drivers/input/serio/gscps2.c

   1 /*
   2  * drivers/input/serio/gscps2.c
   3  *
   4  * Copyright (c) 2004-2006 Helge Deller <deller@gmx.de>
   5  * Copyright (c) 2002 Laurent Canet <canetl@esiee.fr>
   6  * Copyright (c) 2002 Thibaut Varene <varenet@parisc-linux.org>
   7  *
   8  * Pieces of code based on linux-2.4's hp_mouse.c & hp_keyb.c
   9  *      Copyright (c) 1999 Alex deVries <alex@onefishtwo.ca>
  10  *      Copyright (c) 1999-2000 Philipp Rumpf <prumpf@tux.org>
  11  *      Copyright (c) 2000 Xavier Debacker <debackex@esiee.fr>
  12  *      Copyright (c) 2000-2001 Thomas Marteau <marteaut@esiee.fr>
  13  *
  14  * HP GSC PS/2 port driver, found in PA/RISC Workstations
  15  *
  16  * This file is subject to the terms and conditions of the GNU General Public
  17  * License.  See the file "COPYING" in the main directory of this archive
  18  * for more details.
  19  *
  20  * TODO:
  21  * - Dino testing (did HP ever shipped a machine on which this port
  22  *                 was usable/enabled ?)
  23  */
  24
  25 #include <linux/init.h>
  26 #include <linux/module.h>
  27 #include <linux/serio.h>
  28 #include <linux/input.h>
  29 #include <linux/interrupt.h>
  30 #include <linux/spinlock.h>
  31 #include <linux/delay.h>
  32 #include <linux/ioport.h>
  33 #include <linux/pci_ids.h>
  34
  35 #include <asm/irq.h>
  36 #include <asm/io.h>
  37 #include <asm/parisc-device.h>
  38
  39 MODULE_AUTHOR("Laurent Canet <canetl@esiee.fr>, Thibaut Varene <varenet@parisc-linux.org>, Helge Deller <deller@gmx.de>");
  40 MODULE_DESCRIPTION("HP GSC PS2 port driver");
  41 MODULE_LICENSE("GPL");
  42 MODULE_DEVICE_TABLE(parisc, gscps2_device_tbl);
  43
  44 #define PFX "gscps2.c: "
  45
  46 /*
  47  * Driver constants
  48  */
  49
  50 /* various constants */
  51 #define ENABLE                  1
  52 #define DISABLE                 0
  53
  54 #define GSC_DINO_OFFSET         0x0800  /* offset for DINO controller versus LASI one */
  55
  56 /* PS/2 IO port offsets */
  57 #define GSC_ID                  0x00    /* device ID offset (see: GSC_ID_XXX) */
  58 #define GSC_RESET               0x00    /* reset port offset */
  59 #define GSC_RCVDATA             0x04    /* receive port offset */
  60 #define GSC_XMTDATA             0x04    /* transmit port offset */
  61 #define GSC_CONTROL             0x08    /* see: Control register bits */
  62 #define GSC_STATUS              0x0C    /* see: Status register bits */
  63
  64 /* Control register bits */
  65 #define GSC_CTRL_ENBL           0x01    /* enable interface */
  66 #define GSC_CTRL_LPBXR          0x02    /* loopback operation */
  67 #define GSC_CTRL_DIAG           0x20    /* directly control clock/data line */
  68 #define GSC_CTRL_DATDIR         0x40    /* data line direct control */
  69 #define GSC_CTRL_CLKDIR         0x80    /* clock line direct control */
  70
  71 /* Status register bits */
  72 #define GSC_STAT_RBNE           0x01    /* Receive Buffer Not Empty */
  73 #define GSC_STAT_TBNE           0x02    /* Transmit Buffer Not Empty */
  74 #define GSC_STAT_TERR           0x04    /* Timeout Error */
  75 #define GSC_STAT_PERR           0x08    /* Parity Error */
  76 #define GSC_STAT_CMPINTR        0x10    /* Composite Interrupt = irq on any port */
  77 #define GSC_STAT_DATSHD         0x40    /* Data Line Shadow */
  78 #define GSC_STAT_CLKSHD         0x80    /* Clock Line Shadow */
  79
  80 /* IDs returned by GSC_ID port register */
  81 #define GSC_ID_KEYBOARD         0       /* device ID values */
  82 #define GSC_ID_MOUSE            1
  83
  84
  85 static irqreturn_t gscps2_interrupt(int irq, void *dev);
  86
  87 #define BUFFER_SIZE 0x0f
  88
  89 /* GSC PS/2 port device struct */
  90 struct gscps2port {
  91         struct list_head node;
  92         struct parisc_device *padev;
  93         struct serio *port;
  94         spinlock_t lock;
  95         char *addr;
