From e52817faae359ce95c93c2b6eb88b16d4b430181 Mon Sep 17 00:00:00 2001 From: Roger Quadros Date: Mon, 2 Feb 2015 12:21:59 +0200 Subject: extcon: usb-gpio: Introduce gpio usb extcon driver This driver observes the USB ID pin connected over a GPIO and updates the USB cable extcon states accordingly. The existing GPIO extcon driver is not suitable for this purpose as it needs to be taught to understand USB cable states and it can't handle more than one cable per instance. For the USB case we need to handle 2 cable states. 1) USB (attach/detach) 2) USB-HOST (attach/detach) This driver can be easily updated in the future to handle VBUS events in case it happens to be available on GPIO for any platform. Signed-off-by: Roger Quadros Reviewed-by: Felipe Balbi Acked-by: Felipe Balbi Signed-off-by: Chanwoo Choi --- drivers/extcon/extcon-usb-gpio.c | 237 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 237 insertions(+) create mode 100644 drivers/extcon/extcon-usb-gpio.c (limited to 'drivers/extcon/extcon-usb-gpio.c') diff --git a/drivers/extcon/extcon-usb-gpio.c b/drivers/extcon/extcon-usb-gpio.c new file mode 100644 index 000000000000..3f0bad3ce8aa --- /dev/null +++ b/drivers/extcon/extcon-usb-gpio.c @@ -0,0 +1,237 @@ +/** + * drivers/extcon/extcon-usb-gpio.c - USB GPIO extcon driver + * + * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com + * Author: Roger Quadros + * + * 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 +#include +#include +#include +#include + +#define USB_GPIO_DEBOUNCE_MS 20 /* ms */ + +struct usb_extcon_info { + struct device *dev; + struct extcon_dev *edev; + + struct gpio_desc *id_gpiod; + int id_irq; + + unsigned long debounce_jiffies; + struct delayed_work wq_detcable; +}; + +/* List of detectable cables */ +enum { + EXTCON_CABLE_USB = 0, + EXTCON_CABLE_USB_HOST, + + EXTCON_CABLE_END, +}; + +static const char *usb_extcon_cable[] = { + [EXTCON_CABLE_USB] = "USB", + [EXTCON_CABLE_USB_HOST] = "USB-HOST", + NULL, +}; + +static void usb_extcon_detect_cable(struct work_struct *work) +{ + int id; + struct usb_extcon_info *info = container_of(to_delayed_work(work), + struct usb_extcon_info, + wq_detcable); + + /* check ID and update cable state */ + id = gpiod_get_value_cansleep(info->id_gpiod); + if (id) { + /* + * ID = 1 means USB HOST cable detached. + * As we don't have event for USB peripheral cable attached, + * we simulate USB peripheral attach here. + */ + extcon_set_cable_state(info->edev, + usb_extcon_cable[EXTCON_CABLE_USB_HOST], + false); + extcon_set_cable_state(info->edev, + usb_extcon_cable[EXTCON_CABLE_USB], + true); + } else { + /* + * ID = 0 means USB HOST cable attached. + * As we don't have event for USB peripheral cable detached, + * we simulate USB peripheral detach here. + */ + extcon_set_cable_state(info->edev, + usb_extcon_cable[EXTCON_CABLE_USB], + false); + extcon_set_cable_state(info->edev, + usb_extcon_cable[EXTCON_CABLE_USB_HOST], + true); + } +} + +static irqreturn_t usb_irq_handler(int irq, void *dev_id) +{ + struct usb_extcon_info *info = dev_id; + + queue_delayed_work(system_power_efficient_wq, &info->wq_detcable, + info->debounce_jiffies); + + return IRQ_HANDLED; +} + +static int usb_extcon_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct usb_extcon_info *info; + int ret; + + if (!np) + return -EINVAL; + + info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL); + if (!info) + return -ENOMEM; + + info->dev = dev; + info->id_gpiod = devm_gpiod_get(&pdev->dev, "id"); + if (IS_ERR(info->id_gpiod)) { + dev_err(dev, "failed to get ID GPIO\n"); + return PTR_ERR(info->id_gpiod); + } + + ret = gpiod_set_debounce(info->id_gpiod, + USB_GPIO_DEBOUNCE_MS * 1000); + if (ret < 0) + info->debounce_jiffies = msecs_to_jiffies(USB_GPIO_DEBOUNCE_MS); + + INIT_DELAYED_WORK(&info->wq_detcable, usb_extcon_detect_cable); + + info->id_irq = gpiod_to_irq(info->id_gpiod); + if (info->id_irq < 0) { + dev_err(dev, "failed to get ID IRQ\n"); + return info->id_irq; + } + + ret = devm_request_threaded_irq(dev, info->id_irq, NULL, + usb_irq_handler, + IRQF_TRIGGER_RISING | + IRQF_TRIGGER_FALLING | IRQF_ONESHOT, + pdev->name, info); + if (ret < 0) { + dev_err(dev, "failed to request handler for ID IRQ\n"); + return ret; + } + + info->edev = devm_extcon_dev_allocate(dev, usb_extcon_cable); + if (IS_ERR(info->edev)) { + dev_err(dev, "failed to allocate extcon device\n"); + return -ENOMEM; + } + + ret = devm_extcon_dev_register(dev, info->edev); + if (ret < 0) { + dev_err(dev, "failed to register extcon device\n"); + return ret; + } + + platform_set_drvdata(pdev, info); + device_init_wakeup(dev, 1); + + /* Perform initial detection */ + usb_extcon_detect_cable(&info->wq_detcable.work); + + return 0; +} + +static int usb_extcon_remove(struct platform_device *pdev) +{ + struct usb_extcon_info *info = platform_get_drvdata(pdev); + + cancel_delayed_work_sync(&info->wq_detcable); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int usb_extcon_suspend(struct device *dev) +{ + struct usb_extcon_info *info = dev_get_drvdata(dev); + int ret = 0; + + if (device_may_wakeup(dev)) { + ret = enable_irq_wake(info->id_irq); + if (ret) + return ret; + } + + /* + * We don't want to process any IRQs after this point + * as GPIOs used behind I2C subsystem might not be + * accessible until resume completes. So disable IRQ. + */ + disable_irq(info->id_irq); + + return ret; +} + +static int usb_extcon_resume(struct device *dev) +{ + struct usb_extcon_info *info = dev_get_drvdata(dev); + int ret = 0; + + if (device_may_wakeup(dev)) { + ret = disable_irq_wake(info->id_irq); + if (ret) + return ret; + } + + enable_irq(info->id_irq); + + return ret; +} +#endif + +static SIMPLE_DEV_PM_OPS(usb_extcon_pm_ops, + usb_extcon_suspend, usb_extcon_resume); + +static struct of_device_id usb_extcon_dt_match[] = { + { .compatible = "linux,extcon-usb-gpio", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, usb_extcon_dt_match); + +static struct platform_driver usb_extcon_driver = { + .probe = usb_extcon_probe, + .remove = usb_extcon_remove, + .driver = { + .name = "extcon-usb-gpio", + .pm = &usb_extcon_pm_ops, + .of_match_table = usb_extcon_dt_match, + }, +}; + +module_platform_driver(usb_extcon_driver); + +MODULE_AUTHOR("Roger Quadros "); +MODULE_DESCRIPTION("USB GPIO extcon driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3 From 34825e511971e193db16a96350faeb60eff0d842 Mon Sep 17 00:00:00 2001 From: Chanwoo Choi Date: Sat, 7 Mar 2015 01:41:36 +0900 Subject: extcon: Fix the checkpatch warning This patch fixes the checkpatch warning about coding style. Signed-off-by: Chanwoo Choi --- drivers/extcon/extcon-max14577.c | 5 +---- drivers/extcon/extcon-max77693.c | 5 +---- drivers/extcon/extcon-max8997.c | 5 +---- drivers/extcon/extcon-rt8973a.c | 6 ++---- drivers/extcon/extcon-sm5502.c | 6 +++--- drivers/extcon/extcon-usb-gpio.c | 2 +- drivers/extcon/extcon.c | 1 + 7 files changed, 10 insertions(+), 20 deletions(-) (limited to 'drivers/extcon/extcon-usb-gpio.c') diff --git a/drivers/extcon/extcon-max14577.c b/drivers/extcon/extcon-max14577.c index c1bf0cf747b0..3823aa4a3a80 100644 --- a/drivers/extcon/extcon-max14577.c +++ b/drivers/extcon/extcon-max14577.c @@ -539,8 +539,6 @@ static void max14577_muic_irq_work(struct work_struct *work) dev_err(info->dev, "failed to handle MUIC interrupt\n"); mutex_unlock(&info->mutex); - - return; } /* @@ -730,8 +728,7 @@ static int max14577_muic_probe(struct platform_device *pdev) muic_irq->name, info); if (ret) { dev_err(&pdev->dev, - "failed: irq request (IRQ: %d," - " error :%d)\n", + "failed: irq request (IRQ: %d, error :%d)\n", muic_irq->irq, ret); return ret; } diff --git a/drivers/extcon/extcon-max77693.c b/drivers/extcon/extcon-max77693.c index dfcc5cba25f0..a66bec8f6252 100644 --- a/drivers/extcon/extcon-max77693.c +++ b/drivers/extcon/extcon-max77693.c @@ -1019,8 +1019,6 @@ static void max77693_muic_irq_work(struct work_struct *work) dev_err(info->dev, "failed to handle MUIC interrupt\n"); mutex_unlock(&info->mutex); - - return; } static irqreturn_t max77693_muic_irq_handler(int irq, void *data) @@ -1171,8 +1169,7 @@ static int max77693_muic_probe(struct platform_device *pdev) muic_irq->name, info); if (ret) { dev_err(&pdev->dev, - "failed: irq request (IRQ: %d," - " error :%d)\n", + "failed: irq request (IRQ: %d, error :%d)\n", muic_irq->irq, ret); return ret; } diff --git a/drivers/extcon/extcon-max8997.c b/drivers/extcon/extcon-max8997.c index fc1678fa95c4..5774e56c6422 100644 --- a/drivers/extcon/extcon-max8997.c +++ b/drivers/extcon/extcon-max8997.c @@ -579,8 +579,6 @@ static void max8997_muic_irq_work(struct work_struct *work) dev_err(info->dev, "failed to handle MUIC interrupt\n"); mutex_unlock(&info->mutex); - - return; } static irqreturn_t max8997_muic_irq_handler(int irq, void *data) @@ -689,8 +687,7 @@ static int max8997_muic_probe(struct platform_device *pdev) muic_irq->name, info); if (ret) { dev_err(&pdev->dev, - "failed: irq request (IRQ: %d," - " error :%d)\n", + "failed: irq request (IRQ: %d, error :%d)\n", muic_irq->irq, ret); goto err_irq; } diff --git a/drivers/extcon/extcon-rt8973a.c b/drivers/extcon/extcon-rt8973a.c index a784b2d5ee72..9ccd5af89d1c 100644 --- a/drivers/extcon/extcon-rt8973a.c +++ b/drivers/extcon/extcon-rt8973a.c @@ -582,10 +582,8 @@ static int rt8973a_muic_i2c_probe(struct i2c_client *i2c, return -EINVAL; info = devm_kzalloc(&i2c->dev, sizeof(*info), GFP_KERNEL); - if (!info) { - dev_err(&i2c->dev, "failed to allocate memory\n"); + if (!info) return -ENOMEM; - } i2c_set_clientdata(i2c, info); info->dev = &i2c->dev; @@ -681,7 +679,7 @@ static int rt8973a_muic_i2c_remove(struct i2c_client *i2c) return 0; } -static struct of_device_id rt8973a_dt_match[] = { +static const struct of_device_id rt8973a_dt_match[] = { { .compatible = "richtek,rt8973a-muic" }, { }, }; diff --git a/drivers/extcon/extcon-sm5502.c b/drivers/extcon/extcon-sm5502.c index b0f7bd82af90..2f93cf307852 100644 --- a/drivers/extcon/extcon-sm5502.c +++ b/drivers/extcon/extcon-sm5502.c @@ -359,8 +359,8 @@ static unsigned int sm5502_muic_get_cable_type(struct sm5502_muic_info *info) break; default: dev_dbg(info->dev, - "cannot identify the cable type: adc(0x%x) " - "dev_type1(0x%x)\n", adc, dev_type1); + "cannot identify the cable type: adc(0x%x)\n", + adc); return -EINVAL; }; break; @@ -659,7 +659,7 @@ static int sm5502_muic_i2c_remove(struct i2c_client *i2c) return 0; } -static struct of_device_id sm5502_dt_match[] = { +static const struct of_device_id sm5502_dt_match[] = { { .compatible = "siliconmitus,sm5502-muic" }, { }, }; diff --git a/drivers/extcon/extcon-usb-gpio.c b/drivers/extcon/extcon-usb-gpio.c index 3f0bad3ce8aa..de67fce18984 100644 --- a/drivers/extcon/extcon-usb-gpio.c +++ b/drivers/extcon/extcon-usb-gpio.c @@ -214,7 +214,7 @@ static int usb_extcon_resume(struct device *dev) static SIMPLE_DEV_PM_OPS(usb_extcon_pm_ops, usb_extcon_suspend, usb_extcon_resume); -static struct of_device_id usb_extcon_dt_match[] = { +static const struct of_device_id usb_extcon_dt_match[] = { { .compatible = "linux,extcon-usb-gpio", }, { /* sentinel */ } }; diff --git a/drivers/extcon/extcon.c b/drivers/extcon/extcon.c index 8319f25b7145..752ce1208428 100644 --- a/drivers/extcon/extcon.c +++ b/drivers/extcon/extcon.c @@ -158,6 +158,7 @@ static ssize_t name_show(struct device *dev, struct device_attribute *attr, /* Optional callback given by the user */ if (edev->print_name) { int ret = edev->print_name(edev, buf); + if (ret >= 0) return ret; } -- cgit v1.2.3 From bc1aabad39f42fa293f2a944fd9327bba27b59cd Mon Sep 17 00:00:00 2001 From: Robert Baldyga Date: Thu, 2 Apr 2015 15:13:02 +0200 Subject: extcon: usb-gpio: register extcon device before IRQ registration IRQ handler touches info->edev, so if interrupt occurs before extcon device initialization it can cause NULL pointer dereference. Doing extcon initialization before IRQ handler registration fixes this problem. Signed-off-by: Robert Baldyga Acked-by: Roger Quadros Signed-off-by: Chanwoo Choi --- drivers/extcon/extcon-usb-gpio.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) (limited to 'drivers/extcon/extcon-usb-gpio.c') diff --git a/drivers/extcon/extcon-usb-gpio.c b/drivers/extcon/extcon-usb-gpio.c index de67fce18984..e45d1f13f445 100644 --- a/drivers/extcon/extcon-usb-gpio.c +++ b/drivers/extcon/extcon-usb-gpio.c @@ -119,6 +119,18 @@ static int usb_extcon_probe(struct platform_device *pdev) return PTR_ERR(info->id_gpiod); } + info->edev = devm_extcon_dev_allocate(dev, usb_extcon_cable); + if (IS_ERR(info->edev)) { + dev_err(dev, "failed to allocate extcon device\n"); + return -ENOMEM; + } + + ret = devm_extcon_dev_register(dev, info->edev); + if (ret < 0) { + dev_err(dev, "failed to register extcon device\n"); + return ret; + } + ret = gpiod_set_debounce(info->id_gpiod, USB_GPIO_DEBOUNCE_MS * 1000); if (ret < 0) @@ -142,18 +154,6 @@ static int usb_extcon_probe(struct platform_device *pdev) return ret; } - info->edev = devm_extcon_dev_allocate(dev, usb_extcon_cable); - if (IS_ERR(info->edev)) { - dev_err(dev, "failed to allocate extcon device\n"); - return -ENOMEM; - } - - ret = devm_extcon_dev_register(dev, info->edev); - if (ret < 0) { - dev_err(dev, "failed to register extcon device\n"); - return ret; - } - platform_set_drvdata(pdev, info); device_init_wakeup(dev, 1); -- cgit v1.2.3