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 { }, /* set dynamically based on module param */
129 { } /* end of list */
132 #ifdef CONFIG_USB_FUNCTIONFS_GENERIC
133 static char *generic_ffs_config_str = "FunctionFS";
134 module_param_named(generic_ffs_config_str,
135 generic_ffs_config_str,
137 MODULE_PARM_DESC(generic_ffs_config_str,
138 "Configuration string of generic FFS config");
140 static struct usb_gadget_strings *gfs_dev_strings[] = {
141 &(struct usb_gadget_strings) {
142 .language = 0x0409, /* en-us */
143 .strings = gfs_strings,
148 struct gfs_configuration {
149 struct usb_configuration c;
150 int (*eth)(struct usb_configuration *c, u8 *ethaddr,
151 struct eth_dev *dev);
152 } gfs_configurations[] = {
153 #ifdef CONFIG_USB_FUNCTIONFS_RNDIS
155 .eth = rndis_bind_config,
159 #ifdef CONFIG_USB_FUNCTIONFS_ETH
161 .eth = eth_bind_config,
165 #ifdef CONFIG_USB_FUNCTIONFS_GENERIC
171 static int gfs_bind(struct usb_composite_dev *cdev);
172 static int gfs_unbind(struct usb_composite_dev *cdev);
173 static int gfs_do_config(struct usb_configuration *c);
175 static __refdata struct usb_composite_driver gfs_driver = {
177 .dev = &gfs_dev_desc,
178 .strings = gfs_dev_strings,
179 .max_speed = USB_SPEED_HIGH,
181 .unbind = gfs_unbind,
184 static DEFINE_MUTEX(gfs_lock);
185 static unsigned int missing_funcs;
186 static bool gfs_ether_setup;
187 static bool gfs_registered;
188 static bool gfs_single_func;
189 static struct gfs_ffs_obj *ffs_tab;
191 static int __init gfs_init(void)
197 #ifdef CONFIG_USB_FUNCTIONFS_GENERIC
198 /* Find first (but not last) config with a NULL str */
199 for (i = 0; i < ARRAY_SIZE(gfs_strings) - 1 ; ++i)
200 if (!gfs_strings[i].s) {
201 gfs_strings[i].s = generic_ffs_config_str;
206 gfs_single_func = true;
210 ffs_tab = kcalloc(func_num, sizeof *ffs_tab, GFP_KERNEL);
214 if (!gfs_single_func)
215 for (i = 0; i < func_num; i++)
216 ffs_tab[i].name = func_names[i];
218 missing_funcs = func_num;
220 return functionfs_init();
222 module_init(gfs_init);
224 static void __exit gfs_exit(void)
227 mutex_lock(&gfs_lock);
230 usb_composite_unregister(&gfs_driver);
231 gfs_registered = false;
233 functionfs_cleanup();
235 mutex_unlock(&gfs_lock);
238 module_exit(gfs_exit);
240 static struct gfs_ffs_obj *gfs_find_dev(const char *dev_name)
249 for (i = 0; i < func_num; i++)
250 if (strcmp(ffs_tab[i].name, dev_name) == 0)
256 static int functionfs_ready_callback(struct ffs_data *ffs)
258 struct gfs_ffs_obj *ffs_obj;
262 mutex_lock(&gfs_lock);
264 ffs_obj = ffs->private_data;
270 if (WARN_ON(ffs_obj->desc_ready)) {
274 ffs_obj->desc_ready = true;
275 ffs_obj->ffs_data = ffs;
277 if (--missing_funcs) {
282 if (gfs_registered) {
286 gfs_registered = true;
288 ret = usb_composite_probe(&gfs_driver);
289 if (unlikely(ret < 0))
290 gfs_registered = false;
293 mutex_unlock(&gfs_lock);
297 static void functionfs_closed_callback(struct ffs_data *ffs)
299 struct gfs_ffs_obj *ffs_obj;
302 mutex_lock(&gfs_lock);
304 ffs_obj = ffs->private_data;
308 ffs_obj->desc_ready = false;
312 usb_composite_unregister(&gfs_driver);
313 gfs_registered = false;
316 mutex_unlock(&gfs_lock);
319 static void *functionfs_acquire_dev_callback(const char *dev_name)
321 struct gfs_ffs_obj *ffs_dev;
324 mutex_lock(&gfs_lock);
326 ffs_dev = gfs_find_dev(dev_name);
328 ffs_dev = ERR_PTR(-ENODEV);
332 if (ffs_dev->mounted) {
333 ffs_dev = ERR_PTR(-EBUSY);
336 ffs_dev->mounted = true;
339 mutex_unlock(&gfs_lock);
