diff options
| author | Dragos Bogdan <dragos.bogdan@analog.com> | 2020-04-29 10:21:29 +0300 |
|---|---|---|
| committer | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2020-05-03 12:35:03 +0100 |
| commit | 5e4f99a6b788047b0b8a7496c2e0c8f372f6edf2 (patch) | |
| tree | 1920a89718d5fdb07ced83a470358dcb65edf6cb /drivers/staging/iio | |
| parent | aad4742fbf0a560c25827adb58695a4497ffc204 (diff) | |
| download | linux-5e4f99a6b788047b0b8a7496c2e0c8f372f6edf2.tar.bz2 | |
staging: iio: ad2s1210: Fix SPI reading
If the serial interface is used, the 8-bit address should be latched using
the rising edge of the WR/FSYNC signal.
This basically means that a CS change is required between the first byte
sent, and the second one.
This change splits the single-transfer transfer of 2 bytes into 2 transfers
with a single byte, and CS change in-between.
Note fixes tag is not accurate, but reflects a point beyond which there
are too many refactors to make backporting straight forward.
Fixes: b19e9ad5e2cb ("staging:iio:resolver:ad2s1210 general driver cleanup.")
Signed-off-by: Dragos Bogdan <dragos.bogdan@analog.com>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'drivers/staging/iio')
| -rw-r--r-- | drivers/staging/iio/resolver/ad2s1210.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/drivers/staging/iio/resolver/ad2s1210.c b/drivers/staging/iio/resolver/ad2s1210.c index 4b25a3a314ed..ed404355ea4c 100644 --- a/drivers/staging/iio/resolver/ad2s1210.c +++ b/drivers/staging/iio/resolver/ad2s1210.c @@ -130,17 +130,24 @@ static int ad2s1210_config_write(struct ad2s1210_state *st, u8 data) static int ad2s1210_config_read(struct ad2s1210_state *st, unsigned char address) { - struct spi_transfer xfer = { - .len = 2, - .rx_buf = st->rx, - .tx_buf = st->tx, + struct spi_transfer xfers[] = { + { + .len = 1, + .rx_buf = &st->rx[0], + .tx_buf = &st->tx[0], + .cs_change = 1, + }, { + .len = 1, + .rx_buf = &st->rx[1], + .tx_buf = &st->tx[1], + }, }; int ret = 0; ad2s1210_set_mode(MOD_CONFIG, st); st->tx[0] = address | AD2S1210_MSB_IS_HIGH; st->tx[1] = AD2S1210_REG_FAULT; - ret = spi_sync_transfer(st->sdev, &xfer, 1); + ret = spi_sync_transfer(st->sdev, xfers, 2); if (ret < 0) return ret; |