[PATCH v4 07/17] iio: add reference to iio buffer on iio_dev_attr

From: Alexandru Ardelean
Date: Wed Feb 10 2021 - 05:10:37 EST


This change adds a reference to a 'struct iio_buffer' object on the
iio_dev_attr object. This way, we can use the created iio_dev_attr objects
on per-buffer basis (since they're allocated anyway).

A minor downside of this change is that the number of parameters on
__iio_add_chan_devattr() grows by 1. This looks like it could do with a bit
of a re-think.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
---
drivers/iio/iio_core.h | 2 ++
drivers/iio/industrialio-buffer.c | 4 ++++
drivers/iio/industrialio-core.c | 6 ++++++
drivers/iio/industrialio-event.c | 1 +
include/linux/iio/sysfs.h | 3 +++
5 files changed, 16 insertions(+)

diff --git a/drivers/iio/iio_core.h b/drivers/iio/iio_core.h
index 7d5b179c1fe7..731f5170d5b9 100644
--- a/drivers/iio/iio_core.h
+++ b/drivers/iio/iio_core.h
@@ -12,6 +12,7 @@
#include <linux/kernel.h>
#include <linux/device.h>

+struct iio_buffer;
struct iio_chan_spec;
struct iio_dev;

@@ -43,6 +44,7 @@ int __iio_add_chan_devattr(const char *postfix,
u64 mask,
enum iio_shared_by shared_by,
struct device *dev,
+ struct iio_buffer *buffer,
struct list_head *attr_list);
void iio_free_chan_devattr_list(struct list_head *attr_list);

diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index fcbbffb904bf..530b8697f3d8 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -447,6 +447,7 @@ static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev,
0,
IIO_SEPARATE,
&indio_dev->dev,
+ buffer,
&buffer->scan_el_dev_attr_list);
if (ret)
return ret;
@@ -458,6 +459,7 @@ static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev,
0,
0,
&indio_dev->dev,
+ buffer,
&buffer->scan_el_dev_attr_list);
if (ret)
return ret;
@@ -470,6 +472,7 @@ static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev,
chan->scan_index,
0,
&indio_dev->dev,
+ buffer,
&buffer->scan_el_dev_attr_list);
else
ret = __iio_add_chan_devattr("en",
@@ -479,6 +482,7 @@ static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev,
chan->scan_index,
0,
&indio_dev->dev,
+ buffer,
&buffer->scan_el_dev_attr_list);
if (ret)
return ret;
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 2db460ac30b2..2e8e656e41dd 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -1114,6 +1114,7 @@ int __iio_add_chan_devattr(const char *postfix,
u64 mask,
enum iio_shared_by shared_by,
struct device *dev,
+ struct iio_buffer *buffer,
struct list_head *attr_list)
{
int ret;
@@ -1129,6 +1130,7 @@ int __iio_add_chan_devattr(const char *postfix,
goto error_iio_dev_attr_free;
iio_attr->c = chan;
iio_attr->address = mask;
+ iio_attr->buffer = buffer;
list_for_each_entry(t, attr_list, l)
if (strcmp(t->dev_attr.attr.name,
iio_attr->dev_attr.attr.name) == 0) {
@@ -1165,6 +1167,7 @@ static int iio_device_add_channel_label(struct iio_dev *indio_dev,
0,
IIO_SEPARATE,
&indio_dev->dev,
+ NULL,
&iio_dev_opaque->channel_attr_list);
if (ret < 0)
return ret;
@@ -1190,6 +1193,7 @@ static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
i,
shared_by,
&indio_dev->dev,
+ NULL,
&iio_dev_opaque->channel_attr_list);
if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
continue;
@@ -1226,6 +1230,7 @@ static int iio_device_add_info_mask_type_avail(struct iio_dev *indio_dev,
i,
shared_by,
&indio_dev->dev,
+ NULL,
&iio_dev_opaque->channel_attr_list);
kfree(avail_postfix);
if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
@@ -1322,6 +1327,7 @@ static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
i,
ext_info->shared,
&indio_dev->dev,
+ NULL,
&iio_dev_opaque->channel_attr_list);
i++;
if (ret == -EBUSY && ext_info->shared)
diff --git a/drivers/iio/industrialio-event.c b/drivers/iio/industrialio-event.c
index ea8947cc21e4..a30e289fc362 100644
--- a/drivers/iio/industrialio-event.c
+++ b/drivers/iio/industrialio-event.c
@@ -385,6 +385,7 @@ static int iio_device_add_event(struct iio_dev *indio_dev,

ret = __iio_add_chan_devattr(postfix, chan, show, store,
(i << 16) | spec_index, shared_by, &indio_dev->dev,
+ NULL,
&iio_dev_opaque->event_interface->dev_attr_list);
kfree(postfix);

diff --git a/include/linux/iio/sysfs.h b/include/linux/iio/sysfs.h
index b532c875bc24..e51fba66de4b 100644
--- a/include/linux/iio/sysfs.h
+++ b/include/linux/iio/sysfs.h
@@ -9,6 +9,7 @@
#ifndef _INDUSTRIAL_IO_SYSFS_H_
#define _INDUSTRIAL_IO_SYSFS_H_

+struct iio_buffer;
struct iio_chan_spec;

/**
@@ -17,12 +18,14 @@ struct iio_chan_spec;
* @address: associated register address
* @l: list head for maintaining list of dynamically created attrs
* @c: specification for the underlying channel
+ * @buffer: the IIO buffer to which this attribute belongs to (if any)
*/
struct iio_dev_attr {
struct device_attribute dev_attr;
u64 address;
struct list_head l;
struct iio_chan_spec const *c;
+ struct iio_buffer *buffer;
};

#define to_iio_dev_attr(_dev_attr) \
--
2.17.1