sensor is associated with one part of a compound device (e.g.
a gyroscope axis).
+What: /sys/bus/iio/devices/deviceX/tempX_input
+KernelVersion: 2.6.38
+Contact: linux-iio@vger.kernel.org
+Description:
+ Scaled temperature measurement in milli degrees Celsius.
+
What: /sys/bus/iio/devices/deviceX/accel_x_raw
What: /sys/bus/iio/devices/deviceX/accel_y_raw
What: /sys/bus/iio/devices/deviceX/accel_z_raw
temperature sensors.
config AD7298
- tristate "Analog Devices AD7298 temperature sensor and ADC driver"
+ tristate "Analog Devices AD7298 ADC driver"
depends on SPI
help
Say yes here to build support for Analog Devices AD7298
- temperature sensors and ADC.
+ 8 Channel ADC with temperature sensor.
+
+ To compile this driver as a module, choose M here: the
+ module will be called ad7298.
config AD7314
tristate "Analog Devices AD7314 temperature sensor driver"
ad7887-$(CONFIG_IIO_RING_BUFFER) += ad7887_ring.o
obj-$(CONFIG_AD7887) += ad7887.o
+ad7298-y := ad7298_core.o
+ad7298-$(CONFIG_IIO_RING_BUFFER) += ad7298_ring.o
+obj-$(CONFIG_AD7298) += ad7298.o
+
obj-$(CONFIG_AD7150) += ad7150.o
obj-$(CONFIG_AD7152) += ad7152.o
obj-$(CONFIG_AD7291) += ad7291.o
-obj-$(CONFIG_AD7298) += ad7298.o
obj-$(CONFIG_AD7314) += ad7314.o
obj-$(CONFIG_AD7745) += ad7745.o
obj-$(CONFIG_AD7816) += ad7816.o
+++ /dev/null
-/*
- * AD7298 digital temperature sensor driver supporting AD7298
- *
- * Copyright 2010 Analog Devices Inc.
- *
- * Licensed under the GPL-2 or later.
- */
-
-#include <linux/interrupt.h>
-#include <linux/gpio.h>
-#include <linux/workqueue.h>
-#include <linux/device.h>
-#include <linux/kernel.h>
-#include <linux/slab.h>
-#include <linux/sysfs.h>
-#include <linux/list.h>
-#include <linux/spi/spi.h>
-#include <linux/rtc.h>
-
-#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 <sonic.zhang@analog.com>");
-MODULE_DESCRIPTION("Analog Devices AD7298 digital"
- " temperature sensor and ADC driver");
-MODULE_LICENSE("GPL v2");
-
-module_init(ad7298_init);
-module_exit(ad7298_exit);
--- /dev/null
+/*
+ * AD7298 SPI ADC driver
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#ifndef IIO_ADC_AD7298_H_
+#define IIO_ADC_AD7298_H_
+
+#define AD7298_WRITE (1 << 15) /* write to the control register */
+#define AD7298_REPEAT (1 << 14) /* repeated conversion enable */
+#define AD7298_CH(x) (1 << (13 - (x))) /* channel select */
+#define AD7298_TSENSE (1 << 5) /* temperature conversion enable */
+#define AD7298_EXTREF (1 << 2) /* external reference enable */
+#define AD7298_TAVG (1 << 1) /* temperature sensor averaging enable */
+#define AD7298_PDD (1 << 0) /* partial power down enable */
+
+#define AD7298_CH_MASK (AD7298_CH0 | AD7298_CH1 | AD7298_CH2 | AD7298_CH3 | \
+ AD7298_CH4 | AD7298_CH5 | AD7298_CH6 | AD7298_CH7)
+
+#define AD7298_MAX_CHAN 8
+#define AD7298_BITS 12
+#define AD7298_STORAGE_BITS 16
+#define AD7298_INTREF_mV 2500
+
+#define RES_MASK(bits) ((1 << (bits)) - 1)
+
+/*
+ * TODO: struct ad7298_platform_data needs to go into include/linux/iio
+ */
+
+struct ad7298_platform_data {
+ /* External Vref voltage applied */
+ u16 vref_mv;
+};
+
+struct ad7298_state {
+ struct iio_dev *indio_dev;
+ struct spi_device *spi;
+ struct regulator *reg;
