1 // SPDX-License-Identifier: GPL-2.0+
3 * serial.c -- USB gadget serial driver
5 * Copyright (C) 2003 Al Borchers (alborchers@steinerpoint.com)
6 * Copyright (C) 2008 by David Brownell
7 * Copyright (C) 2008 by Nokia Corporation
10 #include <linux/kernel.h>
11 #include <linux/device.h>
12 #include <linux/module.h>
13 #include <linux/tty.h>
14 #include <linux/tty_flip.h>
21 #define GS_VERSION_STR "v2.4"
22 #define GS_VERSION_NUM 0x2400
24 #define GS_LONG_NAME "Gadget Serial"
25 #define GS_VERSION_NAME GS_LONG_NAME " " GS_VERSION_STR
27 /*-------------------------------------------------------------------------*/
28 USB_GADGET_COMPOSITE_OPTIONS();
30 /* Thanks to NetChip Technologies for donating this product ID.
32 * DO NOT REUSE THESE IDs with a protocol-incompatible driver!! Ever!!
33 * Instead: allocate your own, using normal USB-IF procedures.
35 #define GS_VENDOR_ID 0x0525 /* NetChip */
36 #define GS_PRODUCT_ID 0xa4a6 /* Linux-USB Serial Gadget */
37 #define GS_CDC_PRODUCT_ID 0xa4a7 /* ... as CDC-ACM */
38 #define GS_CDC_OBEX_PRODUCT_ID 0xa4a9 /* ... as CDC-OBEX */
40 /* string IDs are assigned dynamically */
42 #define STRING_DESCRIPTION_IDX USB_GADGET_FIRST_AVAIL_IDX
44 static struct usb_string strings_dev
[] = {
45 [USB_GADGET_MANUFACTURER_IDX
].s
= "",
46 [USB_GADGET_PRODUCT_IDX
].s
= GS_VERSION_NAME
,
47 [USB_GADGET_SERIAL_IDX
].s
= "",
48 [STRING_DESCRIPTION_IDX
].s
= NULL
/* updated; f(use_acm) */,
52 static struct usb_gadget_strings stringtab_dev
= {
53 .language
= 0x0409, /* en-us */
54 .strings
= strings_dev
,
57 static struct usb_gadget_strings
*dev_strings
[] = {
62 static struct usb_device_descriptor device_desc
= {
63 .bLength
= USB_DT_DEVICE_SIZE
,
64 .bDescriptorType
= USB_DT_DEVICE
,
65 /* .bcdUSB = DYNAMIC */
66 /* .bDeviceClass = f(use_acm) */
69 /* .bMaxPacketSize0 = f(hardware) */
70 .idVendor
= cpu_to_le16(GS_VENDOR_ID
),
71 /* .idProduct = f(use_acm) */
72 .bcdDevice
= cpu_to_le16(GS_VERSION_NUM
),
73 /* .iManufacturer = DYNAMIC */
74 /* .iProduct = DYNAMIC */
75 .bNumConfigurations
= 1,
78 static const struct usb_descriptor_header
*otg_desc
[2];
80 /*-------------------------------------------------------------------------*/
83 MODULE_DESCRIPTION(GS_VERSION_NAME
);
84 MODULE_AUTHOR("Al Borchers");
85 MODULE_AUTHOR("David Brownell");
86 MODULE_LICENSE("GPL");
88 static bool use_acm
= true;
89 module_param(use_acm
, bool, 0);
90 MODULE_PARM_DESC(use_acm
, "Use CDC ACM, default=yes");
92 static bool use_obex
= false;
93 module_param(use_obex
, bool, 0);
94 MODULE_PARM_DESC(use_obex
, "Use CDC OBEX, default=no");
96 static unsigned n_ports
= 1;
97 module_param(n_ports
, uint
, 0);
98 MODULE_PARM_DESC(n_ports
, "number of ports to create, default=1");
100 static bool enable
= true;
102 static int switch_gserial_enable(bool do_enable
);
104 static int enable_set(const char *s
, const struct kernel_param
*kp
)
109 if (!s
) /* called for no-arg enable == default */
112 ret
= strtobool(s
, &do_enable
);
113 if (ret
|| enable
== do_enable
)
116 ret
= switch_gserial_enable(do_enable
);
123 static const struct kernel_param_ops enable_ops
= {
125 .get
= param_get_bool
,
128 module_param_cb(enable
, &enable_ops
, &enable
, 0644);
130 /*-------------------------------------------------------------------------*/
132 static struct usb_configuration serial_config_driver
= {
133 /* .label = f(use_acm) */
134 /* .bConfigurationValue = f(use_acm) */
135 /* .iConfiguration = DYNAMIC */
136 .bmAttributes
= USB_CONFIG_ATT_SELFPOWER
,
139 static struct usb_function_instance
*fi_serial
[MAX_U_SERIAL_PORTS
];
140 static struct usb_function
*f_serial
[MAX_U_SERIAL_PORTS
];
142 static int serial_register_ports(struct usb_composite_dev
*cdev
,
143 struct usb_configuration
*c
, const char *f_name
)
148 ret
= usb_add_config_only(cdev
, c
);
152 for (i
= 0; i
< n_ports
; i
++) {
154 fi_serial
[i
] = usb_get_function_instance(f_name
);
155 if (IS_ERR(fi_serial
[i
])) {
156 ret
= PTR_ERR(fi_serial
[i
]);
160 f_serial
[i
] = usb_get_function(fi_serial
[i
]);
161 if (IS_ERR(f_serial
[i
])) {
162 ret
= PTR_ERR(f_serial
[i
]);
166 ret
= usb_add_function(c
, f_serial
[i
]);
174 usb_put_function(f_serial
[i
]);
176 usb_put_function_instance(fi_serial
[i
]);
181 usb_remove_function(c
, f_serial
[i
]);
182 usb_put_function(f_serial
[i
]);
183 usb_put_function_instance(fi_serial
[i
]);
190 static int gs_bind(struct usb_composite_dev
*cdev
)
194 /* Allocate string descriptor numbers ... note that string
195 * contents can be overridden by the composite_dev glue.
