From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.gentoo.org (woodpecker.gentoo.org [140.211.166.183]) (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 F3B4929292A; Tue, 15 Apr 2025 12:28:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=140.211.166.183 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744720095; cv=none; b=RLRNTaqt1ho/PUnvpbwBXxnjqfeGD3JLI/P6KEabGZf8KM9zFIkDbMZyy1LK85IWLQVugw5hEybSjPMYiDwxexhBU3pX6GnZZkjFcnrrjY74T9hzDPvtrgELR4b1Eqdj1WUqJidscq2jtJtDyQ/g/CNXMMvEIdqtHo36uyYp3VI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744720095; c=relaxed/simple; bh=w2RPxSYRBEwwRENpvePKl+T3B+SWPu7DrBRdUIOspv4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=B6x8voBu6Lge2KrITfVWcWaGOCDw/jOTfYdY6gslJXUythf/mJDkCbMYZAJEu2wZAIhzL3RzigQSD64AdQz6PzW0XABfW6bs3MFbbqpHGDVdpOBsXqcuYszwj3HGrJi+pabmuefYyClCcCmfbaws2vUL5tNX1LuLS9+yKk3I7vA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gentoo.org; spf=pass smtp.mailfrom=gentoo.org; arc=none smtp.client-ip=140.211.166.183 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gentoo.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gentoo.org Received: from localhost (unknown [116.232.27.72]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (prime256v1) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: dlan) by smtp.gentoo.org (Postfix) with ESMTPSA id B8113335DE9; Tue, 15 Apr 2025 12:28:11 +0000 (UTC) Date: Tue, 15 Apr 2025 12:28:07 +0000 From: Yixun Lan To: Alex Elder Cc: Guodong Xu , Philipp Zabel , Conor Dooley , ukleinek@kernel.org, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, alex@ghiti.fr, drew@pdp7.com, inochiama@gmail.com, geert+renesas@glider.be, heylenay@4d2.org, tglx@linutronix.de, hal.feng@starfivetech.com, unicorn_wang@outlook.com, duje.mihanovic@skole.hr, linux-pwm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, spacemit@lists.linux.dev Subject: Re: [PATCH 1/9] dt-bindings: pwm: marvell,pxa: add optional property resets Message-ID: <20250415122807-GYA30943@gentoo> References: <20250411131423.3802611-1-guodong@riscstar.com> <20250411131423.3802611-2-guodong@riscstar.com> <20250411-confider-spinster-35f23040d188@spud> <89b6142bacecd4a7742341b88dc1e28c4454527a.camel@pengutronix.de> <20250415101249-GYA30674@gentoo> <0bbd2842-72bc-47a7-832a-fc8833163e32@riscstar.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <0bbd2842-72bc-47a7-832a-fc8833163e32@riscstar.com> Hi Alex, On 07:11 Tue 15 Apr , Alex Elder wrote: > On 4/15/25 5:12 AM, Yixun Lan wrote: > > Hi Philipp, > > > > On 17:54 Tue 15 Apr , Guodong Xu wrote: > >> On Tue, Apr 15, 2025 at 4:53 PM Philipp Zabel wrote: > >>> > >>> On Fr, 2025-04-11 at 17:44 +0100, Conor Dooley wrote: > >>>> On Fri, Apr 11, 2025 at 09:14:15PM +0800, Guodong Xu wrote: > >>>>> Add an optional resets property for the Marvell PWM PXA binding. > >>>>> > >>>>> Signed-off-by: Guodong Xu > >>>>> --- > >>>>> Documentation/devicetree/bindings/pwm/marvell,pxa-pwm.yaml | 3 +++ > >>>>> 1 file changed, 3 insertions(+) > >>>>> > >>>>> diff --git a/Documentation/devicetree/bindings/pwm/marvell,pxa-pwm.yaml b/Documentation/devicetree/bindings/pwm/marvell,pxa-pwm.yaml > >>>>> index 9ee1946dc2e1..9640d4b627c2 100644 > >>>>> --- a/Documentation/devicetree/bindings/pwm/marvell,pxa-pwm.yaml > >>>>> +++ b/Documentation/devicetree/bindings/pwm/marvell,pxa-pwm.yaml > >>>>> @@ -31,6 +31,9 @@ properties: > >>>>> clocks: > >>>>> maxItems: 1 > >>>>> > >>>>> + resets: > >>>>> + maxItems: 1 > >>>> > >>>> Do any of the currently supported devices use a reset? If not, then add > >>>> this in tandem with the new compatible and only allow it there please. > >>> > >>> Also, if spacemit,k1-pwm can not work without the reset being > >>> deasserted, mark it as required. > > > > If I inerpret correctly, only reset requires explicitly being de-asserted, > > need to mark as required? that's being said, if reset comes out as de-asserted > > by default after power reset, then not necessary? > > (in other cases, some device block is in asserted state by default) > > We can often benefit from the state that the boot loader has left > things in, but I think it's better not to assume it if possible. right, I agree mostly > I suppose it might not be required though. > > Anyway, the reset line is available to use; why not require it? > maybe there are cases that users don't want to issue a reset.. so, want to make it optional.. I can think one example that, display controller is up and working from bootloader to linux, reset it will got a flicker picture.. anyway, my question was trying to understand the policy of writting DTS hehind.. > > > thanks > >>> > >> > >> Thank you Philipp. spacemit,k1-pwm can not work without the reset. > >> I will add that in the next version. > >> > >> -Guodong > >> > >>> The driver can still use reset_control_get_optional. > >>> > >>> regards > >>> Philipp > > > -- Yixun Lan (dlan) Gentoo Linux Developer GPG Key ID AABEFD55