Re: [U-Boot] [UBOOT RFC PATCH 02/13] usb: gadget: udc-core: Add minimal udc-core from linux kernel

Hi Kishon,

In order to support multiple USB device controllers in uboot, udc-core is needed.

Is it? In u-boot at best only one UDC is operational at a time.

udc-core also helps to cleanly link the USB peripheral driver with the gadget driver. Hence Ported minimal udc-core from linux kernel.

I'd appreciate the exact SHA for this udc-core.c code. And the SHA should be from some already released mainline code (like final 3.16), not any private branch nor linux-next.

Signed-off-by: Kishon Vijay Abraham I kishon@ti.com

drivers/usb/gadget/Makefile | 1 + drivers/usb/gadget/udc-core.c | 229 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 230 insertions(+) create mode 100644 drivers/usb/gadget/udc-core.c

diff --git a/drivers/usb/gadget/Makefile b/drivers/usb/gadget/Makefile index 66becdc..74875a2 100644 --- a/drivers/usb/gadget/Makefile +++ b/drivers/usb/gadget/Makefile @@ -19,6 +19,7 @@ obj-$(CONFIG_USBDOWNLOAD_GADGET) += g_dnl.o obj-$(CONFIG_DFU_FUNCTION) += f_dfu.o obj-$(CONFIG_USB_GADGET_MASS_STORAGE) += f_mass_storage.o obj-$(CONFIG_CMD_FASTBOOT) += f_fastboot.o +obj-y += udc-core.o endif ifdef CONFIG_USB_ETHER obj-y += ether.o diff --git a/drivers/usb/gadget/udc-core.c b/drivers/usb/gadget/udc-core.c new file mode 100644 index 0000000..bbe919c --- /dev/null +++ b/drivers/usb/gadget/udc-core.c @@ -0,0 +1,229 @@ +/**

• • udc-core.c - Core UDC Framework
• • Copyright (C) 2014 Texas Instruments Incorporated -

http://www.ti.com

• • Author: Felipe Balbi balbi@ti.com
• • Taken from Linux Kernel v3.16 (drivers/usb/gadget/udc-core.c) and

ported

• • to uboot.
• • SPDX-License-Identifier: GPL-2.0+

It seems like the author is the same, but the GPL license is different:

Original file ./drivers/usb/gadget/udc/udc-core.c

/** * udc.c - Core UDCFramework * * Copyright (C) 2010 TexasInstruments * Author: Felipe Balbibalbi@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 of * the License as published by the Free Software Foundation.

If Felipe don't mind then he should give you the permission to add + to the GPL2.

• */

+#include <linux/compat.h> +#include <malloc.h> +#include <asm/cache.h> +#include <common.h>

+#include <linux/usb/ch9.h> +#include <linux/usb/gadget.h>

+/**

• • struct usb_udc - describes one usb device controller
• • @driver - the gadget driver pointer. For use by the class code
• • @dev - the child device to the actual controller
• • @gadget - the gadget. For use by the class code
• • @list - for use by the udc class driver
• • This represents the internal data structure which is used by the

UDC-class

• • to hold information about udc driver and gadget together.
• */

+struct usb_udc {

• struct usb_gadget_driver *driver;
• struct usb_gadget *gadget;
• struct list_head list;

+};

+static LIST_HEAD(udc_list);

+void usb_gadget_set_state(struct usb_gadget *gadget,

• enum usb_device_state state)
  

+{

• gadget->state = state;

+}

+/**

• • usb_gadget_udc_start - tells usb device controller to start up
• • @gadget: The gadget we want to get started
• • @driver: The driver we want to bind to @gadget
• • This call is issued by the UDC Class driver when it's about
• • to register a gadget driver to the device controller, before
• • calling gadget driver's bind() method.
• • It allows the controller to be powered off until strictly
• • necessary to have it powered on.
• • Returns zero on success, else negative errno.
• */

+static inline int usb_gadget_udc_start(struct usb_gadget *gadget,

• struct usb_gadget_driver *driver)
  

+{

• return gadget->ops->udc_start(gadget, driver);

+}

+/**

• • usb_gadget_udc_stop - tells usb device controller we don't need

it anymore

• • @gadget: The device we want to stop activity
• • @driver: The driver to unbind from @gadget
• • This call is issued by the UDC Class driver after calling
• • gadget driver's unbind() method.
• • The details are implementation specific, but it can go as
• • far as powering off UDC completely and disable its data
• • line pullups.
• */

