xref: /openbmc/linux/drivers/usb/serial/ipw.c (revision 6ca98bc2)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * IPWireless 3G UMTS TDD Modem driver (USB connected)
4  *
5  *   Copyright (C) 2004 Roelf Diedericks <roelfd@inet.co.za>
6  *   Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
7  *
8  * All information about the device was acquired using SnoopyPro
9  * on MSFT's O/S, and examing the MSFT drivers' debug output
10  * (insanely left _on_ in the enduser version)
11  *
12  * It was written out of frustration with the IPWireless USB modem
13  * supplied by Axity3G/Sentech South Africa not supporting
14  * Linux whatsoever.
15  *
16  * Nobody provided any proprietary information that was not already
17  * available for this device.
18  *
19  * The modem adheres to the "3GPP TS  27.007 AT command set for 3G
20  * User Equipment (UE)" standard, available from
21  * http://www.3gpp.org/ftp/Specs/html-info/27007.htm
22  *
23  * The code was only tested the IPWireless handheld modem distributed
24  * in South Africa by Sentech.
25  *
26  * It may work for Woosh Inc in .nz too, as it appears they use the
27  * same kit.
28  *
29  * There is still some work to be done in terms of handling
30  * DCD, DTR, RTS, CTS which are currently faked.
31  * It's good enough for PPP at this point. It's based off all kinds of
32  * code found in usb/serial and usb/class
33  */
34 
35 #include <linux/kernel.h>
36 #include <linux/errno.h>
37 #include <linux/slab.h>
38 #include <linux/tty.h>
39 #include <linux/tty_flip.h>
40 #include <linux/module.h>
41 #include <linux/spinlock.h>
42 #include <linux/usb.h>
43 #include <linux/usb/serial.h>
44 #include <linux/uaccess.h>
45 #include "usb-wwan.h"
46 
47 #define DRIVER_AUTHOR	"Roelf Diedericks"
48 #define DRIVER_DESC	"IPWireless tty driver"
49 
50 #define IPW_TTY_MAJOR	240	/* real device node major id, experimental range */
51 #define IPW_TTY_MINORS	256	/* we support 256 devices, dunno why, it'd be insane :) */
52 
53 #define USB_IPW_MAGIC	0x6d02	/* magic number for ipw struct */
54 
55 
56 /* Message sizes */
57 #define EVENT_BUFFER_SIZE	0xFF
58 #define CHAR2INT16(c1, c0)	(((u32)((c1) & 0xff) << 8) + (u32)((c0) & 0xff))
59 
60 /* vendor/product pairs that are known work with this driver*/
61 #define IPW_VID		0x0bc3
62 #define IPW_PID		0x0001
63 
64 
65 /* Vendor commands: */
66 
67 /* baud rates */
68 enum {
69 	ipw_sio_b256000 = 0x000e,
70 	ipw_sio_b128000 = 0x001d,
71 	ipw_sio_b115200 = 0x0020,
72 	ipw_sio_b57600  = 0x0040,
73 	ipw_sio_b56000  = 0x0042,
74 	ipw_sio_b38400  = 0x0060,
75 	ipw_sio_b19200  = 0x00c0,
76 	ipw_sio_b14400  = 0x0100,
77 	ipw_sio_b9600   = 0x0180,
78 	ipw_sio_b4800   = 0x0300,
79 	ipw_sio_b2400   = 0x0600,
80 	ipw_sio_b1200   = 0x0c00,
81 	ipw_sio_b600    = 0x1800
82 };
83 
84 /* data bits */
85 #define ipw_dtb_7		0x700
86 #define ipw_dtb_8		0x810	/* ok so the define is misleading, I know, but forces 8,n,1 */
87 					/* I mean, is there a point to any other setting these days? :) */
88 
89 /* usb control request types : */
90 #define IPW_SIO_RXCTL		0x00	/* control bulk rx channel transmissions, value=1/0 (on/off) */
91 #define IPW_SIO_SET_BAUD	0x01	/* set baud, value=requested ipw_sio_bxxxx */
92 #define IPW_SIO_SET_LINE	0x03	/* set databits, parity. value=ipw_dtb_x */
93 #define IPW_SIO_SET_PIN		0x03	/* set/clear dtr/rts value=ipw_pin_xxx */
94 #define IPW_SIO_POLL		0x08	/* get serial port status byte, call with value=0 */
95 #define IPW_SIO_INIT		0x11	/* initializes ? value=0 (appears as first thing todo on open) */
