From patchwork Thu Jul 29 10:26:03 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Zaidman X-Patchwork-Id: 489547 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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 7B2C4C4320A for ; Thu, 29 Jul 2021 10:27:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5AA7560462 for ; Thu, 29 Jul 2021 10:27:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235445AbhG2K10 (ORCPT ); Thu, 29 Jul 2021 06:27:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58918 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235155AbhG2K1Z (ORCPT ); Thu, 29 Jul 2021 06:27:25 -0400 Received: from mail-wm1-x32a.google.com (mail-wm1-x32a.google.com [IPv6:2a00:1450:4864:20::32a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D7CB2C061757; Thu, 29 Jul 2021 03:27:22 -0700 (PDT) Received: by mail-wm1-x32a.google.com with SMTP id u15-20020a05600c19cfb02902501bdb23cdso6495731wmq.0; Thu, 29 Jul 2021 03:27:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=/r4EMpOiWcNrACqTgelxOYdk1xzSfi6/Cy6AgoDN22Y=; b=Qy7yfveaKvQAIF2AvFybTcHBlX5Ow+E0pCDwqqfj+E8R7cpMrapK6IqD6ACX2irdfT cQsVlHNSo841rZ/vkfwJntF44EmLAysG8PZfavHv0YxbfsHMRhm5NOBimG/dUu38lgzU Jo3cyJ8rqgwuJayZkWRZ7HRGDBJl4lyeh1Kc9POJoIep3UQ8Rz7m4bgzwajTgJ5iWeEO spCCtrH+KE1/FYfBIOpsVv+bO0H5/8UBSD2zhquwA+BoZT3FSvbDAKlM0NY4SSIUZvz0 SK/DbIiC+TyjMnXQS+aaLQXb0YBAzC4Bf3Ih6hb181zzf8e9/CfChBatfvhmoyM7FY52 B2KQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=/r4EMpOiWcNrACqTgelxOYdk1xzSfi6/Cy6AgoDN22Y=; b=VajPgtglzM4EoSntNk/c+b2OwlNJm60i/Gm90kA7D0T+l0rzaoRenApF05vGrLycn6 7Jm9mGSs6KATbqbeWDKtCt9FfP3YeJQLxWk8qLXmyEJ1tVcb/XPRhbIy5OX+2EWPIIbY BygRYeBQbiRiBbdq2igkF9b37n5CPNBCeiwSWXIl7u9wD2a3fvQ+ZgEj8YJKu1oQA3LH K0crAj52ngc/n/xhQ517fZcrS1kLaqRNhKp6WLve9bL//zcgF2nu0iZbn/h5ntxcS9rm VHDMWTHTFI5+DFdmOBuCy5pT0/4UE/ol+xqp7a4bJT8PQaAaAuLeemjjFn4UeW3TTg0E 67/A== X-Gm-Message-State: AOAM5304j6OWoP6hjYDbUM6IBdGBnWlUTCF1peipXNjKsSk8z+mLxwnL Tx9fpyFcyu+/ruU8+rIZ/wU= X-Google-Smtp-Source: ABdhPJwpOxPu9pntuzs0c5YuvjJxhVSBEzf/L50+L72rf1Ve1FbdpyUm+S1f5kyP2b7FC0p5kVaCDA== X-Received: by 2002:a7b:c399:: with SMTP id s25mr13825686wmj.180.1627554441427; Thu, 29 Jul 2021 03:27:21 -0700 (PDT) Received: from michael-VirtualBox.xsight.ent ([31.168.255.170]) by smtp.googlemail.com with ESMTPSA id u2sm9441420wmm.37.2021.07.29.03.27.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 29 Jul 2021 03:27:20 -0700 (PDT) From: Michael Zaidman To: jikos@kernel.org, benjamin.tissoires@redhat.com, aaron.jones@ftdichip.com Cc: linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, linux-i2c@vger.kernel.org, Michael Zaidman Subject: [PATCH v2] HID: ft260: fix device removal due to USB disconnect Date: Thu, 29 Jul 2021 13:26:03 +0300 Message-Id: <20210729102603.3844-1-michael.zaidman@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org This commit fixes a functional regression introduced by the commit 82f09a637dd3 ("HID: ft260: improve error handling of ft260_hid_feature_report_get()") when upon USB disconnect, the FTDI FT260 i2c device is still available within the /dev folder. In my company's product, where