[PATCH v2 1/6] staging:iio: Add extended IIO channel info

[PATCH v2 1/6] staging:iio: Add extended IIO channel info

[Lars-Peter Clausen]

Sometimes devices have per channel properties which either do not map nicely to
the current channel info scheme (e.g. string properties) or are very device
specific, so it does not make sense to add generic support for them.

Currently drivers define these attributes by hand for each channel. Depending on
the number of channels this can amount to quite a few lines of boilerplate code.
Especially if a driver supports multiple variations of a chip with different
numbers of channels. In this case it becomes necessary to have a individual
attribute list per chip variation and also a individual iio_info struct.

This patch introduces a new scheme for handling such per channel attributes
called extended channel info attributes. A extended channel info attribute
consist of a name, a flag whether it is shared and read and write callbacks.
The read and write callbacks are similar to the {read,write}_raw callbacks and
take a IIO device and a channel as their first parameters, but instead of
pre-parsed integer values they directly get passed the raw string value, which
has been written to the sysfs file.

It is possible to assign a list of extended channel info attributes to a
channel. For each extended channel info attribute the IIO core will create a new
sysfs attribute conforming to the IIO channel naming spec for the channels type,
similar as for normal info attributes. Read and write access to this sysfs
attribute will be redirected to the extended channel info attributes read and
write callbacks.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>

---
Changes since v1:
	* Do not move the -EBUSY handling for duplicated shared attributes to
	  __iio_add_chan_devattr since it will cause us to count shared attributes
	  multiple times, thus allocating more attributes than we actually use.
---
 drivers/staging/iio/iio.h               |   23 +++++++++++++
 drivers/staging/iio/industrialio-core.c |   54 +++++++++++++++++++++++++++++++
 2 files changed, 77 insertions(+), 0 deletions(-)

diff --git a/drivers/staging/iio/iio.h b/drivers/staging/iio/iio.h
index be6ced3..9140c2a 100644
--- a/drivers/staging/iio/iio.h
+++ b/drivers/staging/iio/iio.h
@@ -88,6 +88,25 @@ enum iio_endian {
 	IIO_LE,
 };
 
+struct iio_chan_spec;
+struct iio_dev;
+
+/**
+ * struct iio_chan_spec_ext_info - Extended channel info attribute
+ * @name:	Info attribute name
+ * @shared:	Whether this attribute is shared between all channels.
+ * @read:	Read callback for this info attribute, may be NULL.
+ * @write:	Write callback for this info attribute, may be NULL.
+ */
+struct iio_chan_spec_ext_info {
+	const char *name;
+	bool shared;
+	ssize_t (*read)(struct iio_dev *, struct iio_chan_spec const *,
+			char *buf);
+	ssize_t (*write)(struct iio_dev *, struct iio_chan_spec const *,
+			const char *buf, size_t len);
+};
+
 /**
  * struct iio_chan_spec - specification of a single channel
  * @type:		What type of measurement is the channel making.
@@ -107,6 +126,9 @@ enum iio_endian {
  * @info_mask:		What information is to be exported about this channel.
  *			This includes calibbias, scale etc.
  * @event_mask:	What events can this channel produce.
+ * @ext_info:		Array of extended info attributes for this channel.
+ *			The array is NULL terminated, the last element should
+ *			have it's name field set to NULL.
  * @extend_name:	Allows labeling of channel attributes with an
  *			informative name. Note this has no effect codes etc,
  *			unlike modifiers.
@@ -141,6 +163,7 @@ struct iio_chan_spec {
 	} scan_type;
 	long			info_mask;
 	long			event_mask;
+	const struct iio_chan_spec_ext_info *ext_info;
 	char			*extend_name;
 	const char		*datasheet_name;
 	unsigned		processed_val:1;
diff --git a/drivers/staging/iio/industrialio-core.c b/drivers/staging/iio/industrialio-core.c
index e4824fe..380b927 100644
--- a/drivers/staging/iio/industrialio-core.c
+++ b/drivers/staging/iio/industrialio-core.c
@@ -144,6 +144,33 @@ static void __exit iio_exit(void)
 	bus_unregister(&iio_bus_type);
 }
 
+static ssize_t iio_read_channel_ext_info(struct device *dev,
+				     struct device_attribute *attr,
+				     char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	const struct iio_chan_spec_ext_info *ext_info;
+
+	ext_info = &this_attr->c->ext_info[this_attr->address];
+
+	return ext_info->read(indio_dev, this_attr->c, buf);
+}
+
+static ssize_t iio_write_channel_ext_info(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf,
+					 size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	const struct iio_chan_spec_ext_info *ext_info;
+
+	ext_info = &this_attr->c->ext_info[this_attr->address];
+
+	return ext_info->write(indio_dev, this_attr->c, buf, len);
+}
+
 static ssize_t iio_read_channel_info(struct device *dev,
 				     struct device_attribute *attr,
 				     char *buf)
@@ -423,6 +450,7 @@ static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
 					struct iio_chan_spec const *chan)
 {
 	int ret, i, attrcount = 0;
+	const struct iio_chan_spec_ext_info *ext_info;
 
 	if (chan->channel < 0)
 		return 0;
@@ -457,6 +485,32 @@ static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
 			goto error_ret;
 		attrcount++;
 	}
+
+	if (chan->ext_info) {
+		unsigned int i = 0;
+		for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
+			ret = __iio_add_chan_devattr(ext_info->name,
+					chan,
+					ext_info->read ?
+					    &iio_read_channel_ext_info : NULL,
+					ext_info->write ?
+					    &iio_write_channel_ext_info : NULL,
+					i,
+					ext_info->shared,
+					&indio_dev->dev,
+					&indio_dev->channel_attr_list);
+			i++;
+			if (ret == -EBUSY && ext_info->shared)
+				continue;
+
+			if (ret)
+				goto error_ret;
+
+			attrcount++;
+		}
+
+	}
+
 	ret = attrcount;
 error_ret:
 	return ret;
-- 
1.7.9

[PATCH v2 2/6] staging:iio:dac:ad5064: Convert to extended channel info attributes

[Lars-Peter Clausen]

Use extended channel info attributes for the powerdown, powerdown_mode and
powerdown_mode_available attributes.

Note that this patch moves the chip info defintions around to avoid having to use
forward declarations for the extended channel info attributes callbacks.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>

---
Changes since v1:
	* Also make powerdown_mode_available an extended info attribute
	* Reorder code to avoid forward declarations

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
---
 drivers/staging/iio/dac/ad5064.c |  188 +++++++++++++++++---------------------
 1 files changed, 82 insertions(+), 106 deletions(-)

diff --git a/drivers/staging/iio/dac/ad5064.c b/drivers/staging/iio/dac/ad5064.c
index 049a855..52fef75 100644
--- a/drivers/staging/iio/dac/ad5064.c
+++ b/drivers/staging/iio/dac/ad5064.c
@@ -86,47 +86,6 @@ enum ad5064_type {
 	ID_AD5064_1,
 };
 
-#define AD5064_CHANNEL(chan, bits) {				\
-	.type = IIO_VOLTAGE,					\
-	.indexed = 1,						\
-	.output = 1,						\
-	.channel = (chan),					\
-	.info_mask = IIO_CHAN_INFO_SCALE_SEPARATE_BIT,	\
-	.address = AD5064_ADDR_DAC(chan),			\
-	.scan_type = IIO_ST('u', (bits), 16, 20 - (bits))	\
-}
-
-static const struct ad5064_chip_info ad5064_chip_info_tbl[] = {
-	[ID_AD5024] = {
-		.shared_vref = false,
-		.channel[0] = AD5064_CHANNEL(0, 12),
-		.channel[1] = AD5064_CHANNEL(1, 12),
-		.channel[2] = AD5064_CHANNEL(2, 12),
-		.channel[3] = AD5064_CHANNEL(3, 12),
-	},
-	[ID_AD5044] = {
-		.shared_vref = false,
-		.channel[0] = AD5064_CHANNEL(0, 14),
-		.channel[1] = AD5064_CHANNEL(1, 14),
-		.channel[2] = AD5064_CHANNEL(2, 14),
-		.channel[3] = AD5064_CHANNEL(3, 14),
-	},
-	[ID_AD5064] = {
-		.shared_vref = false,
-		.channel[0] = AD5064_CHANNEL(0, 16),
-		.channel[1] = AD5064_CHANNEL(1, 16),
-		.channel[2] = AD5064_CHANNEL(2, 16),
-		.channel[3] = AD5064_CHANNEL(3, 16),
-	},
-	[ID_AD5064_1] = {
-		.shared_vref = true,
-		.channel[0] = AD5064_CHANNEL(0, 16),
-		.channel[1] = AD5064_CHANNEL(1, 16),
-		.channel[2] = AD5064_CHANNEL(2, 16),
-		.channel[3] = AD5064_CHANNEL(3, 16),
-	},
-};
-
 static int ad5064_spi_write(struct ad5064_state *st, unsigned int cmd,
 	unsigned int addr, unsigned int val, unsigned int shift)
 {
@@ -160,22 +119,25 @@ static const char ad5064_powerdown_modes[][15] = {
 	[AD5064_LDAC_PWRDN_3STATE]	= "three_state",
 };
 
-static ssize_t ad5064_read_powerdown_mode(struct device *dev,
-	struct device_attribute *attr, char *buf)
+static ssize_t ad5064_read_powerdown_mode_available(struct iio_dev *indio_dev,
+	const struct iio_chan_spec *chan, char *buf)
+{
+	return sprintf(buf, "%s %s %s\n", ad5064_powerdown_modes[1],
+		ad5064_powerdown_modes[2], ad5064_powerdown_modes[3]);
+}
+
+static ssize_t ad5064_read_powerdown_mode(struct iio_dev *indio_dev,
+	const struct iio_chan_spec *chan, char *buf)
 {
-	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
-	struct iio_dev *indio_dev = dev_get_drvdata(dev);
 	struct ad5064_state *st = iio_priv(indio_dev);
 
 	return sprintf(buf, "%s\n",
-		ad5064_powerdown_modes[st->pwr_down_mode[this_attr->address]]);
+		ad5064_powerdown_modes[st->pwr_down_mode[chan->channel]]);
 }
 
-static ssize_t ad5064_write_powerdown_mode(struct device *dev,
-	struct device_attribute *attr, const char *buf, size_t len)
+static ssize_t ad5064_write_powerdown_mode(struct iio_dev *indio_dev,
+	const struct iio_chan_spec *chan, const char *buf, size_t len)
 {
-	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
-	struct iio_dev *indio_dev = dev_get_drvdata(dev);
 	struct ad5064_state *st = iio_priv(indio_dev);
 	unsigned int mode, i;
 	int ret;
@@ -192,31 +154,26 @@ static ssize_t ad5064_write_powerdown_mode(struct device *dev,
 		return  -EINVAL;
 
 	mutex_lock(&indio_dev->mlock);
-	st->pwr_down_mode[this_attr->address] = mode;
+	st->pwr_down_mode[chan->channel] = mode;
 
