xref: /openbmc/linux/drivers/usb/serial/metro-usb.c (revision 05bcf503)
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/init.h>
11 #include <linux/tty.h>
12 #include <linux/module.h>
13 #include <linux/usb.h>
14 #include <linux/errno.h>
15 #include <linux/slab.h>
16 #include <linux/tty_driver.h>
17 #include <linux/tty_flip.h>
18 #include <linux/moduleparam.h>
19 #include <linux/spinlock.h>
20 #include <linux/uaccess.h>
21 #include <linux/usb/serial.h>
22 
23 /* Version Information */
24 #define DRIVER_VERSION "v1.2.0.0"
25 #define DRIVER_DESC "Metrologic Instruments Inc. - USB-POS driver"
26 
27 /* Product information. */
28 #define FOCUS_VENDOR_ID			0x0C2E
29 #define FOCUS_PRODUCT_ID_BI		0x0720
30 #define FOCUS_PRODUCT_ID_UNI		0x0700
31 
32 #define METROUSB_SET_REQUEST_TYPE	0x40
33 #define METROUSB_SET_MODEM_CTRL_REQUEST	10
34 #define METROUSB_SET_BREAK_REQUEST	0x40
35 #define METROUSB_MCR_NONE		0x08	/* Deactivate DTR and RTS. */
36 #define METROUSB_MCR_RTS		0x0a	/* Activate RTS. */
37 #define METROUSB_MCR_DTR		0x09	/* Activate DTR. */
38 #define WDR_TIMEOUT			5000	/* default urb timeout. */
39 
40 /* Private data structure. */
41 struct metrousb_private {
42 	spinlock_t lock;
43 	int throttled;
44 	unsigned long control_state;
45 };
46 
47 /* Device table list. */
48 static struct usb_device_id id_table[] = {
49 	{ USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID_BI) },
50 	{ USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID_UNI) },
51 	{ }, /* Terminating entry. */
52 };
53 MODULE_DEVICE_TABLE(usb, id_table);
54 
55 /* UNI-Directional mode commands for device configure */
56 #define UNI_CMD_OPEN	0x80
57 #define UNI_CMD_CLOSE	0xFF
58 
59 inline int metrousb_is_unidirectional_mode(struct usb_serial_port *port)
60 {
61 	__u16 product_id = le16_to_cpu(
62 		port->serial->dev->descriptor.idProduct);
63 
64 	return product_id == FOCUS_PRODUCT_ID_UNI;
65 }
66 
67 static int metrousb_send_unidirectional_cmd(u8 cmd, struct usb_serial_port *port)
68 {
69 	int ret;
70 	int actual_len;
71 	u8 *buffer_cmd = NULL;
72 
73 	if (!metrousb_is_unidirectional_mode(port))
74 		return 0;
75 
76 	buffer_cmd = kzalloc(sizeof(cmd), GFP_KERNEL);
77 	if (!buffer_cmd)
78 		return -ENOMEM;
79 
80 	*buffer_cmd = cmd;
81 
82 	ret = usb_interrupt_msg(port->serial->dev,
83 		usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
84 		buffer_cmd, sizeof(cmd),
85 		&actual_len, USB_CTRL_SET_TIMEOUT);
86 
87 	kfree(buffer_cmd);
88 
89 	if (ret < 0)
90 		return ret;
91 	else if (actual_len != sizeof(cmd))
92 		return -EIO;
93 	return 0;
94 }
95 
96 static void metrousb_read_int_callback(struct urb *urb)
97 {
98 	struct usb_serial_port *port = urb->context;
99 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
100 	struct tty_struct *tty;
101 	unsigned char *data = urb->transfer_buffer;
102 	int throttled = 0;
103 	int result = 0;
104 	unsigned long flags = 0;
105 
106 	dev_dbg(&port->dev, "%s\n", __func__);
107 
108 	switch (urb->status) {
109 	case 0:
110 		/* Success status, read from the port. */
111 		break;
112 	case -ECONNRESET:
113 	case -ENOENT:
114 	case -ESHUTDOWN:
115 		/* urb has been terminated. */
116 		dev_dbg(&port->dev,
117 			"%s - urb shutting down, error code=%d\n",
118 			__func__, urb->status);
119 		return;
120 	default:
121 		dev_dbg(&port->dev,
122 			"%s - non-zero urb received, error code=%d\n",
123 			__func__, urb->status);
124 		goto exit;
125 	}
126 
127 
128 	/* Set the data read from the usb port into the serial port buffer. */
129 	tty = tty_port_tty_get(&port->port);
130 	if (tty && urb->actual_length) {
131 		/* Loop through the data copying each byte to the tty layer. */
132 		tty_insert_flip_string(tty, data, urb->actual_length);
133 
134 		/* Force the data to the tty layer. */
135 		tty_flip_buffer_push(tty);
136 	}
137 	tty_kref_put(tty);
138 
139 	/* Set any port variables. */
140 	spin_lock_irqsave(&metro_priv->lock, flags);
141 	throttled = metro_priv->throttled;
142 	spin_unlock_irqrestore(&metro_priv->lock, flags);
143 
144 	/* Continue trying to read if set. */
145 	if (!throttled) {
146 		usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
