[PATCH V2 0/5] IIO: Refactor info_mask* and ext_info handling and introduce info_mask_shared_[by_all/by_type]

[PATCH V2 0/5] IIO: Refactor info_mask* and ext_info handling and introduce info_mask_shared_[by_all/by_type]

[Jonathan Cameron]

Changes since V1.
1) Deal with ext_info as well as the info_mask.
   In the previous set things sort of worked by coincidence of the ordering
   in the enum.  This version handles this cleanly.
2) Dropped the bonus const in tmp006.

Original message :

This series first performs a bit of refactoring of the core handling
of info_mask_separate and info_mask_shared_by_type.

Next we introduce info_mask_shared_by_dir and info_mask_shared_by_all
to allow for attributes of the form

in_sampling_frequency or sampling_frequency as appropriate.

Most existing drivers will make no use of the shared_by_dir
case, but it is there to handle devices with both and input and
output channels.

There are two main reasons for adding these two cases.
1) Should result in shorter code, particularly for complex drivers.
2) Allows for in kernel consumers accessing this functionality.

The intent is to follow this series with one providing a standard
way of providing 'available' attributes.  The combination of the
two should mean that very few things are still handled via direct
registration of attributes.

Thanks,

Jonathan



Jonathan Cameron (5):
  iio: drop info_mask from struct iio_dev
  iio: refactor info mask and ext_info attribute creation.
  iio: add info_mask_[shared_by_dir/shared_by_all]
  staging:iio: dummy driver additions to show shared_by_dir infomask
    usage
  iio:temperature:tmp006 put sampling_frequency in
    info_mask_shared_by_all

 drivers/iio/dac/ad5064.c               |   3 +-
 drivers/iio/dac/ad5380.c               |   4 +-
 drivers/iio/dac/ad5446.c               |   3 +-
 drivers/iio/dac/ad5504.c               |   4 +-
 drivers/iio/dac/ad5624r_spi.c          |   4 +-
 drivers/iio/dac/ad5686.c               |   3 +-
 drivers/iio/dac/ad5755.c               |   1 +
 drivers/iio/dac/ad5791.c               |   5 +-
 drivers/iio/dac/ad7303.c               |   1 +
 drivers/iio/dac/mcp4725.c              |   3 +-
 drivers/iio/frequency/adf4350.c        |   1 +
 drivers/iio/iio_core.h                 |   2 +-
 drivers/iio/industrialio-buffer.c      |   2 +-
 drivers/iio/industrialio-core.c        | 179 ++++++++++++++++++++-------------
 drivers/iio/temperature/tmp006.c       |  57 +++++------
 drivers/staging/iio/iio_simple_dummy.c |  16 +++
 include/linux/iio/iio.h                |  24 +++--
 17 files changed, 195 insertions(+), 117 deletions(-)

-- 
1.8.3.4

[PATCH 1/5] iio: drop info_mask from struct iio_dev

[Jonathan Cameron]

Somehow this got missed when dropping all the code that used it
prior to the split.  Remove it now, there are no users.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
---
 include/linux/iio/iio.h | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
index 2103cc3..cdb034d 100644
--- a/include/linux/iio/iio.h
+++ b/include/linux/iio/iio.h
@@ -146,12 +146,10 @@ ssize_t iio_enum_write(struct iio_dev *indio_dev,
  *			shift:		Shift right by this before masking out
  *					realbits.
  *			endianness:	little or big endian
- * @info_mask:		What information is to be exported about this channel.
- *			This includes calibbias, scale etc.
  * @info_mask_separate: What information is to be exported that is specific to
  *			this channel.
  * @info_mask_shared_by_type: What information is to be exported that is shared
-*			by all channels of the same type.
+ *			by all channels of the same type.
  * @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
@@ -186,7 +184,6 @@ struct iio_chan_spec {
 		u8	shift;
 		enum iio_endian endianness;
 	} scan_type;
-	long			info_mask;
 	long			info_mask_separate;
 	long			info_mask_shared_by_type;
 	long			event_mask;
-- 
1.8.3.4

[PATCH 2/5] iio: refactor info mask and ext_info attribute creation.

[Jonathan Cameron]

Introduce an enum to specify whether the attribute is separate or
shared.

Factor out the bitmap handling for loop into a separate function.

Tidy up error handling and add a NULL assignment to squish a false
positive warning from GCC.

Change ext_info shared type from boolean to enum and update in all
drivers.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
---
 drivers/iio/dac/ad5064.c          |   3 +-
 drivers/iio/dac/ad5380.c          |   4 +-
 drivers/iio/dac/ad5446.c          |   3 +-
 drivers/iio/dac/ad5504.c          |   4 +-
 drivers/iio/dac/ad5624r_spi.c     |   4 +-
 drivers/iio/dac/ad5686.c          |   3 +-
 drivers/iio/dac/ad5755.c          |   1 +
 drivers/iio/dac/ad5791.c          |   5 +-
 drivers/iio/dac/ad7303.c          |   1 +
 drivers/iio/dac/mcp4725.c         |   3 +-
 drivers/iio/frequency/adf4350.c   |   1 +
 drivers/iio/iio_core.h            |   2 +-
 drivers/iio/industrialio-buffer.c |   2 +-
 drivers/iio/industrialio-core.c   | 149 ++++++++++++++++++++------------------
 include/linux/iio/iio.h           |   7 +-
 15 files changed, 110 insertions(+), 82 deletions(-)

