drivers/usb/gadget/epautoconf.c - filogic/uboot - Gitiles

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * epautoconf.c -- endpoint autoconfiguration for usb gadget drivers
  *
  * Copyright (C) 2004 David Brownell
  *
  * Ported to U-Boot by: Thomas Smits <ts.smits@gmail.com> and
  *                      Remy Bohmer <linux@bohmer.net>
  */

 #include <linux/usb/ch9.h>
 #include <linux/errno.h>
 #include <linux/usb/gadget.h>
 #include <asm/unaligned.h>

 #define isdigit(c)      ('0' <= (c) && (c) <= '9')

 /* we must assign addresses for configurable endpoints (like net2280) */
 static unsigned epnum;

 /* #define MANY_ENDPOINTS */
 #ifdef MANY_ENDPOINTS
 /* more than 15 configurable endpoints */
 static unsigned in_epnum;
 #endif

 /*
  * This should work with endpoints from controller drivers sharing the
  * same endpoint naming convention.  By example:
  *
  *	- ep1, ep2, ... address is fixed, not direction or type
  *	- ep1in, ep2out, ... address and direction are fixed, not type
  *	- ep1-bulk, ep2-bulk, ... address and type are fixed, not direction
  *	- ep1in-bulk, ep2out-iso, ... all three are fixed
  *	- ep-* ... no functionality restrictions
  *
  * Type suffixes are "-bulk", "-iso", or "-int".  Numbers are decimal.
  * Less common restrictions are implied by gadget_is_*().
  *
  * NOTE:  each endpoint is unidirectional, as specified by its USB
  * descriptor; and isn't specific to a configuration or altsetting.
  */
 static int ep_matches(
 	struct usb_gadget		*gadget,
 	struct usb_ep			*ep,
 	struct usb_endpoint_descriptor	*desc
 )
 {
 	u8		type;
 	const char	*tmp;
 	u16		max;

 	/* endpoint already claimed? */
 	if (NULL != ep->driver_data)
 		return 0;

 	/* only support ep0 for portable CONTROL traffic */
 	type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
 	if (USB_ENDPOINT_XFER_CONTROL == type)
 		return 0;

 	/* some other naming convention */
 	if ('e' != ep->name[0])
 		return 0;

 	/* type-restriction:  "-iso", "-bulk", or "-int".
 	 * direction-restriction:  "in", "out".
 	 */
 	if ('-' != ep->name[2]) {
 		tmp = strrchr(ep->name, '-');
 		if (tmp) {
 			switch (type) {
 			case USB_ENDPOINT_XFER_INT:
 				/* bulk endpoints handle interrupt transfers,
 				 * except the toggle-quirky iso-synch kind
 				 */
 				if ('s' == tmp[2])	/* == "-iso" */
 					return 0;
 				break;
 			case USB_ENDPOINT_XFER_BULK:
 				if ('b' != tmp[1])	/* != "-bulk" */
 					return 0;
 				break;
 			case USB_ENDPOINT_XFER_ISOC:
 				if ('s' != tmp[2])	/* != "-iso" */
 					return 0;
 			}
 		} else {
 			tmp = ep->name + strlen(ep->name);
 		}

 		/* direction-restriction:  "..in-..", "out-.." */
 		tmp--;
 		if (!isdigit(*tmp)) {
 			if (desc->bEndpointAddress & USB_DIR_IN) {
 				if ('n' != *tmp)
 					return 0;
 			} else {
 				if ('t' != *tmp)
 					return 0;
 			}
 		}
 	}

 	/* endpoint maxpacket size is an input parameter, except for bulk
 	 * where it's an output parameter representing the full speed limit.
 	 * the usb spec fixes high speed bulk maxpacket at 512 bytes.
 	 */
 	max = 0x7ff & le16_to_cpu(get_unaligned(&desc->wMaxPacketSize));
 	switch (type) {
 	case USB_ENDPOINT_XFER_INT:
 		/* INT:  limit 64 bytes full speed, 1024 high speed */
 		if (!gadget->is_dualspeed && max > 64)
 			return 0;
 		/* FALLTHROUGH */

 	case USB_ENDPOINT_XFER_ISOC:
 		/* ISO:  limit 1023 bytes full speed, 1024 high speed */
 		if (ep->maxpacket < max)
 			return 0;
 		if (!gadget->is_dualspeed && max > 1023)
 			return 0;

