From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 369C0C433F5 for ; Thu, 7 Oct 2021 10:41:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 121FD6135E for ; Thu, 7 Oct 2021 10:41:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240943AbhJGKn1 (ORCPT ); Thu, 7 Oct 2021 06:43:27 -0400 Received: from so254-9.mailgun.net ([198.61.254.9]:15062 "EHLO so254-9.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241088AbhJGKnY (ORCPT ); Thu, 7 Oct 2021 06:43:24 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1633603290; h=Content-Transfer-Encoding: Content-Type: MIME-Version: Message-ID: In-Reply-To: Date: References: Subject: Cc: To: From: Sender; bh=FZv7up9pezh0ULf63JB/fz3Zol9bcHG9+0bdesm9Xmw=; b=utyb0q4heUQHjM2xN4LBCviAs239efIyXmbwlc52JhK8grYJ8zjtpaUEhUl5wVgYZWQe055F Kp5XzUmeSGMsv4hfTZj/u1mT3ZLMGrVeu9JLOILnQuKw+KTQUH/xLWZCda4asNGNW1E3h2Y8 mbe9wNbqoUyXdWJMOMZOGd9Ui3o= X-Mailgun-Sending-Ip: 198.61.254.9 X-Mailgun-Sid: WyI3YTAwOSIsICJsaW51eC13aXJlbGVzc0B2Z2VyLmtlcm5lbC5vcmciLCAiYmU5ZTRhIl0= Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n05.prod.us-west-2.postgun.com with SMTP id 615eced603355859c85c5816 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Thu, 07 Oct 2021 10:41:26 GMT Sender: kvalo=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 3896BC43617; Thu, 7 Oct 2021 10:41:26 +0000 (UTC) Received: from tykki (tynnyri.adurom.net [51.15.11.48]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: kvalo) by smtp.codeaurora.org (Postfix) with ESMTPSA id 0DED9C4338F; Thu, 7 Oct 2021 10:41:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 smtp.codeaurora.org 0DED9C4338F Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=codeaurora.org From: Kalle Valo To: =?utf-8?B?SsOpcsO0bWU=?= Pouiller Cc: linux-wireless@vger.kernel.org, netdev@vger.kernel.org, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, Greg Kroah-Hartman , "David S . Miller" , devicetree@vger.kernel.org, Rob Herring , linux-mmc@vger.kernel.org, Pali =?utf-8?Q?Roh?= =?utf-8?Q?=C3=A1r?= , Ulf Hansson Subject: Re: [PATCH v7 05/24] wfx: add main.c/main.h References: <20210920161136.2398632-1-Jerome.Pouiller@silabs.com> <3570035.Z1gqkuQO5x@pc-42> <875yu9cjvk.fsf@codeaurora.org> <2672405.M38RcEoSet@pc-42> Date: Thu, 07 Oct 2021 13:41:18 +0300 In-Reply-To: <2672405.M38RcEoSet@pc-42> (=?utf-8?B?IkrDqXLDtG1l?= Pouiller"'s message of "Thu, 07 Oct 2021 12:00:18 +0200") Message-ID: <87zgrl86cx.fsf@codeaurora.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org J=C3=A9r=C3=B4me Pouiller writes: >> >> >> I'm not really fond of having this kind of ASCII based parser in t= he >> >> >> kernel. Do you have an example compressed file somewhere? >> >> > >> >> > An example of uncompressed configuration file can be found here[1].= Once >> >> > compressed with [2], you get: >> >> > >> >> > {a:{a:4,b:1},b:{a:{a:4,b:0,c:0,d:0,e:A},b:{a:4,b:0,c:0,d:0,e:B}= ,c:{a:4,b:0,c:0,d:0,e:C},d:{a:4,b:0,c:0,d:0,e:D},e:{a:4,b:0,c:0,d:0,e:E},f:= {a:4,b:0,c:0,d:0,e:F},g:{a:4,b:0,c:0,d:0,e:G},h:{a:4,b:0,c:0,d:0,e:H},i:{a:= 4,b:0,c:0,d:0,e:I},j:{a:4,b:0,c:0,d:0,e:J},k:{a:4,b:0,c:0,d:0,e:K},l:{a:4,b= :0,c:0,d:1,e:L},m:{a:4,b:0,c:0,d:1,e:M}},c:{a:{a:4},b:{a:6},c:{a:6,c:0},d:{= a:6},e:{a:6},f:{a:6}},e:{b:0,c:1},h:{e:0,a:50,b:0,d:0,c:[{a:1,b:[0,0,0,0,0,= 