drivers/atm/idt77105.c

   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 <linux/spinlock.h>
  19 #include <asm/system.h>
  20 #include <asm/param.h>
  21 #include <asm/uaccess.h>
  22
  23 #include "idt77105.h"
  24
  25 #undef GENERAL_DEBUG
  26
  27 #ifdef GENERAL_DEBUG
  28 #define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
  29 #else
  30 #define DPRINTK(format,args...)
  31 #endif
  32
  33
  34 struct idt77105_priv {
  35         struct idt77105_stats stats;    /* link diagnostics */
  36         struct atm_dev *dev;            /* device back-pointer */
  37         struct idt77105_priv *next;
  38         int loop_mode;
  39         unsigned char old_mcr;          /* storage of MCR reg while signal lost */
  40 };
  41
  42 static DEFINE_SPINLOCK(idt77105_priv_lock);
  43
  44 #define PRIV(dev) ((struct idt77105_priv *) dev->phy_data)
  45
  46 #define PUT(val,reg) dev->ops->phy_put(dev,val,IDT77105_##reg)
  47 #define GET(reg) dev->ops->phy_get(dev,IDT77105_##reg)
  48
  49 static void idt77105_stats_timer_func(unsigned long);
  50 static void idt77105_restart_timer_func(unsigned long);
  51
  52
  53 static DEFINE_TIMER(stats_timer, idt77105_stats_timer_func, 0, 0);
  54 static DEFINE_TIMER(restart_timer, idt77105_restart_timer_func, 0, 0);
  55 static int start_timer = 1;
  56 static struct idt77105_priv *idt77105_all = NULL;
  57
  58 /*
  59  * Retrieve the value of one of the IDT77105's counters.
  60  * `counter' is one of the IDT77105_CTRSEL_* constants.
  61  */
  62 static u16 get_counter(struct atm_dev *dev, int counter)
  63 {
  64         u16 val;
  65
  66         /* write the counter bit into PHY register 6 */
  67         PUT(counter, CTRSEL);
  68         /* read the low 8 bits from register 4 */
  69         val = GET(CTRLO);
  70         /* read the high 8 bits from register 5 */
  71         val |= GET(CTRHI)<<8;
  72
  73         return val;
  74 }
  75
  76 /*
  77  * Timer function called every second to gather statistics
  78  * from the 77105. This is done because the h/w registers
  79  * will overflow if not read at least once per second. The
  80  * kernel's stats are much higher precision. Also, having
  81  * a separate copy of the stats allows implementation of
  82  * an ioctl which gathers the stats *without* zero'ing them.
  83  */
  84 static void idt77105_stats_timer_func(unsigned long dummy)
  85 {
  86         struct idt77105_priv *walk;
  87         struct atm_dev *dev;
  88         struct idt77105_stats *stats;
  89
  90         DPRINTK("IDT77105 gathering statistics\n");
  91         for (walk = idt77105_all; walk; walk = walk->next) {
  92                 dev = walk->dev;
  93
  94                 stats = &walk->stats;
  95                 stats->symbol_errors += get_counter(dev, IDT77105_CTRSEL_SEC);
  96                 stats->tx_cells += get_counter(dev, IDT77105_CTRSEL_TCC);
  97                 stats->rx_cells += get_counter(dev, IDT77105_CTRSEL_RCC);
  98                 stats->rx_hec_errors += get_counter(dev, IDT77105_CTRSEL_RHEC);
  99         }
 100         if (!start_timer) mod_timer(&stats_timer,jiffies+IDT77105_STATS_TIMER_PERIOD);
 101 }
 102
 103
 104 /*
 105  * A separate timer func which handles restarting PHY chips which
 106  * have had the cable re-inserted after being pulled out. This is
 107  * done by polling the Good Signal Bit in the Interrupt Status
 108  * register every 5 seconds. The other technique (checking Good
 109  * Signal Bit in the interrupt handler) cannot be used because PHY
 110  * interrupts need to be disabled when the cable is pulled out
 111  * to avoid lots of spurious cell error interrupts.
