iio: add info_mask_[shared_by_dir/shared_by_all]

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

drivers/iio/industrialio-core.c

@@ -551,6 +551,14 @@ 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",
@@ -578,6 +586,14 @@ 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",
@@ -736,6 +752,20 @@ 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++) {

include/linux/iio/iio.h

@@ -41,7 +41,9 @@ 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 {
@@ -156,6 +158,10 @@ 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
@@ -192,6 +198,8 @@ 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;
@@ -215,7 +223,9 @@ 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)						\