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/slab.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);
  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 success, 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);
 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
 216 static LIST_HEAD(ps2port_list);
 217
 218 /**
 219  * gscps2_interrupt() - Interruption service routine
 220  *
 221  * This function reads received PS/2 bytes and processes them on
 222  * all interfaces.
 223  * The problematic part here is, that the keyboard and mouse PS/2 port
 224  * share the same interrupt and it's not possible to send data if any
 225  * one of them holds input data. To solve this problem we try to receive
 226  * the data as fast as possible and handle the reporting to the upper layer
 227  * later.
 228  */
 229
 230 static irqreturn_t gscps2_interrupt(int irq, void *dev)
 231 {
 232         struct gscps2port *ps2port;
 233
 234         list_for_each_entry(ps2port, &ps2port_list, node) {
 235
 236           unsigned long flags;
 237           spin_lock_irqsave(&ps2port->lock, flags);
 238
 239           while ( (ps2port->buffer[ps2port->append].str =
 240                    gscps2_readb_status(ps2port->addr)) & GSC_STAT_RBNE ) {
 241                 ps2port->buffer[ps2port->append].data =
 242                                 gscps2_readb_input(ps2port->addr);
 243                 ps2port->append = ((ps2port->append+1) & BUFFER_SIZE);
 244           }
 245
 246           spin_unlock_irqrestore(&ps2port->lock, flags);
 247
 248         } /* list_for_each_entry */
 249
 250         /* all data was read from the ports - now report the data to upper layer */
 251
 252         list_for_each_entry(ps2port, &ps2port_list, node) {
 253
 254           while (ps2port->act != ps2port->append) {
 255
 256             unsigned int rxflags;
 257             u8 data, status;
 258
 259             /* Did new data arrived while we read existing data ?
 260                If yes, exit now and let the new irq handler start over again */
 261             if (gscps2_readb_status(ps2port->addr) & GSC_STAT_CMPINTR)
 262                 return IRQ_HANDLED;
 263
 264             status = ps2port->buffer[ps2port->act].str;
 265             data   = ps2port->buffer[ps2port->act].data;
 266
 267             ps2port->act = ((ps2port->act+1) & BUFFER_SIZE);
 268             rxflags =   ((status & GSC_STAT_TERR) ? SERIO_TIMEOUT : 0 ) |
 269                         ((status & GSC_STAT_PERR) ? SERIO_PARITY  : 0 );
 270
 271             serio_interrupt(ps2port->port, data, rxflags);
 272
 273           } /* while() */
 274
 275         } /* list_for_each_entry */
 276
 277         return IRQ_HANDLED;
 278 }
 279
 280
 281 /*
 282  * gscps2_write() - send a byte out through the aux interface.
 283  */
 284
 285 static int gscps2_write(struct serio *port, unsigned char data)
 286 {
 287         struct gscps2port *ps2port = port->port_data;
 288
 289         if (!gscps2_writeb_output(ps2port, data)) {
 290                 printk(KERN_DEBUG PFX "sending byte %#x failed.\n", data);
 291                 return -1;
 292         }
 293         return 0;
 294 }
 295
 296 /*
 297  * gscps2_open() is called when a port is opened by the higher layer.
 298  * It resets and enables the port.