343 static void functionfs_release_dev_callback(struct ffs_data *ffs_data)
345 struct gfs_ffs_obj *ffs_dev;
348 mutex_lock(&gfs_lock);
350 ffs_dev = ffs_data->private_data;
352 ffs_dev->mounted = false;
354 mutex_unlock(&gfs_lock);
358 * It is assumed that gfs_bind is called from a context where gfs_lock is held
360 static int gfs_bind(struct usb_composite_dev *cdev)
368 #if defined CONFIG_USB_FUNCTIONFS_ETH || defined CONFIG_USB_FUNCTIONFS_RNDIS
369 the_dev = gether_setup(cdev->gadget, gfs_hostaddr);
371 if (IS_ERR(the_dev)) {
372 ret = PTR_ERR(the_dev);
375 gfs_ether_setup = true;
377 ret = usb_string_ids_tab(cdev, gfs_strings);
378 if (unlikely(ret < 0))
380 gfs_dev_desc.iProduct = gfs_strings[USB_GADGET_PRODUCT_IDX].id;
382 for (i = func_num; i--; ) {
383 ret = functionfs_bind(ffs_tab[i].ffs_data, cdev);
384 if (unlikely(ret < 0)) {
385 while (++i < func_num)
386 functionfs_unbind(ffs_tab[i].ffs_data);
391 for (i = 0; i < ARRAY_SIZE(gfs_configurations); ++i) {
392 struct gfs_configuration *c = gfs_configurations + i;
393 int sid = USB_GADGET_FIRST_AVAIL_IDX + i;
395 c->c.label = gfs_strings[sid].s;
396 c->c.iConfiguration = gfs_strings[sid].id;
397 c->c.bConfigurationValue = 1 + i;
398 c->c.bmAttributes = USB_CONFIG_ATT_SELFPOWER;
400 ret = usb_add_config(cdev, &c->c, gfs_do_config);
401 if (unlikely(ret < 0))
404 usb_composite_overwrite_options(cdev, &coverwrite);
408 for (i = 0; i < func_num; i++)
409 functionfs_unbind(ffs_tab[i].ffs_data);
411 gether_cleanup(the_dev);
413 gfs_ether_setup = false;
418 * It is assumed that gfs_unbind is called from a context where gfs_lock is held
420 static int gfs_unbind(struct usb_composite_dev *cdev)
427 * We may have been called in an error recovery from
428 * composite_bind() after gfs_unbind() failure so we need to
429 * check if gfs_ffs_data is not NULL since gfs_bind() handles
430 * all error recovery itself. I'd rather we werent called
431 * from composite on orror recovery, but what you're gonna
435 gether_cleanup(the_dev);
436 gfs_ether_setup = false;
438 for (i = func_num; i--; )
439 if (ffs_tab[i].ffs_data)
440 functionfs_unbind(ffs_tab[i].ffs_data);
446 * It is assumed that gfs_do_config is called from a context where
449 static int gfs_do_config(struct usb_configuration *c)
451 struct gfs_configuration *gc =
452 container_of(c, struct gfs_configuration, c);
459 if (gadget_is_otg(c->cdev->gadget)) {
460 c->descriptors = gfs_otg_desc;
461 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
465 ret = gc->eth(c, gfs_hostaddr, the_dev);
466 if (unlikely(ret < 0))
470 for (i = 0; i < func_num; i++) {
471 ret = functionfs_bind_config(c->cdev, c, ffs_tab[i].ffs_data);
472 if (unlikely(ret < 0))
477 * After previous do_configs there may be some invalid
478 * pointers in c->interface array. This happens every time
479 * a user space function with fewer interfaces than a user
480 * space function that was run before the new one is run. The
481 * compasit's set_config() assumes that if there is no more
482 * then MAX_CONFIG_INTERFACES interfaces in a configuration
483 * then there is a NULL pointer after the last interface in
484 * c->interface array. We need to make sure this is true.
486 if (c->next_interface_id < ARRAY_SIZE(c->interface))
487 c->interface[c->next_interface_id] = NULL;
492 #ifdef CONFIG_USB_FUNCTIONFS_ETH
494 static int eth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN],
497 return can_support_ecm(c->cdev->gadget)
498 ? ecm_bind_config(c, ethaddr, dev)
499 : geth_bind_config(c, ethaddr, dev);