diff --git a/drivers/iio/dac/ad5064.c b/drivers/iio/dac/ad5064.c
index aa26d50..af66841 100644
--- a/drivers/iio/dac/ad5064.c
+++ b/drivers/iio/dac/ad5064.c
@@ -285,8 +285,9 @@ static const struct iio_chan_spec_ext_info ad5064_ext_info[] = {
 		.name = "powerdown",
 		.read = ad5064_read_dac_powerdown,
 		.write = ad5064_write_dac_powerdown,
+		.shared = IIO_SEPARATE,
 	},
-	IIO_ENUM("powerdown_mode", false, &ad5064_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SEPARATE, &ad5064_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5064_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/dac/ad5380.c b/drivers/iio/dac/ad5380.c
index bf2db02..3f1b9c3 100644
--- a/drivers/iio/dac/ad5380.c
+++ b/drivers/iio/dac/ad5380.c
@@ -247,8 +247,10 @@ static struct iio_chan_spec_ext_info ad5380_ext_info[] = {
 		.name = "powerdown",
 		.read = ad5380_read_dac_powerdown,
 		.write = ad5380_write_dac_powerdown,
+		.shared = IIO_SEPARATE,
 	},
-	IIO_ENUM("powerdown_mode", true, &ad5380_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
+		 &ad5380_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5380_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/dac/ad5446.c b/drivers/iio/dac/ad5446.c
index cae8f60..3fcc900 100644
--- a/drivers/iio/dac/ad5446.c
+++ b/drivers/iio/dac/ad5446.c
@@ -132,8 +132,9 @@ static const struct iio_chan_spec_ext_info ad5446_ext_info_powerdown[] = {
 		.name = "powerdown",
 		.read = ad5446_read_dac_powerdown,
 		.write = ad5446_write_dac_powerdown,
+		.shared = IIO_SEPARATE,
 	},
-	IIO_ENUM("powerdown_mode", false, &ad5446_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SEPARATE, &ad5446_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5446_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/dac/ad5504.c b/drivers/iio/dac/ad5504.c
index 139206e..06848d5 100644
--- a/drivers/iio/dac/ad5504.c
+++ b/drivers/iio/dac/ad5504.c
@@ -248,8 +248,10 @@ static const struct iio_chan_spec_ext_info ad5504_ext_info[] = {
 		.name = "powerdown",
 		.read = ad5504_read_dac_powerdown,
 		.write = ad5504_write_dac_powerdown,
+		.shared = IIO_SEPARATE,
 	},
-	IIO_ENUM("powerdown_mode", true, &ad5504_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
+		 &ad5504_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5504_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/dac/ad5624r_spi.c b/drivers/iio/dac/ad5624r_spi.c
index bb298aa..5f944ac 100644
--- a/drivers/iio/dac/ad5624r_spi.c
+++ b/drivers/iio/dac/ad5624r_spi.c
@@ -163,8 +163,10 @@ static const struct iio_chan_spec_ext_info ad5624r_ext_info[] = {
 		.name = "powerdown",
 		.read = ad5624r_read_dac_powerdown,
 		.write = ad5624r_write_dac_powerdown,
+		.shared = IIO_SEPARATE,
 	},
-	IIO_ENUM("powerdown_mode", true, &ad5624r_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
+		 &ad5624r_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5624r_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/dac/ad5686.c b/drivers/iio/dac/ad5686.c
index 06439b1..faf8ab5 100644
--- a/drivers/iio/dac/ad5686.c
+++ b/drivers/iio/dac/ad5686.c
@@ -265,8 +265,9 @@ static const struct iio_chan_spec_ext_info ad5686_ext_info[] = {
 		.name = "powerdown",
 		.read = ad5686_read_dac_powerdown,
 		.write = ad5686_write_dac_powerdown,
+		.shared = IIO_SEPARATE,
 	},
-	IIO_ENUM("powerdown_mode", false, &ad5686_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SEPARATE, &ad5686_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5686_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/dac/ad5755.c b/drivers/iio/dac/ad5755.c
index 12bb315..24f5d30 100644
--- a/drivers/iio/dac/ad5755.c
+++ b/drivers/iio/dac/ad5755.c
@@ -386,6 +386,7 @@ static const struct iio_chan_spec_ext_info ad5755_ext_info[] = {
 		.name = "powerdown",
 		.read = ad5755_read_powerdown,
 		.write = ad5755_write_powerdown,
+		.shared = IIO_SEPARATE,
 	},
 	{ },
 };
diff --git a/drivers/iio/dac/ad5791.c b/drivers/iio/dac/ad5791.c
index 97c1e5d..70866e1 100644
--- a/drivers/iio/dac/ad5791.c
+++ b/drivers/iio/dac/ad5791.c
@@ -287,11 +287,12 @@ static int ad5791_read_raw(struct iio_dev *indio_dev,
 static const struct iio_chan_spec_ext_info ad5791_ext_info[] = {
 	{
 		.name = "powerdown",
-		.shared = true,
+		.shared = IIO_SHARED_BY_TYPE,
 		.read = ad5791_read_dac_powerdown,
 		.write = ad5791_write_dac_powerdown,
 	},
-	IIO_ENUM("powerdown_mode", true, &ad5791_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
+		 &ad5791_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5791_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/dac/ad7303.c b/drivers/iio/dac/ad7303.c
index d546f50..3e0cb67 100644
--- a/drivers/iio/dac/ad7303.c
+++ b/drivers/iio/dac/ad7303.c
@@ -169,6 +169,7 @@ static const struct iio_chan_spec_ext_info ad7303_ext_info[] = {
 		.name = "powerdown",
 		.read = ad7303_read_dac_powerdown,
 		.write = ad7303_write_dac_powerdown,
+		.shared = IIO_SEPARATE,
 	},
 	{ },
 };
diff --git a/drivers/iio/dac/mcp4725.c b/drivers/iio/dac/mcp4725.c
index 1f4a48e..6711a33 100644
--- a/drivers/iio/dac/mcp4725.c
+++ b/drivers/iio/dac/mcp4725.c
@@ -195,8 +195,9 @@ static const struct iio_chan_spec_ext_info mcp4725_ext_info[] = {
 		.name = "powerdown",
 		.read = mcp4725_read_powerdown,
 		.write = mcp4725_write_powerdown,
+		.shared = IIO_SEPARATE,
 	},
-	IIO_ENUM("powerdown_mode", false, &mcp4725_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SEPARATE, &mcp4725_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &mcp4725_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/frequency/adf4350.c b/drivers/iio/frequency/adf4350.c
index a7b30be..85152547 100644
--- a/drivers/iio/frequency/adf4350.c
+++ b/drivers/iio/frequency/adf4350.c
@@ -351,6 +351,7 @@ static ssize_t adf4350_read(struct iio_dev *indio_dev,
 	.read = adf4350_read, \
 	.write = adf4350_write, \
 	.private = _ident, \
+	.shared = IIO_SEPARATE, \
 }
 
 static const struct iio_chan_spec_ext_info adf4350_ext_info[] = {
diff --git a/drivers/iio/iio_core.h b/drivers/iio/iio_core.h
index 05c1b74..6be5ab8 100644
--- a/drivers/iio/iio_core.h
+++ b/drivers/iio/iio_core.h
@@ -30,7 +30,7 @@ int __iio_add_chan_devattr(const char *postfix,
 						const char *buf,
 						size_t len),
 			   u64 mask,
-			   bool generic,
+			   enum iio_shared_by shared_by,
 			   struct device *dev,
 			   struct list_head *attr_list);
 
diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index e73033f..80a2e27 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -214,7 +214,7 @@ static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev,
 				     &iio_show_scan_index,
 				     NULL,
 				     0,
-				     0,
+				     IIO_SEPARATE,
 				     &indio_dev->dev,
 				     &buffer->scan_el_dev_attr_list);
 	if (ret)
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 97f0297..d713b20 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -516,14 +516,15 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
 						struct device_attribute *attr,
 						const char *buf,
 						size_t len),
-			   bool generic)
+			   enum iio_shared_by shared_by)
 {
-	int ret;
-	char *name_format, *full_postfix;
+	int ret = 0;
+	char *name_format = NULL;
+	char *full_postfix;
 	sysfs_attr_init(&dev_attr->attr);
 
