Version:  2.0.40 2.2.26 2.4.37 2.6.39 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15

Linux/drivers/pcmcia/i82092.c

  1 /* 
  2  * Driver for Intel I82092AA PCI-PCMCIA bridge.
  3  *
  4  * (C) 2001 Red Hat, Inc.
  5  *
  6  * Author: Arjan Van De Ven <arjanv@redhat.com>
  7  * Loosly based on i82365.c from the pcmcia-cs package
  8  */
  9 
 10 #include <linux/kernel.h>
 11 #include <linux/module.h>
 12 #include <linux/pci.h>
 13 #include <linux/init.h>
 14 #include <linux/workqueue.h>
 15 #include <linux/interrupt.h>
 16 #include <linux/device.h>
 17 
 18 #include <pcmcia/ss.h>
 19 
 20 #include <asm/io.h>
 21 
 22 #include "i82092aa.h"
 23 #include "i82365.h"
 24 
 25 MODULE_LICENSE("GPL");
 26 
 27 /* PCI core routines */
 28 static DEFINE_PCI_DEVICE_TABLE(i82092aa_pci_ids) = {
 29         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82092AA_0) },
 30         { }
 31 };
 32 MODULE_DEVICE_TABLE(pci, i82092aa_pci_ids);
 33 
 34 static struct pci_driver i82092aa_pci_driver = {
 35         .name           = "i82092aa",
 36         .id_table       = i82092aa_pci_ids,
 37         .probe          = i82092aa_pci_probe,
 38         .remove         = i82092aa_pci_remove,
 39 };
 40 
 41 
 42 /* the pccard structure and its functions */
 43 static struct pccard_operations i82092aa_operations = {
 44         .init                   = i82092aa_init,
 45         .get_status             = i82092aa_get_status,
 46         .set_socket             = i82092aa_set_socket,
 47         .set_io_map             = i82092aa_set_io_map,
 48         .set_mem_map            = i82092aa_set_mem_map,
 49 };
 50 
 51 /* The card can do up to 4 sockets, allocate a structure for each of them */
 52 
 53 struct socket_info {
 54         int     number;
 55         int     card_state;     /*  0 = no socket,
 56                                     1 = empty socket, 
 57                                     2 = card but not initialized,
 58                                     3 = operational card */
 59         unsigned int io_base;   /* base io address of the socket */
 60         
 61         struct pcmcia_socket socket;
 62         struct pci_dev *dev;    /* The PCI device for the socket */
 63 };
 64 
 65 #define MAX_SOCKETS 4
 66 static struct socket_info sockets[MAX_SOCKETS];
 67 static int socket_count;  /* shortcut */                                                                                
 68 
 69 
 70 static int i82092aa_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
 71 {
 72         unsigned char configbyte;
 73         int i, ret;
 74         
 75         enter("i82092aa_pci_probe");
 76         
 77         if ((ret = pci_enable_device(dev)))
 78                 return ret;
 79                 
 80         pci_read_config_byte(dev, 0x40, &configbyte);  /* PCI Configuration Control */
 81         switch(configbyte&6) {
 82                 case 0:
 83                         socket_count = 2;
 84                         break;
 85                 case 2:
 86                         socket_count = 1;
 87                         break;
 88                 case 4:
 89                 case 6:
 90                         socket_count = 4;
 91                         break;
 92                         
 93                 default:
 94                         printk(KERN_ERR "i82092aa: Oops, you did something we didn't think of.\n");
 95                         ret = -EIO;
 96                         goto err_out_disable;
 97         }
 98         printk(KERN_INFO "i82092aa: configured as a %d socket device.\n", socket_count);
 99 
100         if (!request_region(pci_resource_start(dev, 0), 2, "i82092aa")) {
101                 ret = -EBUSY;
102                 goto err_out_disable;
103         }
104         
105         for (i = 0;i<socket_count;i++) {
106                 sockets[i].card_state = 1; /* 1 = present but empty */
107                 sockets[i].io_base = pci_resource_start(dev, 0);
108                 sockets[i].socket.features |= SS_CAP_PCCARD;
109                 sockets[i].socket.map_size = 0x1000;
110                 sockets[i].socket.irq_mask = 0;
111                 sockets[i].socket.pci_irq  = dev->irq;
112                 sockets[i].socket.cb_dev  = dev;
113                 sockets[i].socket.owner = THIS_MODULE;
114 
115                 sockets[i].number = i;
116                 
117                 if (card_present(i)) {
