2 * g_ffs.c -- user mode file system API for USB composite function controllers
4 * Copyright (C) 2010 Samsung Electronics
5 * Author: Michal Nazarewicz <mina86@mina86.com>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
13 #define pr_fmt(fmt) "g_ffs: " fmt
15 #include <linux/module.h>
17 * kbuild is not very cooperative with respect to linking separately
18 * compiled library objects into one module. So for now we won't use
19 * separate compilation ... ensuring init/exit sections work to shrink
20 * the runtime footprint, and giving us at least some parts of what
21 * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
23 #if defined CONFIG_USB_FUNCTIONFS_ETH || defined CONFIG_USB_FUNCTIONFS_RNDIS
24 # if defined USB_ETH_RNDIS
27 # ifdef CONFIG_USB_FUNCTIONFS_RNDIS
28 # define USB_ETH_RNDIS y
32 # include "f_subset.c"
39 static u8 gfs_hostaddr[ETH_ALEN];
40 static struct eth_dev *the_dev;
41 # ifdef CONFIG_USB_FUNCTIONFS_ETH
42 static int eth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN],
47 # define gether_cleanup(dev) do { } while (0)
48 # define gfs_hostaddr NULL
54 #define DRIVER_NAME "g_ffs"
55 #define DRIVER_DESC "USB Function Filesystem"
56 #define DRIVER_VERSION "24 Aug 2004"
58 MODULE_DESCRIPTION(DRIVER_DESC);
59 MODULE_AUTHOR("Michal Nazarewicz");
60 MODULE_LICENSE("GPL");
62 #define GFS_VENDOR_ID 0x1d6b /* Linux Foundation */
63 #define GFS_PRODUCT_ID 0x0105 /* FunctionFS Gadget */
65 #define GFS_MAX_DEVS 10
71 struct ffs_data *ffs_data;
74 USB_GADGET_COMPOSITE_OPTIONS();
76 static struct usb_device_descriptor gfs_dev_desc = {
77 .bLength = sizeof gfs_dev_desc,
78 .bDescriptorType = USB_DT_DEVICE,
80 .bcdUSB = cpu_to_le16(0x0200),
81 .bDeviceClass = USB_CLASS_PER_INTERFACE,
83 .idVendor = cpu_to_le16(GFS_VENDOR_ID),
84 .idProduct = cpu_to_le16(GFS_PRODUCT_ID),
87 static char *func_names[GFS_MAX_DEVS];
88 static unsigned int func_num;
90 module_param_named(bDeviceClass, gfs_dev_desc.bDeviceClass, byte, 0644);
91 MODULE_PARM_DESC(bDeviceClass, "USB Device class");
92 module_param_named(bDeviceSubClass, gfs_dev_desc.bDeviceSubClass, byte, 0644);
93 MODULE_PARM_DESC(bDeviceSubClass, "USB Device subclass");
94 module_param_named(bDeviceProtocol, gfs_dev_desc.bDeviceProtocol, byte, 0644);
95 MODULE_PARM_DESC(bDeviceProtocol, "USB Device protocol");
96 module_param_array_named(functions, func_names, charp, &func_num, 0);
97 MODULE_PARM_DESC(functions, "USB Functions list");
99 static const struct usb_descriptor_header *gfs_otg_desc[] = {
100 (const struct usb_descriptor_header *)
101 &(const struct usb_otg_descriptor) {
102 .bLength = sizeof(struct usb_otg_descriptor),
103 .bDescriptorType = USB_DT_OTG,
106 * REVISIT SRP-only hardware is possible, although
107 * it would not be called "OTG" ...
