xref: /linux/drivers/net/hamradio/yam.c (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
1 /*****************************************************************************/
2 
3 /*
4  *    yam.c  -- YAM radio modem driver.
5  *
6  *      Copyright (C) 1998 Frederic Rible F1OAT (frible@teaser.fr)
7  *      Adapted from baycom.c driver written by Thomas Sailer (sailer@ife.ee.ethz.ch)
8  *
9  *      This program is free software; you can redistribute it and/or modify
10  *      it under the terms of the GNU General Public License as published by
11  *      the Free Software Foundation; either version 2 of the License, or
12  *      (at your option) any later version.
13  *
14  *      This program is distributed in the hope that it will be useful,
15  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
16  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  *      GNU General Public License for more details.
18  *
19  *      You should have received a copy of the GNU General Public License
20  *      along with this program; if not, write to the Free Software
21  *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  *
23  *  Please note that the GPL allows you to use the driver, NOT the radio.
24  *  In order to use the radio, you need a license from the communications
25  *  authority of your country.
26  *
27  *
28  *  History:
29  *   0.0 F1OAT 06.06.98  Begin of work with baycom.c source code V 0.3
30  *   0.1 F1OAT 07.06.98  Add timer polling routine for channel arbitration
31  *   0.2 F6FBB 08.06.98  Added delay after FPGA programming
32  *   0.3 F6FBB 29.07.98  Delayed PTT implementation for dupmode=2
33  *   0.4 F6FBB 30.07.98  Added TxTail, Slottime and Persistence
34  *   0.5 F6FBB 01.08.98  Shared IRQs, /proc/net and network statistics
35  *   0.6 F6FBB 25.08.98  Added 1200Bds format
36  *   0.7 F6FBB 12.09.98  Added to the kernel configuration
37  *   0.8 F6FBB 14.10.98  Fixed slottime/persistence timing bug
38  *       OK1ZIA 2.09.01  Fixed "kfree_skb on hard IRQ"
39  *                       using dev_kfree_skb_any(). (important in 2.4 kernel)
40  *
41  */
42 
43 /*****************************************************************************/
44 
45 #include <linux/module.h>
46 #include <linux/types.h>
47 #include <linux/net.h>
48 #include <linux/in.h>
49 #include <linux/if.h>
50 #include <linux/slab.h>
51 #include <linux/errno.h>
52 #include <linux/bitops.h>
53 #include <linux/random.h>
54 #include <asm/io.h>
55 #include <asm/system.h>
56 #include <linux/interrupt.h>
57 #include <linux/ioport.h>
58 #include <linux/firmware.h>
59 #include <linux/platform_device.h>
60 
61 #include <linux/netdevice.h>
62 #include <linux/if_arp.h>
63 #include <linux/etherdevice.h>
64 #include <linux/skbuff.h>
65 #include <net/ax25.h>
66 
67 #include <linux/kernel.h>
68 #include <linux/proc_fs.h>
69 #include <linux/seq_file.h>
70 #include <net/net_namespace.h>
71 
72 #include <asm/uaccess.h>
73 #include <linux/init.h>
74 
75 #include <linux/yam.h>
76 
77 /* --------------------------------------------------------------------- */
78 
79 static const char yam_drvname[] = "yam";
80 static const char yam_drvinfo[] __initdata = KERN_INFO \
81 	"YAM driver version 0.8 by F1OAT/F6FBB\n";
82 
83 /* --------------------------------------------------------------------- */
84 
85 #define FIRMWARE_9600	"yam/9600.bin"
86 #define FIRMWARE_1200	"yam/1200.bin"
87 
88 #define YAM_9600	1
89 #define YAM_1200	2
90 
91 #define NR_PORTS	4
92 #define YAM_MAGIC	0xF10A7654
93 
94 /* Transmitter states */
95 
96 #define TX_OFF		0
97 #define TX_HEAD		1
98 #define TX_DATA		2
99 #define TX_CRC1		3
100 #define TX_CRC2		4
101 #define TX_TAIL		5
102 
103 #define YAM_MAX_FRAME	1024
104 
105 #define DEFAULT_BITRATE	9600			/* bps */
106 #define DEFAULT_HOLDD	10			/* sec */
107 #define DEFAULT_TXD	300			/* ms */
108 #define DEFAULT_TXTAIL	10			/* ms */
109 #define DEFAULT_SLOT	100			/* ms */
110 #define DEFAULT_PERS	64			/* 0->255 */
111 
112 struct yam_port {
113 	int magic;
114 	int bitrate;
115 	int baudrate;
116 	int iobase;
117 	int irq;
118 	int dupmode;
119 
120 	struct net_device *dev;
121 
122 	int nb_rxint;
123 	int nb_mdint;
124 
125 	/* Parameters section */
126 
127 	int txd;				/* tx delay */
128 	int holdd;				/* duplex ptt delay */
129 	int txtail;				/* txtail delay */
130 	int slot;				/* slottime */
131 	int pers;				/* persistence */
132 
133 	/* Tx section */
134 
135 	int tx_state;
136 	int tx_count;
137 	int slotcnt;
138 	unsigned char tx_buf[YAM_MAX_FRAME];
139 	int tx_len;
140 	int tx_crcl, tx_crch;
141 	struct sk_buff_head send_queue;		/* Packets awaiting transmission */
142 
143 	/* Rx section */
144 
145 	int dcd;
146 	unsigned char rx_buf[YAM_MAX_FRAME];
147 	int rx_len;
