From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from jabberwock.ucw.cz (jabberwock.ucw.cz [46.255.230.98]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7335D1E4A5; Fri, 19 Jan 2024 20:32:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=46.255.230.98 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705696365; cv=none; b=X+fHP4NmzXOpwgZSNY9i2syp1aSuWCT403IpM5lV3fP+Di5wjxkGbqGQxZbCOdvuNKpWcNQ0pdpBKNEIBHo9BokhMVb273Zg8PlvKsRO+24fjtpV3e4WFeDR0DjR9IqN6UyoQQoXpnFEwdgC+CcgfZP027yz9q6TzekWDgchLOI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705696365; c=relaxed/simple; bh=+T57t4scphjXmREAryQ2RC2KLCJQWNQkLcAGX8d3N2Y=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=SMw5I8DqpSFx7FKvKz7yRc1Di0bv1wEAFY/wL7DNFRnjknWtgh8TqQqFWsy5N5ohnqUr8AmQUgJQbChAX/2/1Xua/f7OktN0UMUZosXSQPfpx+YBz/xO3utBR0C54UMDsYtU/YV6qOK1x9SkVnSy2KliP0lMrTOzlDEHXp60tRA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ucw.cz; spf=pass smtp.mailfrom=ucw.cz; dkim=pass (1024-bit key) header.d=ucw.cz header.i=@ucw.cz header.b=NinSCgGW; arc=none smtp.client-ip=46.255.230.98 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ucw.cz Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ucw.cz Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ucw.cz header.i=@ucw.cz header.b="NinSCgGW" Received: by jabberwock.ucw.cz (Postfix, from userid 1017) id 4A3841C0071; Fri, 19 Jan 2024 21:32:40 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ucw.cz; s=gen1; t=1705696360; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=2Z4zR8u3nm1rRi0zh1NzLoJEZgyLkftEGi5YnT+0UVA=; b=NinSCgGWEItpLCFK8x0Plbr7ic7jnW5Xg2ZYjXsM9w+gtEy+UAh0BsWBQQmUsCq0s1Gcrb FOduxoV6A0sLjTsiMplEkepm1nA1DYNxTGdAr5mftTcmZ2Sv1lYCUFw8kVsfLir6lEm9Eq t4D01rdmcjk2BoWgz1riHNWdItpC4+Q= Date: Fri, 19 Jan 2024 21:32:39 +0100 From: Pavel Machek To: Werner Sembach Cc: Hans de Goede , Jani Nikula , jikos@kernel.org, Jelle van der Waa , Miguel Ojeda , Lee Jones , linux-kernel@vger.kernel.org, "dri-devel@lists.freedesktop.org" , linux-input@vger.kernel.org, ojeda@kernel.org, linux-leds@vger.kernel.org Subject: Re: Implement per-key keyboard backlight as auxdisplay? Message-ID: References: <8096a042-83bd-4b9f-b633-79e86995c9b8@redhat.com> <4222268b-ff44-4b7d-bf11-e350594bbe24@redhat.com> <6bbfdd62-e663-4a45-82f4-445069a8d690@redhat.com> <36973f9d-bf67-417d-998c-ce24c38322c3@tuxedocomputers.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="/ZMJYiWSABC/ttn2" Content-Disposition: inline In-Reply-To: <36973f9d-bf67-417d-998c-ce24c38322c3@tuxedocomputers.com> --/ZMJYiWSABC/ttn2 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi! > > > And then storing RGB in separate bytes, so userspace will then > > > always send a buffer of 192 bytes per line (64x3) x 14 rows > > > =3D 3072 bytes. With the kernel driver ignoring parts of > > > the buffer where there are no actual keys. > > That's really really weird interface. If you are doing RGB888 64x14, > > lets make it a ... display? :-). > >=20 > > ioctl always sending 3072 bytes is really a hack. > >=20 > > Small displays exist and are quite common, surely we'd handle this as > > a display: > > https://pajenicko.cz/displeje/graficky-oled-displej-0-66-64x48-i2c-bily= -wemos-d1-mini > > It is 64x48. > >=20 > > And then there's this: > > https://pajenicko.cz/displeje/maticovy-8x8-led-displej-s-radicem-max7219 > > and this: > > https://pajenicko.cz/displeje/maticovy-8x32-led-displej-s-radicem-max72= 19 > >=20 > > One of them is 8x8. > >=20 > > Surely those should be displays, too? >=20 > But what about a light bar with, lets say, 3 zones. Is that a 3x1 display? >=20 > And what about a mouse having lit mousebuttons and a single led light bar= at > the wrist: a 2x2 display, but one is thin but long and one is not used? So indeed LEDs can arranged into various shapes. Like a ring, or this: * * * * * * * https://pajenicko.cz/led-moduly?page=3D2 Dunno. Sounds like a display is still a best match for them. Some of modules are RGB, some are single-color only, I'm sure there will be various bit depths. I guess we can do 3x1 and 2x2 displays. Or we could try to solve keyboards and ignore those for now. Best regards, Pavel --=20 People of Russia, stop Putin before his war on Ukraine escalates. --/ZMJYiWSABC/ttn2 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iF0EABECAB0WIQRPfPO7r0eAhk010v0w5/Bqldv68gUCZarcZwAKCRAw5/Bqldv6 8vorAJ44jwibpMssWa1IOTj5wgRqgYAdpACgsblb5qNdHeBKVZp9qFNQLdR24uQ= =Qwmz -----END PGP SIGNATURE----- --/ZMJYiWSABC/ttn2--