xref: /linux/drivers/usb/serial/metro-usb.c (revision c0c914eca7f251c70facc37dfebeaf176601918d)
1 /*
2   Some of this code is credited to Linux USB open source files that are
3   distributed with Linux.
4 
5   Copyright:	2007 Metrologic Instruments. All rights reserved.
6   Copyright:	2011 Azimut Ltd. <http://azimutrzn.ru/>
7 */
8 
9 #include <linux/kernel.h>
10 #include <linux/tty.h>
11 #include <linux/module.h>
12 #include <linux/usb.h>
13 #include <linux/errno.h>
14 #include <linux/slab.h>
15 #include <linux/tty_driver.h>
16 #include <linux/tty_flip.h>
17 #include <linux/moduleparam.h>
18 #include <linux/spinlock.h>
19 #include <linux/uaccess.h>
20 #include <linux/usb/serial.h>
21 
22 #define DRIVER_DESC "Metrologic Instruments Inc. - USB-POS driver"
23 
24 /* Product information. */
25 #define FOCUS_VENDOR_ID			0x0C2E
26 #define FOCUS_PRODUCT_ID_BI		0x0720
27 #define FOCUS_PRODUCT_ID_UNI		0x0700
28 
29 #define METROUSB_SET_REQUEST_TYPE	0x40
30 #define METROUSB_SET_MODEM_CTRL_REQUEST	10
31 #define METROUSB_SET_BREAK_REQUEST	0x40
32 #define METROUSB_MCR_NONE		0x08	/* Deactivate DTR and RTS. */
33 #define METROUSB_MCR_RTS		0x0a	/* Activate RTS. */
34 #define METROUSB_MCR_DTR		0x09	/* Activate DTR. */
35 #define WDR_TIMEOUT			5000	/* default urb timeout. */
36 
37 /* Private data structure. */
38 struct metrousb_private {
39 	spinlock_t lock;
40 	int throttled;
41 	unsigned long control_state;
42 };
43 
44 /* Device table list. */
45 static const struct usb_device_id id_table[] = {
46 	{ USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID_BI) },
47 	{ USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID_UNI) },
48 	{ }, /* Terminating entry. */
49 };
50 MODULE_DEVICE_TABLE(usb, id_table);
51 
52 /* UNI-Directional mode commands for device configure */
53 #define UNI_CMD_OPEN	0x80
54 #define UNI_CMD_CLOSE	0xFF
55 
56 static inline int metrousb_is_unidirectional_mode(struct usb_serial_port *port)
57 {
58 	__u16 product_id = le16_to_cpu(
59 		port->serial->dev->descriptor.idProduct);
60 
61 	return product_id == FOCUS_PRODUCT_ID_UNI;
62 }
63 
64 static int metrousb_send_unidirectional_cmd(u8 cmd, struct usb_serial_port *port)
65 {
66 	int ret;
67 	int actual_len;
68 	u8 *buffer_cmd = NULL;
69 
70 	if (!metrousb_is_unidirectional_mode(port))
71 		return 0;
72 
73 	buffer_cmd = kzalloc(sizeof(cmd), GFP_KERNEL);
74 	if (!buffer_cmd)
75 		return -ENOMEM;
76 
77 	*buffer_cmd = cmd;
78 
79 	ret = usb_interrupt_msg(port->serial->dev,
80 		usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
81 		buffer_cmd, sizeof(cmd),
82 		&actual_len, USB_CTRL_SET_TIMEOUT);
83 
84 	kfree(buffer_cmd);
85 
86 	if (ret < 0)
87 		return ret;
88 	else if (actual_len != sizeof(cmd))
89 		return -EIO;
90 	return 0;
91 }
92 
93 static void metrousb_read_int_callback(struct urb *urb)
94 {
95 	struct usb_serial_port *port = urb->context;
96 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
97 	unsigned char *data = urb->transfer_buffer;
98 	int throttled = 0;
99 	int result = 0;
100 	unsigned long flags = 0;
101 
102 	dev_dbg(&port->dev, "%s\n", __func__);
103 
104 	switch (urb->status) {
105 	case 0:
106 		/* Success status, read from the port. */
107 		break;
108 	case -ECONNRESET:
109 	case -ENOENT:
110 	case -ESHUTDOWN:
111 		/* urb has been terminated. */
112 		dev_dbg(&port->dev,
113 			"%s - urb shutting down, error code=%d\n",
114 			__func__, urb->status);
115 		return;
116 	default:
117 		dev_dbg(&port->dev,
118 			"%s - non-zero urb received, error code=%d\n",
119 			__func__, urb->status);
120 		goto exit;
121 	}
122 
123 
124 	/* Set the data read from the usb port into the serial port buffer. */
125 	if (urb->actual_length) {
126 		/* Loop through the data copying each byte to the tty layer. */
127 		tty_insert_flip_string(&port->port, data, urb->actual_length);
128 
129 		/* Force the data to the tty layer. */
130 		tty_flip_buffer_push(&port->port);
131 	}
132 
133 	/* Set any port variables. */
134 	spin_lock_irqsave(&metro_priv->lock, flags);
135 	throttled = metro_priv->throttled;
136 	spin_unlock_irqrestore(&metro_priv->lock, flags);
137 
