Re: [PATCH] iio: temperature: mcp9600: Bound thresholds before scaling

[Andy Shevchenko <andriy.shevchenko@intel.com>]

On Mon, Nov 09, 2026 at 05:35:17PM +0800, Zhu Jun wrote:
> 
> mcp9600_write_thresh() multiplies the integer part by 1000000 before
> clamping to the supported temperature range. The multiplication can
> overflow int, so a request such as 3000 degrees can select the lower
> threshold instead of the upper threshold.
> 
> Clamp the integer part to the hot-junction range before scaling. Keep
> the existing final clamp for fractional values and the narrower cold-
> junction range.

...

> +		val = clamp_val(val, MCP9600_MIN_TEMP_HOT_JUNCTION_MICRO / 1000000,
> +				MCP9600_MAX_TEMP_HOT_JUNCTION_MICRO / 1000000);

Use MICRO from units.h (but be careful about sign.

>  		/* Scale value to include decimal part into calculations */
>  		s_val = (val < 0) ? ((val * 1000000) - val2) :
>  				    ((val * 1000000) + val2);

-- 
With Best Regards,
Andy Shevchenko