1 /*
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright 2021 Emmanuel Vadot <[email protected]>
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are
8 * met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
23 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
25 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
26 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/kernel.h>
35 #include <sys/module.h>
36 #include <sys/gpio.h>
37
38 #include <dev/gpio/gpiobusvar.h>
39 #include <dev/ofw/ofw_bus.h>
40 #include <dev/ofw/ofw_bus_subr.h>
41
42 #include <dev/extres/clk/clk.h>
43
44 #include "mmc_pwrseq_if.h"
45
46 enum pwrseq_type {
47 PWRSEQ_SIMPLE = 1,
48 PWRSEQ_EMMC,
49 };
50
51 static struct ofw_compat_data compat_data[] = {
52 { "mmc-pwrseq-simple", PWRSEQ_SIMPLE },
53 { "mmc-pwrseq-emmc", PWRSEQ_EMMC },
54 { NULL, 0 }
55 };
56
57 struct mmc_pwrseq_softc {
58 enum pwrseq_type type;
59 clk_t ext_clock;
60 struct gpiobus_pin *reset_gpio;
61
62 uint32_t post_power_on_delay_ms;
63 uint32_t power_off_delay_us;
64 };
65
66 static int
mmc_pwrseq_probe(device_t dev)67 mmc_pwrseq_probe(device_t dev)
68 {
69 enum pwrseq_type type;
70
71 if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data)
72 return (ENXIO);
73
74 type = (enum pwrseq_type)ofw_bus_search_compatible(dev, compat_data)->ocd_data;
75 switch (type) {
76 case PWRSEQ_SIMPLE:
77 device_set_desc(dev, "MMC Simple Power sequence");
78 break;
79 case PWRSEQ_EMMC:
80 device_set_desc(dev, "MMC eMMC Power sequence");
81 break;
82 }
83 return (BUS_PROBE_DEFAULT);
84 }
85
86 static int
mmc_pwrseq_attach(device_t dev)87 mmc_pwrseq_attach(device_t dev)
88 {
89 struct mmc_pwrseq_softc *sc;
90 phandle_t node;
91 int rv;
92
93 sc = device_get_softc(dev);
94 sc->type = (enum pwrseq_type)ofw_bus_search_compatible(dev, compat_data)->ocd_data;
95 node = ofw_bus_get_node(dev);
96
97 if (sc->type == PWRSEQ_SIMPLE) {
98 if (OF_hasprop(node, "clocks")) {
99 rv = clk_get_by_ofw_name(dev, 0, "ext_clock", &sc->ext_clock);
100 if (rv != 0) {
101 device_printf(dev,
102 "Node have a clocks property but no clocks named \"ext_clock\"\n");
103 return (ENXIO);
104 }
105 }
106 OF_getencprop(node, "post-power-on-delay-ms", &sc->post_power_on_delay_ms, sizeof(uint32_t));
107 OF_getencprop(node, "power-off-delay-us", &sc->power_off_delay_us, sizeof(uint32_t));
108 }
109
110 if (OF_hasprop(node, "reset-gpios")) {
111 if (gpio_pin_get_by_ofw_property(dev, node, "reset-gpios",
112 &sc->reset_gpio) != 0) {
113 device_printf(dev, "Cannot get the reset-gpios\n");
114 return (ENXIO);
115 }
116 gpio_pin_setflags(sc->reset_gpio, GPIO_PIN_OUTPUT);
117 gpio_pin_set_active(sc->reset_gpio, true);
118 }
119
120 OF_device_register_xref(OF_xref_from_node(node), dev);
121 return (0);
122 }
123
124 static int
mmc_pwrseq_detach(device_t dev)125 mmc_pwrseq_detach(device_t dev)
126 {
127
128 return (EBUSY);
129 }
130
131 static int
mmv_pwrseq_set_power(device_t dev,bool power_on)132 mmv_pwrseq_set_power(device_t dev, bool power_on)
133 {
134 struct mmc_pwrseq_softc *sc;
135 int rv;
136
137 sc = device_get_softc(dev);
138
139 if (power_on) {
140 if (sc->ext_clock) {
141 rv = clk_enable(sc->ext_clock);
142 if (rv != 0)
143 return (rv);
144 }
145
146 if (sc->reset_gpio) {
147 rv = gpio_pin_set_active(sc->reset_gpio, false);
148 if (rv != 0)
149 return (rv);
150 }
151
152 if (sc->post_power_on_delay_ms)
153 DELAY(sc->post_power_on_delay_ms * 1000);
154 } else {
155 if (sc->reset_gpio) {
156 rv = gpio_pin_set_active(sc->reset_gpio, true);
157 if (rv != 0)
158 return (rv);
159 }
160
161 if (sc->ext_clock) {
162 rv = clk_stop(sc->ext_clock);
163 if (rv != 0)
164 return (rv);
165 }
166 if (sc->power_off_delay_us)
167 DELAY(sc->power_off_delay_us);
168 }
169
170 return (0);
171 }
172
173 static device_method_t mmc_pwrseq_methods[] = {
174 /* Device interface */
175 DEVMETHOD(device_probe, mmc_pwrseq_probe),
176 DEVMETHOD(device_attach, mmc_pwrseq_attach),
177 DEVMETHOD(device_detach, mmc_pwrseq_detach),
178
179 DEVMETHOD(mmc_pwrseq_set_power, mmv_pwrseq_set_power),
180 DEVMETHOD_END
181 };
182
183 static driver_t mmc_pwrseq_driver = {
184 "mmc_pwrseq",
185 mmc_pwrseq_methods,
186 sizeof(struct mmc_pwrseq_softc),
187 };
188
189 static devclass_t mmc_pwrseq_devclass;
190
191 EARLY_DRIVER_MODULE(mmc_pwrseq, simplebus, mmc_pwrseq_driver, mmc_pwrseq_devclass, 0, 0,
192 BUS_PASS_SUPPORTDEV + BUS_PASS_ORDER_FIRST);
193 MODULE_VERSION(mmc_pwrseq, 1);
194 SIMPLEBUS_PNP_INFO(compat_data);
195