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 487E02620DE; Thu, 8 May 2025 08:38:27 +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=1746693512; cv=none; b=oyZaHNws0FeSRhSncKXvy98pvp6C81qhBmBBnrj3mJuv/in0e1uCrAD+voYHgkCHMz/qCq/T51iUUQKwE61SIX4e6I+DmNg8PF9kuDCKyDKmhn3oXpW6pGbq4naqQIH0cioLlMApJF+iioIlJW5Acdhcxw47IHCu6937fMCtDSk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746693512; c=relaxed/simple; bh=k2Zp0OCJhicYzRUQR/Kgk6rk1liK2EZ01nmsvcrs+gw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=tW257IWPZRhxcxBoQtjIwXrFu9JmFLM5262uSXpAQUr1pr0h+KVPZMTUw6IzyCu3yhQzcVVTsig5C/bjAouG6h2vcEgq79GheYtVW4fbVAzxCDkku4ll54rld2MXL1dKLQ/QXhTnOEyJ+FpWI2X+SKOsfePuU237XlGFPgW6e9c= 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=PrNROnZx; 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="PrNROnZx" Received: by jabberwock.ucw.cz (Postfix, from userid 1017) id 119011C00AB; Thu, 8 May 2025 10:38:26 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ucw.cz; s=gen1; t=1746693506; 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=ckLCaz9JTwf1JWFkvqfAI949tTAoo5JbgEelAt8RQvk=; b=PrNROnZxCeea0Jho3SCM2w2/XQ838ikowGDgqD5QtqDpcbs2e38VTtLBxxZMMMgBH106hN ElEgO86ZtWA95vGDx4pxSfOv1o9I+6k7QtMEG7l7O3C1NTem1cc1t5S4b7wJXNH5bXaSdM eWoeYLiJhf2uUsYUbdE6G4bbk2b6sMs= Date: Thu, 8 May 2025 10:38:25 +0200 From: Pavel Machek To: Nam Tran Cc: andy@kernel.org, geert@linux-m68k.org, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, christophe.jaillet@wanadoo.fr, corbet@lwn.net, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, florian.fainelli@broadcom.com, bcm-kernel-feedback-list@broadcom.com, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v8 0/5] auxdisplay: add support for TI LP5812 4x3 Matrix LED driver Message-ID: References: <20250429170220.8145-1-trannamatk@gmail.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="DXdxuze0uvDm4WRw" Content-Disposition: inline In-Reply-To: <20250429170220.8145-1-trannamatk@gmail.com> --DXdxuze0uvDm4WRw Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi! > > > Thank you, Pavel, for the confirmation. > > > Thank you, Geert, for the review and the question. > > >=20 > > > I would like to make it clearer. > > >=20 > > > On Mon, 28 Apr 2025 Geert Uytterhoeven wrote: > > >=20 > >=20 > > > > > > > - Move driver to drivers/auxdisplay/ instead of drivers/leds/. > > > > > > > - Rename files from leds-lp5812.c/.h to lp5812.c/.h. > > > > > > > - Move ti,lp5812.yaml binding to auxdisplay/ directory, > > > > > > > and update the title and $id to match new path. > > > > > > > - No functional changes to the binding itself (keep Reviewed-= by). > > > > > > > - Update commit messages and patch titles to reflect the move. > > > > > > > - Link to v7: https://lore.kernel.org/linux-leds/202504221901= 21.46839-1-trannamatk@gmail.com/ > > > > > > > > > > > > Out of sudden without discussing with auxdisplay maintainers/re= viewers? > > > > > > Thanks, no. > > > > > > Please, put into the cover letter the meaningful summary of wha= t's > > > > > > going on and why this becomes an auxdisplay issue. Brief review= of the > > > > > > bindings sounds more likely like LEDS or PWM subsystems. > > > > > > > > > > It is 4x3 matrix. That means it is not suitable for LEDs. I don't > > > > > believe it is suitable for PWM, either -- yes, it is 36 PWM outpu= ts, > > > > > but... > > > >=20 > > > > Is it intended to be used as a 4x3 matrix, or is this just an inter= nal > > > > wiring detail, and should it be exposed as 12 individual LEDs inste= ad? > > >=20 > > > The 4=C3=973 matrix is a real and fundamental aspect of the LP5812=E2= =80=99s operation. > > > It is not just an internal wiring detail. > > > The device adopts a Time-Cross-Multiplexing (TCM) structure, where 4 = output > > > pins control 12 LED dots individually through scanning. Each pin incl= udes > > > both high-side and low-side drive circuits, meaning matrix multiplexi= ng is > > > required for proper operation =E2=80=94 it cannot be treated as 12 co= mpletely > > > independent LEDs. > >=20 > > Scanning is really a detail. > >=20 > > If this is used as rectangular 4x3 display, then it goes to auxdisplay. > >=20 > > If this is used as a power LED, SD activity LED, capslock and numlock > > ... placed randomly all around the device, then it goes LED subsystem. >=20 > The LP5812 is used for LED status indication in devices like smart speake= rs, > wearables, and routers, not as a structured rectangular display. Show us one device where it is used, photo would be best. I suspect that the router use might indeed qualify for LED subsystem. You described is at 4x3 display, but it is really used as 4xRGB? > Given that, it seems to match the LED subsystem better than auxdisplay, d= oesn't it? Seems so, yes. From description, I assumed it was 4x3xRGB, not 4xRGB. Best regards, Pavel --=20 I don't work for Nazis and criminals, and neither should you. Boycott Putin, Trump, and Musk! --DXdxuze0uvDm4WRw Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iF0EABECAB0WIQRPfPO7r0eAhk010v0w5/Bqldv68gUCaBxtgQAKCRAw5/Bqldv6 8mN6AJwN7zf8tTTp+bxWAqTTF1AoTBaggQCbBSUYvVJF5PV+ahfMfUjtZcxAwkw= =EZPf -----END PGP SIGNATURE----- --DXdxuze0uvDm4WRw--