/*
* g_ffs.c -- user mode file system API for USB composite function controllers
*
* Copyright (C) 2010 Samsung Electronics
* Author: Michal Nazarewicz <mina86@mina86.com>
*
* 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.
*/
#define pr_fmt(fmt) "g_ffs: " fmt
#include <linux/module.h>
#include <linux/utsname.h>
/*
* kbuild is not very cooperative with respect to linking separately
* compiled library objects into one module. So for now we won't use
* separate compilation ... ensuring init/exit sections work to shrink
* the runtime footprint, and giving us at least some parts of what
* a "gcc --combine ... part1.c part2.c part3.c ... " build would.
*/
#include "composite.c"
#include "usbstring.c"
#include "config.c"
#include "epautoconf.c"
#if defined CONFIG_USB_FUNCTIONFS_ETH || defined CONFIG_USB_FUNCTIONFS_RNDIS
# if defined USB_ETH_RNDIS
# undef USB_ETH_RNDIS
# endif
# ifdef CONFIG_USB_FUNCTIONFS_RNDIS
# define USB_ETH_RNDIS y
# endif
# include "f_ecm.c"
# include "f_subset.c"
# ifdef USB_ETH_RNDIS
# include "f_rndis.c"
# include "rndis.c"
# endif
# include "u_ether.c"
static u8 gfs_hostaddr[ETH_ALEN];
# ifdef CONFIG_USB_FUNCTIONFS_ETH
static int eth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]);
# endif
#else
# define gether_cleanup() do { } while (0)
# define gether_setup(gadget, hostaddr) ((int)0)
# define gfs_hostaddr NULL
#endif
#include "f_fs.c"
#define DRIVER_NAME "g_ffs"
#define DRIVER_DESC "USB Function Filesystem"
#define DRIVER_VERSION "24 Aug 2004"
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR("Michal Nazarewicz");
MODULE_LICENSE("GPL");
#define GFS_VENDOR_ID 0x1d6b /* Linux Foundation */
#define GFS_PRODUCT_ID 0x0105 /* FunctionFS Gadget */
#define GFS_MAX_DEVS 10
struct gfs_ffs_obj {
const char *name;
bool mounted;
bool desc_ready;
struct ffs_data *ffs_data;
};
static struct usb_device_descriptor gfs_dev_desc = {
.bLength = sizeof gfs_dev_desc,
.bDescriptorType = USB_DT_DEVICE,
.bcdUSB = cpu_to_le16(0x0200),
.bDeviceClass = USB_CLASS_PER_INTERFACE,
.idVendor = cpu_to_le16(GFS_VENDOR_ID),
.idProduct = cpu_to_le16(GFS_PRODUCT_ID),
};
static char *func_names[GFS_MAX_DEVS];
static unsigned int func_num;
module_param_named(bDeviceClass, gfs_dev_desc.bDeviceClass, byte, 0644);
MODULE_PARM_DESC(bDeviceClass, "USB Device class");
module_param_named(bDeviceSubClass, gfs_dev_desc.bDeviceSubClass, byte, 0644);
MODULE_PARM_DESC(bDeviceSubClass, "USB Device subclass");
module_param_named(bDeviceProtocol, gfs_dev_desc.bDeviceProtocol, byte, 0644);
MODULE_PARM_DESC(bDeviceProtocol, "USB Device protocol");
module_param_array_named(functions, func_names, charp, &func_num, 0);
MODULE_PARM_DESC(functions, "USB Functions list");
static const struct usb_descriptor_header *gfs_otg_desc[] = {
(const struct usb_descriptor_header *)
&(const struct usb_otg_descriptor) {
.bLength = sizeof(struct usb_otg_descriptor),
.bDescriptorType = USB_DT_OTG,
/*
* REVISIT SRP-only hardware is possible, although
* it would not be called "OTG" ...