198 status
= usb_string_ids_tab(cdev
, strings_dev
);
201 device_desc
.iManufacturer
= strings_dev
[USB_GADGET_MANUFACTURER_IDX
].id
;
202 device_desc
.iProduct
= strings_dev
[USB_GADGET_PRODUCT_IDX
].id
;
203 status
= strings_dev
[STRING_DESCRIPTION_IDX
].id
;
204 serial_config_driver
.iConfiguration
= status
;
206 if (gadget_is_otg(cdev
->gadget
)) {
208 struct usb_descriptor_header
*usb_desc
;
210 usb_desc
= usb_otg_descriptor_alloc(cdev
->gadget
);
215 usb_otg_descriptor_init(cdev
->gadget
, usb_desc
);
216 otg_desc
[0] = usb_desc
;
219 serial_config_driver
.descriptors
= otg_desc
;
220 serial_config_driver
.bmAttributes
|= USB_CONFIG_ATT_WAKEUP
;
223 /* register our configuration */
225 status
= serial_register_ports(cdev
, &serial_config_driver
,
227 usb_ep_autoconfig_reset(cdev
->gadget
);
229 status
= serial_register_ports(cdev
, &serial_config_driver
,
232 status
= serial_register_ports(cdev
, &serial_config_driver
,
238 usb_composite_overwrite_options(cdev
, &coverwrite
);
239 INFO(cdev
, "%s\n", GS_VERSION_NAME
);
249 static int gs_unbind(struct usb_composite_dev
*cdev
)
253 for (i
= 0; i
< n_ports
; i
++) {
254 usb_put_function(f_serial
[i
]);
255 usb_put_function_instance(fi_serial
[i
]);
264 static struct usb_composite_driver gserial_driver
= {
267 .strings
= dev_strings
,
268 .max_speed
= USB_SPEED_SUPER
,
273 static int switch_gserial_enable(bool do_enable
)
275 if (!serial_config_driver
.label
)
276 /* init() was not called, yet */
280 return usb_composite_probe(&gserial_driver
);
282 usb_composite_unregister(&gserial_driver
);
286 static int __init
init(void)
288 /* We *could* export two configs; that'd be much cleaner...
289 * but neither of these product IDs was defined that way.
292 serial_config_driver
.label
= "CDC ACM config";
293 serial_config_driver
.bConfigurationValue
= 2;
294 device_desc
.bDeviceClass
= USB_CLASS_COMM
;
295 device_desc
.idProduct
=
296 cpu_to_le16(GS_CDC_PRODUCT_ID
);
297 } else if (use_obex
) {
298 serial_config_driver
.label
= "CDC OBEX config";
299 serial_config_driver
.bConfigurationValue
= 3;
300 device_desc
.bDeviceClass
= USB_CLASS_COMM
;
301 device_desc
.idProduct
=
302 cpu_to_le16(GS_CDC_OBEX_PRODUCT_ID
);
304 serial_config_driver
.label
= "Generic Serial config";
305 serial_config_driver
.bConfigurationValue
= 1;
306 device_desc
.bDeviceClass
= USB_CLASS_VENDOR_SPEC
;
307 device_desc
.idProduct
=
308 cpu_to_le16(GS_PRODUCT_ID
);
310 strings_dev
[STRING_DESCRIPTION_IDX
].s
= serial_config_driver
.label
;
315 return usb_composite_probe(&gserial_driver
);
319 static void __exit
cleanup(void)
322 usb_composite_unregister(&gserial_driver
);
324 module_exit(cleanup
);