| Message ID | 1421689942-10201-2-git-send-email-rogerq@ti.com |
|---|---|
| State | Needs Review / ACK, archived |
| Headers | show |
| Context | Check | Description |
|---|---|---|
| robh/checkpatch | warning | total: 1 errors, 0 warnings, 0 lines checked |
| robh/patch-applied | success |
On Mon, Jan 19, 2015 at 07:52:18PM +0200, Roger Quadros wrote: > 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 <rogerq@ti.com> Reviewed-by: Felipe Balbi <balbi@ti.com> Acked-by: Felipe Balbi <balbi@ti.com> > --- > .../devicetree/bindings/extcon/extcon-usb.txt | 20 ++ > drivers/extcon/Kconfig | 7 + > drivers/extcon/Makefile | 1 + > drivers/extcon/extcon-gpio-usb.c | 225 +++++++++++++++++++++ > 4 files changed, 253 insertions(+) > create mode 100644 Documentation/devicetree/bindings/extcon/extcon-usb.txt > create mode 100644 drivers/extcon/extcon-gpio-usb.c > > diff --git a/Documentation/devicetree/bindings/extcon/extcon-usb.txt b/Documentation/devicetree/bindings/extcon/extcon-usb.txt > new file mode 100644 > index 0000000..171c5a4 > --- /dev/null > +++ b/Documentation/devicetree/bindings/extcon/extcon-usb.txt > @@ -0,0 +1,20 @@ > +USB Extcon device > + > +This is a virtual device used to generate USB cable states from the USB ID pin > +connected to a GPIO pin. > + > +Required properties: > +- compatible: Should be "linux,extcon-usb" > +- id-gpio: gpio for USB ID pin. See gpio binding. > + > +Example: > + extcon_usb1 { > + compatible = "linux,extcon-usb"; > + id-gpio = <&gpio6 1 GPIO_ACTIVE_HIGH>; > + } > + > + usb@1 { > + ... > + extcon = <&extcon_usb1>; > + ... > + }; > diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig > index 6a1f7de..8106a83 100644 > --- a/drivers/extcon/Kconfig > +++ b/drivers/extcon/Kconfig > @@ -35,6 +35,13 @@ config EXTCON_GPIO > Say Y here to enable GPIO based extcon support. Note that GPIO > extcon supports single state per extcon instance. > > +config EXTCON_GPIO_USB > + tristate "USB GPIO extcon support" > + depends on GPIOLIB > + help > + Say Y here to enable GPIO based USB cable detection extcon support. > + Used typically if GPIO is used for USB ID pin detection. > + > config EXTCON_MAX14577 > tristate "MAX14577/77836 EXTCON Support" > depends on MFD_MAX14577 > diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile > index 0370b42..bae594b 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_GPIO_USB) += extcon-gpio-usb.o > diff --git a/drivers/extcon/extcon-gpio-usb.c b/drivers/extcon/extcon-gpio-usb.c > new file mode 100644 > index 0000000..aeb2298 > --- /dev/null > +++ b/drivers/extcon/extcon-gpio-usb.c > @@ -0,0 +1,225 @@ > +/** > + * drivers/extcon/extcon_gpio_usb.c - USB GPIO extcon driver > + * > + * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com > + * > + * Author: Roger Quadros <rogerq@ti.com> > + * > + * 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 <linux/extcon.h> > +#include <linux/extcon/extcon-gpio.h> > +#include <linux/gpio.h> > +#include <linux/init.h> > +#include <linux/interrupt.h> > +#include <linux/irq.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/of_gpio.h> > +#include <linux/platform_device.h> > +#include <linux/slab.h> > +#include <linux/workqueue.h> > + > +#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; > + const char **cable_names; > + > + info = container_of(to_delayed_work(work), struct usb_extcon_info, > + wq_detcable); > + cable_names = info->edev->supported_cable; > + > + /* 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, > + cable_names[EXTCON_CABLE_USB_HOST], > + false); > + extcon_set_cable_state(info->edev, > + cable_names[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, > + cable_names[EXTCON_CABLE_USB], false); > + extcon_set_cable_state(info->edev, > + cable_names[EXTCON_CABLE_USB_HOST], > + true); > + } > +} > + > +static