jbus-i2c.c revision 1.1
1/*	$NetBSD: jbus-i2c.c,v 1.1 2018/10/20 06:25:46 macallan Exp $	*/
2
3/*
4 * Copyright (c) 2018 Michael Lorenz
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 AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19 * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
20 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
24 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
25 * 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__KERNEL_RCSID(0, "$NetBSD: jbus-i2c.c,v 1.1 2018/10/20 06:25:46 macallan Exp $");
31
32#include <sys/param.h>
33#include <sys/device.h>
34#include <sys/errno.h>
35
36#include <sys/bus.h>
37#include <machine/autoconf.h>
38
39#include <dev/i2c/i2cvar.h>
40#include <dev/i2c/i2c_bitbang.h>
41
42#include <dev/pci/pcivar.h>
43#include <dev/pci/pcireg.h>
44#include <sparc64/dev/iommureg.h>
45#include <sparc64/dev/iommuvar.h>
46#include <sparc64/dev/schizovar.h>
47#include <sparc64/dev/schizoreg.h>
48#include <machine/openfirm.h>
49
50#define DPRINTF printf
51
52/* I2C glue */
53static int jbusi2c_i2c_acquire_bus(void *, int);
54static void jbusi2c_i2c_release_bus(void *, int);
55static int jbusi2c_i2c_send_start(void *, int);
56static int jbusi2c_i2c_send_stop(void *, int);
57static int jbusi2c_i2c_initiate_xfer(void *, i2c_addr_t, int);
58static int jbusi2c_i2c_read_byte(void *, uint8_t *, int);
59static int jbusi2c_i2c_write_byte(void *, uint8_t, int);
60
61/* I2C bitbang glue */
62static void jbusi2c_i2cbb_set_bits(void *, uint32_t);
63static void jbusi2c_i2cbb_set_dir(void *, uint32_t);
64static uint32_t jbusi2c_i2cbb_read(void *);
65
66static const struct i2c_bitbang_ops jbusi2c_i2cbb_ops = {
67	jbusi2c_i2cbb_set_bits,
68	jbusi2c_i2cbb_set_dir,
69	jbusi2c_i2cbb_read,
70	{
71		2,	/* bit 1 is data */
72		1,	/* bit 0 is clock */
73		3,	/* direction register for both out */
74		1	/* data in, clock out */
75	}
76};
77
78static	int	jbusi2c_match(device_t, cfdata_t, void *);
79static	void	jbusi2c_attach(device_t, device_t, void *);
80
81struct jbusi2c_softc {
82	device_t sc_dev;
83	struct i2c_controller sc_i2c;
84	kmutex_t sc_i2c_lock;
85	int sc_node;
86};
87
88static void jbusi2c_setup_i2c(struct jbusi2c_softc *);
89
90CFATTACH_DECL_NEW(jbusi2c, sizeof(struct jbusi2c_softc),
91    jbusi2c_match, jbusi2c_attach, NULL, NULL);
92
93extern struct schizo_softc *schizo0;
94
95int
96jbusi2c_match(device_t parent, cfdata_t match, void *aux)
97{
98	struct mainbus_attach_args *ma = aux;
99	char *str;
100
101	if (strcmp(ma->ma_name, "i2c") != 0)
102		return (0);
103
104	str = prom_getpropstring(ma->ma_node, "compatible");
105	if (strcmp(str, "jbus-i2c") == 0)
106		return (1);
107
108	return (0);
109}
110
111void
112jbusi2c_attach(device_t parent, device_t self, void *aux)
113{
114	struct jbusi2c_softc *sc = device_private(self);
115	struct mainbus_attach_args *ma = aux;
116
117	aprint_normal("\n");
118
119	sc->sc_dev = self;
120	sc->sc_node = ma->ma_node;
121
122	if (schizo0 != NULL)
123		jbusi2c_setup_i2c(sc);
124}
125
126
127
128static void
129jbusi2c_setup_i2c(struct jbusi2c_softc *sc)
130{
131	struct i2cbus_attach_args iba;
132	prop_array_t cfg;
133	prop_dictionary_t dev;
134	prop_data_t data;
135	prop_dictionary_t dict = device_properties(sc->sc_dev);
136	int ret, devs, regs[2], addr;
137	uint8_t reg = 0, val[128];
138	char name[64], compat[256];
139
140	sc->sc_i2c.ic_cookie = schizo0;
