[PATCH] iio: xilinx-ams: Don't include ams_ctrl_channels in scan_mask

From: Sean Anderson
Date: Mon Mar 11 2024 - 12:31:27 EST


ams_enable_channel_sequence constructs a "scan_mask" for all the PS and
PL channels. This works out fine, since scan_index for these channels is
less than 64. However, it also includes the ams_ctrl_channels, where
scan_index is greater than 64, triggering undefined behavior. Since we
don't need these channels anyway, just exclude them.

Fixes: d5c70627a794 ("iio: adc: Add Xilinx AMS driver")
Signed-off-by: Sean Anderson <sean.anderson@xxxxxxxxx>
---

drivers/iio/adc/xilinx-ams.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/adc/xilinx-ams.c b/drivers/iio/adc/xilinx-ams.c
index a55396c1f8b2..4de7ce598e4d 100644
--- a/drivers/iio/adc/xilinx-ams.c
+++ b/drivers/iio/adc/xilinx-ams.c
@@ -414,8 +414,12 @@ static void ams_enable_channel_sequence(struct iio_dev *indio_dev)

/* Run calibration of PS & PL as part of the sequence */
scan_mask = BIT(0) | BIT(AMS_PS_SEQ_MAX);
- for (i = 0; i < indio_dev->num_channels; i++)
- scan_mask |= BIT_ULL(indio_dev->channels[i].scan_index);
+ for (i = 0; i < indio_dev->num_channels; i++) {
+ const struct iio_chan_spec *chan = &indio_dev->channels[i];
+
+ if (chan->scan_index < AMS_CTRL_SEQ_BASE)
+ scan_mask |= BIT_ULL(chan->scan_index);
+ }

if (ams->ps_base) {
/* put sysmon in a soft reset to change the sequence */
--
2.35.1.1320.gc452695387.dirty