From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Mike Frysinger To: linux-iio@vger.kernel.org, Jonathan Cameron Cc: device-drivers-devel@blackfin.uclinux.org, Sonic Zhang Subject: [PATCH 03/14] staging: iio: adc: new driver for AD7298 devices Date: Sat, 23 Oct 2010 16:29:06 -0400 Message-Id: <1287865757-1031-3-git-send-email-vapier@gentoo.org> In-Reply-To: <1287865757-1031-1-git-send-email-vapier@gentoo.org> References: <1287865757-1031-1-git-send-email-vapier@gentoo.org> List-ID: From: Sonic Zhang Signed-off-by: Sonic Zhang Signed-off-by: Mike Frysinger --- drivers/staging/iio/adc/Kconfig | 7 + drivers/staging/iio/adc/Makefile | 1 + drivers/staging/iio/adc/ad7298.c | 501 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 509 insertions(+), 0 deletions(-) create mode 100644 drivers/staging/iio/adc/ad7298.c diff --git a/drivers/staging/iio/adc/Kconfig b/drivers/staging/iio/adc/Kconfig index a4c41dc..847f5f2 100644 --- a/drivers/staging/iio/adc/Kconfig +++ b/drivers/staging/iio/adc/Kconfig @@ -47,3 +47,10 @@ config AD7291 help Say yes here to build support for Analog Devices AD7291 temperature sensors. + +config AD7298 + tristate "Analog Devices AD7298 temperature sensor and ADC driver" + depends on SPI + help + Say yes here to build support for Analog Devices AD7298 + temperature sensors and ADC. diff --git a/drivers/staging/iio/adc/Makefile b/drivers/staging/iio/adc/Makefile index 7d8ac9a..d0ea747 100644 --- a/drivers/staging/iio/adc/Makefile +++ b/drivers/staging/iio/adc/Makefile @@ -9,3 +9,4 @@ obj-$(CONFIG_MAX1363) += max1363.o obj-$(CONFIG_AD7150) += ad7150.o obj-$(CONFIG_AD7152) += ad7152.o obj-$(CONFIG_AD7291) += ad7291.o +obj-$(CONFIG_AD7298) += ad7298.o diff --git a/drivers/staging/iio/adc/ad7298.c b/drivers/staging/iio/adc/ad7298.c new file mode 100644 index 0000000..1a080c9 --- /dev/null +++ b/drivers/staging/iio/adc/ad7298.c @@ -0,0 +1,501 @@ +/* + * AD7298 digital temperature sensor driver supporting AD7298 + * + * Copyright 2010 Analog Devices Inc. + * + * Licensed under the GPL-2 or later. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../iio.h" +#include "../sysfs.h" + +/* + * AD7298 command + */ +#define AD7298_PD 0x1 +#define AD7298_T_AVG_MASK 0x2 +#define AD7298_EXT_REF 0x4 +#define AD7298_T_SENSE_MASK 0x20 +#define AD7298_VOLTAGE_MASK 0x3fc0 +#define AD7298_VOLTAGE_OFFSET 0x6 +#define AD7298_VOLTAGE_LIMIT_COUNT 8 +#define AD7298_REPEAT 0x40 +#define AD7298_WRITE 0x80 + +/* + * AD7298 value masks + */ +#define AD7298_CHANNEL_MASK 0xf000 +#define AD7298_VALUE_MASK 0xfff +#define AD7298_T_VALUE_SIGN 0x400 +#define AD7298_T_VALUE_FLOAT_OFFSET 2 +#define AD7298_T_VALUE_FLOAT_MASK 0x2 + +/* + * struct ad7298_chip_info - chip specifc information + */ + +struct ad7298_chip_info { + const char *name; + struct spi_device *spi_dev; + struct iio_dev *indio_dev; + u16 command; + u16 busy_pin; + u8 channels; /* Active voltage channels */ +}; + +/* + * ad7298 register access by SPI + */ +static int ad7298_spi_write(struct ad7298_chip_info *chip, u16 data) +{ + struct spi_device *spi_dev = chip->spi_dev; + int ret = 0; + + data |= AD7298_WRITE; + data = cpu_to_be16(data); + ret = spi_write(spi_dev, (u8 *)&data, sizeof(data)); + if (ret < 0) + dev_err(&spi_dev->dev, "SPI write error\n"); + + return ret; +} + +static int ad7298_spi_read(struct ad7298_chip_info *chip, u16 mask, u16 *data) +{ + struct spi_device *spi_dev = chip->spi_dev; + int ret = 0; + u8 count = chip->channels; + u16 command; + int i; + + if (mask & AD7298_T_SENSE_MASK) { + command = chip->command & ~(AD7298_T_AVG_MASK | AD7298_VOLTAGE_MASK); + command |= AD7298_T_SENSE_MASK; + count = 1; + } else if (mask & AD7298_T_AVG_MASK) { + command = chip->command & ~AD7298_VOLTAGE_MASK; + command |= AD7298_T_SENSE_MASK | AD7298_T_AVG_MASK; + count = 2; + } else if (mask & AD7298_VOLTAGE_MASK) { + command = chip->command & ~(AD7298_T_AVG_MASK | AD7298_T_SENSE_MASK); + count = chip->channels; + } + + ret = ad7298_spi_write(chip, chip->command); + if (ret < 0) { + dev_err(&spi_dev->dev, "SPI write command error\n"); + return ret; + } + + ret = spi_read(spi_dev, (u8 *)&command, sizeof(command)); + if (ret < 0) { + dev_err(&spi_dev->dev, "SPI read error\n"); + return ret; + } + + i = 10000; + while (i && gpio_get_value(chip->busy_pin)) { + cpu_relax(); + i--; + } + if (!i) { + dev_err(&spi_dev->dev, "Always in busy convertion.\n"); + return -EBUSY; + } + + for (i = 0; i < count; i++) { + ret = spi_read(spi_dev, (u8 *)&data[i], sizeof(data[i])); + if (ret < 0) { + dev_err(&spi_dev->dev, "SPI read error\n"); + return ret; + } + *data = be16_to_cpu(data[i]); + } + + return 0; +} + +static ssize_t ad7298_show_mode(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct ad7298_chip_info *chip = dev_info->dev_data; + + if (chip->command & AD7298_REPEAT) + return sprintf(buf, "repeat\n"); + else + return sprintf(buf, "normal\n"); +} + +static ssize_t ad7298_store_mode(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct ad7298_chip_info *chip = dev_info->dev_data; + + if (strcmp(buf, "repeat")) + chip->command |= AD7298_REPEAT; + else + chip->command &= (~AD7298_REPEAT); + + return 1; +} + +static IIO_DEVICE_ATTR(mode, S_IRUGO | S_IWUSR, + ad7298_show_mode, + ad7298_store_mode, + 0); + +static ssize_t ad7298_show_available_modes(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "normal\nrepeat\n"); +} + +static IIO_DEVICE_ATTR(available_modes, S_IRUGO, ad7298_show_available_modes, NULL, 0); + +static ssize_t ad7298_store_reset(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct ad7298_chip_info *chip = dev_info->dev_data; + u16 command; + int ret; + + command = chip->command & ~AD7298_PD; + + ret = ad7298_spi_write(chip, command); + if (ret) + return -EIO; + + command = chip->command | AD7298_PD; + + ret = ad7298_spi_write(chip, command); + if (ret) + return -EIO; + + return len; +} + +static IIO_DEVICE_ATTR(reset, S_IWUSR, + NULL, + ad7298_store_reset, + 0); + +static ssize_t ad7298_show_ext_ref(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct ad7298_chip_info *chip = dev_info->dev_data; + + return sprintf(buf, "%d\n", !!