+ struct work_struct poll_work;
+ atomic_t protect_ring;
+ size_t d_size;
+ u16 int_vref_mv;
+ unsigned ext_ref;
+ struct spi_transfer ring_xfer[10];
+ struct spi_transfer scan_single_xfer[3];
+ struct spi_message ring_msg;
+ struct spi_message scan_single_msg;
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+ unsigned short rx_buf[8] ____cacheline_aligned;
+ unsigned short tx_buf[2];
+};
+
+#ifdef CONFIG_IIO_RING_BUFFER
+int ad7298_scan_from_ring(struct ad7298_state *st, long ch);
+int ad7298_register_ring_funcs_and_init(struct iio_dev *indio_dev);
+void ad7298_ring_cleanup(struct iio_dev *indio_dev);
+#else /* CONFIG_IIO_RING_BUFFER */
+static inline int ad7298_scan_from_ring(struct ad7298_state *st, long ch)
+{
+ return 0;
+}
+
+static inline int
+ad7298_register_ring_funcs_and_init(struct iio_dev *indio_dev)
+{
+ return 0;
+}
+
+static inline void ad7298_ring_cleanup(struct iio_dev *indio_dev)
+{
+}
+#endif /* CONFIG_IIO_RING_BUFFER */
+#endif /* IIO_ADC_AD7298_H_ */
--- /dev/null
+/*
+ * AD7298 SPI ADC driver
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/workqueue.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/spi/spi.h>
+#include <linux/regulator/consumer.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+
+#include "../iio.h"
+#include "../sysfs.h"
+#include "../ring_generic.h"
+#include "adc.h"
+
+#include "ad7298.h"
+
+static int ad7298_scan_direct(struct ad7298_state *st, unsigned ch)
+{
+ int ret;
+ st->tx_buf[0] = cpu_to_be16(AD7298_WRITE | st->ext_ref |
+ (AD7298_CH(0) >> ch));
+
+ ret = spi_sync(st->spi, &st->scan_single_msg);
+ if (ret)
+ return ret;
+
+ return be16_to_cpu(st->rx_buf[0]);
+}
+
+static ssize_t ad7298_scan(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *dev_info = dev_get_drvdata(dev);
+ struct ad7298_state *st = dev_info->dev_data;
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+ int ret;
+
+ mutex_lock(&dev_info->mlock);
+ if (iio_ring_enabled(dev_info))
+ ret = ad7298_scan_from_ring(st, this_attr->address);
+ else
+ ret = ad7298_scan_direct(st, this_attr->address);
+ mutex_unlock(&dev_info->mlock);
+
+ if (ret < 0)
+ return ret;
+
+ return sprintf(buf, "%d\n", ret & RES_MASK(AD7298_BITS));
+}
+
+static IIO_DEV_ATTR_IN_RAW(0, ad7298_scan, 0);
+static IIO_DEV_ATTR_IN_RAW(1, ad7298_scan, 1);
+static IIO_DEV_ATTR_IN_RAW(2, ad7298_scan, 2);
+static IIO_DEV_ATTR_IN_RAW(3, ad7298_scan, 3);
+static IIO_DEV_ATTR_IN_RAW(4, ad7298_scan, 4);
+static IIO_DEV_ATTR_IN_RAW(5, ad7298_scan, 5);
+static IIO_DEV_ATTR_IN_RAW(6, ad7298_scan, 6);
+static IIO_DEV_ATTR_IN_RAW(7, ad7298_scan, 7);
+
+static ssize_t ad7298_show_temp(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *dev_info = dev_get_drvdata(dev);
+ struct ad7298_state *st = iio_dev_get_devdata(dev_info);
+ int tmp;
+
+ tmp = cpu_to_be16(AD7298_WRITE | AD7298_TSENSE |
+ AD7298_TAVG | st->ext_ref);
+
+ mutex_lock(&dev_info->mlock);
+ spi_write(st->spi, (u8 *)&tmp, 2);
+ tmp = 0;
+ spi_write(st->spi, (u8 *)&tmp, 2);
+ usleep_range(101, 1000); /* sleep > 100us */
+ spi_read(st->spi, (u8 *)&tmp, 2);
+ mutex_unlock(&dev_info->mlock);
+
+ tmp = be16_to_cpu(tmp) & RES_MASK(AD7298_BITS);
+
+ /*
+ * One LSB of the ADC corresponds to 0.25 deg C.
