1 /*
2 * g_ffs.c -- user mode file system API for USB composite function controllers
3 *
4 * Copyright (C) 2010 Samsung Electronics
5 * Author: Michal Nazarewicz <m.nazarewicz@samsung.com>
6 *
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.
11 */
12
13 #define pr_fmt(fmt) "g_ffs: " fmt
14
15 #include <linux/module.h>
16 #include <linux/utsname.h>
17
18 /*
19 * kbuild is not very cooperative with respect to linking separately
20 * compiled library objects into one module. So for now we won't use
21 * separate compilation ... ensuring init/exit sections work to shrink
22 * the runtime footprint, and giving us at least some parts of what
23 * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
24 */
25
26 #include "composite.c"
27 #include "usbstring.c"
28 #include "config.c"
29 #include "epautoconf.c"
30
31 #if defined CONFIG_USB_FUNCTIONFS_ETH || defined CONFIG_USB_FUNCTIONFS_RNDIS
32 # if defined USB_ETH_RNDIS
33 # undef USB_ETH_RNDIS
34 # endif
35 # ifdef CONFIG_USB_FUNCTIONFS_RNDIS
36 # define USB_ETH_RNDIS y
37 # endif
38
39 # include "f_ecm.c"
40 # include "f_subset.c"
41 # ifdef USB_ETH_RNDIS
42 # include "f_rndis.c"
43 # include "rndis.c"
44 # endif
45 # include "u_ether.c"
46
47 static u8 gfs_hostaddr[ETH_ALEN];
48 # ifdef CONFIG_USB_FUNCTIONFS_ETH
49 static int eth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]);
50 # endif
51 #else
52 # define gether_cleanup() do { } while (0)
53 # define gether_setup(gadget, hostaddr) ((int)0)
54 # define gfs_hostaddr NULL
55 #endif
56
57 #include "f_fs.c"
58
59 #define DRIVER_NAME "g_ffs"
60 #define DRIVER_DESC "USB Function Filesystem"
61 #define DRIVER_VERSION "24 Aug 2004"
62
63 MODULE_DESCRIPTION(DRIVER_DESC);
64 MODULE_AUTHOR("Michal Nazarewicz");
65 MODULE_LICENSE("GPL");
66
67 #define GFS_VENDOR_ID 0x1d6b /* Linux Foundation */
68 #define GFS_PRODUCT_ID 0x0105 /* FunctionFS Gadget */
69
70 static struct usb_device_descriptor gfs_dev_desc = {
71 .bLength = sizeof gfs_dev_desc,
72 .bDescriptorType = USB_DT_DEVICE,
73
74 .bcdUSB = cpu_to_le16(0x0200),
75 .bDeviceClass = USB_CLASS_PER_INTERFACE,
76
77 .idVendor = cpu_to_le16(GFS_VENDOR_ID),
78 .idProduct = cpu_to_le16(GFS_PRODUCT_ID),
79 };
80
81 module_param_named(bDeviceClass, gfs_dev_desc.bDeviceClass, byte, 0644);
82 MODULE_PARM_DESC(bDeviceClass, "USB Device class");
83 module_param_named(bDeviceSubClass, gfs_dev_desc.bDeviceSubClass, byte, 0644);
84 MODULE_PARM_DESC(bDeviceSubClass, "USB Device subclass");
85 module_param_named(bDeviceProtocol, gfs_dev_desc.bDeviceProtocol, byte, 0644);
86 MODULE_PARM_DESC(bDeviceProtocol, "USB Device protocol");
87
88 static const struct usb_descriptor_header *gfs_otg_desc[] = {
89 (const struct usb_descriptor_header *)
90 &(const struct usb_otg_descriptor) {
91 .bLength = sizeof(struct usb_otg_descriptor),
92 .bDescriptorType = USB_DT_OTG,
93
94 /*
95 * REVISIT SRP-only hardware is possible, although
96 * it would not be called "OTG" ...
97 */
98 .bmAttributes = USB_OTG_SRP | USB_OTG_HNP,
99 },
100
101 NULL
102 };
103
104 /* String IDs are assigned dynamically */
105 static struct usb_string gfs_strings[] = {
106 #ifdef CONFIG_USB_FUNCTIONFS_RNDIS
107 { .s = "FunctionFS + RNDIS" },
108 #endif
109 #ifdef CONFIG_USB_FUNCTIONFS_ETH
110 { .s = "FunctionFS + ECM" },
111 #endif
112 #ifdef CONFIG_USB_FUNCTIONFS_GENERIC
113 { .s = "FunctionFS" },
114 #endif
115 { } /* end of list */
116 };
117
118 static struct usb_gadget_strings *gfs_dev_strings[] = {
119 &(struct usb_gadget_strings) {
120 .language = 0x0409, /* en-us */
121 .strings = gfs_strings,
122 },
123 NULL,
124 };
125
126 struct gfs_configuration {
127 struct usb_configuration c;
128 int (*eth)(struct usb_configuration *c, u8 *ethaddr);
129 } gfs_configurations[] = {
130 #ifdef CONFIG_USB_FUNCTIONFS_RNDIS
131 {
132 .eth = rndis_bind_config,
133 },
134 #endif
135
136 #ifdef CONFIG_USB_FUNCTIONFS_ETH
137 {
138 .eth = eth_bind_config,
139 },
140 #endif
141
142 #ifdef CONFIG_USB_FUNCTIONFS_GENERIC
143 {
144 },
145 #endif
146 };
147
148 static int gfs_bind(struct usb_composite_dev *cdev);
149 static int gfs_unbind(struct usb_composite_dev *cdev);
150 static int gfs_do_config(struct usb_configuration *c);
151
152 static struct usb_composite_driver gfs_driver = {
153 .name = DRIVER_NAME,
154 .dev = &gfs_dev_desc,
155 .strings = gfs_dev_strings,
156 .max_speed = USB_SPEED_HIGH,
157 .unbind = gfs_unbind,
158 .iProduct = DRIVER_DESC,
159 };
160
161 static struct ffs_data *gfs_ffs_data;
