1// SPDX-License-Identifier: GPL-2.0-or-later
2/*****************************************************************************/
3
4/*
5 *    yam.c  -- YAM radio modem driver.
6 *
7 *      Copyright (C) 1998 Frederic Rible F1OAT (frible@teaser.fr)
8 *      Adapted from baycom.c driver written by Thomas Sailer (sailer@ife.ee.ethz.ch)
9 *
10 *  Please note that the GPL allows you to use the driver, NOT the radio.
11 *  In order to use the radio, you need a license from the communications
12 *  authority of your country.
13 *
14 *  History:
15 *   0.0 F1OAT 06.06.98  Begin of work with baycom.c source code V 0.3
16 *   0.1 F1OAT 07.06.98  Add timer polling routine for channel arbitration
17 *   0.2 F6FBB 08.06.98  Added delay after FPGA programming
18 *   0.3 F6FBB 29.07.98  Delayed PTT implementation for dupmode=2
19 *   0.4 F6FBB 30.07.98  Added TxTail, Slottime and Persistence
20 *   0.5 F6FBB 01.08.98  Shared IRQs, /proc/net and network statistics
21 *   0.6 F6FBB 25.08.98  Added 1200Bds format
22 *   0.7 F6FBB 12.09.98  Added to the kernel configuration
23 *   0.8 F6FBB 14.10.98  Fixed slottime/persistence timing bug
24 *       OK1ZIA 2.09.01  Fixed "kfree_skb on hard IRQ"
25 *                       using dev_kfree_skb_any(). (important in 2.4 kernel)
26 */
27
28/*****************************************************************************/
29
30#include <linux/module.h>
31#include <linux/types.h>
32#include <linux/net.h>
33#include <linux/in.h>
34#include <linux/if.h>
35#include <linux/slab.h>
36#include <linux/errno.h>
37#include <linux/bitops.h>
38#include <linux/random.h>
39#include <asm/io.h>
40#include <linux/interrupt.h>
41#include <linux/ioport.h>
42#include <linux/firmware.h>
43#include <linux/platform_device.h>
44
45#include <linux/netdevice.h>
46#include <linux/if_arp.h>
47#include <linux/etherdevice.h>
48#include <linux/skbuff.h>
49#include <net/ax25.h>
50
51#include <linux/kernel.h>
52#include <linux/proc_fs.h>
53#include <linux/seq_file.h>
54#include <net/net_namespace.h>
55
56#include <linux/uaccess.h>
57#include <linux/init.h>
58
59#include <linux/yam.h>
60
61/* --------------------------------------------------------------------- */
62
63static const char yam_drvname[] = "yam";
64static const char yam_drvinfo[] __initconst = KERN_INFO \
65	"YAM driver version 0.8 by F1OAT/F6FBB\n";
66
67/* --------------------------------------------------------------------- */
68
69#define FIRMWARE_9600	"yam/9600.bin"
70#define FIRMWARE_1200	"yam/1200.bin"
71
72#define YAM_9600	1
73#define YAM_1200	2
74
75#define NR_PORTS	4
76#define YAM_MAGIC	0xF10A7654
77
78/* Transmitter states */
79
80#define TX_OFF		0
81#define TX_HEAD		1
82#define TX_DATA		2
83#define TX_CRC1		3
84#define TX_CRC2		4
85#define TX_TAIL		5
86
87#define YAM_MAX_FRAME	1024
88
89#define DEFAULT_BITRATE	9600			/* bps */
90#define DEFAULT_HOLDD	10			/* sec */
91#define DEFAULT_TXD	300			/* ms */
92#define DEFAULT_TXTAIL	10			/* ms */
93#define DEFAULT_SLOT	100			/* ms */
94#define DEFAULT_PERS	64			/* 0->255 */
95
96struct yam_port {
97	int magic;
98	int bitrate;
99	int baudrate;
100	int iobase;
101	int irq;
102	int dupmode;
103
104	struct net_device *dev;
105
106	int nb_rxint;
107	int nb_mdint;
108
109	/* Parameters section */
110
111	int txd;				/* tx delay */
112	int holdd;				/* duplex ptt delay */
113	int txtail;				/* txtail delay */
114	int slot;				/* slottime */
115	int pers;				/* persistence */
116
117	/* Tx section */
118
119	int tx_state;
120	int tx_count;
121	int slotcnt;
122	unsigned char tx_buf[YAM_MAX_FRAME];
123	int tx_len;
124	int tx_crcl, tx_crch;
125	struct sk_buff_head send_queue;		/* Packets awaiting transmission */
126
127	/* Rx section */
128
129	int dcd;
130	unsigned char rx_buf[YAM_MAX_FRAME];
131	int rx_len;
132	int rx_crcl, rx_crch;
133};
134
135struct yam_mcs {
136	unsigned char bits[YAM_FPGA_SIZE];
137	int bitrate;
138	struct yam_mcs *next;
139};
140
141static struct net_device *yam_devs[NR_PORTS];
142
143static struct yam_mcs *yam_data;
144
145static DEFINE_TIMER(yam_timer, NULL);
146
147/* --------------------------------------------------------------------- */
148
149#define RBR(iobase)	(iobase+0)
150#define THR(iobase)	(iobase+0)
151#define IER(iobase)	(iobase+1)
152#define IIR(iobase)	(iobase+2)
153#define FCR(iobase)	(iobase+2)
154#define LCR(iobase)	(iobase+3)
155#define MCR(iobase)	(iobase+4)
156#define LSR(iobase)	(iobase+5)
157#define MSR(iobase)	(iobase+6)