148 	int rx_crcl, rx_crch;
149 };
150 
151 struct yam_mcs {
152 	unsigned char bits[YAM_FPGA_SIZE];
153 	int bitrate;
154 	struct yam_mcs *next;
155 };
156 
157 static struct net_device *yam_devs[NR_PORTS];
158 
159 static struct yam_mcs *yam_data;
160 
161 static DEFINE_TIMER(yam_timer, NULL, 0, 0);
162 
163 /* --------------------------------------------------------------------- */
164 
165 #define RBR(iobase)	(iobase+0)
166 #define THR(iobase)	(iobase+0)
167 #define IER(iobase)	(iobase+1)
168 #define IIR(iobase)	(iobase+2)
169 #define FCR(iobase)	(iobase+2)
170 #define LCR(iobase)	(iobase+3)
171 #define MCR(iobase)	(iobase+4)
172 #define LSR(iobase)	(iobase+5)
173 #define MSR(iobase)	(iobase+6)
174 #define SCR(iobase)	(iobase+7)
175 #define DLL(iobase)	(iobase+0)
176 #define DLM(iobase)	(iobase+1)
177 
178 #define YAM_EXTENT	8
179 
180 /* Interrupt Identification Register Bit Masks */
181 #define IIR_NOPEND	1
182 #define IIR_MSR		0
183 #define IIR_TX		2
184 #define IIR_RX		4
185 #define IIR_LSR		6
186 #define IIR_TIMEOUT	12			/* Fifo mode only */
187 
188 #define IIR_MASK	0x0F
189 
190 /* Interrupt Enable Register Bit Masks */
191 #define IER_RX		1			/* enable rx interrupt */
192 #define IER_TX		2			/* enable tx interrupt */
193 #define IER_LSR		4			/* enable line status interrupts */
194 #define IER_MSR		8			/* enable modem status interrupts */
195 
196 /* Modem Control Register Bit Masks */
197 #define MCR_DTR		0x01			/* DTR output */
198 #define MCR_RTS		0x02			/* RTS output */
199 #define MCR_OUT1	0x04			/* OUT1 output (not accessible in RS232) */
200 #define MCR_OUT2	0x08			/* Master Interrupt enable (must be set on PCs) */
201 #define MCR_LOOP	0x10			/* Loopback enable */
202 
203 /* Modem Status Register Bit Masks */
204 #define MSR_DCTS	0x01			/* Delta CTS input */
205 #define MSR_DDSR	0x02			/* Delta DSR */
206 #define MSR_DRIN	0x04			/* Delta RI */
207 #define MSR_DDCD	0x08			/* Delta DCD */
208 #define MSR_CTS		0x10			/* CTS input */
209 #define MSR_DSR		0x20			/* DSR input */
210 #define MSR_RING	0x40			/* RI  input */
211 #define MSR_DCD		0x80			/* DCD input */
212 
213 /* line status register bit mask */
214 #define LSR_RXC		0x01
215 #define LSR_OE		0x02
216 #define LSR_PE		0x04
217 #define LSR_FE		0x08
218 #define LSR_BREAK	0x10
219 #define LSR_THRE	0x20
220 #define LSR_TSRE	0x40
221 
222 /* Line Control Register Bit Masks */
223 #define LCR_DLAB	0x80
224 #define LCR_BREAK	0x40
225 #define LCR_PZERO	0x28
226 #define LCR_PEVEN	0x18
227 #define LCR_PODD	0x08
228 #define LCR_STOP1	0x00
229 #define LCR_STOP2	0x04
230 #define LCR_BIT5	0x00
231 #define LCR_BIT6	0x02
232 #define LCR_BIT7	0x01
233 #define LCR_BIT8	0x03
234 
235 /* YAM Modem <-> UART Port mapping */
236 
237 #define TX_RDY		MSR_DCTS		/* transmitter ready to send */
238 #define RX_DCD		MSR_DCD			/* carrier detect */
239 #define RX_FLAG		MSR_RING		/* hdlc flag received */
240 #define FPGA_DONE	MSR_DSR			/* FPGA is configured */
241 #define PTT_ON		(MCR_RTS|MCR_OUT2)	/* activate PTT */
242 #define PTT_OFF		(MCR_DTR|MCR_OUT2)	/* release PTT */
243 
244 #define ENABLE_RXINT	IER_RX			/* enable uart rx interrupt during rx */
245 #define ENABLE_TXINT	IER_MSR			/* enable uart ms interrupt during tx */
246 #define ENABLE_RTXINT	(IER_RX|IER_MSR)	/* full duplex operations */
247 
248 
249 /*************************************************************************
250 * CRC Tables
251 ************************************************************************/
252 
253 static const unsigned char chktabl[256] =
254 {0x00, 0x89, 0x12, 0x9b, 0x24, 0xad, 0x36, 0xbf, 0x48, 0xc1, 0x5a, 0xd3, 0x6c, 0xe5, 0x7e,
255  0xf7, 0x81, 0x08, 0x93, 0x1a, 0xa5, 0x2c, 0xb7, 0x3e, 0xc9, 0x40, 0xdb, 0x52, 0xed, 0x64,
256  0xff, 0x76, 0x02, 0x8b, 0x10, 0x99, 0x26, 0xaf, 0x34, 0xbd, 0x4a, 0xc3, 0x58, 0xd1, 0x6e,
257  0xe7, 0x7c, 0xf5, 0x83, 0x0a, 0x91, 0x18, 0xa7, 0x2e, 0xb5, 0x3c, 0xcb, 0x42, 0xd9, 0x50,
258  0xef, 0x66, 0xfd, 0x74, 0x04, 0x8d, 0x16, 0x9f, 0x20, 0xa9, 0x32, 0xbb, 0x4c, 0xc5, 0x5e,
259  0xd7, 0x68, 0xe1, 0x7a, 0xf3, 0x85, 0x0c, 0x97, 0x1e, 0xa1, 0x28, 0xb3, 0x3a, 0xcd, 0x44,
260  0xdf, 0x56, 0xe9, 0x60, 0xfb, 0x72, 0x06, 0x8f, 0x14, 0x9d, 0x22, 0xab, 0x30, 0xb9, 0x4e,
261  0xc7, 0x5c, 0xd5, 0x6a, 0xe3, 0x78, 0xf1, 0x87, 0x0e, 0x95, 0x1c, 0xa3, 0x2a, 0xb1, 0x38,
262  0xcf, 0x46, 0xdd, 0x54, 0xeb, 0x62, 0xf9, 0x70, 0x08, 0x81, 0x1a, 0x93, 0x2c, 0xa5, 0x3e,
263  0xb7, 0x40, 0xc9, 0x52, 0xdb, 0x64, 0xed, 0x76, 0xff, 0x89, 0x00, 0x9b, 0x12, 0xad, 0x24,
264  0xbf, 0x36, 0xc1, 0x48, 0xd3, 0x5a, 0xe5, 0x6c, 0xf7, 0x7e, 0x0a, 0x83, 0x18, 0x91, 0x2e,
265  0xa7, 0x3c, 0xb5, 0x42, 0xcb, 0x50, 0xd9, 0x66, 0xef, 0x74, 0xfd, 0x8b, 0x02, 0x99, 0x10,
266  0xaf, 0x26, 0xbd, 0x34, 0xc3, 0x4a, 0xd1, 0x58, 0xe7, 0x6e, 0xf5, 0x7c, 0x0c, 0x85, 0x1e,