  96         u8 act, append; /* position in buffer[] */
  97         struct {
  98                 u8 data;
  99                 u8 str;
 100         } buffer[BUFFER_SIZE+1];
 101         int id;
 102 };
 103
 104 /*
 105  * Various HW level routines
 106  */
 107
 108 #define gscps2_readb_input(x)           readb((x)+GSC_RCVDATA)
 109 #define gscps2_readb_control(x)         readb((x)+GSC_CONTROL)
 110 #define gscps2_readb_status(x)          readb((x)+GSC_STATUS)
 111 #define gscps2_writeb_control(x, y)     writeb((x), (y)+GSC_CONTROL)
 112
 113
 114 /*
 115  * wait_TBE() - wait for Transmit Buffer Empty
 116  */
 117
 118 static int wait_TBE(char *addr)
 119 {
 120         int timeout = 25000; /* device is expected to react within 250 msec */
 121         while (gscps2_readb_status(addr) & GSC_STAT_TBNE) {
 122                 if (!--timeout)
 123                         return 0;       /* This should not happen */
 124                 udelay(10);
 125         }
 126         return 1;
 127 }
 128
 129
 130 /*
 131  * gscps2_flush() - flush the receive buffer
 132  */
 133
 134 static void gscps2_flush(struct gscps2port *ps2port)
 135 {
 136         while (gscps2_readb_status(ps2port->addr) & GSC_STAT_RBNE)
 137                 gscps2_readb_input(ps2port->addr);
 138         ps2port->act = ps2port->append = 0;
 139 }
 140
 141 /*
 142  * gscps2_writeb_output() - write a byte to the port
 143  *
 144  * returns 1 on success, 0 on error
 145  */
 146
 147 static inline int gscps2_writeb_output(struct gscps2port *ps2port, u8 data)
 148 {
 149         unsigned long flags;
 150         char *addr = ps2port->addr;
 151
 152         if (!wait_TBE(addr)) {
 153                 printk(KERN_DEBUG PFX "timeout - could not write byte %#x\n", data);
 154                 return 0;
 155         }
 156
 157         while (gscps2_readb_status(ps2port->addr) & GSC_STAT_RBNE)
 158                 /* wait */;
 159
 160         spin_lock_irqsave(&ps2port->lock, flags);
 161         writeb(data, addr+GSC_XMTDATA);
 162         spin_unlock_irqrestore(&ps2port->lock, flags);
 163
 164         /* this is ugly, but due to timing of the port it seems to be necessary. */
 165         mdelay(6);
 166
 167         /* make sure any received data is returned as fast as possible */
 168         /* this is important e.g. when we set the LEDs on the keyboard */
 169         gscps2_interrupt(0, NULL);
 170
 171         return 1;
 172 }
 173
 174
 175 /*
 176  * gscps2_enable() - enables or disables the port
 177  */
 178
 179 static void gscps2_enable(struct gscps2port *ps2port, int enable)
 180 {
 181         unsigned long flags;
 182         u8 data;
 183
 184         /* now enable/disable the port */
 185         spin_lock_irqsave(&ps2port->lock, flags);
 186         gscps2_flush(ps2port);
 187         data = gscps2_readb_control(ps2port->addr);
 188         if (enable)
 189                 data |= GSC_CTRL_ENBL;
 190         else
 191                 data &= ~GSC_CTRL_ENBL;
 192         gscps2_writeb_control(data, ps2port->addr);
 193         spin_unlock_irqrestore(&ps2port->lock, flags);
 194         wait_TBE(ps2port->addr);
 195         gscps2_flush(ps2port);
 196 }
 197
 198 /*
 199  * gscps2_reset() - resets the PS/2 port
 200  */
 201
 202 static void gscps2_reset(struct gscps2port *ps2port)
 203 {
 204         char *addr = ps2port->addr;
 205         unsigned long flags;
 206
 207         /* reset the interface */
 208         spin_lock_irqsave(&ps2port->lock, flags);
 209         gscps2_flush(ps2port);
 210         writeb(0xff, addr+GSC_RESET);
 211         gscps2_flush(ps2port);
 212         spin_unlock_irqrestore(&ps2port->lock, flags);
 213 }
 214
 215 static LIST_HEAD(ps2port_list);
 216
 217 /**
 218  * gscps2_interrupt() - Interruption service routine
 219  *
 220  * This function reads received PS/2 bytes and processes them on
 221  * all interfaces.
