/drivers/iio/temperature/Makefile +++ b/drivers/iio/temperature/Makefile @@ -2,5 +2,6 @@ # Makefile for industrial I/O temperature drivers # +obj-$(CONFIG_MAX6675) += max6675.o obj-$(CONFIG_MLX90614) += mlx90614.o obj-$(CONFIG_TMP006) += tmp006.o diff --git a/drivers/iio/temperature/max6675.c b/drivers/iio/temperature/max6675.c new file mode 100644 index 0000000..2d1fda2 --- /dev/null +++ b/drivers/iio/temperature/max6675.c @@ -0,0 +1,155 @@ +/* + * max6675.c - MAX6675 thermocouple converter driver + * + * Copyright (C) 2015 Konsulko Group, Matt Porter + * + * 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 +#include +#include +#include +#include +#include + +struct max6675_state { + struct spi_device *spi; +}; + +static const struct iio_chan_spec max6675_channels[] = { + { + .type = IIO_TEMP, + .info_mask_separate = + BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE), + }, +}; + +static int max6675_read(struct max6675_state *st, int *val) +{ + int ret; + + ret = spi_read(st->spi, val, 2); + if (ret < 0) + return ret; + + /* Temperature is bits 14..3 */ + *val = (*val >> 3) & 0xfff; + + return ret; +} + +static int max6675_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2, + long m) +{ + struct max6675_state *st = iio_priv(indio_dev); + int ret; + + if (m == IIO_CHAN_INFO_RAW) { + *val2 = 0; + ret = max6675_read(st, val); + if (ret) + return ret; + } else if (m == IIO_CHAN_INFO_SCALE) { + *val = 250; + *val2 = 0; + } else + return -EINVAL; + + return IIO_VAL_INT; +} + +static const struct iio_info max6675_info = { + .driver_module = THIS_MODULE, + .read_raw = &max6675_read_raw, +}; + +static int max6675_probe(struct spi_device *spi) +{ + struct iio_dev *indio_dev; + struct max6675_state *st; + int ret = 0; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + st->spi = spi; + + spi->mode = SPI_MODE_1; + spi->bits_per_word = 16; + + spi_set_drvdata(spi, indio_dev); + + indio_dev->dev.parent = &spi->dev; + indio_dev->name = spi_get_device_id(spi)->name; + indio_dev->channels = max6675_channels; + indio_dev->num_channels = ARRAY_SIZE(max6675_channels); + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &max6675_info; + + ret = iio_device_register(indio_dev); + if (ret < 0) + dev_err(&spi->dev, "unable to register device\n"); + + return ret; +} + +static int max6675_remove(struct spi_device *spi) +{ + struct iio_dev *indio_dev = spi_get_drvdata(spi); + + iio_device_unregister(indio_dev); + + return 0; +} + +static const struct acpi_device_id max6675_acpi_ids[] = { + { "MXIM6675", 0 }, + {}, +}; +MODULE_DEVICE_TABLE(acpi, max6675_acpi_ids); + +static const struct of_device_id max6675_dt_ids[] = { + { .compatible = "maxim,max6675" }, + {}, +}; +MODULE_DEVICE_TABLE(of, max6675_dt_ids); + +static const struct spi_device_id max6675_spi_ids[] = { + {"max6675", 0}, + {}, +}; +MODULE_DEVICE_TABLE(spi, max6675_spi_ids); + +static struct spi_driver max6675_driver = { + .driver = { + .name = "max6675", + .owner = THIS_MODULE, + .acpi_match_table = ACPI_PTR(max6675_acpi_ids), + .of_match_table = of_match_ptr(max6675_dt_ids), + }, + .probe = max6675_probe, + .remove = max6675_remove, + .id_table = max6675_spi_ids, +}; +module_spi_driver(max6675_driver); + +MODULE_AUTHOR("Matt Porter "); +MODULE_DESCRIPTION("MAX6675 thermocouple converter driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("spi:max6675"); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/