1 files changed, 603 insertions, 0 deletions

diff --git a/drivers/staging/iio/adc/ad7606_core.c b/drivers/staging/iio/adc/ad7606_core.c
new file mode 100644
index 000000000..bf2c80131
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7606_core.c
@@ -0,0 +1,603 @@
+/*
+ * AD7606 SPI ADC driver
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/regulator/consumer.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/module.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+
+#include "ad7606.h"
+
+int ad7606_reset(struct ad7606_state *st)
+{
+	if (gpio_is_valid(st->pdata->gpio_reset)) {
+		gpio_set_value(st->pdata->gpio_reset, 1);
+		ndelay(100); /* t_reset >= 100ns */
+		gpio_set_value(st->pdata->gpio_reset, 0);
+		return 0;
+	}
+
+	return -ENODEV;
+}
+
+static int ad7606_scan_direct(struct iio_dev *indio_dev, unsigned ch)
+{
+	struct ad7606_state *st = iio_priv(indio_dev);
+	int ret;
+
+	st->done = false;
+	gpio_set_value(st->pdata->gpio_convst, 1);
+
+	ret = wait_event_interruptible(st->wq_data_avail, st->done);
+	if (ret)
+		goto error_ret;
+
+	if (gpio_is_valid(st->pdata->gpio_frstdata)) {
+		ret = st->bops->read_block(st->dev, 1, st->data);
+		if (ret)
+			goto error_ret;
+		if (!gpio_get_value(st->pdata->gpio_frstdata)) {
+			/* This should never happen */
+			ad7606_reset(st);
+			ret = -EIO;
+			goto error_ret;
+		}
+		ret = st->bops->read_block(st->dev,
+			st->chip_info->num_channels - 1, &st->data[1]);
+		if (ret)
+			goto error_ret;
+	} else {
+		ret = st->bops->read_block(st->dev,
+			st->chip_info->num_channels, st->data);
+		if (ret)
+			goto error_ret;
+	}
+
+	ret = st->data[ch];
+
+error_ret:
+	gpio_set_value(st->pdata->gpio_convst, 0);
+
+	return ret;
+}
+
+static int ad7606_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val,
+			   int *val2,
+			   long m)
+{
+	int ret;
+	struct ad7606_state *st = iio_priv(indio_dev);
+
+	switch (m) {
+	case IIO_CHAN_INFO_RAW:
+		mutex_lock(&indio_dev->mlock);
+		if (iio_buffer_enabled(indio_dev))
+			ret = -EBUSY;
+		else
+			ret = ad7606_scan_direct(indio_dev, chan->address);
+		mutex_unlock(&indio_dev->mlock);
+
+		if (ret < 0)
+			return ret;
+		*val = (short) ret;
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		*val = st->range * 2;
+		*val2 = st->chip_info->channels[0].scan_type.realbits;
+		return IIO_VAL_FRACTIONAL_LOG2;
+	}
+	return -EINVAL;
+}
+
+static ssize_t ad7606_show_range(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct ad7606_state *st = iio_priv(indio_dev);
+
+	return sprintf(buf, "%u\n", st->range);
+}
+
+static ssize_t ad7606_store_range(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct ad7606_state *st = iio_priv(indio_dev);
+	unsigned long lval;
+	int ret;
+
+	ret = kstrtoul(buf, 10, &lval);
+	if (ret)
+		return ret;
+
+	if (!(lval == 5000 || lval == 10000)) {
+		dev_err(dev, "range is not supported\n");
+		return -EINVAL;
+	}
+	mutex_lock(&indio_dev->mlock);
+	gpio_set_value(st->pdata->gpio_range, lval == 10000);
+	st->range = lval;