118                         sockets[i].card_state = 3;
119                         dprintk(KERN_DEBUG "i82092aa: slot %i is occupied\n",i);
120                 } else {
121                         dprintk(KERN_DEBUG "i82092aa: slot %i is vacant\n",i);
122                 }
123         }
124                 
125         /* Now, specifiy that all interrupts are to be done as PCI interrupts */
126         configbyte = 0xFF; /* bitmask, one bit per event, 1 = PCI interrupt, 0 = ISA interrupt */
127         pci_write_config_byte(dev, 0x50, configbyte); /* PCI Interrupt Routing Register */
128 
129         /* Register the interrupt handler */
130         dprintk(KERN_DEBUG "Requesting interrupt %i \n",dev->irq);
131         if ((ret = request_irq(dev->irq, i82092aa_interrupt, IRQF_SHARED, "i82092aa", i82092aa_interrupt))) {
132                 printk(KERN_ERR "i82092aa: Failed to register IRQ %d, aborting\n", dev->irq);
133                 goto err_out_free_res;
134         }
135 
136         for (i = 0; i<socket_count; i++) {
137                 sockets[i].socket.dev.parent = &dev->dev;
138                 sockets[i].socket.ops = &i82092aa_operations;
139                 sockets[i].socket.resource_ops = &pccard_nonstatic_ops;
140                 ret = pcmcia_register_socket(&sockets[i].socket);
141                 if (ret) {
142                         goto err_out_free_sockets;
143                 }
144         }
145 
146         leave("i82092aa_pci_probe");
147         return 0;
148 
149 err_out_free_sockets:
150         if (i) {
151                 for (i--;i>=0;i--) {
152                         pcmcia_unregister_socket(&sockets[i].socket);
153                 }
154         }
155         free_irq(dev->irq, i82092aa_interrupt);
156 err_out_free_res:
157         release_region(pci_resource_start(dev, 0), 2);
158 err_out_disable:
159         pci_disable_device(dev);
160         return ret;                     
161 }
162 
163 static void i82092aa_pci_remove(struct pci_dev *dev)
164 {
165         int i;
166 
167         enter("i82092aa_pci_remove");
168         
169         free_irq(dev->irq, i82092aa_interrupt);
170 
171         for (i = 0; i < socket_count; i++)
172                 pcmcia_unregister_socket(&sockets[i].socket);
173 
174         leave("i82092aa_pci_remove");
175 }
176 
177 static DEFINE_SPINLOCK(port_lock);
178 
179 /* basic value read/write functions */
180 
181 static unsigned char indirect_read(int socket, unsigned short reg)
182 {
183         unsigned short int port;
184         unsigned char val;
185         unsigned long flags;
186         spin_lock_irqsave(&port_lock,flags);
187         reg += socket * 0x40;
188         port = sockets[socket].io_base;
189         outb(reg,port);
190         val = inb(port+1);
191         spin_unlock_irqrestore(&port_lock,flags);
192         return val;
193 }
194 
195 #if 0
196 static unsigned short indirect_read16(int socket, unsigned short reg)
197 {
198         unsigned short int port;
199         unsigned short tmp;
200         unsigned long flags;
201         spin_lock_irqsave(&port_lock,flags);
202         reg  = reg + socket * 0x40;
203         port = sockets[socket].io_base;
204         outb(reg,port);
205         tmp = inb(port+1);
206         reg++;
207         outb(reg,port);
208         tmp = tmp | (inb(port+1)<<8);
209         spin_unlock_irqrestore(&port_lock,flags);
210         return tmp;
211 }
212 #endif
213 
214 static void indirect_write(int socket, unsigned short reg, unsigned char value)
215 {
216         unsigned short int port;
217         unsigned long flags;
218         spin_lock_irqsave(&port_lock,flags);
219         reg = reg + socket * 0x40;
220         port = sockets[socket].io_base; 
221         outb(reg,port);
222         outb(value,port+1);
223         spin_unlock_irqrestore(&port_lock,flags);
224 }
225 
226 static void indirect_setbit(int socket, unsigned short reg, unsigned char mask)
227 {
228         unsigned short int port;
229         unsigned char val;
230         unsigned long flags;
231         spin_lock_irqsave(&port_lock,flags);
232         reg = reg + socket * 0x40;
233         port = sockets[socket].io_base; 
234         outb(reg,port);
235         val = inb(port+1);
236         val |= mask;
237         outb(reg,port);
238         outb(val,port+1);
239         spin_unlock_irqrestore(&port_lock,flags);
240 }
241 
242 