 		/* BOTH:  "high bandwidth" works only at high speed */
 		if ((get_unaligned(&desc->wMaxPacketSize) &
 					__constant_cpu_to_le16(3<<11))) {
 			if (!gadget->is_dualspeed)
 				return 0;
 			/* configure your hardware with enough buffering!! */
 		}
 		break;
 	}

 	/* MATCH!! */

 	/* report address */
 	if (isdigit(ep->name[2])) {
 		u8	num = dectoul(&ep->name[2], NULL);
 		desc->bEndpointAddress |= num;
 #ifdef	MANY_ENDPOINTS
 	} else if (desc->bEndpointAddress & USB_DIR_IN) {
 		if (++in_epnum > 15)
 			return 0;
 		desc->bEndpointAddress = USB_DIR_IN | in_epnum;
 #endif
 	} else {
 		if (++epnum > 15)
 			return 0;
 		desc->bEndpointAddress |= epnum;
 	}

 	/* report (variable) full speed bulk maxpacket */
 	if (USB_ENDPOINT_XFER_BULK == type) {
 		int size = ep->maxpacket;

 		/* min() doesn't work on bitfields with gcc-3.5 */
 		if (size > 64)
 			size = 64;
 		put_unaligned(cpu_to_le16(size), &desc->wMaxPacketSize);
 	}

 	if (gadget->ops->ep_conf)
 		return gadget->ops->ep_conf(gadget, ep, desc);

 	return 1;
 }

 /**
  * usb_ep_autoconfig - choose an endpoint matching the descriptor
  * @gadget: The device to which the endpoint must belong.
  * @desc: Endpoint descriptor, with endpoint direction and transfer mode
  *	initialized.  For periodic transfers, the maximum packet
  *	size must also be initialized.  This is modified on success.
  *
  * By choosing an endpoint to use with the specified descriptor, this
  * routine simplifies writing gadget drivers that work with multiple
  * USB device controllers.  The endpoint would be passed later to
  * usb_ep_enable(), along with some descriptor.
  *
  * That second descriptor won't always be the same as the first one.
  * For example, isochronous endpoints can be autoconfigured for high
  * bandwidth, and then used in several lower bandwidth altsettings.
  * Also, high and full speed descriptors will be different.
  *
  * Be sure to examine and test the results of autoconfiguration on your
  * hardware.  This code may not make the best choices about how to use the
  * USB controller, and it can't know all the restrictions that may apply.
  * Some combinations of driver and hardware won't be able to autoconfigure.
  *
  * On success, this returns an un-claimed usb_ep, and modifies the endpoint
  * descriptor bEndpointAddress.  For bulk endpoints, the wMaxPacket value
  * is initialized as if the endpoint were used at full speed.  To prevent
  * the endpoint from being returned by a later autoconfig call, claim it
  * by assigning ep->driver_data to some non-null value.
  *
  * On failure, this returns a null endpoint descriptor.
  */
 struct usb_ep *usb_ep_autoconfig(
 	struct usb_gadget		*gadget,
 	struct usb_endpoint_descriptor	*desc
 )
 {
 	struct usb_ep *ep;

 	if (gadget->ops->match_ep) {
 		ep = gadget->ops->match_ep(gadget, desc, NULL);
 		if (ep && ep_matches(gadget, ep, desc))
 			return ep;
 	}

 	/* Second, look at endpoints until an unclaimed one looks usable */
 	list_for_each_entry(ep, &gadget->ep_list, ep_list) {
 		if (ep_matches(gadget, ep, desc))
 			return ep;
 	}

 	/* Fail */
 	return NULL;
 }

 /**
  * usb_ep_autoconfig_reset - reset endpoint autoconfig state
  * @gadget: device for which autoconfig state will be reset
  *
  * Use this for devices where one configuration may need to assign
  * endpoint resources very differently from the next one.  It clears
  * state such as ep->driver_data and the record of assigned endpoints
  * used by usb_ep_autoconfig().
  */
 void usb_ep_autoconfig_reset(struct usb_gadget *gadget)
 {
 	struct usb_ep	*ep;

 	list_for_each_entry(ep, &gadget->ep_list, ep_list) {
 		ep->driver_data = NULL;
 	}
 #ifdef	MANY_ENDPOINTS
 	in_epnum = 0;
 #endif
 	epnum = 0;
 }
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* epautoconf.c -- endpoint autoconfiguration for usb gadget drivers
	*
	* Copyright (C) 2004 David Brownell
	*
	* Ported to U-Boot by: Thomas Smits <ts.smits@gmail.com> and
	* Remy Bohmer <linux@bohmer.net>
	*/

