pl061gpio_fdt.c revision 1.1.2.3 1 /* $NetBSD: pl061gpio_fdt.c,v 1.1.2.3 2018/09/06 06:55:49 pgoyette Exp $ */
2
3 /*
4 * Copyright (c) 2018 Jonathan A. Kollasch
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
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 COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
20 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
21 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
23 * OR 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 __KERNEL_RCSID(0, "$NetBSD: pl061gpio_fdt.c,v 1.1.2.3 2018/09/06 06:55:49 pgoyette Exp $");
31
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/device.h>
35 #include <sys/intr.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/kmem.h>
39 #include <sys/gpio.h>
40
41 #include <dev/gpio/gpiovar.h>
42 #include "gpio.h"
43
44 #include <dev/ic/pl061reg.h>
45
46 #include <dev/fdt/fdtvar.h>
47
48 static int pl061_gpio_match(device_t, cfdata_t, void *);
49 static void pl061_gpio_attach(device_t, device_t, void *);
50
51 static void * pl061_gpio_fdt_acquire(device_t, const void *,
52 size_t, int);
53 static void pl061_gpio_fdt_release(device_t, void *);
54 static int pl061_gpio_fdt_read(device_t, void *, bool);
55 static void pl061_gpio_fdt_write(device_t, void *, int, bool);
56
57 struct fdtbus_gpio_controller_func pl061_gpio_funcs = {
58 .acquire = pl061_gpio_fdt_acquire,
59 .release = pl061_gpio_fdt_release,
60 .read = pl061_gpio_fdt_read,
61 .write = pl061_gpio_fdt_write
62 };
63
64 struct pl061_gpio_softc {
65 device_t sc_dev;
66 bus_space_tag_t sc_bst;
67 bus_space_handle_t sc_bsh;
68
69 struct gpio_chipset_tag sc_gc;
70 gpio_pin_t sc_pins[8];
71 };
72
73 struct pl061_gpio_pin {
74 struct pl061_gpio_softc *pin_sc;
75 int pin_no;
76 u_int pin_flags;
77 bool pin_actlo;
78 };
79
80 static int pl061_gpio_pin_read(void *, int);
81 static void pl061_gpio_pin_write(void *, int, int);
82 static void pl061_gpio_pin_ctl(void *, int, int);
83
84 CFATTACH_DECL_NEW(pl061gpio_fdt, sizeof(struct pl061_gpio_softc),
85 pl061_gpio_match, pl061_gpio_attach, NULL, NULL);
86
87 #define PL061_WRITE(sc, reg, val) \
88 bus_space_write_1((sc)->sc_bst, (sc)->sc_bsh, (reg)/4, (val))
89 #define PL061_READ(sc, reg) \
90 bus_space_read_1((sc)->sc_bst, (sc)->sc_bsh, (reg)/4)
91
92 static int
93 pl061_gpio_match(device_t parent, cfdata_t cf, void *aux)
94 {
95 const char * const compatible[] = {
96 "arm,pl061",
97 NULL
98 };
99 struct fdt_attach_args * const faa = aux;
100
101 return of_match_compatible(faa->faa_phandle, compatible);
102 }
103
104 static void
105 pl061_gpio_attach(device_t parent, device_t self, void *aux)
106 {
107 struct pl061_gpio_softc * const sc = device_private(self);
108 struct fdt_attach_args * const faa = aux;
109 bus_addr_t addr;
110 bus_size_t size;
111 int error;
112 struct gpiobus_attach_args gba;
113 u_int pin;
114
115
116 if (fdtbus_get_reg(faa->faa_phandle, 0, &addr, &size) != 0) {
117 aprint_error(": couldn't get registers\n");
118 return;
119 }
120
121 sc->sc_dev = self;
122 sc->sc_bst = faa->faa_a4x_bst;
123 error = bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh);
124 if (error) {
125 aprint_error(": couldn't map %#"PRIx64": %d", (uint64_t)addr, error);
126 return;
127 }
128
129 aprint_naive("\n");
130 aprint_normal(": GPIO\n");
131
132 sc->sc_gc.gp_cookie = sc;
