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 X-Spam-Level: X-Spam-Status: No, score=-6.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 013B6C2D0DB for ; Mon, 27 Jan 2020 20:36:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B7DCA24679 for ; Mon, 27 Jan 2020 20:36:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="GA1c4pct" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726303AbgA0UgJ (ORCPT ); Mon, 27 Jan 2020 15:36:09 -0500 Received: from mail-qk1-f196.google.com ([209.85.222.196]:43534 "EHLO mail-qk1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726083AbgA0UgJ (ORCPT ); Mon, 27 Jan 2020 15:36:09 -0500 Received: by mail-qk1-f196.google.com with SMTP id j20so11020491qka.10 for ; Mon, 27 Jan 2020 12:36:08 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=jeIUpeh4Yswut4pRuWFrQhyeR8XRgwbORCyDxrSirrg=; b=GA1c4pctZziuKzjHaqUbZw8CZ7cznKcz/Djo1odwjZqRlUv50//rv8QeQKG8mm85vV xLDbdnsvXQxjrFOiz8GonJ6dTlUE/ONpuLmoD4K4CE5a18hHoAfAj2S/HkbCHhdRGjqU FDtLmECGn9MFWyLbsl1Xebva5+jFkZZRl+6zG7z3JECsHa0OenDd1tyW6fEH/+OUh0DI nqborKFlY4OJFFEgaQNOQbIVs1/yerR7ldDPBx9l2GQuzG9FRa2GDGJTjPcQD0AEnfig wOBWMpaCe0iRVlFMn61KkmVottLUe/ctdEbcl0RFjwoIe6fLsK2KZWvBVbAjKmsOtaUo XfnA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=jeIUpeh4Yswut4pRuWFrQhyeR8XRgwbORCyDxrSirrg=; b=NAY32eR7dEFeYiWChvjUxzd8Cg0RK987Tvl+JvYyrcQIhpDUDs/5XV14x8xRAL3jr3 0t4iK+OEl0B7sluk0eQZjVu5JWbUZpE+tuMxeB0sPbjckC5M8zbOu48PoVG+5fRwBst/ bgpqFqFWYwoidzcJYQE9XWbsaeRHeNty7Egk9T/Nb2IIvygw3PjK/okzMGsrSYBDJ62Y q5Ptr2LSUMfOYO4CZwlLW1jHO6IbiDxunvYmyGgknP8nnlADh9qSpXssWL+aBVjCmDRE Kp+s9bDJm8+7oX84cCvrqHtwNmEWFMp6Oys609iKVi80cPrhznrRavGT8FO3wcj0sa6h Iw/g== X-Gm-Message-State: APjAAAUL8crR7PhzqHjVnwuFkaAj6A3XSHy6nuIaYPUJ7mhX6lqlk8Vs 6kP29ESXr2Qr36vjDl6t+YaoLFYSxD/boV4m/51SObur X-Google-Smtp-Source: APXvYqw7ABIomcTod01LEWiv36/B+eHKp6E58DE3Jyq2CkSUUGJl+Hodd9V6tK4HbI4brmheCQJUKcjUmPLs8Sgo0tM= X-Received: by 2002:ae9:ef06:: with SMTP id d6mr18010698qkg.402.1580157368184; Mon, 27 Jan 2020 12:36:08 -0800 (PST) MIME-Version: 1.0 References: <20200125012105.59903-1-pmalani@chromium.org> <20200125012105.59903-2-pmalani@chromium.org> In-Reply-To: From: Enric Balletbo Serra Date: Mon, 27 Jan 2020 21:35:56 +0100 Message-ID: Subject: Re: [PATCH 1/4] platform/chrome: Add EC command msg wrapper To: Prashant Malani Cc: Enric Balletbo i Serra , Benson Leung , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Prashant, Missatge de Prashant Malani del dia dl., 27 de gen. 2020 a les 18:13: > > Hi Enric, > > On Mon, Jan 27, 2020 at 7:29 AM Enric Balletbo i Serra > wrote: > > > > Hi Prashant, > > > > Many thanks for this patch. > > > > On 25/1/20 2:21, Prashant Malani wrote: > > > Many callers of cros_ec_cmd_xfer_status() use a similar set up of > > > allocating and filling a message buffer and then copying any received > > > data to a target buffer. > > > > > > > cros_ec_cmd_xfer_status is already a wrapper, I dislike the idea of having three > > ways to do the same (cros_ec_cmd_xfer, cros_ec_cmd_xfer_status and this new > > one). I like the idea of have a wrapper that embeds the message allocation but > > we should not confuse users with different calls that does the same. > Yes, my intention was to eventually replace all the xfer_status() > call-sites to use the new wrapper, and then get rid of xfer_status > completely. > > > > So, I am for a change like this but I'd like to have all the users calling the > > same wrapper (unless there is a good reason to not use it). A proposed roadmap > > (to be discussed) for this would be. > > > > 1. Replace all the remaining "cros_ec_cmd_xfer" calls with > > "cros_ec_cmd_xfer_status". > > 2. Modify cros_ec_cmd_xfer_status to embed the message allocation. > > How about the following alteration the the roadmap: > - Introducing the new wrapper. > - Replacing all remaining cros_ec_cmd_xfer/cros_ec_cmd_xfer_status to > use the new wrapper. > - Deleting cros_ec_cmd_xfer and cros_ec_cmd_xfer_status ? > My thinking is that this would mean fewer changes at the call-sites > compared