109 .bmAttributes = USB_OTG_SRP | USB_OTG_HNP,
115 /* String IDs are assigned dynamically */
116 static struct usb_string gfs_strings[] = {
117 [USB_GADGET_MANUFACTURER_IDX].s = "",
118 [USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
119 [USB_GADGET_SERIAL_IDX].s = "",
120 #ifdef CONFIG_USB_FUNCTIONFS_RNDIS
121 { .s = "FunctionFS + RNDIS" },
123 #ifdef CONFIG_USB_FUNCTIONFS_ETH
124 { .s = "FunctionFS + ECM" },
126 #ifdef CONFIG_USB_FUNCTIONFS_GENERIC
127 { .s = "FunctionFS" },
129 { } /* end of list */
132 static struct usb_gadget_strings *gfs_dev_strings[] = {
133 &(struct usb_gadget_strings) {
134 .language = 0x0409, /* en-us */
135 .strings = gfs_strings,
140 struct gfs_configuration {
141 struct usb_configuration c;
142 int (*eth)(struct usb_configuration *c, u8 *ethaddr,
143 struct eth_dev *dev);
144 } gfs_configurations[] = {
145 #ifdef CONFIG_USB_FUNCTIONFS_RNDIS
147 .eth = rndis_bind_config,
151 #ifdef CONFIG_USB_FUNCTIONFS_ETH
153 .eth = eth_bind_config,
157 #ifdef CONFIG_USB_FUNCTIONFS_GENERIC
163 static int gfs_bind(struct usb_composite_dev *cdev);
164 static int gfs_unbind(struct usb_composite_dev *cdev);
165 static int gfs_do_config(struct usb_configuration *c);
167 static __refdata struct usb_composite_driver gfs_driver = {
169 .dev = &gfs_dev_desc,
170 .strings = gfs_dev_strings,
171 .max_speed = USB_SPEED_HIGH,
173 .unbind = gfs_unbind,
176 static DEFINE_MUTEX(gfs_lock);
177 static unsigned int missing_funcs;
178 static bool gfs_ether_setup;
179 static bool gfs_registered;
180 static bool gfs_single_func;
181 static struct gfs_ffs_obj *ffs_tab;
183 static int __init gfs_init(void)
190 gfs_single_func = true;
194 ffs_tab = kcalloc(func_num, sizeof *ffs_tab, GFP_KERNEL);
198 if (!gfs_single_func)
199 for (i = 0; i < func_num; i++)
200 ffs_tab[i].name = func_names[i];
202 missing_funcs = func_num;
204 return functionfs_init();
206 module_init(gfs_init);
208 static void __exit gfs_exit(void)
211 mutex_lock(&gfs_lock);
214 usb_composite_unregister(&gfs_driver);
215 gfs_registered = false;
217 functionfs_cleanup();
219 mutex_unlock(&gfs_lock);
222 module_exit(gfs_exit);
224 static struct gfs_ffs_obj *gfs_find_dev(const char *dev_name)
233 for (i = 0; i < func_num; i++)
234 if (strcmp(ffs_tab[i].name, dev_name) == 0)
240 static int functionfs_ready_callback(struct ffs_data *ffs)
242 struct gfs_ffs_obj *ffs_obj;
246 mutex_lock(&gfs_lock);
248 ffs_obj = ffs->private_data;
254 if (WARN_ON(ffs_obj->desc_ready)) {
258 ffs_obj->desc_ready = true;
259 ffs_obj->ffs_data = ffs;
261 if (--missing_funcs) {
266 if (gfs_registered) {
270 gfs_registered = true;
272 ret = usb_composite_probe(&gfs_driver);
273 if (unlikely(ret < 0))
274 gfs_registered = false;
277 mutex_unlock(&gfs_lock);
281 static void functionfs_closed_callback(struct ffs_data *ffs)
283 struct gfs_ffs_obj *ffs_obj;
286 mutex_lock(&gfs_lock);
288 ffs_obj = ffs->private_data;
292 ffs_obj->desc_ready = false;
296 usb_composite_unregister(&gfs_driver);
297 gfs_registered = false;
300 mutex_unlock(&gfs_lock);
303 static void *functionfs_acquire_dev_callback(const char *dev_name)
305 struct gfs_ffs_obj *ffs_dev;
308 mutex_lock(&gfs_lock);
310 ffs_dev = gfs_find_dev(dev_name);
312 ffs_dev = ERR_PTR(-ENODEV);
316 if (ffs_dev->mounted) {
317 ffs_dev = ERR_PTR(-EBUSY);
320 ffs_dev->mounted = true;
323 mutex_unlock(&gfs_lock);
327 static void functionfs_release_dev_callback(struct ffs_data *ffs_data)
