xref: /openbmc/linux/drivers/usb/serial/metro-usb.c (revision 12eb4683)
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 #define DRIVER_DESC "Metrologic Instruments Inc. - USB-POS driver"
24 
25 /* Product information. */
26 #define FOCUS_VENDOR_ID			0x0C2E
27 #define FOCUS_PRODUCT_ID_BI		0x0720
28 #define FOCUS_PRODUCT_ID_UNI		0x0700
29 
30 #define METROUSB_SET_REQUEST_TYPE	0x40
31 #define METROUSB_SET_MODEM_CTRL_REQUEST	10
32 #define METROUSB_SET_BREAK_REQUEST	0x40
33 #define METROUSB_MCR_NONE		0x08	/* Deactivate DTR and RTS. */
34 #define METROUSB_MCR_RTS		0x0a	/* Activate RTS. */
35 #define METROUSB_MCR_DTR		0x09	/* Activate DTR. */
36 #define WDR_TIMEOUT			5000	/* default urb timeout. */
37 
38 /* Private data structure. */
39 struct metrousb_private {
40 	spinlock_t lock;
41 	int throttled;
42 	unsigned long control_state;
43 };
44 
45 /* Device table list. */
46 static struct usb_device_id id_table[] = {
47 	{ USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID_BI) },
48 	{ USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID_UNI) },
49 	{ }, /* Terminating entry. */
50 };
51 MODULE_DEVICE_TABLE(usb, id_table);
52 
53 /* UNI-Directional mode commands for device configure */
54 #define UNI_CMD_OPEN	0x80
55 #define UNI_CMD_CLOSE	0xFF
56 
57 inline int metrousb_is_unidirectional_mode(struct usb_serial_port *port)
58 {
59 	__u16 product_id = le16_to_cpu(
60 		port->serial->dev->descriptor.idProduct);
61 
62 	return product_id == FOCUS_PRODUCT_ID_UNI;
63 }
64 
65 static int metrousb_send_unidirectional_cmd(u8 cmd, struct usb_serial_port *port)
66 {
67 	int ret;
68 	int actual_len;
69 	u8 *buffer_cmd = NULL;
70 
71 	if (!metrousb_is_unidirectional_mode(port))
72 		return 0;
73 
74 	buffer_cmd = kzalloc(sizeof(cmd), GFP_KERNEL);
75 	if (!buffer_cmd)
76 		return -ENOMEM;
77 
78 	*buffer_cmd = cmd;
79 
80 	ret = usb_interrupt_msg(port->serial->dev,
81 		usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
82 		buffer_cmd, sizeof(cmd),
83 		&actual_len, USB_CTRL_SET_TIMEOUT);
84 
85 	kfree(buffer_cmd);
86 
87 	if (ret < 0)
88 		return ret;
89 	else if (actual_len != sizeof(cmd))
90 		return -EIO;
91 	return 0;
92 }
93 
94 static void metrousb_read_int_callback(struct urb *urb)
95 {
96 	struct usb_serial_port *port = urb->context;
97 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
98 	unsigned char *data = urb->transfer_buffer;
99 	int throttled = 0;
100 	int result = 0;
101 	unsigned long flags = 0;
102 
103 	dev_dbg(&port->dev, "%s\n", __func__);
104 
105 	switch (urb->status) {
106 	case 0:
107 		/* Success status, read from the port. */
108 		break;
109 	case -ECONNRESET:
110 	case -ENOENT:
111 	case -ESHUTDOWN:
112 		/* urb has been terminated. */
113 		dev_dbg(&port->dev,
114 			"%s - urb shutting down, error code=%d\n",
115 			__func__, urb->status);
116 		return;
117 	default:
118 		dev_dbg(&port->dev,
119 			"%s - non-zero urb received, error code=%d\n",
120 			__func__, urb->status);
121 		goto exit;
122 	}
123 
124 
125 	/* Set the data read from the usb port into the serial port buffer. */
126 	if (urb->actual_length) {
127 		/* Loop through the data copying each byte to the tty layer. */
128 		tty_insert_flip_string(&port->port, data, urb->actual_length);
129 
130 		/* Force the data to the tty layer. */
131 		tty_flip_buffer_push(&port->port);
132 	}
133 
134 	/* Set any port variables. */
135 	spin_lock_irqsave(&metro_priv->lock, flags);
136 	throttled = metro_priv->throttled;
137 	spin_unlock_irqrestore(&metro_priv->lock, flags);
138 
139 	/* Continue trying to read if set. */
140 	if (!throttled) {
141 		usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
142 				 usb_rcvintpipe(port->serial->dev, port->interrupt_in_endpointAddress),
143 				 port->interrupt_in_urb->transfer_buffer,
144 				 port->interrupt_in_urb->transfer_buffer_length,
145 				 metrousb_read_int_callback, port, 1);
146 