 222  * The problematic part here is, that the keyboard and mouse PS/2 port
 223  * share the same interrupt and it's not possible to send data if any
 224  * one of them holds input data. To solve this problem we try to receive
 225  * the data as fast as possible and handle the reporting to the upper layer
 226  * later.
 227  */
 228
 229 static irqreturn_t gscps2_interrupt(int irq, void *dev)
 230 {
 231         struct gscps2port *ps2port;
 232
 233         list_for_each_entry(ps2port, &ps2port_list, node) {
 234
 235           unsigned long flags;
 236           spin_lock_irqsave(&ps2port->lock, flags);
 237
 238           while ( (ps2port->buffer[ps2port->append].str =
 239                    gscps2_readb_status(ps2port->addr)) & GSC_STAT_RBNE ) {
 240                 ps2port->buffer[ps2port->append].data =
 241                                 gscps2_readb_input(ps2port->addr);
 242                 ps2port->append = ((ps2port->append+1) & BUFFER_SIZE);
 243           }
 244
 245           spin_unlock_irqrestore(&ps2port->lock, flags);
 246
 247         } /* list_for_each_entry */
 248
 249         /* all data was read from the ports - now report the data to upper layer */
 250
 251         list_for_each_entry(ps2port, &ps2port_list, node) {
 252
 253           while (ps2port->act != ps2port->append) {
 254
 255             unsigned int rxflags;
 256             u8 data, status;
 257
 258             /* Did new data arrived while we read existing data ?
 259                If yes, exit now and let the new irq handler start over again */
 260             if (gscps2_readb_status(ps2port->addr) & GSC_STAT_CMPINTR)
 261                 return IRQ_HANDLED;
 262
 263             status = ps2port->buffer[ps2port->act].str;
 264             data   = ps2port->buffer[ps2port->act].data;
 265
 266             ps2port->act = ((ps2port->act+1) & BUFFER_SIZE);
 267             rxflags =   ((status & GSC_STAT_TERR) ? SERIO_TIMEOUT : 0 ) |
 268                         ((status & GSC_STAT_PERR) ? SERIO_PARITY  : 0 );
 269
 270             serio_interrupt(ps2port->port, data, rxflags);
 271
 272           } /* while() */
 273
 274         } /* list_for_each_entry */
 275
 276         return IRQ_HANDLED;
 277 }
 278
 279
 280 /*
 281  * gscps2_write() - send a byte out through the aux interface.
 282  */
 283
 284 static int gscps2_write(struct serio *port, unsigned char data)
 285 {
 286         struct gscps2port *ps2port = port->port_data;
 287
 288         if (!gscps2_writeb_output(ps2port, data)) {
 289                 printk(KERN_DEBUG PFX "sending byte %#x failed.\n", data);
 290                 return -1;
 291         }
 292         return 0;
 293 }
 294
 295 /*
 296  * gscps2_open() is called when a port is opened by the higher layer.
 297  * It resets and enables the port.
 298  */
 299
 300 static int gscps2_open(struct serio *port)
 301 {
 302         struct gscps2port *ps2port = port->port_data;
 303
 304         gscps2_reset(ps2port);
 305
 306         /* enable it */
 307         gscps2_enable(ps2port, ENABLE);
 308
 309         gscps2_interrupt(0, NULL);
 310
 311         return 0;
 312 }
 313
 314 /*
 315  * gscps2_close() disables the port
 316  */
 317
 318 static void gscps2_close(struct serio *port)
 319 {
 320         struct gscps2port *ps2port = port->port_data;
 321         gscps2_enable(ps2port, DISABLE);
 322 }
 323
 324 /**
 325  * gscps2_probe() - Probes PS2 devices
 326  * @return: success/error report
 327  */
 328
 329 static int __init gscps2_probe(struct parisc_device *dev)
 330 {
 331         struct gscps2port *ps2port;
 332         struct serio *serio;
 333         unsigned long hpa = dev->hpa.start;
 334         int ret;
 335
 336         if (!dev->irq)
 337                 return -ENODEV;
 338
 339         /* Offset for DINO PS/2. Works with LASI even */
 340         if (dev->id.sversion == 0x96)
 341                 hpa += GSC_DINO_OFFSET;
 342
 343         ps2port = kzalloc(sizeof(struct gscps2port), GFP_KERNEL);
