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 E83EA2528E1; Tue, 15 Apr 2025 23:06:54 +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=1744758416; cv=none; b=gtq2Eov1Ca96OvX4OTJBz5GPB555NVT7zGTTrkBD7N+ytJTAH0AmWNhRcbFRPplJmvad2nZOfKdjCrV5pk7+SrR0dHjYzl9cjuMIQXcYqDqvZ6GQ48stv62gsD/Vrp3XwkKZPH8pxgI5RRhkyxVByLJsYDAJGu22AolemEWLS6k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744758416; c=relaxed/simple; bh=Q3Ya5E9jgZNJaOvVG2ieIXqSWyLeJz1NnSZgYxNKszA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Ki2QQTGOtcDDhRJB1hfU2Vaq9BoqHDMgYBNdYIjXmUw4E3EOa0cJ0mDpjuejMFr+0d3KZ4ThlanBTGVOjpQvCeIQcW/7wHJdYlDKPxfKd0C2eMS9VNQXhnoEAYc3HIBM0WzHUNCN6kdj0TrF5tL1al22vCyIpy/YPMfoZTYTlao= 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 B2696343026; Tue, 15 Apr 2025 23:06:53 +0000 (UTC) Date: Tue, 15 Apr 2025 23:06:49 +0000 From: Yixun Lan To: Rob Herring Cc: Linus Walleij , Krzysztof Kozlowski , Conor Dooley , linux-gpio@vger.kernel.org, devicetree@vger.kernel.org, linux-riscv@lists.infradead.org, spacemit@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] pinctrl: spacemit: add clock support for K1 SoC Message-ID: <20250415230649-GYB30943@gentoo> References: <20250412-02-k1-pinctrl-clk-v1-0-e39734419a2d@gentoo.org> <20250412-02-k1-pinctrl-clk-v1-2-e39734419a2d@gentoo.org> <20250412182737.GA1425287-robh@kernel.org> <20250412223431-GYA25375@gentoo> <20250415193851.GA846160-robh@kernel.org> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250415193851.GA846160-robh@kernel.org> Hi Rob, On 14:38 Tue 15 Apr , Rob Herring wrote: > On Sat, Apr 12, 2025 at 10:34:31PM +0000, Yixun Lan wrote: > > Hi Rob, > > > > On 13:27 Sat 12 Apr , Rob Herring wrote: > > > On Sat, Apr 12, 2025 at 02:58:11PM +0800, Yixun Lan wrote: > > > > For SpacemiT K1 SoC's pinctrl, explicitly acquiring clocks in > > > > the driver instead of relying on bootloader or default hardware > > > > settings to enable it. > > > > > > > > Signed-off-by: Yixun Lan > > > > --- > > > > drivers/pinctrl/spacemit/pinctrl-k1.c | 10 ++++++++++ > > > > 1 file changed, 10 insertions(+) > > > > > > > > diff --git a/drivers/pinctrl/spacemit/pinctrl-k1.c b/drivers/pinctrl/spacemit/pinctrl-k1.c > > > > index 67e867b04a02ea1887d93aedfdea5bda037f88b1..3805fb09c1bc3b8cf2ccfc22dd25367292b397b9 100644 > > > > --- a/drivers/pinctrl/spacemit/pinctrl-k1.c > > > > +++ b/drivers/pinctrl/spacemit/pinctrl-k1.c > > > > @@ -2,6 +2,7 @@ > > > > /* Copyright (c) 2024 Yixun Lan */ > > > > > > > > #include > > > > +#include > > > > #include > > > > #include > > > > #include > > > > @@ -721,6 +722,7 @@ static int spacemit_pinctrl_probe(struct platform_device *pdev) > > > > { > > > > struct device *dev = &pdev->dev; > > > > struct spacemit_pinctrl *pctrl; > > > > + struct clk *func_clk, *bus_clk; > > > > const struct spacemit_pinctrl_data *pctrl_data; > > > > int ret; > > > > > > > > @@ -739,6 +741,14 @@ static int spacemit_pinctrl_probe(struct platform_device *pdev) > > > > if (IS_ERR(pctrl->regs)) > > > > return PTR_ERR(pctrl->regs); > > > > > > > > + func_clk = devm_clk_get_optional_enabled(dev, "func"); > > > > + if (IS_ERR(func_clk)) > > > > + return dev_err_probe(dev, PTR_ERR(func_clk), "failed to get func clock\n"); > > > > + > > > > + bus_clk = devm_clk_get_optional_enabled(dev, "bus"); > > > > + if (IS_ERR(bus_clk)) > > > > + return dev_err_probe(dev, PTR_ERR(bus_clk), "failed to get bus clock\n"); > > > > > > Do you really need these to be optional? Yes, it maintains > > > > > Yes, the motivation here to make it optional is maintaining the > > compatibility, to not break the case of using old dtb with new kernel, > > since the serial console device (uart0) is activated now [1] > > > > IIUC, from the DT perspective, it's mandatory to keep this compatibility? > > It's up to the platform. It's only mandatory to understand you are > breaking compatibility when you do. > > > > > In dt-binding of patch [1/2], the clocks/clock-names has been described as > > required property, so it's sort of mandatory from DT's view. > > > > One lesson I learned is that the pinctrl dt node shouldn't be activated > > untill all prerequisite dependencies meet.. it's ok to push the driver, > > but should postpone the DT part.. > > > > > compatibility, but if this platform isn't stable, then do you really > > > need that? > > > > > I don't get what's your meaning of "isn't stable" here, the fact won't > > change for K1 SoC: the pinctrl controller requires two clocks > > You required 1 clock and now you require 2. That's not stable. previously pinctrl requires no clock (no clock property populated) > Generally, early on with platforms, their DT is not complete enough to > maintain compatibility. There's also likely not many users or h/w > availability for compatibility to be an issue. So requiring the DT to be > in-sync with the kernel is not a problem. > Ok, then in this case, I will simply drop this _optional_ API thanks -- Yixun Lan (dlan) Gentoo Linux Developer GPG Key ID AABEFD55