243 static void indirect_resetbit(int socket, unsigned short reg, unsigned char mask)
244 {
245         unsigned short int port;
246         unsigned char val;
247         unsigned long flags;
248         spin_lock_irqsave(&port_lock,flags);
249         reg = reg + socket * 0x40;
250         port = sockets[socket].io_base; 
251         outb(reg,port);
252         val = inb(port+1);
253         val &= ~mask;
254         outb(reg,port);
255         outb(val,port+1);
256         spin_unlock_irqrestore(&port_lock,flags);
257 }
258 
259 static void indirect_write16(int socket, unsigned short reg, unsigned short value)
260 {
261         unsigned short int port;
262         unsigned char val;
263         unsigned long flags;
264         spin_lock_irqsave(&port_lock,flags);
265         reg = reg + socket * 0x40;
266         port = sockets[socket].io_base; 
267         
268         outb(reg,port);
269         val = value & 255;
270         outb(val,port+1);
271         
272         reg++;
273         
274         outb(reg,port);
275         val = value>>8;
276         outb(val,port+1);
277         spin_unlock_irqrestore(&port_lock,flags);
278 }
279 
280 /* simple helper functions */
281 /* External clock time, in nanoseconds.  120 ns = 8.33 MHz */
282 static int cycle_time = 120;
283 
284 static int to_cycles(int ns)
285 {
286         if (cycle_time!=0)
287                 return ns/cycle_time;
288         else
289                 return 0;
290 }
291     
292 
293 /* Interrupt handler functionality */
294 
295 static irqreturn_t i82092aa_interrupt(int irq, void *dev)
296 {
297         int i;
298         int loopcount = 0;
299         int handled = 0;
300 
301         unsigned int events, active=0;
302         
303 /*      enter("i82092aa_interrupt");*/
304         
305         while (1) {
306                 loopcount++;
307                 if (loopcount>20) {
308                         printk(KERN_ERR "i82092aa: infinite eventloop in interrupt \n");
309                         break;
310                 }
311                 
312                 active = 0;
313                 
314                 for (i=0;i<socket_count;i++) {
315                         int csc;
316                         if (sockets[i].card_state==0) /* Inactive socket, should not happen */
317                                 continue;
318                         
319                         csc = indirect_read(i,I365_CSC); /* card status change register */
320                         
321                         if (csc==0)  /* no events on this socket */
322                                 continue;
323                         handled = 1;
324                         events = 0;
325                          
326                         if (csc & I365_CSC_DETECT) {
327                                 events |= SS_DETECT;
328                                 printk("Card detected in socket %i!\n",i);
329                          }
330                         
331                         if (indirect_read(i,I365_INTCTL) & I365_PC_IOCARD) { 
332                                 /* For IO/CARDS, bit 0 means "read the card" */
333                                 events |= (csc & I365_CSC_STSCHG) ? SS_STSCHG : 0; 
334                         } else {
335                                 /* Check for battery/ready events */
336                                 events |= (csc & I365_CSC_BVD1) ? SS_BATDEAD : 0;
337                                 events |= (csc & I365_CSC_BVD2) ? SS_BATWARN : 0;
338                                 events |= (csc & I365_CSC_READY) ? SS_READY : 0;
339                         }
340                         
341                         if (events) {
342                                 pcmcia_parse_events(&sockets[i].socket, events);
343                         }
344                         active |= events;
345                 }
346                                 
347                 if (active==0) /* no more events to handle */
348                         break;                          
349                 
350         }
351         return IRQ_RETVAL(handled);
352 /*      leave("i82092aa_interrupt");*/
353 }
354 
355 
356 
357 /* socket functions */
358 
359 static int card_present(int socketno)
360 {       
361         unsigned int val;
362         enter("card_present");
363         
364         if ((socketno<0) || (socketno >= MAX_SOCKETS))
365                 return 0;
