iio: triggered-buffer: add {devm_}iio_triggered_buffer_setup_ext variants

This change adds a parameter to the {devm_}iio_triggered_buffer_setup()
functions to assign the extra sysfs buffer attributes that are typically
assigned via iio_buffer_set_attrs().

The functions also get renamed to iio_triggered_buffer_setup_ext() &
devm_iio_triggered_buffer_setup_ext().
For backwards compatibility the old {devm_}iio_triggered_buffer_setup()
functions are now macros wrap the new (renamed) functions with NULL for the
buffer attrs.

The aim is to remove iio_buffer_set_attrs(), so in the
iio_triggered_buffer_setup_ext() function the attributes are assigned
directly to 'buffer->attrs'.

When adding multiple IIO buffers per IIO device, it can be pretty
cumbersome to first allocate a set of buffers, then to dig them out of IIO
to assign extra attributes (with iio_buffer_set_attrs()).

Naturally, the best way would be to provide them at allocation time, which
is what this change does.

At this moment, buffers allocated with {devm_}iio_triggered_buffer_setup()
are the only ones in mainline IIO to call iio_buffer_set_attrs().

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20200929125949.69934-4-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/buffer/industrialio-triggered-buffer.c b/drivers/iio/buffer/industrialio-triggered-buffer.c
index 6c20a83f887e53c5d8194285497d94a10f9f21fb..92b8aea3e0634aef4d5e858cd3baf84afd9afdaa 100644 (file)
--- a/drivers/iio/buffer/industrialio-triggered-buffer.c
+++ b/drivers/iio/buffer/industrialio-triggered-buffer.c
@@ -9,18 +9,20 @@
 #include <linux/module.h>
 #include <linux/iio/iio.h>
 #include <linux/iio/buffer.h>
+#include <linux/iio/buffer_impl.h>
 #include <linux/iio/kfifo_buf.h>
 #include <linux/iio/triggered_buffer.h>
 #include <linux/iio/trigger_consumer.h>
 
 /**
- * iio_triggered_buffer_setup() - Setup triggered buffer and pollfunc
+ * iio_triggered_buffer_setup_ext() - Setup triggered buffer and pollfunc
  * @indio_dev:         IIO device structure
  * @h:                 Function which will be used as pollfunc top half
  * @thread:            Function which will be used as pollfunc bottom half
  * @setup_ops:         Buffer setup functions to use for this device.
  *                     If NULL the default setup functions for triggered
  *                     buffers will be used.
+ * @buffer_attrs:      Extra sysfs buffer attributes for this IIO buffer
  *
  * This function combines some common tasks which will normally be performed
  * when setting up a triggered buffer. It will allocate the buffer and the
@@ -33,10 +35,11 @@
  * To free the resources allocated by this function call
  * iio_triggered_buffer_cleanup().
  */
-int iio_triggered_buffer_setup(struct iio_dev *indio_dev,
+int iio_triggered_buffer_setup_ext(struct iio_dev *indio_dev,
        irqreturn_t (*h)(int irq, void *p),
        irqreturn_t (*thread)(int irq, void *p),
-       const struct iio_buffer_setup_ops *setup_ops)
+       const struct iio_buffer_setup_ops *setup_ops,
+       const struct attribute **buffer_attrs)
 {
        struct iio_buffer *buffer;
        int ret;
@@ -67,6 +70,8 @@ int iio_triggered_buffer_setup(struct iio_dev *indio_dev,
        /* Flag that polled ring buffering is possible */
        indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
 
+       buffer->attrs = buffer_attrs;
+
        return 0;
 
 error_kfifo_free:
@@ -74,10 +79,10 @@ error_kfifo_free:
 error_ret:
        return ret;
 }
-EXPORT_SYMBOL(iio_triggered_buffer_setup);
+EXPORT_SYMBOL(iio_triggered_buffer_setup_ext);
 
