Hi Mauro,
>
> em28xx is a good reference.
>
I'm looking at it.
In fact, I have a first question: why there is a limit to the number of devices
the driver support? I found the same idea in easycap original
implementation, but I
can't understand why do we have to limit in such a way.
/* Check to see next free device and mark as used */
do {
nr = find_first_zero_bit(&em28xx_devused, EM28XX_MAXBOARDS);
if (nr >= EM28XX_MAXBOARDS) {
/* No free device slots */
printk(DRIVER_NAME ": Supports only %i em28xx
boards.\n",
EM28XX_MAXBOARDS);
retval = -ENOMEM;
goto err_no_slot;
}
} while (test_and_set_bit(nr, &em28xx_devused));
>
> It is not clear, from the easycap code, where the I2C address
> is stored:
>
> int write_saa(struct usb_device *p, u16 reg0, u16 set0)
> {
> if (!p)
> return -ENODEV;
> SET(p, 0x200, 0x00);
> SET(p, 0x204, reg0);
> SET(p, 0x205, set0);
> SET(p, 0x200, 0x01);
> return wait_i2c(p);
> }
I think i2c_address it is near registers 0x200/0x204, which gets
initialised at setup_stk().
I'll have a closer look.
Thanks for your comments,
Ezequiel.
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