root/sys/arm/freescale/imx/imx6_hdmi.c
/*-
 * Copyright (c) 2015 Oleksandr Tymoshenko <gonzo@freebsd.org>
 * All rights reserved.
 *
 * 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>
/*
 * HDMI core module
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/eventhandler.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/bus.h>
#include <sys/rman.h>

#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>

#include <machine/bus.h>

#include <dev/videomode/videomode.h>
#include <dev/videomode/edidvar.h>

#include <arm/freescale/imx/imx_ccmvar.h>
#include <arm/freescale/imx/imx_iomuxvar.h>
#include <arm/freescale/imx/imx_iomuxreg.h>

#include <dev/hdmi/dwc_hdmi.h>

#include "crtc_if.h"

struct imx_hdmi_softc {
        struct dwc_hdmi_softc   base;
        phandle_t               i2c_xref;
        eventhandler_tag        eh_tag;
};

static struct ofw_compat_data compat_data[] = {
        {"fsl,imx6dl-hdmi", 1},
        {"fsl,imx6q-hdmi",  1},
        {NULL,              0}
};

static device_t
imx_hdmi_get_i2c_dev(device_t dev)
{
        struct imx_hdmi_softc *sc;

        sc = device_get_softc(dev);

        if (sc->i2c_xref == 0)
                return (NULL);

        return (OF_device_from_xref(sc->i2c_xref));
}

/*
 * Deferred HDMI init.  dwc_hdmi_init() does i2c transfers for DDC/EDID. The imx
 * i2c devices also use a config_intrhook function to finish their init, because
 * they require interrupts to perform transfers.  There is no way to control
 * whether the i2c or our hdmi intrhook function runs first.  If we go first we
 * have to continue waiting until after the i2c driver is ready to do transfers
 * and has registered its phandle.
 *
 * This function is used as both a config_intrhook function and after that as an
 * eventhandler callback function (if necessary), to see if our i2c device is
 * ready yet.  When it is, continue with hdmi init.  When first called as an
 * intrhook function the i2c devices might be ready, in which case we never
 * register as an eventhandler at all.  Otherwise we register to see newbus
 * attach events, and as each device attaches we check to see whether it was the
 * i2c device we care about.  Once we have our i2c device we unregister from
 * seeing further attach events.
 */
static void
imx_hdmi_init(void *dev)
{
        struct imx_hdmi_softc *sc;

        sc = device_get_softc((device_t)dev);

        if (OF_device_from_xref(sc->i2c_xref) != NULL) {
                if (sc->eh_tag != NULL) {
                        EVENTHANDLER_DEREGISTER_NOWAIT(device_attach,
                            sc->eh_tag);
                }
                dwc_hdmi_init(dev);
                return;
        }

        if (bootverbose)
                device_printf((device_t)dev, "Waiting for DDC i2c device\n");

        if (sc->eh_tag == NULL) {
                sc->eh_tag = EVENTHANDLER_REGISTER(device_attach, 
                    imx_hdmi_init, dev, EVENTHANDLER_PRI_ANY);
        }
}

static int
imx_hdmi_detach(device_t dev)
{
        struct imx_hdmi_softc *sc;

        sc = device_get_softc(dev);

        if (sc->base.sc_mem_res != NULL)
                bus_release_resource(dev, SYS_RES_MEMORY,
                    sc->base.sc_mem_rid, sc->base.sc_mem_res);

        return (0);
}

static int
imx_hdmi_attach(device_t dev)
{
        struct imx_hdmi_softc *sc;
        int err;
        uint32_t gpr3;
        phandle_t node, i2c_xref;

        sc = device_get_softc(dev);
        sc->base.sc_dev = dev;
        sc->base.sc_get_i2c_dev = imx_hdmi_get_i2c_dev;
        err = 0;

        /* Allocate memory resources. */
        sc->base.sc_mem_rid = 0;
        sc->base.sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
            &sc->base.sc_mem_rid, RF_ACTIVE);
        if (sc->base.sc_mem_res == NULL) {
                device_printf(dev, "Cannot allocate memory resources\n");
                err = ENXIO;
                goto out;
        }

        node = ofw_bus_get_node(dev);
        if (OF_getencprop(node, "ddc-i2c-bus", &i2c_xref, sizeof(i2c_xref)) == -1)
                sc->i2c_xref = 0;
        else
                sc->i2c_xref = i2c_xref;

        imx_ccm_hdmi_enable();

        gpr3 = imx_iomux_gpr_get(IOMUXC_GPR3);
        gpr3 &= ~(IOMUXC_GPR3_HDMI_MASK);
        gpr3 |= IOMUXC_GPR3_HDMI_IPU1_DI0;
        imx_iomux_gpr_set(IOMUXC_GPR3, gpr3);

        /* Further HDMI init requires interrupts for i2c transfers. */
        config_intrhook_oneshot(imx_hdmi_init, dev);
        return (0);

out:
        imx_hdmi_detach(dev);

        return (err);
}

static int
imx_hdmi_probe(device_t dev)
{

        if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
                return (ENXIO);

        device_set_desc(dev, "Freescale i.MX6 HDMI core");

        return (BUS_PROBE_DEFAULT);
}

static device_method_t imx_hdmi_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe,  imx_hdmi_probe),
        DEVMETHOD(device_attach, imx_hdmi_attach),
        DEVMETHOD(device_detach, imx_hdmi_detach),

        /* CRTC methods */
        DEVMETHOD(crtc_get_edid,        dwc_hdmi_get_edid),
        DEVMETHOD(crtc_set_videomode,   dwc_hdmi_set_videomode),

        DEVMETHOD_END
};

static driver_t imx_hdmi_driver = {
        "hdmi",
        imx_hdmi_methods,
        sizeof(struct imx_hdmi_softc)
};

DRIVER_MODULE(hdmi, simplebus, imx_hdmi_driver, 0, 0);