xref: /linux/drivers/usb/gadget/legacy/printer.c (revision 0d3b051adbb72ed81956447d0d1e54d5943ee6f5)
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 
54 #define QLEN	qlen
55 
56 static struct usb_function_instance *fi_printer;
57 static struct usb_function *f_printer;
58 
59 /*-------------------------------------------------------------------------*/
60 
61 /*
62  * DESCRIPTORS ... most are static, but strings and (full) configuration
63  * descriptors are built on demand.
64  */
65 
66 static struct usb_device_descriptor device_desc = {
67 	.bLength =		sizeof device_desc,
68 	.bDescriptorType =	USB_DT_DEVICE,
69 	/* .bcdUSB = DYNAMIC */
70 	.bDeviceClass =		USB_CLASS_PER_INTERFACE,
71 	.bDeviceSubClass =	0,
72 	.bDeviceProtocol =	0,
73 	.idVendor =		cpu_to_le16(PRINTER_VENDOR_NUM),
74 	.idProduct =		cpu_to_le16(PRINTER_PRODUCT_NUM),
75 	.bNumConfigurations =	1
76 };
77 
78 static const struct usb_descriptor_header *otg_desc[2];
79 
80 /*-------------------------------------------------------------------------*/
81 
82 /* descriptors that are built on-demand */
83 
84 static char				product_desc [40] = DRIVER_DESC;
85 static char				serial_num [40] = "1";
86 static char				*pnp_string =
87 	"MFG:linux;MDL:g_printer;CLS:PRINTER;SN:1;";
88 
89 /* static strings, in UTF-8 */
90 static struct usb_string		strings [] = {
91 	[USB_GADGET_MANUFACTURER_IDX].s = "",
92 	[USB_GADGET_PRODUCT_IDX].s = product_desc,
93 	[USB_GADGET_SERIAL_IDX].s =	serial_num,
94 	{  }		/* end of list */
95 };
96 
97 static struct usb_gadget_strings	stringtab_dev = {
98 	.language	= 0x0409,	/* en-us */
99 	.strings	= strings,
100 };
101 
102 static struct usb_gadget_strings *dev_strings[] = {
103 	&stringtab_dev,
104 	NULL,
105 };
106 
107 static struct usb_configuration printer_cfg_driver = {
108 	.label			= "printer",
109 	.bConfigurationValue	= 1,
110 	.bmAttributes		= USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
111 };
112 
113 static int printer_do_config(struct usb_configuration *c)
114 {
115 	struct usb_gadget	*gadget = c->cdev->gadget;
116 	int			status = 0;
117 
118 	usb_ep_autoconfig_reset(gadget);
119 
120 	usb_gadget_set_selfpowered(gadget);
121 
122 	if (gadget_is_otg(gadget)) {
123 		printer_cfg_driver.descriptors = otg_desc;
124 		printer_cfg_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
125 	}
126 
127 	f_printer = usb_get_function(fi_printer);
128 	if (IS_ERR(f_printer))
129 		return PTR_ERR(f_printer);
130 
131 	status = usb_add_function(c, f_printer);
132 	if (status < 0)
133 		usb_put_function(f_printer);
134 
135 	return status;
136 }
137 
138 static int printer_bind(struct usb_composite_dev *cdev)
139 {
140 	struct f_printer_opts *opts;
141 	int ret;
142 
143 	fi_printer = usb_get_function_instance("printer");
144 	if (IS_ERR(fi_printer))
145 		return PTR_ERR(fi_printer);
146 
147 	opts = container_of(fi_printer, struct f_printer_opts, func_inst);
148 	opts->minor = 0;
149 	opts->q_len = QLEN;
150 	if (iPNPstring) {
151 		opts->pnp_string = kstrdup(iPNPstring, GFP_KERNEL);
152 		if (!opts->pnp_string) {
153 			ret = -ENOMEM;
154 			goto fail_put_func_inst;
155 		}
156 		opts->pnp_string_allocated = true;
157 		/*
158 		 * we don't free this memory in case of error
159 		 * as printer cleanup func will do this for us
160 		 */
161 	} else {
162 		opts->pnp_string = pnp_string;
163 	}
164 
165 	ret = usb_string_ids_tab(cdev, strings);
166 	if (ret < 0)
167 		goto fail_put_func_inst;
168 
169 	device_desc.iManufacturer = strings[USB_GADGET_MANUFACTURER_IDX].id;
170 	device_desc.iProduct = strings[USB_GADGET_PRODUCT_IDX].id;
171 	device_desc.iSerialNumber = strings[USB_GADGET_SERIAL_IDX].id;
172 
173 	if (gadget_is_otg(cdev->gadget) && !otg_desc[0]) {
174 		struct usb_descriptor_header *usb_desc;
175 
176 		usb_desc = usb_otg_descriptor_alloc(cdev->gadget);
177 		if (!usb_desc) {
178 			ret = -ENOMEM;
179 			goto fail_put_func_inst;
180 		}
181 		usb_otg_descriptor_init(cdev->gadget, usb_desc);
182 		otg_desc[0] = usb_desc;
183 		otg_desc[1] = NULL;
184 	}
185 
186 	ret = usb_add_config(cdev, &printer_cfg_driver, printer_do_config);
187 	if (ret)
188 		goto fail_free_otg_desc;
189 
190 	usb_composite_overwrite_options(cdev, &coverwrite);
191 	return ret;
192 
193 fail_free_otg_desc:
194 	kfree(otg_desc[0]);
195 	otg_desc[0] = NULL;
196 fail_put_func_inst:
197 	usb_put_function_instance(fi_printer);
198 	return ret;
199 }
200 
201 static int printer_unbind(struct usb_composite_dev *cdev)
202 {
203 	usb_put_function(f_printer);
204 	usb_put_function_instance(fi_printer);
205 
206 	kfree(otg_desc[0]);
207 	otg_desc[0] = NULL;
208 
209 	return 0;
210 }
211 
212 static struct usb_composite_driver printer_driver = {
213 	.name           = shortname,
214 	.dev            = &device_desc,
215 	.strings        = dev_strings,
216 	.max_speed      = USB_SPEED_SUPER,
217 	.bind		= printer_bind,
218 	.unbind		= printer_unbind,
219 };
220 
221 module_usb_composite_driver(printer_driver);
222 
223 MODULE_DESCRIPTION(DRIVER_DESC);
224 MODULE_AUTHOR("Craig Nadler");
225 MODULE_LICENSE("GPL");
226