 	/* Build up postfix of <extend_name>_<modifier>_postfix */
-	if (chan->modified && !generic) {
+	if (chan->modified && (shared_by == IIO_SEPARATE)) {
 		if (chan->extend_name)
 			full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
 						 iio_modifier_names[chan
@@ -544,53 +545,62 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
 						 chan->extend_name,
 						 postfix);
 	}
-	if (full_postfix == NULL) {
-		ret = -ENOMEM;
-		goto error_ret;
-	}
+	if (full_postfix == NULL)
+		return -ENOMEM;
 
 	if (chan->differential) { /* Differential can not have modifier */
-		if (generic)
+		switch (shared_by) {
+		case IIO_SHARED_BY_TYPE:
 			name_format
 				= kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
 					    iio_direction[chan->output],
 					    iio_chan_type_name_spec[chan->type],
 					    iio_chan_type_name_spec[chan->type],
 					    full_postfix);
-		else if (chan->indexed)
+			break;
+		case IIO_SEPARATE:
+			if (!chan->indexed) {
+				WARN_ON("Differential channels must be indexed\n");
+				ret = -EINVAL;
+				goto error_free_full_postfix;
+			}
 			name_format
-				= kasprintf(GFP_KERNEL, "%s_%s%d-%s%d_%s",
+				= kasprintf(GFP_KERNEL,
+					    "%s_%s%d-%s%d_%s",
 					    iio_direction[chan->output],
 					    iio_chan_type_name_spec[chan->type],
 					    chan->channel,
 					    iio_chan_type_name_spec[chan->type],
 					    chan->channel2,
 					    full_postfix);
-		else {
-			WARN_ON("Differential channels must be indexed\n");
-			ret = -EINVAL;
-			goto error_free_full_postfix;
+			break;
 		}
 	} else { /* Single ended */
-		if (generic)
-			name_format
-				= kasprintf(GFP_KERNEL, "%s_%s_%s",
-					    iio_direction[chan->output],
-					    iio_chan_type_name_spec[chan->type],
-					    full_postfix);
-		else if (chan->indexed)
-			name_format
-				= kasprintf(GFP_KERNEL, "%s_%s%d_%s",
-					    iio_direction[chan->output],
-					    iio_chan_type_name_spec[chan->type],
-					    chan->channel,
-					    full_postfix);
-		else
+		switch (shared_by) {
+		case IIO_SHARED_BY_TYPE:
 			name_format
 				= kasprintf(GFP_KERNEL, "%s_%s_%s",
 					    iio_direction[chan->output],
 					    iio_chan_type_name_spec[chan->type],
 					    full_postfix);
+			break;
+
+		case IIO_SEPARATE:
+			if (chan->indexed)
+				name_format
+					= kasprintf(GFP_KERNEL, "%s_%s%d_%s",
+						    iio_direction[chan->output],
+						    iio_chan_type_name_spec[chan->type],
+						    chan->channel,
+						    full_postfix);
+			else
+				name_format
+					= kasprintf(GFP_KERNEL, "%s_%s_%s",
+						    iio_direction[chan->output],
+						    iio_chan_type_name_spec[chan->type],
+						    full_postfix);
+			break;
+		}
 	}
 	if (name_format == NULL) {
 		ret = -ENOMEM;
@@ -614,16 +624,11 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
 		dev_attr->attr.mode |= S_IWUSR;
 		dev_attr->store = writefunc;
 	}
-	kfree(name_format);
-	kfree(full_postfix);
-
-	return 0;
-
 error_free_name_format:
 	kfree(name_format);
 error_free_full_postfix:
 	kfree(full_postfix);
-error_ret:
+
 	return ret;
 }
 
@@ -642,7 +647,7 @@ int __iio_add_chan_devattr(const char *postfix,
 						const char *buf,
 						size_t len),
 			   u64 mask,
-			   bool generic,
+			   enum iio_shared_by shared_by,
 			   struct device *dev,
 			   struct list_head *attr_list)
 {
@@ -656,7 +661,7 @@ int __iio_add_chan_devattr(const char *postfix,
 	}
 	ret = __iio_device_attr_init(&iio_attr->dev_attr,
 				     postfix, chan,
-				     readfunc, writefunc, generic);
+				     readfunc, writefunc, shared_by);
 	if (ret)
 		goto error_iio_dev_attr_free;
 	iio_attr->c = chan;
@@ -664,7 +669,7 @@ int __iio_add_chan_devattr(const char *postfix,
 	list_for_each_entry(t, attr_list, l)
 		if (strcmp(t->dev_attr.attr.name,
 			   iio_attr->dev_attr.attr.name) == 0) {
-			if (!generic)
+			if (shared_by == IIO_SEPARATE)
 				dev_err(dev, "tried to double register : %s\n",
 					t->dev_attr.attr.name);
 			ret = -EBUSY;
@@ -682,46 +687,54 @@ error_ret:
 	return ret;
 }
 
-static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
-					struct iio_chan_spec const *chan)
+static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
+					 struct iio_chan_spec const *chan,
+					 enum iio_shared_by shared_by,
+					 const long *infomask)
 {
-	int ret, attrcount = 0;
-	int i;
-	const struct iio_chan_spec_ext_info *ext_info;
+	int i, ret, attrcount = 0;
 
-	if (chan->channel < 0)
-		return 0;
-	for_each_set_bit(i, &chan->info_mask_separate, sizeof(long)*8) {
+	for_each_set_bit(i, infomask, sizeof(infomask)*8) {
 		ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
 					     chan,
 					     &iio_read_channel_info,
 					     &iio_write_channel_info,
 					     i,
-					     0,
+					     shared_by,
 					     &indio_dev->dev,
 					     &indio_dev->channel_attr_list);
-		if (ret < 0)
-			goto error_ret;
-		attrcount++;
-	}
-	for_each_set_bit(i, &chan->info_mask_shared_by_type, sizeof(long)*8) {
-		ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
-					     chan,
-					     &iio_read_channel_info,
-					     &iio_write_channel_info,
-					     i,
-					     1,
-					     &indio_dev->dev,
-					     &indio_dev->channel_attr_list);
-		if (ret == -EBUSY) {
-			ret = 0;
+		if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
 			continue;
-		} else if (ret < 0) {
-			goto error_ret;
-		}
+		else if (ret < 0)
+			return ret;
 		attrcount++;
 	}
 
+	return attrcount;
+}
+
+static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
+					struct iio_chan_spec const *chan)
+{
+	int ret, attrcount = 0;
+	const struct iio_chan_spec_ext_info *ext_info;
+
+	if (chan->channel < 0)
+		return 0;
+	ret = iio_device_add_info_mask_type(indio_dev, chan,
+					    IIO_SEPARATE,
+					    &chan->info_mask_separate);
+	if (ret < 0)
+		return ret;
+	attrcount += ret;
+
+	ret = iio_device_add_info_mask_type(indio_dev, chan,
+					    IIO_SHARED_BY_TYPE,
+					    &chan->info_mask_shared_by_type);
+	if (ret < 0)
+		return ret;
+	attrcount += ret;
+
 	if (chan->ext_info) {
 		unsigned int i = 0;
 		for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
@@ -740,15 +753,13 @@ static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
 				continue;
 
 			if (ret)
-				goto error_ret;
+				return ret;
 
 			attrcount++;
 		}
 	}
 
-	ret = attrcount;
-error_ret:
-	return ret;
+	return attrcount;
 }
 
 static void iio_device_remove_and_free_read_attr(struct iio_dev *indio_dev,
diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
index cdb034d..ad59fee 100644
--- a/include/linux/iio/iio.h
+++ b/include/linux/iio/iio.h
@@ -38,6 +38,9 @@ enum iio_chan_info_enum {
 	IIO_CHAN_INFO_HYSTERESIS,
 };
 
+enum iio_shared_by { IIO_SEPARATE,
+		     IIO_SHARED_BY_TYPE };
+
 enum iio_endian {
 	IIO_CPU,
 	IIO_BE,
@@ -57,7 +60,7 @@ struct iio_dev;
  */
 struct iio_chan_spec_ext_info {
 	const char *name;
-	bool shared;
+	enum iio_shared_by shared;
 	ssize_t (*read)(struct iio_dev *, uintptr_t private,
 			struct iio_chan_spec const *, char *buf);
 	ssize_t (*write)(struct iio_dev *, uintptr_t private,
@@ -125,7 +128,7 @@ ssize_t iio_enum_write(struct iio_dev *indio_dev,
 #define IIO_ENUM_AVAILABLE(_name, _e) \
 { \
 	.name = (_name "_available"), \
-	.shared = true, \
+	.shared = IIO_SHARED_BY_TYPE, \
 	.read = iio_enum_available_read, \
 	.private = (uintptr_t)(_e), \
 }
-- 
1.8.3.4

