Hi Robert, This looks like a extcon driver based on gpio for USB.
Roger posted a generic one a while back. https://lkml.org/lkml/2015/2/2/187 Doesn't this serve the purpose rather than adding this driver? -George On Wed, Mar 18, 2015 at 7:34 PM, Robert Baldyga <r.bald...@samsung.com> wrote: > This patch adds extcon driver for Odroid U3, U3+ and X boards. > It recognizes type of USB cable connected to Odroid board basing on > two signal lines VBUS_DET and OTG_ID (the second one is present only > on Odroid U3+ board). > > Following table of states presents relationship between this signals > and detected cable type: > > state | VBUS_DET | OTG_ID > ------------------------------- > USB | H | H > USB_HOST | H | L > disconn. | L | H > USB-HOST | L | L > > This driver is based on extcon-gpio driver. > > Signed-off-by: Łukasz Stelmach <l.stelm...@samsung.com> > Signed-off-by: Robert Baldyga <r.bald...@samsung.com> > --- > drivers/extcon/Kconfig | 4 + > drivers/extcon/Makefile | 1 + > drivers/extcon/extcon-odroid-usbotg.c | 256 > ++++++++++++++++++++++++++++++++++ > 3 files changed, 261 insertions(+) > create mode 100644 drivers/extcon/extcon-odroid-usbotg.c > > diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig > index 6a1f7de..891dca3 100644 > --- a/drivers/extcon/Kconfig > +++ b/drivers/extcon/Kconfig > @@ -93,4 +93,8 @@ config EXTCON_SM5502 > Silicon Mitus SM5502. The SM5502 is a USB port accessory > detector and switch. > > +config EXTCON_ODROID_USBOTG > + tristate "Extcon Odroid U3, U3+, X and XU USB OTG port" > + depends on OF_GPIO > + > endif # MULTISTATE_SWITCH > diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile > index 0370b42..514384e 100644 > --- a/drivers/extcon/Makefile > +++ b/drivers/extcon/Makefile > @@ -12,3 +12,4 @@ obj-$(CONFIG_EXTCON_MAX8997) += extcon-max8997.o > obj-$(CONFIG_EXTCON_PALMAS) += extcon-palmas.o > obj-$(CONFIG_EXTCON_RT8973A) += extcon-rt8973a.o > obj-$(CONFIG_EXTCON_SM5502) += extcon-sm5502.o > +obj-$(CONFIG_EXTCON_ODROID_USBOTG) += extcon-odroid-usbotg.o > diff --git a/drivers/extcon/extcon-odroid-usbotg.c > b/drivers/extcon/extcon-odroid-usbotg.c > new file mode 100644 > index 0000000..7f71c48 > --- /dev/null > +++ b/drivers/extcon/extcon-odroid-usbotg.c > @@ -0,0 +1,256 @@ > +/* > + * drivers/extcon/extcon-odroid-usbotg.c > + * > + * USB cable extcon driver for Odroid U3, Odroid U3+ and Odroid X > + * > + * Copyright (C) 2014 Samsung Electronics > + * Author: Lukasz Stelmach <l.stelm...@samsung.com> > + * Author: Robert Baldyga <r.bald...@samsung.com> > + * > + * based on drivers/extcon/extcon-gpio.c > + * Copyright (C) 2008 Google, Inc. > + * Author: Mike Lockwood <lockw...@android.com> > + * > + * This software is licensed under the terms of the GNU General Public > + * License version 2, as published by the Free Software Foundation, and > + * may be copied, distributed, and modified under those terms. > + * > + * 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 <linux/module.h> > +#include <linux/kernel.h> > +#include <linux/init.h> > +#include <linux/interrupt.h> > +#include <linux/platform_device.h> > +#include <linux/slab.h> > +#include <linux/gpio.h> > +#include <linux/of_gpio.h> > +#include <linux/extcon.h> > +#include <linux/extcon/extcon-gpio.h> > +#include <linux/delay.h> > + > +enum { > + EXTCON_CABLE_USB = 0, > + EXTCON_CABLE_USB_HOST, > + > + _EXTCON_CABLE_NUM, > +}; > + > +static const char * const odroid_usbotg_cable[] = { > + [EXTCON_CABLE_USB] = "USB", > + [EXTCON_CABLE_USB_HOST] = "USB-HOST", > + > + NULL, > +}; > + > +struct odroid_usbotg_data { > + struct extcon_dev *edev; > + struct gpio_desc *otg_id; > + struct gpio_desc *vbus_det; > + int otg_id_irq; > + int vbus_det_irq; > + unsigned long debounce_ms; > +}; > + > +/* > + * state | VBUS_DET | OTG_ID > + * ------------------------------- > + * USB | H | H > + * USB-HOST | H | L > + * disconn. | L | H > + * USB-HOST | L | L > + * > + * Only Odroid U3+ has OTG_ID line. U3 and X versions can detect only > + * USB slave cable. > + */ > + > +static void odroid_usbotg_detect_cable(struct odroid_usbotg_data > *extcon_data) > +{ > + int state; > + > + mdelay(extcon_data->debounce_ms); > + > + if (extcon_data->otg_id) > + state = (gpiod_get_value(extcon_data->vbus_det) << 1) | > + gpiod_get_value(extcon_data->otg_id); > + else > + state = (gpiod_get_value(extcon_data->vbus_det) << 1) | 1; > + > + dev_dbg(&extcon_data->edev->dev, "cable state changed to %d\n", > state); > + > + if (state & 0x1) > + extcon_set_cable_state_(extcon_data->edev, > + EXTCON_CABLE_USB_HOST, false); > + if (state != 0x3) > + extcon_set_cable_state_(extcon_data->edev, > + EXTCON_CABLE_USB, false); > + > + if (!(state & 0x1)) > + extcon_set_cable_state_(extcon_data->edev, > + EXTCON_CABLE_USB_HOST, true); > + else if (state == 0x3) > + extcon_set_cable_state_(extcon_data->edev, > + EXTCON_CABLE_USB, true); > +} > + > +static irqreturn_t gpio_irq_handler(int irq, void *dev_id) > +{ > + struct odroid_usbotg_data *extcon_data = dev_id; > + > + odroid_usbotg_detect_cable(extcon_data); > + > + return IRQ_HANDLED; > +} > + > +static int odroid_usbotg_parse_dt(struct platform_device *pdev, > + struct odroid_usbotg_data *extcon_data) > +{ > + struct device_node *np = pdev->dev.of_node; > + u32 val; > + > + if (!np) > + return -ENODEV; > + > + extcon_data->edev->name = np->name; > + > + if (of_property_read_u32(np, "debounce", &val) != 0) > + val = 50; > + extcon_data->debounce_ms = val; > + > + return 0; > +} > + > +static int odroid_usbotg_probe(struct platform_device *pdev) > +{ > + struct odroid_usbotg_data *extcon_data; > + int ret = 0; > + > + extcon_data = devm_kzalloc(&pdev->dev, > + sizeof(struct odroid_usbotg_data), GFP_KERNEL); > + if (!extcon_data) > + return -ENOMEM; > + > + extcon_data->edev = devm_kzalloc(&pdev->dev, sizeof(struct > extcon_dev), > + GFP_KERNEL); > + if (IS_ERR(extcon_data->edev)) { > + dev_err(&pdev->dev, "failed to allocate extcon device\n"); > + return -ENOMEM; > + } > + extcon_data->edev->supported_cable = odroid_usbotg_cable; > + > + ret = odroid_usbotg_parse_dt(pdev, extcon_data); > + if (IS_ERR_VALUE(ret)) { > + dev_err(&pdev->dev, "failed to get data from device tree\n"); > + return ret; > + } > + > + /* gpios */ > + extcon_data->vbus_det = devm_gpiod_get(&pdev->dev, "vbus-det"); > + if (IS_ERR(extcon_data->vbus_det)) { > + dev_err(&pdev->dev, "failed to get vbus_det gpio\n"); > + return PTR_ERR(extcon_data->vbus_det); > + } > + extcon_data->otg_id = devm_gpiod_get_optional(&pdev->dev, "otg-id"); > + > + extcon_data->edev->dev.parent = &pdev->dev; > + ret = extcon_dev_register(extcon_data->edev); > + if (ret < 0) > + return ret; > + > + /* irq */ > + extcon_data->vbus_det_irq = gpiod_to_irq(extcon_data->vbus_det); > + if (extcon_data->vbus_det_irq < 0) { > + dev_err(&pdev->dev, "failed to get irq from vbus_det\n"); > + ret = extcon_data->vbus_det_irq; > + goto err; > + } > + ret = request_threaded_irq(extcon_data->vbus_det_irq, NULL, > + gpio_irq_handler, IRQF_ONESHOT | > + IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, > + pdev->name, extcon_data); > + if (ret < 0) { > + dev_err(&pdev->dev, "failed to request vbus_det irq\n"); > + goto err; > + } > + > + if (extcon_data->otg_id) { > + extcon_data->otg_id_irq = gpiod_to_irq(extcon_data->otg_id); > + if (extcon_data->otg_id_irq < 0) { > + dev_err(&pdev->dev, "failed to get irq from > otg_id\n"); > + ret = extcon_data->otg_id_irq; > + goto err; > + } > + ret = request_threaded_irq(extcon_data->otg_id_irq, NULL, > + gpio_irq_handler, IRQF_ONESHOT | > + IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, > + pdev->name, extcon_data); > + if (ret < 0) { > + dev_err(&pdev->dev, "failed to request otg_id irq\n"); > + goto err; > + } > + } > + > + platform_set_drvdata(pdev, extcon_data); > + /* Perform initial detection */ > + odroid_usbotg_detect_cable(extcon_data); > + > + dev_dbg(&pdev->dev, "probe: success\n"); > + > + return 0; > + > +err: > + extcon_dev_unregister(extcon_data->edev); > + > + return ret; > +} > + > +static int odroid_usbotg_remove(struct platform_device *pdev) > +{ > + struct odroid_usbotg_data *extcon_data = platform_get_drvdata(pdev); > + > + free_irq(extcon_data->vbus_det_irq, extcon_data); > + if (extcon_data->otg_id) > + free_irq(extcon_data->otg_id_irq, extcon_data); > + extcon_dev_unregister(extcon_data->edev); > + > + return 0; > +} > + > +static const struct of_device_id odroid_usbotg_of_match[] = { > + { .compatible = "extcon-odroid-usbotg" }, > + { }, > +}; > +MODULE_DEVICE_TABLE(of, odroid_usbotg_of_match); > + > +static struct platform_driver odroid_usbotg_driver = { > + .probe = odroid_usbotg_probe, > + .remove = odroid_usbotg_remove, > + .driver = { > + .name = "odroid-usbotg", > + .owner = THIS_MODULE, > + .of_match_table = of_match_ptr(odroid_usbotg_of_match) > + }, > +}; > + > +static int __init odroid_usbotg_init(void) > +{ > + return platform_driver_register(&odroid_usbotg_driver); > +} > + > +subsys_initcall(odroid_usbotg_init); > + > +static void __exit odroid_usbotg_cleanup(void) > +{ > + platform_driver_unregister(&odroid_usbotg_driver); > +} > + > +module_exit(odroid_usbotg_cleanup); > + > +MODULE_AUTHOR("Lukasz Stelmach <l.stelm...@samsung.com>, Robert Baldyga > <r.bald...@samsung.com>"); > +MODULE_DESCRIPTION("USB OTG extcon driver for Odroid U3, U3+ and X"); > +MODULE_LICENSE("GPL"); > -- > 1.9.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-usb" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