+ * The temperature reading is in 12-bit twos complement format
+ */
+
+ if (tmp & (1 << (AD7298_BITS - 1))) {
+ tmp = (4096 - tmp) * 250;
+ tmp -= (2 * tmp);
+
+ } else {
+ tmp *= 250; /* temperature in milli degrees Celsius */
+ }
+
+ return sprintf(buf, "%d\n", tmp);
+}
+
+static IIO_DEVICE_ATTR(temp0_input, S_IRUGO, ad7298_show_temp, NULL, 0);
+
+static ssize_t ad7298_show_scale(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *dev_info = dev_get_drvdata(dev);
+ struct ad7298_state *st = iio_dev_get_devdata(dev_info);
+ /* Corresponds to Vref / 2^(bits) */
+ unsigned int scale_uv = (st->int_vref_mv * 1000) >> AD7298_BITS;
+
+ return sprintf(buf, "%d.%03d\n", scale_uv / 1000, scale_uv % 1000);
+}
+static IIO_DEVICE_ATTR(in_scale, S_IRUGO, ad7298_show_scale, NULL, 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_state *st = iio_dev_get_devdata(dev_info);
+
+ return sprintf(buf, "%s\n", spi_get_device_id(st->spi)->name);
+}
+static IIO_DEVICE_ATTR(name, S_IRUGO, ad7298_show_name, NULL, 0);
+
+static struct attribute *ad7298_attributes[] = {
+ &iio_dev_attr_in0_raw.dev_attr.attr,
+ &iio_dev_attr_in1_raw.dev_attr.attr,
+ &iio_dev_attr_in2_raw.dev_attr.attr,
+ &iio_dev_attr_in3_raw.dev_attr.attr,
+ &iio_dev_attr_in4_raw.dev_attr.attr,
+ &iio_dev_attr_in5_raw.dev_attr.attr,
+ &iio_dev_attr_in6_raw.dev_attr.attr,
+ &iio_dev_attr_in7_raw.dev_attr.attr,
+ &iio_dev_attr_in_scale.dev_attr.attr,
+ &iio_dev_attr_temp0_input.dev_attr.attr,
+ &iio_dev_attr_name.dev_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group ad7298_attribute_group = {
+ .attrs = ad7298_attributes,
+};
+
+static int __devinit ad7298_probe(struct spi_device *spi)
+{
+ struct ad7298_platform_data *pdata = spi->dev.platform_data;
+ struct ad7298_state *st;
+ int ret;
+
+ st = kzalloc(sizeof(*st), GFP_KERNEL);
+ if (st == NULL) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+
+ st->reg = regulator_get(&spi->dev, "vcc");
+ if (!IS_ERR(st->reg)) {
+ ret = regulator_enable(st->reg);
+ if (ret)
+ goto error_put_reg;
+ }
+
+ spi_set_drvdata(spi, st);
+
+ atomic_set(&st->protect_ring, 0);
+ st->spi = spi;
+
+ st->indio_dev = iio_allocate_device();
+ if (st->indio_dev == NULL) {
+ ret = -ENOMEM;
+ goto error_disable_reg;
+ }
+
+ st->indio_dev->dev.parent = &spi->dev;
+ st->indio_dev->attrs = &ad7298_attribute_group;
+ st->indio_dev->dev_data = (void *)(st);
+ st->indio_dev->driver_module = THIS_MODULE;
+ st->indio_dev->modes = INDIO_DIRECT_MODE;
+
+ /* Setup default message */
+
+ st->scan_single_xfer[0].tx_buf = &st->tx_buf[0];
+ st->scan_single_xfer[0].len = 2;
+ st->scan_single_xfer[0].cs_change = 1;
+ st->scan_single_xfer[1].tx_buf = &st->tx_buf[1];
+ st->scan_single_xfer[1].len = 2;
+ st->scan_single_xfer[1].cs_change = 1;
+ st->scan_single_xfer[2].rx_buf = &st->rx_buf[0];
+ st->scan_single_xfer[2].len = 2;
+
+ spi_message_init(&st->scan_single_msg);
+ spi_message_add_tail(&st->scan_single_xfer[0], &st->scan_single_msg);
+ spi_message_add_tail(&st->scan_single_xfer[1], &st->scan_single_msg);
