Commit 74acc277 authored by Benjamin Tissoires's avatar Benjamin Tissoires Committed by Jiri Kosina
Browse files

HID: core: de-duplicate some code in hid_input_field() 

I had to go twice through the history to get a grasp at this code.
De-duplicate the various tests in one common helper to make it
more explicit.

Note that the `HID_UP_KEYBOARD + 1` condition is tested through
https://gitlab.freedesktop.org/libevdev/hid-tools/-/merge_requests/121



Signed-off-by: default avatarBenjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: default avatarPing Cheng <ping.cheng@wacom.com>
Acked-by: default avatarPeter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: default avatarJiri Kosina <jkosina@suse.cz>
parent 1c1813a7

drivers/hid/hid-core.c

+39 −15
Original line number Diff line number Diff line
@@ -1525,6 +1525,24 @@ static void hid_process_event(struct hid_device *hid, struct hid_field *field, 
		hid->hiddev_hid_event(hid, field, usage, value);

}



/*

 * Checks if the given value is valid within this field

 */

static inline int hid_array_value_is_valid(struct hid_field *field,

					   __s32 value)

{

	__s32 min = field->logical_minimum;



	/*

	 * Value needs to be between logical min and max, and

	 * (value - min) is used as an index in the usage array.

	 * This array is of size field->maxusage

	 */

	return value >= min &&

	       value <= field->logical_maximum &&

	       value - min < field->maxusage;

}



/*

 * Analyse a received field, and fetch the data from it. The field

 * content is stored for next report processing (we do differential
@@ -1539,7 +1557,6 @@ static void hid_input_field(struct hid_device *hid, struct hid_field *field, 
	unsigned offset = field->report_offset;

	unsigned size = field->report_size;

	__s32 min = field->logical_minimum;

	__s32 max = field->logical_maximum;

	__s32 *value;



	value = field->new_value;
@@ -1554,8 +1571,7 @@ static void hid_input_field(struct hid_device *hid, struct hid_field *field, 


		/* Ignore report if ErrorRollOver */

		if (!(field->flags & HID_MAIN_ITEM_VARIABLE) &&

		    value[n] >= min && value[n] <= max &&

		    value[n] - min < field->maxusage &&

		    hid_array_value_is_valid(field, value[n]) &&

		    field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1)

			return;

	}
@@ -1563,21 +1579,29 @@ static void hid_input_field(struct hid_device *hid, struct hid_field *field, 
	for (n = 0; n < count; n++) {



		if (HID_MAIN_ITEM_VARIABLE & field->flags) {

			hid_process_event(hid, field, &field->usage[n], value[n], interrupt);

			hid_process_event(hid,

					  field,

					  &field->usage[n],

					  value[n],

					  interrupt);

			continue;

		}



		if (field->value[n] >= min && field->value[n] <= max

			&& field->value[n] - min < field->maxusage

			&& field->usage[field->value[n] - min].hid

			&& search(value, field->value[n], count))

				hid_process_event(hid, field, &field->usage[field->value[n] - min], 0, interrupt);



		if (value[n] >= min && value[n] <= max

			&& value[n] - min < field->maxusage

			&& field->usage[value[n] - min].hid

			&& search(field->value, value[n], count))

				hid_process_event(hid, field, &field->usage[value[n] - min], 1, interrupt);

		if (hid_array_value_is_valid(field, field->value[n]) &&

		    search(value, field->value[n], count))

			hid_process_event(hid,

					  field,

					  &field->usage[field->value[n] - min],

					  0,

					  interrupt);



		if (hid_array_value_is_valid(field, value[n]) &&

		    search(field->value, value[n], count))

			hid_process_event(hid,

					  field,

					  &field->usage[value[n] - min],

					  1,

					  interrupt);

	}



	memcpy(field->value, value, count * sizeof(__s32));