staging:iio:adc:ad7887 make use of iio_sw_buffer_preenable.

Using this generic function cuts down on repeated code at the cost
of some computation in a slow path.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/iio/adc/ad7887.h b/drivers/staging/iio/adc/ad7887.h
index bc53b65..2e09e54 100644 (file)
--- a/drivers/staging/iio/adc/ad7887.h
+++ b/drivers/staging/iio/adc/ad7887.h
@@ -63,7 +63,6 @@ struct ad7887_state {
        struct spi_device               *spi;
        const struct ad7887_chip_info   *chip_info;
        struct regulator                *reg;
-       size_t                          d_size;
        u16                             int_vref_mv;
        struct spi_transfer             xfer[4];
        struct spi_message              msg[3];

diff --git a/drivers/staging/iio/adc/ad7887_ring.c b/drivers/staging/iio/adc/ad7887_ring.c
index d180907..442994e 100644 (file)
--- a/drivers/staging/iio/adc/ad7887_ring.c
+++ b/drivers/staging/iio/adc/ad7887_ring.c
@@ -29,22 +29,11 @@
 static int ad7887_ring_preenable(struct iio_dev *indio_dev)
 {
        struct ad7887_state *st = iio_priv(indio_dev);
-       struct iio_buffer *ring = indio_dev->buffer;
-
-       st->d_size = bitmap_weight(indio_dev->active_scan_mask,
-                                  indio_dev->masklength) *
-               st->chip_info->channel[0].scan_type.storagebits / 8;
-
-       if (ring->scan_timestamp) {
-               st->d_size += sizeof(s64);
-
-               if (st->d_size % sizeof(s64))
-                       st->d_size += sizeof(s64) - (st->d_size % sizeof(s64));
-       }
+       int ret;
 
-       if (indio_dev->buffer->access->set_bytes_per_datum)
-               indio_dev->buffer->access->
-                       set_bytes_per_datum(indio_dev->buffer, st->d_size);
+       ret = iio_sw_buffer_preenable(indio_dev);
+       if (ret < 0)
+               return ret;
 
        /* We know this is a single long so can 'cheat' */
        switch (*indio_dev->active_scan_mask) {
@@ -92,7 +81,7 @@ static irqreturn_t ad7887_trigger_handler(int irq, void *p)
                                           indio_dev->masklength) *
                st->chip_info->channel[0].scan_type.storagebits / 8;
 
-       buf = kzalloc(st->d_size, GFP_KERNEL);
+       buf = kzalloc(indio_dev->scan_bytes, GFP_KERNEL);
        if (buf == NULL)
                return -ENOMEM;
 
@@ -104,7 +93,7 @@ static irqreturn_t ad7887_trigger_handler(int irq, void *p)
 
        memcpy(buf, st->data, bytes);
        if (ring->scan_timestamp)
-               memcpy(buf + st->d_size - sizeof(s64),
+               memcpy(buf + indio_dev->scan_bytes - sizeof(s64),
                       &time_ns, sizeof(time_ns));
 
        indio_dev->buffer->access->store_to(indio_dev->buffer, buf, time_ns);