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 3D7D8221F0C; Thu, 22 May 2025 07:39:09 +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=1747899549; cv=none; b=tpb7Bcwvp9EXBPkULeysmcpU2EhbjyWF8WCR9EHXxUdF0QIKdaB0eRO40L1N2M9RkX2nnbe9hXME0FrgAchfj3eh4Y5hx+kEkW0Mxv7B32Q2xjKf1XvYEOV45DRSCyiJtsWuUI398HP9WF9k31rwsS9K5t5OaugoO2Z85qKvdTQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747899549; c=relaxed/simple; bh=/iaPqy0c+HX2+uonr5lbQ0iX6eNHdizPwfyg0c7fd5k=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=tX0LRhFs2fXBrpcCtOOGYd+WBduCEz7wJ4MP8FQlcOXG16rQ4OrGEnaAadYU8z3boJSqvcZnE+iiPF16Y0c+AkQUWC6M9N4c3AIMbVWnO49u9Jc0Rugi2e0S/eGvbYQvX/iprJ2HSL/TeqkrS6++S+GvfkleQLhi3zuZBo20v1U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZRDfe3mm; 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="ZRDfe3mm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C31B4C4CEE4; Thu, 22 May 2025 07:39:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1747899549; bh=/iaPqy0c+HX2+uonr5lbQ0iX6eNHdizPwfyg0c7fd5k=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ZRDfe3mmSjGc1jix3U1NAucjLjSMdgJCeQrhsoUjojwTIhEc3xtcwgUHVJHyjFOk4 Flc38yuVIo8sUGKJOgQpyen/aQHQGwyp9DpEzROpJxiHZVj8NoFfoNHiafW0Z1G47v 3wNZpEIj5B7cxL+KWpdTne1gu8ukrHpoSicQz10vww+EqT1qg5tnFbS2T5iFd24q5A bKtNz9/oJt83eSV2eqS3alvVX+FapvgpdBDVESlI7mFE/VzhjgxMMeWmPsYdf5y8uv nM4nfFVvu/hPUsSuza2hpety0C/H+Q0w+az7/imJWKZJdPZDBIX/mTyZVjNE5pNhVr Oj7kvMQpmAwsw== Date: Thu, 22 May 2025 08:39:02 +0100 From: Lee Jones To: Ivan Vecera Cc: Andy Shevchenko , netdev@vger.kernel.org, Vadim Fedorenko , Arkadiusz Kubalewski , Jiri Pirko , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Prathosh Satish , "David S. Miller" , Jakub Kicinski , Paolo Abeni , Simon Horman , Michal Schmidt , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org Subject: Re: [PATCH net-next v7 8/8] mfd: zl3073x: Register DPLL sub-device during init Message-ID: <20250522073902.GC8794@google.com> References: <20250507124358.48776-1-ivecera@redhat.com> <20250507124358.48776-9-ivecera@redhat.com> <2e3eb9e3-151d-42ef-9043-998e762d3ba6@redhat.com> <20250507152609.GK3865826@google.com> <20250513094126.GF2936510@google.com> <6f693bb5-da3c-4363-895f-58a267e52a18@redhat.com> Precedence: bulk X-Mailing-List: netdev@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: <6f693bb5-da3c-4363-895f-58a267e52a18@redhat.com> On Tue, 13 May 2025, Ivan Vecera wrote: > On 13. 05. 25 11:41 dop., Lee Jones wrote: > > On Mon, 12 May 2025, Ivan Vecera wrote: > > > > > On 07. 05. 25 5:26 odp., Lee Jones wrote: > > > > On Wed, 07 May 2025, Andy Shevchenko wrote: > > > > > > > > > On Wed, May 07, 2025 at 03:56:37PM +0200, Ivan Vecera wrote: > > > > > > On 07. 05. 25 3:41 odp., Andy Shevchenko wrote: > > > > > > > On Wed, May 7, 2025 at 3:45 PM Ivan Vecera wrote: > > > > > > > > > > ... > > > > > > > > > > > > > +static const struct zl3073x_pdata zl3073x_pdata[ZL3073X_MAX_CHANNELS] = { > > > > > > > > + { .channel = 0, }, > > > > > > > > + { .channel = 1, }, > > > > > > > > + { .channel = 2, }, > > > > > > > > + { .channel = 3, }, > > > > > > > > + { .channel = 4, }, > > > > > > > > +}; > > > > > > > > > > > > > > > +static const struct mfd_cell zl3073x_devs[] = { > > > > > > > > + ZL3073X_CELL("zl3073x-dpll", 0), > > > > > > > > + ZL3073X_CELL("zl3073x-dpll", 1), > > > > > > > > + ZL3073X_CELL("zl3073x-dpll", 2), > > > > > > > > + ZL3073X_CELL("zl3073x-dpll", 3), > > > > > > > > + ZL3073X_CELL("zl3073x-dpll", 