147 				 usb_rcvintpipe(port->serial->dev, port->interrupt_in_endpointAddress),
148 				 port->interrupt_in_urb->transfer_buffer,
149 				 port->interrupt_in_urb->transfer_buffer_length,
150 				 metrousb_read_int_callback, port, 1);
151 
152 		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
153 
154 		if (result)
155 			dev_err(&port->dev,
156 				"%s - failed submitting interrupt in urb, error code=%d\n",
157 				__func__, result);
158 	}
159 	return;
160 
161 exit:
162 	/* Try to resubmit the urb. */
163 	result = usb_submit_urb(urb, GFP_ATOMIC);
164 	if (result)
165 		dev_err(&port->dev,
166 			"%s - failed submitting interrupt in urb, error code=%d\n",
167 			__func__, result);
168 }
169 
170 static void metrousb_write_int_callback(struct urb *urb)
171 {
172 	struct usb_serial_port *port = urb->context;
173 
174 	dev_warn(&port->dev, "%s not implemented yet.\n",
175 		__func__);
176 }
177 
178 static void metrousb_cleanup(struct usb_serial_port *port)
179 {
180 	dev_dbg(&port->dev, "%s\n", __func__);
181 
182 	usb_unlink_urb(port->interrupt_in_urb);
183 	usb_kill_urb(port->interrupt_in_urb);
184 
185 	mutex_lock(&port->serial->disc_mutex);
186 	if (!port->serial->disconnected)
187 		metrousb_send_unidirectional_cmd(UNI_CMD_CLOSE, port);
188 	mutex_unlock(&port->serial->disc_mutex);
189 }
190 
191 static int metrousb_open(struct tty_struct *tty, struct usb_serial_port *port)
192 {
193 	struct usb_serial *serial = port->serial;
194 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
195 	unsigned long flags = 0;
196 	int result = 0;
197 
198 	dev_dbg(&port->dev, "%s\n", __func__);
199 
200 	/* Make sure the urb is initialized. */
201 	if (!port->interrupt_in_urb) {
202 		dev_err(&port->dev, "%s - interrupt urb not initialized\n",
203 			__func__);
204 		return -ENODEV;
205 	}
206 
207 	/* Set the private data information for the port. */
208 	spin_lock_irqsave(&metro_priv->lock, flags);
209 	metro_priv->control_state = 0;
210 	metro_priv->throttled = 0;
211 	spin_unlock_irqrestore(&metro_priv->lock, flags);
212 
213 	/* Clear the urb pipe. */
214 	usb_clear_halt(serial->dev, port->interrupt_in_urb->pipe);
215 
216 	/* Start reading from the device */
217 	usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
218 			  usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
219 			   port->interrupt_in_urb->transfer_buffer,
220 			   port->interrupt_in_urb->transfer_buffer_length,
221 			   metrousb_read_int_callback, port, 1);
222 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
223 
224 	if (result) {
225 		dev_err(&port->dev,
226 			"%s - failed submitting interrupt in urb, error code=%d\n",
227 			__func__, result);
228 		goto exit;
229 	}
230 
231 	/* Send activate cmd to device */
232 	result = metrousb_send_unidirectional_cmd(UNI_CMD_OPEN, port);
233 	if (result) {
234 		dev_err(&port->dev,
235 			"%s - failed to configure device for port number=%d, error code=%d\n",
236 			__func__, port->number, result);
237 		goto exit;
238 	}
239 
240 	dev_dbg(&port->dev, "%s - port open\n", __func__);
241 exit:
242 	return result;
243 }
244 
245 static int metrousb_set_modem_ctrl(struct usb_serial *serial, unsigned int control_state)
246 {
247 	int retval = 0;
248 	unsigned char mcr = METROUSB_MCR_NONE;
249 
250 	dev_dbg(&serial->dev->dev, "%s - control state = %d\n",
251 		__func__, control_state);
252 
253 	/* Set the modem control value. */
254 	if (control_state & TIOCM_DTR)
255 		mcr |= METROUSB_MCR_DTR;
256 	if (control_state & TIOCM_RTS)
257 		mcr |= METROUSB_MCR_RTS;
258 
259 	/* Send the command to the usb port. */
260 	retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
261 				METROUSB_SET_REQUEST_TYPE, METROUSB_SET_MODEM_CTRL_REQUEST,
262 				control_state, 0, NULL, 0, WDR_TIMEOUT);
263 	if (retval < 0)
264 		dev_err(&serial->dev->dev,
265 			"%s - set modem ctrl=0x%x failed, error code=%d\n",
266 			__func__, mcr, retval);
267 
268 	return retval;
269 }
270 
271 static int metrousb_port_probe(struct usb_serial_port *port)
272 {
273 	struct metrousb_private *metro_priv;
274 
275 	metro_priv = kzalloc(sizeof(*metro_priv), GFP_KERNEL);