irqreturn_t usb_irq_handler(int irq, void *dev_id) > +{ > + struct usb_extcon_info *info = dev_id; > + > + /* debounce the GPIO via delayed work */ > + 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(struct usb_extcon_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_SHARED | 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 allocate extcon device\n"); > + return ret; > + } > + > + platform_set_drvdata(pdev, info); > + /* 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; > + > + info = dev_get_drvdata(dev); > + > + if (!IS_ERR(info->id_gpiod)) > + enable_irq_wake(info->id_irq); > + > + return 0; > +} > + > +static int usb_extcon_resume(struct device *dev) > +{ > + struct usb_extcon_info *info; > + > + info = dev_get_drvdata(dev); > + > + if (!IS_ERR(info->id_gpiod)) > + disable_irq_wake(info->id_irq); > + > + return 0; > +} > +#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", }, > + { /* end */ } > +}; > + > +static struct platform_driver usb_extcon_driver = { > + .probe = usb_extcon_probe, > + .remove = usb_extcon_remove, > + .driver = { > + .name = "extcon-usb", > + .pm = &usb_extcon_pm_ops, > + .of_match_table = usb_extcon_dt_match, > + }, > +}; > + > +module_platform_driver(usb_extcon_driver); > + > +MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>"); > +MODULE_DESCRIPTION("USB GPIO extcon driver"); > +MODULE_LICENSE("GPL v2"); > -- > 2.1.0 >
Hi Roger, On 01/20/2015 02:52 AM, Roger Quadros wrote: > 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 <rogerq@ti.com> > --- > .../devicetree/bindings/extcon/extcon-usb.txt | 20 ++ > drivers/extcon/Kconfig | 7 + > drivers/extcon/Makefile | 1 + > drivers/extcon/extcon-gpio-usb.c | 225 +++++++++++++++++++++ > 4 files changed, 253 insertions(+) > create mode 100644 Documentation/devicetree/bindings/extcon/extcon-usb.txt > create mode 100644 drivers/extcon/extcon-gpio-usb.c > > diff --git a/Documentation/devicetree/bindings/extcon/extcon-usb.txt b/Documentation/devicetree/bindings/extcon/extcon-usb.txt > new file mode 100644 > index 0000000..171c5a4 > --- /dev/null > +++ b/Documentation/devicetree/bindings/extcon/extcon-usb.txt Need to rename from extcon-usb.txt to extcon-gpio-usb.txt. > @@ -0,0 +1,20 @@ > +USB Extcon device > + > +This is a virtual device used to generate USB cable states from the USB ID pin > +connected to a GPIO pin. > + > +Required properties: > +- compatible: Should be "linux,extcon-usb" I think you better use "linux,extcon-gpio-usb" because the point of this driver use the gpio for usb cable. > +- id-gpio: gpio for USB ID pin. See gpio binding. > + > +Example: > + extcon_usb1 { > + compatible = "linux,extcon-usb"; ditto. > + id-gpio = <&gpio6 1 GPIO_ACTIVE_HIGH>; > + } > + > + usb@1 { > + ... > + extcon = <&extcon_usb1>; > + ... > + }; > diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig > index 6a1f7de..8106a83 100644 > --- a/drivers/extcon/Kconfig > +++ b/drivers/extcon/Kconfig > @@ -35,6 +35,13 @@ config EXTCON_GPIO > Say Y here to enable GPIO based extcon support. Note that GPIO > extcon supports single state per extcon instance. > > +config EXTCON_GPIO_USB > + tristate "USB GPIO extcon support" > + depends on GPIOLIB > + help > + Say Y here to enable GPIO based USB cable detection extcon support. > + Used typically if GPIO is used for USB ID pin detection. > + > config EXTCON_MAX14577 > tristate "MAX14577/77836 EXTCON Support" > depends on MFD_MAX14577 > diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile > index 0370b42..bae594b 