366         if (sockets[socketno].io_base == 0)
367                 return 0;
368 
369                 
370         val = indirect_read(socketno, 1); /* Interface status register */
371         if ((val&12)==12) {
372                 leave("card_present 1");
373                 return 1;
374         }
375                 
376         leave("card_present 0");
377         return 0;
378 }
379 
380 static void set_bridge_state(int sock)
381 {
382         enter("set_bridge_state");
383         indirect_write(sock, I365_GBLCTL,0x00);
384         indirect_write(sock, I365_GENCTL,0x00);
385         
386         indirect_setbit(sock, I365_INTCTL,0x08);
387         leave("set_bridge_state");
388 }
389 
390 
391 
392 
393 
394       
395 static int i82092aa_init(struct pcmcia_socket *sock)
396 {
397         int i;
398         struct resource res = { .start = 0, .end = 0x0fff };
399         pccard_io_map io = { 0, 0, 0, 0, 1 };
400         pccard_mem_map mem = { .res = &res, };
401         
402         enter("i82092aa_init");
403                         
404         for (i = 0; i < 2; i++) {
405                 io.map = i;
406                 i82092aa_set_io_map(sock, &io);
407         }
408         for (i = 0; i < 5; i++) {
409                 mem.map = i;
410                 i82092aa_set_mem_map(sock, &mem);
411         }
412         
413         leave("i82092aa_init");
414         return 0;
415 }
416                                                                                                                                                                                                                                               
417 static int i82092aa_get_status(struct pcmcia_socket *socket, u_int *value)
418 {
419         unsigned int sock = container_of(socket, struct socket_info, socket)->number;
420         unsigned int status;
421         
422         enter("i82092aa_get_status");
423         
424         status = indirect_read(sock,I365_STATUS); /* Interface Status Register */
425         *value = 0;
426         
427         if ((status & I365_CS_DETECT) == I365_CS_DETECT) {
428                 *value |= SS_DETECT;
429         }
430                 
431         /* IO cards have a different meaning of bits 0,1 */
432         /* Also notice the inverse-logic on the bits */
433          if (indirect_read(sock, I365_INTCTL) & I365_PC_IOCARD) {
434                 /* IO card */
435                 if (!(status & I365_CS_STSCHG))
436                         *value |= SS_STSCHG;
437          } else { /* non I/O card */
438                 if (!(status & I365_CS_BVD1))
439                         *value |= SS_BATDEAD;
440                 if (!(status & I365_CS_BVD2))
441                         *value |= SS_BATWARN;
442                         
443          }
444          
445          if (status & I365_CS_WRPROT)
446                 (*value) |= SS_WRPROT;  /* card is write protected */
447          
448          if (status & I365_CS_READY)
449                 (*value) |= SS_READY;    /* card is not busy */
450                 
451          if (status & I365_CS_POWERON)
452                 (*value) |= SS_POWERON;  /* power is applied to the card */
453 
454 
455         leave("i82092aa_get_status");
456         return 0;
457 }
458 
459 
460 static int i82092aa_set_socket(struct pcmcia_socket *socket, socket_state_t *state) 
461 {
462         unsigned int sock = container_of(socket, struct socket_info, socket)->number;
463         unsigned char reg;
464         
465         enter("i82092aa_set_socket");
466         
467         /* First, set the global controller options */
468         
469         set_bridge_state(sock);
470         
471         /* Values for the IGENC register */
472         
473         reg = 0;
474         if (!(state->flags & SS_RESET))         /* The reset bit has "inverse" logic */
475                 reg = reg | I365_PC_RESET;  
476         if (state->flags & SS_IOCARD) 
477                 reg = reg | I365_PC_IOCARD;
478                 
479         indirect_write(sock,I365_INTCTL,reg); /* IGENC, Interrupt and General Control Register */
480         
481         /* Power registers */
482         
483         reg = I365_PWR_NORESET; /* default: disable resetdrv on resume */
484         
485         if (state->flags & SS_PWR_AUTO) {
486                 printk("Auto power\n");
487                 reg |= I365_PWR_AUTO;   /* automatic power mngmnt */
