The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/arm/mv/gpio.c

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    1 /*-
    2  * Copyright (c) 2006 Benno Rice.
    3  * Copyright (C) 2008 MARVELL INTERNATIONAL LTD.
    4  * All rights reserved.
    5  *
    6  * Adapted and extended for Marvell SoCs by Semihalf.
    7  *
    8  * Redistribution and use in source and binary forms, with or without
    9  * modification, are permitted provided that the following conditions
   10  * are met:
   11  * 1. Redistributions of source code must retain the above copyright
   12  *    notice, this list of conditions and the following disclaimer.
   13  * 2. Redistributions in binary form must reproduce the above copyright
   14  *    notice, this list of conditions and the following disclaimer in the
   15  *    documentation and/or other materials provided with the distribution.
   16  *
   17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
   18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
   20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
   21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
   26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   27  *
   28  * from: FreeBSD: //depot/projects/arm/src/sys/arm/xscale/pxa2x0/pxa2x0_gpio.c, rev 1
   29  */
   30 
   31 #include <sys/cdefs.h>
   32 __FBSDID("$FreeBSD: releng/11.2/sys/arm/mv/gpio.c 331722 2018-03-29 02:50:57Z eadler $");
   33 
   34 #include <sys/param.h>
   35 #include <sys/systm.h>
   36 #include <sys/bus.h>
   37 #include <sys/kernel.h>
   38 #include <sys/lock.h>
   39 #include <sys/interrupt.h>
   40 #include <sys/module.h>
   41 #include <sys/malloc.h>
   42 #include <sys/mutex.h>
   43 #include <sys/rman.h>
   44 #include <sys/queue.h>
   45 #include <sys/timetc.h>
   46 #include <machine/bus.h>
   47 #include <machine/intr.h>
   48 
   49 #include <dev/fdt/fdt_common.h>
   50 #include <dev/ofw/ofw_bus.h>
   51 #include <dev/ofw/ofw_bus_subr.h>
   52 
   53 #include <arm/mv/mvvar.h>
   54 #include <arm/mv/mvreg.h>
   55 
   56 #define GPIO_MAX_INTR_COUNT     8
   57 #define GPIO_PINS_PER_REG       32
   58 
   59 struct mv_gpio_softc {
   60         struct resource *       res[GPIO_MAX_INTR_COUNT + 1];
   61         void                    *ih_cookie[GPIO_MAX_INTR_COUNT];
   62         bus_space_tag_t         bst;
   63         bus_space_handle_t      bsh;
   64         uint8_t                 pin_num;        /* number of GPIO pins */
   65         uint8_t                 irq_num;        /* number of real IRQs occupied by GPIO controller */
   66 };
   67 
   68 extern struct resource_spec mv_gpio_res[];
   69 
   70 static struct mv_gpio_softc *mv_gpio_softc = NULL;
   71 static uint32_t gpio_setup[MV_GPIO_MAX_NPINS];
   72 
   73 static int      mv_gpio_probe(device_t);
   74 static int      mv_gpio_attach(device_t);
   75 static int      mv_gpio_intr(void *);
   76 static int      mv_gpio_init(void);
   77 
   78 static void     mv_gpio_intr_handler(int pin);
   79 static uint32_t mv_gpio_reg_read(uint32_t reg);
   80 static void     mv_gpio_reg_write(uint32_t reg, uint32_t val);
   81 static void     mv_gpio_reg_set(uint32_t reg, uint32_t val);
   82 static void     mv_gpio_reg_clear(uint32_t reg, uint32_t val);
   83 
   84 static void     mv_gpio_blink(uint32_t pin, uint8_t enable);
   85 static void     mv_gpio_polarity(uint32_t pin, uint8_t enable);
   86 static void     mv_gpio_level(uint32_t pin, uint8_t enable);
   87 static void     mv_gpio_edge(uint32_t pin, uint8_t enable);
   88 static void     mv_gpio_out_en(uint32_t pin, uint8_t enable);
   89 static void     mv_gpio_int_ack(uint32_t pin);
   90 static void     mv_gpio_value_set(uint32_t pin, uint8_t val);
