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 */
68enum {
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
126static const struct usb_device_id id_table[] = {
127	{ USB_DEVICE(IPW_VID, IPW_PID) },
128	{ },
129};
130MODULE_DEVICE_TABLE(usb, id_table);
131
132static 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
197static 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
210static 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
218static 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
249static 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
286static 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
304static struct usb_serial_driver * const serial_drivers[] = {
305	&ipw_device, NULL
306};
307
308module_usb_serial_driver(serial_drivers, id_table);
309
310/* Module information */
311MODULE_AUTHOR(DRIVER_AUTHOR);
312MODULE_DESCRIPTION(DRIVER_DESC);
313MODULE_LICENSE("GPL");
314