From patchwork Mon Sep 11 08:24:56 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joshua Yeong X-Patchwork-Id: 13379012 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 98B4BEE57DF for ; Mon, 11 Sep 2023 08:25:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=dwt+DuL2k+qPzFhHZX2vwcrFBiNCE3ImDc//ljiCY5c=; b=Codk4yHoPl/ikY dH+//2CVEWD3CnyIfefiWefP4xrUQDpF5uRXps18GeNxJ6PhyoMKSd/vmwtzkeC6sdwcpY+WEyaRF ZVesnu+h42g1Fpv4HK1hezaLeAOAmbIoHTVHfelZ+lSsVANuIytG1cV8iDgLi+6MYCUQIaULZMNmJ 99ltN6vh0S9wJYR2NBjBXdN+udimq3DxzakP/3bXe+dKiuL6XWhxGne94DLBupZtzL98gzH3kdSME tsb4fWrgueTJBVwTwh6jrvi6wuvOoz0xVxJhoFPgUQurybcd0MLvKFxwVIyT9sz6zgmXHnZ4HL0Gx JDtEZZ0sCBs6QSsShOaw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qfcEe-00HXO0-12; Mon, 11 Sep 2023 08:25:32 +0000 Received: from ex01.ufhost.com ([61.152.239.75]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qfcEb-00HXNQ-2R for linux-i3c@lists.infradead.org; Mon, 11 Sep 2023 08:25:31 +0000 Received: from EXMBX166.cuchost.com (unknown [175.102.18.54]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "EXMBX166", Issuer "EXMBX166" (not verified)) by ex01.ufhost.com (Postfix) with ESMTP id E045E24E2C2; Mon, 11 Sep 2023 16:25:21 +0800 (CST) Received: from EXMBX066.cuchost.com (172.16.7.66) by EXMBX166.cuchost.com (172.16.6.76) with Microsoft SMTP Server (TLS) id 15.0.1497.42; Mon, 11 Sep 2023 16:25:19 +0800 Received: from localhost.localdomain (202.188.176.82) by EXMBX066.cuchost.com (172.16.6.66) with Microsoft SMTP Server (TLS) id 15.0.1497.42; Mon, 11 Sep 2023 16:25:16 +0800 From: Joshua Yeong To: CC: , , "Joshua Yeong" Subject: [PATCH 1/1] i3c: Add fallback method for GETMXDS CCC Date: Mon, 11 Sep 2023 16:24:56 +0800 Message-ID: <20230911082456.23239-2-joshua.yeong@starfivetech.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230911082456.23239-1-joshua.yeong@starfivetech.com> References: <20230911082456.23239-1-joshua.yeong@starfivetech.com> MIME-Version: 1.0 X-Originating-IP: [202.188.176.82] X-ClientProxiedBy: EXCAS062.cuchost.com (172.16.6.22) To EXMBX066.cuchost.com (172.16.6.66) X-YovoleRuleAgent: yovoleflag X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230911_012530_082011_6E03BCAD X-CRM114-Status: GOOD ( 15.46 ) X-BeenThere: linux-i3c@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-i3c" Errors-To: linux-i3c-bounces+linux-i3c=archiver.kernel.org@lists.infradead.org Some I3C hardware will report error when incorrect length is received from device. GETMXDS CCC are availble in 2 formats; without turnaround time (format 1) and with turnaround time (format 2). There is no mechanics to determine which format is supported by device. In case sending GETMXDS CCC format 2 resulted failure, try sending GETMXDS CCC format 1 instead. Signed-off-by: Joshua Yeong --- drivers/i3c/master.c | 33 ++++++++++++++++++++++++++++----- include/linux/i3c/ccc.h | 17 +++++++++++++++-- 2 files changed, 43 insertions(+), 7 deletions(-) diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c index 87283e4a4607..084f64bef155 100644 --- a/drivers/i3c/master.c +++ b/drivers/i3c/master.c @@ -1088,10 +1088,37 @@ static int i3c_master_getmxds_locked(struct i3c_master_controller *master, struct i3c_device_info *info) { struct i3c_ccc_getmxds *getmaxds; + struct i3c_ccc_getmxds_turnaround *getmaxds_ta; struct i3c_ccc_cmd_dest dest; struct i3c_ccc_cmd cmd; int ret; + getmaxds_ta = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, + sizeof(*getmaxds_ta)); + if (!getmaxds_ta) + return -ENOMEM; + + i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMXDS, &dest, 1); + ret = i3c_master_send_ccc_cmd_locked(master, &cmd); + if (ret) { + goto alternative; + } + + if (dest.payload.len != 2 && dest.payload.len != 5) { + ret = -EIO; + goto out; + } + + info->max_read_ds = getmaxds_ta->maxrd; + info->max_write_ds = getmaxds_ta->maxwr; + if (dest.payload.len == 5) + info->max_read_turnaround = getmaxds_ta->maxrdturn[0] | + ((u32)getmaxds_ta->maxrdturn[1] << 8) | + ((u32)getmaxds_ta->maxrdturn[2] << 16); + +alternative: + i3c_ccc_cmd_dest_cleanup(&dest); + getmaxds = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getmaxds)); if (!getmaxds) @@ -1102,17 +1129,13 @@ static int i3c_master_getmxds_locked(struct i3c_master_controller *master, if (ret) goto out; - if (dest.payload.len != 2 && dest.payload.len != 5) { + if (dest.payload.len != 2) { ret = -EIO; goto out; } info->max_read_ds = getmaxds->maxrd; info->max_write_ds = getmaxds->maxwr; - if (dest.payload.len == 5) - info->max_read_turnaround = getmaxds->maxrdturn[0] | - ((u32)getmaxds->maxrdturn[1] << 8) | - ((u32)getmaxds->maxrdturn[2] << 16); out: i3c_ccc_cmd_dest_cleanup(&dest); diff --git a/include/linux/i3c/ccc.h b/include/linux/i3c/ccc.h index ad59a4ae60d1..50ed41d4d5a1 100644 --- a/include/linux/i3c/ccc.h +++ b/include/linux/i3c/ccc.h @@ -269,14 +269,27 @@ enum i3c_tsco { #define I3C_CCC_MAX_SDR_FSCL(x) ((x) & I3C_CCC_MAX_SDR_FSCL_MASK) /** - * struct i3c_ccc_getmxds - payload passed to GETMXDS CCC + * struct i3c_ccc_getmxds - payload passed to GETMXDS CCC without turnaround + * (format 1) + * + * @maxwr: write limitations + * @maxrd: read limitations + */ +struct i3c_ccc_getmxds { + u8 maxwr; + u8 maxrd; +} __packed; + +/** + * struct i3c_ccc_getmxds_ta - payload passed to GETMXDS CCC with turnaround + * (format 2) * * @maxwr: write limitations * @maxrd: read limitations * @maxrdturn: maximum read turn-around expressed micro-seconds and * little-endian formatted */ -struct i3c_ccc_getmxds { +struct i3c_ccc_getmxds_turnaround { u8 maxwr; u8 maxrd; u8 maxrdturn[3];