The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/i386/isa/spic.c

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    1 /*-
    2  * Copyright (c) 2000  Nick Sayer
    3  * All rights reserved.
    4  *
    5  * Redistribution and use in source and binary forms, with or without
    6  * modification, are permitted provided that the following conditions
    7  * are met:
    8  * 1. Redistributions of source code must retain the above copyright
    9  *    notice, this list of conditions and the following disclaimer.
   10  * 2. Redistributions in binary form must reproduce the above copyright
   11  *    notice, this list of conditions and the following disclaimer in the
   12  *    documentation and/or other materials provided with the distribution.
   13  *
   14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   24  * SUCH DAMAGE.
   25  */
   26 
   27 /* spic -- the Sony Programmable I/O Controller
   28  *
   29  * This device exists on most recent Sony laptops. It is the means by which
   30  * you can watch the Jog Dial and some other functions.
   31  *
   32  * At the moment, this driver merely tries to turn the jog dial into a
   33  * device that moused can park on, with the intent of supplying a Z axis
   34  * and mouse button out of the jog dial. I suspect that this device will
   35  * end up having to support at least 2 different minor devices: One to be
   36  * the jog wheel device for moused to camp out on and the other to perform
   37  * all of the other miscellaneous functions of this device. But for now,
   38  * the jog wheel is all you get.
   39  *
   40  * At the moment, the data sent back by the device is rather primitive.
   41  * It sends a single character per event:
   42  * u = up, d = down -- that's the jog button
   43  * l = left, r = right -- that's the dial.
   44  * "left" and "right" are rather capricious. They actually represent
   45  * ccw and cw, respectively
   46  *
   47  * What documentation exists is thanks to Andrew Tridge, and his page at
   48  * http://samba.org/picturebook/ Special thanks also to Ian Dowse, who
   49  * also provided sample code upon which this driver was based.
   50  */
   51 
   52 #include <sys/cdefs.h>
   53 __FBSDID("$FreeBSD: stable/11/sys/i386/isa/spic.c 320921 2017-07-12 20:10:53Z jhb $");
   54 
   55 #include <sys/param.h>
   56 #include <sys/systm.h>
   57 #include <sys/kernel.h>
   58 #include <sys/module.h>
   59 #include <sys/bus.h>
   60 #include <machine/bus.h>
   61 #include <sys/rman.h>
   62 #include <machine/resource.h>
   63 #include <isa/isavar.h>
   64 #include <sys/poll.h>
   65 #include <machine/pci_cfgreg.h>
   66 #include <sys/tty.h>
   67 #include <sys/conf.h>
   68 #include <sys/fcntl.h>
   69 #include <sys/malloc.h>
   70 #include <sys/sysctl.h>
   71 #include <sys/uio.h>
   72 
   73 #include <i386/isa/spicreg.h>
   74 
   75 static int spic_pollrate;
   76 
   77 SYSCTL_INT(_machdep, OID_AUTO, spic_pollrate, CTLFLAG_RW, &spic_pollrate, 0, "")
   78 ;
   79 
   80 devclass_t spic_devclass;
   81 
   82 static d_open_t         spicopen;
   83 static d_close_t        spicclose;
   84 static d_read_t         spicread;
   85 static d_ioctl_t        spicioctl;
   86 static d_poll_t         spicpoll;
   87 
   88 static struct cdevsw spic_cdevsw = {
   89         .d_version =    D_VERSION,
   90         .d_open =       spicopen,
   91         .d_close =      spicclose,
   92         .d_read =       spicread,
   93         .d_ioctl =      spicioctl,
   94         .d_poll =       spicpoll,
   95         .d_name =       "spic",
   96 };
   97 
   98 #define SCBUFLEN 128
   99 
  100 struct spic_softc {
  101         u_int sc_port_addr;
  102         u_char sc_intr;
  103         struct resource *sc_port_res,*sc_intr_res;
  104         int     sc_port_rid,sc_intr_rid;
  105         int sc_opened;
