Linux 4.2.1
[linux/fpc-iii.git] / drivers / usb / gadget / legacy / mass_storage.c
blobe7bfb081f111e4b60e55bce9ae5cd5f0743dad20
1 /*
2 * mass_storage.c -- Mass Storage USB Gadget
4 * Copyright (C) 2003-2008 Alan Stern
5 * Copyright (C) 2009 Samsung Electronics
6 * Author: Michal Nazarewicz <mina86@mina86.com>
7 * All rights reserved.
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
17 * The Mass Storage Gadget acts as a USB Mass Storage device,
18 * appearing to the host as a disk drive or as a CD-ROM drive. In
19 * addition to providing an example of a genuinely useful gadget
20 * driver for a USB device, it also illustrates a technique of
21 * double-buffering for increased throughput. Last but not least, it
22 * gives an easy way to probe the behavior of the Mass Storage drivers
23 * in a USB host.
25 * Since this file serves only administrative purposes and all the
26 * business logic is implemented in f_mass_storage.* file. Read
27 * comments in this file for more detailed description.
31 #include <linux/kernel.h>
32 #include <linux/usb/ch9.h>
33 #include <linux/module.h>
35 /*-------------------------------------------------------------------------*/
37 #define DRIVER_DESC "Mass Storage Gadget"
38 #define DRIVER_VERSION "2009/09/11"
41 * Thanks to NetChip Technologies for donating this product ID.
43 * DO NOT REUSE THESE IDs with any other driver!! Ever!!
44 * Instead: allocate your own, using normal USB-IF procedures.
46 #define FSG_VENDOR_ID 0x0525 /* NetChip */
47 #define FSG_PRODUCT_ID 0xa4a5 /* Linux-USB File-backed Storage Gadget */
49 #include "f_mass_storage.h"
51 /*-------------------------------------------------------------------------*/
52 USB_GADGET_COMPOSITE_OPTIONS();
54 static struct usb_device_descriptor msg_device_desc = {
55 .bLength = sizeof msg_device_desc,
56 .bDescriptorType = USB_DT_DEVICE,
58 .bcdUSB = cpu_to_le16(0x0200),
59 .bDeviceClass = USB_CLASS_PER_INTERFACE,
61 /* Vendor and product id can be overridden by module parameters. */
62 .idVendor = cpu_to_le16(FSG_VENDOR_ID),
63 .idProduct = cpu_to_le16(FSG_PRODUCT_ID),
64 .bNumConfigurations = 1,
67 static struct usb_otg_descriptor otg_descriptor = {
68 .bLength = sizeof otg_descriptor,
69 .bDescriptorType = USB_DT_OTG,
72 * REVISIT SRP-only hardware is possible, although
73 * it would not be called "OTG" ...
75 .bmAttributes = USB_OTG_SRP | USB_OTG_HNP,
78 static const struct usb_descriptor_header *otg_desc[] = {
79 (struct usb_descriptor_header *) &otg_descriptor,
80 NULL,
83 static struct usb_string strings_dev[] = {
84 [USB_GADGET_MANUFACTURER_IDX].s = "",
85 [USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
86 [USB_GADGET_SERIAL_IDX].s = "",
87 { } /* end of list */
90 static struct usb_gadget_strings stringtab_dev = {
91 .language = 0x0409, /* en-us */
92 .strings = strings_dev,
95 static struct usb_gadget_strings *dev_strings[] = {
96 &stringtab_dev,
97 NULL,
100 static struct usb_function_instance *fi_msg;
101 static struct usb_function *f_msg;
103 /****************************** Configurations ******************************/
105 static struct fsg_module_parameters mod_data = {
106 .stall = 1
108 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
110 static unsigned int fsg_num_buffers = CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS;
112 #else
115 * Number of buffers we will use.
