/* $NetBSD: sunxi_twi.c,v 1.2.4.2 2017/07/18 19:13:09 snj Exp $ */

/*-
 * Copyright (c) 2017 Jared McNeill <jmcneill@invisible.ca>
 * 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 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.
 */

#include <sys/cdefs.h>

__KERNEL_RCSID(0, "$NetBSD: sunxi_twi.c,v 1.2.4.2 2017/07/18 19:13:09 snj Exp $");

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/device.h>
#include <sys/intr.h>
#include <sys/systm.h>
#include <sys/time.h>

#include <dev/i2c/i2cvar.h>
#include <dev/i2c/gttwsivar.h>

#include <dev/fdt/fdtvar.h>

static int sunxi_twi_match(device_t, cfdata_t, void *);
static void sunxi_twi_attach(device_t, device_t, void *);

static const char * const compatible[] = {
	"allwinner,sun6i-a31-i2c",
	NULL
};

CFATTACH_DECL_NEW(sunxi_twi, sizeof(struct gttwsi_softc),
	sunxi_twi_match, sunxi_twi_attach, NULL, NULL);

static i2c_tag_t
sunxi_twi_get_tag(device_t dev)
{
	struct gttwsi_softc * const sc = device_private(dev);

	return &sc->sc_i2c;
}

const struct fdtbus_i2c_controller_func sunxi_twi_funcs = {
	.get_tag = sunxi_twi_get_tag,
};

static int
sunxi_twi_match(device_t parent, cfdata_t cf, void *aux)
{
	struct fdt_attach_args * const faa = aux;

	return of_match_compatible(faa->faa_phandle, compatible);
}

static void
sunxi_twi_attach(device_t parent, device_t self, void *aux)
{
	struct gttwsi_softc * const sc = device_private(self);
	struct fdt_attach_args * const faa = aux;
	struct i2cbus_attach_args iba;
	const int phandle = faa->faa_phandle;
	bus_space_tag_t bst = faa->faa_bst;
	bus_space_handle_t bsh;
	prop_dictionary_t devs;
	uint32_t address_cells;
	struct fdtbus_reset *rst;
	struct clk *clk;
	char intrstr[128];
	bus_addr_t addr;
	bus_size_t size;
	void *ih;

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

	if (bus_space_map(bst, addr, size, 0, &bsh) != 0) {
		aprint_error(": couldn't map registers\n");
		return;
	}

	if (!fdtbus_intr_str(phandle, 0, intrstr, sizeof(intrstr))) {
		aprint_error(": failed to decode interrupt\n");
		return;
	}

	if ((clk = fdtbus_clock_get_index(phandle, 0)) != NULL)
		if (clk_enable(clk) != 0) {
			aprint_error(": couldn't enable clock\n");
			return;
		}
	if ((rst = fdtbus_reset_get_index(phandle, 0)) != NULL)
		if (fdtbus_reset_deassert(rst) != 0) {
			aprint_error(": couldn't de-assert reset\n");
			return;
		}

	gttwsi_attach_subr(self, bst, bsh);

	ih = fdtbus_intr_establish(phandle, 0, IPL_VM, 0, gttwsi_intr, sc);
	if (ih == NULL) {
		aprint_error_dev(self, "couldn't establish interrupt on %s\n",
		    intrstr);
		return;
	}
	aprint_normal_dev(self, "interrupting on %s\n", intrstr);

	fdtbus_register_i2c_controller(self, phandle, &sunxi_twi_funcs);

	devs = prop_dictionary_create();
	if (of_getprop_uint32(phandle, "#address-cells", &address_cells))
		address_cells = 1;

	of_enter_i2c_devs(devs, phandle, address_cells * 4, 0);

	memset(&iba, 0, sizeof(iba));
	iba.iba_tag = &sc->sc_i2c;
	iba.iba_child_devices = prop_dictionary_get(devs, "i2c-child-devices");
	if (iba.iba_child_devices)
		prop_object_retain(iba.iba_child_devices);
	else
		iba.iba_child_devices = prop_array_create();
	prop_object_release(devs);

	config_found_ia(self, "i2cbus", &iba, iicbus_print);
}