133 sc->sc_gc.gp_pin_read = pl061_gpio_pin_read;
134 sc->sc_gc.gp_pin_write = pl061_gpio_pin_write;
135 sc->sc_gc.gp_pin_ctl = pl061_gpio_pin_ctl;
136
137 const uint32_t cnf = PL061_READ(sc, PL061_GPIOAFSEL_REG);
138
139 for (pin = 0; pin < 8; pin++) {
140 sc->sc_pins[pin].pin_num = pin;
141 /* skip pins in hardware control mode */
142 if ((cnf & __BIT(pin)) != 0)
143 continue;
144 sc->sc_pins[pin].pin_caps =
145 GPIO_PIN_INPUT | GPIO_PIN_OUTPUT |
146 GPIO_PIN_TRISTATE;
147 sc->sc_pins[pin].pin_state =
148 pl061_gpio_pin_read(sc, pin);
149 }
150
151 memset(&gba, 0, sizeof(gba));
152 gba.gba_gc = &sc->sc_gc;
153 gba.gba_pins = sc->sc_pins;
154 gba.gba_npins = 8;
155
156 #if NGPIO > 0
157 (void)config_found_ia(sc->sc_dev, "gpiobus", &gba,
158 gpiobus_print);
159 #endif
160
161 fdtbus_register_gpio_controller(self, faa->faa_phandle,
162 &pl061_gpio_funcs);
163
164 }
165
166 static int
167 pl061_gpio_pin_read(void *priv, int pin)
168 {
169 struct pl061_gpio_softc * const sc = priv;
170
171 const uint32_t v = PL061_READ(sc, PL061_GPIODATA_REG(1<<pin));
172
173 return (v >> pin) & 1;
174 }
175
176 static void
177 pl061_gpio_pin_write(void *priv, int pin, int val)
178 {
179 struct pl061_gpio_softc * const sc = priv;
180
181 PL061_WRITE(sc, PL061_GPIODATA_REG(1 << pin), val << pin);
182 }
183
184 static void
185 pl061_gpio_pin_ctl(void *priv, int pin, int flags)
186 {
187 struct pl061_gpio_softc * const sc = priv;
188 uint32_t v;
189
190 if (flags & GPIO_PIN_INPUT) {
191 v = PL061_READ(sc, PL061_GPIODIR_REG);
192 v &= ~(1 << pin);
193 PL061_WRITE(sc, PL061_GPIODIR_REG, v);
194 } else if (flags & GPIO_PIN_OUTPUT) {
195 v = PL061_READ(sc, PL061_GPIODIR_REG);
196 v |= (1 << pin);
197 PL061_WRITE(sc, PL061_GPIODIR_REG, v);
198 }
199 }
200
201 static void *
202 pl061_gpio_fdt_acquire(device_t dev, const void *data, size_t len, int flags)
203 {
204 struct pl061_gpio_softc * const sc = device_private(dev);
205 struct pl061_gpio_pin *gpin;
206 const u_int *gpio = data;
207
208 if (len != 12)
209 return NULL;
210
211 const u_int pin = be32toh(gpio[1]);
212 const bool actlo = be32toh(gpio[2]) & 1;
213
214 if (pin > 8)
215 return NULL;
216
217 const uint32_t cnf = PL061_READ(sc, PL061_GPIOAFSEL_REG);
218 if ((cnf & __BIT(pin)) != 0)
219 PL061_WRITE(sc, PL061_GPIOAFSEL_REG, cnf & ~__BIT(pin));
220
221 gpin = kmem_zalloc(sizeof(*gpin), KM_SLEEP);
222 gpin->pin_sc = sc;
223 gpin->pin_no = pin;
224 gpin->pin_flags = flags;
225 gpin->pin_actlo = actlo;
226
227 pl061_gpio_pin_ctl(gpin->pin_sc, gpin->pin_no, gpin->pin_flags);
228
229 return gpin;
230 }
231
232 static void
233 pl061_gpio_fdt_release(device_t dev, void *priv)
234 {
235 struct pl061_gpio_pin * const gpin = priv;
236
237 pl061_gpio_pin_ctl(gpin->pin_sc, gpin->pin_no, GPIO_PIN_INPUT);
238 kmem_free(gpin, sizeof(*gpin));
239 }
240
241 static int
242 pl061_gpio_fdt_read(device_t dev, void *priv, bool raw)
243 {
244 struct pl061_gpio_pin * const gpin = priv;
245 int val;
246
247 val = pl061_gpio_pin_read(gpin->pin_sc, gpin->pin_no);
248
249 if (!raw && gpin->pin_actlo)
250 val = !val;
251
252 return val;
253 }
254
255 static void
256 pl061_gpio_fdt_write(device_t dev, void *priv, int val, bool raw)
257 {
258 struct pl061_gpio_pin * const gpin = priv;
259
260 if (!raw && gpin->pin_actlo)
261 val = !val;
262
263 pl061_gpio_pin_write(gpin->pin_sc, gpin->pin_no, val);
264 }
265