147 		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
148 
149 		if (result)
150 			dev_err(&port->dev,
151 				"%s - failed submitting interrupt in urb, error code=%d\n",
152 				__func__, result);
153 	}
154 	return;
155 
156 exit:
157 	/* Try to resubmit the urb. */
158 	result = usb_submit_urb(urb, GFP_ATOMIC);
159 	if (result)
160 		dev_err(&port->dev,
161 			"%s - failed submitting interrupt in urb, error code=%d\n",
162 			__func__, result);
163 }
164 
165 static void metrousb_write_int_callback(struct urb *urb)
166 {
167 	struct usb_serial_port *port = urb->context;
168 
169 	dev_warn(&port->dev, "%s not implemented yet.\n",
170 		__func__);
171 }
172 
173 static void metrousb_cleanup(struct usb_serial_port *port)
174 {
175 	dev_dbg(&port->dev, "%s\n", __func__);
176 
177 	usb_unlink_urb(port->interrupt_in_urb);
178 	usb_kill_urb(port->interrupt_in_urb);
179 
180 	metrousb_send_unidirectional_cmd(UNI_CMD_CLOSE, port);
181 }
182 
183 static int metrousb_open(struct tty_struct *tty, struct usb_serial_port *port)
184 {
185 	struct usb_serial *serial = port->serial;
186 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
187 	unsigned long flags = 0;
188 	int result = 0;
189 
190 	dev_dbg(&port->dev, "%s\n", __func__);
191 
192 	/* Make sure the urb is initialized. */
193 	if (!port->interrupt_in_urb) {
194 		dev_err(&port->dev, "%s - interrupt urb not initialized\n",
195 			__func__);
196 		return -ENODEV;
197 	}
198 
199 	/* Set the private data information for the port. */
200 	spin_lock_irqsave(&metro_priv->lock, flags);
201 	metro_priv->control_state = 0;
202 	metro_priv->throttled = 0;
203 	spin_unlock_irqrestore(&metro_priv->lock, flags);
204 
205 	/* Clear the urb pipe. */
206 	usb_clear_halt(serial->dev, port->interrupt_in_urb->pipe);
207 
208 	/* Start reading from the device */
209 	usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
210 			  usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
211 			   port->interrupt_in_urb->transfer_buffer,
212 			   port->interrupt_in_urb->transfer_buffer_length,
213 			   metrousb_read_int_callback, port, 1);
214 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
215 
216 	if (result) {
217 		dev_err(&port->dev,
218 			"%s - failed submitting interrupt in urb, error code=%d\n",
219 			__func__, result);
220 		goto exit;
221 	}
222 
223 	/* Send activate cmd to device */
224 	result = metrousb_send_unidirectional_cmd(UNI_CMD_OPEN, port);
225 	if (result) {
226 		dev_err(&port->dev,
227 			"%s - failed to configure device, error code=%d\n",
228 			__func__, result);
229 		goto exit;
230 	}
231 
232 	dev_dbg(&port->dev, "%s - port open\n", __func__);
233 exit:
234 	return result;
235 }
236 
237 static int metrousb_set_modem_ctrl(struct usb_serial *serial, unsigned int control_state)
238 {
239 	int retval = 0;
240 	unsigned char mcr = METROUSB_MCR_NONE;
241 
242 	dev_dbg(&serial->dev->dev, "%s - control state = %d\n",
243 		__func__, control_state);
244 
245 	/* Set the modem control value. */
246 	if (control_state & TIOCM_DTR)
247 		mcr |= METROUSB_MCR_DTR;
248 	if (control_state & TIOCM_RTS)
249 		mcr |= METROUSB_MCR_RTS;
250 
251 	/* Send the command to the usb port. */
252 	retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
253 				METROUSB_SET_REQUEST_TYPE, METROUSB_SET_MODEM_CTRL_REQUEST,
254 				control_state, 0, NULL, 0, WDR_TIMEOUT);
255 	if (retval < 0)
256 		dev_err(&serial->dev->dev,
257 			"%s - set modem ctrl=0x%x failed, error code=%d\n",
258 			__func__, mcr, retval);
259 
260 	return retval;
261 }
262 
263 static int metrousb_port_probe(struct usb_serial_port *port)
264 {
265 	struct metrousb_private *metro_priv;
266 
267 	metro_priv = kzalloc(sizeof(*metro_priv), GFP_KERNEL);
268 	if (!metro_priv)
269 		return -ENOMEM;
270 
271 	spin_lock_init(&metro_priv->lock);
272 
273 	usb_set_serial_port_data(port, metro_priv);
274 
275 	return 0;
276 }
277 
278 static int metrousb_port_remove(struct usb_serial_port *port)