267  0x97, 0x28, 0xa1, 0x3a, 0xb3, 0x44, 0xcd, 0x56, 0xdf, 0x60, 0xe9, 0x72, 0xfb, 0x8d, 0x04,
268  0x9f, 0x16, 0xa9, 0x20, 0xbb, 0x32, 0xc5, 0x4c, 0xd7, 0x5e, 0xe1, 0x68, 0xf3, 0x7a, 0x0e,
269  0x87, 0x1c, 0x95, 0x2a, 0xa3, 0x38, 0xb1, 0x46, 0xcf, 0x54, 0xdd, 0x62, 0xeb, 0x70, 0xf9,
270  0x8f, 0x06, 0x9d, 0x14, 0xab, 0x22, 0xb9, 0x30, 0xc7, 0x4e, 0xd5, 0x5c, 0xe3, 0x6a, 0xf1,
271  0x78};
272 static const unsigned char chktabh[256] =
273 {0x00, 0x11, 0x23, 0x32, 0x46, 0x57, 0x65, 0x74, 0x8c, 0x9d, 0xaf, 0xbe, 0xca, 0xdb, 0xe9,
274  0xf8, 0x10, 0x01, 0x33, 0x22, 0x56, 0x47, 0x75, 0x64, 0x9c, 0x8d, 0xbf, 0xae, 0xda, 0xcb,
275  0xf9, 0xe8, 0x21, 0x30, 0x02, 0x13, 0x67, 0x76, 0x44, 0x55, 0xad, 0xbc, 0x8e, 0x9f, 0xeb,
276  0xfa, 0xc8, 0xd9, 0x31, 0x20, 0x12, 0x03, 0x77, 0x66, 0x54, 0x45, 0xbd, 0xac, 0x9e, 0x8f,
277  0xfb, 0xea, 0xd8, 0xc9, 0x42, 0x53, 0x61, 0x70, 0x04, 0x15, 0x27, 0x36, 0xce, 0xdf, 0xed,
278  0xfc, 0x88, 0x99, 0xab, 0xba, 0x52, 0x43, 0x71, 0x60, 0x14, 0x05, 0x37, 0x26, 0xde, 0xcf,
279  0xfd, 0xec, 0x98, 0x89, 0xbb, 0xaa, 0x63, 0x72, 0x40, 0x51, 0x25, 0x34, 0x06, 0x17, 0xef,
280  0xfe, 0xcc, 0xdd, 0xa9, 0xb8, 0x8a, 0x9b, 0x73, 0x62, 0x50, 0x41, 0x35, 0x24, 0x16, 0x07,
281  0xff, 0xee, 0xdc, 0xcd, 0xb9, 0xa8, 0x9a, 0x8b, 0x84, 0x95, 0xa7, 0xb6, 0xc2, 0xd3, 0xe1,
282  0xf0, 0x08, 0x19, 0x2b, 0x3a, 0x4e, 0x5f, 0x6d, 0x7c, 0x94, 0x85, 0xb7, 0xa6, 0xd2, 0xc3,
283  0xf1, 0xe0, 0x18, 0x09, 0x3b, 0x2a, 0x5e, 0x4f, 0x7d, 0x6c, 0xa5, 0xb4, 0x86, 0x97, 0xe3,
284  0xf2, 0xc0, 0xd1, 0x29, 0x38, 0x0a, 0x1b, 0x6f, 0x7e, 0x4c, 0x5d, 0xb5, 0xa4, 0x96, 0x87,
285  0xf3, 0xe2, 0xd0, 0xc1, 0x39, 0x28, 0x1a, 0x0b, 0x7f, 0x6e, 0x5c, 0x4d, 0xc6, 0xd7, 0xe5,
286  0xf4, 0x80, 0x91, 0xa3, 0xb2, 0x4a, 0x5b, 0x69, 0x78, 0x0c, 0x1d, 0x2f, 0x3e, 0xd6, 0xc7,
287  0xf5, 0xe4, 0x90, 0x81, 0xb3, 0xa2, 0x5a, 0x4b, 0x79, 0x68, 0x1c, 0x0d, 0x3f, 0x2e, 0xe7,
288  0xf6, 0xc4, 0xd5, 0xa1, 0xb0, 0x82, 0x93, 0x6b, 0x7a, 0x48, 0x59, 0x2d, 0x3c, 0x0e, 0x1f,
289  0xf7, 0xe6, 0xd4, 0xc5, 0xb1, 0xa0, 0x92, 0x83, 0x7b, 0x6a, 0x58, 0x49, 0x3d, 0x2c, 0x1e,
290  0x0f};
291 
292 /*************************************************************************
293 * FPGA functions
294 ************************************************************************/
295 
296 static void delay(int ms)
297 {
298 	unsigned long timeout = jiffies + ((ms * HZ) / 1000);
299 	while (time_before(jiffies, timeout))
300 		cpu_relax();
301 }
302 
303 /*
304  * reset FPGA
305  */
306 
307 static void fpga_reset(int iobase)
308 {
309 	outb(0, IER(iobase));
310 	outb(LCR_DLAB | LCR_BIT5, LCR(iobase));
311 	outb(1, DLL(iobase));
312 	outb(0, DLM(iobase));
313 
314 	outb(LCR_BIT5, LCR(iobase));
315 	inb(LSR(iobase));
316 	inb(MSR(iobase));
317 	/* turn off FPGA supply voltage */
318 	outb(MCR_OUT1 | MCR_OUT2, MCR(iobase));
319 	delay(100);
320 	/* turn on FPGA supply voltage again */
321 	outb(MCR_DTR | MCR_RTS | MCR_OUT1 | MCR_OUT2, MCR(iobase));
322 	delay(100);
323 }
324 
325 /*
326  * send one byte to FPGA
327  */
328 
329 static int fpga_write(int iobase, unsigned char wrd)
330 {
331 	unsigned char bit;
332 	int k;
333 	unsigned long timeout = jiffies + HZ / 10;
334 
335 	for (k = 0; k < 8; k++) {
336 		bit = (wrd & 0x80) ? (MCR_RTS | MCR_DTR) : MCR_DTR;
337 		outb(bit | MCR_OUT1 | MCR_OUT2, MCR(iobase));
338 		wrd <<= 1;
339 		outb(0xfc, THR(iobase));
340 		while ((inb(LSR(iobase)) & LSR_TSRE) == 0)
341 			if (time_after(jiffies, timeout))
342 				return -1;
343 	}
344 
345 	return 0;
346 }
347 
348 /*
349  * predef should be 0 for loading user defined mcs
350  * predef should be YAM_1200 for loading predef 1200 mcs
351  * predef should be YAM_9600 for loading predef 9600 mcs
352  */
353 static unsigned char *add_mcs(unsigned char *bits, int bitrate,
354 			      unsigned int predef)
355 {
356 	const char *fw_name[2] = {FIRMWARE_9600, FIRMWARE_1200};
357 	const struct firmware *fw;
358 	struct platform_device *pdev;
359 	struct yam_mcs *p;
360 	int err;
361 
362 	switch (predef) {
363 	case 0:
364 		fw = NULL;
365 		break;
366 	case YAM_1200:
367 	case YAM_9600:
368 		predef--;
369 		pdev = platform_device_register_simple("yam", 0, NULL, 0);
370 		if (IS_ERR(pdev)) {
371 			printk(KERN_ERR "yam: Failed to register firmware\n");
372 			return NULL;
373 		}
374 		err = request_firmware(&fw, fw_name[predef], &pdev->dev);
375 		platform_device_unregister(pdev);
376 		if (err) {
377 			printk(KERN_ERR "Failed to load firmware \"%s\"\n",
378 			       fw_name[predef]);
379 			return NULL;
380 		}
381 		if (fw->size != YAM_FPGA_SIZE) {
382 			printk(KERN_ERR "Bogus length %zu in firmware \"%s\"\n",
383 			       fw->size, fw_name[predef]);
384 			release_firmware(fw);
385 			return NULL;
386 		}
387 		bits = (unsigned char *)fw->data;
