1 // SPDX-License-Identifier: GPL-2.0
2 /* Target based USB-Gadget
3 *
4 * UAS protocol handling, target callbacks, configfs handling,
5 * BBB (USB Mass Storage Class Bulk-Only (BBB) and Transport protocol handling.
6 *
7 * Author: Sebastian Andrzej Siewior <bigeasy at linutronix dot de>
8 */
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/types.h>
12 #include <linux/string.h>
13 #include <linux/configfs.h>
14 #include <linux/ctype.h>
15 #include <linux/usb/ch9.h>
16 #include <linux/usb/composite.h>
17 #include <linux/usb/gadget.h>
18 #include <linux/usb/storage.h>
19 #include <scsi/scsi_tcq.h>
20 #include <target/target_core_base.h>
21 #include <target/target_core_fabric.h>
22 #include <asm/unaligned.h>
23
24 #include "u_tcm.h"
25
26 USB_GADGET_COMPOSITE_OPTIONS();
27
28 #define UAS_VENDOR_ID 0x0525 /* NetChip */
29 #define UAS_PRODUCT_ID 0xa4a5 /* Linux-USB File-backed Storage Gadget */
30
31 static struct usb_device_descriptor usbg_device_desc = {
32 .bLength = sizeof(usbg_device_desc),
33 .bDescriptorType = USB_DT_DEVICE,
34 /* .bcdUSB = DYNAMIC */
35 .bDeviceClass = USB_CLASS_PER_INTERFACE,
36 .idVendor = cpu_to_le16(UAS_VENDOR_ID),
37 .idProduct = cpu_to_le16(UAS_PRODUCT_ID),
38 .bNumConfigurations = 1,
39 };
40
41 #define USB_G_STR_CONFIG USB_GADGET_FIRST_AVAIL_IDX
42
43 static struct usb_string usbg_us_strings[] = {
44 [USB_GADGET_MANUFACTURER_IDX].s = "Target Manufacturer",
45 [USB_GADGET_PRODUCT_IDX].s = "Target Product",
46 [USB_GADGET_SERIAL_IDX].s = "000000000001",
47 [USB_G_STR_CONFIG].s = "default config",
48 { },
49 };
50
51 static struct usb_gadget_strings usbg_stringtab = {
52 .language = 0x0409,
53 .strings = usbg_us_strings,
54 };
55
56 static struct usb_gadget_strings *usbg_strings[] = {
57 &usbg_stringtab,
58 NULL,
59 };
60
61 static struct usb_function_instance *fi_tcm;
62 static struct usb_function *f_tcm;
63
guas_unbind(struct usb_composite_dev * cdev)64 static int guas_unbind(struct usb_composite_dev *cdev)
65 {
66 if (!IS_ERR_OR_NULL(f_tcm))
67 usb_put_function(f_tcm);
68
69 return 0;
70 }
71
tcm_do_config(struct usb_configuration * c)72 static int tcm_do_config(struct usb_configuration *c)
73 {
74 int status;
75
76 f_tcm = usb_get_function(fi_tcm);
77 if (IS_ERR(f_tcm))
78 return PTR_ERR(f_tcm);
79
80 status = usb_add_function(c, f_tcm);
81 if (status < 0) {
82 usb_put_function(f_tcm);
83 return status;
84 }
85
86 return 0;
87 }
88
89 static struct usb_configuration usbg_config_driver = {
90 .label = "Linux Target",
91 .bConfigurationValue = 1,
92 .bmAttributes = USB_CONFIG_ATT_SELFPOWER,
93 };
94
95 static int usbg_attach(struct usb_function_instance *f);
96 static void usbg_detach(struct usb_function_instance *f);
97
usb_target_bind(struct usb_composite_dev * cdev)98 static int usb_target_bind(struct usb_composite_dev *cdev)
99 {
100 int ret;
101
102 ret = usb_string_ids_tab(cdev, usbg_us_strings);
103 if (ret)
104 return ret;
105
106 usbg_device_desc.iManufacturer =
107 usbg_us_strings[USB_GADGET_MANUFACTURER_IDX].id;
108 usbg_device_desc.iProduct = usbg_us_strings[USB_GADGET_PRODUCT_IDX].id;
109 usbg_device_desc.iSerialNumber =
110 usbg_us_strings[USB_GADGET_SERIAL_IDX].id;
111 usbg_config_driver.iConfiguration =
112 usbg_us_strings[USB_G_STR_CONFIG].id;
113
114 ret = usb_add_config(cdev, &usbg_config_driver, tcm_do_config);
115 if (ret)
116 return ret;
117 usb_composite_overwrite_options(cdev, &coverwrite);
118 return 0;
119 }
120
121 static struct usb_composite_driver usbg_driver = {
122 .name = "g_target",
123 .dev = &usbg_device_desc,
124 .strings = usbg_strings,
125 .max_speed = USB_SPEED_SUPER,
126 .bind = usb_target_bind,
127 .unbind = guas_unbind,
128 };
129
usbg_attach(struct usb_function_instance * f)130 static int usbg_attach(struct usb_function_instance *f)
131 {
132 return usb_composite_probe(&usbg_driver);
133 }
134
usbg_detach(struct usb_function_instance * f)135 static void usbg_detach(struct usb_function_instance *f)
136 {
137 usb_composite_unregister(&usbg_driver);
138 }
139
usb_target_gadget_init(void)140 static int __init usb_target_gadget_init(void)
141 {
142 struct f_tcm_opts *tcm_opts;
143
144 fi_tcm = usb_get_function_instance("tcm");
145 if (IS_ERR(fi_tcm))
146 return PTR_ERR(fi_tcm);
147
148 tcm_opts = container_of(fi_tcm, struct f_tcm_opts, func_inst);
149 mutex_lock(&tcm_opts->dep_lock);
150 tcm_opts->tcm_register_callback = usbg_attach;
151 tcm_opts->tcm_unregister_callback = usbg_detach;
152 tcm_opts->dependent = THIS_MODULE;
153 tcm_opts->can_attach = true;
154 tcm_opts->has_dep = true;
155 mutex_unlock(&tcm_opts->dep_lock);
156
157 fi_tcm->set_inst_name(fi_tcm, "tcm-legacy");
158
159 return 0;
160 }
161 module_init(usb_target_gadget_init);
162
usb_target_gadget_exit(void)163 static void __exit usb_target_gadget_exit(void)
164 {
165 if (!IS_ERR_OR_NULL(fi_tcm))
166 usb_put_function_instance(fi_tcm);
167
168 }
169 module_exit(usb_target_gadget_exit);
170
171 MODULE_AUTHOR("Sebastian Andrzej Siewior <bigeasy@linutronix.de>");
172 MODULE_DESCRIPTION("usb-gadget fabric");
173 MODULE_LICENSE("GPL v2");
174