the host USB to FT260 USB connection is hard-wired in the PCB, the issue is not reproducible. To reproduce it, I used the VirtualBox Ubuntu 20.04 VM and the UMFT260EV1A development module for the FTDI FT260 chip: Plug the UMFT260EV1A module into a USB port and attach it to VM. The VM shows 2 i2c devices under the /dev: michael@michael-VirtualBox:~$ ls /dev/i2c-* /dev/i2c-0 /dev/i2c-1 The i2c-0 is not related to the FTDI FT260: michael@michael-VirtualBox:~$ cat /sys/bus/i2c/devices/i2c-0/name SMBus PIIX4 adapter at 4100 The i2c-1 is created by hid-ft260.ko: michael@michael-VirtualBox:~$ cat /sys/bus/i2c/devices/i2c-1/name FT260 usb-i2c bridge on hidraw1 Now, detach the FTDI FT260 USB device from VM. We expect the /dev/i2c-1 to disappear, but it's still here: michael@michael-VirtualBox:~$ ls /dev/i2c-* /dev/i2c-0 /dev/i2c-1 And the kernel log shows: [ +0.001202] usb 2-2: USB disconnect, device number 3 [ +0.000109] ft260 0003:0403:6030.0002: failed to retrieve system status [ +0.000316] ft260 0003:0403:6030.0003: failed to retrieve system status It happens because the commit 82f09a637dd3 changed the ft260_get_system_config() return logic. This caused the ft260_is_interface_enabled() to exit with error upon the FT260 device USB disconnect, which in turn, aborted the ft260_remove() before deleting the FT260 i2c device and cleaning its sysfs stuff. This commit restores the FT260 USB removal functionality and improves the ft260_is_interface_enabled() code to handle correctly all chip modes defined by the device interface configuration pins DCNF0 and DCNF1. Signed-off-by: Michael Zaidman Acked-by: Aaron Jones (FTDI-UK) --- drivers/hid/hid-ft260.c | 23 +++++++---------------- 1 file changed, 7 insertions(+), 16 deletions(-) diff --git a/drivers/hid/hid-ft260.c b/drivers/hid/hid-ft260.c index f43a8406cb9a..e73776ae6976 100644 --- a/drivers/hid/hid-ft260.c +++ b/drivers/hid/hid-ft260.c @@ -742,7 +742,7 @@ static int ft260_is_interface_enabled(struct hid_device *hdev) int ret; ret = ft260_get_system_config(hdev, &cfg); - if (ret) + if (ret < 0) return ret; ft260_dbg("interface: 0x%02x\n", interface); @@ -754,23 +754,16 @@ static int ft260_is_interface_enabled(struct hid_device *hdev) switch (cfg.chip_mode) { case FT260_MODE_ALL: case FT260_MODE_BOTH: - if (interface == 1) { + if (interface == 1) hid_info(hdev, "uart interface is not supported\n"); - return 0; - } - ret = 1; + else + ret = 1; break; case FT260_MODE_UART: - if (interface == 0) { - hid_info(hdev, "uart is unsupported on interface 0\n"); - ret = 0; - } + hid_info(hdev, "uart interface is not supported\n"); break; case FT260_MODE_I2C: - if (interface == 1) { - hid_info(hdev, "i2c is unsupported on interface 1\n"); - ret = 0; - } + ret = 1; break; } return ret; @@ -1004,11 +997,9 @@ static int ft260_probe(struct hid_device *hdev, const struct hid_device_id *id) static void ft260_remove(struct hid_device *hdev) { - int ret; struct ft260_device *dev = hid_get_drvdata(hdev); - ret = ft260_is_interface_enabled(hdev); - if (ret <= 0) + if (!dev) return; sysfs_remove_group(&hdev->dev.kobj, &ft260_attr_group);