[PATCH 3/5] iio: add info_mask_[shared_by_dir/shared_by_all]

[Jonathan Cameron]

These two additional info_mask bitmaps should allow all 'standard'
numeric attributes to be handled using the read_raw and write_raw
callbacks.  Whilst this should reduce code, the more important element
is that this makes these values easily accessible to in kernel users
of IIO devices.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
---
 drivers/iio/industrialio-core.c | 30 ++++++++++++++++++++++++++++++
 include/linux/iio/iio.h         | 14 ++++++++++++--
 2 files changed, 42 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index d713b20..e3a5d12 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -550,6 +550,14 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
 
 	if (chan->differential) { /* Differential can not have modifier */
 		switch (shared_by) {
+		case IIO_SHARED_BY_ALL:
+			name_format = kasprintf(GFP_KERNEL, "%s", full_postfix);
+			break;
+		case IIO_SHARED_BY_DIR:
+			name_format = kasprintf(GFP_KERNEL, "%s_%s",
+						iio_direction[chan->output],
+						full_postfix);
+			break;
 		case IIO_SHARED_BY_TYPE:
 			name_format
 				= kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
@@ -577,6 +585,14 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
 		}
 	} else { /* Single ended */
 		switch (shared_by) {
+		case IIO_SHARED_BY_ALL:
+			name_format = kasprintf(GFP_KERNEL, "%s", full_postfix);
+			break;
+		case IIO_SHARED_BY_DIR:
+			name_format = kasprintf(GFP_KERNEL, "%s_%s",
+						iio_direction[chan->output],
+						full_postfix);
+			break;
 		case IIO_SHARED_BY_TYPE:
 			name_format
 				= kasprintf(GFP_KERNEL, "%s_%s_%s",
@@ -735,6 +751,20 @@ static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
 		return ret;
 	attrcount += ret;
 
+	ret = iio_device_add_info_mask_type(indio_dev, chan,
+					    IIO_SHARED_BY_DIR,
+					    &chan->info_mask_shared_by_dir);
+	if (ret < 0)
+		return ret;
+	attrcount += ret;
+
+	ret = iio_device_add_info_mask_type(indio_dev, chan,
+					    IIO_SHARED_BY_ALL,
+					    &chan->info_mask_shared_by_all);
+	if (ret < 0)
+		return ret;
+	attrcount += ret;
+
 	if (chan->ext_info) {
 		unsigned int i = 0;
 		for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
index ad59fee..e059fd4 100644
--- a/include/linux/iio/iio.h
+++ b/include/linux/iio/iio.h
@@ -39,7 +39,9 @@ enum iio_chan_info_enum {
 };
 
 enum iio_shared_by { IIO_SEPARATE,
-		     IIO_SHARED_BY_TYPE };
+		     IIO_SHARED_BY_TYPE,
+		     IIO_SHARED_BY_DIR,
+		     IIO_SHARED_BY_ALL };
 
 enum iio_endian {
 	IIO_CPU,
@@ -153,6 +155,10 @@ ssize_t iio_enum_write(struct iio_dev *indio_dev,
  *			this channel.
  * @info_mask_shared_by_type: What information is to be exported that is shared
  *			by all channels of the same type.
+ * @info_mask_shared_by_dir: What information is to be exported that is shared
+ *			by all channels of the same direction.
+ * @info_mask_shared_by_all: What information is to be exported that is shared
+ *			by all channels.
  * @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
@@ -189,6 +195,8 @@ struct iio_chan_spec {
 	} scan_type;
 	long			info_mask_separate;
 	long			info_mask_shared_by_type;
+	long			info_mask_shared_by_dir;
+	long			info_mask_shared_by_all;
 	long			event_mask;
 	const struct iio_chan_spec_ext_info *ext_info;
 	const char		*extend_name;
@@ -212,7 +220,9 @@ static inline bool iio_channel_has_info(const struct iio_chan_spec *chan,
 	enum iio_chan_info_enum type)
 {
 	return (chan->info_mask_separate & BIT(type)) |
-	       (chan->info_mask_shared_by_type & BIT(type));
+		(chan->info_mask_shared_by_type & BIT(type)) |
+		(chan->info_mask_shared_by_dir & BIT(type)) |
+		(chan->info_mask_shared_by_all & BIT(type));
 }
 
 #define IIO_ST(si, rb, sb, sh)						\
-- 
1.8.3.4

[PATCH 4/5] staging:iio: dummy driver additions to show shared_by_dir infomask usage

[Jonathan Cameron]

Note that as this driver has output as well as output channels an
example of info_mask_shared_by_all that makes any sense does not exist.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
---
 drivers/staging/iio/iio_simple_dummy.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/staging/iio/iio_simple_dummy.c b/drivers/staging/iio/iio_simple_dummy.c
index 0e8e02a..141ec61 100644
--- a/drivers/staging/iio/iio_simple_dummy.c
+++ b/drivers/staging/iio/iio_simple_dummy.c
@@ -90,6 +90,11 @@ static const struct iio_chan_spec iio_dummy_channels[] = {
 		 * when converting to standard units (microvolts)
 		 */
 		BIT(IIO_CHAN_INFO_SCALE),
+		/*
+		 * sampling_frequency
+		 * The frequency in Hz at which the channels are sampled
+		 */
+		.info_mask_shared_by_dir = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 		/* The ordering of elements in the buffer via an enum */
 		.scan_index = voltage0,
 		.scan_type = { /* Description of storage in buffer */
@@ -130,6 +135,10 @@ static const struct iio_chan_spec iio_dummy_channels[] = {
 		 * input channels of type IIO_VOLTAGE.
 		 */
 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
+		/*
+		 * sampling_frequency
+		 * The frequency in Hz at which the channels are sampled
+		 */
 		.scan_index = diffvoltage1m2,
 		.scan_type = { /* Description of storage in buffer */
 			.sign = 's', /* signed */
@@ -147,6 +156,7 @@ static const struct iio_chan_spec iio_dummy_channels[] = {
 		.channel2 = 4,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
+		.info_mask_shared_by_dir = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 		.scan_index = diffvoltage3m4,
 		.scan_type = {
 			.sign = 's',
@@ -173,6 +183,7 @@ static const struct iio_chan_spec iio_dummy_channels[] = {
 		 */
 		BIT(IIO_CHAN_INFO_CALIBSCALE) |
 		BIT(IIO_CHAN_INFO_CALIBBIAS),
+		.info_mask_shared_by_dir = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 		.scan_index = accelx,
 		.scan_type = { /* Description of storage in buffer */
 			.sign = 's', /* signed */
@@ -272,6 +283,11 @@ static int iio_dummy_read_raw(struct iio_dev *indio_dev,
 		*val2 = st->accel_calibscale->val2;
 		ret = IIO_VAL_INT_PLUS_MICRO;
 		break;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*val = 3;
+		*val2 = 33;
+		ret = IIO_VAL_INT_PLUS_NANO;
+		break;
 	default:
 		break;
 	}
-- 
1.8.3.4