-	ret = ad5064_sync_powerdown_mode(st, this_attr->address);
+	ret = ad5064_sync_powerdown_mode(st, chan->channel);
 	mutex_unlock(&indio_dev->mlock);
 
 	return ret ? ret : len;
 }
 
-static ssize_t ad5064_read_dac_powerdown(struct device *dev,
-					   struct device_attribute *attr,
-					   char *buf)
+static ssize_t ad5064_read_dac_powerdown(struct iio_dev *indio_dev,
+	const struct iio_chan_spec *chan, char *buf)
 {
-	struct iio_dev *indio_dev = dev_get_drvdata(dev);
 	struct ad5064_state *st = iio_priv(indio_dev);
-	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 
-	return sprintf(buf, "%d\n", st->pwr_down[this_attr->address]);
+	return sprintf(buf, "%d\n", st->pwr_down[chan->channel]);
 }
 
-static ssize_t ad5064_write_dac_powerdown(struct device *dev,
-	struct device_attribute *attr, const char *buf, size_t len)
+static ssize_t ad5064_write_dac_powerdown(struct iio_dev *indio_dev,
+	const struct iio_chan_spec *chan, const char *buf, size_t len)
 {
-	struct iio_dev *indio_dev = dev_get_drvdata(dev);
 	struct ad5064_state *st = iio_priv(indio_dev);
-	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 	bool pwr_down;
 	int ret;
 
@@ -225,54 +182,13 @@ static ssize_t ad5064_write_dac_powerdown(struct device *dev,
 		return ret;
 
 	mutex_lock(&indio_dev->mlock);
-	st->pwr_down[this_attr->address] = pwr_down;
+	st->pwr_down[chan->channel] = pwr_down;
 
-	ret = ad5064_sync_powerdown_mode(st, this_attr->address);
+	ret = ad5064_sync_powerdown_mode(st, chan->channel);
 	mutex_unlock(&indio_dev->mlock);
 	return ret ? ret : len;
 }
 
-static IIO_CONST_ATTR(out_voltage_powerdown_mode_available,
-			"1kohm_to_gnd 100kohm_to_gnd three_state");
-
-#define IIO_DEV_ATTR_DAC_POWERDOWN_MODE(_chan) \
-	IIO_DEVICE_ATTR(out_voltage##_chan##_powerdown_mode, \
-			S_IRUGO | S_IWUSR, \
-			ad5064_read_powerdown_mode, \
-			ad5064_write_powerdown_mode, _chan);
-
-#define IIO_DEV_ATTR_DAC_POWERDOWN(_chan)				\
-	IIO_DEVICE_ATTR(out_voltage##_chan##_powerdown,			\
-			S_IRUGO | S_IWUSR,				\
-			ad5064_read_dac_powerdown,			\
-			ad5064_write_dac_powerdown, _chan)
-
-static IIO_DEV_ATTR_DAC_POWERDOWN(0);
-static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(0);
-static IIO_DEV_ATTR_DAC_POWERDOWN(1);
-static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(1);
-static IIO_DEV_ATTR_DAC_POWERDOWN(2);
-static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(2);
-static IIO_DEV_ATTR_DAC_POWERDOWN(3);
-static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(3);
-
-static struct attribute *ad5064_attributes[] = {
-	&iio_dev_attr_out_voltage0_powerdown.dev_attr.attr,
-	&iio_dev_attr_out_voltage1_powerdown.dev_attr.attr,
-	&iio_dev_attr_out_voltage2_powerdown.dev_attr.attr,
-	&iio_dev_attr_out_voltage3_powerdown.dev_attr.attr,
-	&iio_dev_attr_out_voltage0_powerdown_mode.dev_attr.attr,
-	&iio_dev_attr_out_voltage1_powerdown_mode.dev_attr.attr,
-	&iio_dev_attr_out_voltage2_powerdown_mode.dev_attr.attr,
-	&iio_dev_attr_out_voltage3_powerdown_mode.dev_attr.attr,
-	&iio_const_attr_out_voltage_powerdown_mode_available.dev_attr.attr,
-	NULL,
-};
-
-static const struct attribute_group ad5064_attribute_group = {
-	.attrs = ad5064_attributes,
-};
-
 static int ad5064_read_raw(struct iio_dev *indio_dev,
 			   struct iio_chan_spec const *chan,
 			   int *val,
@@ -331,10 +247,70 @@ static int ad5064_write_raw(struct iio_dev *indio_dev,
 static const struct iio_info ad5064_info = {
 	.read_raw = ad5064_read_raw,
 	.write_raw = ad5064_write_raw,
-	.attrs = &ad5064_attribute_group,
 	.driver_module = THIS_MODULE,
 };
 
+static struct iio_chan_spec_ext_info ad5064_ext_info[] = {
+	{
+		.name = "powerdown",
+		.read = ad5064_read_dac_powerdown,
+		.write = ad5064_write_dac_powerdown,
+	},
+	{
+		.name = "powerdown_mode",
+		.read = ad5064_read_powerdown_mode,
+		.write = ad5064_write_powerdown_mode,
+	},
+	{
+		.name = "powerdown_mode_available",
+		.shared = true,
+		.read = ad5064_read_powerdown_mode_available,
+	},
+	{ },
+};
+
+#define AD5064_CHANNEL(chan, bits) {				\
+	.type = IIO_VOLTAGE,					\
+	.indexed = 1,						\
+	.output = 1,						\
+	.channel = (chan),					\
+	.info_mask = IIO_CHAN_INFO_SCALE_SEPARATE_BIT,	\
+	.address = AD5064_ADDR_DAC(chan),			\
+	.scan_type = IIO_ST('u', (bits), 16, 20 - (bits)),	\
+	.ext_info = ad5064_ext_info,				\
+}
+
+static const struct ad5064_chip_info ad5064_chip_info_tbl[] = {
+	[ID_AD5024] = {
+		.shared_vref = false,
+		.channel[0] = AD5064_CHANNEL(0, 12),
+		.channel[1] = AD5064_CHANNEL(1, 12),
+		.channel[2] = AD5064_CHANNEL(2, 12),
+		.channel[3] = AD5064_CHANNEL(3, 12),
+	},
+	[ID_AD5044] = {
+		.shared_vref = false,
+		.channel[0] = AD5064_CHANNEL(0, 14),
+		.channel[1] = AD5064_CHANNEL(1, 14),
+		.channel[2] = AD5064_CHANNEL(2, 14),
+		.channel[3] = AD5064_CHANNEL(3, 14),
+	},
+	[ID_AD5064] = {
+		.shared_vref = false,
+		.channel[0] = AD5064_CHANNEL(0, 16),
+		.channel[1] = AD5064_CHANNEL(1, 16),
+		.channel[2] = AD5064_CHANNEL(2, 16),
+		.channel[3] = AD5064_CHANNEL(3, 16),
+	},
+	[ID_AD5064_1] = {
+		.shared_vref = true,
+		.channel[0] = AD5064_CHANNEL(0, 16),
+		.channel[1] = AD5064_CHANNEL(1, 16),
+		.channel[2] = AD5064_CHANNEL(2, 16),
+		.channel[3] = AD5064_CHANNEL(3, 16),
+	},
+};
+
 static inline unsigned int ad5064_num_vref(struct ad5064_state *st)
 {
 	return st->chip_info->shared_vref ? 1 : AD5064_DAC_CHANNELS;
-- 
1.7.9

[PATCH v2 3/6] staging:iio:dac:ad5064: Prepare driver for the addition of chip variants

[Lars-Peter Clausen]

Prepare the driver for the addition of chip variants with a different number of
channels. This is done by not hard-coding the number of channels, but instead
add a field to the chip info struct holding the number of channels. Also do not
embed the channel specs into the chip info, but rather store them independently.
This allows sharing the same channel spec between different chip infos.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
---
 drivers/staging/iio/dac/ad5064.c |   61 +++++++++++++++++++++-----------------
 1 files changed, 34 insertions(+), 27 deletions(-)

diff --git a/drivers/staging/iio/dac/ad5064.c b/drivers/staging/iio/dac/ad5064.c
index 52fef75..40db679 100644
--- a/drivers/staging/iio/dac/ad5064.c
+++ b/drivers/staging/iio/dac/ad5064.c
@@ -19,7 +19,8 @@
 #include "../sysfs.h"
 #include "dac.h"
 
-#define AD5064_DAC_CHANNELS			4
+#define AD5064_MAX_DAC_CHANNELS			4
+#define AD5064_MAX_VREFS			4
 
 #define AD5064_ADDR(x)				((x) << 20)
 #define AD5064_CMD(x)				((x) << 24)
@@ -46,11 +47,13 @@
  * struct ad5064_chip_info - chip specific information
  * @shared_vref:	whether the vref supply is shared between channels
  * @channel:		channel specification
-*/
+ * @num_channels:	number of channels
+ */
 
 struct ad5064_chip_info {
 	bool shared_vref;
-	struct iio_chan_spec channel[AD5064_DAC_CHANNELS];
+	const struct iio_chan_spec *channels;
+	unsigned int num_channels;
 };
 
 /**
@@ -67,10 +70,10 @@ struct ad5064_chip_info {
 struct ad5064_state {
 	struct spi_device		*spi;
 	const struct ad5064_chip_info	*chip_info;
-	struct regulator_bulk_data	vref_reg[AD5064_DAC_CHANNELS];
-	bool				pwr_down[AD5064_DAC_CHANNELS];
-	u8				pwr_down_mode[AD5064_DAC_CHANNELS];
-	unsigned int			dac_cache[AD5064_DAC_CHANNELS];
+	struct regulator_bulk_data	vref_reg[AD5064_MAX_VREFS];
+	bool				pwr_down[AD5064_MAX_DAC_CHANNELS];
+	u8				pwr_down_mode[AD5064_MAX_DAC_CHANNELS];
+	unsigned int			dac_cache[AD5064_MAX_DAC_CHANNELS];
 
 	/*
 	 * DMA (thus cache coherency maintenance) requires the
@@ -280,40 +283,44 @@ static struct iio_chan_spec_ext_info ad5064_ext_info[] = {
 	.ext_info = ad5064_ext_info,				\
 }
 