	#include <linux/usb/ch9.h>
	#include <linux/errno.h>
	#include <linux/usb/gadget.h>
	#include <asm/unaligned.h>

	#define isdigit(c) ('0' <= (c) && (c) <= '9')

	/* we must assign addresses for configurable endpoints (like net2280) */
	static unsigned epnum;

	/* #define MANY_ENDPOINTS */
	#ifdef MANY_ENDPOINTS
	/* more than 15 configurable endpoints */
	static unsigned in_epnum;
	#endif

	/*
	* This should work with endpoints from controller drivers sharing the
	* same endpoint naming convention. By example:
	*
	* - ep1, ep2, ... address is fixed, not direction or type
	* - ep1in, ep2out, ... address and direction are fixed, not type
	* - ep1-bulk, ep2-bulk, ... address and type are fixed, not direction
	* - ep1in-bulk, ep2out-iso, ... all three are fixed
	* - ep-* ... no functionality restrictions
	*
	* Type suffixes are "-bulk", "-iso", or "-int". Numbers are decimal.
	* Less common restrictions are implied by gadget_is_*().
	*
	* NOTE: each endpoint is unidirectional, as specified by its USB
	* descriptor; and isn't specific to a configuration or altsetting.
	*/
	static int ep_matches(
	struct usb_gadget *gadget,
	struct usb_ep *ep,
	struct usb_endpoint_descriptor *desc
	)
	{
	u8 type;
	const char *tmp;
	u16 max;

	/* endpoint already claimed? */
	if (NULL != ep->driver_data)
	return 0;

	/* only support ep0 for portable CONTROL traffic */
	type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
	if (USB_ENDPOINT_XFER_CONTROL == type)
	return 0;

	/* some other naming convention */
	if ('e' != ep->name[0])
	return 0;

	/* type-restriction: "-iso", "-bulk", or "-int".
	* direction-restriction: "in", "out".
	*/
	if ('-' != ep->name[2]) {
	tmp = strrchr(ep->name, '-');
	if (tmp) {
	switch (type) {
	case USB_ENDPOINT_XFER_INT:
	/* bulk endpoints handle interrupt transfers,
	* except the toggle-quirky iso-synch kind
	*/
	if ('s' == tmp[2]) /* == "-iso" */
	return 0;
	break;
	case USB_ENDPOINT_XFER_BULK:
	if ('b' != tmp[1]) /* != "-bulk" */
	return 0;
	break;
	case USB_ENDPOINT_XFER_ISOC:
	if ('s' != tmp[2]) /* != "-iso" */
	return 0;
	}
	} else {
	tmp = ep->name + strlen(ep->name);
	}

	/* direction-restriction: "..in-..", "out-.." */
	tmp--;
	if (!isdigit(*tmp)) {
	if (desc->bEndpointAddress & USB_DIR_IN) {
	if ('n' != *tmp)
	return 0;
	} else {
	if ('t' != *tmp)
	return 0;
	}
	}
	}

	/* endpoint maxpacket size is an input parameter, except for bulk
	* where it's an output parameter representing the full speed limit.
	* the usb spec fixes high speed bulk maxpacket at 512 bytes.
	*/
	max = 0x7ff & le16_to_cpu(get_unaligned(&desc->wMaxPacketSize));
	switch (type) {
	case USB_ENDPOINT_XFER_INT:
	/* INT: limit 64 bytes full speed, 1024 high speed */
	if (!gadget->is_dualspeed && max > 64)
	return 0;
	/* FALLTHROUGH */

	case USB_ENDPOINT_XFER_ISOC:
	/* ISO: limit 1023 bytes full speed, 1024 high speed */
	if (ep->maxpacket < max)
	return 0;
	if (!gadget->is_dualspeed && max > 1023)
	return 0;