 112  */
 113 static void idt77105_restart_timer_func(unsigned long dummy)
 114 {
 115         struct idt77105_priv *walk;
 116         struct atm_dev *dev;
 117         unsigned char istat;
 118
 119         DPRINTK("IDT77105 checking for cable re-insertion\n");
 120         for (walk = idt77105_all; walk; walk = walk->next) {
 121                 dev = walk->dev;
 122
 123                 if (dev->signal != ATM_PHY_SIG_LOST)
 124                     continue;
 125
 126                 istat = GET(ISTAT); /* side effect: clears all interrupt status bits */
 127                 if (istat & IDT77105_ISTAT_GOODSIG) {
 128                     /* Found signal again */
 129                     dev->signal = ATM_PHY_SIG_FOUND;
 130                     printk(KERN_NOTICE "%s(itf %d): signal detected again\n",
 131                         dev->type,dev->number);
 132                     /* flush the receive FIFO */
 133                     PUT( GET(DIAG) | IDT77105_DIAG_RFLUSH, DIAG);
 134                     /* re-enable interrupts */
 135                     PUT( walk->old_mcr ,MCR);
 136                 }
 137         }
 138         if (!start_timer) mod_timer(&restart_timer,jiffies+IDT77105_RESTART_TIMER_PERIOD);
 139 }
 140
 141
 142 static int fetch_stats(struct atm_dev *dev,struct idt77105_stats __user *arg,int zero)
 143 {
 144         unsigned long flags;
 145         struct idt77105_stats stats;
 146
 147         spin_lock_irqsave(&idt77105_priv_lock, flags);
 148         memcpy(&stats, &PRIV(dev)->stats, sizeof(struct idt77105_stats));
 149         if (zero)
 150                 memset(&PRIV(dev)->stats, 0, sizeof(struct idt77105_stats));
 151         spin_unlock_irqrestore(&idt77105_priv_lock, flags);
 152         if (arg == NULL)
 153                 return 0;
 154         return copy_to_user(arg, &PRIV(dev)->stats,
 155                     sizeof(struct idt77105_stats)) ? -EFAULT : 0;
 156 }
 157
 158
 159 static int set_loopback(struct atm_dev *dev,int mode)
 160 {
 161         int diag;
 162
 163         diag = GET(DIAG) & ~IDT77105_DIAG_LCMASK;
 164         switch (mode) {
 165                 case ATM_LM_NONE:
 166                         break;
 167                 case ATM_LM_LOC_ATM:
 168                         diag |= IDT77105_DIAG_LC_PHY_LOOPBACK;
 169                         break;
 170                 case ATM_LM_RMT_ATM:
 171                         diag |= IDT77105_DIAG_LC_LINE_LOOPBACK;
 172                         break;
 173                 default:
 174                         return -EINVAL;
 175         }
 176         PUT(diag,DIAG);
 177         printk(KERN_NOTICE "%s(%d) Loopback mode is: %s\n", dev->type,
 178             dev->number,
 179             (mode == ATM_LM_NONE ? "NONE" :
 180               (mode == ATM_LM_LOC_ATM ? "DIAG (local)" :
 181                 (mode == IDT77105_DIAG_LC_LINE_LOOPBACK ? "LOOP (remote)" :
 182                   "unknown")))
 183                     );
 184         PRIV(dev)->loop_mode = mode;
 185         return 0;
 186 }
 187
 188
 189 static int idt77105_ioctl(struct atm_dev *dev,unsigned int cmd,void __user *arg)
 190 {
 191         printk(KERN_NOTICE "%s(%d) idt77105_ioctl() called\n",dev->type,dev->number);
 192         switch (cmd) {
 193                 case IDT77105_GETSTATZ:
 194                         if (!capable(CAP_NET_ADMIN)) return -EPERM;
 195                         /* fall through */
 196                 case IDT77105_GETSTAT:
 197                         return fetch_stats(dev, arg, cmd == IDT77105_GETSTATZ);
 198                 case ATM_SETLOOP:
 199                         return set_loopback(dev,(int)(unsigned long) arg);
 200                 case ATM_GETLOOP:
 201                         return put_user(PRIV(dev)->loop_mode,(int __user *)arg) ?
