Jean-Francois Moine wrote:
> On Tue, 01 Sep 2009 14:57:02 +0530
> Sudipto Sarkar <xtremethegreat1@gmail.com> wrote:
>
>   
>> The brightness is more than earlier. 
>> However, this time it only shows a few objects near the light source. 
>> The brightness is still very low, and not as much as is provided by
>> the windoze driver.
>>
>> Can you please tell me, how you figured out which URBs were for the 
>> brightness?
>>     
>
> The brightness is controled by the gamma table. In the driver, the
> exchanges are done in the function put_tab_to_reg(). I have usb snoops
> of the changes made to the values according to the brightness, but also
> to the chroma and contrast. I could not yet find an algorithm to
> generate the values, so, the controls do not work, and the gamma table
> is static.
>
> For your webcam, the values are in the hv7131r_gamma table. Here are
> differents values (17 values in hexadecimal) which I got from usb
> snoops.
>
> 	00 08 19 30 47 5e 74 89 9c ac ba c6 cf d8 df e4 ff
> 	03 0d 1e 37 4e 65 7c 91 a4 b4 c2 ce d8 e0 e7 ed ff
> 	07 12 24 3d 55 6d 84 99 ac bc cb d7 e1 e9 f0 f6 ff
> 	0b 17 2a 44 5c 74 8b a1 b4 c5 d3 df e9 f2 f9 ff ff
> 	10 1c 30 4b 63 7c 93 a9 bc cd dc e8 f2 fb ff ff ff
>
> the next values change the chroma
>
> 	00 07 18 32 4a 63 7c 92 a7 b8 c8 d5 e0 e9 f0 f7 ff
> 	00 03 13 2b 43 5c 74 8b 9f b0 bf cc d7 e0 e8 ee ff
> 	01 0b 1e 38 51 6b 83 9a af c1 d0 dd e8 f2 f9 ff ff
> 	04 0f 23 3d 57 71 8a a1 b6 c8 d8 e5 f0 f9 ff ff ff
> 	00 02 12 2a 42 5b 73 89 9d af be cb d6 df e6 ec ff
>
> and these ones the contrast
>
> 	06 13 29 47 64 80 9c b6 cd e1 f2 ff ff ff ff ff ff
> 	07 14 2a 48 64 80 9c b5 cc df f0 ff ff ff ff ff ff
> 	0b 19 2e 4a 65 80 9a b2 c7 da ea f8 ff ff ff ff ff
> 	10 1d 32 4d 67 80 99 af c3 d5 e4 f1 fb ff ff ff ff
>
>   
I wonder where that appears in the snoop logs.
However, I had written the code to turn on the LED on this camera, back 
when I was trying to write the driver. I figured, it was the same as the 
po1200 HP 2.0 Megapixel one. It works on my camera. I'm attaching an 
edit of the file you gave me earlier today, with the line number 3413 
edited to turn on the LED on, on my camera.