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_GPIO_USB) += extcon-gpio-usb.o Need to re-order it alphabetically. > diff --git a/drivers/extcon/extcon-gpio-usb.c b/drivers/extcon/extcon-gpio-usb.c > new file mode 100644 > index 0000000..aeb2298 > --- /dev/null > +++ b/drivers/extcon/extcon-gpio-usb.c > @@ -0,0 +1,225 @@ > +/** > + * drivers/extcon/extcon_gpio_usb.c - USB GPIO extcon driver > + * > + * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com > + * Remove un-necessary blank line. > + * Author: Roger Quadros <rogerq@ti.com> > + * > + * 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 <linux/extcon.h> > +#include <linux/extcon/extcon-gpio.h> Is it necessary? I think it is your mistake? > +#include <linux/gpio.h> Don't need it because 'of_gpio.h' includes already 'gpio.h'. > +#include <linux/init.h> > +#include <linux/interrupt.h> > +#include <linux/irq.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/of_gpio.h> > +#include <linux/platform_device.h> > +#include <linux/slab.h> > +#include <linux/workqueue.h> > + > +#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; > + const char **cable_names; > + > + info = container_of(to_delayed_work(work), struct usb_extcon_info, > + wq_detcable); > + cable_names = info->edev->supported_cable; I think you can use 'usb_extcon_cable' instead of 'cable_names'. So, you will remove 'cable_names' variable. > + > + /* 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, > + cable_names[EXTCON_CABLE_USB_HOST], > + false); > + extcon_set_cable_state(info->edev, > + cable_names[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, > + cable_names[EXTCON_CABLE_USB], false); > + extcon_set_cable_state(info->edev, > + cable_names[EXTCON_CABLE_USB_HOST], > + true); > + } > +} > + > +static irqreturn_t usb_irq_handler(int irq, void *dev_id) > +{ > + struct usb_extcon_info *info = dev_id; > + > + /* debounce the GPIO via delayed work */ I think this comment is not necessary. > + 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(struct usb_extcon_info), sizeof(struct usb_extcon_info) -> 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_SHARED | IRQF_ONESHOT, I prefer to add IRQF_NO_SUSPEND flag because IRQF_NO_SUSPEND flag is necessary for wake-up from freeze pm state. > + 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 allocate extcon device\n"); Wrong error information, you have to change verb (allocate -> register) > + return ret; > + } > + > + platform_set_drvdata(pdev, info); Need blank line. > + /* 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; > + > + info = dev_get_drvdata(dev); Simplify this code as following: struct usb_extcon_info *info = dev_get_drvdata(dev); > + > + if (!IS_ERR(info->id_gpiod)) I think that it is sufficient cheking without IS_ERR macro as following: if (info->id_gpiod) > + enable_irq_wake(info->id_irq); > + > + return 0; > +} > + > +static int usb_extcon_resume(struct device *dev) > +{ > + struct usb_extcon_info *info; > + > + info = dev_get_drvdata(dev); ditto. > + > + if (!IS_ERR(info->id_gpiod)) ditto. > + disable_irq_wake(info->id_irq); > + > + return 0; > +} > +#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", }, Change compatible name from "linux,extcon-usb", to "linux,extcon-gpio-usb". > + { /* end */ } > +}; > + > +static struct platform_driver usb_extcon_driver = { > + .probe = usb_extcon_probe, > + .remove = usb_extcon_remove, > + .driver = { > + .name = "extcon-usb", > + .pm = &usb_extcon_pm_ops, > + .of_match_table = usb_extcon_dt_match, > + }, > +}; > + > +module_platform_driver(usb_extcon_driver); > + > +MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>"); > +MODULE_DESCRIPTION("USB GPIO extcon