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. -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html