to the original roadmap (in the original roadmap, one would > first have to modify calls to use cros_ec_cmd_xfer_status(), and then > modify them again when cros_ec_cmd_xfer_status() itself is modified to > include message allocation). > Sounds like we have a plan, looks good to me. Cheers, Enric > That said I don't have any strong preference, so either would work. > > Best regards, > > > > Thanks, > > Enric > > > > > > > Create a utility function that performs this setup so that callers can > > > use this function instead. > > > > > > Signed-off-by: Prashant Malani > > > --- > > > drivers/platform/chrome/cros_ec_proto.c | 53 +++++++++++++++++++++ > > > include/linux/platform_data/cros_ec_proto.h | 5 ++ > > > 2 files changed, 58 insertions(+) > > > > > > diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c > > > index da1b1c4504333..8ef3b7d27d260 100644 > > > --- a/drivers/platform/chrome/cros_ec_proto.c > > > +++ b/drivers/platform/chrome/cros_ec_proto.c > > > @@ -5,6 +5,7 @@ > > > > > > #include > > > #include > > > +#include > > > #include > > > #include > > > #include > > > @@ -570,6 +571,58 @@ int cros_ec_cmd_xfer_status(struct cros_ec_device *ec_dev, > > > } > > > EXPORT_SYMBOL(cros_ec_cmd_xfer_status); > > > > > > +/** > > > + * cros_ec_send_cmd_msg() - Utility function to send commands to ChromeOS EC. > > > + * @ec: EC device struct. > > > + * @version: Command version number (often 0). > > > + * @command: Command ID including offset. > > > + * @outdata: Data to be sent to the EC. > > > + * @outsize: Size of the &outdata buffer. > > > + * @indata: Data to be received from the EC. > > > + * @insize: Size of the &indata buffer. > > > + * > > > + * This function is a wrapper around &cros_ec_cmd_xfer_status, and performs > > > + * some of the common work involved with sending a command to the EC. This > > > + * includes allocating and filling up a &struct cros_ec_command message buffer, > > > + * and copying the received data to another buffer. > > > + * > > > + * Return: The number of bytes transferred on success or negative error code. > > > + */ > > > +int cros_ec_send_cmd_msg(struct cros_ec_device *ec, unsigned int version, > > > + unsigned int command, void *outdata, > > > + unsigned int outsize, void *indata, > > > + unsigned int insize) > > > +{ > > > + struct cros_ec_command *msg; > > > + int ret; > > > + > > > + msg = kzalloc(sizeof(*msg) + max(outsize, insize), GFP_KERNEL); > > > + if (!msg) > > > + return -ENOMEM; > > > + > > > + msg->version = version; > > > + msg->command = command; > > > + msg->outsize = outsize; > > > + msg->insize = insize; > > > + > > > + if (outdata && outsize > 0) > > > + memcpy(msg->data, outdata, outsize); > > > + > > > + ret = cros_ec_cmd_xfer_status(ec, msg); > > > + if (ret < 0) { > > > + dev_warn(ec->dev, "Command failed: %d\n", msg->result); > > > + goto cleanup; > > > + } > > > + > > > + if (insize) > > > + memcpy(indata, msg->data, insize); > > > + > > > +cleanup: > > > + kfree(msg); > > > + return ret; > > > +} > > > +EXPORT_SYMBOL(cros_ec_send_cmd_msg); > > > + > > > static int get_next_event_xfer(struct cros_ec_device *ec_dev, > > > struct cros_ec_command *msg, > > > struct ec_response_get_next_event_v1 *event, > > > diff --git a/include/linux/platform_data/cros_ec_proto.h b/include/linux/platform_data/cros_ec_proto.h > > > index 30098a5515231..166ce26bdd79e 100644 > > > --- a/include/linux/platform_data/cros_ec_proto.h > > > +++ b/include/linux/platform_data/cros_ec_proto.h > > > @@ -201,6 +201,11 @@ int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev, > > > int cros_ec_cmd_xfer_status(struct cros_ec_device *ec_dev, > > > struct cros_ec_command *msg); > > > > > > +int cros_ec_send_cmd_msg(struct cros_ec_device *ec_dev, unsigned int version, > > > + unsigned int command, void *outdata, > > > + unsigned int outsize, void *indata, > > > + unsigned int insize); > > > + > > > int cros_ec_register(struct cros_ec_device *ec_dev); > > > > > > int cros_ec_unregister(struct cros_ec_device *ec_dev); > > >