276 	if (!metro_priv)
277 		return -ENOMEM;
278 
279 	spin_lock_init(&metro_priv->lock);
280 
281 	usb_set_serial_port_data(port, metro_priv);
282 
283 	return 0;
284 }
285 
286 static int metrousb_port_remove(struct usb_serial_port *port)
287 {
288 	struct metrousb_private *metro_priv;
289 
290 	metro_priv = usb_get_serial_port_data(port);
291 	kfree(metro_priv);
292 
293 	return 0;
294 }
295 
296 static void metrousb_throttle(struct tty_struct *tty)
297 {
298 	struct usb_serial_port *port = tty->driver_data;
299 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
300 	unsigned long flags = 0;
301 
302 	dev_dbg(tty->dev, "%s\n", __func__);
303 
304 	/* Set the private information for the port to stop reading data. */
305 	spin_lock_irqsave(&metro_priv->lock, flags);
306 	metro_priv->throttled = 1;
307 	spin_unlock_irqrestore(&metro_priv->lock, flags);
308 }
309 
310 static int metrousb_tiocmget(struct tty_struct *tty)
311 {
312 	unsigned long control_state = 0;
313 	struct usb_serial_port *port = tty->driver_data;
314 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
315 	unsigned long flags = 0;
316 
317 	dev_dbg(tty->dev, "%s\n", __func__);
318 
319 	spin_lock_irqsave(&metro_priv->lock, flags);
320 	control_state = metro_priv->control_state;
321 	spin_unlock_irqrestore(&metro_priv->lock, flags);
322 
323 	return control_state;
324 }
325 
326 static int metrousb_tiocmset(struct tty_struct *tty,
327 			     unsigned int set, unsigned int clear)
328 {
329 	struct usb_serial_port *port = tty->driver_data;
330 	struct usb_serial *serial = port->serial;
331 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
332 	unsigned long flags = 0;
333 	unsigned long control_state = 0;
334 
335 	dev_dbg(tty->dev, "%s - set=%d, clear=%d\n", __func__, set, clear);
336 
337 	spin_lock_irqsave(&metro_priv->lock, flags);
338 	control_state = metro_priv->control_state;
339 
340 	/* Set the RTS and DTR values. */
341 	if (set & TIOCM_RTS)
342 		control_state |= TIOCM_RTS;
343 	if (set & TIOCM_DTR)
344 		control_state |= TIOCM_DTR;
345 	if (clear & TIOCM_RTS)
346 		control_state &= ~TIOCM_RTS;
347 	if (clear & TIOCM_DTR)
348 		control_state &= ~TIOCM_DTR;
349 
350 	metro_priv->control_state = control_state;
351 	spin_unlock_irqrestore(&metro_priv->lock, flags);
352 	return metrousb_set_modem_ctrl(serial, control_state);
353 }
354 
355 static void metrousb_unthrottle(struct tty_struct *tty)
356 {
357 	struct usb_serial_port *port = tty->driver_data;
358 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
359 	unsigned long flags = 0;
360 	int result = 0;
361 
362 	dev_dbg(tty->dev, "%s\n", __func__);
363 
364 	/* Set the private information for the port to resume reading data. */
365 	spin_lock_irqsave(&metro_priv->lock, flags);
366 	metro_priv->throttled = 0;
367 	spin_unlock_irqrestore(&metro_priv->lock, flags);
368 
369 	/* Submit the urb to read from the port. */
370 	port->interrupt_in_urb->dev = port->serial->dev;
371 	result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
372 	if (result)
373 		dev_err(tty->dev,
374 			"failed submitting interrupt in urb error code=%d\n",
375 			result);
376 }
377 
378 static struct usb_serial_driver metrousb_device = {
379 	.driver = {
380 		.owner =	THIS_MODULE,
381 		.name =		"metro-usb",
382 	},
383 	.description		= "Metrologic USB to Serial",
384 	.id_table		= id_table,
385 	.num_ports		= 1,
386 	.open			= metrousb_open,
387 	.close			= metrousb_cleanup,
388 	.read_int_callback	= metrousb_read_int_callback,
389 	.write_int_callback	= metrousb_write_int_callback,
390 	.port_probe		= metrousb_port_probe,
391 	.port_remove		= metrousb_port_remove,
392 	.throttle		= metrousb_throttle,
393 	.unthrottle		= metrousb_unthrottle,
394 	.tiocmget		= metrousb_tiocmget,
395 	.tiocmset		= metrousb_tiocmset,
396 };
397 
398 static struct usb_serial_driver * const serial_drivers[] = {
399 	&metrousb_device,
400 	NULL,
401 };
402 
403 module_usb_serial_driver(serial_drivers, id_table);
404 
405 MODULE_LICENSE("GPL");
406 MODULE_AUTHOR("Philip Nicastro");
407 MODULE_AUTHOR("Aleksey Babahin <tamerlan311@gmail.com>");
408 MODULE_DESCRIPTION(DRIVER_DESC);
409