Add USB DRD library. This Library facilitates to switch roles between HOST and Device modes. A DRD should be added to the library using usb_drd_add(). Register the HOST and UDC using usb_drd_register_hcd/udc(). Un-Register the HOST and UDC using usb_drd_unregister_hcd/udc(). Depending on the state of IP - Call the following to start/stop HOST controller usb_drd_start/stop_hcd(). This internally calls usb_add/remove_hcd() or IP specific low level start/stop defined in ll_start/stop Call the following to start/stop UDC usb_drd_start/stop_udc(). This internally calls udc_start/udc_stop() or IP specific low level start/stop defined in ll_start/stop Signed-off-by: George Cherian <george.cherian@xxxxxx> --- drivers/usb/Kconfig | 15 ++ drivers/usb/common/Makefile | 1 + drivers/usb/common/drd-lib.c | 346 +++++++++++++++++++++++++++++++++++++++++++ include/linux/usb/drd.h | 77 ++++++++++ 4 files changed, 439 insertions(+) create mode 100644 drivers/usb/common/drd-lib.c create mode 100644 include/linux/usb/drd.h diff --git a/drivers/usb/Kconfig b/drivers/usb/Kconfig index ae481c3..ea0d944 100644 --- a/drivers/usb/Kconfig +++ b/drivers/usb/Kconfig @@ -34,6 +34,21 @@ config USB_COMMON default y depends on USB || USB_GADGET +config DRD_LIB + tristate "DRD Library support" + default y + depends on USB && USB_GADGET + ---help--- + This option adds DRD Library support for Universal Serial Bus (USB). + DRD Library faciliatets the Role switching by HOST and DEVICE roles, + If your hardware has a Dual Role Device. + + The DRD Library uses USB core API's to start/stop HOST controllers, + UDC API's to start/stop DEVICE controllers, ther by enabling to + switch roles between HOST and Device modes. + + Say N if unsure. + config USB_ARCH_HAS_HCD def_bool y diff --git a/drivers/usb/common/Makefile b/drivers/usb/common/Makefile index ca2f8bd..e2c1593 100644 --- a/drivers/usb/common/Makefile +++ b/drivers/usb/common/Makefile @@ -7,3 +7,4 @@ usb-common-y += common.o usb-common-$(CONFIG_USB_LED_TRIG) += led.o obj-$(CONFIG_USB_OTG_FSM) += usb-otg-fsm.o +obj-$(CONFIG_DRD_LIB) += drd-lib.o diff --git a/drivers/usb/common/drd-lib.c b/drivers/usb/common/drd-lib.c new file mode 100644 index 0000000..6159436 --- /dev/null +++ b/drivers/usb/common/drd-lib.c @@ -0,0 +1,346 @@ +/** + * drd-lib.c - USB DRD library functions + * + * Copyright (C) 2014 Texas Instruments + * Author: George Cherian <george.cherian@xxxxxx> + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 of + * the License 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. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/device.h> +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/usb.h> + +#include <linux/usb/hcd.h> +#include <linux/usb/gadget.h> +#include <linux/usb/drd.h> + +/** + * struct usb_drd - describes one dual role device + * @host - the HOST controller device of this drd + * @gadget - the gadget of drd + * @parent - the device to the actual controller + * @list - for use by the drd lib + * @state - specifies the current state + * + * This represents the internal data structure which is used by the UDC-class + * to hold information about udc driver and gadget together. + */ +struct usb_drd { + struct usb_drd_host *host; + struct usb_drd_gadget *gadget; + struct device *parent; + struct list_head list; + unsigned int state; +}; + +static LIST_HEAD(drd_list); +static DEFINE_SPINLOCK(drd_lock); + +static struct usb_drd *usb_drd_get_dev(struct device *parent) +{ + struct usb_drd *drd; + + spin_lock(&drd_lock); + list_for_each_entry(drd, &drd_list, list) + if (drd->parent == parent) + goto out; + drd = NULL; +out: + spin_unlock(&drd_lock); + + return drd; +} + +int usb_drd_get_state(struct device *parent) +{ + struct usb_drd *drd; + + drd = usb_drd_get_dev(parent); + if (!drd) + return -ENODEV; + + return drd->state; +} +EXPORT_SYMBOL_GPL(usb_drd_get_state); + +int usb_drd_release(struct device *parent) +{ + struct usb_drd *drd; + int ret; + + spin_lock(&drd_lock); + list_for_each_entry(drd, &drd_list, list) { + if (drd->parent == parent) { + kfree(drd); + ret = 0; + goto out; + } + } + ret = -ENODEV; +out: + spin_unlock(&drd_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_drd_release); + +int usb_drd_add(struct device *parent) +{ + struct usb_drd *drd; + + drd = kzalloc(sizeof(*drd), GFP_KERNEL); + if (!drd) + return -ENOMEM; + + spin_lock(&drd_lock); + drd->parent = parent; + list_add_tail(&drd->list, &drd_list); + drd->state = DRD_UNREGISTERED; + + spin_unlock(&drd_lock); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_drd_add); + +int usb_drd_register_hcd(struct device *parent, struct usb_drd_host *host) +{ + struct usb_drd *drd; + + drd = usb_drd_get_dev(parent); + if (!drd) + return -ENODEV; + + spin_lock(&drd_lock); + drd->host = host; + drd->state |= DRD_HOST_REGISTERED | DRD_HOST_ACTIVE; + spin_unlock(&drd_lock); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_drd_register_hcd); + +int usb_drd_unregister_hcd(struct device *parent) +{ + struct usb_drd *drd; + + drd = usb_drd_get_dev(parent); + if (!drd) + return -ENODEV; + + spin_lock(&drd_lock); + drd->state &= ~(DRD_HOST_REGISTERED | DRD_HOST_ACTIVE); + spin_unlock(&drd_lock); + kfree(drd->host); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_drd_unregister_hcd); + +int usb_drd_start_hcd(struct device *parent) +{ + struct usb_drd *drd; + struct usb_drd_setup *setup; + + drd = usb_drd_get_dev(parent); + if (!drd) + return -ENODEV; + + if (WARN_ON(!(drd->state & DRD_HOST_REGISTERED))) + return -EINVAL; + + setup = drd->host->host_setup; + if (setup && setup->ll_start) + setup->ll_start(setup->data); + + usb_add_hcd(drd->host->main_hcd, + drd->host->hcd_irq, IRQF_SHARED); + if (drd->host->shared_hcd) + usb_add_hcd(drd->host->shared_hcd, + drd->host->hcd_irq, IRQF_SHARED); + + spin_lock(&drd_lock); + drd->state |= DRD_HOST_ACTIVE; + spin_unlock(&drd_lock); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_drd_start_hcd); + +int usb_drd_stop_hcd(struct device *parent) +{ + struct usb_drd *drd; + struct usb_drd_setup *setup; + + drd = usb_drd_get_dev(parent); + if (!drd) + return -ENODEV; + + if (WARN_ON(!(drd->state & DRD_HOST_ACTIVE))) + return -EINVAL; + + setup = drd->host->host_setup; + if (setup && setup->ll_stop) + setup->ll_stop(setup->data); + if (drd->host->shared_hcd) + usb_remove_hcd(drd->host->shared_hcd); + + usb_remove_hcd(drd->host->main_hcd); + + spin_lock(&drd_lock); + drd->state = drd->state & ~DRD_HOST_ACTIVE; + spin_unlock(&drd_lock); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_drd_stop_hcd); + +int usb_drd_register_udc(struct device *parent, struct usb_drd_gadget *gadget) +{ + struct usb_drd *drd; + + drd = usb_drd_get_dev(parent); + if (!drd) + return -ENODEV; + + spin_lock(&drd_lock); + drd->gadget = gadget; + drd->state |= DRD_DEVICE_REGISTERED; + if (drd->gadget->g_driver) + drd->state |= DRD_DEVICE_ACTIVE; + + spin_unlock(&drd_lock); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_drd_register_udc); + +int usb_drd_register_udc_driver(struct device *parent, + struct usb_gadget_driver *driver) +{ + struct usb_drd *drd; + + drd = usb_drd_get_dev(parent); + if (!drd) + return -ENODEV; + + spin_lock(&drd_lock); + drd->gadget->g_driver = driver; + drd->state |= DRD_DEVICE_ACTIVE; + spin_unlock(&drd_lock); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_drd_register_udc_driver); + +int usb_drd_unregister_udc(struct device *parent) +{ + struct usb_drd *drd; + + drd = usb_drd_get_dev(parent); + if (!drd) + return -ENODEV; + + spin_lock(&drd_lock); + drd->state &= ~(DRD_DEVICE_REGISTERED | DRD_DEVICE_ACTIVE); + spin_unlock(&drd_lock); + kfree(drd->gadget->gadget_setup); + kfree(drd->gadget); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_drd_unregister_udc); + +int usb_drd_unregister_udc_driver(struct device *parent) +{ + struct usb_drd *drd; + struct usb_drd_gadget *drd_gadget; + + drd = usb_drd_get_dev(parent); + if (!drd) + return -ENODEV; + drd_gadget = drd->gadget; + + spin_lock(&drd_lock); + drd->state &= ~DRD_DEVICE_ACTIVE; + drd_gadget->g_driver = NULL; + spin_unlock(&drd_lock); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_drd_unregister_udc_driver); + +int usb_drd_start_udc(struct device *parent) +{ + struct usb_drd *drd; + struct usb_drd_gadget *drd_gadget; + struct usb_drd_setup *setup; + + drd = usb_drd_get_dev(parent); + if (!drd) + return -ENODEV; + + if (WARN_ON(!