+#define DECLARE_AD5064_CHANNELS(name, bits) \
+const struct iio_chan_spec name[] = { \
+	AD5064_CHANNEL(0, bits), \
+	AD5064_CHANNEL(1, bits), \
+	AD5064_CHANNEL(2, bits), \
+	AD5064_CHANNEL(3, bits), \
+}
+
+static DECLARE_AD5064_CHANNELS(ad5024_channels, 12);
+static DECLARE_AD5064_CHANNELS(ad5044_channels, 14);
+static DECLARE_AD5064_CHANNELS(ad5064_channels, 16);
+
 static const struct ad5064_chip_info ad5064_chip_info_tbl[] = {
 	[ID_AD5024] = {
 		.shared_vref = false,
-		.channel[0] = AD5064_CHANNEL(0, 12),
-		.channel[1] = AD5064_CHANNEL(1, 12),
-		.channel[2] = AD5064_CHANNEL(2, 12),
-		.channel[3] = AD5064_CHANNEL(3, 12),
+		.channels = ad5024_channels,
+		.num_channels = 4,
 	},
 	[ID_AD5044] = {
 		.shared_vref = false,
-		.channel[0] = AD5064_CHANNEL(0, 14),
-		.channel[1] = AD5064_CHANNEL(1, 14),
-		.channel[2] = AD5064_CHANNEL(2, 14),
-		.channel[3] = AD5064_CHANNEL(3, 14),
+		.channels = ad5044_channels,
+		.num_channels = 4,
 	},
 	[ID_AD5064] = {
 		.shared_vref = false,
-		.channel[0] = AD5064_CHANNEL(0, 16),
-		.channel[1] = AD5064_CHANNEL(1, 16),
-		.channel[2] = AD5064_CHANNEL(2, 16),
-		.channel[3] = AD5064_CHANNEL(3, 16),
+		.channels = ad5064_channels,
+		.num_channels = 4,
 	},
 	[ID_AD5064_1] = {
 		.shared_vref = true,
-		.channel[0] = AD5064_CHANNEL(0, 16),
-		.channel[1] = AD5064_CHANNEL(1, 16),
-		.channel[2] = AD5064_CHANNEL(2, 16),
-		.channel[3] = AD5064_CHANNEL(3, 16),
+		.channels = ad5064_channels,
+		.num_channels = 4,
 	},
 };
 
 static inline unsigned int ad5064_num_vref(struct ad5064_state *st)
 {
-	return st->chip_info->shared_vref ? 1 : AD5064_DAC_CHANNELS;
+	return st->chip_info->shared_vref ? 1 : st->chip_info->num_channels;
 }
 
 static const char * const ad5064_vref_names[] = {
@@ -359,7 +366,7 @@ static int __devinit ad5064_probe(struct spi_device *spi)
 	if (ret)
 		goto error_free_reg;
 
-	for (i = 0; i < AD5064_DAC_CHANNELS; ++i) {
+	for (i = 0; i < st->chip_info->num_channels; ++i) {
 		st->pwr_down_mode[i] = AD5064_LDAC_PWRDN_1K;
 		st->dac_cache[i] = 0x8000;
 	}
@@ -368,8 +375,8 @@ static int __devinit ad5064_probe(struct spi_device *spi)
 	indio_dev->name = spi_get_device_id(spi)->name;
 	indio_dev->info = &ad5064_info;
 	indio_dev->modes = INDIO_DIRECT_MODE;
-	indio_dev->channels = st->chip_info->channel;
-	indio_dev->num_channels = AD5064_DAC_CHANNELS;
+	indio_dev->channels = st->chip_info->channels;
+	indio_dev->num_channels = st->chip_info->num_channels;
 
 	ret = iio_device_register(indio_dev);
 	if (ret)
-- 
1.7.9

[PATCH v2 4/6] staging:iio:dac:ad5064: Add AD5025/AD5045/AD5065 support

[Lars-Peter Clausen]

The AD5025/AD5045/AD5065 are identical to the AD5024/AD5044/AD5064 excpet that
they have 2 instead of 4 DAC channels.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
---
 drivers/staging/iio/dac/Kconfig  |    6 +++---
 drivers/staging/iio/dac/ad5064.c |   26 ++++++++++++++++++++++++--
 2 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/drivers/staging/iio/dac/Kconfig b/drivers/staging/iio/dac/Kconfig
index 13e2797..66b2504 100644
--- a/drivers/staging/iio/dac/Kconfig
+++ b/drivers/staging/iio/dac/Kconfig
@@ -4,11 +4,11 @@
 menu "Digital to analog converters"
 
 config AD5064
-	tristate "Analog Devices AD5064/64-1/44/24 DAC driver"
+	tristate "Analog Devices AD5064/64-1/65/44/45/24/25 DAC driver"
 	depends on SPI
 	help
-	  Say yes here to build support for Analog Devices AD5064, AD5064-1,
-	  AD5044, AD5024 Digital to Analog Converter.
+	  Say yes here to build support for Analog Devices AD5024, AD5025, AD5044,
+	  AD5045, AD5064, AD5064-1, AD5065 Digital to Analog Converter.
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called ad5064.
diff --git a/drivers/staging/iio/dac/ad5064.c b/drivers/staging/iio/dac/ad5064.c
index 40db679..865e81f 100644
--- a/drivers/staging/iio/dac/ad5064.c
+++ b/drivers/staging/iio/dac/ad5064.c
@@ -1,5 +1,6 @@
 /*
- * AD5064, AD5064-1, AD5044, AD5024 Digital to analog converters  driver
+ * AD5024, AD5025, AD5044, AD5045, AD5064, AD5064-1 Digital to analog converters
+ * driver
  *
  * Copyright 2011 Analog Devices Inc.
  *
@@ -84,9 +85,12 @@ struct ad5064_state {
 
 enum ad5064_type {
 	ID_AD5024,
+	ID_AD5025,
 	ID_AD5044,
+	ID_AD5045,
 	ID_AD5064,
 	ID_AD5064_1,
+	ID_AD5065,
 };
 
 static int ad5064_spi_write(struct ad5064_state *st, unsigned int cmd,
@@ -301,11 +305,21 @@ static const struct ad5064_chip_info ad5064_chip_info_tbl[] = {
 		.channels = ad5024_channels,
 		.num_channels = 4,
 	},
+	[ID_AD5025] = {
+		.shared_vref = false,
+		.channels = ad5024_channels,
+		.num_channels = 2,
+	},
 	[ID_AD5044] = {
 		.shared_vref = false,
 		.channels = ad5044_channels,
 		.num_channels = 4,
 	},
+	[ID_AD5045] = {
+		.shared_vref = false,
+		.channels = ad5044_channels,
+		.num_channels = 2,
+	},
 	[ID_AD5064] = {
 		.shared_vref = false,
 		.channels = ad5064_channels,
@@ -316,6 +330,11 @@ static const struct ad5064_chip_info ad5064_chip_info_tbl[] = {
 		.channels = ad5064_channels,
 		.num_channels = 4,
 	},
+	[ID_AD5065] = {
+		.shared_vref = false,
+		.channels = ad5064_channels,
+		.num_channels = 2,
+	},
 };
 
 static inline unsigned int ad5064_num_vref(struct ad5064_state *st)
@@ -412,9 +431,12 @@ static int __devexit ad5064_remove(struct spi_device *spi)
 
 static const struct spi_device_id ad5064_id[] = {
 	{"ad5024", ID_AD5024},
+	{"ad5025", ID_AD5025},
 	{"ad5044", ID_AD5044},
+	{"ad5045", ID_AD5045},
 	{"ad5064", ID_AD5064},
 	{"ad5064-1", ID_AD5064_1},
+	{"ad5065", ID_AD5065},
 	{}
 };
 MODULE_DEVICE_TABLE(spi, ad5064_id);
@@ -431,5 +453,5 @@ static struct spi_driver ad5064_driver = {
 module_spi_driver(ad5064_driver);
 
 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
-MODULE_DESCRIPTION("Analog Devices AD5064/64-1/44/24 DAC");
+MODULE_DESCRIPTION("Analog Devices AD5024/25/44/45/64/64-1/65 DAC");
 MODULE_LICENSE("GPL v2");
-- 
1.7.9

[PATCH v2 5/6] staging:iio:dac:ad5064: Add AD5628/AD5648/AD5668 support

[Lars-Peter Clausen]

The AD5628/AD5648/AD5668 are similar to the AD5024/AD5044/AD5064. The difference
being that they have an internal reference voltage and 8 instead of 4 DAC
channels.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
---
 drivers/staging/iio/dac/Kconfig  |    5 +-
 drivers/staging/iio/dac/ad5064.c |  122 ++++++++++++++++++++++++++++++++------
 2 files changed, 107 insertions(+), 20 deletions(-)

diff --git a/drivers/staging/iio/dac/Kconfig b/drivers/staging/iio/dac/Kconfig
index 66b2504..ab8516d 100644
--- a/drivers/staging/iio/dac/Kconfig
+++ b/drivers/staging/iio/dac/Kconfig
@@ -4,11 +4,12 @@
 menu "Digital to analog converters"
 
 config AD5064
-	tristate "Analog Devices AD5064/64-1/65/44/45/24/25 DAC driver"
+	tristate "Analog Devices AD5064/64-1/65/44/45/24/25, AD5628/48/68 DAC driver"
 	depends on SPI
 	help
 	  Say yes here to build support for Analog Devices AD5024, AD5025, AD5044,
-	  AD5045, AD5064, AD5064-1, AD5065 Digital to Analog Converter.
+	  AD5045, AD5064, AD5064-1, AD5065, AD5628, AD5648, AD5668 Digital to Analog
+	  Converter.
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called ad5064.
diff --git a/drivers/staging/iio/dac/ad5064.c b/drivers/staging/iio/dac/ad5064.c
index 865e81f..6dab064 100644
--- a/drivers/staging/iio/dac/ad5064.c
+++ b/drivers/staging/iio/dac/ad5064.c
@@ -1,6 +1,6 @@
 /*
- * AD5024, AD5025, AD5044, AD5045, AD5064, AD5064-1 Digital to analog converters
- * driver
+ * AD5024, AD5025, AD5044, AD5045, AD5064, AD5064-1, AD5065, AD5628, AD5648,
+ * AD5668 Digital to analog converters driver
  *
  * Copyright 2011 Analog Devices Inc.
  *
@@ -20,7 +20,7 @@
 #include "../sysfs.h"
 #include "dac.h"
 
-#define AD5064_MAX_DAC_CHANNELS			4
+#define AD5064_MAX_DAC_CHANNELS			8
 #define AD5064_MAX_VREFS			4
 
 #define AD5064_ADDR(x)				((x) << 20)
@@ -37,7 +37,10 @@
 #define AD5064_CMD_CLEAR			0x5
 #define AD5064_CMD_LDAC_MASK			0x6
 #define AD5064_CMD_RESET			0x7
-#define AD5064_CMD_DAISY_CHAIN_ENABLE		0x8
+#define AD5064_CMD_CONFIG			0x8
+
+#define AD5064_CONFIG_DAISY_CHAIN_ENABLE	BIT(1)
+#define AD5064_CONFIG_INT_VREF_ENABLE		BIT(0)
 
 #define AD5064_LDAC_PWRDN_NONE			0x0
 #define AD5064_LDAC_PWRDN_1K			0x1
@@ -47,12 +50,15 @@
 /**
  * struct ad5064_chip_info - chip specific information
  * @shared_vref:	whether the vref supply is shared between channels
+ * @internal_vref:	internal reference voltage. 0 if the chip has no internal
+ *			vref.
  * @channel:		channel specification
  * @num_channels:	number of channels
  */
 
 struct ad5064_chip_info {
 	bool shared_vref;
+	unsigned long internal_vref;
 	const struct iio_chan_spec *channels;
 	unsigned int num_channels;
 };
@@ -65,6 +71,8 @@ struct ad5064_chip_info {
  * @pwr_down:		whether channel is powered down
  * @pwr_down_mode:	channel's current power down mode
  * @dac_cache:		current DAC raw value (chip does not support readback)
+ * @use_internal_vref:	set to true if the internal reference voltage should be
+ *			used.
  * @data:		spi transfer buffers
  */
 
