2 * Copyright (c) 2016-2019 Emmanuel Vadot <manu@freebsd.org>
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
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.
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
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
29 #include <sys/param.h>
30 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/module.h>
34 #include <sys/resource.h>
36 #include <machine/bus.h>
37 #include <machine/resource.h>
42 #include <sys/mutex.h>
44 #include <dev/iicbus/iiconf.h>
45 #include <dev/iicbus/iicbus.h>
46 #include <dev/iicbus/twsi/twsi.h>
47 #include <dev/ofw/ofw_bus.h>
48 #include <dev/ofw/ofw_bus_subr.h>
50 #include <dev/extres/clk/clk.h>
51 #include <dev/extres/hwreset/hwreset.h>
53 #include "iicbus_if.h"
65 static struct ofw_compat_data compat_data[] = {
66 {"allwinner,sun4i-a10-i2c", 1},
67 {"allwinner,sun6i-a31-i2c", 1},
68 {"allwinner,sun8i-a83t-i2c", 1},
73 a10_twsi_probe(device_t dev)
76 if (!ofw_bus_status_okay(dev))
79 if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
82 device_set_desc(dev, "Allwinner Integrated I2C Bus Controller");
83 return (BUS_PROBE_DEFAULT);
87 a10_twsi_attach(device_t dev)
89 struct twsi_softc *sc;
95 sc = device_get_softc(dev);
98 if (hwreset_get_by_ofw_idx(dev, 0, 0, &rst) == 0) {
99 error = hwreset_deassert(rst);
101 device_printf(dev, "could not de-assert reset\n");
107 error = clk_get_by_ofw_index(dev, 0, 0, &clk);
109 device_printf(dev, "could not find clock\n");
112 error = clk_enable(clk);
114 device_printf(dev, "could not enable clock\n");
118 sc->reg_data = TWI_DATA;
119 sc->reg_slave_addr = TWI_ADDR;
120 sc->reg_slave_ext_addr = TWI_XADDR;
121 sc->reg_control = TWI_CNTR;
122 sc->reg_status = TWI_STAT;
123 sc->reg_baud_rate = TWI_CCR;
124 sc->reg_soft_reset = TWI_SRST;
126 /* Setup baud rate params */
127 clk_get_freq(clk, &freq);
131 * F0 = FINT / 2 ^ CLK_N
132 * F1 = F0 / (CLK_M + 1)
134 * Doc says that the output freq is F1/10 but my logic analyzer says otherwise
137 sc->baud_rate[IIC_SLOW].param = TWSI_BAUD_RATE_PARAM(11, 1);
138 sc->baud_rate[IIC_FAST].param = TWSI_BAUD_RATE_PARAM(11, 1);
139 sc->baud_rate[IIC_FASTEST].param = TWSI_BAUD_RATE_PARAM(2, 1);
142 sc->baud_rate[IIC_SLOW].param = TWSI_BAUD_RATE_PARAM(5, 2);
143 sc->baud_rate[IIC_FAST].param = TWSI_BAUD_RATE_PARAM(5, 2);
144 sc->baud_rate[IIC_FASTEST].param = TWSI_BAUD_RATE_PARAM(2, 2);
147 device_printf(dev, "Non supported frequency\n");
152 return (twsi_attach(dev));
156 a10_twsi_get_node(device_t bus, device_t dev)
158 return (ofw_bus_get_node(bus));
161 static device_method_t a10_twsi_methods[] = {
162 /* device interface */
163 DEVMETHOD(device_probe, a10_twsi_probe),
164 DEVMETHOD(device_attach, a10_twsi_attach),
167 DEVMETHOD(ofw_bus_get_node, a10_twsi_get_node),
172 DEFINE_CLASS_1(iichb, a10_twsi_driver, a10_twsi_methods,
173 sizeof(struct twsi_softc), twsi_driver);
175 static devclass_t a10_twsi_devclass;
177 EARLY_DRIVER_MODULE(a10_twsi, simplebus, a10_twsi_driver, a10_twsi_devclass,
178 0, 0, BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LATE);
179 EARLY_DRIVER_MODULE(iicbus, a10_twsi, iicbus_driver, iicbus_devclass,
180 0, 0, BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LATE);
181 MODULE_DEPEND(a10_twsi, iicbus, 1, 1, 1);