   91 static uint32_t mv_gpio_value_get(uint32_t pin);
   92 
   93 static device_method_t mv_gpio_methods[] = {
   94         DEVMETHOD(device_probe,         mv_gpio_probe),
   95         DEVMETHOD(device_attach,        mv_gpio_attach),
   96         { 0, 0 }
   97 };
   98 
   99 static driver_t mv_gpio_driver = {
  100         "gpio",
  101         mv_gpio_methods,
  102         sizeof(struct mv_gpio_softc),
  103 };
  104 
  105 static devclass_t mv_gpio_devclass;
  106 
  107 DRIVER_MODULE(gpio, simplebus, mv_gpio_driver, mv_gpio_devclass, 0, 0);
  108 
  109 typedef int (*gpios_phandler_t)(phandle_t, pcell_t *, int);
  110 
  111 struct gpio_ctrl_entry {
  112         const char              *compat;
  113         gpios_phandler_t        handler;
  114 };
  115 
  116 static int mv_handle_gpios_prop(phandle_t ctrl, pcell_t *gpios, int len);
  117 int gpio_get_config_from_dt(void);
  118 
  119 struct gpio_ctrl_entry gpio_controllers[] = {
  120         { "mrvl,gpio", &mv_handle_gpios_prop },
  121         { NULL, NULL }
  122 };
  123 
  124 static int
  125 mv_gpio_probe(device_t dev)
  126 {
  127 
  128         if (!ofw_bus_status_okay(dev))
  129                 return (ENXIO);
  130 
  131         if (!ofw_bus_is_compatible(dev, "mrvl,gpio"))
  132                 return (ENXIO);
  133 
  134         device_set_desc(dev, "Marvell Integrated GPIO Controller");
  135         return (0);
  136 }
  137 
  138 static int
  139 mv_gpio_attach(device_t dev)
  140 {
  141         int error, i;
  142         struct mv_gpio_softc *sc;
  143         uint32_t dev_id, rev_id;
  144 
  145         sc = (struct mv_gpio_softc *)device_get_softc(dev);
  146         if (sc == NULL)
  147                 return (ENXIO);
  148 
  149         mv_gpio_softc = sc;
  150 
  151         /* Get chip id and revision */
  152         soc_id(&dev_id, &rev_id);
  153 
  154         if (dev_id == MV_DEV_88F5182 ||
  155             dev_id == MV_DEV_88F5281 ||
  156             dev_id == MV_DEV_MV78100 ||
  157             dev_id == MV_DEV_MV78100_Z0 ) {
  158                 sc->pin_num = 32;
  159                 sc->irq_num = 4;
  160 
  161         } else if (dev_id == MV_DEV_88F6281 ||
  162             dev_id == MV_DEV_88F6282) {
  163                 sc->pin_num = 50;
  164                 sc->irq_num = 7;
  165 
  166         } else {
  167                 device_printf(dev, "unknown chip id=0x%x\n", dev_id);
  168                 return (ENXIO);
  169         }
  170 
  171         error = bus_alloc_resources(dev, mv_gpio_res, sc->res);
  172         if (error) {
  173                 device_printf(dev, "could not allocate resources\n");
  174                 return (ENXIO);
  175         }
  176 
  177         sc->bst = rman_get_bustag(sc->res[0]);
  178         sc->bsh = rman_get_bushandle(sc->res[0]);
  179 
  180         /* Disable and clear all interrupts */
  181         bus_space_write_4(sc->bst, sc->bsh, GPIO_INT_EDGE_MASK, 0);
  182         bus_space_write_4(sc->bst, sc->bsh, GPIO_INT_LEV_MASK, 0);
  183         bus_space_write_4(sc->bst, sc->bsh, GPIO_INT_CAUSE, 0);
  184 
  185         if (sc->pin_num > GPIO_PINS_PER_REG) {
  186                 bus_space_write_4(sc->bst, sc->bsh,
  187                     GPIO_HI_INT_EDGE_MASK, 0);
  188                 bus_space_write_4(sc->bst, sc->bsh,
  189                     GPIO_HI_INT_LEV_MASK, 0);
  190                 bus_space_write_4(sc->bst, sc->bsh,
  191                     GPIO_HI_INT_CAUSE, 0);
  192         }
  193 
  194         for (i = 0; i < sc->irq_num; i++) {
  195                 if (bus_setup_intr(dev, sc->res[1 + i],
  196                     INTR_TYPE_MISC, mv_gpio_intr, NULL,
  197                     sc, &sc->ih_cookie[i]) != 0) {
