5 May
2014
5 May
'14
1:40 a.m.
On 05/04/2014 06:41 PM, Chris Wilson wrote:
On Sun, May 04, 2014 at 03:31:01PM +0800, Aaron Lu wrote:
On 05/04/2014 03:22 PM, Chris Wilson wrote:
Also this still has the same rounding error as before.
I didn't get this, care to explain?
The calculation you use, truncates, rather than say round to nearest, would is the same discrepancy in your changelog.
This patch is meant to fix the problem that when user specify the max backlight level in acpi_video interface, we will get the hardware max level too in i915. With this patch, the hardware level we will get is: level * freq / max = 255 * 937 / 255 = 937, which is correct.
For other values, the truncates is OK: 254 * 937 / 255 = 933 253 * 937 / 255 = 929 ... ...