388 		break;
389 	default:
390 		printk(KERN_ERR "yam: Invalid predef number %u\n", predef);
391 		return NULL;
392 	}
393 
394 	/* If it already exists, replace the bit data */
395 	p = yam_data;
396 	while (p) {
397 		if (p->bitrate == bitrate) {
398 			memcpy(p->bits, bits, YAM_FPGA_SIZE);
399 			goto out;
400 		}
401 		p = p->next;
402 	}
403 
404 	/* Allocate a new mcs */
405 	if ((p = kmalloc(sizeof(struct yam_mcs), GFP_KERNEL)) == NULL) {
406 		printk(KERN_WARNING "YAM: no memory to allocate mcs\n");
407 		release_firmware(fw);
408 		return NULL;
409 	}
410 	memcpy(p->bits, bits, YAM_FPGA_SIZE);
411 	p->bitrate = bitrate;
412 	p->next = yam_data;
413 	yam_data = p;
414  out:
415 	release_firmware(fw);
416 	return p->bits;
417 }
418 
419 static unsigned char *get_mcs(int bitrate)
420 {
421 	struct yam_mcs *p;
422 
423 	p = yam_data;
424 	while (p) {
425 		if (p->bitrate == bitrate)
426 			return p->bits;
427 		p = p->next;
428 	}
429 
430 	/* Load predefined mcs data */
431 	switch (bitrate) {
432 	case 1200:
433 		/* setting predef as YAM_1200 for loading predef 1200 mcs */
434 		return add_mcs(NULL, bitrate, YAM_1200);
435 	default:
436 		/* setting predef as YAM_9600 for loading predef 9600 mcs */
437 		return add_mcs(NULL, bitrate, YAM_9600);
438 	}
439 }
440 
441 /*
442  * download bitstream to FPGA
443  * data is contained in bits[] array in yam1200.h resp. yam9600.h
444  */
445 
446 static int fpga_download(int iobase, int bitrate)
447 {
448 	int i, rc;
449 	unsigned char *pbits;
450 
451 	pbits = get_mcs(bitrate);
452 	if (pbits == NULL)
453 		return -1;
454 
455 	fpga_reset(iobase);
456 	for (i = 0; i < YAM_FPGA_SIZE; i++) {
457 		if (fpga_write(iobase, pbits[i])) {
458 			printk(KERN_ERR "yam: error in write cycle\n");
459 			return -1;			/* write... */
460 		}
461 	}
462 
463 	fpga_write(iobase, 0xFF);
464 	rc = inb(MSR(iobase));		/* check DONE signal */
465 
466 	/* Needed for some hardwares */
467 	delay(50);
468 
469 	return (rc & MSR_DSR) ? 0 : -1;
470 }
471 
472 
473 /************************************************************************
474 * Serial port init
475 ************************************************************************/
476 
477 static void yam_set_uart(struct net_device *dev)
478 {
479 	struct yam_port *yp = netdev_priv(dev);
480 	int divisor = 115200 / yp->baudrate;
481 
482 	outb(0, IER(dev->base_addr));
483 	outb(LCR_DLAB | LCR_BIT8, LCR(dev->base_addr));
484 	outb(divisor, DLL(dev->base_addr));
485 	outb(0, DLM(dev->base_addr));
486 	outb(LCR_BIT8, LCR(dev->base_addr));
487 	outb(PTT_OFF, MCR(dev->base_addr));
488 	outb(0x00, FCR(dev->base_addr));
489 
490 	/* Flush pending irq */
491 
492 	inb(RBR(dev->base_addr));
493 	inb(MSR(dev->base_addr));
494 
495 	/* Enable rx irq */
496 
497 	outb(ENABLE_RTXINT, IER(dev->base_addr));
498 }
499 
500 
501 /* --------------------------------------------------------------------- */
502 
503 enum uart {
504 	c_uart_unknown, c_uart_8250,
505 	c_uart_16450, c_uart_16550, c_uart_16550A
506 };
507 
508 static const char *uart_str[] =
509 {"unknown", "8250", "16450", "16550", "16550A"};
510 
511 static enum uart yam_check_uart(unsigned int iobase)
512 {
513 	unsigned char b1, b2, b3;
514 	enum uart u;
515 	enum uart uart_tab[] =
516 	{c_uart_16450, c_uart_unknown, c_uart_16550, c_uart_16550A};
517 
518 	b1 = inb(MCR(iobase));
519 	outb(b1 | 0x10, MCR(iobase));	/* loopback mode */
520 	b2 = inb(MSR(iobase));
521 	outb(0x1a, MCR(iobase));
522 	b3 = inb(MSR(iobase)) & 0xf0;
523 	outb(b1, MCR(iobase));		/* restore old values */
524 	outb(b2, MSR(iobase));
525 	if (b3 != 0x90)
526 		return c_uart_unknown;
527 	inb(RBR(iobase));
528 	inb(RBR(iobase));
529 	outb(0x01, FCR(iobase));	/* enable FIFOs */
530 	u = uart_tab[(inb(IIR(iobase)) >> 6) & 3];
531 	if (u == c_uart_16450) {
532 		outb(0x5a, SCR(iobase));
533 		b1 = inb(SCR(iobase));
534 		outb(0xa5, SCR(iobase));
535 		b2 = inb(SCR(iobase));
536 		if ((b1 != 0x5a) || (b2 != 0xa5))
537 			u = c_uart_8250;
538 	}
539 	return u;
540 }
541 
542 /******************************************************************************
543 * Rx Section
544 ******************************************************************************/
545 static inline void yam_rx_flag(struct net_device *dev, struct yam_port *yp)
546 {
547 	if (yp->dcd && yp->rx_len >= 3 && yp->rx_len < YAM_MAX_FRAME) {
548 		int pkt_len = yp->rx_len - 2 + 1;	/* -CRC + kiss */
549 		struct sk_buff *skb;
550 
551 		if ((yp->rx_crch & yp->rx_crcl) != 0xFF) {
552 			/* Bad crc */
553 		} else {
554 			if (!(skb = dev_alloc_skb(pkt_len))) {
555 				printk(KERN_WARNING "%s: memory squeeze, dropping packet\n", dev->name);
556 				++dev->stats.rx_dropped;
557 			} else {
