xref: /src/sys/dev/fdt/dwiic_fdt.c

/* $NetBSD: dwiic_fdt.c,v 1.9 2025/09/16 11:55:17 thorpej Exp $ */

/*-
 * Copyright (c) 2017 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Manuel Bouyer.
 *
 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */
/*
 * Synopsys DesignWare I2C controller, FDT front-end
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: dwiic_fdt.c,v 1.9 2025/09/16 11:55:17 thorpej Exp $");

#include <sys/param.h>
#include <sys/systm.h>

#include <dev/fdt/fdtvar.h>
#include <dev/ic/dwiic_var.h>

static const struct device_compatible_entry compat_data[] = {
	{ .compat = "snps,designware-i2c" },
	DEVICE_COMPAT_EOL
};

struct dwiic_fdt_softc {
	struct dwiic_softc	sc_dwiic;
};

static int	dwiic_fdt_match(device_t, cfdata_t, void *);
static void	dwiic_fdt_attach(device_t, device_t, void *);

CFATTACH_DECL_NEW(dwiic_fdt, sizeof(struct dwiic_fdt_softc),
    dwiic_fdt_match, dwiic_fdt_attach, dwiic_detach, NULL);

int
dwiic_fdt_match(device_t parent, cfdata_t match, void *aux)
{
	struct fdt_attach_args * const faa = aux;

	return of_compatible_match(faa->faa_phandle, compat_data);
}

void
dwiic_fdt_attach(device_t parent, device_t self, void *aux)
{
	struct dwiic_fdt_softc * const sc = device_private(self);
	struct fdt_attach_args * const faa = aux;
	const int phandle = faa->faa_phandle;
	bus_addr_t addr;
	bus_size_t size;
	char intrstr[128];

	sc->sc_dwiic.sc_dev = self;
	sc->sc_dwiic.sc_power = NULL;
	sc->sc_dwiic.sc_type = dwiic_type_generic;

	if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) {
		aprint_error(": couldn't get registers\n");
		return;
	}

	sc->sc_dwiic.sc_iot = faa->faa_bst;
	if (bus_space_map(sc->sc_dwiic.sc_iot, addr, size, 0, &sc->sc_dwiic.sc_ioh) != 0) {
		aprint_error(": couldn't map registers\n");
		return;
	}

	/* enable clock(s) */
	struct clk *clk;
	u_int c;
	for (c = 0; (clk = fdtbus_clock_get_index(phandle, c)) != NULL; c++) {
		if (clk_enable(clk) != 0) {
			aprint_error(": couldn't enable clock #%d\n", c);
			goto failed_clock;
		}
	}
	if (c == 0) {
		aprint_error(": missing clock\n");
		goto failed_clock;
	}

	/* de-assert optional reset. */
	struct fdtbus_reset *rst = fdtbus_reset_get_index(phandle, 0);
	if (rst != NULL) {
		if (fdtbus_reset_deassert(rst) != 0) {
			aprint_error(": couldn't de-assert the reset\n");
			goto failed_reset;
		}
	}

	aprint_naive(": I2C controller\n");
	aprint_normal(": I2C controller\n");

	if (!fdtbus_intr_str(phandle, 0, intrstr, sizeof(intrstr))) {
		aprint_error_dev(self, "failed to decode interrupt\n");
		goto failed_intrstr;
	}
	aprint_normal_dev(self, "interrupting on %s\n", intrstr);

	sc->sc_dwiic.sc_ih = fdtbus_intr_establish_xname(phandle, 0, IPL_VM, 0,
		dwiic_intr, &sc->sc_dwiic, device_xname(self));
	if (sc->sc_dwiic.sc_ih == NULL) {
		aprint_error_dev(self, "couldn't establish interrupt\n");
		goto failed_intr;
	}

	if (!dwiic_attach(&sc->sc_dwiic))
		goto failed_attach;

	pmf_device_register(self, dwiic_suspend, dwiic_resume);

	iicbus_attach(self, &sc->sc_dwiic.sc_i2c_tag);

	return;

failed_attach:
	fdtbus_intr_disestablish(phandle, sc->sc_dwiic.sc_ih);

failed_intrstr:
failed_intr:
failed_reset:
failed_clock:
	bus_space_unmap(sc->sc_dwiic.sc_iot, sc->sc_dwiic.sc_ioh, size);
}