@@ -75,6 +83,7 @@ struct ad5064_state {
 	bool				pwr_down[AD5064_MAX_DAC_CHANNELS];
 	u8				pwr_down_mode[AD5064_MAX_DAC_CHANNELS];
 	unsigned int			dac_cache[AD5064_MAX_DAC_CHANNELS];
+	bool				use_internal_vref;
 
 	/*
 	 * DMA (thus cache coherency maintenance) requires the
@@ -91,6 +100,12 @@ enum ad5064_type {
 	ID_AD5064,
 	ID_AD5064_1,
 	ID_AD5065,
+	ID_AD5628_1,
+	ID_AD5628_2,
+	ID_AD5648_1,
+	ID_AD5648_2,
+	ID_AD5668_1,
+	ID_AD5668_2,
 };
 
 static int ad5064_spi_write(struct ad5064_state *st, unsigned int cmd,
@@ -196,6 +211,18 @@ static ssize_t ad5064_write_dac_powerdown(struct iio_dev *indio_dev,
 	return ret ? ret : len;
 }
 
+static int ad5064_get_vref(struct ad5064_state *st,
+	struct iio_chan_spec const *chan)
+{
+	unsigned int i;
+
+	if (st->use_internal_vref)
+		return st->chip_info->internal_vref;
+
+	i = st->chip_info->shared_vref ? 0 : chan->channel;
+	return regulator_get_voltage(st->vref_reg[i].consumer);
+}
+
 static int ad5064_read_raw(struct iio_dev *indio_dev,
 			   struct iio_chan_spec const *chan,
 			   int *val,
@@ -203,7 +230,6 @@ static int ad5064_read_raw(struct iio_dev *indio_dev,
 			   long m)
 {
 	struct ad5064_state *st = iio_priv(indio_dev);
-	unsigned int vref;
 	int scale_uv;
 
 	switch (m) {
@@ -211,8 +237,7 @@ static int ad5064_read_raw(struct iio_dev *indio_dev,
 		*val = st->dac_cache[chan->channel];
 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_SCALE:
-		vref = st->chip_info->shared_vref ? 0 : chan->channel;
-		scale_uv = regulator_get_voltage(st->vref_reg[vref].consumer);
+		scale_uv = ad5064_get_vref(st, chan);
 		if (scale_uv < 0)
 			return scale_uv;
 
@@ -293,6 +318,10 @@ const struct iio_chan_spec name[] = { \
 	AD5064_CHANNEL(1, bits), \
 	AD5064_CHANNEL(2, bits), \
 	AD5064_CHANNEL(3, bits), \
+	AD5064_CHANNEL(4, bits), \
+	AD5064_CHANNEL(5, bits), \
+	AD5064_CHANNEL(6, bits), \
+	AD5064_CHANNEL(7, bits), \
 }
 
 static DECLARE_AD5064_CHANNELS(ad5024_channels, 12);
@@ -335,6 +364,42 @@ static const struct ad5064_chip_info ad5064_chip_info_tbl[] = {
 		.channels = ad5064_channels,
 		.num_channels = 2,
 	},
+	[ID_AD5628_1] = {
+		.shared_vref = true,
+		.internal_vref = 2500000,
+		.channels = ad5024_channels,
+		.num_channels = 8,
+	},
+	[ID_AD5628_2] = {
+		.shared_vref = true,
+		.internal_vref = 5000000,
+		.channels = ad5024_channels,
+		.num_channels = 8,
+	},
+	[ID_AD5648_1] = {
+		.shared_vref = true,
+		.internal_vref = 2500000,
+		.channels = ad5044_channels,
+		.num_channels = 8,
+	},
+	[ID_AD5648_2] = {
+		.shared_vref = true,
+		.internal_vref = 5000000,
+		.channels = ad5044_channels,
+		.num_channels = 8,
+	},
+	[ID_AD5668_1] = {
+		.shared_vref = true,
+		.internal_vref = 2500000,
+		.channels = ad5064_channels,
+		.num_channels = 8,
+	},
+	[ID_AD5668_2] = {
+		.shared_vref = true,
+		.internal_vref = 5000000,
+		.channels = ad5064_channels,
+		.num_channels = 8,
+	},
 };
 
 static inline unsigned int ad5064_num_vref(struct ad5064_state *st)
@@ -378,12 +443,22 @@ static int __devinit ad5064_probe(struct spi_device *spi)
 
 	ret = regulator_bulk_get(&st->spi->dev, ad5064_num_vref(st),
 		st->vref_reg);
-	if (ret)
-		goto error_free;
-
-	ret = regulator_bulk_enable(ad5064_num_vref(st), st->vref_reg);
-	if (ret)
-		goto error_free_reg;
+	if (ret) {
+		if (!st->chip_info->internal_vref)
+			goto error_free;
+		st->use_internal_vref = true;
+		ret = ad5064_spi_write(st, AD5064_CMD_CONFIG, 0,
+			AD5064_CONFIG_INT_VREF_ENABLE, 0);
+		if (ret) {
+			dev_err(&spi->dev, "Failed to enable internal vref: %d\n",
+				ret);
+			goto error_free;
+		}
+	} else {
+		ret = regulator_bulk_enable(ad5064_num_vref(st), st->vref_reg);
+		if (ret)
+			goto error_free_reg;
+	}
 
 	for (i = 0; i < st->chip_info->num_channels; ++i) {
 		st->pwr_down_mode[i] = AD5064_LDAC_PWRDN_1K;
@@ -404,9 +479,11 @@ static int __devinit ad5064_probe(struct spi_device *spi)
 	return 0;
 
 error_disable_reg:
-	regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg);
+	if (!st->use_internal_vref)
+		regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg);
 error_free_reg:
-	regulator_bulk_free(ad5064_num_vref(st), st->vref_reg);
+	if (!st->use_internal_vref)
+		regulator_bulk_free(ad5064_num_vref(st), st->vref_reg);
 error_free:
 	iio_free_device(indio_dev);
 
@@ -421,8 +498,10 @@ static int __devexit ad5064_remove(struct spi_device *spi)
 
 	iio_device_unregister(indio_dev);
 
-	regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg);
-	regulator_bulk_free(ad5064_num_vref(st), st->vref_reg);
+	if (!st->use_internal_vref) {
+		regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg);
+		regulator_bulk_free(ad5064_num_vref(st), st->vref_reg);
+	}
 
 	iio_free_device(indio_dev);
 
@@ -437,6 +516,13 @@ static const struct spi_device_id ad5064_id[] = {
 	{"ad5064", ID_AD5064},
 	{"ad5064-1", ID_AD5064_1},
 	{"ad5065", ID_AD5065},
+	{"ad5628-1", ID_AD5628_1},
+	{"ad5628-2", ID_AD5628_2},
+	{"ad5648-1", ID_AD5648_1},
+	{"ad5648-2", ID_AD5648_2},
+	{"ad5668-1", ID_AD5668_1},
+	{"ad5668-2", ID_AD5668_2},
+	{"ad5668-3", ID_AD5668_2}, /* similar enough to ad5668-2 */
 	{}
 };
 MODULE_DEVICE_TABLE(spi, ad5064_id);
@@ -453,5 +539,5 @@ static struct spi_driver ad5064_driver = {
 module_spi_driver(ad5064_driver);
 
 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
-MODULE_DESCRIPTION("Analog Devices AD5024/25/44/45/64/64-1/65 DAC");
+MODULE_DESCRIPTION("Analog Devices AD5024/25/44/45/64/64-1/65, AD5628/48/68 DAC");
 MODULE_LICENSE("GPL v2");
-- 
1.7.9

[PATCH v2 6/6] staging:iio:dac:ad5064: Add AD5666 support

[Lars-Peter Clausen]

The AD5666 is identical to the ad5064-1, except has a internal reference
voltage.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
---
 drivers/staging/iio/dac/Kconfig  |    6 +++---
 drivers/staging/iio/dac/ad5064.c |   20 ++++++++++++++++++--
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/drivers/staging/iio/dac/Kconfig b/drivers/staging/iio/dac/Kconfig
index ab8516d..a57803a 100644
--- a/drivers/staging/iio/dac/Kconfig
+++ b/drivers/staging/iio/dac/Kconfig
@@ -4,12 +4,12 @@
 menu "Digital to analog converters"
 
 config AD5064
-	tristate "Analog Devices AD5064/64-1/65/44/45/24/25, AD5628/48/68 DAC driver"
+	tristate "Analog Devices AD5064/64-1/65/44/45/24/25, AD5628/48/66/68 DAC driver"
 	depends on SPI
 	help
 	  Say yes here to build support for Analog Devices AD5024, AD5025, AD5044,
-	  AD5045, AD5064, AD5064-1, AD5065, AD5628, AD5648, AD5668 Digital to Analog
-	  Converter.
+	  AD5045, AD5064, AD5064-1, AD5065, AD5628, AD5648, AD5666, AD5668 Digital
+	  to Analog Converter.
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called ad5064.
diff --git a/drivers/staging/iio/dac/ad5064.c b/drivers/staging/iio/dac/ad5064.c
index 6dab064..06b1627 100644
--- a/drivers/staging/iio/dac/ad5064.c
+++ b/drivers/staging/iio/dac/ad5064.c
@@ -1,6 +1,6 @@
 /*
  * AD5024, AD5025, AD5044, AD5045, AD5064, AD5064-1, AD5065, AD5628, AD5648,
- * AD5668 Digital to analog converters driver
+ * AD5666, AD5668 Digital to analog converters driver
  *
  * Copyright 2011 Analog Devices Inc.
  *
@@ -104,6 +104,8 @@ enum ad5064_type {
 	ID_AD5628_2,
 	ID_AD5648_1,
 	ID_AD5648_2,
+	ID_AD5666_1,
+	ID_AD5666_2,
 	ID_AD5668_1,
 	ID_AD5668_2,
 };
@@ -388,6 +390,18 @@ static const struct ad5064_chip_info ad5064_chip_info_tbl[] = {
 		.channels = ad5044_channels,
 		.num_channels = 8,
 	},
+	[ID_AD5666_1] = {
+		.shared_vref = true,
+		.internal_vref = 2500000,
+		.channels = ad5064_channels,
+		.num_channels = 4,
+	},
+	[ID_AD5666_2] = {
+		.shared_vref = true,
+		.internal_vref = 5000000,
+		.channels = ad5064_channels,
+		.num_channels = 4,
+	},
 	[ID_AD5668_1] = {
 		.shared_vref = true,
 		.internal_vref = 2500000,
@@ -520,6 +534,8 @@ static const struct spi_device_id ad5064_id[] = {
 	{"ad5628-2", ID_AD5628_2},
 	{"ad5648-1", ID_AD5648_1},
 	{"ad5648-2", ID_AD5648_2},
+	{"ad5666-1", ID_AD5666_1},
+	{"ad5666-2", ID_AD5666_2},
 	{"ad5668-1", ID_AD5668_1},
 	{"ad5668-2", ID_AD5668_2},
 	{"ad5668-3", ID_AD5668_2}, /* similar enough to ad5668-2 */
@@ -539,5 +555,5 @@ static struct spi_driver ad5064_driver = {
 module_spi_driver(ad5064_driver);
 
