From patchwork Mon Nov 16 20:11:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Prashant Malani X-Patchwork-Id: 11910711 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B661E15E6 for ; Mon, 16 Nov 2020 20:12:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 963B521D7E for ; Mon, 16 Nov 2020 20:12:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="IFLoEzJj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726382AbgKPUMs (ORCPT ); Mon, 16 Nov 2020 15:12:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41982 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726268AbgKPUMs (ORCPT ); Mon, 16 Nov 2020 15:12:48 -0500 Received: from mail-pf1-x42b.google.com (mail-pf1-x42b.google.com [IPv6:2607:f8b0:4864:20::42b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1C0ABC0613CF for ; Mon, 16 Nov 2020 12:12:48 -0800 (PST) Received: by mail-pf1-x42b.google.com with SMTP id c20so15203359pfr.8 for ; Mon, 16 Nov 2020 12:12:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=z8GPAvDAlSfkoQSjuEJ0bvEZ1CcveAaL6tNvl68OKZs=; b=IFLoEzJjWLLImXDDnVTRmjqX2AUVgv99PSEiGsPVR7Mxru8xFo8jKmIcsZ/BgBbVQB Exg8WzaGGACqVitl1qQN+/QX/vGJpnesS3dyDTUhboJ7+Dqyq30YW/n2bK43Al1s7Zkw IIal/QxDNEMrfVCqrByl88yBlHdJ0P0JlsBdg= 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=z8GPAvDAlSfkoQSjuEJ0bvEZ1CcveAaL6tNvl68OKZs=; b=IjTO+QuxZTiw0IoYvWPYcknQOi9nXw53HxL8XhjCbLuZeo/YpjZrCoHNbmMnQ9pmIj Kk6TQB9CmiwgaTqGuJwFELo4SLqw70vmESVYXeBzaT2dk8FNpGyAOSQRQLJkSPmd7bg7 hCMVRLkQMofhGSnHWOWH3TXKkLfKLCHCsZSAb1q0Yso7EYPe3yK3A1fIEwvQCsW1pK04 GJMBjfdjKwkyssEisBqgpmDJL//bumZSA0mNZa3zxMyQfec5QcQYeGLU6wDOerLZ+iTb QUH3Czu81tEnGaL3Q+/2oEyJSU8xivC28MST2ZGEWuaWyYCGpWpH98GY+MRBhbwBDJBe jX0Q== X-Gm-Message-State: AOAM533M/vhK71EKRf1BJMRTpKzddhTMSUk8xsvB+hxngXd2jzY8Nv1i EXrNzbYbWOQGBvYIrZXZejh9Cw== X-Google-Smtp-Source: ABdhPJz5S3hGVam/Wc98BfMyrQ4HACiQaUSbziR0hTykBa3o3ugwXnC4LQLkriyfxwRGosyBCvHIng== X-Received: by 2002:a17:90a:db54:: with SMTP id u20mr590997pjx.189.1605557567686; Mon, 16 Nov 2020 12:12:47 -0800 (PST) Received: from pmalani2.mtv.corp.google.com ([2620:15c:202:201:a28c:fdff:fef0:49dd]) by smtp.gmail.com with ESMTPSA id a12sm234577pjh.48.2020.11.16.12.12.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 16 Nov 2020 12:12:47 -0800 (PST) From: Prashant Malani To: linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, gregkh@linuxfoundation.org, heikki.krogerus@linux.intel.com, enric.balletbo@collabora.com Cc: Prashant Malani Subject: [PATCH v3 03/11] usb: typec: Add plug num_altmodes sysfs attr Date: Mon, 16 Nov 2020 12:11:42 -0800 Message-Id: <20201116201150.2919178-4-pmalani@chromium.org> X-Mailer: git-send-email 2.29.2.299.gdc1121823c-goog In-Reply-To: <20201116201150.2919178-1-pmalani@chromium.org> References: <20201116201150.2919178-1-pmalani@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Add a field to the typec_plug struct to record the number of available altmodes as well as the corresponding sysfs attribute to expose this to userspace. This allows userspace to determine whether there are any remaining alternate modes left to be registered by the kernel driver. It can begin executing any policy state machine after all available alternate modes have been registered with the connector class framework. This value is set to "-1" initially, signifying that a valid number of alternate modes haven't been set for the plug. The sysfs file remains hidden as long as the attribute value is -1. We re-use the partner attribute for number_of_alternate_modes since the usage and name is similar, and update the corresponding *_show() command to support both partner and plugs. Signed-off-by: Prashant Malani Reviewed-by: Heikki Krogerus --- Changes in v3: - Re-arranged patch order and combined it with related series of patches. No version v2. Documentation/ABI/testing/sysfs-class-typec | 9 +++ drivers/usb/typec/class.c | 77 ++++++++++++++++++++- include/linux/usb/typec.h | 1 + 3 files changed, 85 insertions(+), 2 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-class-typec b/Documentation/ABI/testing/sysfs-class-typec index 73ac7b461ae5..29eccf5fb8ed 100644 --- a/Documentation/ABI/testing/sysfs-class-typec +++ b/Documentation/ABI/testing/sysfs-class-typec @@ -204,6 +204,15 @@ Description: - type-c - captive +What: /sys/class/typec/-/number_of_alternate_modes +Date: November 2020 +Contact: Prashant Malani +Description: + Shows the number of alternate modes which are advertised by the plug + associated with a particular cable during Power Delivery discovery. + This file remains hidden until a value greater than or equal to 0 + is set by Type C port driver. + What: /sys/class/typec/-cable/identity/ Date: April 2017 Contact: Heikki Krogerus diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c index c7412ddbd311..e68798599ca8 100644 --- a/drivers/usb/typec/class.c +++ b/drivers/usb/typec/class.c @@ -18,6 +18,7 @@ struct typec_plug { struct device dev; enum typec_plug_index index; struct ida mode_ids; + int num_altmodes; }; struct typec_cable { @@ -536,9 +537,21 @@ static DEVICE_ATTR_RO(supports_usb_power_delivery); static ssize_t number_of_alternate_modes_show(struct device *dev, struct device_attribute *attr, char *buf) { - struct typec_partner *p = to_typec_partner(dev); + struct typec_partner *partner; + struct typec_plug *plug; + int num_altmodes; + + if (is_typec_partner(dev)) { + partner = to_typec_partner(dev); + num_altmodes = partner->num_altmodes; + } else if (is_typec_plug(dev)) { + plug = to_typec_plug(dev); + num_altmodes = plug->num_altmodes; + } else { + return 0; + } - return sysfs_emit(buf, "%d\n", p->num_altmodes); + return sysfs_emit(buf, "%d\n", num_altmodes); } static DEVICE_ATTR_RO(number_of_alternate_modes); @@ -726,11 +739,70 @@ static void typec_plug_release(struct device *dev) kfree(plug); } +static struct attribute *typec_plug_attrs[] = { + &dev_attr_number_of_alternate_modes.attr, + NULL +}; + +static umode_t typec_plug_attr_is_visible(struct kobject *kobj, struct attribute *attr, int n) +{ + struct typec_plug *plug = to_typec_plug(kobj_to_dev(kobj)); + + if (attr == &dev_attr_number_of_alternate_modes.attr) { + if (plug->num_altmodes < 0) + return 0; + } + + return attr->mode; +} + +static struct attribute_group typec_plug_group = { + .is_visible = typec_plug_attr_is_visible, + .attrs = typec_plug_attrs +}; + +static const struct attribute_group *typec_plug_groups[] = { + &typec_plug_group, + NULL +}; + static const struct device_type typec_plug_dev_type = { .name = "typec_plug", + .groups = typec_plug_groups, .release = typec_plug_release, }; +/** + * typec_plug_set_num_altmodes - Set the number of available plug altmodes + * @plug: The plug to be updated. + * @num_altmodes: The number of altmodes we want to specify as available. + * + * This routine is used to report the number of alternate modes supported by the + * plug. This value is *not* enforced in alternate mode registration routines. + * + * @plug.num_altmodes is set to -1 on plug registration, denoting that + * a valid value has not been set for it yet. + * + * Returns 0 on success or negative error number on failure. + */ +int typec_plug_set_num_altmodes(struct typec_plug *plug, int num_altmodes) +{ + int ret; + + if (num_altmodes < 0) + return -EINVAL; + + plug->num_altmodes = num_altmodes; + ret = sysfs_update_group(&plug->dev.kobj, &typec_plug_group); + if (ret < 0) + return ret; + + sysfs_notify(&plug->dev.kobj, NULL, "number_of_alternate_modes"); + + return 0; +} +EXPORT_SYMBOL_GPL(typec_plug_set_num_altmodes); + /** * typec_plug_register_altmode - Register USB Type-C Cable Plug Alternate Mode * @plug: USB Type-C Cable Plug that supports the alternate mode @@ -776,6 +848,7 @@ struct typec_plug *typec_register_plug(struct typec_cable *cable, sprintf(name, "plug%d", desc->index); ida_init(&plug->mode_ids); + plug->num_altmodes = -1; plug->index = desc->index; plug->dev.class = typec_class; plug->dev.parent = &cable->dev; diff --git a/include/linux/usb/typec.h b/include/linux/usb/typec.h index bc6b1a71cb8a..54475323f83b 100644 --- a/include/linux/usb/typec.h +++ b/include/linux/usb/typec.h @@ -130,6 +130,7 @@ int typec_partner_set_num_altmodes(struct typec_partner *partner, int num_altmod struct typec_altmode *typec_partner_register_altmode(struct typec_partner *partner, const struct typec_altmode_desc *desc); +int typec_plug_set_num_altmodes(struct typec_plug *plug, int num_altmodes); struct typec_altmode *typec_plug_register_altmode(struct typec_plug *plug, const struct typec_altmode_desc *desc);