*/
.bmAttributes = USB_OTG_SRP | USB_OTG_HNP,
},
NULL
};
/* String IDs are assigned dynamically */
static struct usb_string gfs_strings[] = {
#ifdef CONFIG_USB_FUNCTIONFS_RNDIS
{ .s = "FunctionFS + RNDIS" },
#endif
#ifdef CONFIG_USB_FUNCTIONFS_ETH
{ .s = "FunctionFS + ECM" },
#endif
#ifdef CONFIG_USB_FUNCTIONFS_GENERIC
{ .s = "FunctionFS" },
#endif
{ } /* end of list */
};
static struct usb_gadget_strings *gfs_dev_strings[] = {
&(struct usb_gadget_strings) {
.language = 0x0409, /* en-us */
.strings = gfs_strings,
},
NULL,
};
struct gfs_configuration {
struct usb_configuration c;
int (*eth)(struct usb_configuration *c, u8 *ethaddr);
} gfs_configurations[] = {
#ifdef CONFIG_USB_FUNCTIONFS_RNDIS
{
.eth = rndis_bind_config,
},
#endif
#ifdef CONFIG_USB_FUNCTIONFS_ETH
{
.eth = eth_bind_config,
},
#endif
#ifdef CONFIG_USB_FUNCTIONFS_GENERIC
{
},
#endif
};
static int gfs_bind(struct usb_composite_dev *cdev);
static int gfs_unbind(struct usb_composite_dev *cdev);
static int gfs_do_config(struct usb_configuration *c);
static struct usb_composite_driver gfs_driver = {
.name = DRIVER_NAME,
.dev = &gfs_dev_desc,
.strings = gfs_dev_strings,
.max_speed = USB_SPEED_HIGH,
.unbind = gfs_unbind,
.iProduct = DRIVER_DESC,
};
static DEFINE_MUTEX(gfs_lock);
static unsigned int missing_funcs;
static bool gfs_ether_setup;
static bool gfs_registered;
static bool gfs_single_func;
static struct gfs_ffs_obj *ffs_tab;
static int __init gfs_init(void)
{
int i;
ENTER();
if (!func_num) {
gfs_single_func = true;
func_num = 1;
}
ffs_tab = kcalloc(func_num, sizeof *ffs_tab, GFP_KERNEL);
if (!ffs_tab)
return -ENOMEM;
if (!gfs_single_func)
for (i = 0; i < func_num; i++)
ffs_tab[i].name = func_names[i];
missing_funcs = func_num;
return functionfs_init();
}
module_init(gfs_init);
static void __exit gfs_exit(void)
{
ENTER();
mutex_lock(&gfs_lock);
if (gfs_registered)
usb_composite_unregister(&gfs_driver);
gfs_registered = false;
functionfs_cleanup();
mutex_unlock(&gfs_lock);
kfree(ffs_tab);
}
module_exit(gfs_exit);
static struct gfs_ffs_obj *gfs_find_dev(const char *dev_name)
{
int i;
ENTER();
if (gfs_single_func)
return &ffs_tab[0];
for (i = 0; i < func_num; i++)
if (strcmp(ffs_tab[i].name, dev_name) == 0)
return &ffs_tab[i];
return NULL;
}
static int functionfs_ready_callback(struct ffs_data *ffs)
{
struct gfs_ffs_obj *ffs_obj;
int ret;
ENTER();
mutex_lock(&gfs_lock);
ffs_obj = ffs->private_data;
if (!ffs_obj) {
ret = -EINVAL;
goto done;
}
if (WARN_ON(ffs_obj->desc_ready)) {
ret = -EBUSY;
goto done;
}
ffs_obj->desc_ready = true;
ffs_obj->ffs_data = ffs;
if (--missing_funcs) {
ret = 0;
goto done;
}
if (gfs_registered) {
ret = -EBUSY;
goto done;
}
gfs_registered = true;
ret = usb_composite_probe(&gfs_driver, gfs_bind);
if (unlikely(ret < 0))
gfs_registered = false;
done:
mutex_unlock(&gfs_lock);
return ret;
}
static void functionfs_closed_callback(struct ffs_data *ffs)
{
struct gfs_ffs_obj *ffs_obj;
ENTER();
mutex_lock(&gfs_lock);
ffs_obj = ffs->private_data;
if (!ffs_obj)
goto done;
ffs_obj->desc_ready = false;
missing_funcs++;
if (gfs_registered)
usb_composite_unregister(&gfs_driver);
gfs_registered = false;
done:
mutex_unlock(&gfs_lock);
}
static void *functionfs_acquire_dev_callback(const char *dev_name)
{
struct gfs_ffs_obj *ffs_dev;
ENTER();
mutex_lock(&gfs_lock);
ffs_dev = gfs_find_dev(dev_name);
if (!ffs_dev) {
ffs_dev = ERR_PTR(-ENODEV);
goto done;
}
if (ffs_dev->mounted) {
ffs_dev = ERR_PTR(-EBUSY);
goto done;
}