 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
-MODULE_DESCRIPTION("Analog Devices AD5024/25/44/45/64/64-1/65, AD5628/48/68 DAC");
+MODULE_DESCRIPTION("Analog Devices AD5024/25/44/45/64/64-1/65, AD5628/48/66/68 DAC");
 MODULE_LICENSE("GPL v2");
-- 
1.7.9

Re: [PATCH v2 3/6] staging:iio:dac:ad5064: Prepare driver for the addition of chip variants

[Jonathan Cameron]

On 2/20/2012 11:55 AM, Lars-Peter Clausen wrote:
> Prepare the driver for the addition of chip variants with a different number of
> channels. This is done by not hard-coding the number of channels, but instead
> add a field to the chip info struct holding the number of channels. Also do not
> embed the channel specs into the chip info, but rather store them independently.
> This allows sharing the same channel spec between different chip infos.
>
> Signed-off-by: Lars-Peter Clausen<lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
> ---
>   drivers/staging/iio/dac/ad5064.c |   61 +++++++++++++++++++++-----------------
>   1 files changed, 34 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/staging/iio/dac/ad5064.c b/drivers/staging/iio/dac/ad5064.c
> index 52fef75..40db679 100644
> --- a/drivers/staging/iio/dac/ad5064.c
> +++ b/drivers/staging/iio/dac/ad5064.c
> @@ -19,7 +19,8 @@
>   #include "../sysfs.h"
>   #include "dac.h"
>
> -#define AD5064_DAC_CHANNELS			4
> +#define AD5064_MAX_DAC_CHANNELS			4
> +#define AD5064_MAX_VREFS			4
>
>   #define AD5064_ADDR(x)				((x)<<  20)
>   #define AD5064_CMD(x)				((x)<<  24)
> @@ -46,11 +47,13 @@
>    * struct ad5064_chip_info - chip specific information
>    * @shared_vref:	whether the vref supply is shared between channels
>    * @channel:		channel specification
> -*/
> + * @num_channels:	number of channels
> + */
>
>   struct ad5064_chip_info {
>   	bool shared_vref;
> -	struct iio_chan_spec channel[AD5064_DAC_CHANNELS];
> +	const struct iio_chan_spec *channels;
> +	unsigned int num_channels;
>   };
>
>   /**
> @@ -67,10 +70,10 @@ struct ad5064_chip_info {
>   struct ad5064_state {
>   	struct spi_device		*spi;
>   	const struct ad5064_chip_info	*chip_info;
> -	struct regulator_bulk_data	vref_reg[AD5064_DAC_CHANNELS];
> -	bool				pwr_down[AD5064_DAC_CHANNELS];
> -	u8				pwr_down_mode[AD5064_DAC_CHANNELS];
> -	unsigned int			dac_cache[AD5064_DAC_CHANNELS];
> +	struct regulator_bulk_data	vref_reg[AD5064_MAX_VREFS];
> +	bool				pwr_down[AD5064_MAX_DAC_CHANNELS];
> +	u8				pwr_down_mode[AD5064_MAX_DAC_CHANNELS];
> +	unsigned int			dac_cache[AD5064_MAX_DAC_CHANNELS];
>
>   	/*
>   	 * DMA (thus cache coherency maintenance) requires the
> @@ -280,40 +283,44 @@ static struct iio_chan_spec_ext_info ad5064_ext_info[] = {
>   	.ext_info = ad5064_ext_info,				\
>   }
>
> +#define DECLARE_AD5064_CHANNELS(name, bits) \
> +const struct iio_chan_spec name[] = { \
> +	AD5064_CHANNEL(0, bits), \
> +	AD5064_CHANNEL(1, bits), \
> +	AD5064_CHANNEL(2, bits), \
> +	AD5064_CHANNEL(3, bits), \
> +}
> +
> +static DECLARE_AD5064_CHANNELS(ad5024_channels, 12);
> +static DECLARE_AD5064_CHANNELS(ad5044_channels, 14);
> +static DECLARE_AD5064_CHANNELS(ad5064_channels, 16);
> +
>   static const struct ad5064_chip_info ad5064_chip_info_tbl[] = {
>   	[ID_AD5024] = {
>   		.shared_vref = false,
> -		.channel[0] = AD5064_CHANNEL(0, 12),
> -		.channel[1] = AD5064_CHANNEL(1, 12),
> -		.channel[2] = AD5064_CHANNEL(2, 12),
> -		.channel[3] = AD5064_CHANNEL(3, 12),
> +		.channels = ad5024_channels,
> +		.num_channels = 4,
>   	},
>   	[ID_AD5044] = {
>   		.shared_vref = false,
> -		.channel[0] = AD5064_CHANNEL(0, 14),
> -		.channel[1] = AD5064_CHANNEL(1, 14),
> -		.channel[2] = AD5064_CHANNEL(2, 14),
> -		.channel[3] = AD5064_CHANNEL(3, 14),
> +		.channels = ad5044_channels,
> +		.num_channels = 4,
>   	},
>   	[ID_AD5064] = {
>   		.shared_vref = false,
> -		.channel[0] = AD5064_CHANNEL(0, 16),
> -		.channel[1] = AD5064_CHANNEL(1, 16),
> -		.channel[2] = AD5064_CHANNEL(2, 16),
> -		.channel[3] = AD5064_CHANNEL(3, 16),
> +		.channels = ad5064_channels,
> +		.num_channels = 4,
>   	},
>   	[ID_AD5064_1] = {
>   		.shared_vref = true,
> -		.channel[0] = AD5064_CHANNEL(0, 16),
> -		.channel[1] = AD5064_CHANNEL(1, 16),
> -		.channel[2] = AD5064_CHANNEL(2, 16),
> -		.channel[3] = AD5064_CHANNEL(3, 16),
> +		.channels = ad5064_channels,
> +		.num_channels = 4,
>   	},
>   };
>
>   static inline unsigned int ad5064_num_vref(struct ad5064_state *st)
>   {
> -	return st->chip_info->shared_vref ? 1 : AD5064_DAC_CHANNELS;
> +	return st->chip_info->shared_vref ? 1 : st->chip_info->num_channels;
>   }
>
>   static const char * const ad5064_vref_names[] = {
> @@ -359,7 +366,7 @@ static int __devinit ad5064_probe(struct spi_device *spi)
>   	if (ret)
>   		goto error_free_reg;
>
> -	for (i = 0; i<  AD5064_DAC_CHANNELS; ++i) {
> +	for (i = 0; i<  st->chip_info->num_channels; ++i) {
>   		st->pwr_down_mode[i] = AD5064_LDAC_PWRDN_1K;
>   		st->dac_cache[i] = 0x8000;
>   	}
> @@ -368,8 +375,8 @@ static int __devinit ad5064_probe(struct spi_device *spi)
>   	indio_dev->name = spi_get_device_id(spi)->name;
>   	indio_dev->info =&ad5064_info;
>   	indio_dev->modes = INDIO_DIRECT_MODE;
> -	indio_dev->channels = st->chip_info->channel;
> -	indio_dev->num_channels = AD5064_DAC_CHANNELS;
> +	indio_dev->channels = st->chip_info->channels;
> +	indio_dev->num_channels = st->chip_info->num_channels;
>
>   	ret = iio_device_register(indio_dev);
>   	if (ret)

Re: [PATCH v2 4/6] staging:iio:dac:ad5064: Add AD5025/AD5045/AD5065 support

[Jonathan Cameron]

On 2/20/2012 11:55 AM, Lars-Peter Clausen wrote:
> The AD5025/AD5045/AD5065 are identical to the AD5024/AD5044/AD5064 excpet that
except
> they have 2 instead of 4 DAC channels.
>
> Signed-off-by: Lars-Peter Clausen<lars@metafoo.de>
> Acked-by: Jonathan Cameron<jic23@kernel.org>
> ---
>   drivers/staging/iio/dac/Kconfig  |    6 +++---
>   drivers/staging/iio/dac/ad5064.c |   26 ++++++++++++++++++++++++--
>   2 files changed, 27 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/staging/iio/dac/Kconfig b/drivers/staging/iio/dac/Kconfig
> index 13e2797..66b2504 100644
> --- a/drivers/staging/iio/dac/Kconfig
> +++ b/drivers/staging/iio/dac/Kconfig
> @@ -4,11 +4,11 @@
>   menu "Digital to analog converters"
>
>   config AD5064
> -	tristate "Analog Devices AD5064/64-1/44/24 DAC driver"
> +	tristate "Analog Devices AD5064/64-1/65/44/45/24/25 DAC driver"
>   	depends on SPI
>   	help
> -	  Say yes here to build support for Analog Devices AD5064, AD5064-1,
> -	  AD5044, AD5024 Digital to Analog Converter.
> +	  Say yes here to build support for Analog Devices AD5024, AD5025, AD5044,
> +	  AD5045, AD5064, AD5064-1, AD5065 Digital to Analog Converter.
>
>   	  To compile this driver as a module, choose M here: the
>   	  module will be called ad5064.
> diff --git a/drivers/staging/iio/dac/ad5064.c b/drivers/staging/iio/dac/ad5064.c
> index 40db679..865e81f 100644
> --- a/drivers/staging/iio/dac/ad5064.c
> +++ b/drivers/staging/iio/dac/ad5064.c
> @@ -1,5 +1,6 @@
>   /*
> - * AD5064, AD5064-1, AD5044, AD5024 Digital to analog converters  driver
> + * AD5024, AD5025, AD5044, AD5045, AD5064, AD5064-1 Digital to analog converters
> + * driver
>    *
>    * Copyright 2011 Analog Devices Inc.
>    *
> @@ -84,9 +85,12 @@ struct ad5064_state {
>
>   enum ad5064_type {
>   	ID_AD5024,
> +	ID_AD5025,
>   	ID_AD5044,
> +	ID_AD5045,
>   	ID_AD5064,
>   	ID_AD5064_1,
> +	ID_AD5065,
>   };
>
>   static int ad5064_spi_write(struct ad5064_state *st, unsigned int cmd,
> @@ -301,11 +305,21 @@ static const struct ad5064_chip_info ad5064_chip_info_tbl[] = {
>   		.channels = ad5024_channels,
>   		.num_channels = 4,
>   	},
> +	[ID_AD5025] = {
> +		.shared_vref = false,
> +		.channels = ad5024_channels,
> +		.num_channels = 2,
> +	},
>   	[ID_AD5044] = {
>   		.shared_vref = false,
>   		.channels = ad5044_channels,
>   		.num_channels = 4,
>   	},
> +	[ID_AD5045] = {
> +		.shared_vref = false,
> +		.channels = ad5044_channels,
> +		.num_channels = 2,
> +	},
>   	[ID_AD5064] = {
>   		.shared_vref = false,
>   		.channels = ad5064_channels,
> @@ -316,6 +330,11 @@ static const struct ad5064_chip_info ad5064_chip_info_tbl[] = {
>   		.channels = ad5064_channels,
>   		.num_channels = 4,
>   	},
> +	[ID_AD5065] = {
> +		.shared_vref = false,
> +		.channels = ad5064_channels,
> +		.num_channels = 2,
> +	},
>   };
>
>   static inline unsigned int ad5064_num_vref(struct ad5064_state *st)
> @@ -412,9 +431,12 @@ static int __devexit ad5064_remove(struct spi_device *spi)
>
>   static const struct spi_device_id ad5064_id[] = {
>   	{"ad5024", ID_AD5024},
> +	{"ad5025", ID_AD5025},
>   	{"ad5044", ID_AD5044},
> +	{"ad5045", ID_AD5045},
>   	{"ad5064", ID_AD5064},
>   	{"ad5064-1", ID_AD5064_1},
> +	{"ad5065", ID_AD5065},
>   	{}
>   };
>   MODULE_DEVICE_TABLE(spi, ad5064_id);
> @@ -431,5 +453,5 @@ static struct spi_driver ad5064_driver = {
>   module_spi_driver(ad5064_driver);
>
>   MODULE_AUTHOR("Lars-Peter Clausen<lars@metafoo.de>");
> -MODULE_DESCRIPTION("Analog Devices AD5064/64-1/44/24 DAC");
> +MODULE_DESCRIPTION("Analog Devices AD5024/25/44/45/64/64-1/65 DAC");
>   MODULE_LICENSE("GPL v2");