162 static unsigned long gfs_registered;
163
gfs_init(void)164 static int gfs_init(void)
165 {
166 ENTER();
167
168 return functionfs_init();
169 }
170 module_init(gfs_init);
171
gfs_exit(void)172 static void gfs_exit(void)
173 {
174 ENTER();
175
176 if (test_and_clear_bit(0, &gfs_registered))
177 usb_composite_unregister(&gfs_driver);
178
179 functionfs_cleanup();
180 }
181 module_exit(gfs_exit);
182
functionfs_ready_callback(struct ffs_data * ffs)183 static int functionfs_ready_callback(struct ffs_data *ffs)
184 {
185 int ret;
186
187 ENTER();
188
189 if (WARN_ON(test_and_set_bit(0, &gfs_registered)))
190 return -EBUSY;
191
192 gfs_ffs_data = ffs;
193 ret = usb_composite_probe(&gfs_driver, gfs_bind);
194 if (unlikely(ret < 0))
195 clear_bit(0, &gfs_registered);
196 return ret;
197 }
198
functionfs_closed_callback(struct ffs_data * ffs)199 static void functionfs_closed_callback(struct ffs_data *ffs)
200 {
201 ENTER();
202
203 if (test_and_clear_bit(0, &gfs_registered))
204 usb_composite_unregister(&gfs_driver);
205 }
206
functionfs_check_dev_callback(const char * dev_name)207 static int functionfs_check_dev_callback(const char *dev_name)
208 {
209 return 0;
210 }
211
gfs_bind(struct usb_composite_dev * cdev)212 static int gfs_bind(struct usb_composite_dev *cdev)
213 {
214 int ret, i;
215
216 ENTER();
217
218 if (WARN_ON(!gfs_ffs_data))
219 return -ENODEV;
220
221 ret = gether_setup(cdev->gadget, gfs_hostaddr);
222 if (unlikely(ret < 0))
223 goto error_quick;
224
225 ret = usb_string_ids_tab(cdev, gfs_strings);
226 if (unlikely(ret < 0))
227 goto error;
228
229 ret = functionfs_bind(gfs_ffs_data, cdev);
230 if (unlikely(ret < 0))
231 goto error;
232
233 for (i = 0; i < ARRAY_SIZE(gfs_configurations); ++i) {
234 struct gfs_configuration *c = gfs_configurations + i;
235
236 c->c.label = gfs_strings[i].s;
237 c->c.iConfiguration = gfs_strings[i].id;
238 c->c.bConfigurationValue = 1 + i;
239 c->c.bmAttributes = USB_CONFIG_ATT_SELFPOWER;
240
241 ret = usb_add_config(cdev, &c->c, gfs_do_config);
242 if (unlikely(ret < 0))
243 goto error_unbind;
244 }
245
246 return 0;
247
248 error_unbind:
249 functionfs_unbind(gfs_ffs_data);
250 error:
251 gether_cleanup();
252 error_quick:
253 gfs_ffs_data = NULL;
254 return ret;
255 }
256
gfs_unbind(struct usb_composite_dev * cdev)257 static int gfs_unbind(struct usb_composite_dev *cdev)
258 {
259 ENTER();
260
261 /*
262 * We may have been called in an error recovery from
263 * composite_bind() after gfs_unbind() failure so we need to
264 * check if gfs_ffs_data is not NULL since gfs_bind() handles
265 * all error recovery itself. I'd rather we werent called
266 * from composite on orror recovery, but what you're gonna
267 * do...?
268 */
269 if (gfs_ffs_data) {
270 gether_cleanup();
271 functionfs_unbind(gfs_ffs_data);
272 gfs_ffs_data = NULL;
273 }
274
275 return 0;
276 }
277
gfs_do_config(struct usb_configuration * c)278 static int gfs_do_config(struct usb_configuration *c)
279 {
280 struct gfs_configuration *gc =
281 container_of(c, struct gfs_configuration, c);
282 int ret;
283
284 if (WARN_ON(!gfs_ffs_data))
285 return -ENODEV;
286
287 if (gadget_is_otg(c->cdev->gadget)) {
288 c->descriptors = gfs_otg_desc;
289 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
290 }
291
292 if (gc->eth) {
293 ret = gc->eth(c, gfs_hostaddr);
294 if (unlikely(ret < 0))
295 return ret;
296 }
297
298 ret = functionfs_bind_config(c->cdev, c, gfs_ffs_data);
299 if (unlikely(ret < 0))
300 return ret;
301
302 /*
303 * After previous do_configs there may be some invalid
304 * pointers in c->interface array. This happens every time
305 * a user space function with fewer interfaces than a user
306 * space function that was run before the new one is run. The
307 * compasit's set_config() assumes that if there is no more
308 * then MAX_CONFIG_INTERFACES interfaces in a configuration
309 * then there is a NULL pointer after the last interface in
310 * c->interface array. We need to make sure this is true.
311 */
312 if (c->next_interface_id < ARRAY_SIZE(c->interface))
313 c->interface[c->next_interface_id] = NULL;
314
315 return 0;
316 }
317
318 #ifdef CONFIG_USB_FUNCTIONFS_ETH
319
eth_bind_config(struct usb_configuration * c,u8 ethaddr[ETH_ALEN])320 static int eth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN])
321 {
322 return can_support_ecm(c->cdev->gadget)
323 ? ecm_bind_config(c, ethaddr)
324 : geth_bind_config(c, ethaddr);
325 }
326
327 #endif
328