From patchwork Thu Apr 14 13:09:20 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 562336 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4397CC4707F for ; Thu, 14 Apr 2022 13:57:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345054AbiDNNwt (ORCPT ); Thu, 14 Apr 2022 09:52:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50388 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344890AbiDNNot (ORCPT ); Thu, 14 Apr 2022 09:44:49 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7F86A39B86; Thu, 14 Apr 2022 06:40:32 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 87FC8612E6; Thu, 14 Apr 2022 13:40:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9BAD5C385A5; Thu, 14 Apr 2022 13:40:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649943632; bh=FgkMapFX7HltZgmcI/SyG9B6F5Hr6wX4JefuaCKEJaY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=y9C/tpYWxjqWnqLZOB0CVGSJieQecN+VSY9Q7XKB2Com9SzqfoUHRFXSNjDcCBVqX 5ANZS87dHNwNKtJ3Kh3XrMU0JuCszYHydrTosuA+iFh8an897d4iK35SoxeRBXfn/H 50l9SZj1tfxJ//v0kPurHhyQyN1qDmqhxA1eHmIk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dmitry Torokhov , Benjamin Tissoires , Jiri Kosina , Sasha Levin Subject: [PATCH 5.4 175/475] HID: i2c-hid: fix GET/SET_REPORT for unnumbered reports Date: Thu, 14 Apr 2022 15:09:20 +0200 Message-Id: <20220414110900.032809478@linuxfoundation.org> X-Mailer: git-send-email 2.35.2 In-Reply-To: <20220414110855.141582785@linuxfoundation.org> References: <20220414110855.141582785@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Dmitry Torokhov [ Upstream commit a5e5e03e94764148a01757b2fa4737d3445c13a6 ] Internally kernel prepends all report buffers, for both numbered and unnumbered reports, with report ID, therefore to properly handle unnumbered reports we should prepend it ourselves. For the same reason we should skip the first byte of the buffer when calling i2c_hid_set_or_send_report() which then will take care of properly formatting the transfer buffer based on its separate report ID argument along with report payload. [jkosina@suse.cz: finalize trimmed sentence in changelog as spotted by Benjamin] Fixes: 9b5a9ae88573 ("HID: i2c-hid: implement ll_driver transport-layer callbacks") Signed-off-by: Dmitry Torokhov Tested-by: Benjamin Tissoires Signed-off-by: Jiri Kosina Signed-off-by: Sasha Levin --- drivers/hid/i2c-hid/i2c-hid-core.c | 32 ++++++++++++++++++++++-------- 1 file changed, 24 insertions(+), 8 deletions(-) diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c index ac076ac73de5..1547b0ec6a11 100644 --- a/drivers/hid/i2c-hid/i2c-hid-core.c +++ b/drivers/hid/i2c-hid/i2c-hid-core.c @@ -622,6 +622,17 @@ static int i2c_hid_get_raw_report(struct hid_device *hid, if (report_type == HID_OUTPUT_REPORT) return -EINVAL; + /* + * In case of unnumbered reports the response from the device will + * not have the report ID that the upper layers expect, so we need + * to stash it the buffer ourselves and adjust the data size. + */ + if (!report_number) { + buf[0] = 0; + buf++; + count--; + } + /* +2 bytes to include the size of the reply in the query buffer */ ask_count = min(count + 2, (size_t)ihid->bufsize); @@ -643,6 +654,9 @@ static int i2c_hid_get_raw_report(struct hid_device *hid, count = min(count, ret_count - 2); memcpy(buf, ihid->rawbuf + 2, count); + if (!report_number) + count++; + return count; } @@ -659,17 +673,19 @@ static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf, mutex_lock(&ihid->reset_lock); - if (report_id) { - buf++; - count--; - } - + /* + * Note that both numbered and unnumbered reports passed here + * are supposed to have report ID stored in the 1st byte of the + * buffer, so we strip it off unconditionally before passing payload + * to i2c_hid_set_or_send_report which takes care of encoding + * everything properly. + */ ret = i2c_hid_set_or_send_report(client, report_type == HID_FEATURE_REPORT ? 0x03 : 0x02, - report_id, buf, count, use_data); + report_id, buf + 1, count - 1, use_data); - if (report_id && ret >= 0) - ret++; /* add report_id to the number of transfered bytes */ + if (ret >= 0) + ret++; /* add report_id to the number of transferred bytes */ mutex_unlock(&ihid->reset_lock);