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");
141 static int bmAttrs_overwrite = -1;
143 module_param_named(bmAttrs_overwrite, bmAttrs_overwrite, int, 0644);
144 MODULE_PARM_DESC(bmAttrs_overwrite,
145 "Overwrite default bmAttrributes value. -1 to use default.");
147 static struct usb_gadget_strings *gfs_dev_strings[] = {
148 &(struct usb_gadget_strings) {
149 .language = 0x0409, /* en-us */
150 .strings = gfs_strings,
155 struct gfs_configuration {
156 struct usb_configuration c;
157 int (*eth)(struct usb_configuration *c, u8 *ethaddr,
158 struct eth_dev *dev);
159 } gfs_configurations[] = {
160 #ifdef CONFIG_USB_FUNCTIONFS_RNDIS
162 .eth = rndis_bind_config,
166 #ifdef CONFIG_USB_FUNCTIONFS_ETH
168 .eth = eth_bind_config,
172 #ifdef CONFIG_USB_FUNCTIONFS_GENERIC
178 static int gfs_bind(struct usb_composite_dev *cdev);
179 static int gfs_unbind(struct usb_composite_dev *cdev);
180 static int gfs_do_config(struct usb_configuration *c);
182 static __refdata struct usb_composite_driver gfs_driver = {
184 .dev = &gfs_dev_desc,
185 .strings = gfs_dev_strings,
186 .max_speed = USB_SPEED_HIGH,
188 .unbind = gfs_unbind,
191 static DEFINE_MUTEX(gfs_lock);
192 static unsigned int missing_funcs;
193 static bool gfs_ether_setup;
194 static bool gfs_registered;
195 static bool gfs_single_func;
196 static struct gfs_ffs_obj *ffs_tab;
198 static int __init gfs_init(void)
204 #ifdef CONFIG_USB_FUNCTIONFS_GENERIC
205 /* Find first (but not last) config with a NULL str */
206 for (i = 0; i < ARRAY_SIZE(gfs_strings) - 1 ; ++i)
207 if (!gfs_strings[i].s) {
208 gfs_strings[i].s = generic_ffs_config_str;
212 if (bmAttrs_overwrite > 255) {
213 pr_info("Invalid value of bmAttributes for configs.");
218 gfs_single_func = true;
222 ffs_tab = kcalloc(func_num, sizeof *ffs_tab, GFP_KERNEL);
226 if (!gfs_single_func)
227 for (i = 0; i < func_num; i++)
228 ffs_tab[i].name = func_names[i];
230 missing_funcs = func_num;
232 return functionfs_init();
234 module_init(gfs_init);
236 static void __exit gfs_exit(void)
239 mutex_lock(&gfs_lock);
242 usb_composite_unregister(&gfs_driver);
243 gfs_registered = false;
245 functionfs_cleanup();
247 mutex_unlock(&gfs_lock);
250 module_exit(gfs_exit);
252 static struct gfs_ffs_obj *gfs_find_dev(const char *dev_name)
261 for (i = 0; i < func_num; i++)
262 if (strcmp(ffs_tab[i].name, dev_name) == 0)
268 static int functionfs_ready_callback(struct ffs_data *ffs)
270 struct gfs_ffs_obj *ffs_obj;
274 mutex_lock(&gfs_lock);
276 ffs_obj = ffs->private_data;
282 if (WARN_ON(ffs_obj->desc_ready)) {
286 ffs_obj->desc_ready = true;
287 ffs_obj->ffs_data = ffs;
289 if (--missing_funcs) {
294 if (gfs_registered) {
298 gfs_registered = true;
300 ret = usb_composite_probe(&gfs_driver);
301 if (unlikely(ret < 0))
302 gfs_registered = false;
305 mutex_unlock(&gfs_lock);
309 static void functionfs_closed_callback(struct ffs_data *ffs)
311 struct gfs_ffs_obj *ffs_obj;
314 mutex_lock(&gfs_lock);
316 ffs_obj = ffs->private_data;
320 ffs_obj->desc_ready = false;
324 usb_composite_unregister(&gfs_driver);
325 gfs_registered = false;
328 mutex_unlock(&gfs_lock);
331 static void *functionfs_acquire_dev_callback(const char *dev_name)
333 struct gfs_ffs_obj *ffs_dev;
336 mutex_lock(&gfs_lock);
338 ffs_dev = gfs_find_dev(dev_name);
340 ffs_dev = ERR_PTR(-ENODEV);
344 if (ffs_dev->mounted) {
345 ffs_dev = ERR_PTR(-EBUSY);
348 ffs_dev->mounted = true;
351 mutex_unlock(&gfs_lock);
355 static void functionfs_release_dev_callback(struct ffs_data *ffs_data)
357 struct gfs_ffs_obj *ffs_dev;