141	sc->sc_i2c.ic_acquire_bus = jbusi2c_i2c_acquire_bus;
142	sc->sc_i2c.ic_release_bus = jbusi2c_i2c_release_bus;
143	sc->sc_i2c.ic_send_start = jbusi2c_i2c_send_start;
144	sc->sc_i2c.ic_send_stop = jbusi2c_i2c_send_stop;
145	sc->sc_i2c.ic_initiate_xfer = jbusi2c_i2c_initiate_xfer;
146	sc->sc_i2c.ic_read_byte = jbusi2c_i2c_read_byte;
147	sc->sc_i2c.ic_write_byte = jbusi2c_i2c_write_byte;
148	sc->sc_i2c.ic_exec = NULL;
149
150	val[0] = 0;
151	ret = iic_exec(&sc->sc_i2c, I2C_OP_READ_WITH_STOP, 0x50,
152		    &reg, 1, val, 1, I2C_F_POLL);
153	printf("ret %d val %02x\n", ret, val[0]);
154
155	/* round up i2c devices */
156	devs = OF_child(sc->sc_node);
157	cfg = prop_array_create();
158	prop_dictionary_set(dict, "i2c-child-devices", cfg);
159	prop_object_release(cfg);
160	while (devs != 0) {
161		if (OF_getprop(devs, "name", name, 256) <= 0)
162			goto skip;
163		memset(compat, 0, sizeof(compat));
164		if (OF_getprop(devs, "compatible",
165		    compat, 255) <= 0)
166			goto skip;
167		if (OF_getprop(devs, "reg", regs, 8) <= 0)
168			goto skip;
169		if (regs[0] != 0) goto skip;
170		addr = (regs[1] & 0xff) >> 1;
171		DPRINTF("-> %s@%d,%x\n", name, regs[0], addr);
172		dev = prop_dictionary_create();
173		prop_dictionary_set_cstring(dev, "name", name);
174		data = prop_data_create_data(compat, strlen(compat)+1);
175		prop_dictionary_set(dev, "compatible", data);
176		prop_object_release(data);
177		prop_dictionary_set_uint32(dev, "addr", addr);
178		prop_dictionary_set_uint64(dev, "cookie", devs);
179		prop_array_add(cfg, dev);
180		prop_object_release(dev);
181	skip:
182		devs = OF_peer(devs);
183	}
184	memset(&iba, 0, sizeof(iba));
185	iba.iba_tag = &sc->sc_i2c;
186	mutex_init(&sc->sc_i2c_lock, MUTEX_DEFAULT, IPL_NONE);
187	config_found_ia(sc->sc_dev, "i2cbus", &iba,
188	    iicbus_print);
189}
190
191/* I2C bitbanging */
192static void
193jbusi2c_i2cbb_set_bits(void *cookie, uint32_t bits)
194{
195	struct schizo_softc *sc = cookie;
196
197	schizo_write(sc, SCZ_JBUS_GPIO_DATA, bits);
198}
199
200static void
201jbusi2c_i2cbb_set_dir(void *cookie, uint32_t dir)
202{
203	struct schizo_softc *sc = cookie;
204
205	schizo_write(sc, SCZ_JBUS_GPIO_DIR, dir);
206}
207
208static uint32_t
209jbusi2c_i2cbb_read(void *cookie)
210{
211	struct schizo_softc *sc = cookie;
212
213	return schizo_read(sc, SCZ_JBUS_GPIO_DATA);
214}
215
216/* higher level I2C stuff */
217static int
218jbusi2c_i2c_acquire_bus(void *cookie, int flags)
219{
220
221	/* private bus */
222	return 0;
223}
224
225static void
226jbusi2c_i2c_release_bus(void *cookie, int flags)
227{
228
229	/* private bus */
230}
231
232static int
233jbusi2c_i2c_send_start(void *cookie, int flags)
234{
235
236	return i2c_bitbang_send_start(cookie, flags, &jbusi2c_i2cbb_ops);
237}
238
239static int
240jbusi2c_i2c_send_stop(void *cookie, int flags)
241{
242
243	return i2c_bitbang_send_stop(cookie, flags, &jbusi2c_i2cbb_ops);
244}
245
246static int
247jbusi2c_i2c_initiate_xfer(void *cookie, i2c_addr_t addr, int flags)
248{
249
250	return i2c_bitbang_initiate_xfer(cookie, addr, flags,
251	    &jbusi2c_i2cbb_ops);
252}
253
254static int
255jbusi2c_i2c_read_byte(void *cookie, uint8_t *valp, int flags)
256{
257
258	return i2c_bitbang_read_byte(cookie, valp, flags, &jbusi2c_i2cbb_ops);
259}
260
261static int
262jbusi2c_i2c_write_byte(void *cookie, uint8_t val, int flags)
263{
264
265	return i2c_bitbang_write_byte(cookie, val, flags, &jbusi2c_i2cbb_ops);
266}
267