[PATCH 5.16 0659/1017] staging:iio:adc:ad7280a: Fix handing of device address bit reversing.

Greg Kroah-Hartman
2022-04-05T09:53:56Z

From: Jonathan Cameron <Jonathan.Cameron@huawei.com>

[ Upstream commit f281e4ddbbc0b60f061bc18a2834e9363ba85f9f ]

The bit reversal was wrong for bits 1 and 3 of the 5 bits.
Result is driver failure to probe if you have more than 2 daisy-chained
devices. Discovered via QEMU based device emulation.

Fixes tag is for when this moved from a macro to a function, but it
was broken before that.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Fixes: 065a7c0b1fec ("Staging: iio: adc: ad7280a.c: Fixed Macro argument reuse")
Reviewed-by: Marcelo Schmitt <marcelo.schmitt1@gmail.com>
Link: https://lore.kernel.org/r/20220206190328.333093-2-jic23@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/staging/iio/adc/ad7280a.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/iio/adc/ad7280a.c b/drivers/staging/iio/adc/ad7280a.c
index fef0055b8990..20183b2ea127 100644
--- a/drivers/staging/iio/adc/ad7280a.c
+++ b/drivers/staging/iio/adc/ad7280a.c
@@ -107,9 +107,9 @@
static unsigned int ad7280a_devaddr(unsigned int addr)
{
return ((addr & 0x1) << 4) |
- ((addr & 0x2) << 3) |
+ ((addr & 0x2) << 2) |
(addr & 0x4) |
- ((addr & 0x8) >> 3) |
+ ((addr & 0x8) >> 2) |
((addr & 0x10) >> 4);
}

--
2.34.1