558 				unsigned char *cp;
559 				cp = skb_put(skb, pkt_len);
560 				*cp++ = 0;		/* KISS kludge */
561 				memcpy(cp, yp->rx_buf, pkt_len - 1);
562 				skb->protocol = ax25_type_trans(skb, dev);
563 				netif_rx(skb);
564 				++dev->stats.rx_packets;
565 			}
566 		}
567 	}
568 	yp->rx_len = 0;
569 	yp->rx_crcl = 0x21;
570 	yp->rx_crch = 0xf3;
571 }
572 
573 static inline void yam_rx_byte(struct net_device *dev, struct yam_port *yp, unsigned char rxb)
574 {
575 	if (yp->rx_len < YAM_MAX_FRAME) {
576 		unsigned char c = yp->rx_crcl;
577 		yp->rx_crcl = (chktabl[c] ^ yp->rx_crch);
578 		yp->rx_crch = (chktabh[c] ^ rxb);
579 		yp->rx_buf[yp->rx_len++] = rxb;
580 	}
581 }
582 
583 /********************************************************************************
584 * TX Section
585 ********************************************************************************/
586 
587 static void ptt_on(struct net_device *dev)
588 {
589 	outb(PTT_ON, MCR(dev->base_addr));
590 }
591 
592 static void ptt_off(struct net_device *dev)
593 {
594 	outb(PTT_OFF, MCR(dev->base_addr));
595 }
596 
597 static netdev_tx_t yam_send_packet(struct sk_buff *skb,
598 					 struct net_device *dev)
599 {
600 	struct yam_port *yp = netdev_priv(dev);
601 
602 	skb_queue_tail(&yp->send_queue, skb);
603 	dev->trans_start = jiffies;
604 	return NETDEV_TX_OK;
605 }
606 
607 static void yam_start_tx(struct net_device *dev, struct yam_port *yp)
608 {
609 	if ((yp->tx_state == TX_TAIL) || (yp->txd == 0))
610 		yp->tx_count = 1;
611 	else
612 		yp->tx_count = (yp->bitrate * yp->txd) / 8000;
613 	yp->tx_state = TX_HEAD;
614 	ptt_on(dev);
615 }
616 
617 static void yam_arbitrate(struct net_device *dev)
618 {
619 	struct yam_port *yp = netdev_priv(dev);
620 
621 	if (yp->magic != YAM_MAGIC || yp->tx_state != TX_OFF ||
622 	    skb_queue_empty(&yp->send_queue))
623 		return;
624 	/* tx_state is TX_OFF and there is data to send */
625 
626 	if (yp->dupmode) {
627 		/* Full duplex mode, don't wait */
628 		yam_start_tx(dev, yp);
629 		return;
630 	}
631 	if (yp->dcd) {
632 		/* DCD on, wait slotime ... */
633 		yp->slotcnt = yp->slot / 10;
634 		return;
635 	}
636 	/* Is slottime passed ? */
637 	if ((--yp->slotcnt) > 0)
638 		return;
639 
640 	yp->slotcnt = yp->slot / 10;
641 
642 	/* is random > persist ? */
643 	if ((random32() % 256) > yp->pers)
644 		return;
645 
646 	yam_start_tx(dev, yp);
647 }
648 
649 static void yam_dotimer(unsigned long dummy)
650 {
651 	int i;
652 
653 	for (i = 0; i < NR_PORTS; i++) {
654 		struct net_device *dev = yam_devs[i];
655 		if (dev && netif_running(dev))
656 			yam_arbitrate(dev);
657 	}
658 	yam_timer.expires = jiffies + HZ / 100;
659 	add_timer(&yam_timer);
660 }
661 
662 static void yam_tx_byte(struct net_device *dev, struct yam_port *yp)
663 {
664 	struct sk_buff *skb;
665 	unsigned char b, temp;
666 
667 	switch (yp->tx_state) {
668 	case TX_OFF:
669 		break;
670 	case TX_HEAD:
671 		if (--yp->tx_count <= 0) {
672 			if (!(skb = skb_dequeue(&yp->send_queue))) {
673 				ptt_off(dev);
674 				yp->tx_state = TX_OFF;
675 				break;
676 			}
677 			yp->tx_state = TX_DATA;
678 			if (skb->data[0] != 0) {
679 /*                              do_kiss_params(s, skb->data, skb->len); */
680 				dev_kfree_skb_any(skb);
681 				break;
682 			}
683 			yp->tx_len = skb->len - 1;	/* strip KISS byte */
684 			if (yp->tx_len >= YAM_MAX_FRAME || yp->tx_len < 2) {
685         			dev_kfree_skb_any(skb);
686 				break;
687 			}
688 			skb_copy_from_linear_data_offset(skb, 1,
689 							 yp->tx_buf,
690 							 yp->tx_len);
691 			dev_kfree_skb_any(skb);
692 			yp->tx_count = 0;
693 			yp->tx_crcl = 0x21;
694 			yp->tx_crch = 0xf3;
695 			yp->tx_state = TX_DATA;
696 		}
697 		break;
698 	case TX_DATA:
699 		b = yp->tx_buf[yp->tx_count++];
700 		outb(b, THR(dev->base_addr));
701 		temp = yp->tx_crcl;
702 		yp->tx_crcl = chktabl[temp] ^ yp->tx_crch;
703 		yp->tx_crch = chktabh[temp] ^ b;
704 		if (yp->tx_count >= yp->tx_len) {
705 			yp->tx_state = TX_CRC1;
706 		}
707 		break;
708 	case TX_CRC1:
709 		yp->tx_crch = chktabl[yp->tx_crcl] ^ yp->tx_crch;
710 		yp->tx_crcl = chktabh[yp->tx_crcl] ^ chktabl[yp->tx_crch] ^ 0xff;
711 		outb(yp->tx_crcl, THR(dev->base_addr));
712 		yp->tx_state = TX_CRC2;
713 		break;
714 	case TX_CRC2:
715 		outb(chktabh[yp->tx_crch] ^ 0xFF, THR(dev->base_addr));
716 		if (skb_queue_empty(&yp->send_queue)) {
717 			yp->tx_count = (yp->bitrate * yp->txtail) / 8000;
718 			if (yp->dupmode == 2)
719 				yp->tx_count += (yp->bitrate * yp->holdd) / 8;
720 			if (yp->tx_count == 0)
721 				yp->tx_count = 1;
722 			yp->tx_state = TX_TAIL;
723 		} else {
724 			yp->tx_count = 1;
725 			yp->tx_state = TX_HEAD;
726 		}
727 		++dev->stats.tx_packets;
728 		break;
729 	case TX_TAIL:
