Hi Sergei, On 2015년 12월 12일 08:22, Sergei Shtylyov wrote: > Maxim Integrated MAX3355E chip integrates a charge pump and comparators to ^^ ^^ > enable a system with an integrated USB OTG dual-role transceiver to function > as an USB OTG dual-role device. In addition to sensing/controlling Vbus, ^^ ^^ ^^ ^^ > the chip also passes thru the ID signal from the USB OTG connector. ^^ > On some Renesas boards, this signal is just fed into the SoC thru a GPIO ^^ ^^ > pin -- there's no real OTG controller, only host and gadget USB controllers ^^ ^^ > sharing the same USB bus; however, we'd like to allow host or gadget drivers ^^ > to be loaded depending on the cable type, hence the need for the MAX3355 ^^ > extcon driver. The Vbus status signals are also wired to GPIOs (however, we > aren't currently interested in them), the OFFVBUS# signal is controlled by ^^ ^^ > the host controllers, there's also the SHDN# signal wired to a GPIO, it ^^ > should be driven high for the normal operation. ^^ As above '^' expression, you used the double space between words. You should fix it. Thanks, Chanwoo Choi > > Signed-off-by: Sergei Shtylyov <sergei.shtylyov@xxxxxxxxxxxxxxxxxx> > > --- > The patch is against the 'extcon-next' branch of the 'extcon.git' repo. > > Changes in version 2: > - added the USB gadget cable support; > - added the remove() driver method which drives SHDN# GPIO low to save power; > - dropped vendor prefix from the ID GPIO property name; > - changed the GPIO property name suffix to "-gpios"; > - switched to usign extcon_set_cable_state_() API; > - switched to using the gpiod/sleeping 'gpiolib' APIs; > - addded error messages to max3355_probe(); > - added IRQF_NO_SUSPEND flasg to the devm_request_threaded_irq() call; > - renamed 'ret' variable to 'err' in max3355_probe(); > - expanded the Kconfig entry help text; > - added vendor name to the patch summary, the bindings document, the Kconfig > entry, the driver heading comment, the module description, and the change log; > - fixed up and reformatted the change log. > > Documentation/devicetree/bindings/extcon/extcon-max3355.txt | 21 + > drivers/extcon/Kconfig | 8 > drivers/extcon/Makefile | 1 > drivers/extcon/extcon-max3355.c | 153 ++++++++++++ > 4 files changed, 183 insertions(+) > > Index: extcon/Documentation/devicetree/bindings/extcon/extcon-max3355.txt > =================================================================== > --- /dev/null > +++ extcon/Documentation/devicetree/bindings/extcon/extcon-max3355.txt > @@ -0,0 +1,21 @@ > +Maxim Integrated MAX3355 USB OTG chip > +------------------------------------- > + > +MAX3355 integrates a charge pump and comparators to enable a system with an > +integrated USB OTG dual-role transceiver to function as a USB OTG dual-role > +device. > + > +Required properties: > +- compatible: should be "maxim,max3355"; > +- maxim,shdn-gpios: should contain a phandle and GPIO specifier for the GPIO pin > + connected to the MAX3355's SHDN# pin; > +- id-gpios: should contain a phandle and GPIO specifier for the GPIO pin > + connected to the MAX3355's ID_OUT pin. > + > +Example (Koelsch board): > + > + usb-otg { > + compatible = "maxim,max3355"; > + maxim,shdn-gpios = <&gpio2 4 GPIO_ACTIVE_LOW>; > + id-gpios = <&gpio5 31 GPIO_ACTIVE_HIGH>; > + }; > Index: extcon/drivers/extcon/Kconfig > =================================================================== > --- extcon.orig/drivers/extcon/Kconfig > +++ extcon/drivers/extcon/Kconfig > @@ -52,6 +52,14 @@ config EXTCON_MAX14577 > Maxim MAX14577/77836. The MAX14577/77836 MUIC is a USB port accessory > detector and switch. > > +config EXTCON_MAX3355 > + tristate "Maxim MAX3355 USB OTG EXTCON Support" > + help > + If you say yes here you get support for the USB OTG role detection by > + MAX3355. The MAX3355 chip integrates a charge pump and comparators to > + enable a system with an integrated USB OTG dual-role transceiver to > + function as an USB OTG dual-role device. > + > config EXTCON_MAX77693 > tristate "Maxim MAX77693 EXTCON Support" > depends on MFD_MAX77693 && INPUT > Index: extcon/drivers/extcon/Makefile > =================================================================== > --- extcon.orig/drivers/extcon/Makefile > +++ extcon/drivers/extcon/Makefile > @@ -8,6 +8,7 @@ obj-$(CONFIG_EXTCON_ARIZONA) += extcon-a > obj-$(CONFIG_EXTCON_AXP288) += extcon-axp288.o > obj-$(CONFIG_EXTCON_GPIO) += extcon-gpio.o > obj-$(CONFIG_EXTCON_MAX14577) += extcon-max14577.o > +obj-$(CONFIG_EXTCON_MAX3355) += extcon-max3355.o > obj-$(CONFIG_EXTCON_MAX77693) += extcon-max77693.o > obj-$(CONFIG_EXTCON_MAX77843) += extcon-max77843.o > obj-$(CONFIG_EXTCON_MAX8997) += extcon-max8997.o > Index: extcon/drivers/extcon/extcon-max3355.c > =================================================================== > --- /dev/null > +++ extcon/drivers/extcon/extcon-max3355.c > @@ -0,0 +1,153 @@ > +/* > + * Maxim Integrated MAX3355 USB OTG chip extcon driver > + * > + * Copyright (C) 2014 Cogent Embedded, Inc. > + * Author: Sergei Shtylyov <sergei.shtylyov@xxxxxxxxxxxxxxxxxx> > + * > + * 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. > + */ > + > +#include <linux/extcon.h> > +#include <linux/gpio.h> > +#include <linux/init.h> > +#include <linux/interrupt.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> > + > +struct max3355_data { > + struct extcon_dev *edev; > + struct gpio_desc *id_gpiod; > + struct gpio_desc *shdn_gpiod; > +}; > + > +static const unsigned int max3355_cable[] = { > + EXTCON_USB, > + EXTCON_USB_HOST, > + EXTCON_NONE, > +}; > + > +static irqreturn_t max3355_id_irq(int irq, void *dev_id) > +{ > + struct max3355_data *data = dev_id; > + int id = gpiod_get_value_cansleep(data->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_(data->edev, EXTCON_USB_HOST, false); > + extcon_set_cable_state_(data->edev, EXTCON_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_(data->edev, EXTCON_USB, false); > + extcon_set_cable_state_(data->edev, EXTCON_USB_HOST, true); > + } > + > + return IRQ_HANDLED; > +} > + > +static int max3355_probe(struct platform_device *pdev) > +{ > + struct device_node *np = pdev->dev.of_node; > + struct max3355_data *data; > + struct gpio_desc *gpiod; > + int irq, err; > + > + data = devm_kzalloc(&pdev->dev, sizeof(struct max3355_data), > + GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + data->edev = devm_extcon_dev_allocate(&pdev->dev, max3355_cable); > + if (IS_ERR(data->edev)) { > + dev_err(&pdev->dev, "failed to allocate extcon device\n"); > + return PTR_ERR(data->edev); > + } > + data->edev->name = kstrdup(np->name, GFP_KERNEL); > + > + gpiod = devm_gpiod_get(&pdev->dev, "id", GPIOD_IN); > + if (IS_ERR(gpiod)) { > + dev_err(&pdev->dev, "failed to get ID_OUT GPIO\n"); > + return PTR_ERR(gpiod); > + } > + data->id_gpiod = gpiod; > + > + gpiod = devm_gpiod_get(&pdev->dev, "maxim,shdn", GPIOD_OUT_HIGH); > + if (IS_ERR(gpiod)) { > + dev_err(&pdev->dev, "failed to get SHDN# GPIO\n"); > + return PTR_ERR(gpiod); > + } > + data->shdn_gpiod = gpiod; > + > + err = devm_extcon_dev_register(&pdev->dev, data->edev); > + if (err < 0) { > + dev_err(&pdev->dev, "failed to register extcon device\n"); > + return err; > + } > + > + irq = gpiod_to_irq(data->id_gpiod); > + if (irq < 0) { > + dev_err(&pdev->dev, "failed to translate ID_OUT GPIO to IRQ\n"); > + return irq; > + } > + > + err = devm_request_threaded_irq(&pdev->dev, irq, NULL, max3355_id_irq, > + IRQF_ONESHOT | IRQF_NO_SUSPEND | > + IRQF_TRIGGER_RISING | > + IRQF_TRIGGER_FALLING, > + pdev->name, data); > + if (err < 0) { > + dev_err(&pdev->dev, "failed to request ID_OUT IRQ\n"); > + return err; > + } > + > + platform_set_drvdata(pdev, data); > + > + /* Perform initial detection */ > + max3355_id_irq(irq, data); > + > + return 0; > +} > + > +static int max3355_remove(struct platform_device *pdev) > +{ > + struct max3355_data *data = platform_get_drvdata(pdev); > + > + gpiod_set_value_cansleep(data->shdn_gpiod, 0); > + > + return 0; > +} > + > +static const struct of_device_id max3355_match_table[] = { > + { .compatible = "maxim,max3355", }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, max3355_match_table); > + > +static struct platform_driver max3355_driver = { > + .probe = max3355_probe, > + .remove = max3355_remove, > + .driver = { > + .name = "extcon-max3355", > + .of_match_table = max3355_match_table, > + .owner = THIS_MODULE, > + }, > +}; > + > +module_platform_driver(max3355_driver); > + > +MODULE_AUTHOR("Sergei Shtylyov <sergei.shtylyov@xxxxxxxxxxxxxxxxxx>"); > +MODULE_DESCRIPTION("Maxim MAX3355 extcon driver"); > +MODULE_LICENSE("GPL v2"); > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > > -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html