+	mutex_unlock(&indio_dev->mlock);
+
+	return count;
+}
+
+static IIO_DEVICE_ATTR(in_voltage_range, S_IRUGO | S_IWUSR,
+		       ad7606_show_range, ad7606_store_range, 0);
+static IIO_CONST_ATTR(in_voltage_range_available, "5000 10000");
+
+static ssize_t ad7606_show_oversampling_ratio(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct ad7606_state *st = iio_priv(indio_dev);
+
+	return sprintf(buf, "%u\n", st->oversampling);
+}
+
+static int ad7606_oversampling_get_index(unsigned val)
+{
+	unsigned char supported[] = {0, 2, 4, 8, 16, 32, 64};
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(supported); i++)
+		if (val == supported[i])
+			return i;
+
+	return -EINVAL;
+}
+
+static ssize_t ad7606_store_oversampling_ratio(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct ad7606_state *st = iio_priv(indio_dev);
+	unsigned long lval;
+	int ret;
+
+	ret = kstrtoul(buf, 10, &lval);
+	if (ret)
+		return ret;
+
+	ret = ad7606_oversampling_get_index(lval);
+	if (ret < 0) {
+		dev_err(dev, "oversampling %lu is not supported\n", lval);
+		return ret;
+	}
+
+	mutex_lock(&indio_dev->mlock);
+	gpio_set_value(st->pdata->gpio_os0, (ret >> 0) & 1);
+	gpio_set_value(st->pdata->gpio_os1, (ret >> 1) & 1);
+	gpio_set_value(st->pdata->gpio_os1, (ret >> 2) & 1);
+	st->oversampling = lval;
+	mutex_unlock(&indio_dev->mlock);
+
+	return count;
+}
+
+static IIO_DEVICE_ATTR(oversampling_ratio, S_IRUGO | S_IWUSR,
+		       ad7606_show_oversampling_ratio,
+		       ad7606_store_oversampling_ratio, 0);
+static IIO_CONST_ATTR(oversampling_ratio_available, "0 2 4 8 16 32 64");
+
+static struct attribute *ad7606_attributes_os_and_range[] = {
+	&iio_dev_attr_in_voltage_range.dev_attr.attr,
+	&iio_const_attr_in_voltage_range_available.dev_attr.attr,
+	&iio_dev_attr_oversampling_ratio.dev_attr.attr,
+	&iio_const_attr_oversampling_ratio_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group ad7606_attribute_group_os_and_range = {
+	.attrs = ad7606_attributes_os_and_range,
+};
+
+static struct attribute *ad7606_attributes_os[] = {
+	&iio_dev_attr_oversampling_ratio.dev_attr.attr,
+	&iio_const_attr_oversampling_ratio_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group ad7606_attribute_group_os = {
+	.attrs = ad7606_attributes_os,
+};
+
+static struct attribute *ad7606_attributes_range[] = {
+	&iio_dev_attr_in_voltage_range.dev_attr.attr,
+	&iio_const_attr_in_voltage_range_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group ad7606_attribute_group_range = {
+	.attrs = ad7606_attributes_range,
+};
+
+#define AD7606_CHANNEL(num)					\
+	{							\
+		.type = IIO_VOLTAGE,				\
+		.indexed = 1,					\
+		.channel = num,					\
+		.address = num,					\
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
+		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\
+		.scan_index = num,				\
+		.scan_type = {					\
+			.sign = 's',				\
+			.realbits = 16,				\
+			.storagebits = 16,			\
+			.endianness = IIO_CPU,			\
+		},						\
+	}
+