driver"); > +MODULE_LICENSE("GPL v2"); > Thanks, Chanwoo Cho -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Chanwoo, On 21/01/15 07:28, Chanwoo Choi wrote: > Hi Roger, > > On 01/20/2015 02:52 AM, Roger Quadros wrote: >> 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 <rogerq@ti.com> >> --- >> .../devicetree/bindings/extcon/extcon-usb.txt | 20 ++ >> drivers/extcon/Kconfig | 7 + >> drivers/extcon/Makefile | 1 + >> drivers/extcon/extcon-gpio-usb.c | 225 +++++++++++++++++++++ >> 4 files changed, 253 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/extcon/extcon-usb.txt >> create mode 100644 drivers/extcon/extcon-gpio-usb.c >> >> diff --git a/Documentation/devicetree/bindings/extcon/extcon-usb.txt b/Documentation/devicetree/bindings/extcon/extcon-usb.txt >> new file mode 100644 >> index 0000000..171c5a4 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/extcon/extcon-usb.txt > > Need to rename from extcon-usb.txt to extcon-gpio-usb.txt. > >> @@ -0,0 +1,20 @@ >> +USB Extcon device >> + >> +This is a virtual device used to generate USB cable states from the USB ID pin >> +connected to a GPIO pin. >> + >> +Required properties: >> +- compatible: Should be "linux,extcon-usb" > > I think you better use "linux,extcon-gpio-usb" > because the point of this driver use the gpio for usb cable. I will change all instances of "extcon-usb" to "extcon-usb-gpio". > >> +- id-gpio: gpio for USB ID pin. See gpio binding. >> + >> +Example: >> + extcon_usb1 { >> + compatible = "linux,extcon-usb"; > > ditto. > >> + id-gpio = <&gpio6 1 GPIO_ACTIVE_HIGH>; >> + } >> + >> + usb@1 { >> + ... >> + extcon = <&extcon_usb1>; >> + ... >> + }; >> diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig >> index 6a1f7de..8106a83 100644 >> --- a/drivers/extcon/Kconfig >> +++ b/drivers/extcon/Kconfig >> @@ -35,6 +35,13 @@ config EXTCON_GPIO >> Say Y here to enable GPIO based extcon support. Note that GPIO >> extcon supports single state per extcon instance. >> >> +config EXTCON_GPIO_USB >> + tristate "USB GPIO extcon support" >> + depends on GPIOLIB >> + help >> + Say Y here to enable GPIO based USB cable detection extcon support. >> + Used typically if GPIO is used for USB ID pin detection. >> + >> config EXTCON_MAX14577 >> tristate "MAX14577/77836 EXTCON Support" >> depends on MFD_MAX14577 >> diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile >> index 0370b42..bae594b 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_GPIO_USB) += extcon-gpio-usb.o > > Need to re-order it alphabetically. OK. I will change this to extcon-usb-gpio so it will remain last. > >> diff --git a/drivers/extcon/extcon-gpio-usb.c b/drivers/extcon/extcon-gpio-usb.c >> new file mode 100644 >> index 0000000..aeb2298 >> --- /dev/null >> +++ b/drivers/extcon/extcon-gpio-usb.c >> @@ -0,0 +1,225 @@ >> +/** >> + * drivers/extcon/extcon_gpio_usb.c - USB GPIO extcon driver >> + * >> + * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com >> + * > > Remove un-necessary blank line. OK. > >> + * Author: Roger Quadros <rogerq@ti.com> >> + * >> + * 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 <linux/extcon.h> >> +#include <linux/extcon/extcon-gpio.h> > > Is it necessary? I think it is your mistake? right. my bad. > >> +#include <linux/gpio.h> > > Don't need it because 'of_gpio.h' includes already 'gpio.h'. agreed. > >> +#include <linux/init.h> >> +#include <linux/interrupt.h> >> +#include <linux/irq.h> >> +#include <linux/kernel.h> >> +#include <linux/module.h> >> +#include <linux/of_gpio.h> >> +#include <linux/platform_device.h> >> +#include <linux/slab.h> >> +#include <linux/workqueue.h> >> + >> +#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; >> + const