158#define SCR(iobase)	(iobase+7)
159#define DLL(iobase)	(iobase+0)
160#define DLM(iobase)	(iobase+1)
161
162#define YAM_EXTENT	8
163
164/* Interrupt Identification Register Bit Masks */
165#define IIR_NOPEND	1
166#define IIR_MSR		0
167#define IIR_TX		2
168#define IIR_RX		4
169#define IIR_LSR		6
170#define IIR_TIMEOUT	12			/* Fifo mode only */
171
172#define IIR_MASK	0x0F
173
174/* Interrupt Enable Register Bit Masks */
175#define IER_RX		1			/* enable rx interrupt */
176#define IER_TX		2			/* enable tx interrupt */
177#define IER_LSR		4			/* enable line status interrupts */
178#define IER_MSR		8			/* enable modem status interrupts */
179
180/* Modem Control Register Bit Masks */
181#define MCR_DTR		0x01			/* DTR output */
182#define MCR_RTS		0x02			/* RTS output */
183#define MCR_OUT1	0x04			/* OUT1 output (not accessible in RS232) */
184#define MCR_OUT2	0x08			/* Master Interrupt enable (must be set on PCs) */
185#define MCR_LOOP	0x10			/* Loopback enable */
186
187/* Modem Status Register Bit Masks */
188#define MSR_DCTS	0x01			/* Delta CTS input */
189#define MSR_DDSR	0x02			/* Delta DSR */
190#define MSR_DRIN	0x04			/* Delta RI */
191#define MSR_DDCD	0x08			/* Delta DCD */
192#define MSR_CTS		0x10			/* CTS input */
193#define MSR_DSR		0x20			/* DSR input */
194#define MSR_RING	0x40			/* RI  input */
195#define MSR_DCD		0x80			/* DCD input */
196
197/* line status register bit mask */
198#define LSR_RXC		0x01
199#define LSR_OE		0x02
200#define LSR_PE		0x04
201#define LSR_FE		0x08
202#define LSR_BREAK	0x10
203#define LSR_THRE	0x20
204#define LSR_TSRE	0x40
205
206/* Line Control Register Bit Masks */
207#define LCR_DLAB	0x80
208#define LCR_BREAK	0x40
209#define LCR_PZERO	0x28
210#define LCR_PEVEN	0x18
211#define LCR_PODD	0x08
212#define LCR_STOP1	0x00
213#define LCR_STOP2	0x04
214#define LCR_BIT5	0x00
215#define LCR_BIT6	0x02
216#define LCR_BIT7	0x01
217#define LCR_BIT8	0x03
218
219/* YAM Modem <-> UART Port mapping */
220
221#define TX_RDY		MSR_DCTS		/* transmitter ready to send */
222#define RX_DCD		MSR_DCD			/* carrier detect */
223#define RX_FLAG		MSR_RING		/* hdlc flag received */
224#define FPGA_DONE	MSR_DSR			/* FPGA is configured */
225#define PTT_ON		(MCR_RTS|MCR_OUT2)	/* activate PTT */
226#define PTT_OFF		(MCR_DTR|MCR_OUT2)	/* release PTT */
227
228#define ENABLE_RXINT	IER_RX			/* enable uart rx interrupt during rx */
229#define ENABLE_TXINT	IER_MSR			/* enable uart ms interrupt during tx */
230#define ENABLE_RTXINT	(IER_RX|IER_MSR)	/* full duplex operations */
231
232
233/*************************************************************************
234* CRC Tables
235************************************************************************/
236
237static const unsigned char chktabl[256] =
238{0x00, 0x89, 0x12, 0x9b, 0x24, 0xad, 0x36, 0xbf, 0x48, 0xc1, 0x5a, 0xd3, 0x6c, 0xe5, 0x7e,
239 0xf7, 0x81, 0x08, 0x93, 0x1a, 0xa5, 0x2c, 0xb7, 0x3e, 0xc9, 0x40, 0xdb, 0x52, 0xed, 0x64,
240 0xff, 0x76, 0x02, 0x8b, 0x10, 0x99, 0x26, 0xaf, 0x34, 0xbd, 0x4a, 0xc3, 0x58, 0xd1, 0x6e,
241 0xe7, 0x7c, 0xf5, 0x83, 0x0a, 0x91, 0x18, 0xa7, 0x2e, 0xb5, 0x3c, 0xcb, 0x42, 0xd9, 0x50,
242 0xef, 0x66, 0xfd, 0x74, 0x04, 0x8d, 0x16, 0x9f, 0x20, 0xa9, 0x32, 0xbb, 0x4c, 0xc5, 0x5e,
243 0xd7, 0x68, 0xe1, 0x7a, 0xf3, 0x85, 0x0c, 0x97, 0x1e, 0xa1, 0x28, 0xb3, 0x3a, 0xcd, 0x44,
244 0xdf, 0x56, 0xe9, 0x60, 0xfb, 0x72, 0x06, 0x8f, 0x14, 0x9d, 0x22, 0xab, 0x30, 0xb9, 0x4e,
245 0xc7, 0x5c, 0xd5, 0x6a, 0xe3, 0x78, 0xf1, 0x87, 0x0e, 0x95, 0x1c, 0xa3, 0x2a, 0xb1, 0x38,
246 0xcf, 0x46, 0xdd, 0x54, 0xeb, 0x62, 0xf9, 0x70, 0x08, 0x81, 0x1a, 0x93, 0x2c, 0xa5, 0x3e,
247 0xb7, 0x40, 0xc9, 0x52, 0xdb, 0x64, 0xed, 0x76, 0xff, 0x89, 0x00, 0x9b, 0x12, 0xad, 0x24,
248 0xbf, 0x36, 0xc1, 0x48, 0xd3, 0x5a, 0xe5, 0x6c, 0xf7, 0x7e, 0x0a, 0x83, 0x18, 0x91, 0x2e,
249 0xa7, 0x3c, 0xb5, 0x42, 0xcb, 0x50, 0xd9, 0x66, 0xef, 0x74, 0xfd, 0x8b, 0x02, 0x99, 0x10,
250 0xaf, 0x26, 0xbd, 0x34, 0xc3, 0x4a, 0xd1, 0x58, 0xe7, 0x6e, 0xf5, 0x7c, 0x0c, 0x85, 0x1e,
251 0x97, 0x28, 0xa1, 0x3a, 0xb3, 0x44, 0xcd, 0x56, 0xdf, 0x60, 0xe9, 0x72, 0xfb, 0x8d, 0x04,
252 0x9f, 0x16, 0xa9, 0x20, 0xbb, 0x32, 0xc5, 0x4c, 0xd7, 0x5e, 0xe1, 0x68, 0xf3, 0x7a, 0x0e,
253 0x87, 0x1c, 0x95, 0x2a, 0xa3, 0x38, 0xb1, 0x46, 0xcf, 0x54, 0xdd, 0x62, 0xeb, 0x70, 0xf9,
254 0x8f, 0x06, 0x9d, 0x14, 0xab, 0x22, 0xb9, 0x30, 0xc7, 0x4e, 0xd5, 0x5c, 0xe3, 0x6a, 0xf1,
255 0x78};
256static const unsigned char chktabh[256] =
257{0x00, 0x11, 0x23, 0x32, 0x46, 0x57, 0x65, 0x74, 0x8c, 0x9d, 0xaf, 0xbe, 0xca, 0xdb, 0xe9,