+static const struct iio_chan_spec ad7606_8_channels[] = {
+	AD7606_CHANNEL(0),
+	AD7606_CHANNEL(1),
+	AD7606_CHANNEL(2),
+	AD7606_CHANNEL(3),
+	AD7606_CHANNEL(4),
+	AD7606_CHANNEL(5),
+	AD7606_CHANNEL(6),
+	AD7606_CHANNEL(7),
+	IIO_CHAN_SOFT_TIMESTAMP(8),
+};
+
+static const struct iio_chan_spec ad7606_6_channels[] = {
+	AD7606_CHANNEL(0),
+	AD7606_CHANNEL(1),
+	AD7606_CHANNEL(2),
+	AD7606_CHANNEL(3),
+	AD7606_CHANNEL(4),
+	AD7606_CHANNEL(5),
+	IIO_CHAN_SOFT_TIMESTAMP(6),
+};
+
+static const struct iio_chan_spec ad7606_4_channels[] = {
+	AD7606_CHANNEL(0),
+	AD7606_CHANNEL(1),
+	AD7606_CHANNEL(2),
+	AD7606_CHANNEL(3),
+	IIO_CHAN_SOFT_TIMESTAMP(4),
+};
+
+static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {
+	/*
+	 * More devices added in future
+	 */
+	[ID_AD7606_8] = {
+		.name = "ad7606",
+		.int_vref_mv = 2500,
+		.channels = ad7606_8_channels,
+		.num_channels = 8,
+	},
+	[ID_AD7606_6] = {
+		.name = "ad7606-6",
+		.int_vref_mv = 2500,
+		.channels = ad7606_6_channels,
+		.num_channels = 6,
+	},
+	[ID_AD7606_4] = {
+		.name = "ad7606-4",
+		.int_vref_mv = 2500,
+		.channels = ad7606_4_channels,
+		.num_channels = 4,
+	},
+};
+
+static int ad7606_request_gpios(struct ad7606_state *st)
+{
+	struct gpio gpio_array[3] = {
+		[0] = {
+			.gpio =  st->pdata->gpio_os0,
+			.flags = GPIOF_DIR_OUT | ((st->oversampling & 1) ?
+				 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
+			.label = "AD7606_OS0",
+		},
+		[1] = {
+			.gpio =  st->pdata->gpio_os1,
+			.flags = GPIOF_DIR_OUT | ((st->oversampling & 2) ?
+				 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
+			.label = "AD7606_OS1",
+		},
+		[2] = {
+			.gpio =  st->pdata->gpio_os2,
+			.flags = GPIOF_DIR_OUT | ((st->oversampling & 4) ?
+				 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
+			.label = "AD7606_OS2",
+		},
+	};
+	int ret;
+
+	if (gpio_is_valid(st->pdata->gpio_convst)) {
+		ret = gpio_request_one(st->pdata->gpio_convst,
+				       GPIOF_OUT_INIT_LOW,
+				       "AD7606_CONVST");
+		if (ret) {
+			dev_err(st->dev, "failed to request GPIO CONVST\n");
+			goto error_ret;
+		}
+	} else {
+		ret = -EIO;
+		goto error_ret;
+	}
+
+	if (gpio_is_valid(st->pdata->gpio_os0) &&
+	    gpio_is_valid(st->pdata->gpio_os1) &&
+	    gpio_is_valid(st->pdata->gpio_os2)) {
+		ret = gpio_request_array(gpio_array, ARRAY_SIZE(gpio_array));
+		if (ret < 0)
+			goto error_free_convst;
+	}
+
+	if (gpio_is_valid(st->pdata->gpio_reset)) {
+		ret = gpio_request_one(st->pdata->gpio_reset,
+				       GPIOF_OUT_INIT_LOW,
+				       "AD7606_RESET");
+		if (ret < 0)
+			goto error_free_os;
+	}
+
+	if (gpio_is_valid(st->pdata->gpio_range)) {
+		ret = gpio_request_one(st->pdata->gpio_range, GPIOF_DIR_OUT |
+				       ((st->range == 10000) ? GPIOF_INIT_HIGH :
+					GPIOF_INIT_LOW), "AD7606_RANGE");
+		if (ret < 0)
+			goto error_free_reset;
+	}
+	if (gpio_is_valid(st->pdata->gpio_stby)) {
+		ret = gpio_request_one(st->pdata->gpio_stby,
+				       GPIOF_OUT_INIT_HIGH,
+				       "AD7606_STBY");
+		if (ret < 0)
