1/* drivers/atm/idt77105.c - IDT77105 (PHY) driver */
2
3/* Written 1999 by Greg Banks, NEC Australia <gnb@linuxfan.com>. Based on suni.c */
4
5
6#include <linux/module.h>
7#include <linux/sched.h>
8#include <linux/kernel.h>
9#include <linux/mm.h>
10#include <linux/errno.h>
11#include <linux/atmdev.h>
12#include <linux/sonet.h>
13#include <linux/delay.h>
14#include <linux/timer.h>
15#include <linux/init.h>
16#include <linux/capability.h>
17#include <linux/atm_idt77105.h>
18#include <asm/system.h>
19#include <asm/param.h>
20#include <asm/uaccess.h>
21
22#include "idt77105.h"
23
24#undef GENERAL_DEBUG
25
26#ifdef GENERAL_DEBUG
27#define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
28#else
29#define DPRINTK(format,args...)
30#endif
31
32
33struct idt77105_priv {
34	struct idt77105_stats stats;    /* link diagnostics */
35	struct atm_dev *dev;		/* device back-pointer */
36	struct idt77105_priv *next;
37        int loop_mode;
38        unsigned char old_mcr;          /* storage of MCR reg while signal lost */
39};
40
41
42#define PRIV(dev) ((struct idt77105_priv *) dev->phy_data)
43
44#define PUT(val,reg) dev->ops->phy_put(dev,val,IDT77105_##reg)
45#define GET(reg) dev->ops->phy_get(dev,IDT77105_##reg)
46
47static void idt77105_stats_timer_func(unsigned long);
48static void idt77105_restart_timer_func(unsigned long);
49
50
51static struct timer_list stats_timer = {
52    function:	&idt77105_stats_timer_func
53};
54static struct timer_list restart_timer = {
55    function:	&idt77105_restart_timer_func
56};
57static int start_timer = 1;
58static struct idt77105_priv *idt77105_all = NULL;
59
60/*
61 * Retrieve the value of one of the IDT77105's counters.
62 * `counter' is one of the IDT77105_CTRSEL_* constants.
63 */
64static u16 get_counter(struct atm_dev *dev, int counter)
65{
66        u16 val;
67
68        /* write the counter bit into PHY register 6 */
69        PUT(counter, CTRSEL);
70        /* read the low 8 bits from register 4 */
71        val = GET(CTRLO);
72        /* read the high 8 bits from register 5 */
73        val |= GET(CTRHI)<<8;
74
75        return val;
76}
77
78/*
79 * Timer function called every second to gather statistics
80 * from the 77105. This is done because the h/w registers
81 * will overflow if not read at least once per second. The
82 * kernel's stats are much higher precision. Also, having
83 * a separate copy of the stats allows implementation of
84 * an ioctl which gathers the stats *without* zero'ing them.
85 */
86static void idt77105_stats_timer_func(unsigned long dummy)
87{
88	struct idt77105_priv *walk;
89	struct atm_dev *dev;
90	struct idt77105_stats *stats;
91
92        DPRINTK("IDT77105 gathering statistics\n");
93	for (walk = idt77105_all; walk; walk = walk->next) {
94		dev = walk->dev;
95
96		stats = &walk->stats;
97                stats->symbol_errors += get_counter(dev, IDT77105_CTRSEL_SEC);
98                stats->tx_cells += get_counter(dev, IDT77105_CTRSEL_TCC);
99                stats->rx_cells += get_counter(dev, IDT77105_CTRSEL_RCC);
100                stats->rx_hec_errors += get_counter(dev, IDT77105_CTRSEL_RHEC);
101	}
102        if (!start_timer) mod_timer(&stats_timer,jiffies+IDT77105_STATS_TIMER_PERIOD);
103}
104
105
106/*
107 * A separate timer func which handles restarting PHY chips which
108 * have had the cable re-inserted after being pulled out. This is
109 * done by polling the Good Signal Bit in the Interrupt Status
110 * register every 5 seconds. The other technique (checking Good
111 * Signal Bit in the interrupt handler) cannot be used because PHY
112 * interrupts need to be disabled when the cable is pulled out
113 * to avoid lots of spurious cell error interrupts.