258 0xf8, 0x10, 0x01, 0x33, 0x22, 0x56, 0x47, 0x75, 0x64, 0x9c, 0x8d, 0xbf, 0xae, 0xda, 0xcb,
259 0xf9, 0xe8, 0x21, 0x30, 0x02, 0x13, 0x67, 0x76, 0x44, 0x55, 0xad, 0xbc, 0x8e, 0x9f, 0xeb,
260 0xfa, 0xc8, 0xd9, 0x31, 0x20, 0x12, 0x03, 0x77, 0x66, 0x54, 0x45, 0xbd, 0xac, 0x9e, 0x8f,
261 0xfb, 0xea, 0xd8, 0xc9, 0x42, 0x53, 0x61, 0x70, 0x04, 0x15, 0x27, 0x36, 0xce, 0xdf, 0xed,
262 0xfc, 0x88, 0x99, 0xab, 0xba, 0x52, 0x43, 0x71, 0x60, 0x14, 0x05, 0x37, 0x26, 0xde, 0xcf,
263 0xfd, 0xec, 0x98, 0x89, 0xbb, 0xaa, 0x63, 0x72, 0x40, 0x51, 0x25, 0x34, 0x06, 0x17, 0xef,
264 0xfe, 0xcc, 0xdd, 0xa9, 0xb8, 0x8a, 0x9b, 0x73, 0x62, 0x50, 0x41, 0x35, 0x24, 0x16, 0x07,
265 0xff, 0xee, 0xdc, 0xcd, 0xb9, 0xa8, 0x9a, 0x8b, 0x84, 0x95, 0xa7, 0xb6, 0xc2, 0xd3, 0xe1,
266 0xf0, 0x08, 0x19, 0x2b, 0x3a, 0x4e, 0x5f, 0x6d, 0x7c, 0x94, 0x85, 0xb7, 0xa6, 0xd2, 0xc3,
267 0xf1, 0xe0, 0x18, 0x09, 0x3b, 0x2a, 0x5e, 0x4f, 0x7d, 0x6c, 0xa5, 0xb4, 0x86, 0x97, 0xe3,
268 0xf2, 0xc0, 0xd1, 0x29, 0x38, 0x0a, 0x1b, 0x6f, 0x7e, 0x4c, 0x5d, 0xb5, 0xa4, 0x96, 0x87,
269 0xf3, 0xe2, 0xd0, 0xc1, 0x39, 0x28, 0x1a, 0x0b, 0x7f, 0x6e, 0x5c, 0x4d, 0xc6, 0xd7, 0xe5,
270 0xf4, 0x80, 0x91, 0xa3, 0xb2, 0x4a, 0x5b, 0x69, 0x78, 0x0c, 0x1d, 0x2f, 0x3e, 0xd6, 0xc7,
271 0xf5, 0xe4, 0x90, 0x81, 0xb3, 0xa2, 0x5a, 0x4b, 0x79, 0x68, 0x1c, 0x0d, 0x3f, 0x2e, 0xe7,
272 0xf6, 0xc4, 0xd5, 0xa1, 0xb0, 0x82, 0x93, 0x6b, 0x7a, 0x48, 0x59, 0x2d, 0x3c, 0x0e, 0x1f,
273 0xf7, 0xe6, 0xd4, 0xc5, 0xb1, 0xa0, 0x92, 0x83, 0x7b, 0x6a, 0x58, 0x49, 0x3d, 0x2c, 0x1e,
274 0x0f};
275
276/*************************************************************************
277* FPGA functions
278************************************************************************/
279
280static void delay(int ms)
281{
282	unsigned long timeout = jiffies + ((ms * HZ) / 1000);
283	while (time_before(jiffies, timeout))
284		cpu_relax();
285}
286
287/*
288 * reset FPGA
289 */
290
291static void fpga_reset(int iobase)
292{
293	outb(0, IER(iobase));
294	outb(LCR_DLAB | LCR_BIT5, LCR(iobase));
295	outb(1, DLL(iobase));
296	outb(0, DLM(iobase));
297
298	outb(LCR_BIT5, LCR(iobase));
299	inb(LSR(iobase));
300	inb(MSR(iobase));
301	/* turn off FPGA supply voltage */
302	outb(MCR_OUT1 | MCR_OUT2, MCR(iobase));
303	delay(100);
304	/* turn on FPGA supply voltage again */
305	outb(MCR_DTR | MCR_RTS | MCR_OUT1 | MCR_OUT2, MCR(iobase));
306	delay(100);
307}
308
309/*
310 * send one byte to FPGA
311 */
312
313static int fpga_write(int iobase, unsigned char wrd)
314{
315	unsigned char bit;
316	int k;
317	unsigned long timeout = jiffies + HZ / 10;
318
319	for (k = 0; k < 8; k++) {
320		bit = (wrd & 0x80) ? (MCR_RTS | MCR_DTR) : MCR_DTR;
321		outb(bit | MCR_OUT1 | MCR_OUT2, MCR(iobase));
322		wrd <<= 1;
323		outb(0xfc, THR(iobase));
324		while ((inb(LSR(iobase)) & LSR_TSRE) == 0)
325			if (time_after(jiffies, timeout))
326				return -1;
327	}
328
329	return 0;
330}
331
332/*
333 * predef should be 0 for loading user defined mcs
334 * predef should be YAM_1200 for loading predef 1200 mcs
335 * predef should be YAM_9600 for loading predef 9600 mcs
336 */
337static unsigned char *add_mcs(unsigned char *bits, int bitrate,
338			      unsigned int predef)
339{
340	const char *fw_name[2] = {FIRMWARE_9600, FIRMWARE_1200};
341	const struct firmware *fw;
342	struct platform_device *pdev;
343	struct yam_mcs *p;
344	int err;
345
346	switch (predef) {
347	case 0:
348		fw = NULL;
349		break;
350	case YAM_1200:
351	case YAM_9600:
352		predef--;
353		pdev = platform_device_register_simple("yam", 0, NULL, 0);
354		if (IS_ERR(pdev)) {
355			printk(KERN_ERR "yam: Failed to register firmware\n");
356			return NULL;
357		}
358		err = request_firmware(&fw, fw_name[predef], &pdev->dev);
359		platform_device_unregister(pdev);
360		if (err) {
361			printk(KERN_ERR "Failed to load firmware \"%s\"\n",
362			       fw_name[predef]);
363			return NULL;
364		}
365		if (fw->size != YAM_FPGA_SIZE) {
366			printk(KERN_ERR "Bogus length %zu in firmware \"%s\"\n",
367			       fw->size, fw_name[predef]);
368			release_firmware(fw);
369			return NULL;
370		}
371		bits = (unsigned char *)fw->data;
372		break;
373	default:
374		printk(KERN_ERR "yam: Invalid predef number %u\n", predef);
375		return NULL;
376	}
377
378	/* If it already exists, replace the bit data */
379	p = yam_data;
380	while (p) {
381		if (p->bitrate == bitrate) {
382			memcpy(p->bits, bits, YAM_FPGA_SIZE);
383			goto out;