[PATCH 5/5] iio:temperature:tmp006 put sampling_frequency in info_mask_shared_by_all

[Jonathan Cameron]

Doing this makes it possible to access this control from within the kernel.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Peter Meerwald <pmeerw@pmeerw.net>
---
 drivers/iio/temperature/tmp006.c | 57 +++++++++++++++++++---------------------
 1 file changed, 27 insertions(+), 30 deletions(-)

diff --git a/drivers/iio/temperature/tmp006.c b/drivers/iio/temperature/tmp006.c
index 64ccde3..4e95097 100644
--- a/drivers/iio/temperature/tmp006.c
+++ b/drivers/iio/temperature/tmp006.c
@@ -70,12 +70,16 @@ static int tmp006_read_measurement(struct tmp006_data *data, u8 reg)
 	return i2c_smbus_read_word_swapped(data->client, reg);
 }
 
+static const int tmp006_freqs[5][2] = { {4, 0}, {2, 0}, {1, 0},
+					{0, 500000}, {0, 250000} };
+
 static int tmp006_read_raw(struct iio_dev *indio_dev,
 			    struct iio_chan_spec const *channel, int *val,
 			    int *val2, long mask)
 {
 	struct tmp006_data *data = iio_priv(indio_dev);
 	s32 ret;
+	int cr;
 
 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
@@ -106,6 +110,12 @@ static int tmp006_read_raw(struct iio_dev *indio_dev,
 			break;
 		}
 		return IIO_VAL_INT_PLUS_MICRO;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		cr = (data->config & TMP006_CONFIG_CR_MASK)
+			>> TMP006_CONFIG_CR_SHIFT;
+		*val = tmp006_freqs[cr][0];
+		*val2 = tmp006_freqs[cr][1];
+		return IIO_VAL_INT_PLUS_MICRO;
 	default:
 		break;
 	}
@@ -113,48 +123,32 @@ static int tmp006_read_raw(struct iio_dev *indio_dev,
 	return -EINVAL;
 }
 
-static const char * const tmp006_freqs[] = { "4", "2", "1", "0.5", "0.25" };
-
-static ssize_t tmp006_show_freq(struct device *dev,
-				struct device_attribute *attr, char *buf)
-{
-	struct tmp006_data *data = iio_priv(dev_to_iio_dev(dev));
-	int cr = (data->config & TMP006_CONFIG_CR_MASK)
-		>> TMP006_CONFIG_CR_SHIFT;
-	return sprintf(buf, "%s\n", tmp006_freqs[cr]);
-}
-
-static ssize_t tmp006_store_freq(struct device *dev,
-				 struct device_attribute *attr,
-				 const char *buf, size_t len)
+static int tmp006_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int val,
+			    int val2,
+			    long mask)
 {
-	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct tmp006_data *data = iio_priv(indio_dev);
 	int i;
-	bool found = false;
 
 	for (i = 0; i < ARRAY_SIZE(tmp006_freqs); i++)
-		if (sysfs_streq(buf, tmp006_freqs[i])) {
-			found = true;
-			break;
-		}
-	if (!found)
-		return -EINVAL;
+		if ((val == tmp006_freqs[i][0]) &&
+		    (val2 == tmp006_freqs[i][1])) {
+			data->config &= ~TMP006_CONFIG_CR_MASK;
+			data->config |= i << TMP006_CONFIG_CR_SHIFT;
 
-	data->config &= ~TMP006_CONFIG_CR_MASK;
-	data->config |= i << TMP006_CONFIG_CR_SHIFT;
+			return i2c_smbus_write_word_swapped(data->client,
+							    TMP006_CONFIG,
+							    data->config);
 
-	return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG,
-		data->config);
+		}
+	return -EINVAL;
 }
 
-static IIO_DEV_ATTR_SAMP_FREQ(S_IRUGO | S_IWUSR,
-			tmp006_show_freq, tmp006_store_freq);
-
 static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25");
 
 static struct attribute *tmp006_attributes[] = {
-	&iio_dev_attr_sampling_frequency.dev_attr.attr,
 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
 	NULL
 };
@@ -168,16 +162,19 @@ static const struct iio_chan_spec tmp006_channels[] = {
 		.type = IIO_VOLTAGE,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 			BIT(IIO_CHAN_INFO_SCALE),
+		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 	},
 	{
 		.type = IIO_TEMP,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 			BIT(IIO_CHAN_INFO_SCALE),
+		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 	}
 };
 
 static const struct iio_info tmp006_info = {
 	.read_raw = tmp006_read_raw,
+	.write_raw = tmp006_write_raw,
 	.attrs = &tmp006_attribute_group,
 	.driver_module = THIS_MODULE,
 };
-- 
1.8.3.4

Re: [PATCH V2 0/5] IIO: Refactor info_mask* and ext_info handling and introduce info_mask_shared_[by_all/by_type]

[Jonathan Cameron]

If anyone has a chance to review this series, particularly patches 2 and 3 that
would be a great help!

Thanks,

Jonathan

On 08/18/13 16:50, Jonathan Cameron wrote:
> Changes since V1.
> 1) Deal with ext_info as well as the info_mask.
>    In the previous set things sort of worked by coincidence of the ordering
>    in the enum.  This version handles this cleanly.
> 2) Dropped the bonus const in tmp006.
> 
> Original message :
> 
> This series first performs a bit of refactoring of the core handling
> of info_mask_separate and info_mask_shared_by_type.
> 
> Next we introduce info_mask_shared_by_dir and info_mask_shared_by_all
> to allow for attributes of the form
> 
> in_sampling_frequency or sampling_frequency as appropriate.
> 
> Most existing drivers will make no use of the shared_by_dir
> case, but it is there to handle devices with both and input and
> output channels.
> 
> There are two main reasons for adding these two cases.
> 1) Should result in shorter code, particularly for complex drivers.
> 2) Allows for in kernel consumers accessing this functionality.
> 
> The intent is to follow this series with one providing a standard
> way of providing 'available' attributes.  The combination of the
> two should mean that very few things are still handled via direct
> registration of attributes.
> 
> Thanks,
> 
> Jonathan
> 
> 
> 
> Jonathan Cameron (5):
>   iio: drop info_mask from struct iio_dev
>   iio: refactor info mask and ext_info attribute creation.
>   iio: add info_mask_[shared_by_dir/shared_by_all]
>   staging:iio: dummy driver additions to show shared_by_dir infomask
>     usage
>   iio:temperature:tmp006 put sampling_frequency in
>     info_mask_shared_by_all
> 
>  drivers/iio/dac/ad5064.c               |   3 +-
>  drivers/iio/dac/ad5380.c               |   4 +-
>  drivers/iio/dac/ad5446.c               |   3 +-
>  drivers/iio/dac/ad5504.c               |   4 +-
>  drivers/iio/dac/ad5624r_spi.c          |   4 +-
>  drivers/iio/dac/ad5686.c               |   3 +-
>  drivers/iio/dac/ad5755.c               |   1 +
>  drivers/iio/dac/ad5791.c               |   5 +-
>  drivers/iio/dac/ad7303.c               |   1 +
>  drivers/iio/dac/mcp4725.c              |   3 +-
>  drivers/iio/frequency/adf4350.c        |   1 +
>  drivers/iio/iio_core.h                 |   2 +-
>  drivers/iio/industrialio-buffer.c      |   2 +-
>  drivers/iio/industrialio-core.c        | 179 ++++++++++++++++++++-------------
>  drivers/iio/temperature/tmp006.c       |  57 +++++------
>  drivers/staging/iio/iio_simple_dummy.c |  16 +++
>  include/linux/iio/iio.h                |  24 +++--
>  17 files changed, 195 insertions(+), 117 deletions(-)
> 

Re: [PATCH 2/5] iio: refactor info mask and ext_info attribute creation.

