Staging: iio: ring_sw.c: fix up sparse warnings

NULL usage, static stuff, etc.

Cc: 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 5ee3e45..1f14cd4 100644 (file)
--- a/drivers/staging/iio/ring_sw.c
+++ b/drivers/staging/iio/ring_sw.c
@@ -21,10 +21,10 @@ static inline int __iio_allocate_sw_ring_buffer(struct iio_sw_ring_buffer *ring,
                return -EINVAL;
        __iio_update_ring_buffer(&ring->buf, bytes_per_datum, length);
        ring->data = kmalloc(length*ring->buf.bpd, GFP_KERNEL);
-       ring->read_p = 0;
-       ring->write_p = 0;
-       ring->last_written_p = 0;
-       ring->half_p = 0;
+       ring->read_p = NULL;
+       ring->write_p = NULL;
+       ring->last_written_p = NULL;
+       ring->half_p = NULL;
        return ring->data ? 0 : -ENOMEM;
 }
 
@@ -62,16 +62,15 @@ EXPORT_SYMBOL(iio_unmark_sw_rb_in_use);
  * in the device driver */
 /* Lock always held if their is a chance this may be called */
 /* Only one of these per ring may run concurrently - enforced by drivers */
-int iio_store_to_sw_ring(struct iio_sw_ring_buffer *ring,
-                        unsigned char *data,
-                        s64 timestamp)
+static int iio_store_to_sw_ring(struct iio_sw_ring_buffer *ring,
+                               unsigned char *data, s64 timestamp)
 {
        int ret = 0;
        int code;
        unsigned char *temp_ptr, *change_test_ptr;
 
        /* initial store */
-       if (unlikely(ring->write_p == 0)) {
+       if (unlikely(ring->write_p == NULL)) {
                ring->write_p = ring->data;
                /* Doesn't actually matter if this is out of the set
                 * as long as the read pointer is valid before this
@@ -102,7 +101,7 @@ int iio_store_to_sw_ring(struct iio_sw_ring_buffer *ring,
         */
        ring->write_p = temp_ptr;
 
-       if (ring->read_p == 0)
+       if (ring->read_p == NULL)
                ring->read_p = ring->data;
        /* Buffer full - move the read pointer and create / escalate
         * ring event */
@@ -182,7 +181,7 @@ int iio_rip_sw_rb(struct iio_ring_buffer *r,
 
        /* build local copy */
        initial_read_p = ring->read_p;
-       if (unlikely(initial_read_p == 0)) { /* No data here as yet */
+       if (unlikely(initial_read_p == NULL)) { /* No data here as yet */
                ret = 0;
                goto error_free_data_cpy;
        }
@@ -280,8 +279,8 @@ int iio_store_to_sw_rb(struct iio_ring_buffer *r, u8 *data, s64 timestamp)
 }
 EXPORT_SYMBOL(iio_store_to_sw_rb);
 
-int iio_read_last_from_sw_ring(struct iio_sw_ring_buffer *ring,
-                              unsigned char *data)
+static int iio_read_last_from_sw_ring(struct iio_sw_ring_buffer *ring,
+                                     unsigned char *data)
 {
        unsigned char *last_written_p_copy;
 
@@ -291,7 +290,7 @@ again:
        last_written_p_copy = ring->last_written_p;
        barrier(); /*unnessecary? */
        /* Check there is anything here */
-       if (last_written_p_copy == 0)
+       if (last_written_p_copy == NULL)
                return -EAGAIN;
        memcpy(data, last_written_p_copy, ring->buf.bpd);
 
@@ -412,7 +411,7 @@ struct iio_ring_buffer *iio_sw_rb_allocate(struct iio_dev *indio_dev)
 
        ring = kzalloc(sizeof *ring, GFP_KERNEL);
        if (!ring)
-               return 0;
+               return NULL;
        buf = &ring->buf;
        iio_ring_buffer_init(buf, indio_dev);
        __iio_init_sw_ring_buffer(ring);