+static inline void usb_gadget_udc_stop(struct usb_gadget *gadget,

• struct usb_gadget_driver *driver)
  

+{

• gadget->ops->udc_stop(gadget, driver);

+}

+/**

• • usb_add_gadget_udc_release - adds a new gadget to the udc class

driver list

• • @parent: the parent device to this udc. Usually the controller

driver's

• • device.
• • @gadget: the gadget to be added to the list.
• • @release: a gadget release function.
• • Returns zero on success, negative errno otherwise.
• */

+int usb_add_gadget_udc_release(struct usb_gadget *gadget) +{

• struct usb_udc *udc;
• int ret = -ENOMEM;
• udc = kzalloc(sizeof(*udc), GFP_KERNEL);
• if (!udc)

• return ret;
  

• udc->gadget = gadget;
• list_add_tail(&udc->list, &udc_list);
• usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
• return 0;

+}

+/**

• • usb_add_gadget_udc - adds a new gadget to the udc class driver

list

• • @parent: the parent device to this udc. Usually the controller
• • driver's device.
• • @gadget: the gadget to be added to the list
• • Returns zero on success, negative errno otherwise.
• */

+int usb_add_gadget_udc(struct usb_gadget *gadget) +{

• return usb_add_gadget_udc_release(gadget);

+}

+static void usb_gadget_remove_driver(struct usb_udc *udc) +{

• dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",

• 	udc->gadget->name);
  

• usb_gadget_disconnect(udc->gadget);
• udc->driver->disconnect(udc->gadget);
• udc->driver->unbind(udc->gadget);
• usb_gadget_udc_stop(udc->gadget, NULL);
• udc->driver = NULL;

+}

+/**

• • usb_del_gadget_udc - deletes @udc from udc_list
• • @gadget: the gadget to be removed.
• • This, will call usb_gadget_unregister_driver() if
• • the @udc is still busy.
• */

+void usb_del_gadget_udc(struct usb_gadget *gadget) +{

• struct usb_udc *udc = NULL;
• list_for_each_entry(udc, &udc_list, list)

• if (udc->gadget == gadget)
  

• 	goto found;
  

• dev_err(gadget->dev.parent, "gadget not registered.\n");
• return;

+found:

• dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
• list_del(&udc->list);
• if (udc->driver)

• usb_gadget_remove_driver(udc);
  

• kfree(udc);

+}

+static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver) +{

• int ret;
• dev_dbg(&udc->dev, "registering UDC driver [%s]\n",

• 	driver->function);
  

• udc->driver = driver;
• ret = driver->bind(udc->gadget);
• if (ret)

• goto err1;
  

• ret = usb_gadget_udc_start(udc->gadget, driver);
• if (ret) {

• driver->unbind(udc->gadget);
  

• goto err1;
  

• }
• usb_gadget_connect(udc->gadget);
• return 0;

+err1:

• if (ret != -EISNAM)

• dev_err(&udc->dev, "failed to start %s: %d\n",
  

• 	udc->driver->function, ret);
  

• udc->driver = NULL;
• return ret;

+}

+int usb_gadget_register_driver(struct usb_gadget_driver *driver) +{

• struct usb_udc *udc = NULL;
• int ret;
• if (!driver || !driver->bind || !driver->setup)

• return -EINVAL;
  

• list_for_each_entry(udc, &udc_list, list) {

• /* For now we take the first one */
  

• if (!udc->driver)
  

• 	goto found;
  

• }
• debug("couldn't find an available UDC\n");
• return -ENODEV;

+found:

• ret = udc_bind_to_driver(udc, driver);
• return ret;

+}

+int usb_gadget_unregister_driver(struct usb_gadget_driver *driver) +{

• struct usb_udc *udc = NULL;
• int ret = -ENODEV;
• if (!driver || !driver->unbind)

• return -EINVAL;
  

• list_for_each_entry(udc, &udc_list, list)

• if (udc->driver == driver) {
  

• 	usb_gadget_remove_driver(udc);
  

• 	usb_gadget_set_state(udc->gadget,
  

• 			USB_STATE_NOTATTACHED);
  

• 	ret = 0;
  

• 	break;
  

• }
  

• return ret;

+}