linux/drivers/usb/gadget/f_obex.c
David Brownell 2121427836 usb gadget: defer obex enumeration
Some USB peripheral controller drivers support software control
over the data pullup.  Use those controls to prevent the OBEX
function from enumerating until the userspace server has opened
the /dev/ttyGS* node it will use to implement protocol chitchat
with the USB host.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-17 14:40:53 -07:00

494 lines
13 KiB
C

/*
* f_obex.c -- USB CDC OBEX function driver
*
* Copyright (C) 2008 Nokia Corporation
* Contact: Felipe Balbi <felipe.balbi@nokia.com>
*
* Based on f_acm.c by Al Borchers and 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
*/
/* #define VERBOSE_DEBUG */
#include <linux/kernel.h>
#include <linux/utsname.h>
#include <linux/device.h>
#include "u_serial.h"
#include "gadget_chips.h"
/*
* This CDC OBEX function support just packages a TTY-ish byte stream.
* A user mode server will put it into "raw" mode and handle all the
* relevant protocol details ... this is just a kernel passthrough.
* When possible, we prevent gadget enumeration until that server is
* ready to handle the commands.
*/
struct obex_ep_descs {
struct usb_endpoint_descriptor *obex_in;
struct usb_endpoint_descriptor *obex_out;
};
struct f_obex {
struct gserial port;
u8 ctrl_id;
u8 data_id;
u8 port_num;
u8 can_activate;
struct obex_ep_descs fs;
struct obex_ep_descs hs;
};
static inline struct f_obex *func_to_obex(struct usb_function *f)
{
return container_of(f, struct f_obex, port.func);
}
static inline struct f_obex *port_to_obex(struct gserial *p)
{
return container_of(p, struct f_obex, port);
}
/*-------------------------------------------------------------------------*/
#define OBEX_CTRL_IDX 0
#define OBEX_DATA_IDX 1
static struct usb_string obex_string_defs[] = {
[OBEX_CTRL_IDX].s = "CDC Object Exchange (OBEX)",
[OBEX_DATA_IDX].s = "CDC OBEX Data",
{ }, /* end of list */
};
static struct usb_gadget_strings obex_string_table = {
.language = 0x0409, /* en-US */
.strings = obex_string_defs,
};
static struct usb_gadget_strings *obex_strings[] = {
&obex_string_table,
NULL,
};
/*-------------------------------------------------------------------------*/
static struct usb_interface_descriptor obex_control_intf __initdata = {
.bLength = sizeof(obex_control_intf),
.bDescriptorType = USB_DT_INTERFACE,
.bInterfaceNumber = 0,
.bAlternateSetting = 0,
.bNumEndpoints = 0,
.bInterfaceClass = USB_CLASS_COMM,
.bInterfaceSubClass = USB_CDC_SUBCLASS_OBEX,
};
static struct usb_interface_descriptor obex_data_nop_intf __initdata = {
.bLength = sizeof(obex_data_nop_intf),
.bDescriptorType = USB_DT_INTERFACE,
.bInterfaceNumber = 1,
.bAlternateSetting = 0,
.bNumEndpoints = 0,
.bInterfaceClass = USB_CLASS_CDC_DATA,
};
static struct usb_interface_descriptor obex_data_intf __initdata = {
.bLength = sizeof(obex_data_intf),
.bDescriptorType = USB_DT_INTERFACE,
.bInterfaceNumber = 2,
.bAlternateSetting = 1,
.bNumEndpoints = 2,
.bInterfaceClass = USB_CLASS_CDC_DATA,
};
static struct usb_cdc_header_desc obex_cdc_header_desc __initdata = {
.bLength = sizeof(obex_cdc_header_desc),
.bDescriptorType = USB_DT_CS_INTERFACE,
.bDescriptorSubType = USB_CDC_HEADER_TYPE,
.bcdCDC = __constant_cpu_to_le16(0x0120),
};
static struct usb_cdc_union_desc obex_cdc_union_desc __initdata = {
.bLength = sizeof(obex_cdc_union_desc),
.bDescriptorType = USB_DT_CS_INTERFACE,
.bDescriptorSubType = USB_CDC_UNION_TYPE,
.bMasterInterface0 = 1,
.bSlaveInterface0 = 2,
};
static struct usb_cdc_obex_desc obex_desc __initdata = {
.bLength = sizeof(obex_desc),
.bDescriptorType = USB_DT_CS_INTERFACE,
.bDescriptorSubType = USB_CDC_OBEX_TYPE,
.bcdVersion = __constant_cpu_to_le16(0x0100),
};
/* High-Speed Support */
static struct usb_endpoint_descriptor obex_hs_ep_out_desc __initdata = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = __constant_cpu_to_le16(512),
};
static struct usb_endpoint_descriptor obex_hs_ep_in_desc __initdata = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = __constant_cpu_to_le16(512),
};
static struct usb_descriptor_header *hs_function[] __initdata = {