  106         int sc_sleeping;
  107         int sc_buttonlast;
  108         struct callout sc_timeout;
  109         struct mtx sc_lock;
  110         device_t sc_dev;
  111         struct cdev *sc_cdev;
  112         struct selinfo sc_rsel;
  113         u_char sc_buf[SCBUFLEN];
  114         int sc_count;
  115         int sc_model;
  116 };
  117 
  118 static void
  119 write_port1(struct spic_softc *sc, u_char val)
  120 {
  121         DELAY(10);
  122         outb(sc->sc_port_addr, val);
  123 }
  124 
  125 static void
  126 write_port2(struct spic_softc *sc, u_char val)
  127 {
  128         DELAY(10);
  129         outb(sc->sc_port_addr + 4, val);
  130 }
  131 
  132 static u_char
  133 read_port1(struct spic_softc *sc)
  134 {
  135         DELAY(10);
  136         return inb(sc->sc_port_addr);
  137 }
  138 
  139 static u_char
  140 read_port2(struct spic_softc *sc)
  141 {
  142         DELAY(10);
  143         return inb(sc->sc_port_addr + 4);
  144 }
  145 
  146 static u_char
  147 read_port_cst(struct spic_softc *sc)
  148 {
  149         DELAY(10);
  150         return inb(SPIC_CST_IOPORT);
  151 }
  152 
  153 static void
  154 busy_wait(struct spic_softc *sc)
  155 {
  156         int i=0;
  157 
  158         while(read_port2(sc) & 2) {
  159                 DELAY(10);
  160                 if (i++>10000) {
  161                         printf("spic busy wait abort\n");
  162                         return;
  163                 }
  164         }
  165 }
  166 
  167 static void
  168 busy_wait_cst(struct spic_softc *sc, int mask)
  169 {
  170         int i=0;
  171 
  172         while(read_port_cst(sc) & mask) {
  173                 DELAY(10);
  174                 if (i++>10000) {
  175                         printf("spic busy wait abort\n");
  176                         return;
  177                 }
  178         }
  179 }
  180 
  181 static u_char
  182 spic_call1(struct spic_softc *sc, u_char dev) {
  183         busy_wait(sc);
  184         write_port2(sc, dev);
  185         read_port2(sc);
  186         return read_port1(sc);
  187 }
  188 
  189 static u_char
  190 spic_call2(struct spic_softc *sc, u_char dev, u_char fn)
  191 {
  192         busy_wait(sc);
  193         write_port2(sc, dev);
  194         busy_wait(sc);
  195         write_port1(sc, fn);
  196         return read_port1(sc);
  197 }
  198 
  199 static void
  200 spic_ecrset(struct spic_softc *sc, u_int16_t addr, u_int16_t value)
  201 {
  202         busy_wait_cst(sc, 3);
  203         outb(SPIC_CST_IOPORT, 0x81);
  204         busy_wait_cst(sc, 2);
  205         outb(SPIC_DATA_IOPORT, addr);
  206         busy_wait_cst(sc, 2);
  207         outb(SPIC_DATA_IOPORT, value);
  208         busy_wait_cst(sc, 2);
  209 }
  210 
  211 static void
  212 spic_type2_srs(struct spic_softc *sc)
  213 {
  214         spic_ecrset(sc, SPIC_SHIB, (sc->sc_port_addr & 0xFF00) >> 8);
  215         spic_ecrset(sc, SPIC_SLOB,  sc->sc_port_addr & 0x00FF);
  216         spic_ecrset(sc, SPIC_SIRQ,  0x00); /* using polling mode (IRQ=0)*/
  217         DELAY(10);
  218 }
  219 
  220 static int
  221 spic_probe(device_t dev)
  222 {
  223         struct spic_softc *sc;
  224         u_char t, spic_irq;
  225 
  226         sc = device_get_softc(dev);
  227 
  228         /*
  229          * We can only have 1 of these. Attempting to probe for a unit 1
  230          * will destroy the work we did for unit 0
  231          */
  232         if (device_get_unit(dev))
  233                 return ENXIO;
  234 
  235         bzero(sc, sizeof(struct spic_softc));
  236 
  237         if (!(sc->sc_port_res = bus_alloc_resource_anywhere(dev, SYS_RES_IOPORT,
  238                 &sc->sc_port_rid, 5, RF_ACTIVE))) {
  239                 device_printf(dev,"Couldn't map I/O\n");
  240                 return ENXIO;