  198                         bus_release_resources(dev, mv_gpio_res, sc->res);
  199                         device_printf(dev, "could not set up intr %d\n", i);
  200                         return (ENXIO);
  201                 }
  202         }
  203 
  204         return (mv_gpio_init());
  205 }
  206 
  207 static int
  208 mv_gpio_intr(void *arg)
  209 {
  210         uint32_t int_cause, gpio_val;
  211         uint32_t int_cause_hi, gpio_val_hi = 0;
  212         int i;
  213 
  214         int_cause = mv_gpio_reg_read(GPIO_INT_CAUSE);
  215         gpio_val = mv_gpio_reg_read(GPIO_DATA_IN);
  216         gpio_val &= int_cause;
  217         if (mv_gpio_softc->pin_num > GPIO_PINS_PER_REG) {
  218                 int_cause_hi = mv_gpio_reg_read(GPIO_HI_INT_CAUSE);
  219                 gpio_val_hi = mv_gpio_reg_read(GPIO_HI_DATA_IN);
  220                 gpio_val_hi &= int_cause_hi;
  221         }
  222 
  223         i = 0;
  224         while (gpio_val != 0) {
  225                 if (gpio_val & 1)
  226                         mv_gpio_intr_handler(i);
  227                 gpio_val >>= 1;
  228                 i++;
  229         }
  230 
  231         if (mv_gpio_softc->pin_num > GPIO_PINS_PER_REG) {
  232                 i = 0;
  233                 while (gpio_val_hi != 0) {
  234                         if (gpio_val_hi & 1)
  235                                 mv_gpio_intr_handler(i + GPIO_PINS_PER_REG);
  236                         gpio_val_hi >>= 1;
  237                         i++;
  238                 }
  239         }
  240 
  241         return (FILTER_HANDLED);
  242 }
  243 
  244 /*
  245  * GPIO interrupt handling
  246  */
  247 
  248 static struct intr_event *gpio_events[MV_GPIO_MAX_NPINS];
  249 
  250 int
  251 mv_gpio_setup_intrhandler(const char *name, driver_filter_t *filt,
  252     void (*hand)(void *), void *arg, int pin, int flags, void **cookiep)
  253 {
  254         struct  intr_event *event;
  255         int     error;
  256 
  257         if (pin < 0 || pin >= mv_gpio_softc->pin_num)
  258                 return (ENXIO);
  259         event = gpio_events[pin];
  260         if (event == NULL) {
  261                 error = intr_event_create(&event, (void *)pin, 0, pin,
  262                     (void (*)(void *))mv_gpio_intr_mask,
  263                     (void (*)(void *))mv_gpio_intr_unmask,
  264                     (void (*)(void *))mv_gpio_int_ack,
  265                     NULL,
  266                     "gpio%d:", pin);
  267                 if (error != 0)
  268                         return (error);
  269                 gpio_events[pin] = event;
  270         }
  271 
  272         intr_event_add_handler(event, name, filt, hand, arg,
  273             intr_priority(flags), flags, cookiep);
  274         return (0);
  275 }
  276 
  277 void
  278 mv_gpio_intr_mask(int pin)
  279 {
  280 
  281         if (pin >= mv_gpio_softc->pin_num)
  282                 return;
  283 
  284         if (gpio_setup[pin] & MV_GPIO_IN_IRQ_EDGE)
  285                 mv_gpio_edge(pin, 0);
  286         else
  287                 mv_gpio_level(pin, 0);
  288 }
  289 
  290 void
  291 mv_gpio_intr_unmask(int pin)
  292 {
  293 
  294         if (pin >= mv_gpio_softc->pin_num)
  295                 return;
  296 
  297         if (gpio_setup[pin] & MV_GPIO_IN_IRQ_EDGE)
  298                 mv_gpio_edge(pin, 1);
  299         else
  300                 mv_gpio_level(pin, 1);
  301 }
  302 
  303 static void
  304 mv_gpio_intr_handler(int pin)
  305 {
  306         struct intr_event *event;
  307 
  308         event = gpio_events[pin];
  309         if (event == NULL || TAILQ_EMPTY(&event->ie_handlers))
  310                 return;
  311 
  312         intr_event_handle(event, NULL);
  313 }
  314 
