From mboxrd@z Thu Jan 1 00:00:00 1970 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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT autolearn=unavailable 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 A1645C43613 for ; Mon, 24 Jun 2019 10:01:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7774120848 for ; Mon, 24 Jun 2019 10:01:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729030AbfFXJ6f (ORCPT ); Mon, 24 Jun 2019 05:58:35 -0400 Received: from mga11.intel.com ([192.55.52.93]:44388 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729018AbfFXJ6f (ORCPT ); Mon, 24 Jun 2019 05:58:35 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 24 Jun 2019 02:58:33 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.63,411,1557212400"; d="scan'208";a="182604821" Received: from kuha.fi.intel.com ([10.237.72.189]) by fmsmga001.fm.intel.com with SMTP; 24 Jun 2019 02:58:28 -0700 Received: by kuha.fi.intel.com (sSMTP sendmail emulation); Mon, 24 Jun 2019 12:58:27 +0300 Date: Mon, 24 Jun 2019 12:58:27 +0300 From: Heikki Krogerus To: Chunfeng Yun Cc: Rob Herring , Greg Kroah-Hartman , Mark Rutland , Matthias Brugger , Adam Thomson , Li Jun , Badhri Jagan Sridharan , Hans de Goede , Andy Shevchenko , Min Guo , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, Biju Das , Linus Walleij , Yu Chen , Nagarjuna Kristam , Felipe Balbi Subject: Re: [PATCH v7 09/10] usb: roles: add USB Type-B GPIO connector driver Message-ID: <20190624095827.GA6501@kuha.fi.intel.com> References: <1560242680-23844-1-git-send-email-chunfeng.yun@mediatek.com> <1560242680-23844-10-git-send-email-chunfeng.yun@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1560242680-23844-10-git-send-email-chunfeng.yun@mediatek.com> User-Agent: Mutt/1.12.0 (2019-05-25) Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Hi Chunfeng, On Tue, Jun 11, 2019 at 04:44:39PM +0800, Chunfeng Yun wrote: > Due to the requirement of usb-connector.txt binding, the old way > using extcon to support USB Dual-Role switch is now deprecated > when use Type-B connector. > This patch introduces a driver of Type-B connector which typically > uses an input GPIO to detect USB ID pin, and try to replace the > function provided by extcon-usb-gpio driver I'm sorry for asking this so late, but why is this driver a Type-B specific driver (I really thought somebody had already asked this question)? I don't see anything Type-B specific in the driver. Basically it looks to me like just a gpio based connection detection driver that would work fine with for example uAB connectors.. > Signed-off-by: Chunfeng Yun > Tested-by: Nagarjuna Kristam > --- > v7 changes: > 1. remove macro DEV_PMS_OPS suggested by Andy > 2. add tested-by Nagarjuna > > v6 changes: > 1. get usb-role-swtich by usb_role_switch_get() > > v5 changes: > 1. put usb_role_switch when error happens suggested by Biju > 2. don't treat bype-B connector as a virtual device suggested by Rob > > v4 changes: > 1. remove linux/gpio.h suggested by Linus > 2. put node when error happens > > v3 changes: > 1. treat bype-B connector as a virtual device; > 2. change file name again > > v2 changes: > 1. file name is changed > 2. use new compatible > --- > drivers/usb/roles/Kconfig | 11 ++ > drivers/usb/roles/Makefile | 1 + > drivers/usb/roles/typeb-conn-gpio.c | 284 ++++++++++++++++++++++++++++ ..It also drives me crazy that you've put this driver under this folder. It does not create a role switch so ideally it should not go under driver/usb/roles/. I think a better place for it would be drivers/usb/misc/, or actually, maybe it should go under drivers/usb/common/? Could you still rename the driver to something like "usb-gpio.c" or conn-gpio.c, or something else, and also move it under drivers/usb/misc/ or drivers/usb/common/? > 3 files changed, 296 insertions(+) > create mode 100644 drivers/usb/roles/typeb-conn-gpio.c > > diff --git a/drivers/usb/roles/Kconfig b/drivers/usb/roles/Kconfig > index f8b31aa67526..d1156e18a81a 100644 > --- a/drivers/usb/roles/Kconfig > +++ b/drivers/usb/roles/Kconfig > @@ -26,4 +26,15 @@ config USB_ROLES_INTEL_XHCI > To compile the driver as a module, choose M here: the module will > be called intel-xhci-usb-role-switch. > > +config TYPEB_CONN_GPIO > + tristate "USB Type-B GPIO Connector" USB GPIO connection detection driver? > + depends on GPIOLIB > + help > + The driver supports USB role switch between host and device via GPIO > + based USB cable detection, used typically if an input GPIO is used > + to detect USB ID pin. > + > + To compile the driver as a module, choose M here: the module will > + be called typeb-conn-gpio.ko > + > endif # USB_ROLE_SWITCH > diff --git a/drivers/usb/roles/Makefile b/drivers/usb/roles/Makefile > index 757a7d2797eb..5d5620d9d113 100644 > --- a/drivers/usb/roles/Makefile > +++ b/drivers/usb/roles/Makefile > @@ -3,3 +3,4 @@ > obj-$(CONFIG_USB_ROLE_SWITCH) += roles.o > roles-y := class.o > obj-$(CONFIG_USB_ROLES_INTEL_XHCI) += intel-xhci-usb-role-switch.o > +obj-$(CONFIG_TYPEB_CONN_GPIO) += typeb-conn-gpio.o > diff --git a/drivers/usb/roles/typeb-conn-gpio.c b/drivers/usb/roles/typeb-conn-gpio.c > new file mode 100644 > index 000000000000..e3fba1656069 > --- /dev/null > +++ b/drivers/usb/roles/typeb-conn-gpio.c > @@ -0,0 +1,284 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * USB Type-B GPIO Connector Driver > + * > + * Copyright (C) 2019 MediaTek Inc. > + * > + * Author: Chunfeng Yun > + * > + * Some code borrowed from drivers/extcon/extcon-usb-gpio.c > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#define USB_GPIO_DEB_MS 20 /* ms */ > +#define USB_GPIO_DEB_US ((USB_GPIO_DEB_MS) * 1000) /* us */ > + > +#define USB_CONN_IRQF \ > + (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT) > + > +struct usb_conn_info { > + struct device *dev; > + struct usb_role_switch *role_sw; > + enum usb_role last_role; > + struct regulator *vbus; > + struct delayed_work dw_det; > + unsigned long debounce_jiffies; > + > + struct gpio_desc *id_gpiod; > + struct gpio_desc *vbus_gpiod; > + int id_irq; > + int vbus_irq; > +}; > + > +/** > + * "DEVICE" = VBUS and "HOST" = !ID, so we have: > + * Both "DEVICE" and "HOST" can't be set as active at the same time > + * so if "HOST" is active (i.e. ID is 0) we keep "DEVICE" inactive > + * even if VBUS is on. > + * > + * Role | ID | VBUS > + * ------------------------------------ > + * [1] DEVICE | H | H > + * [2] NONE | H | L > + * [3] HOST | L | H > + * [4] HOST | L | L > + * > + * In case we have only one of these signals: > + * - VBUS only - we want to distinguish between [1] and [2], so ID is always 1 > + * - ID only - we want to distinguish between [1] and [4], so VBUS = ID > + */ > +static void usb_conn_detect_cable(struct work_struct *work) > +{ > + struct usb_conn_info *info; > + enum usb_role role; > + int id, vbus, ret; > + > + info = container_of(to_delayed_work(work), > + struct usb_conn_info, dw_det); > + > + /* check ID and VBUS */ > + id = info->id_gpiod ? > + gpiod_get_value_cansleep(info->id_gpiod) : 1; > + vbus = info->vbus_gpiod ? > + gpiod_get_value_cansleep(info->vbus_gpiod) : id; > + > + if (!id) > + role = USB_ROLE_HOST; > + else if (vbus) > + role = USB_ROLE_DEVICE; > + else > + role = USB_ROLE_NONE; > + > + dev_dbg(info->dev, "role %d/%d, gpios: id %d, vbus %d\n", > + info->last_role, role, id, vbus); > + > + if (info->last_role == role) { > + dev_warn(info->dev, "repeated role: %d\n", role); > + return; > + } > + > + if (info->last_role == USB_ROLE_HOST) > + regulator_disable(info->vbus); > + > + ret = usb_role_switch_set_role(info->role_sw, role); > + if (ret) > + dev_err(info->dev, "failed to set role: %d\n", ret); > + > + if (role == USB_ROLE_HOST) { > + ret = regulator_enable(info->vbus); > + if (ret) > + dev_err(info->dev, "enable vbus regulator failed\n"); > + } > + > + info->last_role = role; > + > + dev_dbg(info->dev, "vbus regulator is %s\n", > + regulator_is_enabled(info->vbus) ? "enabled" : "disabled"); > +} > + > +static void usb_conn_queue_dwork(struct usb_conn_info *info, > + unsigned long delay) > +{ > + queue_delayed_work(system_power_efficient_wq, &info->dw_det, delay); > +} > + > +static irqreturn_t usb_conn_isr(int irq, void *dev_id) > +{ > + struct usb_conn_info *info = dev_id; > + > + usb_conn_queue_dwork(info, info->debounce_jiffies); > + > + return IRQ_HANDLED; > +} > + > +static