138 	/* Continue trying to read if set. */
139 	if (!throttled) {
140 		usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
141 				 usb_rcvintpipe(port->serial->dev, port->interrupt_in_endpointAddress),
142 				 port->interrupt_in_urb->transfer_buffer,
143 				 port->interrupt_in_urb->transfer_buffer_length,
144 				 metrousb_read_int_callback, port, 1);
145 
146 		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
147 
148 		if (result)
149 			dev_err(&port->dev,
150 				"%s - failed submitting interrupt in urb, error code=%d\n",
151 				__func__, result);
152 	}
153 	return;
154 
155 exit:
156 	/* Try to resubmit the urb. */
157 	result = usb_submit_urb(urb, GFP_ATOMIC);
158 	if (result)
159 		dev_err(&port->dev,
160 			"%s - failed submitting interrupt in urb, error code=%d\n",
161 			__func__, result);
162 }
163 
164 static void metrousb_write_int_callback(struct urb *urb)
165 {
166 	struct usb_serial_port *port = urb->context;
167 
168 	dev_warn(&port->dev, "%s not implemented yet.\n",
169 		__func__);
170 }
171 
172 static void metrousb_cleanup(struct usb_serial_port *port)
173 {
174 	dev_dbg(&port->dev, "%s\n", __func__);
175 
176 	usb_unlink_urb(port->interrupt_in_urb);
177 	usb_kill_urb(port->interrupt_in_urb);
178 
179 	metrousb_send_unidirectional_cmd(UNI_CMD_CLOSE, port);
180 }
181 
182 static int metrousb_open(struct tty_struct *tty, struct usb_serial_port *port)
183 {
184 	struct usb_serial *serial = port->serial;
185 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
186 	unsigned long flags = 0;
187 	int result = 0;
188 
189 	dev_dbg(&port->dev, "%s\n", __func__);
190 
191 	/* Make sure the urb is initialized. */
192 	if (!port->interrupt_in_urb) {
193 		dev_err(&port->dev, "%s - interrupt urb not initialized\n",
194 			__func__);
195 		return -ENODEV;
196 	}
197 
198 	/* Set the private data information for the port. */
199 	spin_lock_irqsave(&metro_priv->lock, flags);
200 	metro_priv->control_state = 0;
201 	metro_priv->throttled = 0;
202 	spin_unlock_irqrestore(&metro_priv->lock, flags);
203 
204 	/* Clear the urb pipe. */
205 	usb_clear_halt(serial->dev, port->interrupt_in_urb->pipe);
206 
207 	/* Start reading from the device */
208 	usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
209 			  usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
210 			   port->interrupt_in_urb->transfer_buffer,
211 			   port->interrupt_in_urb->transfer_buffer_length,
212 			   metrousb_read_int_callback, port, 1);
213 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
214 
215 	if (result) {
216 		dev_err(&port->dev,
217 			"%s - failed submitting interrupt in urb, error code=%d\n",
218 			__func__, result);
219 		goto exit;
220 	}
221 
222 	/* Send activate cmd to device */
223 	result = metrousb_send_unidirectional_cmd(UNI_CMD_OPEN, port);
224 	if (result) {
225 		dev_err(&port->dev,
226 			"%s - failed to configure device, error code=%d\n",
227 			__func__, result);
228 		goto exit;
229 	}
230 
231 	dev_dbg(&port->dev, "%s - port open\n", __func__);
232 exit:
233 	return result;
234 }
235 
236 static int metrousb_set_modem_ctrl(struct usb_serial *serial, unsigned int control_state)
237 {
238 	int retval = 0;
239 	unsigned char mcr = METROUSB_MCR_NONE;
240 
241 	dev_dbg(&serial->dev->dev, "%s - control state = %d\n",
242 		__func__, control_state);
243 
244 	/* Set the modem control value. */
245 	if (control_state & TIOCM_DTR)
246 		mcr |= METROUSB_MCR_DTR;
247 	if (control_state & TIOCM_RTS)
248 		mcr |= METROUSB_MCR_RTS;
249 
250 	/* Send the command to the usb port. */
251 	retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
252 				METROUSB_SET_REQUEST_TYPE, METROUSB_SET_MODEM_CTRL_REQUEST,
253 				control_state, 0, NULL, 0, WDR_TIMEOUT);
254 	if (retval < 0)
255 		dev_err(&serial->dev->dev,
256 			"%s - set modem ctrl=0x%x failed, error code=%d\n",
257 			__func__, mcr, retval);
258 
259 	return retval;
260 }
261 
262 static int metrousb_port_probe(struct usb_serial_port *port)
263 {
264 	struct metrousb_private *metro_priv;
265 
266 	metro_priv = kzalloc(sizeof(*metro_priv), GFP_KERNEL);
267 	if (!metro_priv)