  315 static int
  316 mv_gpio_configure(uint32_t pin, uint32_t flags)
  317 {
  318 
  319         if (pin >= mv_gpio_softc->pin_num)
  320                 return (EINVAL);
  321 
  322         if (flags & MV_GPIO_OUT_BLINK)
  323                 mv_gpio_blink(pin, 1);
  324         if (flags & MV_GPIO_IN_POL_LOW)
  325                 mv_gpio_polarity(pin, 1);
  326         if (flags & MV_GPIO_IN_IRQ_EDGE)
  327                 mv_gpio_edge(pin, 1);
  328         if (flags & MV_GPIO_IN_IRQ_LEVEL)
  329                 mv_gpio_level(pin, 1);
  330 
  331         gpio_setup[pin] = flags;
  332 
  333         return (0);
  334 }
  335 
  336 void
  337 mv_gpio_out(uint32_t pin, uint8_t val, uint8_t enable)
  338 {
  339 
  340         mv_gpio_value_set(pin, val);
  341         mv_gpio_out_en(pin, enable);
  342 }
  343 
  344 uint8_t
  345 mv_gpio_in(uint32_t pin)
  346 {
  347 
  348         return (mv_gpio_value_get(pin) ? 1 : 0);
  349 }
  350 
  351 static uint32_t
  352 mv_gpio_reg_read(uint32_t reg)
  353 {
  354 
  355         return (bus_space_read_4(mv_gpio_softc->bst,
  356             mv_gpio_softc->bsh, reg));
  357 }
  358 
  359 static void
  360 mv_gpio_reg_write(uint32_t reg, uint32_t val)
  361 {
  362 
  363         bus_space_write_4(mv_gpio_softc->bst,
  364             mv_gpio_softc->bsh, reg, val);
  365 }
  366 
  367 static void
  368 mv_gpio_reg_set(uint32_t reg, uint32_t pin)
  369 {
  370         uint32_t reg_val;
  371 
  372         reg_val = mv_gpio_reg_read(reg);
  373         reg_val |= GPIO(pin);
  374         mv_gpio_reg_write(reg, reg_val);
  375 }
  376 
  377 static void
  378 mv_gpio_reg_clear(uint32_t reg, uint32_t pin)
  379 {
  380         uint32_t reg_val;
  381 
  382         reg_val = mv_gpio_reg_read(reg);
  383         reg_val &= ~(GPIO(pin));
  384         mv_gpio_reg_write(reg, reg_val);
  385 }
  386 
  387 static void
  388 mv_gpio_out_en(uint32_t pin, uint8_t enable)
  389 {
  390         uint32_t reg;
  391 
  392         if (pin >= mv_gpio_softc->pin_num)
  393                 return;
  394 
  395         if (pin >= GPIO_PINS_PER_REG) {
  396                 reg = GPIO_HI_DATA_OUT_EN_CTRL;
  397                 pin -= GPIO_PINS_PER_REG;
  398         } else
  399                 reg = GPIO_DATA_OUT_EN_CTRL;
  400 
  401         if (enable)
  402                 mv_gpio_reg_clear(reg, pin);
  403         else
  404                 mv_gpio_reg_set(reg, pin);
  405 }
  406 
  407 static void
  408 mv_gpio_blink(uint32_t pin, uint8_t enable)
  409 {
  410         uint32_t reg;
  411 
  412         if (pin >= mv_gpio_softc->pin_num)
  413                 return;
  414 
  415         if (pin >= GPIO_PINS_PER_REG) {
  416                 reg = GPIO_HI_BLINK_EN;
  417                 pin -= GPIO_PINS_PER_REG;
  418         } else
  419                 reg = GPIO_BLINK_EN;
  420 
  421         if (enable)
  422                 mv_gpio_reg_set(reg, pin);
  423         else
  424                 mv_gpio_reg_clear(reg, pin);
  425 }
  426 
  427 static void
  428 mv_gpio_polarity(uint32_t pin, uint8_t enable)
  429 {
  430         uint32_t reg;
  431 
  432         if (pin >= mv_gpio_softc->pin_num)
  433                 return;
  434 
  435         if (pin >= GPIO_PINS_PER_REG) {
  436                 reg = GPIO_HI_DATA_IN_POLAR;
  437                 pin -= GPIO_PINS_PER_REG;
  438         } else
  439                 reg = GPIO_DATA_IN_POLAR;
  440 
  441         if (enable)
  442                 mv_gpio_reg_set(reg, pin);
  443         else
  444                 mv_gpio_reg_clear(reg, pin);
  445 }
  446 
  447 static void
  448 mv_gpio_level(uint32_t pin, uint8_t enable)
  449 {
  450         uint32_t reg;
  451 
  452         if (pin >= mv_gpio_softc->pin_num)