 299  */
 300
 301 static int gscps2_open(struct serio *port)
 302 {
 303         struct gscps2port *ps2port = port->port_data;
 304
 305         gscps2_reset(ps2port);
 306
 307         /* enable it */
 308         gscps2_enable(ps2port, ENABLE);
 309
 310         gscps2_interrupt(0, 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 gscps2_probe(struct parisc_device *dev)
 331 {
 332         struct gscps2port *ps2port;
 333         struct serio *serio;
 334         unsigned long hpa = dev->hpa.start;
 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 = kzalloc(sizeof(struct gscps2port), GFP_KERNEL);
 345         serio = kzalloc(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         ps2port->port = serio;
 354         ps2port->padev = dev;
 355         ps2port->addr = ioremap_nocache(hpa, GSC_STATUS + 4);
 356         spin_lock_init(&ps2port->lock);
 357
 358         gscps2_reset(ps2port);
 359         ps2port->id = readb(ps2port->addr + GSC_ID) & 0x0f;
 360
 361         snprintf(serio->name, sizeof(serio->name), "gsc-ps2-%s",
 362                  (ps2port->id == GSC_ID_KEYBOARD) ? "keyboard" : "mouse");
 363         strlcpy(serio->phys, dev_name(&dev->dev), sizeof(serio->phys));
 364         serio->id.type          = SERIO_8042;
 365         serio->write            = gscps2_write;
 366         serio->open             = gscps2_open;
 367         serio->close            = gscps2_close;
 368         serio->port_data        = ps2port;
 369         serio->dev.parent       = &dev->dev;
 370
 371         ret = -EBUSY;
 372         if (request_irq(dev->irq, gscps2_interrupt, IRQF_SHARED, ps2port->port->name, ps2port))
 373                 goto fail_miserably;
 374
 375         if (ps2port->id != GSC_ID_KEYBOARD && ps2port->id != GSC_ID_MOUSE) {
 376                 printk(KERN_WARNING PFX "Unsupported PS/2 port at 0x%08lx (id=%d) ignored\n",
 377                                 hpa, ps2port->id);
 378                 ret = -ENODEV;
 379                 goto fail;
 380         }
 381
 382 #if 0
 383         if (!request_mem_region(hpa, GSC_STATUS + 4, ps2port->port.name))
 384                 goto fail;
 385 #endif
 386
 387         printk(KERN_INFO "serio: %s port at 0x%p irq %d @ %s\n",
 388                 ps2port->port->name,
 389                 ps2port->addr,
 390                 ps2port->padev->irq,
 391                 ps2port->port->phys);
 392
 393         serio_register_port(ps2port->port);
 394
 395         list_add_tail(&ps2port->node, &ps2port_list);
 396
 397         return 0;
 398
 399 fail:
 400         free_irq(dev->irq, ps2port);
 401
 402 fail_miserably:
 403         iounmap(ps2port->addr);
 404         release_mem_region(dev->hpa.start, GSC_STATUS + 4);
 405
 406 fail_nomem:
 407         kfree(ps2port);
 408         kfree(serio);
 409         return ret;
 410 }
 411
 412 /**
 413  * gscps2_remove() - Removes PS2 devices
 414  * @return: success/error report
 415  */
 416
 417 static int gscps2_remove(struct parisc_device *dev)
 418 {
 419         struct gscps2port *ps2port = dev_get_drvdata(&dev->dev);
 420
 421         serio_unregister_port(ps2port->port);
 422         free_irq(dev->irq, ps2port);
 423         gscps2_flush(ps2port);
 424         list_del(&ps2port->node);
 425         iounmap(ps2port->addr);
 426 #if 0
 427         release_mem_region(dev->hpa, GSC_STATUS + 4);
 428 #endif
 429         dev_set_drvdata(&dev->dev, NULL);
 430         kfree(ps2port);
 431         return 0;
 432 }
 433
 434
 435 static struct parisc_device_id gscps2_device_tbl[] = {
 436         { HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x00084 }, /* LASI PS/2 */
 437 #ifdef DINO_TESTED
 438         { HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x00096 }, /* DINO PS/2 */
 439 #endif
 440         { 0, }  /* 0 terminated list */
 441 };
 442
 443 static struct parisc_driver parisc_ps2_driver = {
 444         .name           = "gsc_ps2",
 445         .id_table       = gscps2_device_tbl,
 446         .probe          = gscps2_probe,
 447         .remove         = gscps2_remove,
 448 };
 449
 450 static int __init gscps2_init(void)
 451 {
 452         register_parisc_driver(&parisc_ps2_driver);
 453         return 0;
 454 }
 455
 456 static void __exit gscps2_exit(void)
 457 {
 458         unregister_parisc_driver(&parisc_ps2_driver);
 459 }
 460
 461
 462 module_init(gscps2_init);
 463 module_exit(gscps2_exit);
 464