staging:iio:adc:ad7280a: Split buff[2] into tx and rx parts

As the __cacheline_aligned will ensure that the first of these two buffers
is appropriate aligned, there is no need to keep them as a single array
which is confusing given the first element is always tx and the second
rx.  Hence let us just have two parts and name them separately.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Marcelo Schmitt <marcelo.schmitt1@gmail.com>
Link: https://lore.kernel.org/r/20220206190328.333093-5-jic23@kernel.org
This commit is contained in:
Jonathan Cameron 2022-02-06 19:03:12 +00:00
parent dd7062fe88
commit 003f1d48de

View file

@ -153,7 +153,8 @@ struct ad7280_state {
unsigned char cb_mask[AD7280A_MAX_CHAIN];
struct mutex lock; /* protect sensor state */
__be32 buf[2] ____cacheline_aligned;
__be32 tx ____cacheline_aligned;
__be32 rx;
};
static unsigned char ad7280_calc_crc8(unsigned char *crc_tab, unsigned int val)
@ -196,18 +197,18 @@ static int __ad7280_read32(struct ad7280_state *st, unsigned int *val)
{
int ret;
struct spi_transfer t = {
.tx_buf = &st->buf[0],
.rx_buf = &st->buf[1],
.len = 4,
.tx_buf = &st->tx,
.rx_buf = &st->rx,
.len = sizeof(st->tx),
};
st->buf[0] = cpu_to_be32(AD7280A_READ_TXVAL);
st->tx = cpu_to_be32(AD7280A_READ_TXVAL);
ret = spi_sync_transfer(st->spi, &t, 1);
if (ret)
return ret;
*val = be32_to_cpu(st->buf[1]);
*val = be32_to_cpu(st->rx);
return 0;
}
@ -219,9 +220,9 @@ static int ad7280_write(struct ad7280_state *st, unsigned int devaddr,
(val & 0xFF) << 13 | all << 12;
reg |= ad7280_calc_crc8(st->crc_tab, reg >> 11) << 3 | 0x2;
st->buf[0] = cpu_to_be32(reg);
st->tx = cpu_to_be32(reg);
return spi_write(st->spi, &st->buf[0], 4);
return spi_write(st->spi, &st->tx, sizeof(st->tx));
}
static int ad7280_read_reg(struct ad7280_state *st, unsigned int devaddr,