[Lars-Peter Clausen]

[...]
> diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
> index cdb034d..ad59fee 100644
> --- a/include/linux/iio/iio.h
> +++ b/include/linux/iio/iio.h
> @@ -38,6 +38,9 @@ enum iio_chan_info_enum {
>   	IIO_CHAN_INFO_HYSTERESIS,
>   };
>
> +enum iio_shared_by { IIO_SEPARATE,
> +		     IIO_SHARED_BY_TYPE };
> +

That's not kernel style formating, is it?

enum iio_shared_by {
	IIO_SEPARATE,
	IIO_SHARED_BY_TYPE,
};

... looks much better in my opinion

[...]

Re: [PATCH V2 0/5] IIO: Refactor info_mask* and ext_info handling and introduce info_mask_shared_[by_all/by_type]

[Lars-Peter Clausen]

On 08/18/2013 05:50 PM, Jonathan Cameron wrote:
> Changes since V1.
> 1) Deal with ext_info as well as the info_mask.
>     In the previous set things sort of worked by coincidence of the ordering
>     in the enum.  This version handles this cleanly.
> 2) Dropped the bonus const in tmp006.
>
> Original message :
>
> This series first performs a bit of refactoring of the core handling
> of info_mask_separate and info_mask_shared_by_type.
>
> Next we introduce info_mask_shared_by_dir and info_mask_shared_by_all
> to allow for attributes of the form
>
> in_sampling_frequency or sampling_frequency as appropriate.
>
> Most existing drivers will make no use of the shared_by_dir
> case, but it is there to handle devices with both and input and
> output channels.
>
> There are two main reasons for adding these two cases.
> 1) Should result in shorter code, particularly for complex drivers.
> 2) Allows for in kernel consumers accessing this functionality.
>
> The intent is to follow this series with one providing a standard
> way of providing 'available' attributes.  The combination of the
> two should mean that very few things are still handled via direct
> registration of attributes.

Makes sense and looks good, except for that enum formating issue.

Re: [PATCH 2/5] iio: refactor info mask and ext_info attribute creation.

[Jonathan Cameron]

On 09/05/13 20:24, Lars-Peter Clausen wrote:
> [...]
>> diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
>> index cdb034d..ad59fee 100644
>> --- a/include/linux/iio/iio.h
>> +++ b/include/linux/iio/iio.h
>> @@ -38,6 +38,9 @@ enum iio_chan_info_enum {
>>       IIO_CHAN_INFO_HYSTERESIS,
>>   };
>>
>> +enum iio_shared_by { IIO_SEPARATE,
>> +             IIO_SHARED_BY_TYPE };
>> +
> 
> That's not kernel style formating, is it?
> 
> enum iio_shared_by {
>     IIO_SEPARATE,
>     IIO_SHARED_BY_TYPE,
> };
> 
> ... looks much better in my opinion
> 
Fair point, v3 coming up.

> [...]
> 

[PATCH 2/5] iio: refactor info mask and ext_info attribute creation.

[Jonathan Cameron]

Introduce an enum to specify whether the attribute is separate or
shared.

Factor out the bitmap handling for loop into a separate function.

Tidy up error handling and add a NULL assignment to squish a false
positive warning from GCC.

Change ext_info shared type from boolean to enum and update in all
drivers.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
---
 drivers/iio/dac/ad5064.c          |   3 +-
 drivers/iio/dac/ad5380.c          |   4 +-
 drivers/iio/dac/ad5446.c          |   3 +-
 drivers/iio/dac/ad5504.c          |   4 +-
 drivers/iio/dac/ad5624r_spi.c     |   4 +-
 drivers/iio/dac/ad5686.c          |   3 +-
 drivers/iio/dac/ad5755.c          |   1 +
 drivers/iio/dac/ad5791.c          |   5 +-
 drivers/iio/dac/ad7303.c          |   1 +
 drivers/iio/dac/mcp4725.c         |   3 +-
 drivers/iio/frequency/adf4350.c   |   1 +
 drivers/iio/iio_core.h            |   2 +-
 drivers/iio/industrialio-buffer.c |   2 +-
 drivers/iio/industrialio-core.c   | 149 ++++++++++++++++++++------------------
 include/linux/iio/iio.h           |   9 ++-
 15 files changed, 112 insertions(+), 82 deletions(-)

