text: /*-
   * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   *
   * Copyright (c) 2019 Ian Lepore <ian@FreeBSD.org>
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   */
  
  #include <sys/cdefs.h>
  __FBSDID("$FreeBSD$");
  
  #include <sys/param.h>
  #include <sys/bus.h>
  #include <sys/kernel.h>
  #include <sys/libkern.h>
  #include <sys/lock.h>
  #include <sys/module.h>
  
  #include <dev/fdt/fdt_common.h>
  #include <dev/ofw/ofw_bus.h>
  #include <dev/ofw/ofw_bus_subr.h>
  #include <dev/ofw/openfirm.h>
  #include <dev/pwm/pwmbus.h>
  
  #include "pwmbus_if.h"
  
  struct ofw_pwmbus_ivars {
  	struct pwmbus_ivars	base;
  	struct ofw_bus_devinfo	devinfo;
  };
  
  struct ofw_pwmbus_softc {
  	struct pwmbus_softc	base;
  };
  
  /*
   * bus_if methods...
   */
  
  static device_t
  ofw_pwmbus_add_child(device_t dev, u_int order, const char *name, int unit)
  {
  	device_t child;
  	struct ofw_pwmbus_ivars *ivars;
  
  	if ((ivars = malloc(sizeof(struct ofw_pwmbus_ivars), M_DEVBUF,
  	    M_NOWAIT | M_ZERO)) == NULL) {
  		return (NULL);
  	}
  
  	if ((child = device_add_child_ordered(dev, order, name, unit)) == NULL) {
  		free(ivars, M_DEVBUF);
  		return (NULL);
  	}
  
  	ivars->devinfo.obd_node = -1;
  	device_set_ivars(child, ivars);
  
  	return (child);
  }
  
  static void
  ofw_pwmbus_child_deleted(device_t dev, device_t child)
  {
  	struct ofw_pwmbus_ivars *ivars;
  
  	ivars = device_get_ivars(child);
  	if (ivars != NULL) {
  		ofw_bus_gen_destroy_devinfo(&ivars->devinfo);
  		free(ivars, M_DEVBUF);
  	}
  }
  
  static const struct ofw_bus_devinfo *
  ofw_pwmbus_get_devinfo(device_t bus, device_t dev)
  {
  	struct ofw_pwmbus_ivars *ivars;
  
  	ivars = device_get_ivars(dev);
  	return (&ivars->devinfo);
  }
  
  /*
   * device_if methods...
   */
  
  static int
  ofw_pwmbus_probe(device_t dev)
  {
  
  	if (ofw_bus_get_node(dev) == -1) {
  		return (ENXIO);
  	}
  	device_set_desc(dev, "OFW PWM bus");
  
  	return (BUS_PROBE_DEFAULT);
  }
  
  static int
  ofw_pwmbus_attach(device_t dev)
  {
  	struct ofw_pwmbus_softc *sc;
  	struct ofw_pwmbus_ivars *ivars;
  	phandle_t node;
  	device_t child, parent;
  	pcell_t  chan;
  	bool any_children;
  
  	sc = device_get_softc(dev);
  	sc->base.dev = dev;
  	parent = device_get_parent(dev);
  
  	if (PWMBUS_CHANNEL_COUNT(parent, &sc->base.nchannels) != 0 ||
  	    sc->base.nchannels == 0) {
  		device_printf(dev, "No channels on parent %s\n",
  		    device_get_nameunit(parent));
  		return (ENXIO);
  	}
  
  	/*
  	 * Attach the children found in the fdt node of the hardware controller.
  	 * Hardware controllers must implement the ofw_bus_get_node method so
  	 * that our call to ofw_bus_get_node() gets back the controller's node.
  	 */
  	any_children = false;
  	node = ofw_bus_get_node(dev);
  	for (node = OF_child(node); node != 0; node = OF_peer(node)) {
  		/*
  		 * The child has to have a reg property; its value is the
  		 * channel number so range-check it.
  		 */
  		if (OF_getencprop(node, "reg", &chan, sizeof(chan)) == -1)
  			continue;
  		if (chan >= sc->base.nchannels)
  			continue;
  
  		if ((child = ofw_pwmbus_add_child(dev, 0, NULL, -1)) == NULL)
  			continue;
  
  		ivars = device_get_ivars(child);
  		ivars->base.pi_channel = chan;
  
  		/* Set up the standard ofw devinfo. */
  		if (ofw_bus_gen_setup_devinfo(&ivars->devinfo, node) != 0) {
  			device_delete_child(dev, child);
  			continue;
  		}
  		any_children = true;
  	}
  
  	/*
  	 * If we didn't find any children in the fdt data, add a pwmc(4) child
  	 * for each channel, like the base pwmbus does.  The idea is that if
  	 * there is any fdt data, then we do exactly what it says and nothing
  	 * more, otherwise we just provide generic userland access to all the
  	 * pwm channels that exist like the base pwmbus's attach code does.
  	 */
  	if (!any_children) {
  		for (chan = 0; chan < sc->base.nchannels; ++chan) {
  			child = ofw_pwmbus_add_child(dev, 0, "pwmc", -1);
  			if (child == NULL) {
  				device_printf(dev, "failed to add pwmc child "
  				    " device for channel %u\n", chan);
  				continue;
  			}
  			ivars = device_get_ivars(child);
  			ivars->base.pi_channel = chan;
  		}
  	}
  	bus_enumerate_hinted_children(dev);
  	bus_generic_probe(dev);
  
  	return (bus_generic_attach(dev));
  }
  
  static device_method_t ofw_pwmbus_methods[] = {
  	/* Device interface */
  	DEVMETHOD(device_probe,           ofw_pwmbus_probe),
  	DEVMETHOD(device_attach,          ofw_pwmbus_attach),
  
  	/* Bus interface */
  	DEVMETHOD(bus_child_pnpinfo_str,  ofw_bus_gen_child_pnpinfo_str),
  	DEVMETHOD(bus_add_child,          ofw_pwmbus_add_child),
  	DEVMETHOD(bus_child_deleted,      ofw_pwmbus_child_deleted),
  
  	/* ofw_bus interface */
  	DEVMETHOD(ofw_bus_get_devinfo,    ofw_pwmbus_get_devinfo),
  	DEVMETHOD(ofw_bus_get_compat,     ofw_bus_gen_get_compat),
  	DEVMETHOD(ofw_bus_get_model,      ofw_bus_gen_get_model),
  	DEVMETHOD(ofw_bus_get_name,       ofw_bus_gen_get_name),
  	DEVMETHOD(ofw_bus_get_node,       ofw_bus_gen_get_node),
  	DEVMETHOD(ofw_bus_get_type,       ofw_bus_gen_get_type),
  
  	DEVMETHOD_END
  };
  
  devclass_t ofw_pwmbus_devclass;
  
  DEFINE_CLASS_1(pwmbus, ofw_pwmbus_driver, ofw_pwmbus_methods,
      sizeof(struct pwmbus_softc), pwmbus_driver);
  EARLY_DRIVER_MODULE(ofw_pwmbus, pwm, ofw_pwmbus_driver, ofw_pwmbus_devclass,
      0, 0, BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
  MODULE_VERSION(ofw_pwmbus, 1);
  MODULE_DEPEND(ofw_pwmbus, pwmbus, 1, 1, 1);
  