+ spi_message_add_tail(&st->scan_single_xfer[2], &st->scan_single_msg);
+
+ if (pdata && pdata->vref_mv) {
+ st->int_vref_mv = pdata->vref_mv;
+ st->ext_ref = AD7298_EXTREF;
+ } else {
+ st->int_vref_mv = AD7298_INTREF_mV;
+ }
+
+ ret = ad7298_register_ring_funcs_and_init(st->indio_dev);
+ if (ret)
+ goto error_free_device;
+
+ ret = iio_device_register(st->indio_dev);
+ if (ret)
+ goto error_free_device;
+
+ ret = iio_ring_buffer_register(st->indio_dev->ring, 0);
+ if (ret)
+ goto error_cleanup_ring;
+ return 0;
+
+error_cleanup_ring:
+ ad7298_ring_cleanup(st->indio_dev);
+ iio_device_unregister(st->indio_dev);
+error_free_device:
+ iio_free_device(st->indio_dev);
+error_disable_reg:
+ if (!IS_ERR(st->reg))
+ regulator_disable(st->reg);
+error_put_reg:
+ if (!IS_ERR(st->reg))
+ regulator_put(st->reg);
+ kfree(st);
+error_ret:
+ return ret;
+}
+
+static int __devexit ad7298_remove(struct spi_device *spi)
+{
+ struct ad7298_state *st = spi_get_drvdata(spi);
+ struct iio_dev *indio_dev = st->indio_dev;
+
+ iio_ring_buffer_unregister(indio_dev->ring);
+ ad7298_ring_cleanup(indio_dev);
+ iio_device_unregister(indio_dev);
+ if (!IS_ERR(st->reg)) {
+ regulator_disable(st->reg);
+ regulator_put(st->reg);
+ }
+ kfree(st);
+ return 0;
+}
+
+static const struct spi_device_id ad7298_id[] = {
+ {"ad7298", 0},
+ {}
+};
+
+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 int __init ad7298_init(void)
+{
+ return spi_register_driver(&ad7298_driver);
+}
+module_init(ad7298_init);
+
+static void __exit ad7298_exit(void)
+{
+ spi_unregister_driver(&ad7298_driver);
+}
+module_exit(ad7298_exit);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("Analog Devices AD7298 ADC");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("spi:ad7298");
--- /dev/null
+/*
+ * AD7298 SPI ADC driver
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/workqueue.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/spi/spi.h>
+
+#include "../iio.h"
+#include "../ring_generic.h"
+#include "../ring_sw.h"
+#include "../trigger.h"
+#include "../sysfs.h"
+
+#include "ad7298.h"
+
+static IIO_SCAN_EL_C(in0, 0, 0, NULL);
+static IIO_SCAN_EL_C(in1, 1, 0, NULL);
+static IIO_SCAN_EL_C(in2, 2, 0, NULL);
+static IIO_SCAN_EL_C(in3, 3, 0, NULL);
+static IIO_SCAN_EL_C(in4, 4, 0, NULL);
+static IIO_SCAN_EL_C(in5, 5, 0, NULL);
+static IIO_SCAN_EL_C(in6, 6, 0, NULL);
+static IIO_SCAN_EL_C(in7, 7, 0, NULL);
+
+static IIO_SCAN_EL_TIMESTAMP(8);
+static IIO_CONST_ATTR_SCAN_EL_TYPE(timestamp, s, 64, 64);
+
+static IIO_CONST_ATTR(in_type, "u12/16") ;
+
+static struct attribute *ad7298_scan_el_attrs[] = {
+ &iio_scan_el_in0.dev_attr.attr,
+ &iio_const_attr_in0_index.dev_attr.attr,
+ &iio_scan_el_in1.dev_attr.attr,
+ &iio_const_attr_in1_index.dev_attr.attr,
+ &iio_scan_el_in2.dev_attr.attr,
+ &iio_const_attr_in2_index.dev_attr.attr,
+ &iio_scan_el_in3.dev_attr.attr,
+ &iio_const_attr_in3_index.dev_attr.attr,
+ &iio_scan_el_in4.dev_attr.attr,
+ &iio_const_attr_in4_index.dev_attr.attr,
+ &iio_scan_el_in5.dev_attr.attr,
+ &iio_const_attr_in5_index.dev_attr.attr,
+ &iio_scan_el_in6.dev_attr.attr,