(struct usb_descriptor_header *) &obex_control_intf,
(struct usb_descriptor_header *) &obex_cdc_header_desc,
(struct usb_descriptor_header *) &obex_desc,
(struct usb_descriptor_header *) &obex_cdc_union_desc,
(struct usb_descriptor_header *) &obex_data_nop_intf,
(struct usb_descriptor_header *) &obex_data_intf,
(struct usb_descriptor_header *) &obex_hs_ep_in_desc,
(struct usb_descriptor_header *) &obex_hs_ep_out_desc,
NULL,
};
/* Full-Speed Support */
static struct usb_endpoint_descriptor obex_fs_ep_in_desc __initdata = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
};
static struct usb_endpoint_descriptor obex_fs_ep_out_desc __initdata = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
};
static struct usb_descriptor_header *fs_function[] __initdata = {
(struct usb_descriptor_header *) &obex_control_intf,
(struct usb_descriptor_header *) &obex_cdc_header_desc,
(struct usb_descriptor_header *) &obex_desc,
(struct usb_descriptor_header *) &obex_cdc_union_desc,
(struct usb_descriptor_header *) &obex_data_nop_intf,
(struct usb_descriptor_header *) &obex_data_intf,
(struct usb_descriptor_header *) &obex_fs_ep_in_desc,
(struct usb_descriptor_header *) &obex_fs_ep_out_desc,
NULL,
};
/*-------------------------------------------------------------------------*/
static int obex_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
{
struct f_obex *obex = func_to_obex(f);
struct usb_composite_dev *cdev = f->config->cdev;
if (intf == obex->ctrl_id) {
if (alt != 0)
goto fail;
/* NOP */
DBG(cdev, "reset obex ttyGS%d control\n", obex->port_num);
} else if (intf == obex->data_id) {
if (alt > 1)
goto fail;
if (obex->port.in->driver_data) {
DBG(cdev, "reset obex ttyGS%d\n", obex->port_num);
gserial_disconnect(&obex->port);
}
if (!obex->port.in_desc) {
DBG(cdev, "init obex ttyGS%d\n", obex->port_num);
obex->port.in_desc = ep_choose(cdev->gadget,
obex->hs.obex_in, obex->fs.obex_in);
obex->port.out_desc = ep_choose(cdev->gadget,
obex->hs.obex_out, obex->fs.obex_out);
}
if (alt == 1) {
DBG(cdev, "activate obex ttyGS%d\n", obex->port_num);
gserial_connect(&obex->port, obex->port_num);
}
} else
goto fail;
return 0;
fail:
return -EINVAL;
}
static int obex_get_alt(struct usb_function *f, unsigned intf)
{
struct f_obex *obex = func_to_obex(f);
if (intf == obex->ctrl_id)
return 0;
return obex->port.in->driver_data ? 1 : 0;
}
static void obex_disable(struct usb_function *f)
{
struct f_obex *obex = func_to_obex(f);
struct usb_composite_dev *cdev = f->config->cdev;
DBG(cdev, "obex ttyGS%d disable\n", obex->port_num);
gserial_disconnect(&obex->port);
}
/*-------------------------------------------------------------------------*/
static void obex_connect(struct gserial *g)
{
struct f_obex *obex = port_to_obex(g);
struct usb_composite_dev *cdev = g->func.config->cdev;
int status;
if (!obex->can_activate)
return;
status = usb_function_activate(&g->func);
if (status)
DBG(cdev, "obex ttyGS%d function activate --> %d\n",
obex->port_num, status);
}
static void obex_disconnect(struct gserial *g)
{
struct f_obex *obex = port_to_obex(g);
struct usb_composite_dev *cdev = g->func.config->cdev;
int status;
if (!obex->can_activate)
return;
status = usb_function_deactivate(&g->func);
if (status)
DBG(cdev, "obex ttyGS%d function deactivate --> %d\n",
obex->port_num, status);
}
/*-------------------------------------------------------------------------*/
static int __init
obex_bind(struct usb_configuration *c, struct usb_function *f)
{
struct usb_composite_dev *cdev = c->cdev;
struct f_obex *obex = func_to_obex(f);
int status;
struct usb_ep *ep;
/* allocate instance-specific interface IDs, and patch descriptors */
status = usb_interface_id(c, f);
if (status < 0)
goto fail;
obex->ctrl_id = status;
obex_control_intf.bInterfaceNumber = status;
obex_cdc_union_desc.bMasterInterface0 = status;
status = usb_interface_id(c, f);
if (status < 0)
goto fail;
obex->data_id = status;
obex_data_nop_intf.bInterfaceNumber = status;
obex_data_intf.bInterfaceNumber = status;
obex_cdc_union_desc.bSlaveInterface0 = status;
/* allocate instance-specific endpoints */
ep = usb_ep_autoconfig(cdev->gadget, &obex_fs_ep_in_desc);
if (!ep)