  241         }
  242         sc->sc_port_addr = (u_short)rman_get_start(sc->sc_port_res);
  243 
  244 #ifdef notyet
  245         if (!(sc->sc_intr_res = bus_alloc_resource_any(dev, SYS_RES_IRQ,
  246                 &sc->sc_intr_rid, RF_ACTIVE))) {
  247                 device_printf(dev,"Couldn't map IRQ\n");
  248                 bus_release_resource(dev, SYS_RES_IOPORT,
  249                         sc->sc_port_rid, sc->sc_port_res);
  250                 return ENXIO;
  251         }
  252         sc->sc_intr = (u_short)rman_get_start(sc->sc_intr_res);
  253 
  254         switch (sc->sc_intr) {
  255                 case 0: spic_irq = 3; break;
  256                 case 5: spic_irq = 0; break;
  257                 case 0xa: spic_irq = 1; break;
  258                 case 0xb: spic_irq = 2; break;
  259                 default: device_printf(dev,"Invalid IRQ\n");
  260                         bus_release_resource(dev, SYS_RES_IOPORT,
  261                                 sc->sc_port_rid, sc->sc_port_res);
  262                         bus_release_resource(dev, SYS_RES_IRQ,
  263                                 sc->sc_intr_rid, sc->sc_intr_res);
  264                         return ENXIO;
  265         }
  266 #else
  267         spic_irq = 3;
  268 #endif
  269 
  270 #if 0
  271         if (sc->sc_port_addr != 0x10A0) {
  272                 bus_release_resource(dev, SYS_RES_IOPORT,
  273                         sc->sc_port_rid, sc->sc_port_res);
  274                 bus_release_resource(dev, SYS_RES_IRQ,
  275                         sc->sc_intr_rid, sc->sc_intr_res);
  276                 return ENXIO;
  277         }
  278 #endif
  279 
  280         /* PIIX4 chipset at least? */
  281         if (pci_cfgregread(PIIX4_BUS, PIIX4_SLOT, PIIX4_FUNC, 0, 4) ==
  282                 PIIX4_DEVID) {
  283                 sc->sc_model = SPIC_DEVICE_MODEL_TYPE1;
  284         } else {
  285                 /* For newer VAIOs (R505, SRX7, ...) */
  286                 sc->sc_model = SPIC_DEVICE_MODEL_TYPE2;
  287         }
  288 
  289         /*
  290          * This is an ugly hack. It is necessary until ACPI works correctly.
  291          *
  292          * The SPIC consists of 2 registers. They are mapped onto I/O by the
  293          * PIIX4's General Device 10 function. There is also an interrupt
  294          * control port at a somewhat magic location, but this first pass is
  295          * polled.
  296          *
  297          * So the first thing we need to do is map the G10 space in.
  298          *
  299          */
  300 
  301         /* Enable ACPI mode to get Fn key events */
  302         /* XXX This may slow down your VAIO if ACPI is not supported in the kernel.
  303         outb(0xb2, 0xf0);
  304         */
  305 
  306         device_printf(dev,"device model type = %d\n", sc->sc_model);
  307         
  308         if(sc->sc_model == SPIC_DEVICE_MODEL_TYPE1) {
  309                 pci_cfgregwrite(PIIX4_BUS, PIIX4_SLOT, PIIX4_FUNC, G10A,
  310                                 sc->sc_port_addr, 2);
  311                 t = pci_cfgregread(PIIX4_BUS, PIIX4_SLOT, PIIX4_FUNC, G10L, 1);
  312                 t &= 0xf0;
  313                 t |= 4;
  314                 pci_cfgregwrite(PIIX4_BUS, PIIX4_SLOT, PIIX4_FUNC, G10L, t, 1);
  315                 outw(SPIC_IRQ_PORT, (inw(SPIC_IRQ_PORT) & ~(0x3 << SPIC_IRQ_SHIFT)) | (spic_irq << SPIC_IRQ_SHIFT));
  316                 t = pci_cfgregread(PIIX4_BUS, PIIX4_SLOT, PIIX4_FUNC, G10L, 1);
  317                 t &= 0x1f;
  318                 t |= 0xc0;
  319                 pci_cfgregwrite(PIIX4_BUS, PIIX4_SLOT, PIIX4_FUNC, G10L, t, 1);
  320         } else {
  321                 spic_type2_srs(sc);
  322         }
  323 
  324         /*
  325          * XXX: Should try and see if there's anything actually there.
