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/fdt/fdt_common.h>
45 #include <dev/ofw/openfirm.h>
46 #include <dev/ofw/ofw_bus.h>
47 #include <dev/ofw/ofw_bus_subr.h>
48
49 #include "am335x_pwm.h"
50
51 #define ECAP_TSCTR 0x00
52 #define ECAP_CAP1 0x08
53 #define ECAP_CAP2 0x0C
54 #define ECAP_CAP3 0x10
55 #define ECAP_CAP4 0x14
56 #define ECAP_ECCTL2 0x2A
57 #define ECCTL2_MODE_APWM (1 << 9)
58 #define ECCTL2_SYNCO_SEL (3 << 6)
59 #define ECCTL2_TSCTRSTOP_FREERUN (1 << 4)
60
61 #define ECAP_READ2(_sc, reg) bus_read_2((_sc)->sc_mem_res, reg);
62 #define ECAP_WRITE2(_sc, reg, value) \
63 bus_write_2((_sc)->sc_mem_res, reg, value);
64 #define ECAP_READ4(_sc, reg) bus_read_4((_sc)->sc_mem_res, reg);
65 #define ECAP_WRITE4(_sc, reg, value) \
66 bus_write_4((_sc)->sc_mem_res, reg, value);
67
68 #define PWM_LOCK(_sc) mtx_lock(&(_sc)->sc_mtx)
69 #define PWM_UNLOCK(_sc) mtx_unlock(&(_sc)->sc_mtx)
70 #define PWM_LOCK_INIT(_sc) mtx_init(&(_sc)->sc_mtx, \
71 device_get_nameunit(_sc->sc_dev), "am335x_ecap softc", MTX_DEF)
72 #define PWM_LOCK_DESTROY(_sc) mtx_destroy(&(_sc)->sc_mtx)
73
74 static device_probe_t am335x_ecap_probe;
75 static device_attach_t am335x_ecap_attach;
76 static device_detach_t am335x_ecap_detach;
77
78 struct am335x_ecap_softc {
79 device_t sc_dev;
80 struct mtx sc_mtx;
81 struct resource *sc_mem_res;
82 int sc_mem_rid;
83 };
84
85 static device_method_t am335x_ecap_methods[] = {
86 DEVMETHOD(device_probe, am335x_ecap_probe),
87 DEVMETHOD(device_attach, am335x_ecap_attach),
88 DEVMETHOD(device_detach, am335x_ecap_detach),
89
90 DEVMETHOD_END
91 };
92
93 static driver_t am335x_ecap_driver = {
94 "am335x_ecap",
95 am335x_ecap_methods,
96 sizeof(struct am335x_ecap_softc),
97 };
98
99 static devclass_t am335x_ecap_devclass;
100
101 /*
102 * API function to set period/duty cycles for ECAPx
103 */
104 int
am335x_pwm_config_ecap(int unit,int period,int duty)105 am335x_pwm_config_ecap(int unit, int period, int duty)
106 {
107 device_t dev;
108 struct am335x_ecap_softc *sc;
109 uint16_t reg;
110
111 dev = devclass_get_device(am335x_ecap_devclass, unit);
112 if (dev == NULL)
113 return (ENXIO);
114
115 if (duty > period)
116 return (EINVAL);
117
118 if (period == 0)
119 return (EINVAL);
120
121 sc = device_get_softc(dev);
122 PWM_LOCK(sc);
123
124 reg = ECAP_READ2(sc, ECAP_ECCTL2);
125 reg |= ECCTL2_MODE_APWM | ECCTL2_TSCTRSTOP_FREERUN | ECCTL2_SYNCO_SEL;
126 ECAP_WRITE2(sc, ECAP_ECCTL2, reg);
127
128 /* CAP3 in APWM mode is APRD shadow register */
129 ECAP_WRITE4(sc, ECAP_CAP3, period - 1);
130
131 /* CAP4 in APWM mode is ACMP shadow register */
132 ECAP_WRITE4(sc, ECAP_CAP4, duty);
133 /* Restart counter */
134 ECAP_WRITE4(sc, ECAP_TSCTR, 0);
135
136 PWM_UNLOCK(sc);
137
138 return (0);
139 }
140
141 static int
am335x_ecap_probe(device_t dev)142 am335x_ecap_probe(device_t dev)
143 {
144
145 if (!ofw_bus_status_okay(dev))
146 return (ENXIO);
147
148 if (!ofw_bus_is_compatible(dev, "ti,am33xx-ecap"))
149 return (ENXIO);
150
151 device_set_desc(dev, "AM335x eCAP");
152
153 return (BUS_PROBE_DEFAULT);
154 }
155
156 static int
am335x_ecap_attach(device_t dev)157 am335x_ecap_attach(device_t dev)
158 {
159 struct am335x_ecap_softc *sc;
160
161 sc = device_get_softc(dev);
162 sc->sc_dev = dev;
163
164 PWM_LOCK_INIT(sc);
165
166 sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
167 &sc->sc_mem_rid, RF_ACTIVE);
168 if (sc->sc_mem_res == NULL) {
169 device_printf(dev, "cannot allocate memory resources\n");
170 goto fail;
171 }
172
173 return (0);
174
175 fail:
176 PWM_LOCK_DESTROY(sc);
177 return (ENXIO);
178 }
179
180 static int
am335x_ecap_detach(device_t dev)181 am335x_ecap_detach(device_t dev)
182 {
183 struct am335x_ecap_softc *sc;
184
185 sc = device_get_softc(dev);
186
187 PWM_LOCK(sc);
188 if (sc->sc_mem_res)
189 bus_release_resource(dev, SYS_RES_MEMORY,
190 sc->sc_mem_rid, sc->sc_mem_res);
191 PWM_UNLOCK(sc);
192
193 PWM_LOCK_DESTROY(sc);
194
195
196 return (0);
197 }
198
199 DRIVER_MODULE(am335x_ecap, am335x_pwmss, am335x_ecap_driver, am335x_ecap_devclass, 0, 0);
200 MODULE_VERSION(am335x_ecap, 1);
201 MODULE_DEPEND(am335x_ecap, am335x_pwmss, 1, 1, 1);
202