drivers/input/serio/gscps2.c

   1 /*
   2  * drivers/input/serio/gscps2.c
   3  *
   4  * Copyright (c) 2004 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/config.h>
  26 #include <linux/init.h>
  27 #include <linux/module.h>
  28 #include <linux/serio.h>
  29 #include <linux/input.h>
  30 #include <linux/interrupt.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/delay.h>
  33 #include <linux/ioport.h>
  34 #include <linux/pci_ids.h>
  35
  36 #include <asm/irq.h>
  37 #include <asm/io.h>
  38 #include <asm/parisc-device.h>
  39
  40 MODULE_AUTHOR("Laurent Canet <canetl@esiee.fr>, Thibaut Varene <varenet@parisc-linux.org>, Helge Deller <deller@gmx.de>");
  41 MODULE_DESCRIPTION("HP GSC PS2 port driver");
  42 MODULE_LICENSE("GPL");
  43 MODULE_DEVICE_TABLE(parisc, gscps2_device_tbl);
  44
  45 #define PFX "gscps2.c: "
  46
  47 /*
  48  * Driver constants
  49  */
  50
  51 /* various constants */
  52 #define ENABLE                  1
  53 #define DISABLE                 0
  54
  55 #define GSC_DINO_OFFSET         0x0800  /* offset for DINO controller versus LASI one */
  56
  57 /* PS/2 IO port offsets */
  58 #define GSC_ID                  0x00    /* device ID offset (see: GSC_ID_XXX) */
  59 #define GSC_RESET               0x00    /* reset port offset */
  60 #define GSC_RCVDATA             0x04    /* receive port offset */
  61 #define GSC_XMTDATA             0x04    /* transmit port offset */
  62 #define GSC_CONTROL             0x08    /* see: Control register bits */
  63 #define GSC_STATUS              0x0C    /* see: Status register bits */
  64
  65 /* Control register bits */
  66 #define GSC_CTRL_ENBL           0x01    /* enable interface */
  67 #define GSC_CTRL_LPBXR          0x02    /* loopback operation */
  68 #define GSC_CTRL_DIAG           0x20    /* directly control clock/data line */
  69 #define GSC_CTRL_DATDIR         0x40    /* data line direct control */
  70 #define GSC_CTRL_CLKDIR         0x80    /* clock line direct control */
  71
  72 /* Status register bits */
  73 #define GSC_STAT_RBNE           0x01    /* Receive Buffer Not Empty */
  74 #define GSC_STAT_TBNE           0x02    /* Transmit Buffer Not Empty */
  75 #define GSC_STAT_TERR           0x04    /* Timeout Error */
  76 #define GSC_STAT_PERR           0x08    /* Parity Error */
  77 #define GSC_STAT_CMPINTR        0x10    /* Composite Interrupt = irq on any port */
  78 #define GSC_STAT_DATSHD         0x40    /* Data Line Shadow */
  79 #define GSC_STAT_CLKSHD         0x80    /* Clock Line Shadow */
  80
  81 /* IDs returned by GSC_ID port register */
  82 #define GSC_ID_KEYBOARD         0       /* device ID values */
  83 #define GSC_ID_MOUSE            1
  84
  85
  86 static irqreturn_t gscps2_interrupt(int irq, void *dev, struct pt_regs *regs);
  87
  88 #define BUFFER_SIZE 0x0f
  89
  90 /* GSC PS/2 port device struct */
  91 struct gscps2port {
  92         struct list_head node;
  93         struct parisc_device *padev;
  94         struct serio *port;
  95         spinlock_t lock;
  96         char *addr;
  97         u8 act, append; /* position in buffer[] */
  98         struct {
  99                 u8 data;
 100                 u8 str;
 101         } buffer[BUFFER_SIZE+1];
 102         int id;
 103 };
 104
 105 /*
 106  * Various HW level routines
 107  */
 108
 109 #define gscps2_readb_input(x)           readb((x)+GSC_RCVDATA)
 110 #define gscps2_readb_control(x)         readb((x)+GSC_CONTROL)
 111 #define gscps2_readb_status(x)          readb((x)+GSC_STATUS)
 112 #define gscps2_writeb_control(x, y)     writeb((x), (y)+GSC_CONTROL)
 113
 114
 115 /*
 116  * wait_TBE() - wait for Transmit Buffer Empty
 117  */