730 		if (--yp->tx_count <= 0) {
731 			yp->tx_state = TX_OFF;
732 			ptt_off(dev);
733 		}
734 		break;
735 	}
736 }
737 
738 /***********************************************************************************
739 * ISR routine
740 ************************************************************************************/
741 
742 static irqreturn_t yam_interrupt(int irq, void *dev_id)
743 {
744 	struct net_device *dev;
745 	struct yam_port *yp;
746 	unsigned char iir;
747 	int counter = 100;
748 	int i;
749 	int handled = 0;
750 
751 	for (i = 0; i < NR_PORTS; i++) {
752 		dev = yam_devs[i];
753 		yp = netdev_priv(dev);
754 
755 		if (!netif_running(dev))
756 			continue;
757 
758 		while ((iir = IIR_MASK & inb(IIR(dev->base_addr))) != IIR_NOPEND) {
759 			unsigned char msr = inb(MSR(dev->base_addr));
760 			unsigned char lsr = inb(LSR(dev->base_addr));
761 			unsigned char rxb;
762 
763 			handled = 1;
764 
765 			if (lsr & LSR_OE)
766 				++dev->stats.rx_fifo_errors;
767 
768 			yp->dcd = (msr & RX_DCD) ? 1 : 0;
769 
770 			if (--counter <= 0) {
771 				printk(KERN_ERR "%s: too many irq iir=%d\n",
772 						dev->name, iir);
773 				goto out;
774 			}
775 			if (msr & TX_RDY) {
776 				++yp->nb_mdint;
777 				yam_tx_byte(dev, yp);
778 			}
779 			if (lsr & LSR_RXC) {
780 				++yp->nb_rxint;
781 				rxb = inb(RBR(dev->base_addr));
782 				if (msr & RX_FLAG)
783 					yam_rx_flag(dev, yp);
784 				else
785 					yam_rx_byte(dev, yp, rxb);
786 			}
787 		}
788 	}
789 out:
790 	return IRQ_RETVAL(handled);
791 }
792 
793 #ifdef CONFIG_PROC_FS
794 
795 static void *yam_seq_start(struct seq_file *seq, loff_t *pos)
796 {
797 	return (*pos < NR_PORTS) ? yam_devs[*pos] : NULL;
798 }
799 
800 static void *yam_seq_next(struct seq_file *seq, void *v, loff_t *pos)
801 {
802 	++*pos;
803 	return (*pos < NR_PORTS) ? yam_devs[*pos] : NULL;
804 }
805 
806 static void yam_seq_stop(struct seq_file *seq, void *v)
807 {
808 }
809 
810 static int yam_seq_show(struct seq_file *seq, void *v)
811 {
812 	struct net_device *dev = v;
813 	const struct yam_port *yp = netdev_priv(dev);
814 
815 	seq_printf(seq, "Device %s\n", dev->name);
816 	seq_printf(seq, "  Up       %d\n", netif_running(dev));
817 	seq_printf(seq, "  Speed    %u\n", yp->bitrate);
818 	seq_printf(seq, "  IoBase   0x%x\n", yp->iobase);
819 	seq_printf(seq, "  BaudRate %u\n", yp->baudrate);
820 	seq_printf(seq, "  IRQ      %u\n", yp->irq);
821 	seq_printf(seq, "  TxState  %u\n", yp->tx_state);
822 	seq_printf(seq, "  Duplex   %u\n", yp->dupmode);
823 	seq_printf(seq, "  HoldDly  %u\n", yp->holdd);
824 	seq_printf(seq, "  TxDelay  %u\n", yp->txd);
825 	seq_printf(seq, "  TxTail   %u\n", yp->txtail);
826 	seq_printf(seq, "  SlotTime %u\n", yp->slot);
827 	seq_printf(seq, "  Persist  %u\n", yp->pers);
828 	seq_printf(seq, "  TxFrames %lu\n", dev->stats.tx_packets);
829 	seq_printf(seq, "  RxFrames %lu\n", dev->stats.rx_packets);
830 	seq_printf(seq, "  TxInt    %u\n", yp->nb_mdint);
831 	seq_printf(seq, "  RxInt    %u\n", yp->nb_rxint);
832 	seq_printf(seq, "  RxOver   %lu\n", dev->stats.rx_fifo_errors);
833 	seq_printf(seq, "\n");
834 	return 0;
835 }
836 
837 static const struct seq_operations yam_seqops = {
838 	.start = yam_seq_start,
839 	.next = yam_seq_next,
840 	.stop = yam_seq_stop,
841 	.show = yam_seq_show,
842 };
843 
844 static int yam_info_open(struct inode *inode, struct file *file)
845 {
846 	return seq_open(file, &yam_seqops);
847 }
848 
849 static const struct file_operations yam_info_fops = {
850 	.owner = THIS_MODULE,
851 	.open = yam_info_open,
852 	.read = seq_read,
853 	.llseek = seq_lseek,
854 	.release = seq_release,
855 };
856 
857 #endif
858 
859 
860 /* --------------------------------------------------------------------- */
861 
862 static int yam_open(struct net_device *dev)
863 {
864 	struct yam_port *yp = netdev_priv(dev);
865 	enum uart u;
866 	int i;
867 	int ret=0;
868 
869 	printk(KERN_INFO "Trying %s at iobase 0x%lx irq %u\n", dev->name, dev->base_addr, dev->irq);
870 
871 	if (!dev || !yp->bitrate)
872 		return -ENXIO;
873 	if (!dev->base_addr || dev->base_addr > 0x1000 - YAM_EXTENT ||
874 		dev->irq < 2 || dev->irq > 15) {
875 		return -ENXIO;
876 	}
877 	if (!request_region(dev->base_addr, YAM_EXTENT, dev->name))
878 	{
879 		printk(KERN_ERR "%s: cannot 0x%lx busy\n", dev->name, dev->base_addr);
880 		return -EACCES;
881 	}
882 	if ((u = yam_check_uart(dev->base_addr)) == c_uart_unknown) {
883 		printk(KERN_ERR "%s: cannot find uart type\n", dev->name);
884 		ret = -EIO;
885 		goto out_release_base;
886 	}
887 	if (fpga_download(dev->base_addr, yp->bitrate)) {
888 		printk(KERN_ERR "%s: cannot init FPGA\n", dev->name);
889 		ret = -EIO;
890 		goto out_release_base;
891 	}
892 	outb(0, IER(dev->base_addr));