+ &iio_const_attr_in6_index.dev_attr.attr,
+ &iio_scan_el_in7.dev_attr.attr,
+ &iio_const_attr_in7_index.dev_attr.attr,
+ &iio_const_attr_timestamp_index.dev_attr.attr,
+ &iio_scan_el_timestamp.dev_attr.attr,
+ &iio_const_attr_timestamp_type.dev_attr.attr,
+ &iio_const_attr_in_type.dev_attr.attr,
+ NULL,
+};
+
+static struct attribute_group ad7298_scan_el_group = {
+ .name = "scan_elements",
+ .attrs = ad7298_scan_el_attrs,
+};
+
+int ad7298_scan_from_ring(struct ad7298_state *st, long ch)
+{
+ struct iio_ring_buffer *ring = st->indio_dev->ring;
+ int ret;
+ u16 *ring_data;
+
+ if (!(ring->scan_mask & (1 << ch))) {
+ ret = -EBUSY;
+ goto error_ret;
+ }
+
+ ring_data = kmalloc(ring->access.get_bytes_per_datum(ring), GFP_KERNEL);
+ if (ring_data == NULL) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+ ret = ring->access.read_last(ring, (u8 *) ring_data);
+ if (ret)
+ goto error_free_ring_data;
+
+ ret = be16_to_cpu(ring_data[ch]);
+
+error_free_ring_data:
+ kfree(ring_data);
+error_ret:
+ return ret;
+}
+
+/**
+ * ad7298_ring_preenable() setup the parameters of the ring before enabling
+ *
+ * The complex nature of the setting of the number of bytes per datum is due
+ * to this driver currently ensuring that the timestamp is stored at an 8
+ * byte boundary.
+ **/
+static int ad7298_ring_preenable(struct iio_dev *indio_dev)
+{
+ struct ad7298_state *st = indio_dev->dev_data;
+ struct iio_ring_buffer *ring = indio_dev->ring;
+ size_t d_size;
+ int i, m;
+ unsigned short command;
+
+ d_size = ring->scan_count * (AD7298_STORAGE_BITS / 8);
+
+ if (ring->scan_timestamp) {
+ d_size += sizeof(s64);
+
+ if (d_size % sizeof(s64))
+ d_size += sizeof(s64) - (d_size % sizeof(s64));
+ }
+
+ if (ring->access.set_bytes_per_datum)
+ ring->access.set_bytes_per_datum(ring, d_size);
+
+ st->d_size = d_size;
+
+ command = AD7298_WRITE | st->ext_ref;
+
+ for (i = 0, m = AD7298_CH(0); i < AD7298_MAX_CHAN; i++, m >>= 1)
+ if (ring->scan_mask & (1 << i))
+ command |= m;
+
+ st->tx_buf[0] = cpu_to_be16(command);
+
+ /* build spi ring message */
+ st->ring_xfer[0].tx_buf = &st->tx_buf[0];
+ st->ring_xfer[0].len = 2;
+ st->ring_xfer[0].cs_change = 1;
+ st->ring_xfer[1].tx_buf = &st->tx_buf[1];
+ st->ring_xfer[1].len = 2;
+ st->ring_xfer[1].cs_change = 1;
+
+ spi_message_init(&st->ring_msg);
+ spi_message_add_tail(&st->ring_xfer[0], &st->ring_msg);
+ spi_message_add_tail(&st->ring_xfer[1], &st->ring_msg);
+
+ for (i = 0; i < ring->scan_count; i++) {
+ st->ring_xfer[i + 2].rx_buf = &st->rx_buf[i];
+ st->ring_xfer[i + 2].len = 2;
+ st->ring_xfer[i + 2].cs_change = 1;
+ spi_message_add_tail(&st->ring_xfer[i + 2], &st->ring_msg);
+ }
+ /* make sure last transfer cs_change is not set */
+ st->ring_xfer[i + 1].cs_change = 0;
+
+ return 0;
+}
+
+/**
+ * ad7298_poll_func_th() th of trigger launched polling to ring buffer
+ *
+ * As sampling only occurs on spi comms occuring, leave timestamping until
+ * then. Some triggers will generate their own time stamp. Currently
+ * there is no way of notifying them when no one cares.