384		}
385		p = p->next;
386	}
387
388	/* Allocate a new mcs */
389	if ((p = kmalloc(sizeof(struct yam_mcs), GFP_KERNEL)) == NULL) {
390		release_firmware(fw);
391		return NULL;
392	}
393	memcpy(p->bits, bits, YAM_FPGA_SIZE);
394	p->bitrate = bitrate;
395	p->next = yam_data;
396	yam_data = p;
397 out:
398	release_firmware(fw);
399	return p->bits;
400}
401
402static unsigned char *get_mcs(int bitrate)
403{
404	struct yam_mcs *p;
405
406	p = yam_data;
407	while (p) {
408		if (p->bitrate == bitrate)
409			return p->bits;
410		p = p->next;
411	}
412
413	/* Load predefined mcs data */
414	switch (bitrate) {
415	case 1200:
416		/* setting predef as YAM_1200 for loading predef 1200 mcs */
417		return add_mcs(NULL, bitrate, YAM_1200);
418	default:
419		/* setting predef as YAM_9600 for loading predef 9600 mcs */
420		return add_mcs(NULL, bitrate, YAM_9600);
421	}
422}
423
424/*
425 * download bitstream to FPGA
426 * data is contained in bits[] array in yam1200.h resp. yam9600.h
427 */
428
429static int fpga_download(int iobase, int bitrate)
430{
431	int i, rc;
432	unsigned char *pbits;
433
434	pbits = get_mcs(bitrate);
435	if (pbits == NULL)
436		return -1;
437
438	fpga_reset(iobase);
439	for (i = 0; i < YAM_FPGA_SIZE; i++) {
440		if (fpga_write(iobase, pbits[i])) {
441			printk(KERN_ERR "yam: error in write cycle\n");
442			return -1;			/* write... */
443		}
444	}
445
446	fpga_write(iobase, 0xFF);
447	rc = inb(MSR(iobase));		/* check DONE signal */
448
449	/* Needed for some hardwares */
450	delay(50);
451
452	return (rc & MSR_DSR) ? 0 : -1;
453}
454
455
456/************************************************************************
457* Serial port init
458************************************************************************/
459
460static void yam_set_uart(struct net_device *dev)
461{
462	struct yam_port *yp = netdev_priv(dev);
463	int divisor = 115200 / yp->baudrate;
464
465	outb(0, IER(dev->base_addr));
466	outb(LCR_DLAB | LCR_BIT8, LCR(dev->base_addr));
467	outb(divisor, DLL(dev->base_addr));
468	outb(0, DLM(dev->base_addr));
469	outb(LCR_BIT8, LCR(dev->base_addr));
470	outb(PTT_OFF, MCR(dev->base_addr));
471	outb(0x00, FCR(dev->base_addr));
472
473	/* Flush pending irq */
474
475	inb(RBR(dev->base_addr));
476	inb(MSR(dev->base_addr));
477
478	/* Enable rx irq */
479
480	outb(ENABLE_RTXINT, IER(dev->base_addr));
481}
482
483
484/* --------------------------------------------------------------------- */
485
486enum uart {
487	c_uart_unknown, c_uart_8250,
488	c_uart_16450, c_uart_16550, c_uart_16550A
489};
490
491static const char *uart_str[] =
492{"unknown", "8250", "16450", "16550", "16550A"};
493
494static enum uart yam_check_uart(unsigned int iobase)
495{
496	unsigned char b1, b2, b3;
497	enum uart u;
498	enum uart uart_tab[] =
499	{c_uart_16450, c_uart_unknown, c_uart_16550, c_uart_16550A};
500
501	b1 = inb(MCR(iobase));
502	outb(b1 | 0x10, MCR(iobase));	/* loopback mode */
503	b2 = inb(MSR(iobase));
504	outb(0x1a, MCR(iobase));
505	b3 = inb(MSR(iobase)) & 0xf0;
506	outb(b1, MCR(iobase));		/* restore old values */
507	outb(b2, MSR(iobase));
508	if (b3 != 0x90)
509		return c_uart_unknown;
510	inb(RBR(iobase));
511	inb(RBR(iobase));
512	outb(0x01, FCR(iobase));	/* enable FIFOs */
513	u = uart_tab[(inb(IIR(iobase)) >> 6) & 3];
514	if (u == c_uart_16450) {
515		outb(0x5a, SCR(iobase));
516		b1 = inb(SCR(iobase));
517		outb(0xa5, SCR(iobase));
518		b2 = inb(SCR(iobase));
519		if ((b1 != 0x5a) || (b2 != 0xa5))
520			u = c_uart_8250;
521	}
522	return u;
523}
524
525/******************************************************************************
526* Rx Section
527******************************************************************************/
528static inline void yam_rx_flag(struct net_device *dev, struct yam_port *yp)
529{
530	if (yp->dcd && yp->rx_len >= 3 && yp->rx_len < YAM_MAX_FRAME) {
531		int pkt_len = yp->rx_len - 2 + 1;	/* -CRC + kiss */
532		struct sk_buff *skb;
533
534		if ((yp->rx_crch & yp->rx_crcl) != 0xFF) {
535			/* Bad crc */
536		} else {
537			if (!(skb = dev_alloc_skb(pkt_len))) {
538				printk(KERN_WARNING "%s: memory squeeze, dropping packet\n", dev->name);
539				++dev->stats.rx_dropped;
540			} else {
541				unsigned char *cp;
542				cp = skb_put(skb, pkt_len);
543				*cp++ = 0;		/* KISS kludge */
544				memcpy(cp, yp->rx_buf, pkt_len - 1);
545				skb->protocol = ax25_type_trans(skb, dev);
546				netif_rx(skb);
547				++dev->stats.rx_packets;
548			}