diff --git a/drivers/iio/dac/ad5064.c b/drivers/iio/dac/ad5064.c
index aa26d50..af66841 100644
--- a/drivers/iio/dac/ad5064.c
+++ b/drivers/iio/dac/ad5064.c
@@ -285,8 +285,9 @@ static const struct iio_chan_spec_ext_info ad5064_ext_info[] = {
 		.name = "powerdown",
 		.read = ad5064_read_dac_powerdown,
 		.write = ad5064_write_dac_powerdown,
+		.shared = IIO_SEPARATE,
 	},
-	IIO_ENUM("powerdown_mode", false, &ad5064_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SEPARATE, &ad5064_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5064_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/dac/ad5380.c b/drivers/iio/dac/ad5380.c
index bf2db02..3f1b9c3 100644
--- a/drivers/iio/dac/ad5380.c
+++ b/drivers/iio/dac/ad5380.c
@@ -247,8 +247,10 @@ static struct iio_chan_spec_ext_info ad5380_ext_info[] = {
 		.name = "powerdown",
 		.read = ad5380_read_dac_powerdown,
 		.write = ad5380_write_dac_powerdown,
+		.shared = IIO_SEPARATE,
 	},
-	IIO_ENUM("powerdown_mode", true, &ad5380_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
+		 &ad5380_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5380_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/dac/ad5446.c b/drivers/iio/dac/ad5446.c
index cae8f60..3fcc900 100644
--- a/drivers/iio/dac/ad5446.c
+++ b/drivers/iio/dac/ad5446.c
@@ -132,8 +132,9 @@ static const struct iio_chan_spec_ext_info ad5446_ext_info_powerdown[] = {
 		.name = "powerdown",
 		.read = ad5446_read_dac_powerdown,
 		.write = ad5446_write_dac_powerdown,
+		.shared = IIO_SEPARATE,
 	},
-	IIO_ENUM("powerdown_mode", false, &ad5446_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SEPARATE, &ad5446_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5446_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/dac/ad5504.c b/drivers/iio/dac/ad5504.c
index 139206e..06848d5 100644
--- a/drivers/iio/dac/ad5504.c
+++ b/drivers/iio/dac/ad5504.c
@@ -248,8 +248,10 @@ static const struct iio_chan_spec_ext_info ad5504_ext_info[] = {
 		.name = "powerdown",
 		.read = ad5504_read_dac_powerdown,
 		.write = ad5504_write_dac_powerdown,
+		.shared = IIO_SEPARATE,
 	},
-	IIO_ENUM("powerdown_mode", true, &ad5504_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
+		 &ad5504_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5504_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/dac/ad5624r_spi.c b/drivers/iio/dac/ad5624r_spi.c
index bb298aa..5f944ac 100644
--- a/drivers/iio/dac/ad5624r_spi.c
+++ b/drivers/iio/dac/ad5624r_spi.c
@@ -163,8 +163,10 @@ static const struct iio_chan_spec_ext_info ad5624r_ext_info[] = {
 		.name = "powerdown",
 		.read = ad5624r_read_dac_powerdown,
 		.write = ad5624r_write_dac_powerdown,
+		.shared = IIO_SEPARATE,
 	},
-	IIO_ENUM("powerdown_mode", true, &ad5624r_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
+		 &ad5624r_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5624r_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/dac/ad5686.c b/drivers/iio/dac/ad5686.c
index 06439b1..faf8ab5 100644
--- a/drivers/iio/dac/ad5686.c
+++ b/drivers/iio/dac/ad5686.c
@@ -265,8 +265,9 @@ static const struct iio_chan_spec_ext_info ad5686_ext_info[] = {
 		.name = "powerdown",
 		.read = ad5686_read_dac_powerdown,
 		.write = ad5686_write_dac_powerdown,
+		.shared = IIO_SEPARATE,
 	},
-	IIO_ENUM("powerdown_mode", false, &ad5686_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SEPARATE, &ad5686_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5686_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/dac/ad5755.c b/drivers/iio/dac/ad5755.c
index 12bb315..24f5d30 100644
--- a/drivers/iio/dac/ad5755.c
+++ b/drivers/iio/dac/ad5755.c
@@ -386,6 +386,7 @@ static const struct iio_chan_spec_ext_info ad5755_ext_info[] = {
 		.name = "powerdown",
 		.read = ad5755_read_powerdown,
 		.write = ad5755_write_powerdown,
+		.shared = IIO_SEPARATE,
 	},
 	{ },
 };
diff --git a/drivers/iio/dac/ad5791.c b/drivers/iio/dac/ad5791.c
index 97c1e5d..70866e1 100644
--- a/drivers/iio/dac/ad5791.c
+++ b/drivers/iio/dac/ad5791.c
@@ -287,11 +287,12 @@ static int ad5791_read_raw(struct iio_dev *indio_dev,
 static const struct iio_chan_spec_ext_info ad5791_ext_info[] = {
 	{
 		.name = "powerdown",
-		.shared = true,
+		.shared = IIO_SHARED_BY_TYPE,
 		.read = ad5791_read_dac_powerdown,
 		.write = ad5791_write_dac_powerdown,
 	},
-	IIO_ENUM("powerdown_mode", true, &ad5791_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
+		 &ad5791_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5791_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/dac/ad7303.c b/drivers/iio/dac/ad7303.c
index d546f50..3e0cb67 100644
--- a/drivers/iio/dac/ad7303.c
+++ b/drivers/iio/dac/ad7303.c
@@ -169,6 +169,7 @@ static const struct iio_chan_spec_ext_info ad7303_ext_info[] = {
 		.name = "powerdown",
 		.read = ad7303_read_dac_powerdown,
 		.write = ad7303_write_dac_powerdown,
+		.shared = IIO_SEPARATE,
 	},
 	{ },
 };
diff --git a/drivers/iio/dac/mcp4725.c b/drivers/iio/dac/mcp4725.c
index 1f4a48e..6711a33 100644
--- a/drivers/iio/dac/mcp4725.c
+++ b/drivers/iio/dac/mcp4725.c
@@ -195,8 +195,9 @@ static const struct iio_chan_spec_ext_info mcp4725_ext_info[] = {
 		.name = "powerdown",
 		.read = mcp4725_read_powerdown,
 		.write = mcp4725_write_powerdown,
+		.shared = IIO_SEPARATE,
 	},
-	IIO_ENUM("powerdown_mode", false, &mcp4725_powerdown_mode_enum),
+	IIO_ENUM("powerdown_mode", IIO_SEPARATE, &mcp4725_powerdown_mode_enum),
 	IIO_ENUM_AVAILABLE("powerdown_mode", &mcp4725_powerdown_mode_enum),
 	{ },
 };
diff --git a/drivers/iio/frequency/adf4350.c b/drivers/iio/frequency/adf4350.c
index a7b30be..85152547 100644
--- a/drivers/iio/frequency/adf4350.c
+++ b/drivers/iio/frequency/adf4350.c
@@ -351,6 +351,7 @@ static ssize_t adf4350_read(struct iio_dev *indio_dev,
 	.read = adf4350_read, \
 	.write = adf4350_write, \
 	.private = _ident, \
+	.shared = IIO_SEPARATE, \
 }
 
 static const struct iio_chan_spec_ext_info adf4350_ext_info[] = {
diff --git a/drivers/iio/iio_core.h b/drivers/iio/iio_core.h
index 05c1b74..6be5ab8 100644
--- a/drivers/iio/iio_core.h
+++ b/drivers/iio/iio_core.h
@@ -30,7 +30,7 @@ int __iio_add_chan_devattr(const char *postfix,
 						const char *buf,
 						size_t len),
 			   u64 mask,
-			   bool generic,
+			   enum iio_shared_by shared_by,
 			   struct device *dev,
 			   struct list_head *attr_list);
 
diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index e73033f..80a2e27 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -214,7 +214,7 @@ static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev,
 				     &iio_show_scan_index,
 				     NULL,
 				     0,
-				     0,
+				     IIO_SEPARATE,
 				     &indio_dev->dev,
 				     &buffer->scan_el_dev_attr_list);
 	if (ret)
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 97f0297..d713b20 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -516,14 +516,15 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
 						struct device_attribute *attr,
 						const char *buf,
 						size_t len),
-			   bool generic)
+			   enum iio_shared_by shared_by)
 {
-	int ret;
-	char *name_format, *full_postfix;
+	int ret = 0;
+	char *name_format = NULL;
+	char *full_postfix;
 	sysfs_attr_init(&dev_attr->attr);
 
 	/* Build up postfix of <extend_name>_<modifier>_postfix */
-	if (chan->modified && !generic) {
+	if (chan->modified && (shared_by == IIO_SEPARATE)) {
 		if (chan->extend_name)
 			full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
 						 iio_modifier_names[chan
@@ -544,53 +545,62 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
 						 chan->extend_name,
 						 postfix);
 	}
-	if (full_postfix == NULL) {
-		ret = -ENOMEM;
-		goto error_ret;
-	}
+	if (full_postfix == NULL)
+		return -ENOMEM;
 