279 {
280 	struct metrousb_private *metro_priv;
281 
282 	metro_priv = usb_get_serial_port_data(port);
283 	kfree(metro_priv);
284 
285 	return 0;
286 }
287 
288 static void metrousb_throttle(struct tty_struct *tty)
289 {
290 	struct usb_serial_port *port = tty->driver_data;
291 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
292 	unsigned long flags = 0;
293 
294 	dev_dbg(tty->dev, "%s\n", __func__);
295 
296 	/* Set the private information for the port to stop reading data. */
297 	spin_lock_irqsave(&metro_priv->lock, flags);
298 	metro_priv->throttled = 1;
299 	spin_unlock_irqrestore(&metro_priv->lock, flags);
300 }
301 
302 static int metrousb_tiocmget(struct tty_struct *tty)
303 {
304 	unsigned long control_state = 0;
305 	struct usb_serial_port *port = tty->driver_data;
306 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
307 	unsigned long flags = 0;
308 
309 	dev_dbg(tty->dev, "%s\n", __func__);
310 
311 	spin_lock_irqsave(&metro_priv->lock, flags);
312 	control_state = metro_priv->control_state;
313 	spin_unlock_irqrestore(&metro_priv->lock, flags);
314 
315 	return control_state;
316 }
317 
318 static int metrousb_tiocmset(struct tty_struct *tty,
319 			     unsigned int set, unsigned int clear)
320 {
321 	struct usb_serial_port *port = tty->driver_data;
322 	struct usb_serial *serial = port->serial;
323 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
324 	unsigned long flags = 0;
325 	unsigned long control_state = 0;
326 
327 	dev_dbg(tty->dev, "%s - set=%d, clear=%d\n", __func__, set, clear);
328 
329 	spin_lock_irqsave(&metro_priv->lock, flags);
330 	control_state = metro_priv->control_state;
331 
332 	/* Set the RTS and DTR values. */
333 	if (set & TIOCM_RTS)
334 		control_state |= TIOCM_RTS;
335 	if (set & TIOCM_DTR)
336 		control_state |= TIOCM_DTR;
337 	if (clear & TIOCM_RTS)
338 		control_state &= ~TIOCM_RTS;
339 	if (clear & TIOCM_DTR)
340 		control_state &= ~TIOCM_DTR;
341 
342 	metro_priv->control_state = control_state;
343 	spin_unlock_irqrestore(&metro_priv->lock, flags);
344 	return metrousb_set_modem_ctrl(serial, control_state);
345 }
346 
347 static void metrousb_unthrottle(struct tty_struct *tty)
348 {
349 	struct usb_serial_port *port = tty->driver_data;
350 	struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
351 	unsigned long flags = 0;
352 	int result = 0;
353 
354 	dev_dbg(tty->dev, "%s\n", __func__);
355 
356 	/* Set the private information for the port to resume reading data. */
357 	spin_lock_irqsave(&metro_priv->lock, flags);
358 	metro_priv->throttled = 0;
359 	spin_unlock_irqrestore(&metro_priv->lock, flags);
360 
361 	/* Submit the urb to read from the port. */
362 	port->interrupt_in_urb->dev = port->serial->dev;
363 	result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
364 	if (result)
365 		dev_err(tty->dev,
366 			"failed submitting interrupt in urb error code=%d\n",
367 			result);
368 }
369 
370 static struct usb_serial_driver metrousb_device = {
371 	.driver = {
372 		.owner =	THIS_MODULE,
373 		.name =		"metro-usb",
374 	},
375 	.description		= "Metrologic USB to Serial",
376 	.id_table		= id_table,
377 	.num_ports		= 1,
378 	.open			= metrousb_open,
379 	.close			= metrousb_cleanup,
380 	.read_int_callback	= metrousb_read_int_callback,
381 	.write_int_callback	= metrousb_write_int_callback,
382 	.port_probe		= metrousb_port_probe,
383 	.port_remove		= metrousb_port_remove,
384 	.throttle		= metrousb_throttle,
385 	.unthrottle		= metrousb_unthrottle,
386 	.tiocmget		= metrousb_tiocmget,
387 	.tiocmset		= metrousb_tiocmset,
388 };
389 
390 static struct usb_serial_driver * const serial_drivers[] = {
391 	&metrousb_device,
392 	NULL,
393 };
394 
395 module_usb_serial_driver(serial_drivers, id_table);
396 
397 MODULE_LICENSE("GPL");
398 MODULE_AUTHOR("Philip Nicastro");
399 MODULE_AUTHOR("Aleksey Babahin <tamerlan311@gmail.com>");
400 MODULE_DESCRIPTION(DRIVER_DESC);
401