  326          */
  327 
  328         device_set_desc(dev, "Sony Programmable I/O Controller");
  329 
  330         return 0;
  331 }
  332 
  333 static int
  334 spic_attach(device_t dev)
  335 {
  336         struct spic_softc *sc;
  337 
  338         sc = device_get_softc(dev);
  339 
  340         sc->sc_dev = dev;
  341         mtx_init(&sc->sc_lock, "spic", NULL, MTX_DEF);
  342         callout_init_mtx(&sc->sc_timeout, &sc->sc_lock, 0);
  343         
  344         spic_pollrate = (hz/50); /* Every 50th of a second */
  345 
  346         spic_call1(sc, 0x82);
  347         spic_call2(sc, 0x81, 0xff);
  348         spic_call1(sc, 0x92);
  349 
  350         /* There can be only one */
  351         sc->sc_cdev = make_dev(&spic_cdevsw, 0, 0, 0, 0600, "jogdial");
  352         sc->sc_cdev->si_drv1 = sc;
  353         device_printf(dev,
  354             "WARNING: This driver is deprecated and will be removed.\n");
  355 
  356         return 0;
  357 }
  358 
  359 static void
  360 spictimeout(void *arg)
  361 {
  362         struct spic_softc *sc = arg;
  363         u_char b, event, param;
  364         int j;
  365 
  366         mtx_assert(&sc->sc_lock, MA_OWNED);
  367         if (!sc->sc_opened) {
  368                 device_printf(sc->sc_dev, "timeout called while closed!\n");
  369                 return;
  370         }
  371 
  372         event = read_port2(sc);
  373         param = read_port1(sc);
  374 
  375         if ((event != 4) && (!(event & 0x1)))
  376                 switch(event) {
  377                         case 0x10: /* jog wheel event (type1) */
  378                                 if (sc->sc_model == SPIC_DEVICE_MODEL_TYPE1) {
  379                                         b = !!(param & 0x40);
  380                                         if (b != sc->sc_buttonlast) {
  381                                                 sc->sc_buttonlast = b;
  382                                                 sc->sc_buf[sc->sc_count++] =
  383                                                         b?'d':'u';
  384                                         }
  385                                         j = (param & 0xf) | ((param & 0x10)? ~0xf:0);
  386                                         if (j<0)
  387                                                 while(j++!=0) {
  388                                                         sc->sc_buf[sc->sc_count++] =
  389                                                                 'l';
  390                                                 }
  391                                         else if (j>0)
  392                                                 while(j--!=0) {
  393                                                         sc->sc_buf[sc->sc_count++] =
  394                                                                 'r';
  395                                                 }
  396                                 }
  397                                 break;
  398                         case 0x08: /* jog wheel event (type2) */
  399                         case 0x00: 
  400                                 /* SPIC_DEVICE_MODEL_TYPE2 returns jog wheel event=0x00 */
  401                                 if (sc->sc_model == SPIC_DEVICE_MODEL_TYPE2) {
  402                                         b = !!(param & 0x40);
  403                                         if (b != sc->sc_buttonlast) {
  404                                                 sc->sc_buttonlast = b;
  405                                                 sc->sc_buf[sc->sc_count++] =
  406                                                         b?'d':'u';
  407                                         }
  408                                         j = (param & 0xf) | ((param & 0x10)? ~0xf:0);
  409                                         if (j<0)
  410                                                 while(j++!=0) {
  411                                                         sc->sc_buf[sc->sc_count++] =
  412                                                                 'l';
  413                                                 }
  414                                         else if (j>0)
  415                                                 while(j--!=0) {
  416                                                         sc->sc_buf[sc->sc_count++] =
  417                                                                 'r';
  418                                                 }
  419                                 }
  420                                 break;
  421                         case 0x60: /* Capture button */
  422                                 printf("Capture button event: %x\n",param);
