1 /*
2 * SPDX-License-Identifier: BSD-2-Clause
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 #include <sys/param.h>
31 #include <sys/bus.h>
32 #include <sys/kernel.h>
33 #include <sys/module.h>
34 #include <sys/gpio.h>
35
36 #include <dev/gpio/gpiobusvar.h>
37 #include <dev/ofw/ofw_bus.h>
38 #include <dev/ofw/ofw_bus_subr.h>
39
40 #include <dev/extres/clk/clk.h>
41
42 #include "mmc_pwrseq_if.h"
43
44 enum pwrseq_type {
45 PWRSEQ_SIMPLE = 1,
46 PWRSEQ_EMMC,
47 };
48
49 static struct ofw_compat_data compat_data[] = {
50 { "mmc-pwrseq-simple", PWRSEQ_SIMPLE },
51 { "mmc-pwrseq-emmc", PWRSEQ_EMMC },
52 { NULL, 0 }
53 };
54
55 struct mmc_pwrseq_softc {
56 enum pwrseq_type type;
57 clk_t ext_clock;
58 struct gpiobus_pin *reset_gpio;
59
60 uint32_t post_power_on_delay_ms;
61 uint32_t power_off_delay_us;
62 };
63
64 static int
mmc_pwrseq_probe(device_t dev)65 mmc_pwrseq_probe(device_t dev)
66 {
67 enum pwrseq_type type;
68
69 if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data)
70 return (ENXIO);
71
72 type = (enum pwrseq_type)ofw_bus_search_compatible(dev, compat_data)->ocd_data;
73 switch (type) {
74 case PWRSEQ_SIMPLE:
75 device_set_desc(dev, "MMC Simple Power sequence");
76 break;
77 case PWRSEQ_EMMC:
78 device_set_desc(dev, "MMC eMMC Power sequence");
79 break;
80 }
81 return (BUS_PROBE_DEFAULT);
82 }
83
84 static int
mmc_pwrseq_attach(device_t dev)85 mmc_pwrseq_attach(device_t dev)
86 {
87 struct mmc_pwrseq_softc *sc;
88 phandle_t node;
89 int rv;
90
91 sc = device_get_softc(dev);
92 sc->type = (enum pwrseq_type)ofw_bus_search_compatible(dev, compat_data)->ocd_data;
93 node = ofw_bus_get_node(dev);
94
95 if (sc->type == PWRSEQ_SIMPLE) {
96 if (OF_hasprop(node, "clocks")) {
97 rv = clk_get_by_ofw_name(dev, 0, "ext_clock", &sc->ext_clock);
98 if (rv != 0) {
99 device_printf(dev,
100 "Node have a clocks property but no clocks named \"ext_clock\"\n");
101 return (ENXIO);
102 }
103 }
104 OF_getencprop(node, "post-power-on-delay-ms", &sc->post_power_on_delay_ms, sizeof(uint32_t));
105 OF_getencprop(node, "power-off-delay-us", &sc->power_off_delay_us, sizeof(uint32_t));
106 }
107
108 if (OF_hasprop(node, "reset-gpios")) {
109 if (gpio_pin_get_by_ofw_property(dev, node, "reset-gpios",
110 &sc->reset_gpio) != 0) {
111 device_printf(dev, "Cannot get the reset-gpios\n");
112 return (ENXIO);
113 }
114 gpio_pin_setflags(sc->reset_gpio, GPIO_PIN_OUTPUT);
115 gpio_pin_set_active(sc->reset_gpio, true);
116 }
117
118 OF_device_register_xref(OF_xref_from_node(node), dev);
119 return (0);
120 }
121
122 static int
mmc_pwrseq_detach(device_t dev)123 mmc_pwrseq_detach(device_t dev)
124 {
125
126 return (EBUSY);
127 }
128
129 static int
mmv_pwrseq_set_power(device_t dev,bool power_on)130 mmv_pwrseq_set_power(device_t dev, bool power_on)
131 {
132 struct mmc_pwrseq_softc *sc;
133 int rv;
134
135 sc = device_get_softc(dev);
136
137 if (power_on) {
138 if (sc->ext_clock) {
139 rv = clk_enable(sc->ext_clock);
140 if (rv != 0)
141 return (rv);
142 }
143
144 if (sc->reset_gpio) {
145 rv = gpio_pin_set_active(sc->reset_gpio, false);
146 if (rv != 0)
147 return (rv);
148 }
149
150 if (sc->post_power_on_delay_ms)
151 DELAY(sc->post_power_on_delay_ms * 1000);
152 } else {
153 if (sc->reset_gpio) {
154 rv = gpio_pin_set_active(sc->reset_gpio, true);
155 if (rv != 0)
156 return (rv);
157 }
158
159 if (sc->ext_clock) {
160 rv = clk_stop(sc->ext_clock);
161 if (rv != 0)
162 return (rv);
163 }
164 if (sc->power_off_delay_us)
165 DELAY(sc->power_off_delay_us);
166 }
167
168 return (0);
169 }
170
171 static device_method_t mmc_pwrseq_methods[] = {
172 /* Device interface */
173 DEVMETHOD(device_probe, mmc_pwrseq_probe),
174 DEVMETHOD(device_attach, mmc_pwrseq_attach),
175 DEVMETHOD(device_detach, mmc_pwrseq_detach),
176
177 DEVMETHOD(mmc_pwrseq_set_power, mmv_pwrseq_set_power),
178 DEVMETHOD_END
179 };
180
181 static driver_t mmc_pwrseq_driver = {
182 "mmc_pwrseq",
183 mmc_pwrseq_methods,
184 sizeof(struct mmc_pwrseq_softc),
185 };
186
187 EARLY_DRIVER_MODULE(mmc_pwrseq, simplebus, mmc_pwrseq_driver, 0, 0,
188 BUS_PASS_SUPPORTDEV + BUS_PASS_ORDER_FIRST);
189 MODULE_VERSION(mmc_pwrseq, 1);
190 SIMPLEBUS_PNP_INFO(compat_data);
191