549		}
550	}
551	yp->rx_len = 0;
552	yp->rx_crcl = 0x21;
553	yp->rx_crch = 0xf3;
554}
555
556static inline void yam_rx_byte(struct net_device *dev, struct yam_port *yp, unsigned char rxb)
557{
558	if (yp->rx_len < YAM_MAX_FRAME) {
559		unsigned char c = yp->rx_crcl;
560		yp->rx_crcl = (chktabl[c] ^ yp->rx_crch);
561		yp->rx_crch = (chktabh[c] ^ rxb);
562		yp->rx_buf[yp->rx_len++] = rxb;
563	}
564}
565
566/********************************************************************************
567* TX Section
568********************************************************************************/
569
570static void ptt_on(struct net_device *dev)
571{
572	outb(PTT_ON, MCR(dev->base_addr));
573}
574
575static void ptt_off(struct net_device *dev)
576{
577	outb(PTT_OFF, MCR(dev->base_addr));
578}
579
580static netdev_tx_t yam_send_packet(struct sk_buff *skb,
581					 struct net_device *dev)
582{
583	struct yam_port *yp = netdev_priv(dev);
584
585	if (skb->protocol == htons(ETH_P_IP))
586		return ax25_ip_xmit(skb);
587
588	skb_queue_tail(&yp->send_queue, skb);
589	netif_trans_update(dev);
590	return NETDEV_TX_OK;
591}
592
593static void yam_start_tx(struct net_device *dev, struct yam_port *yp)
594{
595	if ((yp->tx_state == TX_TAIL) || (yp->txd == 0))
596		yp->tx_count = 1;
597	else
598		yp->tx_count = (yp->bitrate * yp->txd) / 8000;
599	yp->tx_state = TX_HEAD;
600	ptt_on(dev);
601}
602
603static void yam_arbitrate(struct net_device *dev)
604{
605	struct yam_port *yp = netdev_priv(dev);
606
607	if (yp->magic != YAM_MAGIC || yp->tx_state != TX_OFF ||
608	    skb_queue_empty(&yp->send_queue))
609		return;
610	/* tx_state is TX_OFF and there is data to send */
611
612	if (yp->dupmode) {
613		/* Full duplex mode, don't wait */
614		yam_start_tx(dev, yp);
615		return;
616	}
617	if (yp->dcd) {
618		/* DCD on, wait slotime ... */
619		yp->slotcnt = yp->slot / 10;
620		return;
621	}
622	/* Is slottime passed ? */
623	if ((--yp->slotcnt) > 0)
624		return;
625
626	yp->slotcnt = yp->slot / 10;
627
628	/* is random > persist ? */
629	if (get_random_u8() > yp->pers)
630		return;
631
632	yam_start_tx(dev, yp);
633}
634
635static void yam_dotimer(struct timer_list *unused)
636{
637	int i;
638
639	for (i = 0; i < NR_PORTS; i++) {
640		struct net_device *dev = yam_devs[i];
641		if (dev && netif_running(dev))
642			yam_arbitrate(dev);
643	}
644	yam_timer.expires = jiffies + HZ / 100;
645	add_timer(&yam_timer);
646}
647
648static void yam_tx_byte(struct net_device *dev, struct yam_port *yp)
649{
650	struct sk_buff *skb;
651	unsigned char b, temp;
652
653	switch (yp->tx_state) {
654	case TX_OFF:
655		break;
656	case TX_HEAD:
657		if (--yp->tx_count <= 0) {
658			if (!(skb = skb_dequeue(&yp->send_queue))) {
659				ptt_off(dev);
660				yp->tx_state = TX_OFF;
661				break;
662			}
663			yp->tx_state = TX_DATA;
664			if (skb->data[0] != 0) {
665/*                              do_kiss_params(s, skb->data, skb->len); */
666				dev_kfree_skb_any(skb);
667				break;
668			}
669			yp->tx_len = skb->len - 1;	/* strip KISS byte */
670			if (yp->tx_len >= YAM_MAX_FRAME || yp->tx_len < 2) {
671				dev_kfree_skb_any(skb);
672				break;
673			}
674			skb_copy_from_linear_data_offset(skb, 1,
675							 yp->tx_buf,
676							 yp->tx_len);
677			dev_kfree_skb_any(skb);
678			yp->tx_count = 0;
679			yp->tx_crcl = 0x21;
680			yp->tx_crch = 0xf3;
681			yp->tx_state = TX_DATA;
682		}
683		break;
684	case TX_DATA:
685		b = yp->tx_buf[yp->tx_count++];
686		outb(b, THR(dev->base_addr));
687		temp = yp->tx_crcl;
688		yp->tx_crcl = chktabl[temp] ^ yp->tx_crch;
689		yp->tx_crch = chktabh[temp] ^ b;
690		if (yp->tx_count >= yp->tx_len) {
691			yp->tx_state = TX_CRC1;
692		}
693		break;
694	case TX_CRC1:
695		yp->tx_crch = chktabl[yp->tx_crcl] ^ yp->tx_crch;
696		yp->tx_crcl = chktabh[yp->tx_crcl] ^ chktabl[yp->tx_crch] ^ 0xff;
697		outb(yp->tx_crcl, THR(dev->base_addr));
698		yp->tx_state = TX_CRC2;
699		break;
700	case TX_CRC2:
701		outb(chktabh[yp->tx_crch] ^ 0xFF, THR(dev->base_addr));
702		if (skb_queue_empty(&yp->send_queue)) {
703			yp->tx_count = (yp->bitrate * yp->txtail) / 8000;
704			if (yp->dupmode == 2)
705				yp->tx_count += (yp->bitrate * yp->holdd) / 8;
706			if (yp->tx_count == 0)
707				yp->tx_count = 1;
708			yp->tx_state = TX_TAIL;
709		} else {
710			yp->tx_count = 1;
711			yp->tx_state = TX_HEAD;
712		}
713		++dev->stats.tx_packets;
714		break;
715	case TX_TAIL:
716		if (--yp->tx_count <= 0) {
717			yp->tx_state = TX_OFF;
