From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-2727985-1519127472-2-11503448373746540704 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.001, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='net', MailFrom='org' X-Spam-charsets: X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: linux-usb-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1519127471; b=j4Wec3s89tpvDvtZMKlUUCaEEVXV4KmCnPVLQDKjxppRAFF iqXq4SP3gSTkhQAE9LDa17VQ7YjqY3cmO6yaF+Vb+8ZF5Ef3DJwI8eNLbbvziUNU q3Pv1NwRN+Plr330h7KvZzsEAJGxnT73xkK4sZqeP4I1lEKopdWJyJNU+mLol7s1 Jh6dDax+DxzqpPBqfcfrVLy5cLFX5Fm5gu7LZg+Dz6pHvwq66FF5V6zllOxIp2Gm svmMI1HAYOIKotGW0UkveLsSP2qnt2/9USQcNXZFWFtMZfhjwfTlS3SBJP0wwGuc hfkcJyC0u//4gyOV5ZD1QnYTDjWulVad7EiCTBw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id:sender :list-id; s=arctest; t=1519127471; bh=nbY2g7DdpM1oHCrKHEno3Fw/dj A7KXatjeCMY6aji8I=; b=q6Zoq+maSm8N1vJSVEPJ5INLnmzrZzyTxCjrR0KNGF 2qr4bsE53Bai0UkuGZxUtroiF2VlWoWpAj6qb8Tjd5GfRwnvwkCK7HppPtdCaiet alLVnFqPRKGKDUVGSVOWtWIwjzYe9zex4udwm9QwATs5KuEEioQg2y22bQsRu8T+ AHZiOdqDJT4Hz0vgw5gQxvZgqd/dPsNivAJ0Y9ZAySaJxmh7SyRfEFYGnqKiKqqa t320ek0pTBginailEsY1EuIZ3Nhpj64ybVhkYte+4ehua/GSTkjOsWuceAjzFrPT tRaGpto0EVeujYeeoSx85KP9FFh7Z7S5QR+quqD4Vejg== ARC-Authentication-Results: i=1; mx1.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=g0hl1n.net; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-usb-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=g0hl1n.net header.result=pass header_is_org_domain=yes Authentication-Results: mx1.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=g0hl1n.net; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-usb-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=g0hl1n.net header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751472AbeBTLu4 (ORCPT ); Tue, 20 Feb 2018 06:50:56 -0500 Received: from relay12.alfahosting-server.de ([109.237.142.232]:5252 "EHLO relay12.alfahosting-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751435AbeBTLuz (ORCPT ); Tue, 20 Feb 2018 06:50:55 -0500 X-Remote-Spam-DCC: : X-Remote-Spam-Level: X-Remote-Spam-Status: No, score=-1000.0 required=7.0 tests=BAYES_50,D_SENT_WITH_SASL autolearn=disabled version=3.2.5 From: Richard Leitner To: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Cc: gregkh@linuxfoundation.org, stern@rowland.harvard.edu, linux@roeck-us.net, mathias.nyman@linux.intel.com, johan@kernel.org, felipe.balbi@linux.intel.com, ekorenevsky@gmail.com, peter.chen@nxp.com, drake@endlessm.com, joe@perches.com, Richard Leitner Subject: [PATCH v2] usb: core: introduce per-port over-current counters Date: Tue, 20 Feb 2018 12:50:33 +0100 Message-Id: <20180220115033.29496-1-dev@g0hl1n.net> X-Mailer: git-send-email 2.11.0 Sender: linux-usb-owner@vger.kernel.org X-Mailing-List: linux-usb@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: From: Richard Leitner For some userspace applications information on the number of over-current conditions at specific USB hub ports is relevant. In our case we have a series of USB hardware (using the cp210x driver) which communicates using a proprietary protocol. These devices sometimes trigger an over-current situation on some hubs. In case of such an over-current situation the USB devices offer an interface for reducing the max used power. As these conditions are quite rare and imply performance reductions of the device we don't want to reduce the max power always. Therefore give user-space applications the possibility to react adequately by introducing an over_current_counter in the usb port struct which is exported via sysfs. Signed-off-by: Richard Leitner --- Tested on an i.MX6DL based board Changes v2: - rename oc_count to over_current_count - add entry to Documentation/ABI - add detailled description to commit message --- Documentation/ABI/testing/sysfs-bus-usb | 9 +++++++++ drivers/usb/core/hub.c | 4 +++- drivers/usb/core/hub.h | 1 + drivers/usb/core/port.c | 10 ++++++++++ 4 files changed, 23 insertions(+), 1 deletion(-) diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb index 0bd731cbb50c..27020293c85b 100644 --- a/Documentation/ABI/testing/sysfs-bus-usb +++ b/Documentation/ABI/testing/sysfs-bus-usb @@ -189,6 +189,15 @@ Description: The file will read "hotplug", "wired" and "not used" if the information is available, and "unknown" otherwise. +What: /sys/bus/usb/devices/.../(hub interface)/portX/over_current_count +Date: February 2018 +Contact: Richard Leitner +Description: + Most hubs are able to detect over-current situations on their + ports and report them to the kernel. This attribute is to expose + the number of over-current situation occurred on a specific port + to user space. This file will contain an unsigned int. + What: /sys/bus/usb/devices/.../(hub interface)/portX/usb3_lpm_permit Date: November 2015 Contact: Lu Baolu diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index c5c1f6cf3228..6f779b518e75 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -5104,8 +5104,10 @@ static void port_event(struct usb_hub *hub, int port1) if (portchange & USB_PORT_STAT_C_OVERCURRENT) { u16 status = 0, unused; + port_dev->over_current_count++; - dev_dbg(&port_dev->dev, "over-current change\n"); + dev_dbg(&port_dev->dev, "over-current change #%u\n", + port_dev->over_current_count); usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_OVER_CURRENT); msleep(100); /* Cool down */ diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h index 2a700ccc868c..78d7f4dad618 100644 --- a/drivers/usb/core/hub.h +++ b/drivers/usb/core/hub.h @@ -100,6 +100,7 @@ struct usb_port { unsigned int is_superspeed:1; unsigned int usb3_lpm_u1_permit:1; unsigned int usb3_lpm_u2_permit:1; + unsigned int over_current_count; }; #define to_usb_port(_dev) \ diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c index 1a01e9ad3804..6979bde87d31 100644 --- a/drivers/usb/core/port.c +++ b/drivers/usb/core/port.c @@ -41,6 +41,15 @@ static ssize_t connect_type_show(struct device *dev, } static DEVICE_ATTR_RO(connect_type); +static ssize_t over_current_count_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct usb_port *port_dev = to_usb_port(dev); + + return sprintf(buf, "%u\n", port_dev->over_current_count); +} +static DEVICE_ATTR_RO(over_current_count); + static ssize_t usb3_lpm_permit_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -109,6 +118,7 @@ static DEVICE_ATTR_RW(usb3_lpm_permit); static struct attribute *port_dev_attrs[] = { &dev_attr_connect_type.attr, + &dev_attr_over_current_count.attr, NULL, }; -- 2.11.0