488         }
489         if (state->flags & SS_OUTPUT_ENA) {
490                 printk("Power Enabled \n");
491                 reg |= I365_PWR_OUT;    /* enable power */
492         }
493         
494         switch (state->Vcc) {
495                 case 0: 
496                         break;
497                 case 50: 
498                         printk("setting voltage to Vcc to 5V on socket %i\n",sock);
499                         reg |= I365_VCC_5V;
500                         break;
501                 default:
502                         printk("i82092aa: i82092aa_set_socket called with invalid VCC power value: %i ", state->Vcc);
503                         leave("i82092aa_set_socket");
504                         return -EINVAL;
505         }
506         
507         
508         switch (state->Vpp) {
509                 case 0: 
510                         printk("not setting Vpp on socket %i\n",sock);
511                         break;
512                 case 50: 
513                         printk("setting Vpp to 5.0 for socket %i\n",sock);
514                         reg |= I365_VPP1_5V | I365_VPP2_5V;
515                         break;
516                 case 120: 
517                         printk("setting Vpp to 12.0\n");
518                         reg |= I365_VPP1_12V | I365_VPP2_12V;
519                         break;
520                 default:
521                         printk("i82092aa: i82092aa_set_socket called with invalid VPP power value: %i ", state->Vcc);
522                         leave("i82092aa_set_socket");
523                         return -EINVAL;
524         }
525         
526         if (reg != indirect_read(sock,I365_POWER)) /* only write if changed */
527                 indirect_write(sock,I365_POWER,reg);
528                 
529         /* Enable specific interrupt events */
530         
531         reg = 0x00;
532         if (state->csc_mask & SS_DETECT) {
533                 reg |= I365_CSC_DETECT;
534         }
535         if (state->flags & SS_IOCARD) {
536                 if (state->csc_mask & SS_STSCHG)
537                         reg |= I365_CSC_STSCHG;
538         } else {
539                 if (state->csc_mask & SS_BATDEAD) 
540                         reg |= I365_CSC_BVD1;
541                 if (state->csc_mask & SS_BATWARN) 
542                         reg |= I365_CSC_BVD2;
543                 if (state->csc_mask & SS_READY) 
544                         reg |= I365_CSC_READY; 
545                                         
546         }
547         
548         /* now write the value and clear the (probably bogus) pending stuff by doing a dummy read*/
549         
550         indirect_write(sock,I365_CSCINT,reg);
551         (void)indirect_read(sock,I365_CSC);
552 
553         leave("i82092aa_set_socket");
554         return 0;
555 }
556 
557 static int i82092aa_set_io_map(struct pcmcia_socket *socket, struct pccard_io_map *io)
558 {
559         unsigned int sock = container_of(socket, struct socket_info, socket)->number;
560         unsigned char map, ioctl;
561         
562         enter("i82092aa_set_io_map");
563         
564         map = io->map;
565         
566         /* Check error conditions */    
567         if (map > 1) {
568                 leave("i82092aa_set_io_map with invalid map");
569                 return -EINVAL;
570         }
571         if ((io->start > 0xffff) || (io->stop > 0xffff) || (io->stop < io->start)){
572                 leave("i82092aa_set_io_map with invalid io");
573                 return -EINVAL;
574         }
575 
576         /* Turn off the window before changing anything */ 
577         if (indirect_read(sock, I365_ADDRWIN) & I365_ENA_IO(map))
578                 indirect_resetbit(sock, I365_ADDRWIN, I365_ENA_IO(map));
579 
580 /*      printk("set_io_map: Setting range to %x - %x \n",io->start,io->stop);  */
581         
582         /* write the new values */
583         indirect_write16(sock,I365_IO(map)+I365_W_START,io->start);             
584         indirect_write16(sock,I365_IO(map)+I365_W_STOP,io->stop);               
585                         
586         ioctl = indirect_read(sock,I365_IOCTL) & ~I365_IOCTL_MASK(map);
587         
588         if (io->flags & (MAP_16BIT|MAP_AUTOSZ))
589                 ioctl |= I365_IOCTL_16BIT(map);
590                 
591         indirect_write(sock,I365_IOCTL,ioctl);
592         