 202                             -EFAULT : 0;
 203                 case ATM_QUERYLOOP:
 204                         return put_user(ATM_LM_LOC_ATM | ATM_LM_RMT_ATM,
 205                             (int __user *) arg) ? -EFAULT : 0;
 206                 default:
 207                         return -ENOIOCTLCMD;
 208         }
 209 }
 210
 211
 212
 213 static void idt77105_int(struct atm_dev *dev)
 214 {
 215         unsigned char istat;
 216
 217         istat = GET(ISTAT); /* side effect: clears all interrupt status bits */
 218
 219         DPRINTK("IDT77105 generated an interrupt, istat=%02x\n", (unsigned)istat);
 220
 221         if (istat & IDT77105_ISTAT_RSCC) {
 222             /* Rx Signal Condition Change - line went up or down */
 223             if (istat & IDT77105_ISTAT_GOODSIG) {   /* signal detected again */
 224                 /* This should not happen (restart timer does it) but JIC */
 225                 dev->signal = ATM_PHY_SIG_FOUND;
 226             } else {    /* signal lost */
 227                 /*
 228                  * Disable interrupts and stop all transmission and
 229                  * reception - the restart timer will restore these.
 230                  */
 231                 PRIV(dev)->old_mcr = GET(MCR);
 232                 PUT(
 233                     (PRIV(dev)->old_mcr|
 234                     IDT77105_MCR_DREC|
 235                     IDT77105_MCR_DRIC|
 236                     IDT77105_MCR_HALTTX
 237                     ) & ~IDT77105_MCR_EIP, MCR);
 238                 dev->signal = ATM_PHY_SIG_LOST;
 239                 printk(KERN_NOTICE "%s(itf %d): signal lost\n",
 240                     dev->type,dev->number);
 241             }
 242         }
 243
 244         if (istat & IDT77105_ISTAT_RFO) {
 245             /* Rx FIFO Overrun -- perform a FIFO flush */
 246             PUT( GET(DIAG) | IDT77105_DIAG_RFLUSH, DIAG);
 247             printk(KERN_NOTICE "%s(itf %d): receive FIFO overrun\n",
 248                 dev->type,dev->number);
 249         }
 250 #ifdef GENERAL_DEBUG
 251         if (istat & (IDT77105_ISTAT_HECERR | IDT77105_ISTAT_SCR |
 252                      IDT77105_ISTAT_RSE)) {
 253             /* normally don't care - just report in stats */
 254             printk(KERN_NOTICE "%s(itf %d): received cell with error\n",
 255                 dev->type,dev->number);
 256         }
 257 #endif
 258 }
 259
 260
 261 static int idt77105_start(struct atm_dev *dev)
 262 {
 263         unsigned long flags;
 264
 265         if (!(dev->dev_data = kmalloc(sizeof(struct idt77105_priv),GFP_KERNEL)))
 266                 return -ENOMEM;
 267         PRIV(dev)->dev = dev;
 268         spin_lock_irqsave(&idt77105_priv_lock, flags);
 269         PRIV(dev)->next = idt77105_all;
 270         idt77105_all = PRIV(dev);
 271         spin_unlock_irqrestore(&idt77105_priv_lock, flags);
 272         memset(&PRIV(dev)->stats,0,sizeof(struct idt77105_stats));
 273
 274         /* initialise dev->signal from Good Signal Bit */
 275         dev->signal = GET(ISTAT) & IDT77105_ISTAT_GOODSIG ? ATM_PHY_SIG_FOUND :
 276           ATM_PHY_SIG_LOST;
 277         if (dev->signal == ATM_PHY_SIG_LOST)
 278                 printk(KERN_WARNING "%s(itf %d): no signal\n",dev->type,
 279                     dev->number);