	/* BOTH: "high bandwidth" works only at high speed */
	if ((get_unaligned(&desc->wMaxPacketSize) &
	__constant_cpu_to_le16(3<<11))) {
	if (!gadget->is_dualspeed)
	return 0;
	/* configure your hardware with enough buffering!! */
	}
	break;
	}

	/* MATCH!! */

	/* report address */
	if (isdigit(ep->name[2])) {
	u8 num = dectoul(&ep->name[2], NULL);
	desc->bEndpointAddress \|= num;
	#ifdef MANY_ENDPOINTS
	} else if (desc->bEndpointAddress & USB_DIR_IN) {
	if (++in_epnum > 15)
	return 0;
	desc->bEndpointAddress = USB_DIR_IN \| in_epnum;
	#endif
	} else {
	if (++epnum > 15)
	return 0;
	desc->bEndpointAddress \|= epnum;
	}

	/* report (variable) full speed bulk maxpacket */
	if (USB_ENDPOINT_XFER_BULK == type) {
	int size = ep->maxpacket;

	/* min() doesn't work on bitfields with gcc-3.5 */
	if (size > 64)
	size = 64;
	put_unaligned(cpu_to_le16(size), &desc->wMaxPacketSize);
	}

	if (gadget->ops->ep_conf)
	return gadget->ops->ep_conf(gadget, ep, desc);

	return 1;
	}

	/**
	* usb_ep_autoconfig - choose an endpoint matching the descriptor
	* @gadget: The device to which the endpoint must belong.
	* @desc: Endpoint descriptor, with endpoint direction and transfer mode
	* initialized. For periodic transfers, the maximum packet
	* size must also be initialized. This is modified on success.
	*
	* By choosing an endpoint to use with the specified descriptor, this
	* routine simplifies writing gadget drivers that work with multiple
	* USB device controllers. The endpoint would be passed later to
	* usb_ep_enable(), along with some descriptor.
	*
	* That second descriptor won't always be the same as the first one.
	* For example, isochronous endpoints can be autoconfigured for high
	* bandwidth, and then used in several lower bandwidth altsettings.
	* Also, high and full speed descriptors will be different.
	*
	* Be sure to examine and test the results of autoconfiguration on your
	* hardware. This code may not make the best choices about how to use the
	* USB controller, and it can't know all the restrictions that may apply.
	* Some combinations of driver and hardware won't be able to autoconfigure.
	*
	* On success, this returns an un-claimed usb_ep, and modifies the endpoint
	* descriptor bEndpointAddress. For bulk endpoints, the wMaxPacket value
	* is initialized as if the endpoint were used at full speed. To prevent
	* the endpoint from being returned by a later autoconfig call, claim it
	* by assigning ep->driver_data to some non-null value.
	*
	* On failure, this returns a null endpoint descriptor.
	*/
	struct usb_ep *usb_ep_autoconfig(
	struct usb_gadget *gadget,
	struct usb_endpoint_descriptor *desc
	)
	{
	struct usb_ep *ep;

	if (gadget->ops->match_ep) {
	ep = gadget->ops->match_ep(gadget, desc, NULL);
	if (ep && ep_matches(gadget, ep, desc))
	return ep;
	}

	/* Second, look at endpoints until an unclaimed one looks usable */
	list_for_each_entry(ep, &gadget->ep_list, ep_list) {
	if (ep_matches(gadget, ep, desc))
	return ep;
	}

	/* Fail */
	return NULL;
	}

	/**
	* usb_ep_autoconfig_reset - reset endpoint autoconfig state
	* @gadget: device for which autoconfig state will be reset
	*
	* Use this for devices where one configuration may need to assign
	* endpoint resources very differently from the next one. It clears
	* state such as ep->driver_data and the record of assigned endpoints
	* used by usb_ep_autoconfig().
	*/
	void usb_ep_autoconfig_reset(struct usb_gadget *gadget)
	{
	struct usb_ep *ep;

	list_for_each_entry(ep, &gadget->ep_list, ep_list) {
	ep->driver_data = NULL;
	}
	#ifdef MANY_ENDPOINTS
	in_epnum = 0;
	#endif
	epnum = 0;
	}