int usb_conn_probe(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct usb_conn_info *info; > + int ret = 0; > + > + info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL); > + if (!info) > + return -ENOMEM; > + > + info->dev = dev; > + info->id_gpiod = devm_gpiod_get_optional(dev, "id", GPIOD_IN); > + if (IS_ERR(info->id_gpiod)) > + return PTR_ERR(info->id_gpiod); > + > + info->vbus_gpiod = devm_gpiod_get_optional(dev, "vbus", GPIOD_IN); > + if (IS_ERR(info->vbus_gpiod)) > + return PTR_ERR(info->vbus_gpiod); > + > + if (!info->id_gpiod && !info->vbus_gpiod) { > + dev_err(dev, "failed to get gpios\n"); > + return -ENODEV; > + } > + > + if (info->id_gpiod) > + ret = gpiod_set_debounce(info->id_gpiod, USB_GPIO_DEB_US); > + if (!ret && info->vbus_gpiod) > + ret = gpiod_set_debounce(info->vbus_gpiod, USB_GPIO_DEB_US); > + if (ret < 0) > + info->debounce_jiffies = msecs_to_jiffies(USB_GPIO_DEB_MS); > + > + INIT_DELAYED_WORK(&info->dw_det, usb_conn_detect_cable); > + > + info->vbus = devm_regulator_get(dev, "vbus"); > + if (IS_ERR(info->vbus)) { > + dev_err(dev, "failed to get vbus\n"); > + return PTR_ERR(info->vbus); > + } > + > + info->role_sw = usb_role_switch_get(dev); > + if (IS_ERR(info->role_sw)) { > + if (PTR_ERR(info->role_sw) != -EPROBE_DEFER) > + dev_err(dev, "failed to get role switch\n"); > + > + return PTR_ERR(info->role_sw); > + } > + > + if (info->id_gpiod) { > + info->id_irq = gpiod_to_irq(info->id_gpiod); > + if (info->id_irq < 0) { > + dev_err(dev, "failed to get ID IRQ\n"); > + ret = info->id_irq; > + goto put_role_sw; > + } > + > + ret = devm_request_threaded_irq(dev, info->id_irq, NULL, > + usb_conn_isr, USB_CONN_IRQF, > + pdev->name, info); > + if (ret < 0) { > + dev_err(dev, "failed to request ID IRQ\n"); > + goto put_role_sw; > + } > + } > + > + if (info->vbus_gpiod) { > + info->vbus_irq = gpiod_to_irq(info->vbus_gpiod); > + if (info->vbus_irq < 0) { > + dev_err(dev, "failed to get VBUS IRQ\n"); > + ret = info->vbus_irq; > + goto put_role_sw; > + } > + > + ret = devm_request_threaded_irq(dev, info->vbus_irq, NULL, > + usb_conn_isr, USB_CONN_IRQF, > + pdev->name, info); > + if (ret < 0) { > + dev_err(dev, "failed to request VBUS IRQ\n"); > + goto put_role_sw; > + } > + } > + > + platform_set_drvdata(pdev, info); > + > + /* Perform initial detection */ > + usb_conn_queue_dwork(info, 0); > + > + return 0; > + > +put_role_sw: > + usb_role_switch_put(info->role_sw); > + return ret; > +} > + > +static int usb_conn_remove(struct platform_device *pdev) > +{ > + struct usb_conn_info *info = platform_get_drvdata(pdev); > + > + cancel_delayed_work_sync(&info->dw_det); > + > + if (info->last_role == USB_ROLE_HOST) > + regulator_disable(info->vbus); > + > + usb_role_switch_put(info->role_sw); > + > + return 0; > +} > + > +static int __maybe_unused usb_conn_suspend(struct device *dev) > +{ > + struct usb_conn_info *info = dev_get_drvdata(dev); > + > + if (info->id_gpiod) > + disable_irq(info->id_irq); > + if (info->vbus_gpiod) > + disable_irq(info->vbus_irq); > + > + pinctrl_pm_select_sleep_state(dev); > + > + return 0; > +} > + > +static int __maybe_unused usb_conn_resume(struct device *dev) > +{ > + struct usb_conn_info *info = dev_get_drvdata(dev); > + > + pinctrl_pm_select_default_state(dev); > + > + if (info->id_gpiod) > + enable_irq(info->id_irq); > + if (info->vbus_gpiod) > + enable_irq(info->vbus_irq); > + > + usb_conn_queue_dwork(info, 0); > + > + return 0; > +} > + > +static SIMPLE_DEV_PM_OPS(usb_conn_pm_ops, > + usb_conn_suspend, usb_conn_resume); > + > +static const struct of_device_id usb_conn_dt_match[] = { > + { .compatible = "linux,typeb-conn-gpio", }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, usb_conn_dt_match); > + > +static struct platform_driver usb_conn_driver = { > + .probe = usb_conn_probe, > + .remove = usb_conn_remove, > + .driver = { > + .name = "typeb-conn-gpio", > + .pm = &usb_conn_pm_ops, > + .of_match_table = usb_conn_dt_match, > + }, > +}; > + > +module_platform_driver(usb_conn_driver); > + > +MODULE_AUTHOR("Chunfeng Yun "); > +MODULE_DESCRIPTION("USB Type-B GPIO connector driver"); > +MODULE_LICENSE("GPL v2"); > -- > 2.21.0 thanks, -- heikki