char **cable_names; >> + >> + info = container_of(to_delayed_work(work), struct usb_extcon_info, >> + wq_detcable); >> + cable_names = info->edev->supported_cable; > > I think you can use 'usb_extcon_cable' instead of 'cable_names'. > So, you will remove 'cable_names' variable. > OK. >> + >> + /* 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, >> + cable_names[EXTCON_CABLE_USB_HOST], >> + false); >> + extcon_set_cable_state(info->edev, >> + cable_names[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, >> + cable_names[EXTCON_CABLE_USB], false); >> + extcon_set_cable_state(info->edev, >> + cable_names[EXTCON_CABLE_USB_HOST], >> + true); >> + } >> +} >> + >> +static irqreturn_t usb_irq_handler(int irq, void *dev_id) >> +{ >> + struct usb_extcon_info *info = dev_id; >> + >> + /* debounce the GPIO via delayed work */ > > I think this comment is not necessary. OK. > >> + 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(struct usb_extcon_info), > > sizeof(struct usb_extcon_info) -> sizeof(*info) > right. >> + 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_SHARED | IRQF_ONESHOT, > > I prefer to add IRQF_NO_SUSPEND flag because IRQF_NO_SUSPEND flag is necessary > for wake-up from freeze pm state. Agreed. > >> + 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 allocate extcon device\n"); > > Wrong error information, you have to change verb (allocate -> register) will fix. > >> + return ret; >> + } >> + >> + platform_set_drvdata(pdev, info); > > Need blank line. OK. > >> + /* 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; >> + >> + info = dev_get_drvdata(dev); > > Simplify this code as following: > struct usb_extcon_info *info = dev_get_drvdata(dev); OK. > >> + >> + if (!IS_ERR(info->id_gpiod)) > > I think that it is sufficient cheking without IS_ERR macro as following: > if (info->id_gpiod) I will remove this if check as we're failing probe if id_gpiod is not valid. > >> + enable_irq_wake(info->id_irq); >> + >> + return 0; >> +} >> + >> +static int usb_extcon_resume(struct device *dev) >> +{ >> + struct usb_extcon_info *info; >> + >> + info = dev_get_drvdata(dev); > > ditto. > >> + >> + if (!IS_ERR(info->id_gpiod)) > > ditto. > >> + disable_irq_wake(info->id_irq); >> + >> + return 0; >> +} >> +#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", }, > > Change compatible name from "linux,extcon-usb", to "linux,extcon-gpio-usb". > will use "linux,extcon-usb-gpio" >> + { /* end */ } >> +}; >> + >> +static struct platform_driver usb_extcon_driver = { >> + .probe = usb_extcon_probe, >> + .remove = usb_extcon_remove, >> + .driver = { >> + .name = "extcon-usb", >> + .pm = &usb_extcon_pm_ops, >> + .of_match_table = usb_extcon_dt_match, >> + }, >> +}; >> + >> +module_platform_driver(usb_extcon_driver); >> + >> +MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>"); >> +MODULE_DESCRIPTION("USB GPIO extcon driver"); >> +MODULE_LICENSE("GPL v2"); >> cheers, -roger -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/devicetree/bindings/extcon/extcon-usb.txt b/Documentation/devicetree/bindings/extcon/extcon-usb.txt new file mode 100644 index 0000000..171c5a4 --- /dev/null +++ b/Documentation/devicetree/bindings/extcon/extcon-usb.txt @@ -0,0 +1,20 @@ +USB Extcon device + +This is a virtual device used to generate USB cable states from the USB ID pin +connected to a GPIO pin. + +Required properties: +- compatible: Should be "linux,extcon-usb" +- id-gpio: gpio for USB ID pin. See gpio binding. + +Example: + extcon_usb1 { + compatible = "linux,extcon-usb"; + id-gpio = <&gpio6 1 GPIO_ACTIVE_HIGH>; + } + + usb@1 { + ... + extcon = <&extcon_usb1>; + ... + }; diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig index 6a1f7de..8106a83 100644 --- a/drivers/extcon/Kconfig +++ b/drivers/extcon/Kconfig @@ -35,6 +35,13 @@ config EXTCON_GPIO Say Y here to enable GPIO based extcon support. Note that GPIO extcon supports single state per extcon instance. +config EXTCON_GPIO_USB + tristate "USB GPIO extcon support" + depends on GPIOLIB + help + Say Y here to enable GPIO based USB cable detection extcon support. + Used typically if GPIO is used for USB ID pin detection. + config EXTCON_MAX14577 tristate "MAX14577/77836 EXTCON Support" depends on MFD_MAX14577 diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile index 0370b42..bae594b 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_GPIO_USB) += extcon-gpio-usb.o diff --git a/drivers/extcon/extcon-gpio-usb.c b/drivers/extcon/extcon-gpio-usb.c new file mode 100644 index 0000000..aeb2298 --- /dev/null +++ b/drivers/extcon/extcon-gpio-usb.c @@ -0,0 +1,225 @@ +/** + * drivers/extcon/extcon_gpio_usb.c - USB GPIO extcon driver + * + * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com + * + * Author: Roger Quadros <rogerq@ti.com> + * + * 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 <linux/extcon.h> +#include <linux/extcon/extcon-gpio.h> +#include <linux/gpio.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_gpio.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/workqueue.h> + +#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; + const char **cable_names; + + info = container_of(to_delayed_work(work), struct usb_extcon_info, + wq_detcable); + cable_names = info->edev->supported_cable; + + /* 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, + cable_names[EXTCON_CABLE_USB_HOST], + false); + extcon_set_cable_state(info->edev, + cable_names[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, + cable_names[EXTCON_CABLE_USB], false); + extcon_set_cable_state(info->edev, + cable_names[EXTCON_CABLE_USB_HOST], + true); + } +} + +static irqreturn_t usb_irq_handler(int irq, void *dev_id) +{ + struct usb_extcon_info *info = dev_id; + + /* debounce the GPIO via delayed work */ + 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(struct usb_extcon_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_SHARED | 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 allocate extcon device\n"); + return ret; + } + + platform_set_drvdata(pdev, info); + /* 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; + + info = dev_get_drvdata(dev); + + if (!IS_ERR(info->id_gpiod)) + enable_irq_wake(info->id_irq); + + return 0; +} + +static int usb_extcon_resume(struct device *dev) +{ + struct usb_extcon_info *info; + + info = dev_get_drvdata(dev); + + if (!IS_ERR(info->id_gpiod)) + disable_irq_wake(info->id_irq); + + return 0; +} +#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", }, + { /* end */ } +}; + +static struct platform_driver usb_extcon_driver = { + .probe = usb_extcon_probe, + .remove = usb_extcon_remove, + .driver = { + .name = "extcon-usb", + .pm = &usb_extcon_pm_ops, + .of_match_table = usb_extcon_dt_match, + }, +}; + +module_platform_driver(usb_extcon_driver); + +MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>"); +MODULE_DESCRIPTION("USB GPIO extcon driver"); +MODULE_LICENSE("GPL v2");
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 <rogerq@ti.com> --- .../devicetree/bindings/extcon/extcon-usb.txt | 20 ++ drivers/extcon/Kconfig | 7 + drivers/extcon/Makefile | 1 + drivers/extcon/extcon-gpio-usb.c | 225 +++++++++++++++++++++ 4 files changed, 253 insertions(+) create mode 100644 Documentation/devicetree/bindings/extcon/extcon-usb.txt create mode 100644 drivers/extcon/extcon-gpio-usb.c