718			ptt_off(dev);
719		}
720		break;
721	}
722}
723
724/***********************************************************************************
725* ISR routine
726************************************************************************************/
727
728static irqreturn_t yam_interrupt(int irq, void *dev_id)
729{
730	struct net_device *dev;
731	struct yam_port *yp;
732	unsigned char iir;
733	int counter = 100;
734	int i;
735	int handled = 0;
736
737	for (i = 0; i < NR_PORTS; i++) {
738		dev = yam_devs[i];
739		yp = netdev_priv(dev);
740
741		if (!netif_running(dev))
742			continue;
743
744		while ((iir = IIR_MASK & inb(IIR(dev->base_addr))) != IIR_NOPEND) {
745			unsigned char msr = inb(MSR(dev->base_addr));
746			unsigned char lsr = inb(LSR(dev->base_addr));
747			unsigned char rxb;
748
749			handled = 1;
750
751			if (lsr & LSR_OE)
752				++dev->stats.rx_fifo_errors;
753
754			yp->dcd = (msr & RX_DCD) ? 1 : 0;
755
756			if (--counter <= 0) {
757				printk(KERN_ERR "%s: too many irq iir=%d\n",
758						dev->name, iir);
759				goto out;
760			}
761			if (msr & TX_RDY) {
762				++yp->nb_mdint;
763				yam_tx_byte(dev, yp);
764			}
765			if (lsr & LSR_RXC) {
766				++yp->nb_rxint;
767				rxb = inb(RBR(dev->base_addr));
768				if (msr & RX_FLAG)
769					yam_rx_flag(dev, yp);
770				else
771					yam_rx_byte(dev, yp, rxb);
772			}
773		}
774	}
775out:
776	return IRQ_RETVAL(handled);
777}
778
779#ifdef CONFIG_PROC_FS
780
781static void *yam_seq_start(struct seq_file *seq, loff_t *pos)
782{
783	return (*pos < NR_PORTS) ? yam_devs[*pos] : NULL;
784}
785
786static void *yam_seq_next(struct seq_file *seq, void *v, loff_t *pos)
787{
788	++*pos;
789	return (*pos < NR_PORTS) ? yam_devs[*pos] : NULL;
790}
791
792static void yam_seq_stop(struct seq_file *seq, void *v)
793{
794}
795
796static int yam_seq_show(struct seq_file *seq, void *v)
797{
798	struct net_device *dev = v;
799	const struct yam_port *yp = netdev_priv(dev);
800
801	seq_printf(seq, "Device %s\n", dev->name);
802	seq_printf(seq, "  Up       %d\n", netif_running(dev));
803	seq_printf(seq, "  Speed    %u\n", yp->bitrate);
804	seq_printf(seq, "  IoBase   0x%x\n", yp->iobase);
805	seq_printf(seq, "  BaudRate %u\n", yp->baudrate);
806	seq_printf(seq, "  IRQ      %u\n", yp->irq);
807	seq_printf(seq, "  TxState  %u\n", yp->tx_state);
808	seq_printf(seq, "  Duplex   %u\n", yp->dupmode);
809	seq_printf(seq, "  HoldDly  %u\n", yp->holdd);
810	seq_printf(seq, "  TxDelay  %u\n", yp->txd);
811	seq_printf(seq, "  TxTail   %u\n", yp->txtail);
812	seq_printf(seq, "  SlotTime %u\n", yp->slot);
813	seq_printf(seq, "  Persist  %u\n", yp->pers);
814	seq_printf(seq, "  TxFrames %lu\n", dev->stats.tx_packets);
815	seq_printf(seq, "  RxFrames %lu\n", dev->stats.rx_packets);
816	seq_printf(seq, "  TxInt    %u\n", yp->nb_mdint);
817	seq_printf(seq, "  RxInt    %u\n", yp->nb_rxint);
818	seq_printf(seq, "  RxOver   %lu\n", dev->stats.rx_fifo_errors);
819	seq_printf(seq, "\n");
820	return 0;
821}
822
823static const struct seq_operations yam_seqops = {
824	.start = yam_seq_start,
825	.next = yam_seq_next,
826	.stop = yam_seq_stop,
827	.show = yam_seq_show,
828};
829#endif
830
831
832/* --------------------------------------------------------------------- */
833
834static int yam_open(struct net_device *dev)
835{
836	struct yam_port *yp = netdev_priv(dev);
837	enum uart u;
838	int i;
839	int ret=0;
840
841	printk(KERN_INFO "Trying %s at iobase 0x%lx irq %u\n", dev->name, dev->base_addr, dev->irq);
842
843	if (!yp->bitrate)
844		return -ENXIO;
845	if (!dev->base_addr || dev->base_addr > 0x1000 - YAM_EXTENT ||
846		dev->irq < 2 || dev->irq > 15) {
847		return -ENXIO;
848	}
849	if (!request_region(dev->base_addr, YAM_EXTENT, dev->name))
850	{
851		printk(KERN_ERR "%s: cannot 0x%lx busy\n", dev->name, dev->base_addr);
852		return -EACCES;
853	}
854	if ((u = yam_check_uart(dev->base_addr)) == c_uart_unknown) {
855		printk(KERN_ERR "%s: cannot find uart type\n", dev->name);
856		ret = -EIO;
857		goto out_release_base;
858	}
859	if (fpga_download(dev->base_addr, yp->bitrate)) {
860		printk(KERN_ERR "%s: cannot init FPGA\n", dev->name);
861		ret = -EIO;
862		goto out_release_base;
863	}
864	outb(0, IER(dev->base_addr));
865	if (request_irq(dev->irq, yam_interrupt, IRQF_SHARED, dev->name, dev)) {
866		printk(KERN_ERR "%s: irq %d busy\n", dev->name, dev->irq);
867		ret = -EBUSY;
868		goto out_release_base;
869	}
870
871	yam_set_uart(dev);
872