 /**
- * iio_triggered_buffer_cleanup() - Free resources allocated by iio_triggered_buffer_setup()
+ * iio_triggered_buffer_cleanup() - Free resources allocated by iio_triggered_buffer_setup_ext()
  * @indio_dev: IIO device structure
  */
 void iio_triggered_buffer_cleanup(struct iio_dev *indio_dev)
@@ -92,11 +97,12 @@ static void devm_iio_triggered_buffer_clean(struct device *dev, void *res)
        iio_triggered_buffer_cleanup(*(struct iio_dev **)res);
 }
 
-int devm_iio_triggered_buffer_setup(struct device *dev,
-                                   struct iio_dev *indio_dev,
-                                   irqreturn_t (*h)(int irq, void *p),
-                                   irqreturn_t (*thread)(int irq, void *p),
-                                   const struct iio_buffer_setup_ops *ops)
+int devm_iio_triggered_buffer_setup_ext(struct device *dev,
+                                       struct iio_dev *indio_dev,
+                                       irqreturn_t (*h)(int irq, void *p),
+                                       irqreturn_t (*thread)(int irq, void *p),
+                                       const struct iio_buffer_setup_ops *ops,
+                                       const struct attribute **buffer_attrs)
 {
        struct iio_dev **ptr;
        int ret;
@@ -108,7 +114,8 @@ int devm_iio_triggered_buffer_setup(struct device *dev,
 
        *ptr = indio_dev;
 
-       ret = iio_triggered_buffer_setup(indio_dev, h, thread, ops);
+       ret = iio_triggered_buffer_setup_ext(indio_dev, h, thread, ops,
+                                            buffer_attrs);
        if (!ret)
                devres_add(dev, ptr);
        else
@@ -116,7 +123,7 @@ int devm_iio_triggered_buffer_setup(struct device *dev,
 
        return ret;
 }
-EXPORT_SYMBOL_GPL(devm_iio_triggered_buffer_setup);
+EXPORT_SYMBOL_GPL(devm_iio_triggered_buffer_setup_ext);
 
 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 MODULE_DESCRIPTION("IIO helper functions for setting up triggered buffers");

diff --git a/include/linux/iio/triggered_buffer.h b/include/linux/iio/triggered_buffer.h
index e99c91799359a176036ff7be5b1042d61794cd9f..7f154d1f8739c04e2113440f5a83c42a707d49da 100644 (file)
--- a/include/linux/iio/triggered_buffer.h
+++ b/include/linux/iio/triggered_buffer.h
@@ -4,19 +4,28 @@
 
 #include <linux/interrupt.h>
 
+struct attribute;
 struct iio_dev;
 struct iio_buffer_setup_ops;
 
-int iio_triggered_buffer_setup(struct iio_dev *indio_dev,
+int iio_triggered_buffer_setup_ext(struct iio_dev *indio_dev,
        irqreturn_t (*h)(int irq, void *p),
        irqreturn_t (*thread)(int irq, void *p),
-       const struct iio_buffer_setup_ops *setup_ops);
+       const struct iio_buffer_setup_ops *setup_ops,
+       const struct attribute **buffer_attrs);
 void iio_triggered_buffer_cleanup(struct iio_dev *indio_dev);
 
-int devm_iio_triggered_buffer_setup(struct device *dev,
-                                   struct iio_dev *indio_dev,
-                                   irqreturn_t (*h)(int irq, void *p),
-                                   irqreturn_t (*thread)(int irq, void *p),
-                                   const struct iio_buffer_setup_ops *ops);
+#define iio_triggered_buffer_setup(indio_dev, h, thread, setup_ops)            \
+       iio_triggered_buffer_setup_ext((indio_dev), (h), (thread), (setup_ops), NULL)
+
+int devm_iio_triggered_buffer_setup_ext(struct device *dev,
+                                       struct iio_dev *indio_dev,
+                                       irqreturn_t (*h)(int irq, void *p),
+                                       irqreturn_t (*thread)(int irq, void *p),
+                                       const struct iio_buffer_setup_ops *ops,
+                                       const struct attribute **buffer_attrs);
+
+#define devm_iio_triggered_buffer_setup(dev, indio_dev, h, thread, setup_ops)  \
+       devm_iio_triggered_buffer_setup_ext((dev), (indio_dev), (h), (thread), (setup_ops), NULL)
 
 #endif