Re: gspca_pac7302: sporatdic problem when plugging the device

[Jean-Francois Moine <moinejf@free.fr>]

On Sun, 10 Jan 2010 17:58:58 +0100
Németh Márton <nm127@freemail.hu> wrote:

> Then I plugged and unplugged the device 16 times. When I last plugged
> the device I get the following error in the dmesg:
> 
> [32393.421313] gspca: probing 093a:2626
> [32393.426193] gspca: video0 created
> [32393.426958] gspca: probing 093a:2626
> [32393.426968] gspca: Interface class 1 not handled here
> [32394.005917] pac7302: reg_w_page(): Failed to write register to
> index 0x49, value 0x0, error -71
> [32394.067799] gspca: set alt 8 err -71
> [32394.090792] gspca: set alt 8 err -71
> [32394.118159] gspca: set alt 8 err -71
> 
> The 17th plug was working correctly again. I executed this test on an
> EeePC 901.
> 
> This driver version contains the msleep(4) in the reg_w_buf().
> However, here the reg_w_page() fails, which does not have msleep()
> inside. I don't know what is the real problem, but I am afraid that
> slowing down reg_w_page() would make the time longer when the device
> can be used starting from the event when it is plugged.

Hi again,

I don't understand what you mean by:
> This driver version contains the msleep(4) in the reg_w_buf().
> However, here the reg_w_page() fails, which does not have msleep()
> inside.

Indeed the delay will slow down the webcam start (256 * 4 ms = 1s).

If having a delay fixes the problem, then, as the error always occurs
at the same index 0x49 (3 reports), a single delay could be set before
writing to this index. Do you want I code this for test?

Regards.

-- 
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Jef		|		http://moinejf.free.fr/