linux-kernel - [PATCH] iio: adc: ad4000: don't use shift

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Message-Id: <20250702-iio-adc-ad4000-don-t-use-shift_right-v1-1-041c2d6c3950@baylibre.com>
Date: Wed, 02 Jul 2025 08:23:00 -0500
From: David Lechner <dlechner@...libre.com>
To: Marcelo Schmitt <marcelo.schmitt@...log.com>, 
 Lars-Peter Clausen <lars@...afoo.de>, 
 Michael Hennerich <Michael.Hennerich@...log.com>, 
 Jonathan Cameron <jic23@...nel.org>, 
 Nuno Sá <nuno.sa@...log.com>, 
 Andy Shevchenko <andy@...nel.org>
Cc: linux-iio@...r.kernel.org, linux-kernel@...r.kernel.org, 
 David Lechner <dlechner@...libre.com>
Subject: [PATCH] iio: adc: ad4000: don't use shift_right()

Drop use of shift_right() macro for unsigned value. The shift_right()
macro is intended for signed values and is not needed for unsigned
values.

This was found by a static analysis tool [1].

Link: https://github.com/analogdevicesinc/linux/pull/2831/files#diff-c14a34a6492576d22e7192cc0f61ad0083190aeb627191596fe12462f0c6f21aR557 [1]
Signed-off-by: David Lechner <dlechner@...libre.com>
---
 drivers/iio/adc/ad4000.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/adc/ad4000.c b/drivers/iio/adc/ad4000.c
index 5609a7845b6f50b5818613170df6b234f8f0c496..fd3d79fca78581e51bb904d0bcfeda3d3663ea25 100644
--- a/drivers/iio/adc/ad4000.c
+++ b/drivers/iio/adc/ad4000.c
@@ -554,7 +554,7 @@ static void ad4000_fill_scale_tbl(struct ad4000_state *st,
 	val = mult_frac(st->vref_mv, MICRO, st->gain_milli);
 
 	/* Would multiply by NANO here but we multiplied by extra MILLI */
-	tmp2 = shift_right((u64)val * MICRO, scale_bits);
+	tmp2 = (u64)val * MICRO >> scale_bits;
 	tmp0 = div_s64_rem(tmp2, NANO, &tmp1);
 
 	/* Store scale for when span compression is disabled */

---
base-commit: 6742eff60460e77158d4f1b233f17e0345c9e66a
change-id: 20250702-iio-adc-ad4000-don-t-use-shift_right-bda6e41152b6

Best regards,
-- 
David Lechner <dlechner@...libre.com>