116 * 2 is usually enough for good buffering pipeline
118 #define fsg_num_buffers CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS
120 #endif /* CONFIG_USB_GADGET_DEBUG_FILES */
122 FSG_MODULE_PARAMETERS(/* no prefix */, mod_data);
124 static unsigned long msg_registered;
125 static void msg_cleanup(void);
127 static int msg_thread_exits(struct fsg_common *common)
129 msg_cleanup();
130 return 0;
133 static int msg_do_config(struct usb_configuration *c)
135 struct fsg_opts *opts;
136 int ret;
138 if (gadget_is_otg(c->cdev->gadget)) {
139 c->descriptors = otg_desc;
140 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
143 opts = fsg_opts_from_func_inst(fi_msg);
145 f_msg = usb_get_function(fi_msg);
146 if (IS_ERR(f_msg))
147 return PTR_ERR(f_msg);
149 ret = fsg_common_run_thread(opts->common);
150 if (ret)
151 goto put_func;
153 ret = usb_add_function(c, f_msg);
154 if (ret)
155 goto put_func;
157 return 0;
159 put_func:
160 usb_put_function(f_msg);
161 return ret;
164 static struct usb_configuration msg_config_driver = {
165 .label = "Linux File-Backed Storage",
166 .bConfigurationValue = 1,
167 .bmAttributes = USB_CONFIG_ATT_SELFPOWER,
171 /****************************** Gadget Bind ******************************/
173 static int msg_bind(struct usb_composite_dev *cdev)
175 static const struct fsg_operations ops = {
176 .thread_exits = msg_thread_exits,
178 struct fsg_opts *opts;
179 struct fsg_config config;
180 int status;
182 fi_msg = usb_get_function_instance("mass_storage");
183 if (IS_ERR(fi_msg))
184 return PTR_ERR(fi_msg);
186 fsg_config_from_params(&config, &mod_data, fsg_num_buffers);
187 opts = fsg_opts_from_func_inst(fi_msg);
189 opts->no_configfs = true;
190 status = fsg_common_set_num_buffers(opts->common, fsg_num_buffers);
191 if (status)
192 goto fail;
194 status = fsg_common_set_nluns(opts->common, config.nluns);
195 if (status)
196 goto fail_set_nluns;
198 fsg_common_set_ops(opts->common, &ops);
200 status = fsg_common_set_cdev(opts->common, cdev, config.can_stall);
201 if (status)
202 goto fail_set_cdev;
204 fsg_common_set_sysfs(opts->common, true);
205 status = fsg_common_create_luns(opts->common, &config);
206 if (status)
207 goto fail_set_cdev;
209 fsg_common_set_inquiry_string(opts->common, config.vendor_name,
210 config.product_name);
212 status = usb_string_ids_tab(cdev, strings_dev);
213 if (status < 0)
214 goto fail_string_ids;
215 msg_device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
217 status = usb_add_config(cdev, &msg_config_driver, msg_do_config);
218 if (status < 0)
219 goto fail_string_ids;
221 usb_composite_overwrite_options(cdev, &coverwrite);
222 dev_info(&cdev->gadget->dev,
223 DRIVER_DESC ", version: " DRIVER_VERSION "\n");
224 set_bit(0, &msg_registered);
225 return 0;
227 fail_string_ids:
228 fsg_common_remove_luns(opts->common);
229 fail_set_cdev:
230 fsg_common_free_luns(opts->common);
231 fail_set_nluns:
232 fsg_common_free_buffers(opts->common);
233 fail:
234 usb_put_function_instance(fi_msg);
235 return status;
238 static int msg_unbind(struct usb_composite_dev *cdev)
240 if (!IS_ERR(f_msg))
241 usb_put_function(f_msg);
243 if (!IS_ERR(fi_msg))
244 usb_put_function_instance(fi_msg);
246 return 0;
249 /****************************** Some noise ******************************/
251 static struct usb_composite_driver msg_driver = {
252 .name = "g_mass_storage",
253 .dev = &msg_device_desc,
254 .max_speed = USB_SPEED_SUPER,
255 .needs_serial = 1,
256 .strings = dev_strings,
257 .bind = msg_bind,
258 .unbind = msg_unbind,
261 MODULE_DESCRIPTION(DRIVER_DESC);
262 MODULE_AUTHOR("Michal Nazarewicz");
263 MODULE_LICENSE("GPL");
265 static int __init msg_init(void)
267 return usb_composite_probe(&msg_driver);
269 module_init(msg_init);
271 static void msg_cleanup(void)
273 if (test_and_clear_bit(0, &msg_registered))
274 usb_composite_unregister(&msg_driver);
276 module_exit(msg_cleanup);