593         /* Turn the window back on if needed */
594         if (io->flags & MAP_ACTIVE)
595                 indirect_setbit(sock,I365_ADDRWIN,I365_ENA_IO(map));
596                         
597         leave("i82092aa_set_io_map");   
598         return 0;
599 }
600 
601 static int i82092aa_set_mem_map(struct pcmcia_socket *socket, struct pccard_mem_map *mem)
602 {
603         struct socket_info *sock_info = container_of(socket, struct socket_info, socket);
604         unsigned int sock = sock_info->number;
605         struct pci_bus_region region;
606         unsigned short base, i;
607         unsigned char map;
608         
609         enter("i82092aa_set_mem_map");
610 
611         pcibios_resource_to_bus(sock_info->dev->bus, &region, mem->res);
612         
613         map = mem->map;
614         if (map > 4) {
615                 leave("i82092aa_set_mem_map: invalid map");
616                 return -EINVAL;
617         }
618         
619         
620         if ( (mem->card_start > 0x3ffffff) || (region.start > region.end) ||
621              (mem->speed > 1000) ) {
622                 leave("i82092aa_set_mem_map: invalid address / speed");
623                 printk("invalid mem map for socket %i: %llx to %llx with a "
624                         "start of %x\n",
625                         sock,
626                         (unsigned long long)region.start,
627                         (unsigned long long)region.end,
628                         mem->card_start);
629                 return -EINVAL;
630         }
631         
632         /* Turn off the window before changing anything */
633         if (indirect_read(sock, I365_ADDRWIN) & I365_ENA_MEM(map))
634                       indirect_resetbit(sock, I365_ADDRWIN, I365_ENA_MEM(map));
635                          
636                          
637 /*      printk("set_mem_map: Setting map %i range to %x - %x on socket %i, speed is %i, active = %i \n",map, region.start,region.end,sock,mem->speed,mem->flags & MAP_ACTIVE);  */
638 
639         /* write the start address */
640         base = I365_MEM(map);
641         i = (region.start >> 12) & 0x0fff;
642         if (mem->flags & MAP_16BIT) 
643                 i |= I365_MEM_16BIT;
644         if (mem->flags & MAP_0WS)
645                 i |= I365_MEM_0WS;      
646         indirect_write16(sock,base+I365_W_START,i);
647                                
648         /* write the stop address */
649         
650         i= (region.end >> 12) & 0x0fff;
651         switch (to_cycles(mem->speed)) {
652                 case 0:
653                         break;
654                 case 1:
655                         i |= I365_MEM_WS0;
656                         break;
657                 case 2:
658                         i |= I365_MEM_WS1;
659                         break;
660                 default:
661                         i |= I365_MEM_WS1 | I365_MEM_WS0;
662                         break;
663         }
664         
665         indirect_write16(sock,base+I365_W_STOP,i);
666         
667         /* card start */
668         
669         i = ((mem->card_start - region.start) >> 12) & 0x3fff;
670         if (mem->flags & MAP_WRPROT)
671                 i |= I365_MEM_WRPROT;
672         if (mem->flags & MAP_ATTRIB) {
673 /*              printk("requesting attribute memory for socket %i\n",sock);*/
674                 i |= I365_MEM_REG;
675         } else {
676 /*              printk("requesting normal memory for socket %i\n",sock);*/
677         }
678         indirect_write16(sock,base+I365_W_OFF,i);
679         
680         /* Enable the window if necessary */
681         if (mem->flags & MAP_ACTIVE)
682                 indirect_setbit(sock, I365_ADDRWIN, I365_ENA_MEM(map));
683                     
684         leave("i82092aa_set_mem_map");
685         return 0;
686 }
687 
688 static int i82092aa_module_init(void)
689 {
690         return pci_register_driver(&i82092aa_pci_driver);
691 }
692 
693 static void i82092aa_module_exit(void)
694 {
695         enter("i82092aa_module_exit");
696         pci_unregister_driver(&i82092aa_pci_driver);
697         if (sockets[0].io_base>0)
698                          release_region(sockets[0].io_base, 2);
699         leave("i82092aa_module_exit");
700 }
701 
702 module_init(i82092aa_module_init);
703 module_exit(i82092aa_module_exit);
704 
705 

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