xref: /netbsd-src/sys/dev/i2c/lm_i2c.c (revision 77c8c4e6710b7b5cba3f6a8d733c76c3b5f9809b)
1 /*	$NetBSD: lm_i2c.c,v 1.7 2021/06/13 09:48:44 mlelstv Exp $	*/
2 
3 /*-
4  * Copyright (c) 2000 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Bill Squier.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: lm_i2c.c,v 1.7 2021/06/13 09:48:44 mlelstv Exp $");
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/device.h>
39 #include <sys/conf.h>
40 #include <sys/kmem.h>
41 
42 #include <dev/i2c/i2cvar.h>
43 
44 #include <dev/sysmon/sysmonvar.h>
45 
46 #include <dev/ic/nslm7xvar.h>
47 
48 int 	lm_i2c_match(device_t, cfdata_t, void *);
49 void 	lm_i2c_attach(device_t, device_t, void *);
50 int 	lm_i2c_detach(device_t, int);
51 
52 uint8_t lm_i2c_readreg(struct lm_softc *, int);
53 void 	lm_i2c_writereg(struct lm_softc *, int, uint8_t);
54 
55 struct lm_i2c_softc {
56 	struct lm_softc sc_lmsc;
57 	i2c_tag_t sc_tag;
58 	i2c_addr_t sc_addr;
59 };
60 
61 CFATTACH_DECL_NEW(lm_iic, sizeof(struct lm_i2c_softc),
62     lm_i2c_match, lm_i2c_attach, lm_i2c_detach, NULL);
63 
64 int
lm_i2c_match(device_t parent,cfdata_t match,void * aux)65 lm_i2c_match(device_t parent, cfdata_t match, void *aux)
66 {
67 	struct i2c_attach_args *ia = aux;
68 	int rv = 0;
69 	struct lm_i2c_softc *sc;
70 
71 	/* Must supply an address */
72 	if (ia->ia_addr < 1)
73 		return 0;
74 
75 	/* XXXJRT filter addresses //at all// please? */
76 
77 	/* Bus independent probe */
78 	sc = kmem_zalloc(sizeof(*sc), KM_SLEEP);
79 	sc->sc_lmsc.lm_writereg = lm_i2c_writereg;
80 	sc->sc_lmsc.lm_readreg = lm_i2c_readreg;
81 	sc->sc_tag = ia->ia_tag;
82 	sc->sc_addr = ia->ia_addr;
83 	rv = lm_match(&sc->sc_lmsc);
84 	kmem_free(sc, sizeof(*sc));
85 
86 	return rv ? I2C_MATCH_ADDRESS_AND_PROBE : 0;
87 }
88 
89 
90 void
lm_i2c_attach(device_t parent,device_t self,void * aux)91 lm_i2c_attach(device_t parent, device_t self, void *aux)
92 {
93 	struct lm_i2c_softc *sc = device_private(self);
94 	struct i2c_attach_args *ia = aux;
95 
96 	sc->sc_tag = ia->ia_tag;
97 	sc->sc_addr = ia->ia_addr;
98 
99 	/* Bus-independent attachment */
100 	sc->sc_lmsc.sc_dev = self;
101 	sc->sc_lmsc.lm_writereg = lm_i2c_writereg;
102 	sc->sc_lmsc.lm_readreg = lm_i2c_readreg;
103 
104 	lm_attach(&sc->sc_lmsc);
105 }
106 
107 int
lm_i2c_detach(device_t self,int flags)108 lm_i2c_detach(device_t self, int flags)
109 {
110 	struct lm_i2c_softc *sc = device_private(self);
111 
112 	lm_detach(&sc->sc_lmsc);
113 	return 0;
114 }
115 
116 uint8_t
lm_i2c_readreg(struct lm_softc * lmsc,int reg)117 lm_i2c_readreg(struct lm_softc *lmsc, int reg)
118 {
119 	struct lm_i2c_softc *sc = (struct lm_i2c_softc *)lmsc;
120 	uint8_t cmd, data;
121 
122 	if (iic_acquire_bus(sc->sc_tag, 0))
123 		return 0;
124 
125 	cmd = reg;
126 	iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
127 		 sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0);
128 
129 	iic_release_bus(sc->sc_tag, 0);
130 
131 	return data;
132 }
133 
134 
135 void
lm_i2c_writereg(struct lm_softc * lmsc,int reg,uint8_t val)136 lm_i2c_writereg(struct lm_softc *lmsc, int reg, uint8_t val)
137 {
138 	struct lm_i2c_softc *sc = (struct lm_i2c_softc *)lmsc;
139 	uint8_t cmd, data;
140 
141 	if (iic_acquire_bus(sc->sc_tag, 0))
142 		return;
143 
144 	cmd = reg;
145 	data = val;
146 	iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
147 		 sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0);
148 
149 	iic_release_bus(sc->sc_tag, 0);
150 }
151