Re: [PATCH v2 5/6] staging:iio:dac:ad5064: Add AD5628/AD5648/AD5668 support

[Jonathan Cameron]

On 2/20/2012 11:55 AM, Lars-Peter Clausen wrote:
> The AD5628/AD5648/AD5668 are similar to the AD5024/AD5044/AD5064. The difference
> being that they have an internal reference voltage and 8 instead of 4 DAC
> channels.
>
> Signed-off-by: Lars-Peter Clausen<lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
> ---
>   drivers/staging/iio/dac/Kconfig  |    5 +-
>   drivers/staging/iio/dac/ad5064.c |  122 ++++++++++++++++++++++++++++++++------
>   2 files changed, 107 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/staging/iio/dac/Kconfig b/drivers/staging/iio/dac/Kconfig
> index 66b2504..ab8516d 100644
> --- a/drivers/staging/iio/dac/Kconfig
> +++ b/drivers/staging/iio/dac/Kconfig
> @@ -4,11 +4,12 @@
>   menu "Digital to analog converters"
>
>   config AD5064
> -	tristate "Analog Devices AD5064/64-1/65/44/45/24/25 DAC driver"
> +	tristate "Analog Devices AD5064/64-1/65/44/45/24/25, AD5628/48/68 DAC driver"
>   	depends on SPI
>   	help
>   	  Say yes here to build support for Analog Devices AD5024, AD5025, AD5044,
> -	  AD5045, AD5064, AD5064-1, AD5065 Digital to Analog Converter.
> +	  AD5045, AD5064, AD5064-1, AD5065, AD5628, AD5648, AD5668 Digital to Analog
> +	  Converter.
>
>   	  To compile this driver as a module, choose M here: the
>   	  module will be called ad5064.
> diff --git a/drivers/staging/iio/dac/ad5064.c b/drivers/staging/iio/dac/ad5064.c
> index 865e81f..6dab064 100644
> --- a/drivers/staging/iio/dac/ad5064.c
> +++ b/drivers/staging/iio/dac/ad5064.c
> @@ -1,6 +1,6 @@
>   /*
> - * AD5024, AD5025, AD5044, AD5045, AD5064, AD5064-1 Digital to analog converters
> - * driver
> + * AD5024, AD5025, AD5044, AD5045, AD5064, AD5064-1, AD5065, AD5628, AD5648,
> + * AD5668 Digital to analog converters driver
>    *
>    * Copyright 2011 Analog Devices Inc.
>    *
> @@ -20,7 +20,7 @@
>   #include "../sysfs.h"
>   #include "dac.h"
>
> -#define AD5064_MAX_DAC_CHANNELS			4
> +#define AD5064_MAX_DAC_CHANNELS			8
>   #define AD5064_MAX_VREFS			4
>
>   #define AD5064_ADDR(x)				((x)<<  20)
> @@ -37,7 +37,10 @@
>   #define AD5064_CMD_CLEAR			0x5
>   #define AD5064_CMD_LDAC_MASK			0x6
>   #define AD5064_CMD_RESET			0x7
> -#define AD5064_CMD_DAISY_CHAIN_ENABLE		0x8
> +#define AD5064_CMD_CONFIG			0x8
> +
> +#define AD5064_CONFIG_DAISY_CHAIN_ENABLE	BIT(1)
> +#define AD5064_CONFIG_INT_VREF_ENABLE		BIT(0)
>
>   #define AD5064_LDAC_PWRDN_NONE			0x0
>   #define AD5064_LDAC_PWRDN_1K			0x1
> @@ -47,12 +50,15 @@
>   /**
>    * struct ad5064_chip_info - chip specific information
>    * @shared_vref:	whether the vref supply is shared between channels
> + * @internal_vref:	internal reference voltage. 0 if the chip has no internal
> + *			vref.
>    * @channel:		channel specification
>    * @num_channels:	number of channels
>    */
>
>   struct ad5064_chip_info {
>   	bool shared_vref;
> +	unsigned long internal_vref;
>   	const struct iio_chan_spec *channels;
>   	unsigned int num_channels;
>   };
> @@ -65,6 +71,8 @@ struct ad5064_chip_info {
>    * @pwr_down:		whether channel is powered down
>    * @pwr_down_mode:	channel's current power down mode
>    * @dac_cache:		current DAC raw value (chip does not support readback)
> + * @use_internal_vref:	set to true if the internal reference voltage should be
> + *			used.
>    * @data:		spi transfer buffers
>    */
>
> @@ -75,6 +83,7 @@ struct ad5064_state {
>   	bool				pwr_down[AD5064_MAX_DAC_CHANNELS];
>   	u8				pwr_down_mode[AD5064_MAX_DAC_CHANNELS];
>   	unsigned int			dac_cache[AD5064_MAX_DAC_CHANNELS];
> +	bool				use_internal_vref;
>
>   	/*
>   	 * DMA (thus cache coherency maintenance) requires the
> @@ -91,6 +100,12 @@ enum ad5064_type {
>   	ID_AD5064,
>   	ID_AD5064_1,
>   	ID_AD5065,
> +	ID_AD5628_1,
> +	ID_AD5628_2,
> +	ID_AD5648_1,
> +	ID_AD5648_2,
> +	ID_AD5668_1,
> +	ID_AD5668_2,
>   };
>
>   static int ad5064_spi_write(struct ad5064_state *st, unsigned int cmd,
> @@ -196,6 +211,18 @@ static ssize_t ad5064_write_dac_powerdown(struct iio_dev *indio_dev,
>   	return ret ? ret : len;
>   }
>
> +static int ad5064_get_vref(struct ad5064_state *st,
> +	struct iio_chan_spec const *chan)
> +{
> +	unsigned int i;
> +
> +	if (st->use_internal_vref)
> +		return st->chip_info->internal_vref;
> +
> +	i = st->chip_info->shared_vref ? 0 : chan->channel;
> +	return regulator_get_voltage(st->vref_reg[i].consumer);
> +}
> +
>   static int ad5064_read_raw(struct iio_dev *indio_dev,
>   			   struct iio_chan_spec const *chan,
>   			   int *val,
> @@ -203,7 +230,6 @@ static int ad5064_read_raw(struct iio_dev *indio_dev,
>   			   long m)
>   {
>   	struct ad5064_state *st = iio_priv(indio_dev);
> -	unsigned int vref;
>   	int scale_uv;
>
>   	switch (m) {
> @@ -211,8 +237,7 @@ static int ad5064_read_raw(struct iio_dev *indio_dev,
>   		*val = st->dac_cache[chan->channel];
>   		return IIO_VAL_INT;
>   	case IIO_CHAN_INFO_SCALE:
> -		vref = st->chip_info->shared_vref ? 0 : chan->channel;
> -		scale_uv = regulator_get_voltage(st->vref_reg[vref].consumer);
> +		scale_uv = ad5064_get_vref(st, chan);
>   		if (scale_uv<  0)
>   			return scale_uv;
>
> @@ -293,6 +318,10 @@ const struct iio_chan_spec name[] = { \
>   	AD5064_CHANNEL(1, bits), \
>   	AD5064_CHANNEL(2, bits), \
>   	AD5064_CHANNEL(3, bits), \
> +	AD5064_CHANNEL(4, bits), \
> +	AD5064_CHANNEL(5, bits), \
> +	AD5064_CHANNEL(6, bits), \
> +	AD5064_CHANNEL(7, bits), \
>   }
>
>   static DECLARE_AD5064_CHANNELS(ad5024_channels, 12);
> @@ -335,6 +364,42 @@ static const struct ad5064_chip_info ad5064_chip_info_tbl[] = {
>   		.channels = ad5064_channels,
>   		.num_channels = 2,
>   	},
> +	[ID_AD5628_1] = {
> +		.shared_vref = true,
> +		.internal_vref = 2500000,
> +		.channels = ad5024_channels,
> +		.num_channels = 8,
> +	},
> +	[ID_AD5628_2] = {
> +		.shared_vref = true,
> +		.internal_vref = 5000000,
> +		.channels = ad5024_channels,
> +		.num_channels = 8,
> +	},
> +	[ID_AD5648_1] = {
> +		.shared_vref = true,
> +		.internal_vref = 2500000,
> +		.channels = ad5044_channels,
> +		.num_channels = 8,
> +	},
> +	[ID_AD5648_2] = {
> +		.shared_vref = true,
> +		.internal_vref = 5000000,
> +		.channels = ad5044_channels,
> +		.num_channels = 8,
> +	},
> +	[ID_AD5668_1] = {
> +		.shared_vref = true,
> +		.internal_vref = 2500000,
> +		.channels = ad5064_channels,
> +		.num_channels = 8,
> +	},
> +	[ID_AD5668_2] = {
> +		.shared_vref = true,
> +		.internal_vref = 5000000,
> +		.channels = ad5064_channels,
> +		.num_channels = 8,
> +	},
>   };
>
>   static inline unsigned int ad5064_num_vref(struct ad5064_state *st)
> @@ -378,12 +443,22 @@ static int __devinit ad5064_probe(struct spi_device *spi)
>
>   	ret = regulator_bulk_get(&st->spi->dev, ad5064_num_vref(st),
>   		st->vref_reg);
> -	if (ret)
> -		goto error_free;
> -
> -	ret = regulator_bulk_enable(ad5064_num_vref(st), st->vref_reg);
> -	if (ret)
> -		goto error_free_reg;
> +	if (ret) {
> +		if (!st->chip_info->internal_vref)
> +			goto error_free;
> +		st->use_internal_vref = true;
> +		ret = ad5064_spi_write(st, AD5064_CMD_CONFIG, 0,
> +			AD5064_CONFIG_INT_VREF_ENABLE, 0);
> +		if (ret) {
> +			dev_err(&spi->dev, "Failed to enable internal vref: %d\n",
> +				ret);
> +			goto error_free;
> +		}
> +	} else {
> +		ret = regulator_bulk_enable(ad5064_num_vref(st), st->vref_reg);
> +		if (ret)
> +			goto error_free_reg;
> +	}
>
>   	for (i = 0; i<  st->chip_info->num_channels; ++i) {
>   		st->pwr_down_mode[i] = AD5064_LDAC_PWRDN_1K;
> @@ -404,9 +479,11 @@ static int __devinit ad5064_probe(struct spi_device *spi)
>   	return 0;
>
>   error_disable_reg:
> -	regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg);
> +	if (!st->use_internal_vref)
> +		regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg);
>   error_free_reg:
> -	regulator_bulk_free(ad5064_num_vref(st), st->vref_reg);
> +	if (!st->use_internal_vref)
> +		regulator_bulk_free(ad5064_num_vref(st), st->vref_reg);
>   error_free:
>   	iio_free_device(indio_dev);
>
> @@ -421,8 +498,10 @@ static int __devexit ad5064_remove(struct spi_device *spi)
>
>   	iio_device_unregister(indio_dev);
>
> -	regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg);
> -	regulator_bulk_free(ad5064_num_vref(st), st->vref_reg);
> +	if (!st->use_internal_vref) {
> +		regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg);
> +		regulator_bulk_free(ad5064_num_vref(st), st->vref_reg);
> +	}
>
>   	iio_free_device(indio_dev);
>
> @@ -437,6 +516,13 @@ static const struct spi_device_id ad5064_id[] = {
>   	{"ad5064", ID_AD5064},
>   	{"ad5064-1", ID_AD5064_1},
>   	{"ad5065", ID_AD5065},
> +	{"ad5628-1", ID_AD5628_1},
> +	{"ad5628-2", ID_AD5628_2},
> +	{"ad5648-1", ID_AD5648_1},
> +	{"ad5648-2", ID_AD5648_2},
> +	{"ad5668-1", ID_AD5668_1},
> +	{"ad5668-2", ID_AD5668_2},
> +	{"ad5668-3", ID_AD5668_2}, /* similar enough to ad5668-2 */
>   	{}
>   };
>   MODULE_DEVICE_TABLE(spi, ad5064_id);
> @@ -453,5 +539,5 @@ static struct spi_driver ad5064_driver = {
>   module_spi_driver(ad5064_driver);
>
>   MODULE_AUTHOR("Lars-Peter Clausen<lars@metafoo.de>");
> -MODULE_DESCRIPTION("Analog Devices AD5024/25/44/45/64/64-1/65 DAC");
> +MODULE_DESCRIPTION("Analog Devices AD5024/25/44/45/64/64-1/65, AD5628/48/68 DAC");
>   MODULE_LICENSE("GPL v2");