+			goto error_free_range;
+	}
+
+	if (gpio_is_valid(st->pdata->gpio_frstdata)) {
+		ret = gpio_request_one(st->pdata->gpio_frstdata, GPIOF_IN,
+				       "AD7606_FRSTDATA");
+		if (ret < 0)
+			goto error_free_stby;
+	}
+
+	return 0;
+
+error_free_stby:
+	if (gpio_is_valid(st->pdata->gpio_stby))
+		gpio_free(st->pdata->gpio_stby);
+error_free_range:
+	if (gpio_is_valid(st->pdata->gpio_range))
+		gpio_free(st->pdata->gpio_range);
+error_free_reset:
+	if (gpio_is_valid(st->pdata->gpio_reset))
+		gpio_free(st->pdata->gpio_reset);
+error_free_os:
+	if (gpio_is_valid(st->pdata->gpio_os0) &&
+	    gpio_is_valid(st->pdata->gpio_os1) &&
+	    gpio_is_valid(st->pdata->gpio_os2))
+		gpio_free_array(gpio_array, ARRAY_SIZE(gpio_array));
+error_free_convst:
+	gpio_free(st->pdata->gpio_convst);
+error_ret:
+	return ret;
+}
+
+static void ad7606_free_gpios(struct ad7606_state *st)
+{
+	if (gpio_is_valid(st->pdata->gpio_frstdata))
+		gpio_free(st->pdata->gpio_frstdata);
+	if (gpio_is_valid(st->pdata->gpio_stby))
+		gpio_free(st->pdata->gpio_stby);
+	if (gpio_is_valid(st->pdata->gpio_range))
+		gpio_free(st->pdata->gpio_range);
+	if (gpio_is_valid(st->pdata->gpio_reset))
+		gpio_free(st->pdata->gpio_reset);
+	if (gpio_is_valid(st->pdata->gpio_os0) &&
+	    gpio_is_valid(st->pdata->gpio_os1) &&
+	    gpio_is_valid(st->pdata->gpio_os2)) {
+		gpio_free(st->pdata->gpio_os2);
+		gpio_free(st->pdata->gpio_os1);
+		gpio_free(st->pdata->gpio_os0);
+	}
+	gpio_free(st->pdata->gpio_convst);
+}
+
+/**
+ *  Interrupt handler
+ */
+static irqreturn_t ad7606_interrupt(int irq, void *dev_id)
+{
+	struct iio_dev *indio_dev = dev_id;
+	struct ad7606_state *st = iio_priv(indio_dev);
+
+	if (iio_buffer_enabled(indio_dev)) {
+		schedule_work(&st->poll_work);
+	} else {
+		st->done = true;
+		wake_up_interruptible(&st->wq_data_avail);
+	}
+
+	return IRQ_HANDLED;
+};
+
+static const struct iio_info ad7606_info_no_os_or_range = {
+	.driver_module = THIS_MODULE,
+	.read_raw = &ad7606_read_raw,
+};
+
+static const struct iio_info ad7606_info_os_and_range = {
+	.driver_module = THIS_MODULE,
+	.read_raw = &ad7606_read_raw,
+	.attrs = &ad7606_attribute_group_os_and_range,
+};
+
+static const struct iio_info ad7606_info_os = {
+	.driver_module = THIS_MODULE,
+	.read_raw = &ad7606_read_raw,
+	.attrs = &ad7606_attribute_group_os,
+};
+
+static const struct iio_info ad7606_info_range = {
+	.driver_module = THIS_MODULE,
+	.read_raw = &ad7606_read_raw,
+	.attrs = &ad7606_attribute_group_range,
+};
+
+struct iio_dev *ad7606_probe(struct device *dev, int irq,
+			      void __iomem *base_address,
+			      unsigned id,
+			      const struct ad7606_bus_ops *bops)
+{
+	struct ad7606_platform_data *pdata = dev->platform_data;
+	struct ad7606_state *st;
+	int ret;
+	struct iio_dev *indio_dev;
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
+	if (!indio_dev)
+		return ERR_PTR(-ENOMEM);
+
+	st = iio_priv(indio_dev);
+
+	st->dev = dev;
+	st->bops = bops;
+	st->base_address = base_address;
