1 /* $NetBSD: argpio.c,v 1.10 2021/08/07 16:18:58 thorpej Exp $ */
2 
3 /*-
4  * Copyright (c) 2006 Garrett D'Amore
5  * All rights reserved.
6  *
7  * Written by Garrett D'Amore.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. The name of the author may not be used to endorse
18  *    or promote products derived from this software without specific
19  *    prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
22  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
23  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
25  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27  * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
31  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 __KERNEL_RCSID(0, "$NetBSD: argpio.c,v 1.10 2021/08/07 16:18:58 thorpej Exp $");
36 
37 #include <sys/param.h>
38 #include <sys/bus.h>
39 #include <sys/conf.h>
40 #include <sys/device.h>
41 #include <sys/gpio.h>
42 #include <sys/intr.h>
43 #include <sys/kernel.h>
44 #include <sys/types.h>
45 
46 #include <mips/atheros/include/arbusvar.h>
47 
48 #include <dev/gpio/gpiovar.h>
49 #include <dev/sysmon/sysmonvar.h>
50 #include <dev/sysmon/sysmon_taskq.h>
51 
52 #include <mips/atheros/dev/argpioreg.h>
53 
54 /*
55  * General Plan:
56  *
57  * Register GPIOs for all pins that are _not_ associated with the reset
58  * pin.  (Possibly also not the system LED.)
59  */
60 
61 struct argpio_softc {
62           device_t            sc_dev;
63           struct gpio_chipset_tag       sc_gc;
64           gpio_pin_t                    sc_pins[ARGPIO_NPINS];
65           int                           sc_npins;
66           bus_space_tag_t               sc_st;
67           bus_space_handle_t  sc_sh;
68           bus_size_t                    sc_size;
69           int                           sc_caps;
70           struct sysmon_pswitch         sc_resetbtn;
71           void                          *sc_ih;
72           int                           sc_rstpin;
73           int                           sc_ledpin;
74 };
75 
76 static int argpio_match(device_t, cfdata_t, void *);
77 static void argpio_attach(device_t, device_t, void *);
78 static int argpio_intr(void *);
79 static void argpio_reset_pressed(void *);
80 static void argpio_ctl(void *, int, int);
81 static void argpio_write(void *, int, int);
82 static int argpio_read(void *, int);
83 
84 CFATTACH_DECL_NEW(argpio, sizeof (struct argpio_softc), argpio_match,
85     argpio_attach, NULL, NULL);
86 
87 #define   INPUT(pin)          (1 << (pin))                  /* input bit */
88 #define   INTR(pin) (1 << ((pin) + 8))  /* interrupt bit */
89 #define   SERIAL(pin)         (1 << ((pin) + 16)) /* serial mux bit */
90 
91 #define   GETREG(sc, o)                 bus_space_read_4(sc->sc_st, sc->sc_sh, o)
92 #define   PUTREG(sc, o, v)    bus_space_write_4(sc->sc_st, sc->sc_sh, o, v)
93 #define   FLUSH(sc)           bus_space_barrier(sc->sc_st, sc->sc_sh, \
94                                         0, 12, BUS_SPACE_BARRIER_READ|BUS_SPACE_BARRIER_WRITE)
95 
96 int
argpio_match(device_t parent,cfdata_t match,void * aux)97 argpio_match(device_t parent, cfdata_t match, void *aux)
98 {
99           struct arbus_attach_args *aa = aux;
100 
101           return ((strcmp(aa->aa_name, "argpio") == 0) ? 1 : 0);
102 }
103 
104 void
argpio_attach(device_t parent,device_t self,void * aux)105 argpio_attach(device_t parent, device_t self, void *aux)
106 {
107           struct argpio_softc *sc = device_private(self);
108           struct arbus_attach_args *aa = aux;
109           struct gpiobus_attach_args gba;
110           prop_number_t       pn;
111           int i;
112           uint32_t reg;
113 
114           sc->sc_dev = self;
115           sc->sc_st = aa->aa_bst;
116           sc->sc_npins = ARGPIO_NPINS;
117           sc->sc_size = aa->aa_size;
118           sc->sc_ledpin = -1;
119           sc->sc_rstpin = -1;
120 
121           if (bus_space_map(sc->sc_st, aa->aa_addr, sc->sc_size, 0,
122                     &sc->sc_sh) != 0) {
123                     printf(": unable to map registers!\n");
124                     return;
125           }
126 
127           sc->sc_gc.gp_cookie = sc;
128           sc->sc_gc.gp_pin_read = argpio_read;
129           sc->sc_gc.gp_pin_write = argpio_write;
130           sc->sc_gc.gp_pin_ctl = argpio_ctl;
131 
132           aprint_normal(": Atheros AR531X GPIO");
133           pn = prop_dictionary_get(device_properties(sc->sc_dev), "reset-pin");
134           if (pn != NULL) {
135                     KASSERT(prop_object_type(pn) == PROP_TYPE_NUMBER);
136                     sc->sc_rstpin = (int)prop_number_integer_value(pn);
137                     aprint_normal(", reset button pin %d", sc->sc_rstpin);
138           }
139           pn = prop_dictionary_get(device_properties(sc->sc_dev), "sysled-pin");
140           if (pn != NULL) {
141                     KASSERT(prop_object_type(pn) == PROP_TYPE_NUMBER);
142                     sc->sc_ledpin = (int)prop_number_integer_value(pn);
143                     aprint_normal(", system led pin %d", sc->sc_ledpin);
144           }
145 
146           aprint_normal("\n");
