/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* 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 "opt_platform.h"
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/systm.h>
#include <dev/iicbus/iicbus.h>
#include <dev/iicbus/iiconf.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <dev/ofw/openfirm.h>
#include "iicbus_if.h"
#include "iicmux_if.h"
static struct ofw_compat_data compat_data[] = {
{"nxp,pca9547", 1},
{NULL, 0}
};
#include <dev/iicbus/mux/iicmux.h>
struct pca9547_softc {
struct iicmux_softc mux;
device_t dev;
bool idle_disconnect;
};
static int
pca9547_bus_select(device_t dev, int busidx, struct iic_reqbus_data *rd)
{
struct pca9547_softc *sc = device_get_softc(dev);
uint8_t busbits;
/*
* The iicmux caller ensures busidx is between 0 and the number of buses
* we passed to iicmux_init_softc(), no need for validation here. If
* the fdt data has the idle_disconnect property we idle the bus by
* selecting no downstream buses, otherwise we just leave the current
* bus active. The upper bits of control register 3 activate the
* downstream buses; bit 7 is the first bus, bit 6 the second, etc.
*/
if (busidx == IICMUX_SELECT_IDLE) {
if (sc->idle_disconnect)
busbits = 0;
else
return (0);
} else {
busbits = 0x8 | (busidx & 0x7);
}
/*
* We have to add the IIC_RECURSIVE flag because the iicmux core has
* already reserved the bus for us, and iicdev_writeto() is going to try
* to reserve it again, which is allowed with the recursive flag.
*/
return (iicdev_writeto(dev, busbits, NULL, 0,
rd->flags | IIC_RECURSIVE));
}
static int
pca9547_probe(device_t dev)
{
if (!ofw_bus_status_okay(dev))
return (ENXIO);
if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data)
return (ENXIO);
device_set_desc(dev, "PCA9547 IIC bus multiplexor");
return (BUS_PROBE_DEFAULT);
}
static int
pca9547_attach(device_t dev)
{
struct pca9547_softc *sc;
phandle_t node;
int rv;
sc = device_get_softc(dev);
sc ->dev = dev;
node = ofw_bus_get_node(dev);
sc->idle_disconnect = OF_hasprop(node, "i2c-mux-idle-disconnect");
rv = iicmux_attach(sc->dev, device_get_parent(dev), 8);
if (rv != 0)
return (rv);
rv = bus_generic_attach(dev);
return (rv);
}
static int
pca9547_detach(device_t dev)
{
int rv;
rv = iicmux_detach(dev);
if (rv != 0)
return (rv);
return (0);
}
static device_method_t pca9547_methods[] = {
/* device methods */
DEVMETHOD(device_probe, pca9547_probe),
DEVMETHOD(device_attach, pca9547_attach),
DEVMETHOD(device_detach, pca9547_detach),
/* iicmux methods */
DEVMETHOD(iicmux_bus_select, pca9547_bus_select),
DEVMETHOD_END
};
static devclass_t pca9547_devclass;
DEFINE_CLASS_1(iicmux, pca9547_driver, pca9547_methods,
sizeof(struct pca9547_softc), iicmux_driver);
DRIVER_MODULE(pca_iicmux, iicbus, pca9547_driver, pca9547_devclass, 0, 0);
IICBUS_FDT_PNP_INFO(compat_data);
DRIVER_MODULE(iicbus, iicmux, iicbus_driver, iicbus_devclass, 0, 0);
DRIVER_MODULE(ofw_iicbus, iicmux, ofw_iicbus_driver, ofw_iicbus_devclass,
0, 0);
MODULE_DEPEND(pca9547, iicmux, 1, 1, 1);
MODULE_DEPEND(pca9547, iicbus, 1, 1, 1);
