Hi,
I tried posting to the linux-usb-devel list, but it seems to have died.
<Extract start>
/*
* Analyse a received field, and fetch the data from it. The field
* content is stored for next report processing (we do differential
* reporting to the layer).
*/
static void hid_input_field(struct hid_device *hid, struct hid_field
*field, __u8 *data, int interrupt, struct pt_regs *regs)
<Extract end>
Why is "differential reporting to the layer" done?
I have a USB device that uses the interrupt urb to notify the PC of
events. Each time an event happens, a usb interrupt is created, and the
driver reads the value from the report. Most of the time the event
contains exactly the same report info as the previous interrupt. As a
result of this differential reporting, I only see the first event, and
then no more until the event changes. How can I get repeated events of
the same report up to user space? I am currently using the
/dev/usb/hiddev0 interface.
Any clues?
For now, I am removing the "differential reporting to the layer" code,
ensuring that all interrupt urbs reach the higher layers.
The "differential reporting" code must be there for a reason, does
anyone know why it is present?
James
On Sat, Aug 05, 2006 at 08:08:34PM +0100, James Courtier-Dutton wrote:
> Hi,
>
> I tried posting to the linux-usb-devel list, but it seems to have died.
No it didn't, I see your post there, and it was answered there too :)
thanks,
greg k-h