114 */
115static void idt77105_restart_timer_func(unsigned long dummy)
116{
117	struct idt77105_priv *walk;
118	struct atm_dev *dev;
119        unsigned char istat;
120
121        DPRINTK("IDT77105 checking for cable re-insertion\n");
122	for (walk = idt77105_all; walk; walk = walk->next) {
123		dev = walk->dev;
124
125                if (dev->signal != ATM_PHY_SIG_LOST)
126                    continue;
127
128                istat = GET(ISTAT); /* side effect: clears all interrupt status bits */
129                if (istat & IDT77105_ISTAT_GOODSIG) {
130                    /* Found signal again */
131                    dev->signal = ATM_PHY_SIG_FOUND;
132	            printk(KERN_NOTICE "%s(itf %d): signal detected again\n",
133                        dev->type,dev->number);
134                    /* flush the receive FIFO */
135                    PUT( GET(DIAG) | IDT77105_DIAG_RFLUSH, DIAG);
136                    /* re-enable interrupts */
137	            PUT( walk->old_mcr ,MCR);
138                }
139	}
140        if (!start_timer) mod_timer(&restart_timer,jiffies+IDT77105_RESTART_TIMER_PERIOD);
141}
142
143
144static int fetch_stats(struct atm_dev *dev,struct idt77105_stats *arg,int zero)
145{
146	unsigned long flags;
147	struct idt77105_stats stats;
148
149	save_flags(flags);
150	cli();
151	memcpy(&stats, &PRIV(dev)->stats, sizeof(struct idt77105_stats));
152	if (zero)
153		memset(&PRIV(dev)->stats, 0, sizeof(struct idt77105_stats));
154	restore_flags(flags);
155	if (arg == NULL)
156		return 0;
157	return copy_to_user(arg, &PRIV(dev)->stats,
158		    sizeof(struct idt77105_stats)) ? -EFAULT : 0;
159}
160
161
162static int set_loopback(struct atm_dev *dev,int mode)
163{
164	int diag;
165
166	diag = GET(DIAG) & ~IDT77105_DIAG_LCMASK;
167	switch (mode) {
168		case ATM_LM_NONE:
169			break;
170		case ATM_LM_LOC_ATM:
171			diag |= IDT77105_DIAG_LC_PHY_LOOPBACK;
172			break;
173		case ATM_LM_RMT_ATM:
174			diag |= IDT77105_DIAG_LC_LINE_LOOPBACK;
175			break;
176		default:
177			return -EINVAL;
178	}
179	PUT(diag,DIAG);
180	printk(KERN_NOTICE "%s(%d) Loopback mode is: %s\n", dev->type,
181	    dev->number,
182	    (mode == ATM_LM_NONE ? "NONE" :
183	      (mode == ATM_LM_LOC_ATM ? "DIAG (local)" :
184		(mode == IDT77105_DIAG_LC_LINE_LOOPBACK ? "LOOP (remote)" :
185		  "unknown")))
186		    );
187	PRIV(dev)->loop_mode = mode;
188	return 0;
189}
190
191
192static int idt77105_ioctl(struct atm_dev *dev,unsigned int cmd,void *arg)
193{
194        printk(KERN_NOTICE "%s(%d) idt77105_ioctl() called\n",dev->type,dev->number);
195	switch (cmd) {
196		case IDT77105_GETSTATZ:
197			if (!capable(CAP_NET_ADMIN)) return -EPERM;
198			/* fall through */
199		case IDT77105_GETSTAT:
200			return fetch_stats(dev,(struct idt77105_stats *) arg,
201			    cmd == IDT77105_GETSTATZ);
202		case ATM_SETLOOP:
203			return set_loopback(dev,(int) (long) arg);
204		case ATM_GETLOOP:
205			return put_user(PRIV(dev)->loop_mode,(int *) arg) ?
206			    -EFAULT : 0;
207		case ATM_QUERYLOOP:
208			return put_user(ATM_LM_LOC_ATM | ATM_LM_RMT_ATM,
209			    (int *) arg) ? -EFAULT : 0;
210		default:
211			return -ENOIOCTLCMD;
212	}
213}
214
215
216
217static void idt77105_int(struct atm_dev *dev)
218{
219        unsigned char istat;
220
221        istat = GET(ISTAT); /* side effect: clears all interrupt status bits */
222
223        DPRINTK("IDT77105 generated an interrupt, istat=%02x\n", (unsigned)istat);
224
225        if (istat & IDT77105_ISTAT_RSCC) {
226            /* Rx Signal Condition Change - line went up or down */
227            if (istat & IDT77105_ISTAT_GOODSIG) {   /* signal detected again */
228                /* This should not happen (restart timer does it) but JIC */
229                dev->signal = ATM_PHY_SIG_FOUND;
230            } else {    /* signal lost */
231                /*
232                 * Disable interrupts and stop all transmission and
233                 * reception - the restart timer will restore these.