Re: [PATCH v2 1/6] staging:iio: Add extended IIO channel info

[Jonathan Cameron]

On 2/20/2012 11:55 AM, Lars-Peter Clausen wrote:
> Sometimes devices have per channel properties which either do not map nicely to
> the current channel info scheme (e.g. string properties) or are very device
> specific, so it does not make sense to add generic support for them.
>
> Currently drivers define these attributes by hand for each channel. Depending on
> the number of channels this can amount to quite a few lines of boilerplate code.
> Especially if a driver supports multiple variations of a chip with different
> numbers of channels. In this case it becomes necessary to have a individual
> attribute list per chip variation and also a individual iio_info struct.
>
> This patch introduces a new scheme for handling such per channel attributes
> called extended channel info attributes. A extended channel info attribute
> consist of a name, a flag whether it is shared and read and write callbacks.
> The read and write callbacks are similar to the {read,write}_raw callbacks and
> take a IIO device and a channel as their first parameters, but instead of
> pre-parsed integer values they directly get passed the raw string value, which
> has been written to the sysfs file.
>
> It is possible to assign a list of extended channel info attributes to a
> channel. For each extended channel info attribute the IIO core will create a new
> sysfs attribute conforming to the IIO channel naming spec for the channels type,
> similar as for normal info attributes. Read and write access to this sysfs
> attribute will be redirected to the extended channel info attributes read and
> write callbacks.
>
> Signed-off-by: Lars-Peter Clausen<lars@metafoo.de>
Other than one trivial nitpick.
Acked-by: Jonathan Cameron <jic23@kernel.org>

Note we'll have to be careful to make sure this facility doesn't get 
abused. But that should be
no harder than currently with the attrs.
>
> ---
> Changes since v1:
> 	* Do not move the -EBUSY handling for duplicated shared attributes to
> 	  __iio_add_chan_devattr since it will cause us to count shared attributes
> 	  multiple times, thus allocating more attributes than we actually use.
> ---
>   drivers/staging/iio/iio.h               |   23 +++++++++++++
>   drivers/staging/iio/industrialio-core.c |   54 +++++++++++++++++++++++++++++++
>   2 files changed, 77 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/staging/iio/iio.h b/drivers/staging/iio/iio.h
> index be6ced3..9140c2a 100644
> --- a/drivers/staging/iio/iio.h
> +++ b/drivers/staging/iio/iio.h
> @@ -88,6 +88,25 @@ enum iio_endian {
>   	IIO_LE,
>   };
>
> +struct iio_chan_spec;
> +struct iio_dev;
> +
> +/**
> + * struct iio_chan_spec_ext_info - Extended channel info attribute
> + * @name:	Info attribute name
> + * @shared:	Whether this attribute is shared between all channels.
> + * @read:	Read callback for this info attribute, may be NULL.
> + * @write:	Write callback for this info attribute, may be NULL.
> + */
> +struct iio_chan_spec_ext_info {
> +	const char *name;
> +	bool shared;
> +	ssize_t (*read)(struct iio_dev *, struct iio_chan_spec const *,
> +			char *buf);
> +	ssize_t (*write)(struct iio_dev *, struct iio_chan_spec const *,
> +			const char *buf, size_t len);
> +};
> +
>   /**
>    * struct iio_chan_spec - specification of a single channel
>    * @type:		What type of measurement is the channel making.
> @@ -107,6 +126,9 @@ enum iio_endian {
>    * @info_mask:		What information is to be exported about this channel.
>    *			This includes calibbias, scale etc.
>    * @event_mask:	What events can this channel produce.
> + * @ext_info:		Array of extended info attributes for this channel.
> + *			The array is NULL terminated, the last element should
> + *			have it's name field set to NULL.
>    * @extend_name:	Allows labeling of channel attributes with an
>    *			informative name. Note this has no effect codes etc,
>    *			unlike modifiers.
> @@ -141,6 +163,7 @@ struct iio_chan_spec {
>   	} scan_type;
>   	long			info_mask;
>   	long			event_mask;
> +	const struct iio_chan_spec_ext_info *ext_info;
>   	char			*extend_name;
>   	const char		*datasheet_name;
>   	unsigned		processed_val:1;
> diff --git a/drivers/staging/iio/industrialio-core.c b/drivers/staging/iio/industrialio-core.c
> index e4824fe..380b927 100644
> --- a/drivers/staging/iio/industrialio-core.c
> +++ b/drivers/staging/iio/industrialio-core.c
> @@ -144,6 +144,33 @@ static void __exit iio_exit(void)
>   	bus_unregister(&iio_bus_type);
>   }
>
> +static ssize_t iio_read_channel_ext_info(struct device *dev,
> +				     struct device_attribute *attr,
> +				     char *buf)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
> +	const struct iio_chan_spec_ext_info *ext_info;
> +
> +	ext_info =&this_attr->c->ext_info[this_attr->address];
> +
> +	return ext_info->read(indio_dev, this_attr->c, buf);
> +}
> +
> +static ssize_t iio_write_channel_ext_info(struct device *dev,
> +				     struct device_attribute *attr,
> +				     const char *buf,
> +					 size_t len)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
> +	const struct iio_chan_spec_ext_info *ext_info;
> +
> +	ext_info =&this_attr->c->ext_info[this_attr->address];
> +
> +	return ext_info->write(indio_dev, this_attr->c, buf, len);
> +}
> +
>   static ssize_t iio_read_channel_info(struct device *dev,
>   				     struct device_attribute *attr,
>   				     char *buf)
> @@ -423,6 +450,7 @@ static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
>   					struct iio_chan_spec const *chan)
>   {
>   	int ret, i, attrcount = 0;
> +	const struct iio_chan_spec_ext_info *ext_info;
>
>   	if (chan->channel<  0)
>   		return 0;
> @@ -457,6 +485,32 @@ static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
>   			goto error_ret;
>   		attrcount++;
>   	}
> +
> +	if (chan->ext_info) {
> +		unsigned int i = 0;
> +		for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
> +			ret = __iio_add_chan_devattr(ext_info->name,
> +					chan,
> +					ext_info->read ?
> +					&iio_read_channel_ext_info : NULL,
> +					ext_info->write ?
> +					&iio_write_channel_ext_info : NULL,
> +					i,
> +					ext_info->shared,
> +					&indio_dev->dev,
> +					&indio_dev->channel_attr_list);
> +			i++;
> +			if (ret == -EBUSY&&  ext_info->shared)
> +				continue;
> +
> +			if (ret)
> +				goto error_ret;
> +
> +			attrcount++;
> +		}
Excess blank line.
> +
> +	}
> +
>   	ret = attrcount;
>   error_ret:
>   	return ret;

Re: [PATCH v2 2/6] staging:iio:dac:ad5064: Convert to extended channel info attributes

[Jonathan Cameron]