(chip->command & AD7298_EXT_REF)); +} + +static ssize_t ad7298_store_ext_ref(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct ad7298_chip_info *chip = dev_info->dev_data; + u16 command; + int ret; + + command = chip->command & (~AD7298_EXT_REF); + if (strcmp(buf, "1")) + command |= AD7298_EXT_REF; + + ret = ad7298_spi_write(chip, command); + if (ret) + return -EIO; + + chip->command = command; + + return len; +} + +static IIO_DEVICE_ATTR(ext_ref, S_IRUGO | S_IWUSR, + ad7298_show_ext_ref, + ad7298_store_ext_ref, + 0); + +static ssize_t ad7298_show_t_sense(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct ad7298_chip_info *chip = dev_info->dev_data; + u16 data; + char sign = ' '; + int ret; + + ret = ad7298_spi_read(chip, AD7298_T_SENSE_MASK, &data); + if (ret) + return -EIO; + + if (data & AD7298_T_VALUE_SIGN) { + /* convert supplement to positive value */ + data = (AD7298_T_VALUE_SIGN << 1) - data; + sign = '-'; + } + + return sprintf(buf, "%c%d.%.2d\n", sign, + (data >> AD7298_T_VALUE_FLOAT_OFFSET), + (data & AD7298_T_VALUE_FLOAT_MASK) * 25); +} + +static IIO_DEVICE_ATTR(t_sense, S_IRUGO, ad7298_show_t_sense, NULL, 0); + +static ssize_t ad7298_show_t_average(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct ad7298_chip_info *chip = dev_info->dev_data; + u16 data[2]; + char sign = ' '; + int ret; + + ret = ad7298_spi_read(chip, AD7298_T_AVG_MASK, data); + if (ret) + return -EIO; + + if (data[1] & AD7298_T_VALUE_SIGN) { + /* convert supplement to positive value */ + data[1] = (AD7298_T_VALUE_SIGN << 1) - data[1]; + sign = '-'; + } + + return sprintf(buf, "%c%d.%.2d\n", sign, + (data[1] >> AD7298_T_VALUE_FLOAT_OFFSET), + (data[1] & AD7298_T_VALUE_FLOAT_MASK) * 25); +} + +static IIO_DEVICE_ATTR(t_average, S_IRUGO, ad7298_show_t_average, NULL, 0); + +static ssize_t ad7298_show_voltage(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct ad7298_chip_info *chip = dev_info->dev_data; + u16 data[AD7298_VOLTAGE_LIMIT_COUNT]; + int i, size, ret; + + ret = ad7298_spi_read(chip, AD7298_VOLTAGE_MASK, data); + if (ret) + return -EIO; + + for (i = 0; i < AD7298_VOLTAGE_LIMIT_COUNT; i++) { + if (chip->command & (AD7298_T_SENSE_MASK << i)) { + ret = sprintf(buf, "channel[%d]=%d\n", i, + data[i] & AD7298_VALUE_MASK); + if (ret < 0) + break; + buf += ret; + size += ret; + } + } + + return size; +} + +static IIO_DEVICE_ATTR(voltage, S_IRUGO, ad7298_show_voltage, NULL, 0); + +static ssize_t ad7298_show_channel_mask(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct ad7298_chip_info *chip = dev_info->dev_data; + + return sprintf(buf, "0x%x\n", (chip->command & AD7298_VOLTAGE_MASK) >> + AD7298_VOLTAGE_OFFSET); +} + +static ssize_t ad7298_store_channel_mask(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct ad7298_chip_info *chip = dev_info->dev_data; + unsigned long data; + int i, ret; + + ret = strict_strtoul(buf, 16, &data); + if (ret || data > 0xff) + return -EINVAL; + + chip->command &= (~AD7298_VOLTAGE_MASK); + chip->command |= data << AD7298_VOLTAGE_OFFSET; + + for (i = 0, chip->channels = 0; i < AD7298_VOLTAGE_LIMIT_COUNT; i++) { + if (chip->command & (AD7298_T_SENSE_MASK << i)) + chip->channels++; + } + + return ret; +} + +static IIO_DEVICE_ATTR(channel_mask, S_IRUGO | S_IWUSR, + ad7298_show_channel_mask, + ad7298_store_channel_mask, + 0); + +static ssize_t ad7298_show_name(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct ad7298_chip_info *chip = dev_info->dev_data; + return sprintf(buf, "%s\n", chip->name); +} + +static IIO_DEVICE_ATTR(name, S_IRUGO, ad7298_show_name, NULL, 0); + +static struct attribute *ad7298_attributes[] = { + &iio_dev_attr_available_modes.dev_attr.attr, + &iio_dev_attr_mode.dev_attr.attr, + &iio_dev_attr_reset.dev_attr.attr, + &iio_dev_attr_ext_ref.dev_attr.attr, + &iio_dev_attr_t_sense.dev_attr.attr, + &iio_dev_attr_t_average.dev_attr.attr, + &iio_dev_attr_voltage.dev_attr.attr, + &iio_dev_attr_channel_mask.dev_attr.attr, + &iio_dev_attr_name.dev_attr.attr, + NULL, +}; + +static const struct attribute_group ad7298_attribute_group = { + .attrs = ad7298_attributes, +}; + +/* + * device probe and remove + */ +static int __devinit ad7298_probe(struct spi_device *spi_dev) +{ + struct ad7298_chip_info *chip; + unsigned short *pins = spi_dev->dev.platform_data; + int ret = 0; + + chip = kzalloc(sizeof(struct ad7298_chip_info), GFP_KERNEL); + + if (chip == NULL) + return -ENOMEM; + + /* this is only used for device removal purposes */ + dev_set_drvdata(&spi_dev->dev, chip); + + chip->spi_dev = spi_dev; + chip->name = spi_dev->modalias; + chip->busy_pin = pins[0]; + + ret = gpio_request(chip->busy_pin, chip->name); + if (ret) { + dev_err(&spi_dev->dev, "Fail to request busy gpio PIN %d.\n", + chip->busy_pin); + goto error_free_chip; + } + gpio_direction_input(chip->busy_pin); + + chip->indio_dev = iio_allocate_device(); + if (chip->indio_dev == NULL) { + ret = -ENOMEM; + goto error_free_gpio; + } + + chip->indio_dev->dev.parent = &spi_dev->dev; + chip->indio_dev->attrs = &ad7298_attribute_group; + chip->indio_dev->dev_data = (void *)chip; + chip->indio_dev->driver_module = THIS_MODULE; + chip->indio_dev->modes = INDIO_DIRECT_MODE; + + ret = iio_device_register(chip->indio_dev); + if (ret) + goto error_free_dev; + + dev_info(&spi_dev->dev, "%s temperature sensor and ADC registered.\n", + chip->name); + + return 0; + +error_free_dev: + iio_free_device(chip->indio_dev); +error_free_gpio: + gpio_free(chip->busy_pin); +error_free_chip: + kfree(chip); + + return ret; +} + +static int __devexit ad7298_remove(struct spi_device *spi_dev) +{ + struct ad7298_chip_info *chip = dev_get_drvdata(&spi_dev->dev); + struct iio_dev *indio_dev = chip->indio_dev; + + dev_set_drvdata(&spi_dev->dev, NULL); + iio_device_unregister(indio_dev); + iio_free_device(chip->indio_dev); + gpio_free(chip->busy_pin); + kfree(chip); + + return 0; +} + +static const struct spi_device_id ad7298_id[] = { + { "ad7298", 0 }, + {} +}; + +MODULE_DEVICE_TABLE(spi, ad7298_id); + +static struct spi_driver ad7298_driver = { + .driver = { + .name = "ad7298", + .bus = &spi_bus_type, + .owner = THIS_MODULE, + }, + .probe = ad7298_probe, + .remove = __devexit_p(ad7298_remove), + .id_table = ad7298_id, +}; + +static __init int ad7298_init(void) +{ + return spi_register_driver(&ad7298_driver); +} + +static __exit void ad7298_exit(void) +{ + spi_unregister_driver(&ad7298_driver); +} + +MODULE_AUTHOR("Sonic Zhang "); +MODULE_DESCRIPTION("Analog Devices AD7298 digital" + " temperature sensor and ADC driver"); +MODULE_LICENSE("GPL v2"); + +module_init(ad7298_init); +module_exit(ad7298_exit); -- 1.7.3.2