 118
 119 static int wait_TBE(char *addr)
 120 {
 121         int timeout = 25000; /* device is expected to react within 250 msec */
 122         while (gscps2_readb_status(addr) & GSC_STAT_TBNE) {
 123                 if (!--timeout)
 124                         return 0;       /* This should not happen */
 125                 udelay(10);
 126         }
 127         return 1;
 128 }
 129
 130
 131 /*
 132  * gscps2_flush() - flush the receive buffer
 133  */
 134
 135 static void gscps2_flush(struct gscps2port *ps2port)
 136 {
 137         while (gscps2_readb_status(ps2port->addr) & GSC_STAT_RBNE)
 138                 gscps2_readb_input(ps2port->addr);
 139         ps2port->act = ps2port->append = 0;
 140 }
 141
 142 /*
 143  * gscps2_writeb_output() - write a byte to the port
 144  *
 145  * returns 1 on sucess, 0 on error
 146  */
 147
 148 static inline int gscps2_writeb_output(struct gscps2port *ps2port, u8 data)
 149 {
 150         unsigned long flags;
 151         char *addr = ps2port->addr;
 152
 153         if (!wait_TBE(addr)) {
 154                 printk(KERN_DEBUG PFX "timeout - could not write byte %#x\n", data);
 155                 return 0;
 156         }
 157
 158         while (gscps2_readb_status(ps2port->addr) & GSC_STAT_RBNE)
 159                 /* wait */;
 160
 161         spin_lock_irqsave(&ps2port->lock, flags);
 162         writeb(data, addr+GSC_XMTDATA);
 163         spin_unlock_irqrestore(&ps2port->lock, flags);
 164
 165         /* this is ugly, but due to timing of the port it seems to be necessary. */
 166         mdelay(6);
 167
 168         /* make sure any received data is returned as fast as possible */
 169         /* this is important e.g. when we set the LEDs on the keyboard */
 170         gscps2_interrupt(0, NULL, NULL);
 171
 172         return 1;
 173 }
 174
 175
 176 /*
 177  * gscps2_enable() - enables or disables the port
 178  */
 179
 180 static void gscps2_enable(struct gscps2port *ps2port, int enable)
 181 {
 182         unsigned long flags;
 183         u8 data;
 184
 185         /* now enable/disable the port */
 186         spin_lock_irqsave(&ps2port->lock, flags);
 187         gscps2_flush(ps2port);
 188         data = gscps2_readb_control(ps2port->addr);
 189         if (enable)
 190                 data |= GSC_CTRL_ENBL;
 191         else
 192                 data &= ~GSC_CTRL_ENBL;
 193         gscps2_writeb_control(data, ps2port->addr);
 194         spin_unlock_irqrestore(&ps2port->lock, flags);
 195         wait_TBE(ps2port->addr);
 196         gscps2_flush(ps2port);
 197 }
 198
 199 /*
 200  * gscps2_reset() - resets the PS/2 port
 201  */
 202
 203 static void gscps2_reset(struct gscps2port *ps2port)
 204 {
 205         char *addr = ps2port->addr;
 206         unsigned long flags;
 207
 208         /* reset the interface */
 209         spin_lock_irqsave(&ps2port->lock, flags);
 210         gscps2_flush(ps2port);
 211         writeb(0xff, addr+GSC_RESET);
 212         gscps2_flush(ps2port);
 213         spin_unlock_irqrestore(&ps2port->lock, flags);
 214
 215         /* enable it */
 216         gscps2_enable(ps2port, ENABLE);
 217 }
 218
 219 static LIST_HEAD(ps2port_list);
 220
 221 /**
 222  * gscps2_interrupt() - Interruption service routine
 223  *
 224  * This function reads received PS/2 bytes and processes them on
 225  * all interfaces.
 226  * The problematic part here is, that the keyboard and mouse PS/2 port
 227  * share the same interrupt and it's not possible to send data if any
 228  * one of them holds input data. To solve this problem we try to receive
 229  * the data as fast as possible and handle the reporting to the upper layer
 230  * later.
