The ad7124_soft_reset() function has the assumption that the chip will
assert the "power-on reset" bit in the STATUS register after a software
reset without any delay. The POR bit =0 is used to check if the chip
initialization is done.
A chip ID mismatch probe error appears intermittently when the probe
continues too soon and the ID register does not contain the expected
value.
Fix by adding a 200us delay after the software reset command is issued.
Fixes: b3af341bbd96 ("iio: adc: Add ad7124 support")
Signed-off-by: Dumitru Ceclan <dumitru.ceclan@xxxxxxxxxx>
Reviewed-by: Nuno Sa <nuno.sa@xxxxxxxxxx>
Link: https://patch.msgid.link/20240731-ad7124-fix-v1-1-46a76aa4b9be@xxxxxxxxxx
Cc: <Stable@xxxxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
diff --git a/drivers/iio/adc/ad7124.c b/drivers/iio/adc/ad7124.c
index 3beed78496c5..c0b82f64c976 100644
--- a/drivers/iio/adc/ad7124.c
+++ b/drivers/iio/adc/ad7124.c
@@ -764,6 +764,7 @@ static int ad7124_soft_reset(struct ad7124_state *st)
if (ret < 0)
return ret;
+ fsleep(200);
timeout = 100;
do {
ret = ad_sd_read_reg(&st->sd, AD7124_STATUS, 1, &readval);
