diff options
| -rw-r--r-- | drivers/usb/gadget/f_loopback.c | 381 | ||||
| -rw-r--r-- | drivers/usb/gadget/g_zero.h | 2 |
2 files changed, 383 insertions, 0 deletions
diff --git a/drivers/usb/gadget/f_loopback.c b/drivers/usb/gadget/f_loopback.c new file mode 100644 index 00000000000..eda4cde72c8 --- /dev/null +++ b/drivers/usb/gadget/f_loopback.c @@ -0,0 +1,381 @@ +/* + * f_loopback.c - USB peripheral loopback configuration driver + * + * Copyright (C) 2003-2008 David Brownell + * Copyright (C) 2008 by Nokia Corporation + * + * 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 + */ + +/* #define VERBOSE_DEBUG */ + +#include <linux/kernel.h> +#include <linux/utsname.h> +#include <linux/device.h> + +#include "g_zero.h" +#include "gadget_chips.h" + + +/* + * LOOPBACK FUNCTION ... a testing vehicle for USB peripherals, + * + * This takes messages of various sizes written OUT to a device, and loops + * them back so they can be read IN from it. It has been used by certain + * test applications. It supports limited testing of data queueing logic. + * + * + * This is currently packaged as a configuration driver, which can't be + * combined with other functions to make composite devices. However, it + * can be combined with other independent configurations. + */ +struct f_loopback { + struct usb_function function; + + struct usb_ep *in_ep; + struct usb_ep *out_ep; +}; + +static inline struct f_loopback *func_to_loop(struct usb_function *f) +{ + return container_of(f, struct f_loopback, function); +} + +static unsigned qlen = 32; +module_param(qlen, uint, 0); +MODULE_PARM_DESC(qlenn, "depth of loopback queue"); + +/*-------------------------------------------------------------------------*/ + +static struct usb_interface_descriptor loopback_intf = { + .bLength = sizeof loopback_intf, + .bDescriptorType = USB_DT_INTERFACE, + + .bNumEndpoints = 2, + .bInterfaceClass = USB_CLASS_VENDOR_SPEC, + /* .iInterface = DYNAMIC */ +}; + +/* full speed support: */ + +static struct usb_endpoint_descriptor fs_source_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_IN, + .bmAttributes = USB_ENDPOINT_XFER_BULK, +}; + +static struct usb_endpoint_descriptor fs_sink_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_OUT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, +}; + +static struct usb_descriptor_header *fs_loopback_descs[] = { + (struct usb_descriptor_header *) &loopback_intf, + (struct usb_descriptor_header *) &fs_sink_desc, + (struct usb_descriptor_header *) &fs_source_desc, + NULL, +}; + +/* high speed support: */ + +static struct usb_endpoint_descriptor hs_source_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = __constant_cpu_to_le16(512), +}; + +static struct usb_endpoint_descriptor hs_sink_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = __constant_cpu_to_le16(512), +}; + +static struct usb_descriptor_header *hs_loopback_descs[] = { + (struct usb_descriptor_header *) &loopback_intf, + (struct usb_descriptor_header *) &hs_source_desc, + (struct usb_descriptor_header *) &hs_sink_desc, + NULL, +}; + +/* function-specific strings: */ + +static struct usb_string strings_loopback[] = { + [0].s = "loop input to output", + { } /* end of list */ +}; + +static struct usb_gadget_strings stringtab_loop = { + .language = 0x0409, /* en-us */ + .strings = strings_loopback, +}; + +static struct usb_gadget_strings *loopback_strings[] = { + &stringtab_loop, + NULL, +}; + +/*-------------------------------------------------------------------------*/ + +static int __init +loopback_bind(struct usb_configuration *c, struct usb_function *f) +{ + struct usb_composite_dev *cdev = c->cdev; + struct f_loopback *loop = func_to_loop(f); + int id; + + /* allocate interface ID(s) */ + id = usb_interface_id(c, f); + if (id < 0) + return id; + loopback_intf.bInterfaceNumber = id; + + /* allocate endpoints */ + + loop->in_ep = usb_ep_autoconfig(cdev->gadget, &fs_source_desc); + if (!loop->in_ep) { +autoconf_fail: + ERROR(cdev, "%s: can't autoconfigure on %s\n", + f->name, cdev->gadget->name); + return -ENODEV; + } + loop->in_ep->driver_data = cdev; /* claim */ + + loop->out_ep = usb_ep_autoconfig(cdev->gadget, &fs_sink_desc); + if (!loop->out_ep) + goto autoconf_fail; + loop->out_ep->driver_data = cdev; /* claim */ + + /* support high speed hardware */ + if (gadget_is_dualspeed(c->cdev->gadget)) { + hs_source_desc.bEndpointAddress = + fs_source_desc.bEndpointAddress; + hs_sink_desc.bEndpointAddress = + fs_sink_desc.bEndpointAddress; + f->hs_descriptors = hs_loopback_descs; + } + + DBG(cdev, "%s speed %s: IN/%s, OUT/%s\n", + gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full", + f->name, loop->in_ep->name, loop->out_ep->name); + return 0; +} + +static void +loopback_unbind(struct usb_configuration *c, struct usb_function *f) +{ + kfree(func_to_loop(f)); +} + +static void loopback_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct f_loopback *loop = ep->driver_data; + struct usb_composite_dev *cdev = loop->function.config->cdev; + int status = req->status; + + switch (status) { + + case 0: /* normal completion? */ + if (ep == loop->out_ep) { + /* loop this OUT packet back IN to the host */ + req->zero = (req->actual < req->length); + req->length = req->actual; + status = usb_ep_queue(loop->in_ep, req, GFP_ATOMIC); + if (status == 0) + return; + + /* "should never get here" */ + ERROR(cdev, "can't loop %s to %s: %d\n", + ep->name, loop->in_ep->name, + status); + } + + /* queue the buffer for some later OUT packet */ + req->length = buflen; + status = usb_ep_queue(loop->out_ep, req, GFP_ATOMIC); + if (status == 0) + return; + + /* "should never get here" */ + /* FALLTHROUGH */ + + default: + ERROR(cdev, "%s loop complete --> %d, %d/%d\n", ep->name, + status, req->actual, req->length); + /* FALLTHROUGH */ + + /* NOTE: since this driver doesn't maintain an explicit record + * of requests it submitted (just maintains qlen count), we + * rely on the hardware driver to clean up on disconnect or + * endpoint disable. + */ + case -ECONNABORTED: /* hardware forced ep reset */ + case -ECONNRESET: /* request dequeued */ + case -ESHUTDOWN: /* disconnect from host */ + free_ep_req(ep, req); + return; + } +} + +static void disable_loopback(struct f_loopback *loop) +{ + struct usb_composite_dev *cdev; + + cdev = loop->function.config->cdev; + disable_endpoints(cdev, loop->in_ep, loop->out_ep); + VDBG(cdev, "%s disabled\n", loop->function.name); +} + +static int +enable_loopback(struct usb_composite_dev *cdev, struct f_loopback *loop) +{ + int result = 0; + const struct usb_endpoint_descriptor *src, *sink; + struct usb_ep *ep; + struct usb_request *req; + unsigned i; + + src = ep_choose(cdev->gadget, &hs_source_desc, &fs_source_desc); + sink = ep_choose(cdev->gadget, &hs_sink_desc, &fs_sink_desc); + + /* one endpoint writes data back IN to the host */ + ep = loop->in_ep; + result = usb_ep_enable(ep, src); + if (result < 0) + return result; + ep->driver_data = loop; + + /* one endpoint just reads OUT packets */ + ep = loop->out_ep; + result = usb_ep_enable(ep, sink); + if (result < 0) { +fail0: + ep = loop->in_ep; + usb_ep_disable(ep); + ep->driver_data = NULL; + return result; + } + ep->driver_data = loop; + + /* allocate a bunch of read buffers and queue them all at once. + * we buffer at most 'qlen' transfers; fewer if any need more + * than 'buflen' bytes each. + */ + for (i = 0; i < qlen && result == 0; i++) { + req = alloc_ep_req(ep); + if (req) { + req->complete = loopback_complete; + result = usb_ep_queue(ep, req, GFP_ATOMIC); + if (result) + ERROR(cdev, "%s queue req --> %d\n", + ep->name, result); + } else { + usb_ep_disable(ep); + ep->driver_data = NULL; + result = -ENOMEM; + goto fail0; + } + } + + DBG(cdev, "%s enabled\n", loop->function.name); + return result; +} + +static int loopback_set_alt(struct usb_function *f, + unsigned intf, unsigned alt) +{ + struct f_loopback *loop = func_to_loop(f); + struct usb_composite_dev *cdev = f->config->cdev; + + /* we know alt is zero */ + if (loop->in_ep->driver_data) + disable_loopback(loop); + return enable_loopback(cdev, loop); +} + +static void loopback_disable(struct usb_function *f) +{ + struct f_loopback *loop = func_to_loop(f); + + disable_loopback(loop); +} + +/*-------------------------------------------------------------------------*/ + +static int __init loopback_bind_config(struct usb_configuration *c) +{ + struct f_loopback *loop; + int status; + + loop = kzalloc(sizeof *loop, GFP_KERNEL); + if (!loop) + return -ENOMEM; + + loop->function.name = "loopback"; + loop->function.descriptors = fs_loopback_descs; + loop->function.bind = loopback_bind; + loop->function.unbind = loopback_unbind; + loop->function.set_alt = loopback_set_alt; + loop->function.disable = loopback_disable; + + status = usb_add_function(c, &loop->function); + if (status) + kfree(loop); + return status; +} + +static struct usb_configuration loopback_driver = { + .label = "loopback", + .strings = loopback_strings, + .bind = loopback_bind_config, + .bConfigurationValue = 2, + .bmAttributes = USB_CONFIG_ATT_SELFPOWER, + .bMaxPower = 1, /* 2 mA, minimal */ + /* .iConfiguration = DYNAMIC */ +}; + +/** + * loopback_add - add a loopback testing configuration to a device + * @cdev: the device to support the loopback configuration + */ +int __init loopback_add(struct usb_composite_dev *cdev) +{ + int id; + + /* allocate string ID(s) */ + id = usb_string_id(cdev); + if (id < 0) + return id; + strings_loopback[0].id = id; + + loopback_intf.iInterface = id; + loopback_driver.iConfiguration = id; + + /* support OTG systems */ + if (gadget_is_otg(cdev->gadget)) { + loopback_driver.descriptors = otg_desc; + loopback_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP; + } + + return usb_add_config(cdev, &loopback_driver); +} diff --git a/drivers/usb/gadget/g_zero.h b/drivers/usb/gadget/g_zero.h index 2781221b946..dd2f16ad5a8 100644 --- a/drivers/usb/gadget/g_zero.h +++ b/drivers/usb/gadget/g_zero.h @@ -9,6 +9,7 @@ #include <linux/usb/composite.h> /* global state */ +extern unsigned buflen; extern const struct usb_descriptor_header *otg_desc[]; /* common utilities */ @@ -19,5 +20,6 @@ void disable_endpoints(struct usb_composite_dev *cdev, /* configuration-specific linkup */ int sourcesink_add(struct usb_composite_dev *cdev); +int loopback_add(struct usb_composite_dev *cdev); #endif /* __G_ZERO_H */ |