147 
148           if (sc->sc_ledpin) {
149                     sc->sc_ih = arbus_intr_establish(aa->aa_cirq, aa->aa_mirq,
150                         argpio_intr, sc);
151                     if (sc->sc_ih == NULL) {
152                               aprint_error_dev(sc->sc_dev,
153                                   "couldn't establish interrupt\n");
154                     }
155           }
156 
157           if (sc->sc_ih) {
158                     sysmon_task_queue_init();
159 
160                     sc->sc_resetbtn.smpsw_name = device_xname(sc->sc_dev);
161                     sc->sc_resetbtn.smpsw_type = PSWITCH_TYPE_RESET;
162                     if (sysmon_pswitch_register(&sc->sc_resetbtn) != 0) {
163                               aprint_normal_dev(sc->sc_dev,
164                                   "unable to register reset button\n");
165                     }
166           }
167 
168           reg = GETREG(sc, GPIO_CR);
169 
170           for (i = 0; i < sc->sc_npins; i++) {
171                     gpio_pin_t          *pp;
172 
173                     pp = &sc->sc_pins[i];
174 
175                     if (i == sc->sc_rstpin) {
176                               /* configure as interrupt for reset */
177                               pp->pin_caps = GPIO_PIN_INPUT;
178                               reg &= ~SERIAL(i);
179                               reg |= INPUT(i);
180                               /* only if we were able to set up the handler, tho' */
181                               if (sc->sc_ih != NULL)
182                                         reg |= INTR(i);
183 
184                     } else if (i == sc->sc_ledpin) {
185                               /* configure as output for LED */
186                               pp->pin_caps = GPIO_PIN_OUTPUT;
187                               reg &= ~SERIAL(i);
188                               reg &= ~INPUT(i);
189                               reg &= ~INTR(i);
190 
191                     } else {
192                               if (reg & SERIAL(i)) {
193                                         /* pin multiplexed with serial bit */
194                                         pp->pin_caps = 0;
195                               } else {
196                                         pp->pin_caps = GPIO_PIN_INPUT |
197                                             GPIO_PIN_OUTPUT;
198                               }
199                     }
200           }
201 
202           PUTREG(sc, GPIO_CR, reg);
203           FLUSH(sc);
204 
205           gba.gba_gc = &sc->sc_gc;
206           gba.gba_pins = sc->sc_pins;
207           gba.gba_npins = sc->sc_npins;
208           config_found(sc->sc_dev, &gba, gpiobus_print, CFARGS_NONE);
209 }
210 
211 void
argpio_ctl(void * arg,int pin,int flags)212 argpio_ctl(void *arg, int pin, int flags)
213 {
214           struct argpio_softc *sc = arg;
215           uint32_t            reg;
216 
217           reg = GETREG(sc, GPIO_CR);
218           if (reg & (SERIAL(pin) | INTR(pin))) {
219                     printf("pin %d cannot be changed!\n", pin);
220                     /* don't allow changes to these bits */
221                     return;
222           }
223           if (flags & GPIO_PIN_INPUT) {
224                     reg |= INPUT(pin);
225           } else {
226                     reg &= ~INPUT(pin);
227           }
228 
229           PUTREG(sc, GPIO_CR, reg);
230           FLUSH(sc);
231 }
232 
233 void
argpio_write(void * arg,int pin,int value)234 argpio_write(void *arg, int pin, int value)
235 {
236           struct argpio_softc *sc = arg;
237           uint32_t            reg;
238 
239           reg = GETREG(sc, GPIO_DO);
240           if (value)
241                     reg &= ~(1 << pin);
242           else
243                     reg |= (1 << pin);
244           PUTREG(sc, GPIO_DO, reg);
245           FLUSH(sc);
246 }
247 
248 int
argpio_read(void * arg,int pin)249 argpio_read(void *arg, int pin)
250 {
251           struct argpio_softc *sc = arg;
252 
253           return ((GETREG(sc, GPIO_DI) & (1 << pin)) ?
254               GPIO_PIN_HIGH : GPIO_PIN_LOW);
255 }
256 
257 void
argpio_reset_pressed(void * arg)258 argpio_reset_pressed(void *arg)
259 {
260           struct argpio_softc *sc = arg;
261           int                           x;
262 
263           sysmon_pswitch_event(&sc->sc_resetbtn, PSWITCH_EVENT_PRESSED);
264 
265           /* reenable the interrupt */
266           x = splhigh();
267           PUTREG(sc, GPIO_CR,
268               GETREG(sc, GPIO_CR) | INTR(sc->sc_rstpin));
269           splx(x);
270 }
271 
272 int
argpio_intr(void * arg)273 argpio_intr(void  *arg)
274 {
275           struct argpio_softc *sc = arg;
276 
277           if (sc->sc_rstpin < 0)
278                     return 0;
279 
280           /* this is an edge triggered interrupt, so disable it for now */
281           PUTREG(sc, GPIO_CR, GETREG(sc, GPIO_CR) & ~INTR(sc->sc_rstpin));
282 
283           /* no other interrupt on this, so we have to claim it */
284           sysmon_task_queue_sched(0, argpio_reset_pressed, sc);
285 
286           return 1;
287 }
288