sunxi_twi.c revision 1.2 
1/* $NetBSD: sunxi_twi.c,v 1.2 2017/07/01 22:49:09 jmcneill Exp $ */
2
3/*-
4 * Copyright (c) 2017 Jared McNeill <jmcneill@invisible.ca>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include <sys/cdefs.h>
30
31__KERNEL_RCSID(0, "$NetBSD: sunxi_twi.c,v 1.2 2017/07/01 22:49:09 jmcneill Exp $");
32
33#include <sys/param.h>
34#include <sys/bus.h>
35#include <sys/device.h>
36#include <sys/intr.h>
37#include <sys/systm.h>
38#include <sys/time.h>
39
40#include <dev/i2c/i2cvar.h>
41#include <dev/i2c/gttwsivar.h>
42
43#include <dev/fdt/fdtvar.h>
44
45static int sunxi_twi_match(device_t, cfdata_t, void *);
46static void sunxi_twi_attach(device_t, device_t, void *);
47
48static const char * const compatible[] = {
49	"allwinner,sun6i-a31-i2c",
50	NULL
51};
52
53CFATTACH_DECL_NEW(sunxi_twi, sizeof(struct gttwsi_softc),
54	sunxi_twi_match, sunxi_twi_attach, NULL, NULL);
55
56static i2c_tag_t
57sunxi_twi_get_tag(device_t dev)
58{
59	struct gttwsi_softc * const sc = device_private(dev);
60
61	return &sc->sc_i2c;
62}
63
64const struct fdtbus_i2c_controller_func sunxi_twi_funcs = {
65	.get_tag = sunxi_twi_get_tag,
66};
67
68static int
69sunxi_twi_match(device_t parent, cfdata_t cf, void *aux)
70{
71	struct fdt_attach_args * const faa = aux;
72
73	return of_match_compatible(faa->faa_phandle, compatible);
74}
75
76static void
77sunxi_twi_attach(device_t parent, device_t self, void *aux)
78{
79	struct gttwsi_softc * const sc = device_private(self);
80	struct fdt_attach_args * const faa = aux;
81	struct i2cbus_attach_args iba;
82	const int phandle = faa->faa_phandle;
83	bus_space_tag_t bst = faa->faa_bst;
84	bus_space_handle_t bsh;
85	prop_dictionary_t devs;
86	uint32_t address_cells;
87	struct fdtbus_reset *rst;
88	struct clk *clk;
89	char intrstr[128];
90	bus_addr_t addr;
91	bus_size_t size;
92	void *ih;
93
94	if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) {
95		aprint_error(": couldn't get registers\n");
96		return;
97	}
98
99	if (bus_space_map(bst, addr, size, 0, &bsh) != 0) {
100		aprint_error(": couldn't map registers\n");
101		return;
102	}
103
104	if (!fdtbus_intr_str(phandle, 0, intrstr, sizeof(intrstr))) {
105		aprint_error(": failed to decode interrupt\n");
106		return;
107	}
108
109	if ((clk = fdtbus_clock_get_index(phandle, 0)) != NULL)
110		if (clk_enable(clk) != 0) {
111			aprint_error(": couldn't enable clock\n");
112			return;
113		}
114	if ((rst = fdtbus_reset_get_index(phandle, 0)) != NULL)
115		if (fdtbus_reset_deassert(rst) != 0) {
116			aprint_error(": couldn't de-assert reset\n");
117			return;
118		}
119
120	gttwsi_attach_subr(self, bst, bsh);
121
122	ih = fdtbus_intr_establish(phandle, 0, IPL_VM, 0, gttwsi_intr, sc);
123	if (ih == NULL) {
124		aprint_error_dev(self, "couldn't establish interrupt on %s\n",
125		    intrstr);
126		return;
127	}
128	aprint_normal_dev(self, "interrupting on %s\n", intrstr);
129
130	fdtbus_register_i2c_controller(self, phandle, &sunxi_twi_funcs);
131
132	devs = prop_dictionary_create();
133	if (of_getprop_uint32(phandle, "#address-cells", &address_cells))
134		address_cells = 1;
135
136	of_enter_i2c_devs(devs, phandle, address_cells * 4, 0);
137
138	memset(&iba, 0, sizeof(iba));
139	iba.iba_tag = &sc->sc_i2c;
140	iba.iba_child_devices = prop_dictionary_get(devs, "i2c-child-devices");
141	if (iba.iba_child_devices)
142		prop_object_retain(iba.iba_child_devices);
143	else
144		iba.iba_child_devices = prop_array_create();
145	prop_object_release(devs);
146
147	config_found_ia(self, "i2cbus", &iba, iicbus_print);
148}
149