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 BC5F81CAAC; Tue, 16 Jan 2024 17:34:18 +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=1705426458; cv=none; b=JwfG+wCP4ymxZmOssoO51ZNA0BqmvTNo2Iz0Sa6R9izn+i5KFl/qwgiLNZmOOabQdX7gYoPAMJYzCLs49CUlPnBnAFyHbHkEmQm28AZ7LXNtBS8gDsMxUotT1J/hN6E1HXS96UC1ZmE07FjFYuiqMtbgm7alXQydFjj4WH37WOY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705426458; c=relaxed/simple; bh=8p3Bv9fS9hcvnux4i7+QsuaRONJtDzRbjULEc/qM+pk=; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition: In-Reply-To; b=Hv7ZqiVKy7R+zXCMH1UJjpR2ZA389lU7zMCXDw9NHzwrl74V71q/Sr/lj7A3C2kqbs1J4+oVsmB7/1zI8emhMyGHQ4KqPquCbI0ZyXMgu7g9CZAVAQKggPsmeA/ojTVTrfakUu0t026osxhzquRWdDAzUGZGlMbKTht/un3ww2U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=suoP77rj; 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="suoP77rj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E79ABC433C7; Tue, 16 Jan 2024 17:34:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1705426458; bh=8p3Bv9fS9hcvnux4i7+QsuaRONJtDzRbjULEc/qM+pk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=suoP77rjxNLBOyGKknnGu7OlFdoZTknBpSYJt471v4NArHDJPfOnHKszO3PmsVQkG fkF5NwYMP7b3BBAKAPpHbeGN8tpU/rHmElwy5k9c8vJEdTq3fZTPtfalX+XRvRBf9Z 040bLDMI46bsENQZdwUSkZLXG24eZAe74Gw6GJkF8RaFmsFsBqtK0sAdnwdi5GfN1b LCT2a1wTRXOFLfhaanRAqXqVFlSWfYvStB4ZWGqheR79z5M4JVxtCrQMzO82N6HVtb Nxstn9oDb3ARbT03AyplV0x+hONRyV2qtJUgFhBEa30RwXgyrRe5Py/k9bEcFZR9oF C1gQPtza/RNNQ== Date: Tue, 16 Jan 2024 17:34:13 +0000 From: Conor Dooley To: Laurent Pinchart Cc: Geert Uytterhoeven , Daniel Lezcano , Thomas Gleixner , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Yoshinori Sato , devicetree@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-sh@vger.kernel.org Subject: Re: [PATCH] dt-bindings: timer: renesas,tmu: Document input capture interrupt Message-ID: <20240116-coasting-pastrami-1dda8d1025d0@spud> References: <20240115-wages-secluded-b44f4eb13323@spud> <20240115170807.GJ5869@pendragon.ideasonboard.com> Precedence: bulk X-Mailing-List: linux-sh@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="PLgkBpzBz5n2FhT/" Content-Disposition: inline In-Reply-To: <20240115170807.GJ5869@pendragon.ideasonboard.com> --PLgkBpzBz5n2FhT/ Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jan 15, 2024 at 07:08:07PM +0200, Laurent Pinchart wrote: > On Mon, Jan 15, 2024 at 05:48:18PM +0100, Geert Uytterhoeven wrote: > > Hi Conor, > >=20 > > On Mon, Jan 15, 2024 at 5:13=E2=80=AFPM Conor Dooley = wrote: > > > On Mon, Jan 15, 2024 at 02:45:39PM +0100, Geert Uytterhoeven wrote: > > > > Some Timer Unit (TMU) instances with 3 channels support a fourth > > > > interrupt: an input capture interrupt for the third channel. > > > > > > > > While at it, document the meaning of the four interrupts, and add > > > > "interrupt-names" for clarity. > > > > > > > > Update the example to match reality. > > > > > > > > Inspired by a patch by Yoshinori Sato for SH. > > > > > > > > Signed-off-by: Geert Uytterhoeven > >=20 > > > > --- a/Documentation/devicetree/bindings/timer/renesas,tmu.yaml > > > > +++ b/Documentation/devicetree/bindings/timer/renesas,tmu.yaml > > > > @@ -46,7 +46,19 @@ properties: > > > > > > > > interrupts: > > > > minItems: 2 > > > > - maxItems: 3 > > > > + items: > > > > + - description: Underflow interrupt 0 > > > > + - description: Underflow interrupt 1 > > > > + - description: Underflow interrupt 2 > > > > + - description: Input capture interrupt 2 > > > > > > Seeing "input capture interrupt 2" makes me wonder, are there two (or > > > more!) other input capture interrupts that are still out there, > > > undocumented, and looking for a home? >=20 > Maybe writing this as >=20 > - description: Underflow interrupt, channel 0 > - description: Underflow interrupt, channel 1 > - description: Underflow interrupt, channel 2 > - description: Input capture interrupt, channel 2 I, for one, prefer this wording. > would make it clearer ? >=20 > I'm also wondering if we really need to add interrupt-names. Drivers > can't depend on the names due to backward compatibility, what benefit > does it bring to add them to the bindings ? Adding a -names property and not making it required has always seemed like a waste of time to me. Granted, making it required post-factum has other problems, so I am inclined to agree that it adds nothing. >=20 > > SoCs can have multiple TMU instances. > > Each TMU instance has 2 or 3 timer channels. > > Each timer channel has an underflow interrupt. > > Only the third channel may have an optional input capture interrupt > > (which is not supported yet by the Linux driver). > > Hence each instance can have 2, 3, or 4 interrupts. > >=20 > > See "RZ/G Series, 2nd Generation User's Manual: Hardware"[1], > > Section 69 ("Timer Unit (TMU)": > > - Figure 69.2: Block Diagram of TMU, > > - Section 69: Interrupt > >=20 > > Note that the documentation uses a monotonic increasing numbering > > of the channels, across all instances. > >=20 > > [1] https://www.renesas.com/us/en/products/microcontrollers-microproces= sors/rz-mpus/rzg2h-ultra-high-performance-microprocessors-quad-core-arm-cor= tex-a57-and-quad-core-arm-cortex-a53-cpus-3d >=20 > --=20 > Regards, >=20 > Laurent Pinchart >=20 --PLgkBpzBz5n2FhT/ Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCZaa+FQAKCRB4tDGHoIJi 0hJKAPsH2IaDOPlurMPkBUuO019dDgDcIkdyy3NJnFmex6flPAEA3v8Ly8XOMz9L LAWEsu4AzTmlAFdnbKbgDQzeugjdYQo= =F/w/ -----END PGP SIGNATURE----- --PLgkBpzBz5n2FhT/--