(adding linux-media to the CC)
On Fri, 14 Aug 2009, Stefan Welker wrote:
> Hi there,
>
> Im working with the camera on the A780 Motorola mobile phone which
> uses the pxa_camera module to run micron mt9m111 chip. In the chip
> documentation there is stated that it is possible to run the chip with
> Low-power mode (640 x 512) at 54 Mhz with a framerate of 30 hz. Right
> now the Master clock is Limited by some Lines of code in pxa_camera to
> 26 Mhz which is lcdclk / 4 then a divisor is calculated which is in
> this case 1 .
> Im wondering if it is possible at all to get the 30 hz images (Im
> trying to do real time image processing with this camera , thus the
> latency would benefit a lot from a faster framerate. ) from the chip.
>
> I already tried to set the mclk to 54 Mhz or 52 Mhz which calculates
> the divisor as 0 (dont know if that makes sense)
> but it gets the images at 30 hz then, unfortunately theres something
> wrong as the images get skewed, and also the U/V data somehow gets
> mixed up or something since there are now green stripes in the image.
>
> Do you think there is a hardware limit that prevents the system from
> reading out the camera at 54 Mhz
> (or at least 52 Mhz) which would be lcdclk/2
The comment in the driver in mclk_get_divisor() says
/* mclk <= ciclk / 4 (27.4.2) */
have you had a look at the datasheet section 27.4.2? Please look at it,
then feel free to ask again on the mailing list, if you still have any
questions.
Thanks
Guennadi
---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