0]},{a:2,b:[0,0,0,0,0,0]},{a:[3,9],b:[0,0,0,0,0,0]},{a:A,b:[0,0,0,0,0,0]},{= a:B,b:[0,0,0,0,0,0]},{a:[C,D],b:[0,0,0,0,0,0]},{a:E,b:[0,0,0,0,0,0]}]},j:{a= :0,b:0}} >> >> >> >> So what's the grand idea with this braces format? I'm not getting it. >> > >> > - It allows to describe a tree structure >> > - It is ascii (easy to dump, easy to copy-paste) >> > - It is small (as I explain below, size matters) >> > - Since it is similar to JSON, the structure is obvious to many peop= le >> > >> > Anyway, I am not the author of that and I have to deal with it. >>=20 >> I'm a supported for JSON like formats, flexibility and all that. But >> they belong to user space, not kernel. >>=20 >> >> Usually the drivers just consider this kind of firmware configuration >> >> data as a binary blob and dump it to the firmware, without knowing wh= at >> >> the data contains. Can't you do the same? >> > >> > [I didn't had received this mail :( ] >> > >> > The idea was also to send it as a binary blob. However, the firmware u= se >> > a limited buffer (1500 bytes) to parse it. In most of case the PDS exc= eeds >> > this size. So, we have to split the PDS before to send it. >> > >> > Unfortunately, we can't split it anywhere. The PDS is a tree structure= and >> > the firmware expects to receive a well formatted tree. >> > >> > So, the easiest way to send it to the firmware is to split the tree >> > between each root nodes and send each subtree separately (see also the >> > comment above wfx_send_pds()). >> > >> > Anyway, someone has to cook this configuration before to send it to the >> > firmware. This could be done by a script outside of the kernel. Then we >> > could change the input format to simplify a bit the processing in the >> > kernel. >>=20 >> I think a binary file with TLV format would be much better, but I'm sure >> there also other good choises. >>=20 >> > However, the driver has already some users and I worry that changing >> > the input format would lead to a mess. >>=20 >> You can implement a script which converts the old format to the new >> format. And you can use different naming scheme in the new format so >> that we don't accidentally load the old format. And even better if you >> add a some kind of signature in the new format and give a proper error >> from the driver if it doesn't match. > > Ok. I am going to change the input format. I think the new function is > going to look like: > > int wfx_send_pds(struct wfx_dev *wdev, u8 *buf, size_t buf_len) > { > int ret; > int start =3D 0; > > if (buf[start] !=3D '{') { > dev_err(wdev->dev, "valid PDS start with '{'. Did you forget to compres= s it?\n"); > return -EINVAL; > } > while (start < buf_len) { > len =3D strnlen(buf + start, buf_len - start); > if (len > WFX_PDS_MAX_SIZE) { > dev_err(wdev->dev, "PDS chunk is too big (legacy format?)\n"); > return -EINVAL; > } > dev_dbg(wdev->dev, "send PDS '%s'\n", buf + start); > ret =3D wfx_hif_configuration(wdev, buf + start, len); > /* FIXME: Add error handling here */ > start +=3D len; > } > return 0; Did you read at all what I wrote above? Please ditch the ASCII format completely. --=20 https://patchwork.kernel.org/project/linux-wireless/list/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatc= hes