96 #define IPW_SIO_PURGE		0x12	/* purge all transmissions?, call with value=numchar_to_purge */
97 #define IPW_SIO_HANDFLOW	0x13	/* set xon/xoff limits value=0, and a buffer of 0x10 bytes */
98 #define IPW_SIO_SETCHARS	0x13	/* set the flowcontrol special chars, value=0, buf=6 bytes, */
99 					/* last 2 bytes contain flowcontrol chars e.g. 00 00 00 00 11 13 */
100 
101 /* values used for request IPW_SIO_SET_PIN */
102 #define IPW_PIN_SETDTR		0x101
103 #define IPW_PIN_SETRTS		0x202
104 #define IPW_PIN_CLRDTR		0x100
105 #define IPW_PIN_CLRRTS		0x200 /* unconfirmed */
106 
107 /* values used for request IPW_SIO_RXCTL */
108 #define IPW_RXBULK_ON		1
109 #define IPW_RXBULK_OFF		0
110 
111 /* various 16 byte hardcoded transferbuffers used by flow control */
112 #define IPW_BYTES_FLOWINIT	{ 0x01, 0, 0, 0, 0x40, 0, 0, 0, \
113 					0, 0, 0, 0, 0, 0, 0, 0 }
114 
115 /* Interpretation of modem status lines */
116 /* These need sorting out by individually connecting pins and checking
117  * results. FIXME!
118  * When data is being sent we see 0x30 in the lower byte; this must
119  * contain DSR and CTS ...
120  */
121 #define IPW_DSR			((1<<4) | (1<<5))
122 #define IPW_CTS			((1<<5) | (1<<4))
123 
124 #define IPW_WANTS_TO_SEND	0x30
125 
126 static const struct usb_device_id id_table[] = {
127 	{ USB_DEVICE(IPW_VID, IPW_PID) },
128 	{ },
129 };
130 MODULE_DEVICE_TABLE(usb, id_table);
131 
ipw_open(struct tty_struct * tty,struct usb_serial_port * port)132 static int ipw_open(struct tty_struct *tty, struct usb_serial_port *port)
133 {
134 	struct usb_device *udev = port->serial->dev;
135 	struct device *dev = &port->dev;
136 	u8 buf_flow_static[16] = IPW_BYTES_FLOWINIT;
137 	u8 *buf_flow_init;
138 	int result;
139 
140 	buf_flow_init = kmemdup(buf_flow_static, 16, GFP_KERNEL);
141 	if (!buf_flow_init)
142 		return -ENOMEM;
143 
144 	/* --1: Tell the modem to initialize (we think) From sniffs this is
145 	 *	always the first thing that gets sent to the modem during
146 	 *	opening of the device */
147 	dev_dbg(dev, "%s: Sending SIO_INIT (we guess)\n", __func__);
148 	result = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
149 			 IPW_SIO_INIT,
150 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
151 			 0,
152 			 0, /* index */
153 			 NULL,
154 			 0,
155 			 100000);
156 	if (result < 0)
157 		dev_err(dev, "Init of modem failed (error = %d)\n", result);
158 
159 	/* reset the bulk pipes */
160 	usb_clear_halt(udev, usb_rcvbulkpipe(udev, port->bulk_in_endpointAddress));
161 	usb_clear_halt(udev, usb_sndbulkpipe(udev, port->bulk_out_endpointAddress));
162 
163 	/*--2: Start reading from the device */
164 	dev_dbg(dev, "%s: setting up bulk read callback\n", __func__);
165 	usb_wwan_open(tty, port);
166 
167 	/*--3: Tell the modem to open the floodgates on the rx bulk channel */
168 	dev_dbg(dev, "%s:asking modem for RxRead (RXBULK_ON)\n", __func__);
169 	result = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
170 			 IPW_SIO_RXCTL,
171 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
172 			 IPW_RXBULK_ON,
173 			 0, /* index */
174 			 NULL,
175 			 0,
176 			 100000);
177 	if (result < 0)
178 		dev_err(dev, "Enabling bulk RxRead failed (error = %d)\n", result);
179 
180 	/*--4: setup the initial flowcontrol */
181 	dev_dbg(dev, "%s:setting init flowcontrol (%s)\n", __func__, buf_flow_init);
182 	result = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
183 			 IPW_SIO_HANDFLOW,
184 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
185 			 0,
186 			 0,
187 			 buf_flow_init,
188 			 0x10,
189 			 200000);