goto fail;
obex->port.in = ep;
ep->driver_data = cdev; /* claim */
ep = usb_ep_autoconfig(cdev->gadget, &obex_fs_ep_out_desc);
if (!ep)
goto fail;
obex->port.out = ep;
ep->driver_data = cdev; /* claim */
/* copy descriptors, and track endpoint copies */
f->descriptors = usb_copy_descriptors(fs_function);
obex->fs.obex_in = usb_find_endpoint(fs_function,
f->descriptors, &obex_fs_ep_in_desc);
obex->fs.obex_out = usb_find_endpoint(fs_function,
f->descriptors, &obex_fs_ep_out_desc);
/* support all relevant hardware speeds... we expect that when
* hardware is dual speed, all bulk-capable endpoints work at
* both speeds
*/
if (gadget_is_dualspeed(c->cdev->gadget)) {
obex_hs_ep_in_desc.bEndpointAddress =
obex_fs_ep_in_desc.bEndpointAddress;
obex_hs_ep_out_desc.bEndpointAddress =
obex_fs_ep_out_desc.bEndpointAddress;
/* copy descriptors, and track endpoint copies */
f->hs_descriptors = usb_copy_descriptors(hs_function);
obex->hs.obex_in = usb_find_endpoint(hs_function,
f->descriptors, &obex_hs_ep_in_desc);
obex->hs.obex_out = usb_find_endpoint(hs_function,
f->descriptors, &obex_hs_ep_out_desc);
}
/* Avoid letting this gadget enumerate until the userspace
* OBEX server is active.
*/
status = usb_function_deactivate(f);
if (status < 0)
WARNING(cdev, "obex ttyGS%d: can't prevent enumeration, %d\n",
obex->port_num, status);
else
obex->can_activate = true;
DBG(cdev, "obex ttyGS%d: %s speed IN/%s OUT/%s\n",
obex->port_num,
gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
obex->port.in->name, obex->port.out->name);
return 0;
fail:
/* we might as well release our claims on endpoints */
if (obex->port.out)
obex->port.out->driver_data = NULL;
if (obex->port.in)
obex->port.in->driver_data = NULL;
ERROR(cdev, "%s/%p: can't bind, err %d\n", f->name, f, status);
return status;
}
static void
obex_unbind(struct usb_configuration *c, struct usb_function *f)
{
if (gadget_is_dualspeed(c->cdev->gadget))
usb_free_descriptors(f->hs_descriptors);
usb_free_descriptors(f->descriptors);
kfree(func_to_obex(f));
}
/* Some controllers can't support CDC OBEX ... */
static inline bool can_support_obex(struct usb_configuration *c)
{
/* Since the first interface is a NOP, we can ignore the
* issue of multi-interface support on most controllers.
*
* Altsettings are mandatory, however...
*/
if (!gadget_supports_altsettings(c->cdev->gadget))
return false;
/* everything else is *probably* fine ... */
return true;
}
/**
* obex_bind_config - add a CDC OBEX function to a configuration
* @c: the configuration to support the CDC OBEX instance
* @port_num: /dev/ttyGS* port this interface will use
* Context: single threaded during gadget setup
*
* Returns zero on success, else negative errno.
*
* Caller must have called @gserial_setup() with enough ports to
* handle all the ones it binds. Caller is also responsible
* for calling @gserial_cleanup() before module unload.
*/
int __init obex_bind_config(struct usb_configuration *c, u8 port_num)
{
struct f_obex *obex;
int status;
if (!can_support_obex(c))
return -EINVAL;
/* maybe allocate device-global string IDs, and patch descriptors */
if (obex_string_defs[OBEX_CTRL_IDX].id == 0) {
status = usb_string_id(c->cdev);
if (status < 0)
return status;
obex_string_defs[OBEX_CTRL_IDX].id = status;
obex_control_intf.iInterface = status;
status = usb_string_id(c->cdev);
if (status < 0)
return status;
obex_string_defs[OBEX_DATA_IDX].id = status;
obex_data_nop_intf.iInterface =
obex_data_intf.iInterface = status;
}
/* allocate and initialize one new instance */
obex = kzalloc(sizeof *obex, GFP_KERNEL);
if (!obex)
return -ENOMEM;
obex->port_num = port_num;
obex->port.connect = obex_connect;
obex->port.disconnect = obex_disconnect;
obex->port.func.name = "obex";
obex->port.func.strings = obex_strings;
/* descriptors are per-instance copies */
obex->port.func.bind = obex_bind;
obex->port.func.unbind = obex_unbind;
obex->port.func.set_alt = obex_set_alt;
obex->port.func.get_alt = obex_get_alt;
obex->port.func.disable = obex_disable;
status = usb_add_function(c, &obex->port.func);
if (status)
kfree(obex);
return status;
}
MODULE_AUTHOR("Felipe Balbi");
MODULE_LICENSE("GPL");