On 10/9/23 17:02, Dmitry Rokosov wrote:
On Mon, Oct 09, 2023 at 04:18:08PM +0300, Dmitry Rokosov wrote:
On Fri, Oct 06, 2023 at 09:03:47PM +0300, Andy Shevchenko wrote:
On Fri, Oct 6, 2023 at 7:05 PM Dmitry Rokosov
<ddrokosov@xxxxxxxxxxxxxxxxx> wrote:
From: George Stark <gnstark@xxxxxxxxxxxxxxxxx>
use DIV_ROUND_UP instead of coarse div
Please, respect English grammar and punctuation.
Refer to macros and functions as func() (note the parentheses).
...
#define AW200XX_REG_DIM2FADE(x) ((x) + 1)
+#define AW200XX_REG_FADE2DIM(fade) \
+ DIV_ROUND_UP((fade) * AW200XX_DIM_MAX, AW200XX_FADE_MAX)
Have you checked if the overflow is _now_ possible (compiling on
32-bit platforms as well)?
I suppose we shouldn't carry on about overflow here because the value of
fade cannot exceed 255, and DIM_MAX is set at 63
You can find maximum values of fade and dim in the aw200xx driver
header:
#define AW200XX_DIM_MAX (BIT(6) - 1)
#define AW200XX_FADE_MAX (BIT(8) - 1)
I agree that checking if the fade is not greater than FADE_MAX will not
be excessive. The LED subsystem is capable of sending brightness levels
higher than 255
Probably we should set max_brightness to AW200XX_FADE_MAX in
led_classdev when adding leds.
--
Best regards
George