  423                                 break;
  424                         case 0x30: /* Lid switch */
  425                                 printf("Lid switch event: %x\n",param);
  426                                 break;
  427                         case 0x0c: /* We must ignore these type of event for C1VP... */
  428                         case 0x70: /* Closing/Opening the lid on C1VP */
  429                                 break;
  430                         default:
  431                                 printf("Unknown event: event %02x param %02x\n", event, param);
  432                                 break;
  433                 }
  434         else {
  435                 /* No event. Wait some more */
  436                 callout_reset(&sc->sc_timeout, spic_pollrate, spictimeout, sc);
  437                 return;
  438         }
  439 
  440         if (sc->sc_count) {
  441                 if (sc->sc_sleeping) {
  442                         sc->sc_sleeping = 0;
  443                         wakeup( sc);
  444                 }
  445                 selwakeuppri(&sc->sc_rsel, PZERO);
  446         }
  447         spic_call2(sc, 0x81, 0xff); /* Clear event */
  448 
  449         callout_reset(&sc->sc_timeout, spic_pollrate, spictimeout, sc);
  450 }
  451 
  452 static int
  453 spicopen(struct cdev *dev, int flag, int fmt, struct thread *td)
  454 {
  455         struct spic_softc *sc;
  456 
  457         sc = dev->si_drv1;
  458 
  459         mtx_lock(&sc->sc_lock);
  460         if (sc->sc_opened) {
  461                 mtx_unlock(&sc->sc_lock);
  462                 return (EBUSY);
  463         }
  464 
  465         sc->sc_opened++;
  466         sc->sc_count=0;
  467 
  468         /* Start the polling */
  469         callout_reset(&sc->sc_timeout, spic_pollrate, spictimeout, sc);
  470         mtx_unlock(&sc->sc_lock);
  471         return (0);
  472 }
  473 
  474 static int
  475 spicclose(struct cdev *dev, int flag, int fmt, struct thread *td)
  476 {
  477         struct spic_softc *sc;
  478 
  479         sc = dev->si_drv1;
  480         mtx_lock(&sc->sc_lock);
  481 
  482         /* Stop polling */
  483         callout_stop(&sc->sc_timeout);
  484         sc->sc_opened = 0;
  485         mtx_unlock(&sc->sc_lock);
  486         return 0;
  487 }
  488 
  489 static int
  490 spicread(struct cdev *dev, struct uio *uio, int flag)
  491 {
  492         struct spic_softc *sc;
  493         int l, error;
  494         u_char buf[SCBUFLEN];
  495 
  496         sc = dev->si_drv1;
  497 
  498         if (uio->uio_resid <= 0) /* What kind of a read is this?! */
  499                 return (0);
  500 
  501         mtx_lock(&sc->sc_lock);
  502         while (!(sc->sc_count)) {
  503                 sc->sc_sleeping=1;
  504                 error = mtx_sleep(sc, &sc->sc_lock, PZERO | PCATCH, "jogrea", 0);
  505                 sc->sc_sleeping=0;
  506                 if (error) {
  507                         mtx_unlock(&sc->sc_lock);
  508                         return (error);
  509                 }
  510         }
  511 
  512         l = min(uio->uio_resid, sc->sc_count);
  513         bcopy(sc->sc_buf, buf, l);
  514         sc->sc_count -= l;
  515         bcopy(sc->sc_buf + l, sc->sc_buf, l);
  516         mtx_unlock(&sc->sc_lock);
  517         return (uiomove(buf, l, uio));
  518 }
  519 
  520 static int
  521 spicioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td)
  522 {
  523         struct spic_softc *sc;
  524 
  525         sc = dev->si_drv1;
  526 
  527         return (EIO);
  528 }
  529 
  530 static int
  531 spicpoll(struct cdev *dev, int events, struct thread *td)
  532 {
  533         struct spic_softc *sc;
  534         int revents = 0;
  535 
  536         sc = dev->si_drv1;
  537         mtx_lock(&sc->sc_lock);
  538         if (events & (POLLIN | POLLRDNORM)) {
  539                 if (sc->sc_count)
  540                         revents |= events & (POLLIN | POLLRDNORM);
  541                 else
  542                         selrecord(td, &sc->sc_rsel); /* Who shall we wake? */
  543         }
  544         mtx_unlock(&sc->sc_lock);
  545 
  546         return (revents);
  547 }
  548 
  549 
  550 static device_method_t spic_methods[] = {
  551         DEVMETHOD(device_probe,         spic_probe),
  552         DEVMETHOD(device_attach,        spic_attach),
  553 
  554         { 0, 0 }
  555 };
  556 
  557 static driver_t spic_driver = {
  558         "spic",
  559         spic_methods,
  560         sizeof(struct spic_softc),
  561 };
  562 
  563 DRIVER_MODULE(spic, isa, spic_driver, spic_devclass, 0, 0);
  564 

Cache object: 182dd204afdf3fb705ae59621090980a


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