4), > > > > > > > > +}; > > > > > > > > > > > > > > > +#define ZL3073X_MAX_CHANNELS 5 > > > > > > > > > > > > > > Btw, wouldn't be better to keep the above lists synchronised like > > > > > > > > > > > > > > 1. Make ZL3073X_CELL() to use indexed variant > > > > > > > > > > > > > > [idx] = ... > > > > > > > > > > > > > > 2. Define the channel numbers > > > > > > > > > > > > > > and use them in both data structures. > > > > > > > > > > > > > > ... > > > > > > > > > > > > WDYM? > > > > > > > > > > > > > OTOH, I'm not sure why we even need this. If this is going to be > > > > > > > sequential, can't we make a core to decide which cell will be given > > > > > > > which id? > > > > > > > > > > > > Just a note that after introduction of PHC sub-driver the array will look > > > > > > like: > > > > > > static const struct mfd_cell zl3073x_devs[] = { > > > > > > ZL3073X_CELL("zl3073x-dpll", 0), // DPLL sub-dev for chan 0 > > > > > > ZL3073X_CELL("zl3073x-phc", 0), // PHC sub-dev for chan 0 > > > > > > ZL3073X_CELL("zl3073x-dpll", 1), // ... > > > > > > ZL3073X_CELL("zl3073x-phc", 1), > > > > > > ZL3073X_CELL("zl3073x-dpll", 2), > > > > > > ZL3073X_CELL("zl3073x-phc", 2), > > > > > > ZL3073X_CELL("zl3073x-dpll", 3), > > > > > > ZL3073X_CELL("zl3073x-phc", 3), > > > > > > ZL3073X_CELL("zl3073x-dpll", 4), > > > > > > ZL3073X_CELL("zl3073x-phc", 4), // PHC sub-dev for chan 4 > > > > > > }; > > > > > > > > > > Ah, this is very important piece. Then I mean only this kind of change > > > > > > > > > > enum { > > > > > // this or whatever meaningful names > > > > > ..._CH_0 0 > > > > > ..._CH_1 1 > > > > > ... > > > > > }; > > > > > > > > > > static const struct zl3073x_pdata zl3073x_pdata[ZL3073X_MAX_CHANNELS] = { > > > > > { .channel = ..._CH_0, }, > > > > > ... > > > > > }; > > > > > > > > > > static const struct mfd_cell zl3073x_devs[] = { > > > > > ZL3073X_CELL("zl3073x-dpll", ..._CH_0), > > > > > ZL3073X_CELL("zl3073x-phc", ..._CH_0), > > > > > ... > > > > > }; > > > > > > > > This is getting hectic. All for a sequential enumeration. Seeing as > > > > there are no other differentiations, why not use IDA in the child > > > > instead? > > > > > > For that, there have to be two IDAs, one for DPLLs and one for PHCs... > > > > Sorry, can you explain a bit more. Why is this a problem? > > > > The IDA API is very simple. > > > > Much better than building your own bespoke MACROs. > > I will try to explain this in more detail... This MFD driver handles > chip family ZL3073x where the x == number of DPLL channels and can > be from <1, 5>. > > The driver creates 'x' DPLL sub-devices during probe and has to pass > channel number that should this sub-device use. Here can be used IDA > in DPLL sub-driver: > e.g. ida_alloc_max(zldev->channels, zldev->max_channels, GFP_KERNEL); > > This way the DPLL sub-device get its own unique channel ID to use. > > The situation is getting more complicated with PHC sub-devices because > the chip can provide UP TO 'x' PHC sub-devices depending on HW > configuration. To handle this the MFD driver has to check this HW config > for particular channel if it is capable to provide PHC functionality. > > E.g. ZL30735 chip has 5 channels, in this case the MFD driver should > create 5 DPLL sub-devices. And then lets say channel 0, 2 and 4 are > PHC capable. Then the MFD driver should create 3 PHC sub-devices and > pass 0, 2 resp. 4 for them. Where is the code that determines which channels are PHC capable? -- Lee Jones [李琼斯]