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/param.h>
28 #include <sys/systm.h>
29 #include <sys/bus.h>
30 #include <sys/kernel.h>
31 #include <sys/limits.h>
32 #include <sys/lock.h>
33 #include <sys/module.h>
34 #include <sys/mutex.h>
35 #include <sys/resource.h>
36 #include <sys/rman.h>
37 #include <sys/sysctl.h>
38
39 #include <machine/bus.h>
40
41 #include <dev/ofw/openfirm.h>
42 #include <dev/ofw/ofw_bus.h>
43 #include <dev/ofw/ofw_bus_subr.h>
44
45 #include "am335x_pwm.h"
46
47 #define ECAP_TSCTR 0x00
48 #define ECAP_CAP1 0x08
49 #define ECAP_CAP2 0x0C
50 #define ECAP_CAP3 0x10
51 #define ECAP_CAP4 0x14
52 #define ECAP_ECCTL2 0x2A
53 #define ECCTL2_MODE_APWM (1 << 9)
54 #define ECCTL2_SYNCO_SEL (3 << 6)
55 #define ECCTL2_TSCTRSTOP_FREERUN (1 << 4)
56
57 #define ECAP_READ2(_sc, reg) bus_read_2((_sc)->sc_mem_res, reg);
58 #define ECAP_WRITE2(_sc, reg, value) \
59 bus_write_2((_sc)->sc_mem_res, reg, value);
60 #define ECAP_READ4(_sc, reg) bus_read_4((_sc)->sc_mem_res, reg);
61 #define ECAP_WRITE4(_sc, reg, value) \
62 bus_write_4((_sc)->sc_mem_res, reg, value);
63
64 #define PWM_LOCK(_sc) mtx_lock(&(_sc)->sc_mtx)
65 #define PWM_UNLOCK(_sc) mtx_unlock(&(_sc)->sc_mtx)
66 #define PWM_LOCK_INIT(_sc) mtx_init(&(_sc)->sc_mtx, \
67 device_get_nameunit(_sc->sc_dev), "am335x_ecap softc", MTX_DEF)
68 #define PWM_LOCK_DESTROY(_sc) mtx_destroy(&(_sc)->sc_mtx)
69
70 static device_probe_t am335x_ecap_probe;
71 static device_attach_t am335x_ecap_attach;
72 static device_detach_t am335x_ecap_detach;
73
74 struct am335x_ecap_softc {
75 device_t sc_dev;
76 struct mtx sc_mtx;
77 struct resource *sc_mem_res;
78 int sc_mem_rid;
79 };
80
81 static struct ofw_compat_data compat_data[] = {
82 {"ti,am3352-ecap", true},
83 {"ti,am33xx-ecap", true},
84 {NULL, false},
85 };
86 SIMPLEBUS_PNP_INFO(compat_data);
87
88 static device_method_t am335x_ecap_methods[] = {
89 DEVMETHOD(device_probe, am335x_ecap_probe),
90 DEVMETHOD(device_attach, am335x_ecap_attach),
91 DEVMETHOD(device_detach, am335x_ecap_detach),
92
93 DEVMETHOD_END
94 };
95
96 static driver_t am335x_ecap_driver = {
97 "am335x_ecap",
98 am335x_ecap_methods,
99 sizeof(struct am335x_ecap_softc),
100 };
101
102 /*
103 * API function to set period/duty cycles for ECAPx
104 */
105 int
am335x_pwm_config_ecap(int unit,int period,int duty)106 am335x_pwm_config_ecap(int unit, int period, int duty)
107 {
108 device_t dev;
109 struct am335x_ecap_softc *sc;
110 uint16_t reg;
111
112 dev = devclass_get_device(devclass_find(am335x_ecap_driver.name), unit);
113 if (dev == NULL)
114 return (ENXIO);
115
116 if (duty > period)
117 return (EINVAL);
118
119 if (period == 0)
120 return (EINVAL);
121
122 sc = device_get_softc(dev);
123 PWM_LOCK(sc);
124
125 reg = ECAP_READ2(sc, ECAP_ECCTL2);
126 reg |= ECCTL2_MODE_APWM | ECCTL2_TSCTRSTOP_FREERUN | ECCTL2_SYNCO_SEL;
127 ECAP_WRITE2(sc, ECAP_ECCTL2, reg);
128
129 /* CAP3 in APWM mode is APRD shadow register */
130 ECAP_WRITE4(sc, ECAP_CAP3, period - 1);
131
132 /* CAP4 in APWM mode is ACMP shadow register */
133 ECAP_WRITE4(sc, ECAP_CAP4, duty);
134 /* Restart counter */
135 ECAP_WRITE4(sc, ECAP_TSCTR, 0);
136
137 PWM_UNLOCK(sc);
138
139 return (0);
140 }
141
142 static int
am335x_ecap_probe(device_t dev)143 am335x_ecap_probe(device_t dev)
144 {
145
146 if (!ofw_bus_status_okay(dev))
147 return (ENXIO);
148
149 if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data)
150 return (ENXIO);
151
152 device_set_desc(dev, "AM335x eCAP");
153
154 return (BUS_PROBE_DEFAULT);
155 }
156
157 static int
am335x_ecap_attach(device_t dev)158 am335x_ecap_attach(device_t dev)
159 {
160 struct am335x_ecap_softc *sc;
161
162 sc = device_get_softc(dev);
163 sc->sc_dev = dev;
164
165 PWM_LOCK_INIT(sc);
166
167 sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
168 &sc->sc_mem_rid, RF_ACTIVE);
169 if (sc->sc_mem_res == NULL) {
170 device_printf(dev, "cannot allocate memory resources\n");
171 goto fail;
172 }
173
174 return (0);
175
176 fail:
177 PWM_LOCK_DESTROY(sc);
178 return (ENXIO);
179 }
180
181 static int
am335x_ecap_detach(device_t dev)182 am335x_ecap_detach(device_t dev)
183 {
184 struct am335x_ecap_softc *sc;
185
186 sc = device_get_softc(dev);
187
188 PWM_LOCK(sc);
189 if (sc->sc_mem_res)
190 bus_release_resource(dev, SYS_RES_MEMORY,
191 sc->sc_mem_rid, sc->sc_mem_res);
192 PWM_UNLOCK(sc);
193
194 PWM_LOCK_DESTROY(sc);
195
196 return (0);
197 }
198
199 DRIVER_MODULE(am335x_ecap, am335x_pwmss, am335x_ecap_driver, 0, 0);
200 MODULE_VERSION(am335x_ecap, 1);
201 MODULE_DEPEND(am335x_ecap, am335x_pwmss, 1, 1, 1);
202