873	netif_start_queue(dev);
874
875	yp->slotcnt = yp->slot / 10;
876
877	/* Reset overruns for all ports - FPGA programming makes overruns */
878	for (i = 0; i < NR_PORTS; i++) {
879		struct net_device *yam_dev = yam_devs[i];
880
881		inb(LSR(yam_dev->base_addr));
882		yam_dev->stats.rx_fifo_errors = 0;
883	}
884
885	printk(KERN_INFO "%s at iobase 0x%lx irq %u uart %s\n", dev->name, dev->base_addr, dev->irq,
886		   uart_str[u]);
887	return 0;
888
889out_release_base:
890	release_region(dev->base_addr, YAM_EXTENT);
891	return ret;
892}
893
894/* --------------------------------------------------------------------- */
895
896static int yam_close(struct net_device *dev)
897{
898	struct sk_buff *skb;
899	struct yam_port *yp = netdev_priv(dev);
900
901	if (!dev)
902		return -EINVAL;
903
904	/*
905	 * disable interrupts
906	 */
907	outb(0, IER(dev->base_addr));
908	outb(1, MCR(dev->base_addr));
909	/* Remove IRQ handler if last */
910	free_irq(dev->irq,dev);
911	release_region(dev->base_addr, YAM_EXTENT);
912	netif_stop_queue(dev);
913	while ((skb = skb_dequeue(&yp->send_queue)))
914		dev_kfree_skb(skb);
915
916	printk(KERN_INFO "%s: close yam at iobase 0x%lx irq %u\n",
917		   yam_drvname, dev->base_addr, dev->irq);
918	return 0;
919}
920
921/* --------------------------------------------------------------------- */
922
923static int yam_siocdevprivate(struct net_device *dev, struct ifreq *ifr, void __user *data, int cmd)
924{
925	struct yam_port *yp = netdev_priv(dev);
926	struct yamdrv_ioctl_cfg yi;
927	struct yamdrv_ioctl_mcs *ym;
928	int ioctl_cmd;
929
930	if (copy_from_user(&ioctl_cmd, data, sizeof(int)))
931		return -EFAULT;
932
933	if (yp->magic != YAM_MAGIC)
934		return -EINVAL;
935
936	if (!capable(CAP_NET_ADMIN))
937		return -EPERM;
938
939	if (cmd != SIOCDEVPRIVATE)
940		return -EINVAL;
941
942	switch (ioctl_cmd) {
943
944	case SIOCYAMRESERVED:
945		return -EINVAL;			/* unused */
946
947	case SIOCYAMSMCS:
948		if (netif_running(dev))
949			return -EINVAL;		/* Cannot change this parameter when up */
950		ym = memdup_user(data, sizeof(struct yamdrv_ioctl_mcs));
951		if (IS_ERR(ym))
952			return PTR_ERR(ym);
953		if (ym->cmd != SIOCYAMSMCS || ym->bitrate > YAM_MAXBITRATE) {
954			kfree(ym);
955			return -EINVAL;
956		}
957		/* setting predef as 0 for loading userdefined mcs data */
958		add_mcs(ym->bits, ym->bitrate, 0);
959		kfree(ym);
960		break;
961
962	case SIOCYAMSCFG:
963		if (!capable(CAP_SYS_RAWIO))
964			return -EPERM;
965		if (copy_from_user(&yi, data, sizeof(struct yamdrv_ioctl_cfg)))
966			return -EFAULT;
967
968		if (yi.cmd != SIOCYAMSCFG)
969			return -EINVAL;
970		if ((yi.cfg.mask & YAM_IOBASE) && netif_running(dev))
971			return -EINVAL;		/* Cannot change this parameter when up */
972		if ((yi.cfg.mask & YAM_IRQ) && netif_running(dev))
973			return -EINVAL;		/* Cannot change this parameter when up */
974		if ((yi.cfg.mask & YAM_BITRATE) && netif_running(dev))
975			return -EINVAL;		/* Cannot change this parameter when up */
976		if ((yi.cfg.mask & YAM_BAUDRATE) && netif_running(dev))
977			return -EINVAL;		/* Cannot change this parameter when up */
978
979		if (yi.cfg.mask & YAM_IOBASE) {
980			yp->iobase = yi.cfg.iobase;
981			dev->base_addr = yi.cfg.iobase;
982		}
983		if (yi.cfg.mask & YAM_IRQ) {
984			if (yi.cfg.irq > 15)
985				return -EINVAL;
986			yp->irq = yi.cfg.irq;
987			dev->irq = yi.cfg.irq;
988		}
989		if (yi.cfg.mask & YAM_BITRATE) {
990			if (yi.cfg.bitrate > YAM_MAXBITRATE)
991				return -EINVAL;
992			yp->bitrate = yi.cfg.bitrate;
993		}
994		if (yi.cfg.mask & YAM_BAUDRATE) {
995			if (yi.cfg.baudrate > YAM_MAXBAUDRATE)
996				return -EINVAL;
997			yp->baudrate = yi.cfg.baudrate;
998		}
999		if (yi.cfg.mask & YAM_MODE) {
1000			if (yi.cfg.mode > YAM_MAXMODE)
1001				return -EINVAL;
1002			yp->dupmode = yi.cfg.mode;
1003		}
1004		if (yi.cfg.mask & YAM_HOLDDLY) {
1005			if (yi.cfg.holddly > YAM_MAXHOLDDLY)
1006				return -EINVAL;
1007			yp->holdd = yi.cfg.holddly;
1008		}
1009		if (yi.cfg.mask & YAM_TXDELAY) {
1010			if (yi.cfg.txdelay > YAM_MAXTXDELAY)
1011				return -EINVAL;
1012			yp->txd = yi.cfg.txdelay;
1013		}
1014		if (yi.cfg.mask & YAM_TXTAIL) {
1015			if (yi.cfg.txtail > YAM_MAXTXTAIL)
1016				return -EINVAL;
1017			yp->txtail = yi.cfg.txtail;
1018		}
1019		if (yi.cfg.mask & YAM_PERSIST) {
1020			if (yi.cfg.persist > YAM_MAXPERSIST)
1021				return -EINVAL;
1022			yp->pers = yi.cfg.persist;
1023		}
1024		if (yi.cfg.mask & YAM_SLOTTIME) {