360 mutex_lock(&gfs_lock);
362 ffs_dev = ffs_data->private_data;
364 ffs_dev->mounted = false;
366 mutex_unlock(&gfs_lock);
370 * It is assumed that gfs_bind is called from a context where gfs_lock is held
372 static int gfs_bind(struct usb_composite_dev *cdev)
380 #if defined CONFIG_USB_FUNCTIONFS_ETH || defined CONFIG_USB_FUNCTIONFS_RNDIS
381 the_dev = gether_setup(cdev->gadget, gfs_hostaddr);
383 if (IS_ERR(the_dev)) {
384 ret = PTR_ERR(the_dev);
387 gfs_ether_setup = true;
389 ret = usb_string_ids_tab(cdev, gfs_strings);
390 if (unlikely(ret < 0))
392 gfs_dev_desc.iProduct = gfs_strings[USB_GADGET_PRODUCT_IDX].id;
394 for (i = func_num; i--; ) {
395 ret = functionfs_bind(ffs_tab[i].ffs_data, cdev);
396 if (unlikely(ret < 0)) {
397 while (++i < func_num)
398 functionfs_unbind(ffs_tab[i].ffs_data);
403 for (i = 0; i < ARRAY_SIZE(gfs_configurations); ++i) {
404 struct gfs_configuration *c = gfs_configurations + i;
405 int sid = USB_GADGET_FIRST_AVAIL_IDX + i;
407 c->c.label = gfs_strings[sid].s;
408 c->c.iConfiguration = gfs_strings[sid].id;
409 c->c.bConfigurationValue = 1 + i;
410 c->c.bmAttributes = bmAttrs_overwrite >= 0 ?
411 (unsigned char)bmAttrs_overwrite
412 : USB_CONFIG_ATT_SELFPOWER;
414 ret = usb_add_config(cdev, &c->c, gfs_do_config);
415 if (unlikely(ret < 0))
418 usb_composite_overwrite_options(cdev, &coverwrite);
422 for (i = 0; i < func_num; i++)
423 functionfs_unbind(ffs_tab[i].ffs_data);
425 gether_cleanup(the_dev);
427 gfs_ether_setup = false;
432 * It is assumed that gfs_unbind is called from a context where gfs_lock is held
434 static int gfs_unbind(struct usb_composite_dev *cdev)
441 * We may have been called in an error recovery from
442 * composite_bind() after gfs_unbind() failure so we need to
443 * check if gfs_ffs_data is not NULL since gfs_bind() handles
444 * all error recovery itself. I'd rather we werent called
445 * from composite on orror recovery, but what you're gonna
449 gether_cleanup(the_dev);
450 gfs_ether_setup = false;
452 for (i = func_num; i--; )
453 if (ffs_tab[i].ffs_data)
454 functionfs_unbind(ffs_tab[i].ffs_data);
460 * It is assumed that gfs_do_config is called from a context where
463 static int gfs_do_config(struct usb_configuration *c)
465 struct gfs_configuration *gc =
466 container_of(c, struct gfs_configuration, c);
473 if (gadget_is_otg(c->cdev->gadget) && bmAttrs_overwrite < 0) {
474 c->descriptors = gfs_otg_desc;
475 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
479 ret = gc->eth(c, gfs_hostaddr, the_dev);
480 if (unlikely(ret < 0))
484 for (i = 0; i < func_num; i++) {
485 ret = functionfs_bind_config(c->cdev, c, ffs_tab[i].ffs_data);
486 if (unlikely(ret < 0))
491 * After previous do_configs there may be some invalid
492 * pointers in c->interface array. This happens every time
493 * a user space function with fewer interfaces than a user
494 * space function that was run before the new one is run. The
495 * compasit's set_config() assumes that if there is no more
496 * then MAX_CONFIG_INTERFACES interfaces in a configuration
497 * then there is a NULL pointer after the last interface in
498 * c->interface array. We need to make sure this is true.
500 if (c->next_interface_id < ARRAY_SIZE(c->interface))
501 c->interface[c->next_interface_id] = NULL;
506 #ifdef CONFIG_USB_FUNCTIONFS_ETH
508 static int eth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN],
511 return can_support_ecm(c->cdev->gadget)
512 ? ecm_bind_config(c, ethaddr, dev)
513 : geth_bind_config(c, ethaddr, dev);