329 struct gfs_ffs_obj *ffs_dev;
332 mutex_lock(&gfs_lock);
334 ffs_dev = ffs_data->private_data;
336 ffs_dev->mounted = false;
338 mutex_unlock(&gfs_lock);
342 * It is assumed that gfs_bind is called from a context where gfs_lock is held
344 static int gfs_bind(struct usb_composite_dev *cdev)
352 #if defined CONFIG_USB_FUNCTIONFS_ETH || defined CONFIG_USB_FUNCTIONFS_RNDIS
353 the_dev = gether_setup(cdev->gadget, gfs_hostaddr);
355 if (IS_ERR(the_dev)) {
356 ret = PTR_ERR(the_dev);
359 gfs_ether_setup = true;
361 ret = usb_string_ids_tab(cdev, gfs_strings);
362 if (unlikely(ret < 0))
364 gfs_dev_desc.iProduct = gfs_strings[USB_GADGET_PRODUCT_IDX].id;
366 for (i = func_num; i--; ) {
367 ret = functionfs_bind(ffs_tab[i].ffs_data, cdev);
368 if (unlikely(ret < 0)) {
369 while (++i < func_num)
370 functionfs_unbind(ffs_tab[i].ffs_data);
375 for (i = 0; i < ARRAY_SIZE(gfs_configurations); ++i) {
376 struct gfs_configuration *c = gfs_configurations + i;
377 int sid = USB_GADGET_FIRST_AVAIL_IDX + i;
379 c->c.label = gfs_strings[sid].s;
380 c->c.iConfiguration = gfs_strings[sid].id;
381 c->c.bConfigurationValue = 1 + i;
382 c->c.bmAttributes = USB_CONFIG_ATT_SELFPOWER;
384 ret = usb_add_config(cdev, &c->c, gfs_do_config);
385 if (unlikely(ret < 0))
388 usb_composite_overwrite_options(cdev, &coverwrite);
392 for (i = 0; i < func_num; i++)
393 functionfs_unbind(ffs_tab[i].ffs_data);
395 gether_cleanup(the_dev);
397 gfs_ether_setup = false;
402 * It is assumed that gfs_unbind is called from a context where gfs_lock is held
404 static int gfs_unbind(struct usb_composite_dev *cdev)
411 * We may have been called in an error recovery from
412 * composite_bind() after gfs_unbind() failure so we need to
413 * check if gfs_ffs_data is not NULL since gfs_bind() handles
414 * all error recovery itself. I'd rather we werent called
415 * from composite on orror recovery, but what you're gonna
419 gether_cleanup(the_dev);
420 gfs_ether_setup = false;
422 for (i = func_num; i--; )
423 if (ffs_tab[i].ffs_data)
424 functionfs_unbind(ffs_tab[i].ffs_data);
430 * It is assumed that gfs_do_config is called from a context where
433 static int gfs_do_config(struct usb_configuration *c)
435 struct gfs_configuration *gc =
436 container_of(c, struct gfs_configuration, c);
443 if (gadget_is_otg(c->cdev->gadget)) {
444 c->descriptors = gfs_otg_desc;
445 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
449 ret = gc->eth(c, gfs_hostaddr, the_dev);
450 if (unlikely(ret < 0))
454 for (i = 0; i < func_num; i++) {
455 ret = functionfs_bind_config(c->cdev, c, ffs_tab[i].ffs_data);
456 if (unlikely(ret < 0))
461 * After previous do_configs there may be some invalid
462 * pointers in c->interface array. This happens every time
463 * a user space function with fewer interfaces than a user
464 * space function that was run before the new one is run. The
465 * compasit's set_config() assumes that if there is no more
466 * then MAX_CONFIG_INTERFACES interfaces in a configuration
467 * then there is a NULL pointer after the last interface in
468 * c->interface array. We need to make sure this is true.
470 if (c->next_interface_id < ARRAY_SIZE(c->interface))
471 c->interface[c->next_interface_id] = NULL;
476 #ifdef CONFIG_USB_FUNCTIONFS_ETH
478 static int eth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN],
481 return can_support_ecm(c->cdev->gadget)
482 ? ecm_bind_config(c, ethaddr, dev)
483 : geth_bind_config(c, ethaddr, dev);