From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta-231a.oxsus-vadesecure.net (mta-231a.oxsus-vadesecure.net [15.204.3.4]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 086513C13EF for ; Mon, 6 Jul 2026 20:10:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=15.204.3.4 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783368644; cv=none; b=YTd9x6L2M8SOFri3s/C8ixbfOo1UcIoZ2J427DogrZvVj65ewIGKiDPu2IZvmVVtVsbHIL3ZgcWzjrYfzq96hyMywDhCMXt8zErnNxCmYyS6yNpy6tpXva+AdBRKck4LO5ctRDZFFOyGdeL8BqYWqlRlGoQju1zzGVlPfhTcFoA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783368644; c=relaxed/simple; bh=KDBey/dsjSOeLeGET3ERMJhlLAtKM/UFbqKLf1XDo+g=; h=From:To:Subject:Date:Message-ID:MIME-Version:Content-Type; b=nshkXAPZmxf1UnCU0Y1iizFq0xnxjgmh5RsRdrYBVsAMbNoEjxQwBeOxyIipzoWXqdQfHVoGXCHXaYQyY0iuZrjAYkIIN0CYOouX86rsix7jMuEv3G2COBpsH+99pIAtNZVeVHN3iJcNOJnZJKgt7pqjPxilv2HJ3T5k8UhW2jY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=synergy.org; spf=pass smtp.mailfrom=synergy.org; dkim=pass (2048-bit key) header.d=oxsus-vadesecure.net header.i=@oxsus-vadesecure.net header.b=tZN3Ppuy; arc=none smtp.client-ip=15.204.3.4 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=synergy.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=synergy.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=oxsus-vadesecure.net header.i=@oxsus-vadesecure.net header.b="tZN3Ppuy" Authentication-Results: oxsus-vadesecure.net; auth=pass smtp.auth=4@316323 smtp.mailfrom=dave@synergy.org; DKIM-Signature: v=1; a=rsa-sha256; bh=RDQ2qqZUveLezMA6rEGDoDF6Ms4m5EnVg2t1Qu zm1ek=; c=relaxed/relaxed; d=oxsus-vadesecure.net; h=from:reply-to: subject:date:to:cc:resent-date:resent-from:resent-to:resent-cc: in-reply-to:references:list-id:list-help:list-unsubscribe: list-unsubscribe-post:list-subscribe:list-post:list-owner:list-archive; q=dns/txt; s=dkim-202410-rsa2048; t=1783367730; x=1783972530; b=tZN3Ppu y1vzeEljTjW6vfVXMuDX9sEqXZFBfAlCe8//1siHVyRIzKDrIoVhUf14Kud8jgS9iDLELOk IgZ2icTYRoHUvJjuBf5Z/2psm7uH26YqdCI0N4xgnbiLT2OP1C3u/jjT5teCy7HmmnvMiYg Q/PPs0CrV/FUS12/rq43HEBU2IKHApc/rgIE2LzzQF4iYYwCv71rkGbncwMDy45f9v/VTA8 6b/zqJTTTpjiN7I5Vj/FJFks57UGOWRV5KVP/Hi7PrNDuHlmOwO03Kyl9JoE6wcwENaH9gG S0pt1GCNANNdCa1fTgrSDDyTft0iWeuxD8am0wB5O5KedM1OFcg== Received: from proxy-5 ([174.165.77.67]) by oxsus2nmtao01p.internal.vadesecure.com with ngmta id 77051244-18bfcb80323b1835; Mon, 06 Jul 2026 19:55:29 +0000 From: To: Subject: USB Keypad Date: Mon, 6 Jul 2026 12:55:25 -0700 Message-ID: <000401dd0d81$657e4820$307ad860$@synergy.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook 16.0 Thread-Index: Ad0Nf2kloXnkLKc6TuWU91fyvDq83g== Content-Language: en-us Hello, I am working on a mobile device based on Raspberry Pi OS. I am using a USB keypad to navigate the UI of my device. I have purchased 2 models. One has 19 keys and the other has a few more. I've implemented the user-space code to read() the input device. Things are generally working fine. But I have one issue. On both models the keycodes I receive are not unique across all keys. On one, the key labeled INS and the one labeled 0 both send the same code. On the second one, the mapping is even more bizarre. It has duplicated Num Locks and other keys, as well. The number keys are always readable as such, but the other non-number keys can be aliased. My question is simple: is there something I need to do to change the mode of the keypad to send unique codes? Perhaps an ioctl()? I do not know the HID spec. I wonder what pressing the Num Lock key causes an OS (like Windows) or X11 to do to change keypad modes. Is there a document or website I can read that discusses this? Thank you, David