From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 C3EDE27002F; Thu, 27 Feb 2025 15:52:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740671559; cv=none; b=uy8CREpKoeWdfKIpwwoBLeGY0t0SDLPZlvKb8P1Cj9KIDDn1vBuUBFA7NEcBKKJXsMSTVXOFb1nX213iXNcnfyJbeSRxo9qPJqc0Y7QkHH52iQsM5i2GPNHa0DjdrLmw+eT9RWrCZ+SgH3LVpXMlANoCIL09m56pCUtOm9dBvyA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740671559; c=relaxed/simple; bh=JOi6jvqrpwn0mQdkcXsd75YE/yZBfD5lrwfCPQknSIs=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pyPbLa8Agp3ZaDIDY9uxmw95EW2XncE4Ian3HEz56mx1x51rg81c/0tA5bpQgYeRGEULwNsvMaQlSdEpxf7ewkri44yI9okf070EhgJUg19hGR5hUWaBKintFhtiSUrhTexaL1HC8nnATEIv+LHh3B/LkOAP65kI+E8A2eiOhVE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=qIh54mAX; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="qIh54mAX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D9093C4CEDD; Thu, 27 Feb 2025 15:52:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1740671559; bh=JOi6jvqrpwn0mQdkcXsd75YE/yZBfD5lrwfCPQknSIs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=qIh54mAXCIHTzFega3kPEvDfLgCHCw3Zw+f/GacvtJTPUu/pIcXY19EEsSUFoE+Pj yYQ+VsqjX0bp/iYcNhT8sAu5BgahFtR+TsUSyGhk4xg3n9On4lYgJjo32ZCaJLyxHg BBFAaJJr+LNWsHOoTCney7KYvpTgbyZQBw/8IGDkGXrCyyEPBynIg5RGMGsnAjsLFy IuULk6gLAdR97RR0ol+CDZrU+NUqEHNAxrDjQXYaqUdSCh2fXCuFt2kaaoPJSRsQWG JjQ16ZbcXxTYRPGGOoplSDX8XgP6aIE7dZzcTHW0u1a9QMtQV/UayWHmzranKpCFkv F34pwqARH64+w== Date: Fri, 28 Feb 2025 00:52:34 +0900 From: William Breathitt Gray To: Alexandre Belloni , Kamel Bouhara Cc: =?iso-8859-1?B?Q3Pza+Fz?= Bence , linux-arm-kernel@lists.infradead.org, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, Dharma.B@microchip.com, Ludovic Desroches , Nicolas Ferre , Jonathan Cameron , Thomas Petazzoni Subject: Re: [PATCH v4 0/2] microchip-tcb-capture: Add Capture, Compare, Overflow etc. events Message-ID: References: <20250211151914.313585-3-csokas.bence@prolan.hu> <8fb9f188-3065-4fdc-a9f1-152cc5959186@prolan.hu> <20250227135330.GC182392@tpx1.home> <202502271437280a6701d8@mail.local> 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-sha512; protocol="application/pgp-signature"; boundary="9gI8yjbOsFJ0jwEr" Content-Disposition: inline In-Reply-To: --9gI8yjbOsFJ0jwEr Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Feb 28, 2025 at 12:13:00AM +0900, William Breathitt Gray wrote: > On Thu, Feb 27, 2025 at 03:37:28PM +0100, Alexandre Belloni wrote: > > On 27/02/2025 23:22:36+0900, William Breathitt Gray wrote: > > > Skimming through the driver, it looks like what we'll need is for > > > mchp_tc_counts[] to have all three TCCs defined, then have > > > mchp_tc_probe() match on a TCB node and configure each TCC. Once that= 's > > > setup, then whenever we need to identify which TCC a callback is > > > exposing, we can get it from count->id. > > >=20 > > > So for example, the TC_CV register offset is calculated as 0x00 + > > > channel * 0x40 + 0x10. In the count_read() callback we can leverage > > > count->id to identify the TCC and thus get the respective TC_CV regis= ter > > > at offset + count->id * 0x40 + 0x10. > > >=20 > >=20 > > We can't do that because the TCC of a single TCB can have a mix of > > different features. I struggled with the breakage to move away from the > > one TCB, one feature state we had. > > Be fore this, it was not possible to mix features on a single TCB, now, > > we can have e.g. the clocksource on TCC 0 and 1 of TCB0 and a PWM on > > TCC 2. mchp_tc_probe must not match on a TCB node... >=20 > Okay I see what you mean, if we match on a TCB mode then we wouldn't be > able to define the cases where one TCC is different from the next in the > same TCB. >=20 > The goal however isn't to support all functionality (i.e. PWM-related > settings, etc.) in the counter driver, but just expose the TCB > configuration options that affect the TCCs when configured for counter > mode. For example, the sysfs attributes can be created, but they don't > have to be available until the TCC is in the appropriate mode (e.g. > return -EBUSY until they are in a counter mode). >=20 > Is there a way to achieve that? Maybe there's a way we can populate the > sysfs tree on the first encountered TCC, and then somehow indicate when > additional TCCs match. Attributes can become available then dynamically > based on the TCCs that match. >=20 > William Breathitt Gray Sorry, let me step back for a moment because maybe I'm trying to solve a problem that might not actually be a problem. I see functionality settings available in the TC Block Mode Register (BMR) that can affect multiple TCCs at a time. Are these BMR settings exposed already to users in someway? If not, do we have a way to introduce these settings if someone wants them; e.g. would the AutoCorrection function enable bit be exposed as a sysfs attribute, or configured in the devicetree? Finally, if there's not much interest in general for exposing these BMR settings, then I suppose there is no need to change how things are right now with the microchip-tcb-capture module and we can just keep it the way it is. That's my only concern, whether there are users that want to control these settings but don't have a way right now. William Breathitt Gray --9gI8yjbOsFJ0jwEr Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEARYKAB0WIQSNN83d4NIlKPjon7a1SFbKvhIjKwUCZ8CKQgAKCRC1SFbKvhIj K++9AP9+Rmsilcgybpn7JO4p7Ml4k8jgN+zhXDy4QnHC1QH+DwD/avZEHG+vxsDd UgB4AwcPFcN8MHVAEbkl10k8O9MmcAk= =GOuM -----END PGP SIGNATURE----- --9gI8yjbOsFJ0jwEr--