staging:iio: rationalization of different buffer implementation hooks.
1) move a generic helper function out of ring_sw. It applies to other buffers as well.
2) Get rid of a lot of left over function definitions.
3) Move all the access functions into static structures.
4) Introduce and use a static structure for the setup functions, preenable etc.
Some driver conversions thanks to Michael Hennerich (pulled out of patches
that would otherwise sit after this).
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/staging/iio/ring_sw.c b/drivers/staging/iio/ring_sw.c
index d55757b..35896cbb 100644
--- a/drivers/staging/iio/ring_sw.c
+++ b/drivers/staging/iio/ring_sw.c
@@ -17,6 +17,36 @@
#include "ring_sw.h"
#include "trigger.h"
+/**
+ * struct iio_sw_ring_buffer - software ring buffer
+ * @buf: generic ring buffer elements
+ * @data: the ring buffer memory
+ * @read_p: read pointer (oldest available)
+ * @write_p: write pointer
+ * @last_written_p: read pointer (newest available)
+ * @half_p: half buffer length behind write_p (event generation)
+ * @use_count: reference count to prevent resizing when in use
+ * @update_needed: flag to indicated change in size requested
+ * @use_lock: lock to prevent change in size when in use
+ *
+ * Note that the first element of all ring buffers must be a
+ * struct iio_ring_buffer.
+**/
+struct iio_sw_ring_buffer {
+ struct iio_ring_buffer buf;
+ unsigned char *data;
+ unsigned char *read_p;
+ unsigned char *write_p;
+ unsigned char *last_written_p;
+ /* used to act as a point at which to signal an event */
+ unsigned char *half_p;
+ int use_count;
+ int update_needed;
+ spinlock_t use_lock;
+};
+
+#define iio_to_sw_ring(r) container_of(r, struct iio_sw_ring_buffer, buf)
+
static inline int __iio_allocate_sw_ring_buffer(struct iio_sw_ring_buffer *ring,
int bytes_per_datum, int length)
{
@@ -41,23 +71,21 @@
kfree(ring->data);
}
-void iio_mark_sw_rb_in_use(struct iio_ring_buffer *r)
+static void iio_mark_sw_rb_in_use(struct iio_ring_buffer *r)
{
struct iio_sw_ring_buffer *ring = iio_to_sw_ring(r);
spin_lock(&ring->use_lock);
ring->use_count++;
spin_unlock(&ring->use_lock);
}
-EXPORT_SYMBOL(iio_mark_sw_rb_in_use);
-void iio_unmark_sw_rb_in_use(struct iio_ring_buffer *r)
+static void iio_unmark_sw_rb_in_use(struct iio_ring_buffer *r)
{
struct iio_sw_ring_buffer *ring = iio_to_sw_ring(r);
spin_lock(&ring->use_lock);
ring->use_count--;
spin_unlock(&ring->use_lock);
}
-EXPORT_SYMBOL(iio_unmark_sw_rb_in_use);
/* Ring buffer related functionality */
@@ -138,8 +166,8 @@
return ret;
}
-int iio_read_first_n_sw_rb(struct iio_ring_buffer *r,
- size_t n, char __user *buf)
+static int iio_read_first_n_sw_rb(struct iio_ring_buffer *r,
+ size_t n, char __user *buf)
{
struct iio_sw_ring_buffer *ring = iio_to_sw_ring(r);
@@ -268,14 +296,14 @@
return ret;
}
-EXPORT_SYMBOL(iio_read_first_n_sw_rb);
-int iio_store_to_sw_rb(struct iio_ring_buffer *r, u8 *data, s64 timestamp)
+static int iio_store_to_sw_rb(struct iio_ring_buffer *r,
+ u8 *data,
+ s64 timestamp)
{
struct iio_sw_ring_buffer *ring = iio_to_sw_ring(r);
return iio_store_to_sw_ring(ring, data, timestamp);
}
-EXPORT_SYMBOL(iio_store_to_sw_rb);
static int iio_read_last_from_sw_ring(struct iio_sw_ring_buffer *ring,
unsigned char *data)
@@ -299,14 +327,13 @@
return 0;
}
-int iio_read_last_from_sw_rb(struct iio_ring_buffer *r,
+static int iio_read_last_from_sw_rb(struct iio_ring_buffer *r,
unsigned char *data)
{
return iio_read_last_from_sw_ring(iio_to_sw_ring(r), data);
}
-EXPORT_SYMBOL(iio_read_last_from_sw_rb);
-int iio_request_update_sw_rb(struct iio_ring_buffer *r)
+static int iio_request_update_sw_rb(struct iio_ring_buffer *r)
{
int ret = 0;
struct iio_sw_ring_buffer *ring = iio_to_sw_ring(r);
@@ -326,50 +353,44 @@
spin_unlock(&ring->use_lock);
return ret;
}
-EXPORT_SYMBOL(iio_request_update_sw_rb);