893 	if (request_irq(dev->irq, yam_interrupt, IRQF_DISABLED | IRQF_SHARED, dev->name, dev)) {
894 		printk(KERN_ERR "%s: irq %d busy\n", dev->name, dev->irq);
895 		ret = -EBUSY;
896 		goto out_release_base;
897 	}
898 
899 	yam_set_uart(dev);
900 
901 	netif_start_queue(dev);
902 
903 	yp->slotcnt = yp->slot / 10;
904 
905 	/* Reset overruns for all ports - FPGA programming makes overruns */
906 	for (i = 0; i < NR_PORTS; i++) {
907 		struct net_device *yam_dev = yam_devs[i];
908 
909 		inb(LSR(yam_dev->base_addr));
910 		yam_dev->stats.rx_fifo_errors = 0;
911 	}
912 
913 	printk(KERN_INFO "%s at iobase 0x%lx irq %u uart %s\n", dev->name, dev->base_addr, dev->irq,
914 		   uart_str[u]);
915 	return 0;
916 
917 out_release_base:
918 	release_region(dev->base_addr, YAM_EXTENT);
919 	return ret;
920 }
921 
922 /* --------------------------------------------------------------------- */
923 
924 static int yam_close(struct net_device *dev)
925 {
926 	struct sk_buff *skb;
927 	struct yam_port *yp = netdev_priv(dev);
928 
929 	if (!dev)
930 		return -EINVAL;
931 
932 	/*
933 	 * disable interrupts
934 	 */
935 	outb(0, IER(dev->base_addr));
936 	outb(1, MCR(dev->base_addr));
937 	/* Remove IRQ handler if last */
938 	free_irq(dev->irq,dev);
939 	release_region(dev->base_addr, YAM_EXTENT);
940 	netif_stop_queue(dev);
941 	while ((skb = skb_dequeue(&yp->send_queue)))
942 		dev_kfree_skb(skb);
943 
944 	printk(KERN_INFO "%s: close yam at iobase 0x%lx irq %u\n",
945 		   yam_drvname, dev->base_addr, dev->irq);
946 	return 0;
947 }
948 
949 /* --------------------------------------------------------------------- */
950 
951 static int yam_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
952 {
953 	struct yam_port *yp = netdev_priv(dev);
954 	struct yamdrv_ioctl_cfg yi;
955 	struct yamdrv_ioctl_mcs *ym;
956 	int ioctl_cmd;
957 
958 	if (copy_from_user(&ioctl_cmd, ifr->ifr_data, sizeof(int)))
959 		 return -EFAULT;
960 
961 	if (yp->magic != YAM_MAGIC)
962 		return -EINVAL;
963 
964 	if (!capable(CAP_NET_ADMIN))
965 		return -EPERM;
966 
967 	if (cmd != SIOCDEVPRIVATE)
968 		return -EINVAL;
969 
970 	switch (ioctl_cmd) {
971 
972 	case SIOCYAMRESERVED:
973 		return -EINVAL;			/* unused */
974 
975 	case SIOCYAMSMCS:
976 		if (netif_running(dev))
977 			return -EINVAL;		/* Cannot change this parameter when up */
978 		if ((ym = kmalloc(sizeof(struct yamdrv_ioctl_mcs), GFP_KERNEL)) == NULL)
979 			return -ENOBUFS;
980 		ym->bitrate = 9600;
981 		if (copy_from_user(ym, ifr->ifr_data, sizeof(struct yamdrv_ioctl_mcs))) {
982 			kfree(ym);
983 			return -EFAULT;
984 		}
985 		if (ym->bitrate > YAM_MAXBITRATE) {
986 			kfree(ym);
987 			return -EINVAL;
988 		}
989 		/* setting predef as 0 for loading userdefined mcs data */
990 		add_mcs(ym->bits, ym->bitrate, 0);
991 		kfree(ym);
992 		break;
993 
994 	case SIOCYAMSCFG:
995 		if (!capable(CAP_SYS_RAWIO))
996 			return -EPERM;
997 		if (copy_from_user(&yi, ifr->ifr_data, sizeof(struct yamdrv_ioctl_cfg)))
998 			 return -EFAULT;
999 
1000 		if ((yi.cfg.mask & YAM_IOBASE) && netif_running(dev))
1001 			return -EINVAL;		/* Cannot change this parameter when up */
1002 		if ((yi.cfg.mask & YAM_IRQ) && netif_running(dev))
1003 			return -EINVAL;		/* Cannot change this parameter when up */
1004 		if ((yi.cfg.mask & YAM_BITRATE) && netif_running(dev))
1005 			return -EINVAL;		/* Cannot change this parameter when up */
1006 		if ((yi.cfg.mask & YAM_BAUDRATE) && netif_running(dev))
1007 			return -EINVAL;		/* Cannot change this parameter when up */
1008 
1009 		if (yi.cfg.mask & YAM_IOBASE) {
1010 			yp->iobase = yi.cfg.iobase;
1011 			dev->base_addr = yi.cfg.iobase;
1012 		}
1013 		if (yi.cfg.mask & YAM_IRQ) {
1014 			if (yi.cfg.irq > 15)
1015 				return -EINVAL;
1016 			yp->irq = yi.cfg.irq;
1017 			dev->irq = yi.cfg.irq;
1018 		}
1019 		if (yi.cfg.mask & YAM_BITRATE) {
1020 			if (yi.cfg.bitrate > YAM_MAXBITRATE)
1021 				return -EINVAL;
1022 			yp->bitrate = yi.cfg.bitrate;
1023 		}
1024 		if (yi.cfg.mask & YAM_BAUDRATE) {
1025 			if (yi.cfg.baudrate > YAM_MAXBAUDRATE)
1026 				return -EINVAL;
1027 			yp->baudrate = yi.cfg.baudrate;
1028 		}
1029 		if (yi.cfg.mask & YAM_MODE) {
1030 			if (yi.cfg.mode > YAM_MAXMODE)
1031 				return -EINVAL;
1032 			yp->dupmode = yi.cfg.mode;
1033 		}
1034 		if (yi.cfg.mask & YAM_HOLDDLY) {
1035 			if (yi.cfg.holddly > YAM_MAXHOLDDLY)
1036 				return -EINVAL;
1037 			yp->holdd = yi.cfg.holddly;
1038 		}
1039 		if (yi.cfg.mask & YAM_TXDELAY) {
1040 			if (yi.cfg.txdelay > YAM_MAXTXDELAY)
1041 				return -EINVAL;
1042 			yp->txd = yi.cfg.txdelay;
1043 		}
1044 		if (yi.cfg.mask & YAM_TXTAIL) {
1045 			if (yi.cfg.txtail > YAM_MAXTXTAIL)
1046 				return -EINVAL;
1047 			yp->txtail = yi.cfg.txtail;
