Coccinelle reported the following in both ad983x drivers:
do_div() does a 64-by-32 division, please consider using
div64_ul instead.

Fix this by replacing do_div() with div64_ul(), which
safely handles 64-bit dividends and unsigned long
divisors across all architectures.

Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com>
---
v2:
 - resent email with corrected addresses

 drivers/staging/iio/frequency/ad9832.c | 3 ++-
 drivers/staging/iio/frequency/ad9834.c | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/iio/frequency/ad9832.c b/drivers/staging/iio/frequency/ad9832.c
index b87ea1781b..61ee93263a 100644
--- a/drivers/staging/iio/frequency/ad9832.c
+++ b/drivers/staging/iio/frequency/ad9832.c
@@ -13,6 +13,7 @@
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/kernel.h>
+#include <linux/math64.h>
 #include <linux/module.h>
 #include <linux/regulator/consumer.h>
 #include <linux/slab.h>
@@ -115,7 +116,7 @@ static unsigned long ad9832_calc_freqreg(unsigned long mclk, unsigned long fout)
 {
 	unsigned long long freqreg = (u64)fout *
 				     (u64)((u64)1L << AD9832_FREQ_BITS);
-	do_div(freqreg, mclk);
+	freqreg = div64_ul(freqreg, mclk);
 	return freqreg;
 }
 
diff --git a/drivers/staging/iio/frequency/ad9834.c b/drivers/staging/iio/frequency/ad9834.c
index d339d5e8e0..83d0e1360c 100644
--- a/drivers/staging/iio/frequency/ad9834.c
+++ b/drivers/staging/iio/frequency/ad9834.c
@@ -10,6 +10,7 @@
 #include <linux/workqueue.h>
 #include <linux/device.h>
 #include <linux/kernel.h>
+#include <linux/math64.h>
 #include <linux/slab.h>
 #include <linux/sysfs.h>
 #include <linux/list.h>
@@ -101,7 +102,7 @@ static unsigned int ad9834_calc_freqreg(unsigned long mclk, unsigned long fout)
 {
 	unsigned long long freqreg = (u64)fout * (u64)BIT(AD9834_FREQ_BITS);
 
-	do_div(freqreg, mclk);
+	freqreg = div64_ul(freqreg, mclk);
 	return freqreg;
 }
 
-- 
2.47.3

On 4/9/26 10:01 AM, Joshua Crofts wrote:
> Coccinelle reported the following in both ad983x drivers:
> do_div() does a 64-by-32 division, please consider using
> div64_ul instead.
> 
> Fix this by replacing do_div() with div64_ul(), which
> safely handles 64-bit dividends and unsigned long
> divisors across all architectures.
> 
> Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com>
> ---
> v2:

Please don't send v2 or later revisions in reply to v1. It breaks
some workflows. Start a new thread instead.

>  - resent email with corrected addresses

Instead of a v2, you can just add a RESEND prefix to the subject line
in cases like this. But do include an explanation like this when you
do that.

> 
>  drivers/staging/iio/frequency/ad9832.c | 3 ++-
>  drivers/staging/iio/frequency/ad9834.c | 3 ++-
>  2 files changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/staging/iio/frequency/ad9832.c b/drivers/staging/iio/frequency/ad9832.c
> index b87ea1781b..61ee93263a 100644
> --- a/drivers/staging/iio/frequency/ad9832.c
> +++ b/drivers/staging/iio/frequency/ad9832.c
> @@ -13,6 +13,7 @@
>  #include <linux/device.h>
>  #include <linux/err.h>
>  #include <linux/kernel.h>
> +#include <linux/math64.h>
>  #include <linux/module.h>
>  #include <linux/regulator/consumer.h>
>  #include <linux/slab.h>
> @@ -115,7 +116,7 @@ static unsigned long ad9832_calc_freqreg(unsigned long mclk, unsigned long fout)
>  {
>  	unsigned long long freqreg = (u64)fout *
>  				     (u64)((u64)1L << AD9832_FREQ_BITS);

I would expect checkpatch to complain that there is no blank line
between variable declarations and the rest of the code here.

> -	do_div(freqreg, mclk);
> +	freqreg = div64_ul(freqreg, mclk);
>  	return freqreg;

We can just return directly now.

	return div64_ul(freqreg, mclk);

>  }
>  
> diff --git a/drivers/staging/iio/frequency/ad9834.c b/drivers/staging/iio/frequency/ad9834.c
> index d339d5e8e0..83d0e1360c 100644
> --- a/drivers/staging/iio/frequency/ad9834.c
> +++ b/drivers/staging/iio/frequency/ad9834.c
> @@ -10,6 +10,7 @@
>  #include <linux/workqueue.h>
>  #include <linux/device.h>
>  #include <linux/kernel.h>
> +#include <linux/math64.h>
>  #include <linux/slab.h>
>  #include <linux/sysfs.h>
>  #include <linux/list.h>
> @@ -101,7 +102,7 @@ static unsigned int ad9834_calc_freqreg(unsigned long mclk, unsigned long fout)
>  {
>  	unsigned long long freqreg = (u64)fout * (u64)BIT(AD9834_FREQ_BITS);
>  
> -	do_div(freqreg, mclk);
> +	freqreg = div64_ul(freqreg, mclk);
>  	return freqreg;

ditto.

>  }
>

On Thu, Apr 09, 2026 at 10:39:07AM -0500, David Lechner wrote:
> On 4/9/26 10:01 AM, Joshua Crofts wrote:
> > Coccinelle reported the following in both ad983x drivers:
> > do_div() does a 64-by-32 division, please consider using
> > div64_ul instead.
> > 
> > Fix this by replacing do_div() with div64_ul(), which
> > safely handles 64-bit dividends and unsigned long
> > divisors across all architectures.
> > 
> > Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com>
> > ---
> > v2:
> 
> Please don't send v2 or later revisions in reply to v1. It breaks
> some workflows. Start a new thread instead.

> >  - resent email with corrected addresses
> 
> Instead of a v2, you can just add a RESEND prefix to the subject line
> in cases like this. But do include an explanation like this when you
> do that.

Nevertheless my comments still applicable to v2. The also Documented
recommendation to avoid sending new versions earlier than 24h.

-- 
With Best Regards,
Andy Shevchenko