 231  */
 232
 233 static irqreturn_t gscps2_interrupt(int irq, void *dev, struct pt_regs *regs)
 234 {
 235         struct gscps2port *ps2port;
 236
 237         list_for_each_entry(ps2port, &ps2port_list, node) {
 238
 239           unsigned long flags;
 240           spin_lock_irqsave(&ps2port->lock, flags);
 241
 242           while ( (ps2port->buffer[ps2port->append].str =
 243                    gscps2_readb_status(ps2port->addr)) & GSC_STAT_RBNE ) {
 244                 ps2port->buffer[ps2port->append].data =
 245                                 gscps2_readb_input(ps2port->addr);
 246                 ps2port->append = ((ps2port->append+1) & BUFFER_SIZE);
 247           }
 248
 249           spin_unlock_irqrestore(&ps2port->lock, flags);
 250
 251         } /* list_for_each_entry */
 252
 253         /* all data was read from the ports - now report the data to upper layer */
 254
 255         list_for_each_entry(ps2port, &ps2port_list, node) {
 256
 257           while (ps2port->act != ps2port->append) {
 258
 259             unsigned int rxflags;
 260             u8 data, status;
 261
 262             /* Did new data arrived while we read existing data ?
 263                If yes, exit now and let the new irq handler start over again */
 264             if (gscps2_readb_status(ps2port->addr) & GSC_STAT_CMPINTR)
 265                 return IRQ_HANDLED;
 266
 267             status = ps2port->buffer[ps2port->act].str;
 268             data   = ps2port->buffer[ps2port->act].data;
 269
 270             ps2port->act = ((ps2port->act+1) & BUFFER_SIZE);
 271             rxflags =   ((status & GSC_STAT_TERR) ? SERIO_TIMEOUT : 0 ) |
 272                         ((status & GSC_STAT_PERR) ? SERIO_PARITY  : 0 );
 273
 274             serio_interrupt(ps2port->port, data, rxflags, regs);
 275
 276           } /* while() */
 277
 278         } /* list_for_each_entry */
 279
 280         return IRQ_HANDLED;
 281 }
 282
 283
 284 /*
 285  * gscps2_write() - send a byte out through the aux interface.
 286  */
 287
 288 static int gscps2_write(struct serio *port, unsigned char data)
 289 {
 290         struct gscps2port *ps2port = port->port_data;
 291
 292         if (!gscps2_writeb_output(ps2port, data)) {
 293                 printk(KERN_DEBUG PFX "sending byte %#x failed.\n", data);
 294                 return -1;
 295         }
 296         return 0;
 297 }
 298
 299 /*
 300  * gscps2_open() is called when a port is opened by the higher layer.
 301  * It resets and enables the port.
 302  */
 303
 304 static int gscps2_open(struct serio *port)
 305 {
 306         struct gscps2port *ps2port = port->port_data;
 307
 308         gscps2_reset(ps2port);
 309
 310         gscps2_interrupt(0, NULL, NULL);
 311
 312         return 0;
 313 }
 314
 315 /*
 316  * gscps2_close() disables the port
 317  */
 318
 319 static void gscps2_close(struct serio *port)
 320 {
 321         struct gscps2port *ps2port = port->port_data;
 322         gscps2_enable(ps2port, DISABLE);
 323 }
 324
 325 /**
 326  * gscps2_probe() - Probes PS2 devices
 327  * @return: success/error report
 328  */
 329
 330 static int __init gscps2_probe(struct parisc_device *dev)
 331 {
 332         struct gscps2port *ps2port;
 333         struct serio *serio;
 334         unsigned long hpa = dev->hpa;
 335         int ret;
 336
 337         if (!dev->irq)
 338                 return -ENODEV;
 339
 340         /* Offset for DINO PS/2. Works with LASI even */
 341         if (dev->id.sversion == 0x96)
 342                 hpa += GSC_DINO_OFFSET;
 343
 344         ps2port = kmalloc(sizeof(struct gscps2port), GFP_KERNEL);
 345         serio = kmalloc(sizeof(struct serio), GFP_KERNEL);
 346         if (!ps2port || !serio) {
 347                 ret = -ENOMEM;
 348                 goto fail_nomem;
 349         }
 350
 351         dev_set_drvdata(&dev->dev, ps2port);
