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
18USB_GADGET_COMPOSITE_OPTIONS();
19
20#define DRIVER_DESC		"Printer Gadget"
21#define DRIVER_VERSION		"2015 FEB 17"
22
23static 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
43module_param_named(iSerialNum, coverwrite.serial_number, charp, S_IRUGO);
44MODULE_PARM_DESC(iSerialNum, "1");
45
46static char *iPNPstring;
47module_param(iPNPstring, charp, S_IRUGO);
48MODULE_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. */
51static unsigned qlen = 10;
52module_param(qlen, uint, S_IRUGO|S_IWUSR);
53
54#define QLEN	qlen
55
56static struct usb_function_instance *fi_printer;
57static 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
66static 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
78static const struct usb_descriptor_header *otg_desc[2];
79
80/*-------------------------------------------------------------------------*/
81
82/* descriptors that are built on-demand */
83
84static char				product_desc [40] = DRIVER_DESC;
85static char				serial_num [40] = "1";
86static char				*pnp_string =
87	"MFG:linux;MDL:g_printer;CLS:PRINTER;SN:1;";
88
89/* static strings, in UTF-8 */
90static 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
97static struct usb_gadget_strings	stringtab_dev = {
98	.language	= 0x0409,	/* en-us */
99	.strings	= strings,
100};
101
102static struct usb_gadget_strings *dev_strings[] = {
103	&stringtab_dev,
104	NULL,
105};
106
107static struct usb_configuration printer_cfg_driver = {
108	.label			= "printer",
109	.bConfigurationValue	= 1,
110	.bmAttributes		= USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
111};
112
113static 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
138static 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
193fail_free_otg_desc:
194	kfree(otg_desc[0]);
195	otg_desc[0] = NULL;
196fail_put_func_inst:
197	usb_put_function_instance(fi_printer);
198	return ret;
199}
200
201static 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
212static 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
221module_usb_composite_driver(printer_driver);
222
223MODULE_DESCRIPTION(DRIVER_DESC);
224MODULE_AUTHOR("Craig Nadler");
225MODULE_LICENSE("GPL");
226