+ **/
+static void ad7298_poll_func_th(struct iio_dev *indio_dev, s64 time)
+{
+ struct ad7298_state *st = indio_dev->dev_data;
+
+ schedule_work(&st->poll_work);
+ return;
+}
+
+/**
+ * ad7298_poll_bh_to_ring() bh of trigger launched polling to ring buffer
+ * @work_s: the work struct through which this was scheduled
+ *
+ * Currently there is no option in this driver to disable the saving of
+ * timestamps within the ring.
+ * I think the one copy of this at a time was to avoid problems if the
+ * trigger was set far too high and the reads then locked up the computer.
+ **/
+static void ad7298_poll_bh_to_ring(struct work_struct *work_s)
+{
+ struct ad7298_state *st = container_of(work_s, struct ad7298_state,
+ poll_work);
+ struct iio_dev *indio_dev = st->indio_dev;
+ struct iio_sw_ring_buffer *sw_ring = iio_to_sw_ring(indio_dev->ring);
+ struct iio_ring_buffer *ring = indio_dev->ring;
+ s64 time_ns;
+ __u16 buf[16];
+ int b_sent, i;
+
+ /* Ensure only one copy of this function running at a time */
+ if (atomic_inc_return(&st->protect_ring) > 1)
+ return;
+
+ b_sent = spi_sync(st->spi, &st->ring_msg);
+ if (b_sent)
+ goto done;
+
+ if (ring->scan_timestamp) {
+ time_ns = iio_get_time_ns();
+ memcpy((u8 *)buf + st->d_size - sizeof(s64),
+ &time_ns, sizeof(time_ns));
+ }
+
+ for (i = 0; i < ring->scan_count; i++)
+ buf[i] = be16_to_cpu(st->rx_buf[i]);
+
+ indio_dev->ring->access.store_to(&sw_ring->buf, (u8 *)buf, time_ns);
+done:
+ atomic_dec(&st->protect_ring);
+}
+
+int ad7298_register_ring_funcs_and_init(struct iio_dev *indio_dev)
+{
+ struct ad7298_state *st = indio_dev->dev_data;
+ int ret;
+
+ indio_dev->ring = iio_sw_rb_allocate(indio_dev);
+ if (!indio_dev->ring) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+ /* Effectively select the ring buffer implementation */
+ iio_ring_sw_register_funcs(&indio_dev->ring->access);
+ ret = iio_alloc_pollfunc(indio_dev, NULL, &ad7298_poll_func_th);
+ if (ret)
+ goto error_deallocate_sw_rb;
+
+ /* Ring buffer functions - here trigger setup related */
+
+ indio_dev->ring->preenable = &ad7298_ring_preenable;
+ indio_dev->ring->postenable = &iio_triggered_ring_postenable;
+ indio_dev->ring->predisable = &iio_triggered_ring_predisable;
+ indio_dev->ring->scan_el_attrs = &ad7298_scan_el_group;
+ indio_dev->ring->scan_timestamp = true;
+
+ INIT_WORK(&st->poll_work, &ad7298_poll_bh_to_ring);
+
+ /* Flag that polled ring buffering is possible */
+ indio_dev->modes |= INDIO_RING_TRIGGERED;
+ return 0;
+error_deallocate_sw_rb:
+ iio_sw_rb_free(indio_dev->ring);
+error_ret:
+ return ret;
+}
+
+void ad7298_ring_cleanup(struct iio_dev *indio_dev)
+{
+ if (indio_dev->trig) {
+ iio_put_trigger(indio_dev->trig);
+ iio_trigger_dettach_poll_func(indio_dev->trig,
+ indio_dev->pollfunc);
+ }
+ kfree(indio_dev->pollfunc);
+ iio_sw_rb_free(indio_dev->ring);
+}
projects / linux-beck.git / commitdiff