+	st->range = pdata->default_range == 10000 ? 10000 : 5000;
+
+	ret = ad7606_oversampling_get_index(pdata->default_os);
+	if (ret < 0) {
+		dev_warn(dev, "oversampling %d is not supported\n",
+			 pdata->default_os);
+		st->oversampling = 0;
+	} else {
+		st->oversampling = pdata->default_os;
+	}
+
+	st->reg = devm_regulator_get(dev, "vcc");
+	if (!IS_ERR(st->reg)) {
+		ret = regulator_enable(st->reg);
+		if (ret)
+			return ERR_PTR(ret);
+	}
+
+	st->pdata = pdata;
+	st->chip_info = &ad7606_chip_info_tbl[id];
+
+	indio_dev->dev.parent = dev;
+	if (gpio_is_valid(st->pdata->gpio_os0) &&
+	    gpio_is_valid(st->pdata->gpio_os1) &&
+	    gpio_is_valid(st->pdata->gpio_os2)) {
+		if (gpio_is_valid(st->pdata->gpio_range))
+			indio_dev->info = &ad7606_info_os_and_range;
+		else
+			indio_dev->info = &ad7606_info_os;
+	} else {
+		if (gpio_is_valid(st->pdata->gpio_range))
+			indio_dev->info = &ad7606_info_range;
+		else
+			indio_dev->info = &ad7606_info_no_os_or_range;
+	}
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->name = st->chip_info->name;
+	indio_dev->channels = st->chip_info->channels;
+	indio_dev->num_channels = st->chip_info->num_channels;
+
+	init_waitqueue_head(&st->wq_data_avail);
+
+	ret = ad7606_request_gpios(st);
+	if (ret)
+		goto error_disable_reg;
+
+	ret = ad7606_reset(st);
+	if (ret)
+		dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");
+
+	ret = request_irq(irq, ad7606_interrupt,
+		IRQF_TRIGGER_FALLING, st->chip_info->name, indio_dev);
+	if (ret)
+		goto error_free_gpios;
+
+	ret = ad7606_register_ring_funcs_and_init(indio_dev);
+	if (ret)
+		goto error_free_irq;
+
+	ret = iio_device_register(indio_dev);
+	if (ret)
+		goto error_unregister_ring;
+
+	return indio_dev;
+error_unregister_ring:
+	ad7606_ring_cleanup(indio_dev);
+
+error_free_irq:
+	free_irq(irq, indio_dev);
+
+error_free_gpios:
+	ad7606_free_gpios(st);
+
+error_disable_reg:
+	if (!IS_ERR(st->reg))
+		regulator_disable(st->reg);
+	return ERR_PTR(ret);
+}
+
+int ad7606_remove(struct iio_dev *indio_dev, int irq)
+{
+	struct ad7606_state *st = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+	ad7606_ring_cleanup(indio_dev);
+
+	free_irq(irq, indio_dev);
+	if (!IS_ERR(st->reg))
+		regulator_disable(st->reg);
+
+	ad7606_free_gpios(st);
+
+	return 0;
+}
+
+void ad7606_suspend(struct iio_dev *indio_dev)
+{
+	struct ad7606_state *st = iio_priv(indio_dev);
+
+	if (gpio_is_valid(st->pdata->gpio_stby)) {
+		if (gpio_is_valid(st->pdata->gpio_range))
+			gpio_set_value(st->pdata->gpio_range, 1);
+		gpio_set_value(st->pdata->gpio_stby, 0);
+	}
+}
+
+void ad7606_resume(struct iio_dev *indio_dev)
+{
+	struct ad7606_state *st = iio_priv(indio_dev);
+
+	if (gpio_is_valid(st->pdata->gpio_stby)) {
+		if (gpio_is_valid(st->pdata->gpio_range))
+			gpio_set_value(st->pdata->gpio_range,
+					st->range == 10000);
+
+		gpio_set_value(st->pdata->gpio_stby, 1);
+		ad7606_reset(st);
+	}
+}
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
+MODULE_LICENSE("GPL v2");