  453                 return;
  454 
  455         if (pin >= GPIO_PINS_PER_REG) {
  456                 reg = GPIO_HI_INT_LEV_MASK;
  457                 pin -= GPIO_PINS_PER_REG;
  458         } else
  459                 reg = GPIO_INT_LEV_MASK;
  460 
  461         if (enable)
  462                 mv_gpio_reg_set(reg, pin);
  463         else
  464                 mv_gpio_reg_clear(reg, pin);
  465 }
  466 
  467 static void
  468 mv_gpio_edge(uint32_t pin, uint8_t enable)
  469 {
  470         uint32_t reg;
  471 
  472         if (pin >= mv_gpio_softc->pin_num)
  473                 return;
  474 
  475         if (pin >= GPIO_PINS_PER_REG) {
  476                 reg = GPIO_HI_INT_EDGE_MASK;
  477                 pin -= GPIO_PINS_PER_REG;
  478         } else
  479                 reg = GPIO_INT_EDGE_MASK;
  480 
  481         if (enable)
  482                 mv_gpio_reg_set(reg, pin);
  483         else
  484                 mv_gpio_reg_clear(reg, pin);
  485 }
  486 
  487 static void
  488 mv_gpio_int_ack(uint32_t pin)
  489 {
  490         uint32_t reg;
  491 
  492         if (pin >= mv_gpio_softc->pin_num)
  493                 return;
  494 
  495         if (pin >= GPIO_PINS_PER_REG) {
  496                 reg = GPIO_HI_INT_CAUSE;
  497                 pin -= GPIO_PINS_PER_REG;
  498         } else
  499                 reg = GPIO_INT_CAUSE;
  500 
  501         mv_gpio_reg_clear(reg, pin);
  502 }
  503 
  504 static uint32_t
  505 mv_gpio_value_get(uint32_t pin)
  506 {
  507         uint32_t reg, reg_val;
  508 
  509         if (pin >= mv_gpio_softc->pin_num)
  510                 return (0);
  511 
  512         if (pin >= GPIO_PINS_PER_REG) {
  513                 reg = GPIO_HI_DATA_IN;
  514                 pin -= GPIO_PINS_PER_REG;
  515         } else
  516                 reg = GPIO_DATA_IN;
  517 
  518         reg_val = mv_gpio_reg_read(reg);
  519 
  520         return (reg_val & GPIO(pin));
  521 }
  522 
  523 static void
  524 mv_gpio_value_set(uint32_t pin, uint8_t val)
  525 {
  526         uint32_t reg;
  527 
  528         if (pin >= mv_gpio_softc->pin_num)
  529                 return;
  530 
  531         if (pin >= GPIO_PINS_PER_REG) {
  532                 reg = GPIO_HI_DATA_OUT;
  533                 pin -= GPIO_PINS_PER_REG;
  534         } else
  535                 reg = GPIO_DATA_OUT;
  536 
  537         if (val)
  538                 mv_gpio_reg_set(reg, pin);
  539         else
  540                 mv_gpio_reg_clear(reg, pin);
  541 }
  542 
  543 static int
  544 mv_handle_gpios_prop(phandle_t ctrl, pcell_t *gpios, int len)
  545 {
  546         pcell_t gpio_cells, pincnt;
  547         int inc, t, tuples, tuple_size;
  548         int dir, flags, pin;
  549         u_long gpio_ctrl, size;
  550         struct mv_gpio_softc sc;
  551 
  552         pincnt = 0;
  553         if (!OF_hasprop(ctrl, "gpio-controller"))
  554                 /* Node is not a GPIO controller. */
  555                 return (ENXIO);
  556 
  557         if (OF_getencprop(ctrl, "#gpio-cells", &gpio_cells, sizeof(pcell_t)) < 0)
  558                 return (ENXIO);
  559         if (gpio_cells != 3)
  560                 return (ENXIO);
  561 
  562         tuple_size = gpio_cells * sizeof(pcell_t) + sizeof(phandle_t);
  563         tuples = len / tuple_size;
  564 
  565         if (fdt_regsize(ctrl, &gpio_ctrl, &size))
  566                 return (ENXIO);
  567 
  568         if (OF_getencprop(ctrl, "pin-count", &pincnt, sizeof(pcell_t)) < 0)
  569                 return (ENXIO);
  570         sc.pin_num = pincnt;
  571 
  572         /*
  573          * Skip controller reference, since controller's phandle is given
  574          * explicitly (in a function argument).