1025			if (yi.cfg.slottime > YAM_MAXSLOTTIME)
1026				return -EINVAL;
1027			yp->slot = yi.cfg.slottime;
1028			yp->slotcnt = yp->slot / 10;
1029		}
1030		break;
1031
1032	case SIOCYAMGCFG:
1033		memset(&yi, 0, sizeof(yi));
1034		yi.cfg.mask = 0xffffffff;
1035		yi.cfg.iobase = yp->iobase;
1036		yi.cfg.irq = yp->irq;
1037		yi.cfg.bitrate = yp->bitrate;
1038		yi.cfg.baudrate = yp->baudrate;
1039		yi.cfg.mode = yp->dupmode;
1040		yi.cfg.txdelay = yp->txd;
1041		yi.cfg.holddly = yp->holdd;
1042		yi.cfg.txtail = yp->txtail;
1043		yi.cfg.persist = yp->pers;
1044		yi.cfg.slottime = yp->slot;
1045		if (copy_to_user(data, &yi, sizeof(struct yamdrv_ioctl_cfg)))
1046			return -EFAULT;
1047		break;
1048
1049	default:
1050		return -EINVAL;
1051
1052	}
1053
1054	return 0;
1055}
1056
1057/* --------------------------------------------------------------------- */
1058
1059static int yam_set_mac_address(struct net_device *dev, void *addr)
1060{
1061	struct sockaddr *sa = (struct sockaddr *) addr;
1062
1063	/* addr is an AX.25 shifted ASCII mac address */
1064	dev_addr_set(dev, sa->sa_data);
1065	return 0;
1066}
1067
1068/* --------------------------------------------------------------------- */
1069
1070static const struct net_device_ops yam_netdev_ops = {
1071	.ndo_open	     = yam_open,
1072	.ndo_stop	     = yam_close,
1073	.ndo_start_xmit      = yam_send_packet,
1074	.ndo_siocdevprivate  = yam_siocdevprivate,
1075	.ndo_set_mac_address = yam_set_mac_address,
1076};
1077
1078static void yam_setup(struct net_device *dev)
1079{
1080	struct yam_port *yp = netdev_priv(dev);
1081
1082	yp->magic = YAM_MAGIC;
1083	yp->bitrate = DEFAULT_BITRATE;
1084	yp->baudrate = DEFAULT_BITRATE * 2;
1085	yp->iobase = 0;
1086	yp->irq = 0;
1087	yp->dupmode = 0;
1088	yp->holdd = DEFAULT_HOLDD;
1089	yp->txd = DEFAULT_TXD;
1090	yp->txtail = DEFAULT_TXTAIL;
1091	yp->slot = DEFAULT_SLOT;
1092	yp->pers = DEFAULT_PERS;
1093	yp->dev = dev;
1094
1095	dev->base_addr = yp->iobase;
1096	dev->irq = yp->irq;
1097
1098	skb_queue_head_init(&yp->send_queue);
1099
1100	dev->netdev_ops = &yam_netdev_ops;
1101	dev->header_ops = &ax25_header_ops;
1102
1103	dev->type = ARPHRD_AX25;
1104	dev->hard_header_len = AX25_MAX_HEADER_LEN;
1105	dev->mtu = AX25_MTU;
1106	dev->addr_len = AX25_ADDR_LEN;
1107	memcpy(dev->broadcast, &ax25_bcast, AX25_ADDR_LEN);
1108	dev_addr_set(dev, (u8 *)&ax25_defaddr);
1109}
1110
1111static int __init yam_init_driver(void)
1112{
1113	struct net_device *dev;
1114	int i, err;
1115	char name[IFNAMSIZ];
1116
1117	printk(yam_drvinfo);
1118
1119	for (i = 0; i < NR_PORTS; i++) {
1120		sprintf(name, "yam%d", i);
1121
1122		dev = alloc_netdev(sizeof(struct yam_port), name,
1123				   NET_NAME_UNKNOWN, yam_setup);
1124		if (!dev) {
1125			pr_err("yam: cannot allocate net device\n");
1126			err = -ENOMEM;
1127			goto error;
1128		}
1129
1130		err = register_netdev(dev);
1131		if (err) {
1132			printk(KERN_WARNING "yam: cannot register net device %s\n", dev->name);
1133			free_netdev(dev);
1134			goto error;
1135		}
1136		yam_devs[i] = dev;
1137
1138	}
1139
1140	timer_setup(&yam_timer, yam_dotimer, 0);
1141	yam_timer.expires = jiffies + HZ / 100;
1142	add_timer(&yam_timer);
1143
1144	proc_create_seq("yam", 0444, init_net.proc_net, &yam_seqops);
1145	return 0;
1146 error:
1147	while (--i >= 0) {
1148		unregister_netdev(yam_devs[i]);
1149		free_netdev(yam_devs[i]);
1150	}
1151	return err;
1152}
1153
1154/* --------------------------------------------------------------------- */
1155
1156static void __exit yam_cleanup_driver(void)
1157{
1158	struct yam_mcs *p;
1159	int i;
1160
1161	del_timer_sync(&yam_timer);
1162	for (i = 0; i < NR_PORTS; i++) {
1163		struct net_device *dev = yam_devs[i];
1164		if (dev) {
1165			unregister_netdev(dev);
1166			free_netdev(dev);
1167		}
1168	}
1169
1170	while (yam_data) {
1171		p = yam_data;
1172		yam_data = yam_data->next;
1173		kfree(p);
1174	}
1175
1176	remove_proc_entry("yam", init_net.proc_net);
1177}
1178
1179/* --------------------------------------------------------------------- */
1180
1181MODULE_AUTHOR("Frederic Rible F1OAT frible@teaser.fr");
1182MODULE_DESCRIPTION("Yam amateur radio modem driver");
1183MODULE_LICENSE("GPL");
1184MODULE_FIRMWARE(FIRMWARE_1200);
1185MODULE_FIRMWARE(FIRMWARE_9600);
1186
1187module_init(yam_init_driver);
1188module_exit(yam_cleanup_driver);
1189
1190/* --------------------------------------------------------------------- */
1191
1192