-int iio_get_bytes_per_datum_sw_rb(struct iio_ring_buffer *r)
+static int iio_get_bytes_per_datum_sw_rb(struct iio_ring_buffer *r)
{
struct iio_sw_ring_buffer *ring = iio_to_sw_ring(r);
return ring->buf.bytes_per_datum;
}
-EXPORT_SYMBOL(iio_get_bytes_per_datum_sw_rb);
-int iio_set_bytes_per_datum_sw_rb(struct iio_ring_buffer *r, size_t bpd)
+static int iio_set_bytes_per_datum_sw_rb(struct iio_ring_buffer *r, size_t bpd)
{
if (r->bytes_per_datum != bpd) {
r->bytes_per_datum = bpd;
- if (r->access.mark_param_change)
- r->access.mark_param_change(r);
+ if (r->access->mark_param_change)
+ r->access->mark_param_change(r);
}
return 0;
}
-EXPORT_SYMBOL(iio_set_bytes_per_datum_sw_rb);
-int iio_get_length_sw_rb(struct iio_ring_buffer *r)
+static int iio_get_length_sw_rb(struct iio_ring_buffer *r)
{
return r->length;
}
-EXPORT_SYMBOL(iio_get_length_sw_rb);
-int iio_set_length_sw_rb(struct iio_ring_buffer *r, int length)
+static int iio_set_length_sw_rb(struct iio_ring_buffer *r, int length)
{
if (r->length != length) {
r->length = length;
- if (r->access.mark_param_change)
- r->access.mark_param_change(r);
+ if (r->access->mark_param_change)
+ r->access->mark_param_change(r);
}
return 0;
}
-EXPORT_SYMBOL(iio_set_length_sw_rb);
-int iio_mark_update_needed_sw_rb(struct iio_ring_buffer *r)
+static int iio_mark_update_needed_sw_rb(struct iio_ring_buffer *r)
{
struct iio_sw_ring_buffer *ring = iio_to_sw_ring(r);
ring->update_needed = true;
return 0;
}
-EXPORT_SYMBOL(iio_mark_update_needed_sw_rb);
static void iio_sw_rb_release(struct device *dev)
{
@@ -412,6 +433,7 @@
ring = kzalloc(sizeof *ring, GFP_KERNEL);
if (!ring)
return NULL;
+ ring->update_needed = true;
buf = &ring->buf;
iio_ring_buffer_init(buf, indio_dev);
__iio_init_sw_ring_buffer(ring);
@@ -430,36 +452,11 @@
}
EXPORT_SYMBOL(iio_sw_rb_free);
-int iio_sw_ring_preenable(struct iio_dev *indio_dev)
-{
- struct iio_ring_buffer *ring = indio_dev->ring;
- size_t size;
- dev_dbg(&indio_dev->dev, "%s\n", __func__);
- /* Check if there are any scan elements enabled, if not fail*/
- if (!(ring->scan_count || ring->scan_timestamp))
- return -EINVAL;
- if (ring->scan_timestamp)
- if (ring->scan_count)
- /* Timestamp (aligned to s64) and data */
- size = (((ring->scan_count * ring->bpe)
- + sizeof(s64) - 1)
- & ~(sizeof(s64) - 1))
- + sizeof(s64);
- else /* Timestamp only */
- size = sizeof(s64);
- else /* Data only */
- size = ring->scan_count * ring->bpe;
- ring->access.set_bytes_per_datum(ring, size);
-
- return 0;
-}
-EXPORT_SYMBOL(iio_sw_ring_preenable);
-
void iio_sw_trigger_to_ring(struct iio_sw_ring_helper_state *st)
{
struct iio_ring_buffer *ring = st->indio_dev->ring;
int len = 0;
- size_t datasize = ring->access.get_bytes_per_datum(ring);
+ size_t datasize = ring->access->get_bytes_per_datum(ring);
char *data = kmalloc(datasize, GFP_KERNEL);
if (data == NULL) {
@@ -476,7 +473,7 @@
*(s64 *)(((phys_addr_t)data + len
+ sizeof(s64) - 1) & ~(sizeof(s64) - 1))
= st->last_timestamp;
- ring->access.store_to(ring,
+ ring->access->store_to(ring,
(u8 *)data,
st->last_timestamp);
@@ -504,5 +501,20 @@
}
EXPORT_SYMBOL(iio_sw_poll_func_th);
+const struct iio_ring_access_funcs ring_sw_access_funcs = {
+ .mark_in_use = &iio_mark_sw_rb_in_use,
+ .unmark_in_use = &iio_unmark_sw_rb_in_use,
+ .store_to = &iio_store_to_sw_rb,
+ .read_last = &iio_read_last_from_sw_rb,
+ .read_first_n = &iio_read_first_n_sw_rb,
+ .mark_param_change = &iio_mark_update_needed_sw_rb,
+ .request_update = &iio_request_update_sw_rb,
+ .get_bytes_per_datum = &iio_get_bytes_per_datum_sw_rb,
+ .set_bytes_per_datum = &iio_set_bytes_per_datum_sw_rb,
+ .get_length = &iio_get_length_sw_rb,
+ .set_length = &iio_set_length_sw_rb,
+};
+EXPORT_SYMBOL(ring_sw_access_funcs);
+
MODULE_DESCRIPTION("Industrialio I/O software ring buffer");
MODULE_LICENSE("GPL");