 	if (chan->differential) { /* Differential can not have modifier */
-		if (generic)
+		switch (shared_by) {
+		case IIO_SHARED_BY_TYPE:
 			name_format
 				= kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
 					    iio_direction[chan->output],
 					    iio_chan_type_name_spec[chan->type],
 					    iio_chan_type_name_spec[chan->type],
 					    full_postfix);
-		else if (chan->indexed)
+			break;
+		case IIO_SEPARATE:
+			if (!chan->indexed) {
+				WARN_ON("Differential channels must be indexed\n");
+				ret = -EINVAL;
+				goto error_free_full_postfix;
+			}
 			name_format
-				= kasprintf(GFP_KERNEL, "%s_%s%d-%s%d_%s",
+				= kasprintf(GFP_KERNEL,
+					    "%s_%s%d-%s%d_%s",
 					    iio_direction[chan->output],
 					    iio_chan_type_name_spec[chan->type],
 					    chan->channel,
 					    iio_chan_type_name_spec[chan->type],
 					    chan->channel2,
 					    full_postfix);
-		else {
-			WARN_ON("Differential channels must be indexed\n");
-			ret = -EINVAL;
-			goto error_free_full_postfix;
+			break;
 		}
 	} else { /* Single ended */
-		if (generic)
-			name_format
-				= kasprintf(GFP_KERNEL, "%s_%s_%s",
-					    iio_direction[chan->output],
-					    iio_chan_type_name_spec[chan->type],
-					    full_postfix);
-		else if (chan->indexed)
-			name_format
-				= kasprintf(GFP_KERNEL, "%s_%s%d_%s",
-					    iio_direction[chan->output],
-					    iio_chan_type_name_spec[chan->type],
-					    chan->channel,
-					    full_postfix);
-		else
+		switch (shared_by) {
+		case IIO_SHARED_BY_TYPE:
 			name_format
 				= kasprintf(GFP_KERNEL, "%s_%s_%s",
 					    iio_direction[chan->output],
 					    iio_chan_type_name_spec[chan->type],
 					    full_postfix);
+			break;
+
+		case IIO_SEPARATE:
+			if (chan->indexed)
+				name_format
+					= kasprintf(GFP_KERNEL, "%s_%s%d_%s",
+						    iio_direction[chan->output],
+						    iio_chan_type_name_spec[chan->type],
+						    chan->channel,
+						    full_postfix);
+			else
+				name_format
+					= kasprintf(GFP_KERNEL, "%s_%s_%s",
+						    iio_direction[chan->output],
+						    iio_chan_type_name_spec[chan->type],
+						    full_postfix);
+			break;
+		}
 	}
 	if (name_format == NULL) {
 		ret = -ENOMEM;
@@ -614,16 +624,11 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
 		dev_attr->attr.mode |= S_IWUSR;
 		dev_attr->store = writefunc;
 	}
-	kfree(name_format);
-	kfree(full_postfix);
-
-	return 0;
-
 error_free_name_format:
 	kfree(name_format);
 error_free_full_postfix:
 	kfree(full_postfix);
-error_ret:
+
 	return ret;
 }
 
@@ -642,7 +647,7 @@ int __iio_add_chan_devattr(const char *postfix,
 						const char *buf,
 						size_t len),
 			   u64 mask,
-			   bool generic,
+			   enum iio_shared_by shared_by,
 			   struct device *dev,
 			   struct list_head *attr_list)
 {
@@ -656,7 +661,7 @@ int __iio_add_chan_devattr(const char *postfix,
 	}
 	ret = __iio_device_attr_init(&iio_attr->dev_attr,
 				     postfix, chan,
-				     readfunc, writefunc, generic);
+				     readfunc, writefunc, shared_by);
 	if (ret)
 		goto error_iio_dev_attr_free;
 	iio_attr->c = chan;
@@ -664,7 +669,7 @@ int __iio_add_chan_devattr(const char *postfix,
 	list_for_each_entry(t, attr_list, l)
 		if (strcmp(t->dev_attr.attr.name,
 			   iio_attr->dev_attr.attr.name) == 0) {
-			if (!generic)
+			if (shared_by == IIO_SEPARATE)
 				dev_err(dev, "tried to double register : %s\n",
 					t->dev_attr.attr.name);
 			ret = -EBUSY;
@@ -682,46 +687,54 @@ error_ret:
 	return ret;
 }
 
-static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
-					struct iio_chan_spec const *chan)
+static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
+					 struct iio_chan_spec const *chan,
+					 enum iio_shared_by shared_by,
+					 const long *infomask)
 {
-	int ret, attrcount = 0;
-	int i;
-	const struct iio_chan_spec_ext_info *ext_info;
+	int i, ret, attrcount = 0;
 
-	if (chan->channel < 0)
-		return 0;
-	for_each_set_bit(i, &chan->info_mask_separate, sizeof(long)*8) {
+	for_each_set_bit(i, infomask, sizeof(infomask)*8) {
 		ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
 					     chan,
 					     &iio_read_channel_info,
 					     &iio_write_channel_info,
 					     i,
-					     0,
+					     shared_by,
 					     &indio_dev->dev,
 					     &indio_dev->channel_attr_list);
-		if (ret < 0)
-			goto error_ret;
-		attrcount++;
-	}
-	for_each_set_bit(i, &chan->info_mask_shared_by_type, sizeof(long)*8) {
-		ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
-					     chan,
-					     &iio_read_channel_info,
-					     &iio_write_channel_info,
-					     i,
-					     1,
-					     &indio_dev->dev,
-					     &indio_dev->channel_attr_list);
-		if (ret == -EBUSY) {
-			ret = 0;
+		if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
 			continue;
-		} else if (ret < 0) {
-			goto error_ret;
-		}
+		else if (ret < 0)
+			return ret;
 		attrcount++;
 	}
 
+	return attrcount;
+}
+
+static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
+					struct iio_chan_spec const *chan)
+{
+	int ret, attrcount = 0;
+	const struct iio_chan_spec_ext_info *ext_info;
+
+	if (chan->channel < 0)
+		return 0;
+	ret = iio_device_add_info_mask_type(indio_dev, chan,
+					    IIO_SEPARATE,
+					    &chan->info_mask_separate);
+	if (ret < 0)
+		return ret;
+	attrcount += ret;
+
+	ret = iio_device_add_info_mask_type(indio_dev, chan,
+					    IIO_SHARED_BY_TYPE,
+					    &chan->info_mask_shared_by_type);
+	if (ret < 0)
+		return ret;
+	attrcount += ret;
+
 	if (chan->ext_info) {
 		unsigned int i = 0;
 		for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
@@ -740,15 +753,13 @@ static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
 				continue;
 
 			if (ret)
-				goto error_ret;
+				return ret;
 
 			attrcount++;
 		}
 	}
 
-	ret = attrcount;
-error_ret:
-	return ret;
+	return attrcount;
 }
 
 static void iio_device_remove_and_free_read_attr(struct iio_dev *indio_dev,
diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
index cdb034d..8d769fe 100644
--- a/include/linux/iio/iio.h
+++ b/include/linux/iio/iio.h
@@ -38,6 +38,11 @@ enum iio_chan_info_enum {
 	IIO_CHAN_INFO_HYSTERESIS,
 };
 
+enum iio_shared_by {
+	IIO_SEPARATE,
+	IIO_SHARED_BY_TYPE
+};
+
 enum iio_endian {
 	IIO_CPU,
 	IIO_BE,
@@ -57,7 +62,7 @@ struct iio_dev;
  */
 struct iio_chan_spec_ext_info {
 	const char *name;
-	bool shared;
+	enum iio_shared_by shared;
 	ssize_t (*read)(struct iio_dev *, uintptr_t private,
 			struct iio_chan_spec const *, char *buf);
 	ssize_t (*write)(struct iio_dev *, uintptr_t private,
@@ -125,7 +130,7 @@ ssize_t iio_enum_write(struct iio_dev *indio_dev,
 #define IIO_ENUM_AVAILABLE(_name, _e) \
 { \
 	.name = (_name "_available"), \
-	.shared = true, \
+	.shared = IIO_SHARED_BY_TYPE, \
 	.read = iio_enum_available_read, \
 	.private = (uintptr_t)(_e), \
 }
-- 
1.8.4