Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753422AbbBST6J (ORCPT ); Thu, 19 Feb 2015 14:58:09 -0500 Received: from mga01.intel.com ([192.55.52.88]:53256 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752334AbbBST6H (ORCPT ); Thu, 19 Feb 2015 14:58:07 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.09,610,1418112000"; d="scan'208";a="688067526" From: David Cohen To: myungjoo.ham@samsung.com, cw00.choi@samsung.com Cc: linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, baolu.lu@linux.intel.com, David Cohen Subject: [PATCH v2] extcon: otg_gpio: add driver for USB OTG port controlled by GPIO(s) Date: Thu, 19 Feb 2015 11:59:44 -0800 Message-Id: <1424375984-26241-1-git-send-email-david.a.cohen@linux.intel.com> X-Mailer: git-send-email 2.1.1 In-Reply-To: <1419288217-19262-1-git-send-email-david.a.cohen@linux.intel.com> References: <1419288217-19262-1-git-send-email-david.a.cohen@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7682 Lines: 270 Some Intel platforms have an USB OTG port fully (or partially) controlled by GPIOs: (1) USB ID is connected directly to a pulled up GPIO. Optionally: (2) VBUS is enabled/disabled by a GPIO (3) Platform has 2 USB controllers connected to same port: one for device and one for host role. D+/- are switched between phys. according to this GPIO level. This driver configures USB OTG port for device or host role according to USB ID value. - If USB ID's GPIO level is low, OTG port is configured for host role by sourcing VBUS and switching D+/- to host phy. - If USB ID's GPIO level is high, by standard, the OTG port is configured for device role by not sourcing VBUS and switching D+/- to device controller. Signed-off-by: David Cohen --- Hi, Since splitting this driver into smaller pieces would result in ugly fixes WRT ACPI, I'm resending the same approach. This time I addressed all comments I got from RFC version. As always, comments are welcome. Br, David --- drivers/extcon/Kconfig | 8 ++ drivers/extcon/Makefile | 1 + drivers/extcon/extcon-otg_gpio.c | 186 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 195 insertions(+) create mode 100644 drivers/extcon/extcon-otg_gpio.c diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig index 6a1f7de6fa54..986ca7da9c1b 100644 --- a/drivers/extcon/Kconfig +++ b/drivers/extcon/Kconfig @@ -63,6 +63,14 @@ config EXTCON_MAX8997 Maxim MAX8997 PMIC. The MAX8997 MUIC is a USB port accessory detector and switch. +config EXTCON_OTG_GPIO + tristate "VIRTUAL USB OTG PORT support" + depends on GPIOLIB && ACPI + help + Say Y here to enable support for virtual USB OTG port device + controlled by GPIOs. This driver can be used when at least USB ID pin + is connected directly to GPIO. + config EXTCON_PALMAS tristate "Palmas USB EXTCON support" depends on MFD_PALMAS diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile index 0370b42e5a27..0d5b152b51ea 100644 --- a/drivers/extcon/Makefile +++ b/drivers/extcon/Makefile @@ -9,6 +9,7 @@ obj-$(CONFIG_EXTCON_GPIO) += extcon-gpio.o obj-$(CONFIG_EXTCON_MAX14577) += extcon-max14577.o obj-$(CONFIG_EXTCON_MAX77693) += extcon-max77693.o obj-$(CONFIG_EXTCON_MAX8997) += extcon-max8997.o +obj-$(CONFIG_EXTCON_OTG_GPIO) += extcon-otg_gpio.o obj-$(CONFIG_EXTCON_PALMAS) += extcon-palmas.o obj-$(CONFIG_EXTCON_RT8973A) += extcon-rt8973a.o obj-$(CONFIG_EXTCON_SM5502) += extcon-sm5502.o diff --git a/drivers/extcon/extcon-otg_gpio.c b/drivers/extcon/extcon-otg_gpio.c new file mode 100644 index 000000000000..7dfa2c15b562 --- /dev/null +++ b/drivers/extcon/extcon-otg_gpio.c @@ -0,0 +1,186 @@ +/* + * Virtual USB OTG Port driver controlled by gpios + * + * Copyright (c) 2014, Intel Corporation. + * Author: David Cohen + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include +#include +#include +#include + +#define DRV_NAME "usb_otg_port" + +struct