 352
 353         memset(ps2port, 0, sizeof(struct gscps2port));
 354         memset(serio, 0, sizeof(struct serio));
 355         ps2port->port = serio;
 356         ps2port->padev = dev;
 357         ps2port->addr = ioremap(hpa, GSC_STATUS + 4);
 358         spin_lock_init(&ps2port->lock);
 359
 360         gscps2_reset(ps2port);
 361         ps2port->id = readb(ps2port->addr + GSC_ID) & 0x0f;
 362
 363         snprintf(serio->name, sizeof(serio->name), "GSC PS/2 %s",
 364                  (ps2port->id == GSC_ID_KEYBOARD) ? "keyboard" : "mouse");
 365         strlcpy(serio->phys, dev->dev.bus_id, sizeof(serio->phys));
 366         serio->id.type          = SERIO_8042;
 367         serio->write            = gscps2_write;
 368         serio->open             = gscps2_open;
 369         serio->close            = gscps2_close;
 370         serio->port_data        = ps2port;
 371         serio->dev.parent       = &dev->dev;
 372
 373         list_add_tail(&ps2port->node, &ps2port_list);
 374
 375         ret = -EBUSY;
 376         if (request_irq(dev->irq, gscps2_interrupt, SA_SHIRQ, ps2port->port->name, ps2port))
 377                 goto fail_miserably;
 378
 379         if (ps2port->id != GSC_ID_KEYBOARD && ps2port->id != GSC_ID_MOUSE) {
 380                 printk(KERN_WARNING PFX "Unsupported PS/2 port at 0x%08lx (id=%d) ignored\n",
 381                                 hpa, ps2port->id);
 382                 ret = -ENODEV;
 383                 goto fail;
 384         }
 385
 386 #if 0
 387         if (!request_mem_region(hpa, GSC_STATUS + 4, ps2port->port.name))
 388                 goto fail;
 389 #endif
 390
 391         printk(KERN_INFO "serio: %s port at 0x%p irq %d @ %s\n",
 392                 ps2port->port->name,
 393                 ps2port->addr,
 394                 ps2port->padev->irq,
 395                 ps2port->port->phys);
 396
 397         serio_register_port(ps2port->port);
 398
 399         return 0;
 400
 401 fail:
 402         free_irq(dev->irq, ps2port);
 403
 404 fail_miserably:
 405         list_del(&ps2port->node);
 406         iounmap(ps2port->addr);
 407         release_mem_region(dev->hpa, GSC_STATUS + 4);
 408
 409 fail_nomem:
 410         kfree(ps2port);
 411         kfree(serio);
 412         return ret;
 413 }
 414
 415 /**
 416  * gscps2_remove() - Removes PS2 devices
 417  * @return: success/error report
 418  */
 419
 420 static int __devexit gscps2_remove(struct parisc_device *dev)
 421 {
 422         struct gscps2port *ps2port = dev_get_drvdata(&dev->dev);
 423
 424         serio_unregister_port(ps2port->port);
 425         free_irq(dev->irq, ps2port);
 426         gscps2_flush(ps2port);
 427         list_del(&ps2port->node);
 428         iounmap(ps2port->addr);
 429 #if 0
 430         release_mem_region(dev->hpa, GSC_STATUS + 4);
 431 #endif
 432         dev_set_drvdata(&dev->dev, NULL);
 433         kfree(ps2port);
 434         return 0;
 435 }
 436
 437
 438 static struct parisc_device_id gscps2_device_tbl[] = {
 439         { HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x00084 }, /* LASI PS/2 */
 440 #ifdef DINO_TESTED
 441         { HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x00096 }, /* DINO PS/2 */
 442 #endif
 443         { 0, }  /* 0 terminated list */
 444 };
 445
 446 static struct parisc_driver parisc_ps2_driver = {
 447         .name           = "GSC PS2",
 448         .id_table       = gscps2_device_tbl,
 449         .probe          = gscps2_probe,
 450         .remove         = gscps2_remove,
 451 };
 452
 453 static int __init gscps2_init(void)
 454 {
 455         register_parisc_driver(&parisc_ps2_driver);
 456         return 0;
 457 }
 458
 459 static void __exit gscps2_exit(void)
 460 {
 461         unregister_parisc_driver(&parisc_ps2_driver);
 462 }
 463
 464
 465 module_init(gscps2_init);
 466 module_exit(gscps2_exit);
 467