1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * printer.c -- Printer gadget driver
4 *
5 * Copyright (C) 2003-2005 David Brownell
6 * Copyright (C) 2006 Craig W. Nadler
7 */
8
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <asm/byteorder.h>
12
13 #include <linux/usb/ch9.h>
14 #include <linux/usb/composite.h>
15 #include <linux/usb/gadget.h>
16 #include <linux/usb/g_printer.h>
17
18 USB_GADGET_COMPOSITE_OPTIONS();
19
20 #define DRIVER_DESC "Printer Gadget"
21 #define DRIVER_VERSION "2015 FEB 17"
22
23 static const char shortname [] = "printer";
24
25 #include "u_printer.h"
26
27 /*-------------------------------------------------------------------------*/
28
29 /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!! Ever!!
30 * Instead: allocate your own, using normal USB-IF procedures.
31 */
32
33 /* Thanks to NetChip Technologies for donating this product ID.
34 */
35 #define PRINTER_VENDOR_NUM 0x0525 /* NetChip */
36 #define PRINTER_PRODUCT_NUM 0xa4a8 /* Linux-USB Printer Gadget */
37
38 /* Some systems will want different product identifiers published in the
39 * device descriptor, either numbers or strings or both. These string
40 * parameters are in UTF-8 (superset of ASCII's 7 bit characters).
41 */
42
43 module_param_named(iSerialNum, coverwrite.serial_number, charp, S_IRUGO);
44 MODULE_PARM_DESC(iSerialNum, "1");
45
46 static char *iPNPstring;
47 module_param(iPNPstring, charp, S_IRUGO);
48 MODULE_PARM_DESC(iPNPstring, "MFG:linux;MDL:g_printer;CLS:PRINTER;SN:1;");
49
50 /* Number of requests to allocate per endpoint, not used for ep0. */
51 static unsigned qlen = 10;
52 module_param(qlen, uint, S_IRUGO|S_IWUSR);
53 MODULE_PARM_DESC(qlen, "The number of 8k buffers to use per endpoint");
54
55 #define QLEN qlen
56
57 static struct usb_function_instance *fi_printer;
58 static struct usb_function *f_printer;
59
60 /*-------------------------------------------------------------------------*/
61
62 /*
63 * DESCRIPTORS ... most are static, but strings and (full) configuration
64 * descriptors are built on demand.
65 */
66
67 static struct usb_device_descriptor device_desc = {
68 .bLength = sizeof device_desc,
69 .bDescriptorType = USB_DT_DEVICE,
70 /* .bcdUSB = DYNAMIC */
71 .bDeviceClass = USB_CLASS_PER_INTERFACE,
72 .bDeviceSubClass = 0,
73 .bDeviceProtocol = 0,
74 .idVendor = cpu_to_le16(PRINTER_VENDOR_NUM),
75 .idProduct = cpu_to_le16(PRINTER_PRODUCT_NUM),
76 .bNumConfigurations = 1
77 };
78
79 static const struct usb_descriptor_header *otg_desc[2];
80
81 /*-------------------------------------------------------------------------*/
82
83 /* descriptors that are built on-demand */
84
85 static char product_desc [40] = DRIVER_DESC;
86 static char serial_num [40] = "1";
87 static char *pnp_string =
88 "MFG:linux;MDL:g_printer;CLS:PRINTER;SN:1;";
89
90 /* static strings, in UTF-8 */
91 static struct usb_string strings [] = {
92 [USB_GADGET_MANUFACTURER_IDX].s = "",
93 [USB_GADGET_PRODUCT_IDX].s = product_desc,
94 [USB_GADGET_SERIAL_IDX].s = serial_num,
95 { } /* end of list */
96 };
97
98 static struct usb_gadget_strings stringtab_dev = {
99 .language = 0x0409, /* en-us */
100 .strings = strings,
101 };
102
103 static struct usb_gadget_strings *dev_strings[] = {
104 &stringtab_dev,
105 NULL,
106 };
107