vuport { + struct device *dev; + struct gpio_desc *gpio_vbus_en; + struct gpio_desc *gpio_usb_id; + struct gpio_desc *gpio_usb_mux; + + struct extcon_dev edev; +}; + +static const char *vuport_extcon_cable[] = { + [0] = "USB-Host", + NULL, +}; + +/* + * If id == 1, USB port should be set to peripheral + * if id == 0, USB port should be set to host + * + * Peripheral: set USB mux to peripheral and disable VBUS + * Host: set USB mux to host and enable VBUS + */ +static void vuport_set_port(struct vuport *vup, int id) +{ + int mux_val = id; + int vbus_val = !id; + + if (!IS_ERR(vup->gpio_usb_mux)) + gpiod_direction_output(vup->gpio_usb_mux, mux_val); + + if (!IS_ERR(vup->gpio_vbus_en)) + gpiod_direction_output(vup->gpio_vbus_en, vbus_val); +} + +static void vuport_do_usb_id(struct vuport *vup) +{ + int id = gpiod_get_value(vup->gpio_usb_id); + + dev_info(vup->dev, "USB PORT ID: %s\n", id ? "PERIPHERAL" : "HOST"); + + /* + * id == 1: PERIPHERAL + * id == 0: HOST + */ + vuport_set_port(vup, id); + + /* + * id == 0: HOST connected + * id == 1: Host disconnected + */ + extcon_set_cable_state(&vup->edev, "USB-Host", !id); +} + +static irqreturn_t vuport_thread_isr(int irq, void *priv) +{ + struct vuport *vup = priv; + + vuport_do_usb_id(vup); + return IRQ_HANDLED; +} + +#define VUPORT_GPIO_USB_ID 0 +#define VUPORT_GPIO_VBUS_EN 1 +#define VUPORT_GPIO_USB_MUX 2 +static int vuport_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct vuport *vup; + int ret; + + vup = devm_kzalloc(dev, sizeof(*vup), GFP_KERNEL); + if (!vup) { + dev_err(dev, "cannot allocate private data\n"); + return -ENOMEM; + } + vup->dev = dev; + + vup->gpio_usb_id = devm_gpiod_get_index(dev, "id", VUPORT_GPIO_USB_ID); + if (IS_ERR(vup->gpio_usb_id)) { + dev_err(dev, "cannot request USB ID GPIO: ret = %ld\n", + PTR_ERR(vup->gpio_usb_id)); + return PTR_ERR(vup->gpio_usb_id); + } + + ret = gpiod_direction_input(vup->gpio_usb_id); + if (ret < 0) { + dev_err(dev, "cannot set input direction to USB ID GPIO: ret = %d\n", + ret); + return ret; + } + + vup->gpio_vbus_en = devm_gpiod_get_index(dev, "vbus en", + VUPORT_GPIO_VBUS_EN); + if (IS_ERR(vup->gpio_vbus_en)) + dev_dbg(dev, "cannot request VBUS EN GPIO, skipping it.\n"); + + vup->gpio_usb_mux = devm_gpiod_get_index(dev, "usb mux", + VUPORT_GPIO_USB_MUX); + if (IS_ERR(vup->gpio_usb_mux)) + dev_dbg(dev, "cannot request USB USB MUX, skipping it.\n"); + + /* register extcon device */ + vup->edev.dev.parent = dev; + vup->edev.supported_cable = vuport_extcon_cable; + ret = extcon_dev_register(&vup->edev); + if (ret < 0) { + dev_err(dev, "failed to register extcon device: ret = %d\n", + ret); + return ret; + } + + ret = devm_request_threaded_irq(dev, gpiod_to_irq(vup->gpio_usb_id), + NULL, vuport_thread_isr, + IRQF_SHARED | IRQF_TRIGGER_RISING | + IRQF_TRIGGER_FALLING | IRQF_ONESHOT, + dev_name(dev), vup); + if (ret < 0) { + dev_err(dev, "cannot request IRQ for USB ID GPIO: ret = %d\n", + ret); + goto irq_err; + } + vuport_do_usb_id(vup); + + platform_set_drvdata(pdev, vup); + + dev_dbg(dev, "driver successfully probed\n"); + + return 0; + +irq_err: + extcon_dev_unregister(&vup->edev); + + return ret; +} + +static int vuport_remove(struct platform_device *pdev) +{ + struct vuport *vup = platform_get_drvdata(pdev); + + extcon_dev_unregister(&vup->edev); + return 0; +} + +static struct acpi_device_id vuport_acpi_match[] = { + { "INT3496" }, + { } +}; +MODULE_DEVICE_TABLE(acpi, vuport_acpi_match); + +static struct platform_driver vuport_driver = { + .driver = { + .name = DRV_NAME, + .acpi_match_table = ACPI_PTR(vuport_acpi_match), + }, + .probe = vuport_probe, + .remove = vuport_remove, +}; + +module_platform_driver(vuport_driver); + +MODULE_LICENSE("GPLv2"); +MODULE_AUTHOR("David Cohen "); -- 2.1.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/