190 	if (result < 0)
191 		dev_err(dev, "initial flowcontrol failed (error = %d)\n", result);
192 
193 	kfree(buf_flow_init);
194 	return 0;
195 }
196 
ipw_attach(struct usb_serial * serial)197 static int ipw_attach(struct usb_serial *serial)
198 {
199 	struct usb_wwan_intf_private *data;
200 
201 	data = kzalloc(sizeof(struct usb_wwan_intf_private), GFP_KERNEL);
202 	if (!data)
203 		return -ENOMEM;
204 
205 	spin_lock_init(&data->susp_lock);
206 	usb_set_serial_data(serial, data);
207 	return 0;
208 }
209 
ipw_release(struct usb_serial * serial)210 static void ipw_release(struct usb_serial *serial)
211 {
212 	struct usb_wwan_intf_private *data = usb_get_serial_data(serial);
213 
214 	usb_set_serial_data(serial, NULL);
215 	kfree(data);
216 }
217 
ipw_dtr_rts(struct usb_serial_port * port,int on)218 static void ipw_dtr_rts(struct usb_serial_port *port, int on)
219 {
220 	struct usb_device *udev = port->serial->dev;
221 	struct device *dev = &port->dev;
222 	int result;
223 
224 	dev_dbg(dev, "%s: on = %d\n", __func__, on);
225 
226 	result = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
227 			 IPW_SIO_SET_PIN,
228 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
229 			 on ? IPW_PIN_SETDTR : IPW_PIN_CLRDTR,
230 			 0,
231 			 NULL,
232 			 0,
233 			 200000);
234 	if (result < 0)
235 		dev_err(dev, "setting dtr failed (error = %d)\n", result);
236 
237 	result = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
238 			 IPW_SIO_SET_PIN, USB_TYPE_VENDOR |
239 					USB_RECIP_INTERFACE | USB_DIR_OUT,
240 			 on ? IPW_PIN_SETRTS : IPW_PIN_CLRRTS,
241 			 0,
242 			 NULL,
243 			 0,
244 			 200000);
245 	if (result < 0)
246 		dev_err(dev, "setting rts failed (error = %d)\n", result);
247 }
248 
ipw_close(struct usb_serial_port * port)249 static void ipw_close(struct usb_serial_port *port)
250 {
251 	struct usb_device *udev = port->serial->dev;
252 	struct device *dev = &port->dev;
253 	int result;
254 
255 	/*--3: purge */
256 	dev_dbg(dev, "%s:sending purge\n", __func__);
257 	result = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
258 			 IPW_SIO_PURGE, USB_TYPE_VENDOR |
259 			 		USB_RECIP_INTERFACE | USB_DIR_OUT,
260 			 0x03,
261 			 0,
262 			 NULL,
263 			 0,
264 			 200000);
265 	if (result < 0)
266 		dev_err(dev, "purge failed (error = %d)\n", result);
267 
268 
269 	/* send RXBULK_off (tell modem to stop transmitting bulk data on
270 	   rx chan) */
271 	result = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
272 			 IPW_SIO_RXCTL,
273 			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
274 			 IPW_RXBULK_OFF,
275 			 0, /* index */
276 			 NULL,
277 			 0,
278 			 100000);
279 
280 	if (result < 0)
281 		dev_err(dev, "Disabling bulk RxRead failed (error = %d)\n", result);
282 
283 	usb_wwan_close(port);
284 }
285 
286 static struct usb_serial_driver ipw_device = {
287 	.driver = {
288 		.owner =	THIS_MODULE,
289 		.name =		"ipw",
290 	},
291 	.description =		"IPWireless converter",
292 	.id_table =		id_table,
293 	.num_ports =		1,
294 	.open =			ipw_open,
295 	.close =		ipw_close,
296 	.attach =		ipw_attach,
297 	.release =		ipw_release,
298 	.port_probe =		usb_wwan_port_probe,
299 	.port_remove =		usb_wwan_port_remove,
300 	.dtr_rts =		ipw_dtr_rts,
301 	.write =		usb_wwan_write,
302 };
303 
304 static struct usb_serial_driver * const serial_drivers[] = {
305 	&ipw_device, NULL
306 };
307 
308 module_usb_serial_driver(serial_drivers, id_table);
309 
310 /* Module information */
311 MODULE_AUTHOR(DRIVER_AUTHOR);
312 MODULE_DESCRIPTION(DRIVER_DESC);
313 MODULE_LICENSE("GPL");
314