  575          */
  576         inc = sizeof(ihandle_t) / sizeof(pcell_t);
  577         gpios += inc;
  578 
  579         for (t = 0; t < tuples; t++) {
  580                 pin = gpios[0];
  581                 dir = gpios[1];
  582                 flags = gpios[2];
  583 
  584                 mv_gpio_configure(pin, flags);
  585 
  586                 if (dir == 1)
  587                         /* Input. */
  588                         mv_gpio_out_en(pin, 0);
  589                 else {
  590                         /* Output. */
  591                         if (flags & MV_GPIO_OUT_OPEN_DRAIN)
  592                                 mv_gpio_out(pin, 0, 1);
  593 
  594                         if (flags & MV_GPIO_OUT_OPEN_SRC)
  595                                 mv_gpio_out(pin, 1, 1);
  596                 }
  597                 gpios += gpio_cells + inc;
  598         }
  599 
  600         return (0);
  601 }
  602 
  603 #define MAX_PINS_PER_NODE       5
  604 #define GPIOS_PROP_CELLS        4
  605 static int
  606 mv_gpio_init(void)
  607 {
  608         phandle_t child, parent, root, ctrl;
  609         pcell_t gpios[MAX_PINS_PER_NODE * GPIOS_PROP_CELLS];
  610         struct gpio_ctrl_entry *e;
  611         int len, rv;
  612 
  613         root = OF_finddevice("/");
  614         len = 0;
  615         parent = root;
  616 
  617         /* Traverse through entire tree to find nodes with 'gpios' prop */
  618         for (child = OF_child(parent); child != 0; child = OF_peer(child)) {
  619 
  620                 /* Find a 'leaf'. Start the search from this node. */
  621                 while (OF_child(child)) {
  622                         parent = child;
  623                         child = OF_child(child);
  624                 }
  625                 if ((len = OF_getproplen(child, "gpios")) > 0) {
  626 
  627                         if (len > sizeof(gpios))
  628                                 return (ENXIO);
  629 
  630                         /* Get 'gpios' property. */
  631                         OF_getencprop(child, "gpios", gpios, len);
  632 
  633                         e = (struct gpio_ctrl_entry *)&gpio_controllers;
  634 
  635                         /* Find and call a handler. */
  636                         for (; e->compat; e++) {
  637                                 /*
  638                                  * First cell of 'gpios' property should
  639                                  * contain a ref. to a node defining GPIO
  640                                  * controller.
  641                                  */
  642                                 ctrl = OF_node_from_xref(gpios[0]);
  643 
  644                                 if (fdt_is_compatible(ctrl, e->compat))
  645                                         /* Call a handler. */
  646                                         if ((rv = e->handler(ctrl,
  647                                             (pcell_t *)&gpios, len)))
  648                                                 return (rv);
  649                         }
  650                 }
  651 
  652                 if (OF_peer(child) == 0) {
  653                         /* No more siblings. */
  654                         child = parent;
  655                         parent = OF_parent(child);
  656                 }
  657         }
  658         return (0);
  659 }

Cache object: 4df6631a8326fe9814eb940de62a4f66


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