(drd->state & DRD_DEVICE_REGISTERED))) + return -EINVAL; + + drd_gadget = drd->gadget; + setup = drd_gadget->gadget_setup; + + if (setup && setup->ll_start) + setup->ll_start(setup->data); + + usb_add_gadget_udc_release(parent, drd_gadget->gadget, + setup->ll_release); + spin_lock(&drd_lock); + drd->state |= DRD_DEVICE_ACTIVE; + spin_unlock(&drd_lock); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_drd_start_udc); + +int usb_drd_stop_udc(struct device *parent) +{ + struct usb_drd *drd; + struct usb_drd_gadget *drd_gadget; + struct usb_drd_setup *setup; + + drd = usb_drd_get_dev(parent); + if (!drd) + return -ENODEV; + + if (WARN_ON(!(drd->state & DRD_DEVICE_REGISTERED))) + return -EINVAL; + + drd_gadget = drd->gadget; + setup = drd_gadget->gadget_setup; + if (setup && setup->ll_stop) + setup->ll_stop(setup->data); + + usb_del_gadget_udc(drd_gadget->gadget); + + spin_lock(&drd_lock); + drd->state = drd->state & ~DRD_DEVICE_ACTIVE; + spin_unlock(&drd_lock); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_drd_stop_udc); + +MODULE_DESCRIPTION("USB-DRD Library"); +MODULE_AUTHOR("George Cherian <george.cherian@xxxxxx>"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/usb/drd.h b/include/linux/usb/drd.h new file mode 100644 index 0000000..71c64dc --- /dev/null +++ b/include/linux/usb/drd.h @@ -0,0 +1,77 @@ +#include <linux/usb/gadget.h> +#include <linux/usb/otg.h> +#include <linux/usb/hcd.h> + +struct usb_drd_setup { + int (*ll_start)(void *); + int (*ll_stop)(void *); + void (*ll_release)(struct device *); + void *data; +}; + +struct usb_drd_host { + struct usb_hcd *main_hcd; + struct usb_hcd *shared_hcd; + int hcd_irq; + struct usb_drd_setup *host_setup; +}; + +struct usb_drd_gadget { + struct usb_gadget_driver *g_driver; + struct usb_gadget *gadget; + struct usb_drd_setup *gadget_setup; +}; + +#define DRD_UNREGISTERED 0x0 +#define DRD_DEVICE_REGISTERED 0x1 +#define DRD_HOST_REGISTERED 0x2 +#define DRD_HOST_ACTIVE 0x4 +#define DRD_DEVICE_ACTIVE 0x8 + +#if IS_ENABLED(CONFIG_DRD_LIB) +int usb_drd_release(struct device *parent); +int usb_drd_add(struct device *parent); +int usb_drd_register_udc(struct device *parent, + struct usb_drd_gadget *gadget); +int usb_drd_register_udc_driver(struct device *parent, + struct usb_gadget_driver *driver); +int usb_drd_unregister_udc(struct device *parent); +int usb_drd_unregister_udc_driver(struct device *parent); +int usb_drd_register_hcd(struct device *parent, + struct usb_drd_host *host); +int usb_drd_unregister_hcd(struct device *parent); +int usb_drd_start_hcd(struct device *parent); +int usb_drd_stop_hcd(struct device *parent); +int usb_drd_start_udc(struct device *parent); +int usb_drd_stop_udc(struct device *parent); +int usb_drd_get_state(struct device *parent); +#else +static inline int usb_drd_release(struct device *parent) +{ return 0; } +static inline int usb_drd_add(struct device *parent) +{ return 0; } +static inline int usb_drd_register_udc(struct device *parent, + struct usb_drd_gadget *gadget) +{ return 0; } +static inline int usb_drd_register_udc_driver(struct device *parent, + struct usb_gadget_driver *driver) +{ return 0; } +static inline int usb_drd_unregister_udc(struct device *parent, + struct usb_drd_gadget *gadget) +{ return 0; } +static inline int usb_drd_unregister_udc_driver(struct device *parent) +{ return 0; } +static inline int usb_drd_register_hcd(struct device *parent, + struct usb_drd_host *host) +{ return 0; } +static inline int usb_drd_unregister_hcd(struct device *parent) +{ return 0; } +static inline int usb_drd_stop_hcd(struct device *parent) +{ return 0; } +static inline int usb_drd_start_udc(struct device *parent) +{ return 0; } +static inline int usb_drd_stop_udc(struct device *parent) +{ return 0; } +static inline int usb_drd_get_state(struct device *parent) +{ return 0; } +#endif -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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