ffs_dev->mounted = true;
done:
mutex_unlock(&gfs_lock);
return ffs_dev;
}
static void functionfs_release_dev_callback(struct ffs_data *ffs_data)
{
struct gfs_ffs_obj *ffs_dev;
ENTER();
mutex_lock(&gfs_lock);
ffs_dev = ffs_data->private_data;
if (ffs_dev)
ffs_dev->mounted = false;
mutex_unlock(&gfs_lock);
}
/*
* It is assumed that gfs_bind is called from a context where gfs_lock is held
*/
static int gfs_bind(struct usb_composite_dev *cdev)
{
int ret, i;
ENTER();
if (missing_funcs)
return -ENODEV;
ret = gether_setup(cdev->gadget, gfs_hostaddr);
if (unlikely(ret < 0))
goto error_quick;
gfs_ether_setup = true;
ret = usb_string_ids_tab(cdev, gfs_strings);
if (unlikely(ret < 0))
goto error;
for (i = func_num; --i; ) {
ret = functionfs_bind(ffs_tab[i].ffs_data, cdev);
if (unlikely(ret < 0)) {
while (++i < func_num)
functionfs_unbind(ffs_tab[i].ffs_data);
goto error;
}
}
for (i = 0; i < ARRAY_SIZE(gfs_configurations); ++i) {
struct gfs_configuration *c = gfs_configurations + i;
c->c.label = gfs_strings[i].s;
c->c.iConfiguration = gfs_strings[i].id;
c->c.bConfigurationValue = 1 + i;
c->c.bmAttributes = USB_CONFIG_ATT_SELFPOWER;
ret = usb_add_config(cdev, &c->c, gfs_do_config);
if (unlikely(ret < 0))
goto error_unbind;
}
return 0;
error_unbind:
for (i = 0; i < func_num; i++)
functionfs_unbind(ffs_tab[i].ffs_data);
error:
gether_cleanup();
error_quick:
gfs_ether_setup = false;
return ret;
}
/*
* It is assumed that gfs_unbind is called from a context where gfs_lock is held
*/
static int gfs_unbind(struct usb_composite_dev *cdev)
{
int i;
ENTER();
/*
* We may have been called in an error recovery from
* composite_bind() after gfs_unbind() failure so we need to
* check if gfs_ffs_data is not NULL since gfs_bind() handles
* all error recovery itself. I'd rather we werent called
* from composite on orror recovery, but what you're gonna
* do...?
*/
if (gfs_ether_setup)
gether_cleanup();
gfs_ether_setup = false;
for (i = func_num; --i; )
if (ffs_tab[i].ffs_data)
functionfs_unbind(ffs_tab[i].ffs_data);
return 0;
}
/*
* It is assumed that gfs_do_config is called from a context where
* gfs_lock is held
*/
static int gfs_do_config(struct usb_configuration *c)
{
struct gfs_configuration *gc =
container_of(c, struct gfs_configuration, c);
int i;
int ret;
if (missing_funcs)
return -ENODEV;
if (gadget_is_otg(c->cdev->gadget)) {
c->descriptors = gfs_otg_desc;
c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
}
if (gc->eth) {
ret = gc->eth(c, gfs_hostaddr);
if (unlikely(ret < 0))
return ret;
}
for (i = 0; i < func_num; i++) {
ret = functionfs_bind_config(c->cdev, c, ffs_tab[i].ffs_data);
if (unlikely(ret < 0))
return ret;
}
/*
* After previous do_configs there may be some invalid
* pointers in c->interface array. This happens every time
* a user space function with fewer interfaces than a user
* space function that was run before the new one is run. The
* compasit's set_config() assumes that if there is no more
* then MAX_CONFIG_INTERFACES interfaces in a configuration
* then there is a NULL pointer after the last interface in
* c->interface array. We need to make sure this is true.
*/
if (c->next_interface_id < ARRAY_SIZE(c->interface))
c->interface[c->next_interface_id] = NULL;
return 0;
}
#ifdef CONFIG_USB_FUNCTIONFS_ETH
static int eth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN])
{
return can_support_ecm(c->cdev->gadget)
? ecm_bind_config(c, ethaddr)
: geth_bind_config(c, ethaddr);
}
#endif
