xref: /freebsd/sys/dev/iicbus/controller/twsi/a10_twsi.c (revision 63f537551380d2dab29fa402ad1269feae17e594)
1 /*-
2  * Copyright (c) 2016-2019 Emmanuel Vadot <manu@freebsd.org>
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 #include <sys/param.h>
28 #include <sys/systm.h>
29 #include <sys/bus.h>
30 #include <sys/kernel.h>
31 #include <sys/module.h>
32 #include <sys/resource.h>
33 
34 #include <machine/bus.h>
35 #include <machine/resource.h>
36 
37 #include <sys/rman.h>
38 
39 #include <sys/lock.h>
40 #include <sys/mutex.h>
41 
42 #include <dev/iicbus/iiconf.h>
43 #include <dev/iicbus/iicbus.h>
44 #include <dev/iicbus/controller/twsi/twsi.h>
45 #include <dev/ofw/ofw_bus.h>
46 #include <dev/ofw/ofw_bus_subr.h>
47 
48 #include <dev/extres/clk/clk.h>
49 #include <dev/extres/hwreset/hwreset.h>
50 
51 #include "iicbus_if.h"
52 
53 #define	TWI_ADDR	0x0
54 #define	TWI_XADDR	0x4
55 #define	TWI_DATA	0x8
56 #define	TWI_CNTR	0xC
57 #define	TWI_STAT	0x10
58 #define	TWI_CCR		0x14
59 #define	TWI_SRST	0x18
60 #define	TWI_EFR		0x1C
61 #define	TWI_LCR		0x20
62 
63 static struct ofw_compat_data compat_data[] = {
64 	{"allwinner,sun4i-a10-i2c", 1},
65 	{"allwinner,sun6i-a31-i2c", 1},
66 	{"allwinner,sun8i-a83t-i2c", 1},
67 	{NULL, 0},
68 };
69 
70 static int
71 a10_twsi_probe(device_t dev)
72 {
73 
74 	if (!ofw_bus_status_okay(dev))
75 		return (ENXIO);
76 
77 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
78 		return (ENXIO);
79 
80 	device_set_desc(dev, "Allwinner Integrated I2C Bus Controller");
81 	return (BUS_PROBE_DEFAULT);
82 }
83 
84 static int
85 a10_twsi_attach(device_t dev)
86 {
87 	struct twsi_softc *sc;
88 	hwreset_t rst;
89 	int error;
90 
91 	sc = device_get_softc(dev);
92 
93 	/* De-assert reset */
94 	if (hwreset_get_by_ofw_idx(dev, 0, 0, &rst) == 0) {
95 		error = hwreset_deassert(rst);
96 		if (error != 0) {
97 			device_printf(dev, "could not de-assert reset\n");
98 			return (error);
99 		}
100 	}
101 
102 	/* Activate clock */
103 	error = clk_get_by_ofw_index(dev, 0, 0, &sc->clk_core);
104 	if (error != 0) {
105 		device_printf(dev, "could not find clock\n");
106 		return (error);
107 	}
108 	error = clk_enable(sc->clk_core);
109 	if (error != 0) {
110 		device_printf(dev, "could not enable clock\n");
111 		return (error);
112 	}
113 
114 	sc->reg_data = TWI_DATA;
115 	sc->reg_slave_addr = TWI_ADDR;
116 	sc->reg_slave_ext_addr = TWI_XADDR;
117 	sc->reg_control = TWI_CNTR;
118 	sc->reg_status = TWI_STAT;
119 	sc->reg_baud_rate = TWI_CCR;
120 	sc->reg_soft_reset = TWI_SRST;
121 
122 	if (ofw_bus_is_compatible(dev, "allwinner,sun6i-a31-i2c") ||
123 	    ofw_bus_is_compatible(dev, "allwinner,sun6i-a83t-i2c"))
124 		sc->iflag_w1c = true;
125 	return (twsi_attach(dev));
126 }
127 
128 static phandle_t
129 a10_twsi_get_node(device_t bus, device_t dev)
130 {
131 	return (ofw_bus_get_node(bus));
132 }
133 
134 static device_method_t a10_twsi_methods[] = {
135 	/* device interface */
136 	DEVMETHOD(device_probe,		a10_twsi_probe),
137 	DEVMETHOD(device_attach,	a10_twsi_attach),
138 
139 	/* OFW methods */
140 	DEVMETHOD(ofw_bus_get_node,	a10_twsi_get_node),
141 
142 	{ 0, 0 }
143 };
144 
145 DEFINE_CLASS_1(iichb, a10_twsi_driver, a10_twsi_methods,
146     sizeof(struct twsi_softc), twsi_driver);
147 
148 EARLY_DRIVER_MODULE(a10_twsi, simplebus, a10_twsi_driver,
149     0, 0, BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LATE);
150 EARLY_DRIVER_MODULE(iicbus, a10_twsi, iicbus_driver,
151     0, 0, BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LATE);
152 MODULE_DEPEND(a10_twsi, iicbus, 1, 1, 1);
153 SIMPLEBUS_PNP_INFO(compat_data);
154