iio: buffer: Drop get_length callback

We already do have the length field in the struct iio_buffer which is
expected to be in sync with the current size of the buffer. And currently
all implementations of the get_length callback either return this field or a
constant number.

This patch removes the get_length callback and replaces all occurrences in
the IIO core with directly accessing the length field of the buffer.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index 4ca4c0a..2bd8d39 100644 (file)
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -390,11 +390,7 @@ static ssize_t iio_buffer_read_length(struct device *dev,
        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
        struct iio_buffer *buffer = indio_dev->buffer;
 
-       if (buffer->access->get_length)
-               return sprintf(buf, "%d\n",
-                              buffer->access->get_length(buffer));
-
-       return 0;
+       return sprintf(buf, "%d\n", buffer->length);
 }
 
 static ssize_t iio_buffer_write_length(struct device *dev,
@@ -410,9 +406,8 @@ static ssize_t iio_buffer_write_length(struct device *dev,
        if (ret)
                return ret;
 
-       if (buffer->access->get_length)
-               if (val == buffer->access->get_length(buffer))
-                       return len;
+       if (val == buffer->length)
+               return len;
 
        mutex_lock(&indio_dev->mlock);
        if (iio_buffer_is_active(indio_dev->buffer)) {

diff --git a/drivers/iio/kfifo_buf.c b/drivers/iio/kfifo_buf.c
index 3b0a3bc..b20a9cf 100644 (file)
--- a/drivers/iio/kfifo_buf.c
+++ b/drivers/iio/kfifo_buf.c
@@ -47,11 +47,6 @@ static int iio_request_update_kfifo(struct iio_buffer *r)
        return ret;
 }
 
-static int iio_get_length_kfifo(struct iio_buffer *r)
-{
-       return r->length;
-}
-
 static int iio_mark_update_needed_kfifo(struct iio_buffer *r)
 {
        struct iio_kfifo *kf = iio_to_kfifo(r);
@@ -141,7 +136,6 @@ static const struct iio_buffer_access_funcs kfifo_access_funcs = {
        .data_available = iio_kfifo_buf_data_available,
        .request_update = &iio_request_update_kfifo,
        .set_bytes_per_datum = &iio_set_bytes_per_datum_kfifo,
-       .get_length = &iio_get_length_kfifo,
        .set_length = &iio_set_length_kfifo,
        .release = &iio_kfifo_buffer_release,
 };

diff --git a/drivers/staging/iio/Documentation/ring.txt b/drivers/staging/iio/Documentation/ring.txt
index 434d63a..18718fc 100644 (file)
--- a/drivers/staging/iio/Documentation/ring.txt
+++ b/drivers/staging/iio/Documentation/ring.txt
@@ -42,6 +42,6 @@ request_update
 set_bytes_per_datum
   Set the number of bytes for a complete scan. (All samples + timestamp)
 
-get_length / set_length
-  Get/set the number of complete scans that may be held by the buffer.
+set_length
+  Set the number of complete scans that may be held by the buffer.
 

diff --git a/drivers/staging/iio/accel/sca3000_ring.c b/drivers/staging/iio/accel/sca3000_ring.c
index f2f260e..f76a268 100644 (file)
--- a/drivers/staging/iio/accel/sca3000_ring.c
+++ b/drivers/staging/iio/accel/sca3000_ring.c
@@ -129,12 +129,6 @@ error_ret:
        return ret ? ret : num_read;
 }
 
-/* This is only valid with all 3 elements enabled */
-static int sca3000_ring_get_length(struct iio_buffer *r)
-{
-       return 64;
-}
-
 static bool sca3000_ring_buf_data_available(struct iio_buffer *r)
 {
        return r->stufftoread;
@@ -248,6 +242,7 @@ static struct iio_buffer *sca3000_rb_allocate(struct iio_dev *indio_dev)
        ring->private = indio_dev;
        buf = &ring->buf;
        buf->stufftoread = 0;
+       buf->length = 64;
        buf->attrs = sca3000_ring_attributes;
        iio_buffer_init(buf);
 
@@ -261,7 +256,6 @@ static void sca3000_ring_release(struct iio_buffer *r)
 
 static const struct iio_buffer_access_funcs sca3000_ring_access_funcs = {
        .read_first_n = &sca3000_read_first_n_hw_rb,
-       .get_length = &sca3000_ring_get_length,
        .data_available = sca3000_ring_buf_data_available,
        .release = sca3000_ring_release,
 };

diff --git a/include/linux/iio/buffer.h b/include/linux/iio/buffer.h
index 16b7663..b65850a 100644 (file)
--- a/include/linux/iio/buffer.h
+++ b/include/linux/iio/buffer.h
@@ -26,7 +26,6 @@ struct iio_buffer;
  * @request_update:    if a parameter change has been marked, update underlying
  *                     storage.
  * @set_bytes_per_datum:set number of bytes per datum
- * @get_length:                get number of datums in buffer
  * @set_length:                set number of datums in buffer
  * @release:           called when the last reference to the buffer is dropped,
  *                     should free all resources allocated by the buffer.
@@ -49,7 +48,6 @@ struct iio_buffer_access_funcs {
        int (*request_update)(struct iio_buffer *buffer);
 
        int (*set_bytes_per_datum)(struct iio_buffer *buffer, size_t bpd);
-       int (*get_length)(struct iio_buffer *buffer);
        int (*set_length)(struct iio_buffer *buffer, int length);
 
        void (*release)(struct iio_buffer *buffer);