 280
 281         /* initialise loop mode from hardware */
 282         switch ( GET(DIAG) & IDT77105_DIAG_LCMASK ) {
 283         case IDT77105_DIAG_LC_NORMAL:
 284             PRIV(dev)->loop_mode = ATM_LM_NONE;
 285             break;
 286         case IDT77105_DIAG_LC_PHY_LOOPBACK:
 287             PRIV(dev)->loop_mode = ATM_LM_LOC_ATM;
 288             break;
 289         case IDT77105_DIAG_LC_LINE_LOOPBACK:
 290             PRIV(dev)->loop_mode = ATM_LM_RMT_ATM;
 291             break;
 292         }
 293
 294         /* enable interrupts, e.g. on loss of signal */
 295         PRIV(dev)->old_mcr = GET(MCR);
 296         if (dev->signal == ATM_PHY_SIG_FOUND) {
 297             PRIV(dev)->old_mcr |= IDT77105_MCR_EIP;
 298             PUT(PRIV(dev)->old_mcr, MCR);
 299         }
 300
 301
 302         idt77105_stats_timer_func(0); /* clear 77105 counters */
 303         (void) fetch_stats(dev,NULL,1); /* clear kernel counters */
 304
 305         spin_lock_irqsave(&idt77105_priv_lock, flags);
 306         if (start_timer) {
 307                 start_timer = 0;
 308
 309                 init_timer(&stats_timer);
 310                 stats_timer.expires = jiffies+IDT77105_STATS_TIMER_PERIOD;
 311                 stats_timer.function = idt77105_stats_timer_func;
 312                 add_timer(&stats_timer);
 313
 314                 init_timer(&restart_timer);
 315                 restart_timer.expires = jiffies+IDT77105_RESTART_TIMER_PERIOD;
 316                 restart_timer.function = idt77105_restart_timer_func;
 317                 add_timer(&restart_timer);
 318         }
 319         spin_unlock_irqrestore(&idt77105_priv_lock, flags);
 320         return 0;
 321 }
 322
 323
 324 static int idt77105_stop(struct atm_dev *dev)
 325 {
 326         struct idt77105_priv *walk, *prev;
 327
 328         DPRINTK("%s(itf %d): stopping IDT77105\n",dev->type,dev->number);
 329
 330         /* disable interrupts */
 331         PUT( GET(MCR) & ~IDT77105_MCR_EIP, MCR );
 332
 333         /* detach private struct from atm_dev & free */
 334         for (prev = NULL, walk = idt77105_all ;
 335              walk != NULL;
 336              prev = walk, walk = walk->next) {
 337             if (walk->dev == dev) {
 338                 if (prev != NULL)
 339                     prev->next = walk->next;
 340                 else
 341                     idt77105_all = walk->next;
 342                 dev->phy = NULL;
 343                 dev->dev_data = NULL;
 344                 kfree(walk);
 345                 break;
 346             }
 347         }
 348
 349         return 0;
 350 }
 351
 352
 353 static const struct atmphy_ops idt77105_ops = {
 354         .start =        idt77105_start,
 355         .ioctl =        idt77105_ioctl,
 356         .interrupt =    idt77105_int,
 357         .stop =         idt77105_stop,
 358 };
 359
 360
 361 int __devinit idt77105_init(struct atm_dev *dev)
 362 {
 363         dev->phy = &idt77105_ops;
 364         return 0;
 365 }
 366
 367 EXPORT_SYMBOL(idt77105_init);
 368
 369 static void __exit idt77105_exit(void)
 370 {
 371         /* turn off timers */
 372         del_timer(&stats_timer);
 373         del_timer(&restart_timer);
 374 }
 375
 376 module_exit(idt77105_exit);
 377
 378 MODULE_LICENSE("GPL");