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14#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/slab.h>
19#include <linux/tty.h>
20#include <linux/console.h>
21#include <linux/serial.h>
22#include <linux/usb.h>
23#include <linux/usb/serial.h>
24
25struct usbcons_info {
26 int magic;
27 int break_flag;
28 struct usb_serial_port *port;
29};
30
31static struct usbcons_info usbcons_info;
32static struct console usbcons;
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49
50static const struct tty_operations usb_console_fake_tty_ops = {
51};
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57
58static int usb_console_setup(struct console *co, char *options)
59{
60 struct usbcons_info *info = &usbcons_info;
61 int baud = 9600;
62 int bits = 8;
63 int parity = 'n';
64 int doflow = 0;
65 int cflag = CREAD | HUPCL | CLOCAL;
66 char *s;
67 struct usb_serial *serial;
68 struct usb_serial_port *port;
69 int retval;
70 struct tty_struct *tty = NULL;
71 struct ktermios dummy;
72
73 if (options) {
74 baud = simple_strtoul(options, NULL, 10);
75 s = options;
76 while (*s >= '0' && *s <= '9')
77 s++;
78 if (*s)
79 parity = *s++;
80 if (*s)
81 bits = *s++ - '0';
82 if (*s)
83 doflow = (*s++ == 'r');
84 }
85
86
87 if (baud == 0)
88 baud = 9600;
89
90 switch (bits) {
91 case 7:
92 cflag |= CS7;
93 break;
94 default:
95 case 8:
96 cflag |= CS8;
97 break;
98 }
99 switch (parity) {
100 case 'o': case 'O':
101 cflag |= PARODD;
102 break;
103 case 'e': case 'E':
104 cflag |= PARENB;
105 break;
106 }
107 co->cflag = cflag;
108
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110
111
112
113 port = usb_serial_port_get_by_minor(co->index);
114 if (port == NULL) {
115
116 pr_err("No USB device connected to ttyUSB%i\n", co->index);
117 return -ENODEV;
118 }
119 serial = port->serial;
120
121 retval = usb_autopm_get_interface(serial->interface);
122 if (retval)
123 goto error_get_interface;
124
125 tty_port_tty_set(&port->port, NULL);
126
127 info->port = port;
128
129 ++port->port.count;
130 if (!test_bit(ASYNCB_INITIALIZED, &port->port.flags)) {
131 if (serial->type->set_termios) {
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137 tty = kzalloc(sizeof(*tty), GFP_KERNEL);
138 if (!tty) {
139 retval = -ENOMEM;
140 goto reset_open_count;
141 }
142 kref_init(&tty->kref);
143 tty->driver = usb_serial_tty_driver;
144 tty->index = co->index;
145 init_ldsem(&tty->ldisc_sem);
146 INIT_LIST_HEAD(&tty->tty_files);
147 kref_get(&tty->driver->kref);
148 __module_get(tty->driver->owner);
149 tty->ops = &usb_console_fake_tty_ops;
150 if (tty_init_termios(tty)) {
151 retval = -ENOMEM;
152 goto put_tty;
153 }
154 tty_port_tty_set(&port->port, tty);
155 }
156
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159 retval = serial->type->open(NULL, port);
160 if (retval) {
161 dev_err(&port->dev, "could not open USB console port\n");
162 goto fail;
163 }
164
165 if (serial->type->set_termios) {
166 tty->termios.c_cflag = cflag;
167 tty_termios_encode_baud_rate(&tty->termios, baud, baud);
168 memset(&dummy, 0, sizeof(struct ktermios));
169 serial->type->set_termios(tty, port, &dummy);
170
171 tty_port_tty_set(&port->port, NULL);
172 tty_kref_put(tty);
173 }
174 set_bit(ASYNCB_INITIALIZED, &port->port.flags);
175 }
176
177
178 --port->port.count;
179
180
181 port->port.console = 1;
182
183 mutex_unlock(&serial->disc_mutex);
184 return retval;
185
186 fail:
187 tty_port_tty_set(&port->port, NULL);
188 put_tty:
189 tty_kref_put(tty);
190 reset_open_count:
191 port->port.count = 0;
192 usb_autopm_put_interface(serial->interface);
193 error_get_interface:
194 usb_serial_put(serial);
195 mutex_unlock(&serial->disc_mutex);
196 return retval;
197}
198
199static void usb_console_write(struct console *co,
200 const char *buf, unsigned count)
201{
202 static struct usbcons_info *info = &usbcons_info;
203 struct usb_serial_port *port = info->port;
204 struct usb_serial *serial;
205 int retval = -ENODEV;
206
207 if (!port || port->serial->dev->state == USB_STATE_NOTATTACHED)
208 return;
209 serial = port->serial;
210
211 if (count == 0)
212 return;
213
214 dev_dbg(&port->dev, "%s - %d byte(s)\n", __func__, count);
215
216 if (!port->port.console) {
217 dev_dbg(&port->dev, "%s - port not opened\n", __func__);
218 return;
219 }
220
221 while (count) {
222 unsigned int i;
223 unsigned int lf;
224
225 for (i = 0, lf = 0 ; i < count ; i++) {
226 if (*(buf + i) == 10) {
227 lf = 1;
228 i++;
229 break;
230 }
231 }
232
233
234 retval = serial->type->write(NULL, port, buf, i);
235 dev_dbg(&port->dev, "%s - write: %d\n", __func__, retval);
236 if (lf) {
237
238 unsigned char cr = 13;
239 retval = serial->type->write(NULL, port, &cr, 1);
240 dev_dbg(&port->dev, "%s - write cr: %d\n",
241 __func__, retval);
242 }
243 buf += i;
244 count -= i;
245 }
246}
247
248static struct tty_driver *usb_console_device(struct console *co, int *index)
249{
250 struct tty_driver **p = (struct tty_driver **)co->data;
251
252 if (!*p)
253 return NULL;
254
255 *index = co->index;
256 return *p;
257}
258
259static struct console usbcons = {
260 .name = "ttyUSB",
261 .write = usb_console_write,
262 .device = usb_console_device,
263 .setup = usb_console_setup,
264 .flags = CON_PRINTBUFFER,
265 .index = -1,
266 .data = &usb_serial_tty_driver,
267};
268
269void usb_serial_console_disconnect(struct usb_serial *serial)
270{
271 if (serial && serial->port && serial->port[0]
272 && serial->port[0] == usbcons_info.port) {
273 usb_serial_console_exit();
274 usb_serial_put(serial);
275 }
276}
277
278void usb_serial_console_init(int minor)
279{
280 if (minor == 0) {
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294 pr_debug("registering the USB serial console.\n");
295 register_console(&usbcons);
296 }
297}
298
299void usb_serial_console_exit(void)
300{
301 if (usbcons_info.port) {
302 unregister_console(&usbcons);
303 usbcons_info.port->port.console = 0;
304 usbcons_info.port = NULL;
305 }
306}
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