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Diffstat (limited to 'drivers/usb/gadget/epautoconf.c')
| -rw-r--r-- | drivers/usb/gadget/epautoconf.c | 310 |
1 files changed, 310 insertions, 0 deletions
diff --git a/drivers/usb/gadget/epautoconf.c b/drivers/usb/gadget/epautoconf.c new file mode 100644 index 00000000000..f7c6d758e1b --- /dev/null +++ b/drivers/usb/gadget/epautoconf.c @@ -0,0 +1,310 @@ +/* + * epautoconf.c -- endpoint autoconfiguration for usb gadget drivers + * + * Copyright (C) 2004 David Brownell + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * 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, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/types.h> +#include <linux/device.h> + +#include <linux/ctype.h> +#include <linux/string.h> + +#include <linux/usb_ch9.h> +#include <linux/usb_gadget.h> + +#include "gadget_chips.h" + + +/* we must assign addresses for configurable endpoints (like net2280) */ +static __initdata unsigned epnum; + +// #define MANY_ENDPOINTS +#ifdef MANY_ENDPOINTS +/* more than 15 configurable endpoints */ +static __initdata 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 __init +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 (0 != 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; + /* for now, avoid PXA "interrupt-in"; + * it's documented as never using DATA1. + */ + if (gadget_is_pxa (gadget) + && 'i' == tmp [1]) + 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_cpup (&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 ((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 = simple_strtol (&ep->name [2], NULL, 10); + 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; + desc->wMaxPacketSize = cpu_to_le16(size); + } + return 1; +} + +static struct usb_ep * __init +find_ep (struct usb_gadget *gadget, const char *name) +{ + struct usb_ep *ep; + + list_for_each_entry (ep, &gadget->ep_list, ep_list) { + if (0 == strcmp (ep->name, name)) + return ep; + } + return NULL; +} + +/** + * 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 * __init usb_ep_autoconfig ( + struct usb_gadget *gadget, + struct usb_endpoint_descriptor *desc +) +{ + struct usb_ep *ep; + u8 type; + + type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK; + + /* First, apply chip-specific "best usage" knowledge. + * This might make a good usb_gadget_ops hook ... + */ + if (gadget_is_net2280 (gadget) && type == USB_ENDPOINT_XFER_INT) { + /* ep-e, ep-f are PIO with only 64 byte fifos */ + ep = find_ep (gadget, "ep-e"); + if (ep && ep_matches (gadget, ep, desc)) + return ep; + ep = find_ep (gadget, "ep-f"); + if (ep && ep_matches (gadget, ep, desc)) + return ep; + + } else if (gadget_is_goku (gadget)) { + if (USB_ENDPOINT_XFER_INT == type) { + /* single buffering is enough */ + ep = find_ep (gadget, "ep3-bulk"); + if (ep && ep_matches (gadget, ep, desc)) + return ep; + } else if (USB_ENDPOINT_XFER_BULK == type + && (USB_DIR_IN & desc->bEndpointAddress)) { + /* DMA may be available */ + ep = find_ep (gadget, "ep2-bulk"); + if (ep && ep_matches (gadget, ep, desc)) + return ep; + } + + } else if (gadget_is_sh (gadget) && USB_ENDPOINT_XFER_INT == type) { + /* single buffering is enough; maybe 8 byte fifo is too */ + ep = find_ep (gadget, "ep3in-bulk"); + if (ep && ep_matches (gadget, ep, desc)) + return ep; + + } else if (gadget_is_mq11xx (gadget) && USB_ENDPOINT_XFER_INT == type) { + ep = find_ep (gadget, "ep1-bulk"); + 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 __init 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; +} + |