Commit aa9b760c authored Nov 04, 2018 by Linus Walleij Committed by Jiri Kosina Nov 06, 2018

HID: fix up .raw_event() documentation



The documentation for the .raw_event() callback says that if the
driver return 1, there will be no further processing of the event,
but this is not true, the actual code in hid-core.c looks like this:

  if (hdrv && hdrv->raw_event && hid_match_report(hid, report)) {
           ret = hdrv->raw_event(hid, report, data, size);
           if (ret < 0)
                   goto unlock;
   }

   ret = hid_report_raw_event(hid, type, data, size, interrupt);

The only return value that has any effect on the processing is
a negative error.

Correct this as it seems to confuse people: I found bogus code in
the Razer out-of-tree driver attempting to return 1 here.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

parent 3fc202e8

include/linux/hid.h

+2 −2

Original line number	Original line	Diff line number	Diff line
	@@ -722,8 +722,8 @@ struct hid_usage_id {
	* input will not be passed to raw_event unless hid_device_io_start is		* input will not be passed to raw_event unless hid_device_io_start is
	* called.		* called.
	*		*
	* raw_event and event should return 0 on no action performed, 1 when no		* raw_event and event should return negative on error, any other value will
	* further processing should be done and negative on error		* pass the event on to .event() typically return 0 for success.
	*		*
	* input_mapping shall return a negative value to completely ignore this usage		* input_mapping shall return a negative value to completely ignore this usage
	* (e.g. doubled or invalid usage), zero to continue with parsing of this		* (e.g. doubled or invalid usage), zero to continue with parsing of this

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