268 		return -ENOMEM;
269 
270 	spin_lock_init(&metro_priv->lock);
271 
272 	usb_set_serial_port_data(port, metro_priv);
273 
274 	return 0;
275 }
276 
277 static int metrousb_port_remove(struct usb_serial_port *port)
278 {
279 	struct metrousb_private *metro_priv;
280 
281 	metro_priv = usb_get_serial_port_data(port);
282 	kfree(metro_priv);
283 
284 	return 0;
285 }
286 
287 static void metrousb_throttle(struct tty_struct *tty)
288 {
289 	struct usb_serial_port *port = tty->driver_data;
290 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
291 	unsigned long flags = 0;
292 
293 	dev_dbg(tty->dev, "%s\n", __func__);
294 
295 	/* Set the private information for the port to stop reading data. */
296 	spin_lock_irqsave(&metro_priv->lock, flags);
297 	metro_priv->throttled = 1;
298 	spin_unlock_irqrestore(&metro_priv->lock, flags);
299 }
300 
301 static int metrousb_tiocmget(struct tty_struct *tty)
302 {
303 	unsigned long control_state = 0;
304 	struct usb_serial_port *port = tty->driver_data;
305 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
306 	unsigned long flags = 0;
307 
308 	dev_dbg(tty->dev, "%s\n", __func__);
309 
310 	spin_lock_irqsave(&metro_priv->lock, flags);
311 	control_state = metro_priv->control_state;
312 	spin_unlock_irqrestore(&metro_priv->lock, flags);
313 
314 	return control_state;
315 }
316 
317 static int metrousb_tiocmset(struct tty_struct *tty,
318 			     unsigned int set, unsigned int clear)
319 {
320 	struct usb_serial_port *port = tty->driver_data;
321 	struct usb_serial *serial = port->serial;
322 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
323 	unsigned long flags = 0;
324 	unsigned long control_state = 0;
325 
326 	dev_dbg(tty->dev, "%s - set=%d, clear=%d\n", __func__, set, clear);
327 
328 	spin_lock_irqsave(&metro_priv->lock, flags);
329 	control_state = metro_priv->control_state;
330 
331 	/* Set the RTS and DTR values. */
332 	if (set & TIOCM_RTS)
333 		control_state |= TIOCM_RTS;
334 	if (set & TIOCM_DTR)
335 		control_state |= TIOCM_DTR;
336 	if (clear & TIOCM_RTS)
337 		control_state &= ~TIOCM_RTS;
338 	if (clear & TIOCM_DTR)
339 		control_state &= ~TIOCM_DTR;
340 
341 	metro_priv->control_state = control_state;
342 	spin_unlock_irqrestore(&metro_priv->lock, flags);
343 	return metrousb_set_modem_ctrl(serial, control_state);
344 }
345 
346 static void metrousb_unthrottle(struct tty_struct *tty)
347 {
348 	struct usb_serial_port *port = tty->driver_data;
349 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
350 	unsigned long flags = 0;
351 	int result = 0;
352 
353 	dev_dbg(tty->dev, "%s\n", __func__);
354 
355 	/* Set the private information for the port to resume reading data. */
356 	spin_lock_irqsave(&metro_priv->lock, flags);
357 	metro_priv->throttled = 0;
358 	spin_unlock_irqrestore(&metro_priv->lock, flags);
359 
360 	/* Submit the urb to read from the port. */
361 	port->interrupt_in_urb->dev = port->serial->dev;
362 	result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
363 	if (result)
364 		dev_err(tty->dev,
365 			"failed submitting interrupt in urb error code=%d\n",
366 			result);
367 }
368 
369 static struct usb_serial_driver metrousb_device = {
370 	.driver = {
371 		.owner =	THIS_MODULE,
372 		.name =		"metro-usb",
373 	},
374 	.description		= "Metrologic USB to Serial",
375 	.id_table		= id_table,
376 	.num_ports		= 1,
377 	.open			= metrousb_open,
378 	.close			= metrousb_cleanup,
379 	.read_int_callback	= metrousb_read_int_callback,
380 	.write_int_callback	= metrousb_write_int_callback,
381 	.port_probe		= metrousb_port_probe,
382 	.port_remove		= metrousb_port_remove,
383 	.throttle		= metrousb_throttle,
384 	.unthrottle		= metrousb_unthrottle,
385 	.tiocmget		= metrousb_tiocmget,
386 	.tiocmset		= metrousb_tiocmset,
387 };
388 
389 static struct usb_serial_driver * const serial_drivers[] = {
390 	&metrousb_device,
391 	NULL,
392 };
393 
394 module_usb_serial_driver(serial_drivers, id_table);
395 
396 MODULE_LICENSE("GPL");
397 MODULE_AUTHOR("Philip Nicastro");
398 MODULE_AUTHOR("Aleksey Babahin <tamerlan311@gmail.com>");
399 MODULE_DESCRIPTION(DRIVER_DESC);
400