1 /*-
2 * Copyright (c) 2013 Oleksandr Tymoshenko <gonzo@freebsd.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/kernel.h>
34 #include <sys/limits.h>
35 #include <sys/lock.h>
36 #include <sys/module.h>
37 #include <sys/mutex.h>
38 #include <sys/resource.h>
39 #include <sys/rman.h>
40 #include <sys/sysctl.h>
41
42 #include <machine/bus.h>
43
44 #include <dev/ofw/openfirm.h>
45 #include <dev/ofw/ofw_bus.h>
46 #include <dev/ofw/ofw_bus_subr.h>
47
48 #include "am335x_pwm.h"
49
50 #define ECAP_TSCTR 0x00
51 #define ECAP_CAP1 0x08
52 #define ECAP_CAP2 0x0C
53 #define ECAP_CAP3 0x10
54 #define ECAP_CAP4 0x14
55 #define ECAP_ECCTL2 0x2A
56 #define ECCTL2_MODE_APWM (1 << 9)
57 #define ECCTL2_SYNCO_SEL (3 << 6)
58 #define ECCTL2_TSCTRSTOP_FREERUN (1 << 4)
59
60 #define ECAP_READ2(_sc, reg) bus_read_2((_sc)->sc_mem_res, reg);
61 #define ECAP_WRITE2(_sc, reg, value) \
62 bus_write_2((_sc)->sc_mem_res, reg, value);
63 #define ECAP_READ4(_sc, reg) bus_read_4((_sc)->sc_mem_res, reg);
64 #define ECAP_WRITE4(_sc, reg, value) \
65 bus_write_4((_sc)->sc_mem_res, reg, value);
66
67 #define PWM_LOCK(_sc) mtx_lock(&(_sc)->sc_mtx)
68 #define PWM_UNLOCK(_sc) mtx_unlock(&(_sc)->sc_mtx)
69 #define PWM_LOCK_INIT(_sc) mtx_init(&(_sc)->sc_mtx, \
70 device_get_nameunit(_sc->sc_dev), "am335x_ecap softc", MTX_DEF)
71 #define PWM_LOCK_DESTROY(_sc) mtx_destroy(&(_sc)->sc_mtx)
72
73 static device_probe_t am335x_ecap_probe;
74 static device_attach_t am335x_ecap_attach;
75 static device_detach_t am335x_ecap_detach;
76
77 struct am335x_ecap_softc {
78 device_t sc_dev;
79 struct mtx sc_mtx;
80 struct resource *sc_mem_res;
81 int sc_mem_rid;
82 };
83
84 static struct ofw_compat_data compat_data[] = {
85 {"ti,am3352-ecap", true},
86 {"ti,am33xx-ecap", true},
87 {NULL, false},
88 };
89 SIMPLEBUS_PNP_INFO(compat_data);
90
91 static device_method_t am335x_ecap_methods[] = {
92 DEVMETHOD(device_probe, am335x_ecap_probe),
93 DEVMETHOD(device_attach, am335x_ecap_attach),
94 DEVMETHOD(device_detach, am335x_ecap_detach),
95
96 DEVMETHOD_END
97 };
98
99 static driver_t am335x_ecap_driver = {
100 "am335x_ecap",
101 am335x_ecap_methods,
102 sizeof(struct am335x_ecap_softc),
103 };
104
105 /*
106 * API function to set period/duty cycles for ECAPx
107 */
108 int
109 am335x_pwm_config_ecap(int unit, int period, int duty)
110 {
111 device_t dev;
112 struct am335x_ecap_softc *sc;
113 uint16_t reg;
114
115 dev = devclass_get_device(devclass_find(am335x_ecap_driver.name), unit);
116 if (dev == NULL)
117 return (ENXIO);
118
119 if (duty > period)
120 return (EINVAL);
121
122 if (period == 0)
123 return (EINVAL);
124
125 sc = device_get_softc(dev);
126 PWM_LOCK(sc);
127
128 reg = ECAP_READ2(sc, ECAP_ECCTL2);
129 reg |= ECCTL2_MODE_APWM | ECCTL2_TSCTRSTOP_FREERUN | ECCTL2_SYNCO_SEL;
130 ECAP_WRITE2(sc, ECAP_ECCTL2, reg);
131
132 /* CAP3 in APWM mode is APRD shadow register */
133 ECAP_WRITE4(sc, ECAP_CAP3, period - 1);
134
135 /* CAP4 in APWM mode is ACMP shadow register */
136 ECAP_WRITE4(sc, ECAP_CAP4, duty);
137 /* Restart counter */
138 ECAP_WRITE4(sc, ECAP_TSCTR, 0);
139
140 PWM_UNLOCK(sc);
141
142 return (0);
143 }
144
145 static int
146 am335x_ecap_probe(device_t dev)
147 {
148
149 if (!ofw_bus_status_okay(dev))
150 return (ENXIO);
151
152 if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data)
153 return (ENXIO);
154
155 device_set_desc(dev, "AM335x eCAP");
156
157 return (BUS_PROBE_DEFAULT);
158 }
159
160 static int
161 am335x_ecap_attach(device_t dev)
162 {
163 struct am335x_ecap_softc *sc;
164
165 sc = device_get_softc(dev);
166 sc->sc_dev = dev;
167
168 PWM_LOCK_INIT(sc);
169
170 sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
171 &sc->sc_mem_rid, RF_ACTIVE);
172 if (sc->sc_mem_res == NULL) {
173 device_printf(dev, "cannot allocate memory resources\n");
174 goto fail;
175 }
176
177 return (0);
178
179 fail:
180 PWM_LOCK_DESTROY(sc);
181 return (ENXIO);
182 }
183
184 static int
185 am335x_ecap_detach(device_t dev)
186 {
187 struct am335x_ecap_softc *sc;
188
189 sc = device_get_softc(dev);
190
191 PWM_LOCK(sc);
192 if (sc->sc_mem_res)
193 bus_release_resource(dev, SYS_RES_MEMORY,
194 sc->sc_mem_rid, sc->sc_mem_res);
195 PWM_UNLOCK(sc);
196
197 PWM_LOCK_DESTROY(sc);
198
199 return (0);
200 }
201
202 DRIVER_MODULE(am335x_ecap, am335x_pwmss, am335x_ecap_driver, 0, 0);
203 MODULE_VERSION(am335x_ecap, 1);
204 MODULE_DEPEND(am335x_ecap, am335x_pwmss, 1, 1, 1);
Cache object: 149b33ee3207d37839b3d976ab8054af
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