 344         serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
 345         if (!ps2port || !serio) {
 346                 ret = -ENOMEM;
 347                 goto fail_nomem;
 348         }
 349
 350         dev_set_drvdata(&dev->dev, ps2port);
 351
 352         ps2port->port = serio;
 353         ps2port->padev = dev;
 354         ps2port->addr = ioremap_nocache(hpa, GSC_STATUS + 4);
 355         spin_lock_init(&ps2port->lock);
 356
 357         gscps2_reset(ps2port);
 358         ps2port->id = readb(ps2port->addr + GSC_ID) & 0x0f;
 359
 360         snprintf(serio->name, sizeof(serio->name), "GSC PS/2 %s",
 361                  (ps2port->id == GSC_ID_KEYBOARD) ? "keyboard" : "mouse");
 362         strlcpy(serio->phys, dev_name(&dev->dev), sizeof(serio->phys));
 363         serio->id.type          = SERIO_8042;
 364         serio->write            = gscps2_write;
 365         serio->open             = gscps2_open;
 366         serio->close            = gscps2_close;
 367         serio->port_data        = ps2port;
 368         serio->dev.parent       = &dev->dev;
 369
 370         ret = -EBUSY;
 371         if (request_irq(dev->irq, gscps2_interrupt, IRQF_SHARED, ps2port->port->name, ps2port))
 372                 goto fail_miserably;
 373
 374         if (ps2port->id != GSC_ID_KEYBOARD && ps2port->id != GSC_ID_MOUSE) {
 375                 printk(KERN_WARNING PFX "Unsupported PS/2 port at 0x%08lx (id=%d) ignored\n",
 376                                 hpa, ps2port->id);
 377                 ret = -ENODEV;
 378                 goto fail;
 379         }
 380
 381 #if 0
 382         if (!request_mem_region(hpa, GSC_STATUS + 4, ps2port->port.name))
 383                 goto fail;
 384 #endif
 385
 386         printk(KERN_INFO "serio: %s port at 0x%p irq %d @ %s\n",
 387                 ps2port->port->name,
 388                 ps2port->addr,
 389                 ps2port->padev->irq,
 390                 ps2port->port->phys);
 391
 392         serio_register_port(ps2port->port);
 393
 394         list_add_tail(&ps2port->node, &ps2port_list);
 395
 396         return 0;
 397
 398 fail:
 399         free_irq(dev->irq, ps2port);
 400
 401 fail_miserably:
 402         iounmap(ps2port->addr);
 403         release_mem_region(dev->hpa.start, GSC_STATUS + 4);
 404
 405 fail_nomem:
 406         kfree(ps2port);
 407         kfree(serio);
 408         return ret;
 409 }
 410
 411 /**
 412  * gscps2_remove() - Removes PS2 devices
 413  * @return: success/error report
 414  */
 415
 416 static int __devexit gscps2_remove(struct parisc_device *dev)
 417 {
 418         struct gscps2port *ps2port = dev_get_drvdata(&dev->dev);
 419
 420         serio_unregister_port(ps2port->port);
 421         free_irq(dev->irq, ps2port);
 422         gscps2_flush(ps2port);
 423         list_del(&ps2port->node);
 424         iounmap(ps2port->addr);
 425 #if 0
 426         release_mem_region(dev->hpa, GSC_STATUS + 4);
 427 #endif
 428         dev_set_drvdata(&dev->dev, NULL);
 429         kfree(ps2port);
 430         return 0;
 431 }
 432
 433
 434 static struct parisc_device_id gscps2_device_tbl[] = {
 435         { HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x00084 }, /* LASI PS/2 */
 436 #ifdef DINO_TESTED
 437         { HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x00096 }, /* DINO PS/2 */
 438 #endif
 439         { 0, }  /* 0 terminated list */
 440 };
 441
 442 static struct parisc_driver parisc_ps2_driver = {
 443         .name           = "gsc_ps2",
 444         .id_table       = gscps2_device_tbl,
 445         .probe          = gscps2_probe,
 446         .remove         = gscps2_remove,
 447 };
 448
 449 static int __init gscps2_init(void)
 450 {
 451         register_parisc_driver(&parisc_ps2_driver);
 452         return 0;
 453 }
 454
 455 static void __exit gscps2_exit(void)
 456 {
 457         unregister_parisc_driver(&parisc_ps2_driver);
 458 }
 459
 460
 461 module_init(gscps2_init);
 462 module_exit(gscps2_exit);
 463