iio: mxs-lradc: convert is_divided to a bitmap

mxs_lradc.is_divided was an unsigned long array. Convert it to a bitmap to save
some memory.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/staging/iio/adc/mxs-lradc.c b/drivers/staging/iio/adc/mxs-lradc.c
index a58c6aaa94d357cda7a05179ef97ded8cc5cf2e8..df71669bb60ea51be793903d7a62df399e388c55 100644 (file)
--- a/drivers/staging/iio/adc/mxs-lradc.c
+++ b/drivers/staging/iio/adc/mxs-lradc.c
@@ -211,7 +211,7 @@ struct mxs_lradc {
 
        const uint32_t          *vref_mv;
        struct mxs_lradc_scale  scale_avail[LRADC_MAX_TOTAL_CHANS][2];
-       unsigned int            is_divided[LRADC_MAX_TOTAL_CHANS];
+       unsigned long           is_divided;
 
        /*
         * Touchscreen LRADC channels receives a private slot in the CTRL4
@@ -920,7 +920,7 @@ static int mxs_lradc_read_raw(struct iio_dev *iio_dev,
 
                *val = lradc->vref_mv[chan->channel];
                *val2 = chan->scan_type.realbits -
-                       lradc->is_divided[chan->channel];
+                       test_bit(chan->channel, &lradc->is_divided);
                return IIO_VAL_FRACTIONAL_LOG2;
 
        case IIO_CHAN_INFO_OFFSET:
@@ -965,14 +965,14 @@ static int mxs_lradc_write_raw(struct iio_dev *iio_dev,
                        /* divider by two disabled */
                        writel(1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
                               lradc->base + LRADC_CTRL2 + STMP_OFFSET_REG_CLR);
-                       lradc->is_divided[chan->channel] = 0;
+                       clear_bit(chan->channel, &lradc->is_divided);
                        ret = 0;
                } else if (val == scale_avail[MXS_LRADC_DIV_ENABLED].integer &&
                           val2 == scale_avail[MXS_LRADC_DIV_ENABLED].nano) {
                        /* divider by two enabled */
                        writel(1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
                               lradc->base + LRADC_CTRL2 + STMP_OFFSET_REG_SET);
-                       lradc->is_divided[chan->channel] = 1;
+                       set_bit(chan->channel, &lradc->is_divided);
                        ret = 0;
                }