234                 */
235                PRIV(dev)->old_mcr = GET(MCR);
236	        PUT(
237                    (PRIV(dev)->old_mcr|
238                    IDT77105_MCR_DREC|
239                    IDT77105_MCR_DRIC|
240                    IDT77105_MCR_HALTTX
241                    ) & ~IDT77105_MCR_EIP, MCR);
242                dev->signal = ATM_PHY_SIG_LOST;
243	        printk(KERN_NOTICE "%s(itf %d): signal lost\n",
244                    dev->type,dev->number);
245            }
246        }
247
248        if (istat & IDT77105_ISTAT_RFO) {
249            /* Rx FIFO Overrun -- perform a FIFO flush */
250            PUT( GET(DIAG) | IDT77105_DIAG_RFLUSH, DIAG);
251	    printk(KERN_NOTICE "%s(itf %d): receive FIFO overrun\n",
252                dev->type,dev->number);
253        }
254#ifdef GENERAL_DEBUG
255        if (istat & (IDT77105_ISTAT_HECERR | IDT77105_ISTAT_SCR |
256                     IDT77105_ISTAT_RSE)) {
257            /* normally don't care - just report in stats */
258	    printk(KERN_NOTICE "%s(itf %d): received cell with error\n",
259                dev->type,dev->number);
260        }
261#endif
262}
263
264
265static int idt77105_start(struct atm_dev *dev)
266{
267	unsigned long flags;
268
269	if (!(PRIV(dev) = kmalloc(sizeof(struct idt77105_priv),GFP_KERNEL)))
270		return -ENOMEM;
271	PRIV(dev)->dev = dev;
272	save_flags(flags);
273	cli();
274	PRIV(dev)->next = idt77105_all;
275	idt77105_all = PRIV(dev);
276	restore_flags(flags);
277	memset(&PRIV(dev)->stats,0,sizeof(struct idt77105_stats));
278
279        /* initialise dev->signal from Good Signal Bit */
280        dev->signal = GET(ISTAT) & IDT77105_ISTAT_GOODSIG ? ATM_PHY_SIG_FOUND :
281	  ATM_PHY_SIG_LOST;
282	if (dev->signal == ATM_PHY_SIG_LOST)
283		printk(KERN_WARNING "%s(itf %d): no signal\n",dev->type,
284		    dev->number);
285
286        /* initialise loop mode from hardware */
287        switch ( GET(DIAG) & IDT77105_DIAG_LCMASK ) {
288        case IDT77105_DIAG_LC_NORMAL:
289            PRIV(dev)->loop_mode = ATM_LM_NONE;
290            break;
291        case IDT77105_DIAG_LC_PHY_LOOPBACK:
292            PRIV(dev)->loop_mode = ATM_LM_LOC_ATM;
293            break;
294        case IDT77105_DIAG_LC_LINE_LOOPBACK:
295            PRIV(dev)->loop_mode = ATM_LM_RMT_ATM;
296            break;
297        }
298
299        /* enable interrupts, e.g. on loss of signal */
300        PRIV(dev)->old_mcr = GET(MCR);
301        if (dev->signal == ATM_PHY_SIG_FOUND) {
302            PRIV(dev)->old_mcr |= IDT77105_MCR_EIP;
303	    PUT(PRIV(dev)->old_mcr, MCR);
304        }
305
306
307	idt77105_stats_timer_func(0); /* clear 77105 counters */
308	(void) fetch_stats(dev,NULL,1); /* clear kernel counters */
309
310	cli();
311	if (!start_timer) restore_flags(flags);
312	else {
313		start_timer = 0;
314		restore_flags(flags);
315
316		init_timer(&stats_timer);
317		stats_timer.expires = jiffies+IDT77105_STATS_TIMER_PERIOD;
318		stats_timer.function = idt77105_stats_timer_func;
319		add_timer(&stats_timer);
320
321		init_timer(&restart_timer);
322		restart_timer.expires = jiffies+IDT77105_RESTART_TIMER_PERIOD;
323		restart_timer.function = idt77105_restart_timer_func;
324		add_timer(&restart_timer);
325	}
326	return 0;
327}
328
329
330static const struct atmphy_ops idt77105_ops = {
331	idt77105_start,
332	idt77105_ioctl,
333	idt77105_int
334};
335
336
337int __init idt77105_init(struct atm_dev *dev)
338{
339	MOD_INC_USE_COUNT;
340
341	dev->phy = &idt77105_ops;
342	return 0;
343}
344
345
346/*
347 * TODO: this function should be called through phy_ops
348 * but that will not be possible for some time as there is
349 * currently a freeze on modifying that structure
350 * -- Greg Banks, 13 Sep 1999
351 */
352int idt77105_stop(struct atm_dev *dev)
353{
354	struct idt77105_priv *walk, *prev;
355
356        DPRINTK("%s(itf %d): stopping IDT77105\n",dev->type,dev->number);
357
358        /* disable interrupts */
359	PUT( GET(MCR) & ~IDT77105_MCR_EIP, MCR );
360
361        /* detach private struct from atm_dev & free */
362	for (prev = NULL, walk = idt77105_all ;
363             walk != NULL;
364             prev = walk, walk = walk->next) {
365            if (walk->dev == dev) {
366                if (prev != NULL)
367                    prev->next = walk->next;
368                else
369                    idt77105_all = walk->next;
370	        dev->phy = NULL;
371                PRIV(dev) = NULL;
372                kfree(walk);
373                break;
374            }
375        }
376
377	MOD_DEC_USE_COUNT;
378	return 0;
379}
380
381
382
383EXPORT_SYMBOL(idt77105_init);
384EXPORT_SYMBOL(idt77105_stop);
385
386MODULE_LICENSE("GPL");
387
388#ifdef MODULE
389
390int init_module(void)
391{
392	return 0;
393}
394
395
396void cleanup_module(void)
397{
398        /* turn off timers */
399        del_timer(&stats_timer);
400        del_timer(&restart_timer);
401}
402
403#endif
404