1048 		}
1049 		if (yi.cfg.mask & YAM_PERSIST) {
1050 			if (yi.cfg.persist > YAM_MAXPERSIST)
1051 				return -EINVAL;
1052 			yp->pers = yi.cfg.persist;
1053 		}
1054 		if (yi.cfg.mask & YAM_SLOTTIME) {
1055 			if (yi.cfg.slottime > YAM_MAXSLOTTIME)
1056 				return -EINVAL;
1057 			yp->slot = yi.cfg.slottime;
1058 			yp->slotcnt = yp->slot / 10;
1059 		}
1060 		break;
1061 
1062 	case SIOCYAMGCFG:
1063 		yi.cfg.mask = 0xffffffff;
1064 		yi.cfg.iobase = yp->iobase;
1065 		yi.cfg.irq = yp->irq;
1066 		yi.cfg.bitrate = yp->bitrate;
1067 		yi.cfg.baudrate = yp->baudrate;
1068 		yi.cfg.mode = yp->dupmode;
1069 		yi.cfg.txdelay = yp->txd;
1070 		yi.cfg.holddly = yp->holdd;
1071 		yi.cfg.txtail = yp->txtail;
1072 		yi.cfg.persist = yp->pers;
1073 		yi.cfg.slottime = yp->slot;
1074 		if (copy_to_user(ifr->ifr_data, &yi, sizeof(struct yamdrv_ioctl_cfg)))
1075 			 return -EFAULT;
1076 		break;
1077 
1078 	default:
1079 		return -EINVAL;
1080 
1081 	}
1082 
1083 	return 0;
1084 }
1085 
1086 /* --------------------------------------------------------------------- */
1087 
1088 static int yam_set_mac_address(struct net_device *dev, void *addr)
1089 {
1090 	struct sockaddr *sa = (struct sockaddr *) addr;
1091 
1092 	/* addr is an AX.25 shifted ASCII mac address */
1093 	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
1094 	return 0;
1095 }
1096 
1097 /* --------------------------------------------------------------------- */
1098 
1099 static const struct net_device_ops yam_netdev_ops = {
1100 	.ndo_open	     = yam_open,
1101 	.ndo_stop	     = yam_close,
1102 	.ndo_start_xmit      = yam_send_packet,
1103 	.ndo_do_ioctl 	     = yam_ioctl,
1104 	.ndo_set_mac_address = yam_set_mac_address,
1105 };
1106 
1107 static void yam_setup(struct net_device *dev)
1108 {
1109 	struct yam_port *yp = netdev_priv(dev);
1110 
1111 	yp->magic = YAM_MAGIC;
1112 	yp->bitrate = DEFAULT_BITRATE;
1113 	yp->baudrate = DEFAULT_BITRATE * 2;
1114 	yp->iobase = 0;
1115 	yp->irq = 0;
1116 	yp->dupmode = 0;
1117 	yp->holdd = DEFAULT_HOLDD;
1118 	yp->txd = DEFAULT_TXD;
1119 	yp->txtail = DEFAULT_TXTAIL;
1120 	yp->slot = DEFAULT_SLOT;
1121 	yp->pers = DEFAULT_PERS;
1122 	yp->dev = dev;
1123 
1124 	dev->base_addr = yp->iobase;
1125 	dev->irq = yp->irq;
1126 
1127 	skb_queue_head_init(&yp->send_queue);
1128 
1129 	dev->netdev_ops = &yam_netdev_ops;
1130 	dev->header_ops = &ax25_header_ops;
1131 
1132 	dev->type = ARPHRD_AX25;
1133 	dev->hard_header_len = AX25_MAX_HEADER_LEN;
1134 	dev->mtu = AX25_MTU;
1135 	dev->addr_len = AX25_ADDR_LEN;
1136 	memcpy(dev->broadcast, &ax25_bcast, AX25_ADDR_LEN);
1137 	memcpy(dev->dev_addr, &ax25_defaddr, AX25_ADDR_LEN);
1138 }
1139 
1140 static int __init yam_init_driver(void)
1141 {
1142 	struct net_device *dev;
1143 	int i, err;
1144 	char name[IFNAMSIZ];
1145 
1146 	printk(yam_drvinfo);
1147 
1148 	for (i = 0; i < NR_PORTS; i++) {
1149 		sprintf(name, "yam%d", i);
1150 
1151 		dev = alloc_netdev(sizeof(struct yam_port), name,
1152 				   yam_setup);
1153 		if (!dev) {
1154 			pr_err("yam: cannot allocate net device\n");
1155 			err = -ENOMEM;
1156 			goto error;
1157 		}
1158 
1159 		err = register_netdev(dev);
1160 		if (err) {
1161 			printk(KERN_WARNING "yam: cannot register net device %s\n", dev->name);
1162 			goto error;
1163 		}
1164 		yam_devs[i] = dev;
1165 
1166 	}
1167 
1168 	yam_timer.function = yam_dotimer;
1169 	yam_timer.expires = jiffies + HZ / 100;
1170 	add_timer(&yam_timer);
1171 
1172 	proc_net_fops_create(&init_net, "yam", S_IRUGO, &yam_info_fops);
1173 	return 0;
1174  error:
1175 	while (--i >= 0) {
1176 		unregister_netdev(yam_devs[i]);
1177 		free_netdev(yam_devs[i]);
1178 	}
1179 	return err;
1180 }
1181 
1182 /* --------------------------------------------------------------------- */
1183 
1184 static void __exit yam_cleanup_driver(void)
1185 {
1186 	struct yam_mcs *p;
1187 	int i;
1188 
1189 	del_timer(&yam_timer);
1190 	for (i = 0; i < NR_PORTS; i++) {
1191 		struct net_device *dev = yam_devs[i];
1192 		if (dev) {
1193 			unregister_netdev(dev);
1194 			free_netdev(dev);
1195 		}
1196 	}
1197 
1198 	while (yam_data) {
1199 		p = yam_data;
1200 		yam_data = yam_data->next;
1201 		kfree(p);
1202 	}
1203 
1204 	proc_net_remove(&init_net, "yam");
1205 }
1206 
1207 /* --------------------------------------------------------------------- */
1208 
1209 MODULE_AUTHOR("Frederic Rible F1OAT frible@teaser.fr");
1210 MODULE_DESCRIPTION("Yam amateur radio modem driver");
1211 MODULE_LICENSE("GPL");
1212 MODULE_FIRMWARE(FIRMWARE_1200);
1213 MODULE_FIRMWARE(FIRMWARE_9600);
1214 
1215 module_init(yam_init_driver);
1216 module_exit(yam_cleanup_driver);
1217 
1218 /* --------------------------------------------------------------------- */
1219 
1220