On 2/20/2012 11:55 AM, Lars-Peter Clausen wrote:
> Use extended channel info attributes for the powerdown, powerdown_mode and
> powerdown_mode_available attributes.
>
> Note that this patch moves the chip info defintions around to avoid having to use
> forward declarations for the extended channel info attributes callbacks.
Nice series,
> Signed-off-by: Lars-Peter Clausen<lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
>
> ---
> Changes since v1:
> 	* Also make powerdown_mode_available an extended info attribute
> 	* Reorder code to avoid forward declarations
>
> Signed-off-by: Lars-Peter Clausen<lars@metafoo.de>
> ---
>   drivers/staging/iio/dac/ad5064.c |  188 +++++++++++++++++---------------------
>   1 files changed, 82 insertions(+), 106 deletions(-)
>
> diff --git a/drivers/staging/iio/dac/ad5064.c b/drivers/staging/iio/dac/ad5064.c
> index 049a855..52fef75 100644
> --- a/drivers/staging/iio/dac/ad5064.c
> +++ b/drivers/staging/iio/dac/ad5064.c
> @@ -86,47 +86,6 @@ enum ad5064_type {
>   	ID_AD5064_1,
>   };
>
> -#define AD5064_CHANNEL(chan, bits) {				\
> -	.type = IIO_VOLTAGE,					\
> -	.indexed = 1,						\
> -	.output = 1,						\
> -	.channel = (chan),					\
> -	.info_mask = IIO_CHAN_INFO_SCALE_SEPARATE_BIT,	\
> -	.address = AD5064_ADDR_DAC(chan),			\
> -	.scan_type = IIO_ST('u', (bits), 16, 20 - (bits))	\
> -}
> -
> -static const struct ad5064_chip_info ad5064_chip_info_tbl[] = {
> -	[ID_AD5024] = {
> -		.shared_vref = false,
> -		.channel[0] = AD5064_CHANNEL(0, 12),
> -		.channel[1] = AD5064_CHANNEL(1, 12),
> -		.channel[2] = AD5064_CHANNEL(2, 12),
> -		.channel[3] = AD5064_CHANNEL(3, 12),
> -	},
> -	[ID_AD5044] = {
> -		.shared_vref = false,
> -		.channel[0] = AD5064_CHANNEL(0, 14),
> -		.channel[1] = AD5064_CHANNEL(1, 14),
> -		.channel[2] = AD5064_CHANNEL(2, 14),
> -		.channel[3] = AD5064_CHANNEL(3, 14),
> -	},
> -	[ID_AD5064] = {
> -		.shared_vref = false,
> -		.channel[0] = AD5064_CHANNEL(0, 16),
> -		.channel[1] = AD5064_CHANNEL(1, 16),
> -		.channel[2] = AD5064_CHANNEL(2, 16),
> -		.channel[3] = AD5064_CHANNEL(3, 16),
> -	},
> -	[ID_AD5064_1] = {
> -		.shared_vref = true,
> -		.channel[0] = AD5064_CHANNEL(0, 16),
> -		.channel[1] = AD5064_CHANNEL(1, 16),
> -		.channel[2] = AD5064_CHANNEL(2, 16),
> -		.channel[3] = AD5064_CHANNEL(3, 16),
> -	},
> -};
> -
>   static int ad5064_spi_write(struct ad5064_state *st, unsigned int cmd,
>   	unsigned int addr, unsigned int val, unsigned int shift)
>   {
> @@ -160,22 +119,25 @@ static const char ad5064_powerdown_modes[][15] = {
>   	[AD5064_LDAC_PWRDN_3STATE]	= "three_state",
>   };
>
> -static ssize_t ad5064_read_powerdown_mode(struct device *dev,
> -	struct device_attribute *attr, char *buf)
> +static ssize_t ad5064_read_powerdown_mode_available(struct iio_dev *indio_dev,
> +	const struct iio_chan_spec *chan, char *buf)
> +{
> +	return sprintf(buf, "%s %s %s\n", ad5064_powerdown_modes[1],
> +		ad5064_powerdown_modes[2], ad5064_powerdown_modes[3]);
> +}
> +
> +static ssize_t ad5064_read_powerdown_mode(struct iio_dev *indio_dev,
> +	const struct iio_chan_spec *chan, char *buf)
>   {
> -	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
> -	struct iio_dev *indio_dev = dev_get_drvdata(dev);
>   	struct ad5064_state *st = iio_priv(indio_dev);
>
>   	return sprintf(buf, "%s\n",
> -		ad5064_powerdown_modes[st->pwr_down_mode[this_attr->address]]);
> +		ad5064_powerdown_modes[st->pwr_down_mode[chan->channel]]);
>   }
>
> -static ssize_t ad5064_write_powerdown_mode(struct device *dev,
> -	struct device_attribute *attr, const char *buf, size_t len)
> +static ssize_t ad5064_write_powerdown_mode(struct iio_dev *indio_dev,
> +	const struct iio_chan_spec *chan, const char *buf, size_t len)
>   {
> -	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
> -	struct iio_dev *indio_dev = dev_get_drvdata(dev);
>   	struct ad5064_state *st = iio_priv(indio_dev);
>   	unsigned int mode, i;
>   	int ret;
> @@ -192,31 +154,26 @@ static ssize_t ad5064_write_powerdown_mode(struct device *dev,
>   		return  -EINVAL;
>
>   	mutex_lock(&indio_dev->mlock);
> -	st->pwr_down_mode[this_attr->address] = mode;
> +	st->pwr_down_mode[chan->channel] = mode;
>
> -	ret = ad5064_sync_powerdown_mode(st, this_attr->address);
> +	ret = ad5064_sync_powerdown_mode(st, chan->channel);
>   	mutex_unlock(&indio_dev->mlock);
>
>   	return ret ? ret : len;
>   }
>
> -static ssize_t ad5064_read_dac_powerdown(struct device *dev,
> -					   struct device_attribute *attr,
> -					   char *buf)
> +static ssize_t ad5064_read_dac_powerdown(struct iio_dev *indio_dev,
> +	const struct iio_chan_spec *chan, char *buf)
>   {
> -	struct iio_dev *indio_dev = dev_get_drvdata(dev);
>   	struct ad5064_state *st = iio_priv(indio_dev);
> -	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
>
> -	return sprintf(buf, "%d\n", st->pwr_down[this_attr->address]);
> +	return sprintf(buf, "%d\n", st->pwr_down[chan->channel]);
>   }
>
> -static ssize_t ad5064_write_dac_powerdown(struct device *dev,
> -	struct device_attribute *attr, const char *buf, size_t len)
> +static ssize_t ad5064_write_dac_powerdown(struct iio_dev *indio_dev,
> +	const struct iio_chan_spec *chan, const char *buf, size_t len)
>   {
> -	struct iio_dev *indio_dev = dev_get_drvdata(dev);
>   	struct ad5064_state *st = iio_priv(indio_dev);
> -	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
>   	bool pwr_down;
>   	int ret;
>
> @@ -225,54 +182,13 @@ static ssize_t ad5064_write_dac_powerdown(struct device *dev,
>   		return ret;
>
>   	mutex_lock(&indio_dev->mlock);
> -	st->pwr_down[this_attr->address] = pwr_down;
> +	st->pwr_down[chan->channel] = pwr_down;
>
> -	ret = ad5064_sync_powerdown_mode(st, this_attr->address);
> +	ret = ad5064_sync_powerdown_mode(st, chan->channel);
>   	mutex_unlock(&indio_dev->mlock);
>   	return ret ? ret : len;
>   }
>
> -static IIO_CONST_ATTR(out_voltage_powerdown_mode_available,
> -			"1kohm_to_gnd 100kohm_to_gnd three_state");
> -
> -#define IIO_DEV_ATTR_DAC_POWERDOWN_MODE(_chan) \
> -	IIO_DEVICE_ATTR(out_voltage##_chan##_powerdown_mode, \
> -			S_IRUGO | S_IWUSR, \
> -			ad5064_read_powerdown_mode, \
> -			ad5064_write_powerdown_mode, _chan);
> -
> -#define IIO_DEV_ATTR_DAC_POWERDOWN(_chan)				\
> -	IIO_DEVICE_ATTR(out_voltage##_chan##_powerdown,			\
> -			S_IRUGO | S_IWUSR,				\
> -			ad5064_read_dac_powerdown,			\
> -			ad5064_write_dac_powerdown, _chan)
> -
> -static IIO_DEV_ATTR_DAC_POWERDOWN(0);
> -static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(0);
> -static IIO_DEV_ATTR_DAC_POWERDOWN(1);
> -static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(1);
> -static IIO_DEV_ATTR_DAC_POWERDOWN(2);
> -static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(2);
> -static IIO_DEV_ATTR_DAC_POWERDOWN(3);
> -static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(3);
> -
> -static struct attribute *ad5064_attributes[] = {
> -	&iio_dev_attr_out_voltage0_powerdown.dev_attr.attr,
> -	&iio_dev_attr_out_voltage1_powerdown.dev_attr.attr,
> -	&iio_dev_attr_out_voltage2_powerdown.dev_attr.attr,
> -	&iio_dev_attr_out_voltage3_powerdown.dev_attr.attr,
> -	&iio_dev_attr_out_voltage0_powerdown_mode.dev_attr.attr,
> -	&iio_dev_attr_out_voltage1_powerdown_mode.dev_attr.attr,
> -	&iio_dev_attr_out_voltage2_powerdown_mode.dev_attr.attr,
> -	&iio_dev_attr_out_voltage3_powerdown_mode.dev_attr.attr,
> -	&iio_const_attr_out_voltage_powerdown_mode_available.dev_attr.attr,
> -	NULL,
> -};
> -
> -static const struct attribute_group ad5064_attribute_group = {
> -	.attrs = ad5064_attributes,
> -};
> -
>   static int ad5064_read_raw(struct iio_dev *indio_dev,
>   			   struct iio_chan_spec const *chan,
>   			   int *val,
> @@ -331,10 +247,70 @@ static int ad5064_write_raw(struct iio_dev *indio_dev,
>   static const struct iio_info ad5064_info = {
>   	.read_raw = ad5064_read_raw,
>   	.write_raw = ad5064_write_raw,
> -	.attrs =&ad5064_attribute_group,
>   	.driver_module = THIS_MODULE,
>   };
>
> +static struct iio_chan_spec_ext_info ad5064_ext_info[] = {
> +	{
> +		.name = "powerdown",
> +		.read = ad5064_read_dac_powerdown,
> +		.write = ad5064_write_dac_powerdown,
> +	},
> +	{
> +		.name = "powerdown_mode",
> +		.read = ad5064_read_powerdown_mode,
> +		.write = ad5064_write_powerdown_mode,
> +	},
> +	{
> +		.name = "powerdown_mode_available",
> +		.shared = true,
> +		.read = ad5064_read_powerdown_mode_available,
> +	},
> +	{ },
> +};
> +
> +#define AD5064_CHANNEL(chan, bits) {				\
> +	.type = IIO_VOLTAGE,					\
> +	.indexed = 1,						\
> +	.output = 1,						\
> +	.channel = (chan),					\
> +	.info_mask = IIO_CHAN_INFO_SCALE_SEPARATE_BIT,	\
> +	.address = AD5064_ADDR_DAC(chan),			\
> +	.scan_type = IIO_ST('u', (bits), 16, 20 - (bits)),	\
> +	.ext_info = ad5064_ext_info,				\
> +}
> +
> +static const struct ad5064_chip_info ad5064_chip_info_tbl[] = {
> +	[ID_AD5024] = {
> +		.shared_vref = false,
> +		.channel[0] = AD5064_CHANNEL(0, 12),
> +		.channel[1] = AD5064_CHANNEL(1, 12),
> +		.channel[2] = AD5064_CHANNEL(2, 12),
> +		.channel[3] = AD5064_CHANNEL(3, 12),
> +	},
> +	[ID_AD5044] = {
> +		.shared_vref = false,
> +		.channel[0] = AD5064_CHANNEL(0, 14),
> +		.channel[1] = AD5064_CHANNEL(1, 14),
> +		.channel[2] = AD5064_CHANNEL(2, 14),
> +		.channel[3] = AD5064_CHANNEL(3, 14),
> +	},
> +	[ID_AD5064] = {
> +		.shared_vref = false,
> +		.channel[0] = AD5064_CHANNEL(0, 16),
> +		.channel[1] = AD5064_CHANNEL(1, 16),
> +		.channel[2] = AD5064_CHANNEL(2, 16),
> +		.channel[3] = AD5064_CHANNEL(3, 16),
> +	},
> +	[ID_AD5064_1] = {
> +		.shared_vref = true,
> +		.channel[0] = AD5064_CHANNEL(0, 16),
> +		.channel[1] = AD5064_CHANNEL(1, 16),
> +		.channel[2] = AD5064_CHANNEL(2, 16),
> +		.channel[3] = AD5064_CHANNEL(3, 16),
> +	},
> +};
> +
>   static inline unsigned int ad5064_num_vref(struct ad5064_state *st)
>   {
>   	return st->chip_info->shared_vref ? 1 : AD5064_DAC_CHANNELS;