108 static struct usb_configuration printer_cfg_driver = {
109 .label = "printer",
110 .bConfigurationValue = 1,
111 .bmAttributes = USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
112 };
113
printer_do_config(struct usb_configuration * c)114 static int printer_do_config(struct usb_configuration *c)
115 {
116 struct usb_gadget *gadget = c->cdev->gadget;
117 int status = 0;
118
119 usb_ep_autoconfig_reset(gadget);
120
121 usb_gadget_set_selfpowered(gadget);
122
123 if (gadget_is_otg(gadget)) {
124 printer_cfg_driver.descriptors = otg_desc;
125 printer_cfg_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
126 }
127
128 f_printer = usb_get_function(fi_printer);
129 if (IS_ERR(f_printer))
130 return PTR_ERR(f_printer);
131
132 status = usb_add_function(c, f_printer);
133 if (status < 0)
134 usb_put_function(f_printer);
135
136 return status;
137 }
138
printer_bind(struct usb_composite_dev * cdev)139 static int printer_bind(struct usb_composite_dev *cdev)
140 {
141 struct f_printer_opts *opts;
142 int ret;
143
144 fi_printer = usb_get_function_instance("printer");
145 if (IS_ERR(fi_printer))
146 return PTR_ERR(fi_printer);
147
148 opts = container_of(fi_printer, struct f_printer_opts, func_inst);
149 opts->minor = 0;
150 opts->q_len = QLEN;
151 if (iPNPstring) {
152 opts->pnp_string = kstrdup(iPNPstring, GFP_KERNEL);
153 if (!opts->pnp_string) {
154 ret = -ENOMEM;
155 goto fail_put_func_inst;
156 }
157 opts->pnp_string_allocated = true;
158 /*
159 * we don't free this memory in case of error
160 * as printer cleanup func will do this for us
161 */
162 } else {
163 opts->pnp_string = pnp_string;
164 }
165
166 ret = usb_string_ids_tab(cdev, strings);
167 if (ret < 0)
168 goto fail_put_func_inst;
169
170 device_desc.iManufacturer = strings[USB_GADGET_MANUFACTURER_IDX].id;
171 device_desc.iProduct = strings[USB_GADGET_PRODUCT_IDX].id;
172 device_desc.iSerialNumber = strings[USB_GADGET_SERIAL_IDX].id;
173
174 if (gadget_is_otg(cdev->gadget) && !otg_desc[0]) {
175 struct usb_descriptor_header *usb_desc;
176
177 usb_desc = usb_otg_descriptor_alloc(cdev->gadget);
178 if (!usb_desc) {
179 ret = -ENOMEM;
180 goto fail_put_func_inst;
181 }
182 usb_otg_descriptor_init(cdev->gadget, usb_desc);
183 otg_desc[0] = usb_desc;
184 otg_desc[1] = NULL;
185 }
186
187 ret = usb_add_config(cdev, &printer_cfg_driver, printer_do_config);
188 if (ret)
189 goto fail_free_otg_desc;
190
191 usb_composite_overwrite_options(cdev, &coverwrite);
192 return ret;
193
194 fail_free_otg_desc:
195 kfree(otg_desc[0]);
196 otg_desc[0] = NULL;
197 fail_put_func_inst:
198 usb_put_function_instance(fi_printer);
199 return ret;
200 }
201
printer_unbind(struct usb_composite_dev * cdev)202 static int printer_unbind(struct usb_composite_dev *cdev)
203 {
204 usb_put_function(f_printer);
205 usb_put_function_instance(fi_printer);
206
207 kfree(otg_desc[0]);
208 otg_desc[0] = NULL;
209
210 return 0;
211 }
212
213 static struct usb_composite_driver printer_driver = {
214 .name = shortname,
215 .dev = &device_desc,
216 .strings = dev_strings,
217 .max_speed = USB_SPEED_SUPER,
218 .bind = printer_bind,
219 .unbind = printer_unbind,
220 };
221
222 module_usb_composite_driver(printer_driver);
223
224 MODULE_DESCRIPTION(DRIVER_DESC);
225 MODULE_AUTHOR("Craig Nadler");
226 MODULE_LICENSE("GPL");
227