1 /*-
2 * Copyright (c) 2016 Jared McNeill <[email protected]>
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
18 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
19 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
20 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
21 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 */
25
26 /*
27 * GPIO controlled regulators
28 */
29
30 #include <sys/cdefs.h>
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/bus.h>
34 #include <sys/rman.h>
35 #include <sys/kernel.h>
36 #include <sys/module.h>
37 #include <sys/gpio.h>
38
39 #include <dev/ofw/ofw_bus.h>
40 #include <dev/ofw/ofw_bus_subr.h>
41
42 #include <dev/gpio/gpiobusvar.h>
43
44 #include <dev/extres/regulator/regulator.h>
45
46 #include "regdev_if.h"
47
48 struct gpioregulator_state {
49 int val;
50 uint32_t mask;
51 };
52
53 struct gpioregulator_init_def {
54 struct regnode_init_def reg_init_def;
55 struct gpiobus_pin *enable_pin;
56 int enable_pin_valid;
57 int startup_delay_us;
58 int nstates;
59 struct gpioregulator_state *states;
60 int npins;
61 struct gpiobus_pin **pins;
62 };
63
64 struct gpioregulator_reg_sc {
65 struct regnode *regnode;
66 device_t base_dev;
67 struct regnode_std_param *param;
68 struct gpioregulator_init_def *def;
69 };
70
71 struct gpioregulator_softc {
72 device_t dev;
73 struct gpioregulator_reg_sc *reg_sc;
74 struct gpioregulator_init_def init_def;
75 };
76
77 static int
gpioregulator_regnode_init(struct regnode * regnode)78 gpioregulator_regnode_init(struct regnode *regnode)
79 {
80 struct gpioregulator_reg_sc *sc;
81 int error, n;
82
83 sc = regnode_get_softc(regnode);
84
85 if (sc->def->enable_pin_valid == 1) {
86 error = gpio_pin_setflags(sc->def->enable_pin, GPIO_PIN_OUTPUT);
87 if (error != 0)
88 return (error);
89 }
90
91 for (n = 0; n < sc->def->npins; n++) {
92 error = gpio_pin_setflags(sc->def->pins[n], GPIO_PIN_OUTPUT);
93 if (error != 0)
94 return (error);
95 }
96
97 return (0);
98 }
99
100 static int
gpioregulator_regnode_enable(struct regnode * regnode,bool enable,int * udelay)101 gpioregulator_regnode_enable(struct regnode *regnode, bool enable, int *udelay)
102 {
103 struct gpioregulator_reg_sc *sc;
104 bool active;
105 int error;
106
107 sc = regnode_get_softc(regnode);
108
109 if (sc->def->enable_pin_valid == 1) {
110 active = enable;
111 if (!sc->param->enable_active_high)
112 active = !active;
113 error = gpio_pin_set_active(sc->def->enable_pin, active);
114 if (error != 0)
115 return (error);
116 }
117
118 *udelay = sc->def->startup_delay_us;
119
120 return (0);
121 }
122
123 static int
gpioregulator_regnode_set_voltage(struct regnode * regnode,int min_uvolt,int max_uvolt,int * udelay)124 gpioregulator_regnode_set_voltage(struct regnode *regnode, int min_uvolt,
125 int max_uvolt, int *udelay)
126 {
127 struct gpioregulator_reg_sc *sc;
128 const struct gpioregulator_state *state;
129 int error, n;
130
131 sc = regnode_get_softc(regnode);
132 state = NULL;
133
134 for (n = 0; n < sc->def->nstates; n++) {
135 if (sc->def->states[n].val >= min_uvolt &&
136 sc->def->states[n].val <= max_uvolt) {
137 state = &sc->def->states[n];
138 break;
139 }
140 }
141 if (state == NULL)
142 return (EINVAL);
143
144 for (n = 0; n < sc->def->npins; n++) {
145 error = gpio_pin_set_active(sc->def->pins[n],
146 (state->mask >> n) & 1);
147 if (error != 0)
148 return (error);
149 }
150
151 *udelay = sc->def->startup_delay_us;
152
153 return (0);
154 }
155
156 static int
gpioregulator_regnode_get_voltage(struct regnode * regnode,int * uvolt)157 gpioregulator_regnode_get_voltage(struct regnode *regnode, int *uvolt)
158 {
159 struct gpioregulator_reg_sc *sc;
160 uint32_t mask;
161 int error, n;
162 bool active;
163
164 sc = regnode_get_softc(regnode);
165 mask = 0;
166
167 for (n = 0; n < sc->def->npins; n++) {
168 error = gpio_pin_is_active(sc->def->pins[n], &active);
169 if (error != 0)
170 return (error);
171 mask |= (active << n);
172 }
173
174 for (n = 0; n < sc->def->nstates; n++) {
175 if (sc->def->states[n].mask == mask) {
176 *uvolt = sc->def->states[n].val;
177 return (0);
178 }
179 }
180
181 return (EIO);
182 }
183
184 static regnode_method_t gpioregulator_regnode_methods[] = {
185 /* Regulator interface */
186 REGNODEMETHOD(regnode_init, gpioregulator_regnode_init),
187 REGNODEMETHOD(regnode_enable, gpioregulator_regnode_enable),
188 REGNODEMETHOD(regnode_set_voltage, gpioregulator_regnode_set_voltage),
189 REGNODEMETHOD(regnode_get_voltage, gpioregulator_regnode_get_voltage),
190 REGNODEMETHOD_END
191 };
192 DEFINE_CLASS_1(gpioregulator_regnode, gpioregulator_regnode_class,
193 gpioregulator_regnode_methods, sizeof(struct gpioregulator_reg_sc),
194 regnode_class);
195
196 static int
gpioregulator_parse_fdt(struct gpioregulator_softc * sc)197 gpioregulator_parse_fdt(struct gpioregulator_softc *sc)
198 {
199 uint32_t *pstates, mask;
200 phandle_t node;
201 ssize_t len;
202 int error, n;
203
204 node = ofw_bus_get_node(sc->dev);
205 pstates = NULL;
206 mask = 0;
207
208 error = regulator_parse_ofw_stdparam(sc->dev, node,
209 &sc->init_def.reg_init_def);
210 if (error != 0)
211 return (error);
212
213 /* "states" property (required) */
214 len = OF_getencprop_alloc_multi(node, "states", sizeof(*pstates),
215 (void **)&pstates);
216 if (len < 2) {
217 device_printf(sc->dev, "invalid 'states' property\n");
218 error = EINVAL;
219 goto done;
220 }
221 sc->init_def.nstates = len / 2;
222 sc->init_def.states = malloc(sc->init_def.nstates *
223 sizeof(*sc->init_def.states), M_DEVBUF, M_WAITOK);
224 for (n = 0; n < sc->init_def.nstates; n++) {
225 sc->init_def.states[n].val = pstates[n * 2 + 0];
226 sc->init_def.states[n].mask = pstates[n * 2 + 1];
227 mask |= sc->init_def.states[n].mask;
228 }
229
230 /* "startup-delay-us" property (optional) */
231 len = OF_getencprop(node, "startup-delay-us",
232 &sc->init_def.startup_delay_us,
233 sizeof(sc->init_def.startup_delay_us));
234 if (len <= 0)
235 sc->init_def.startup_delay_us = 0;
236
237 /* "enable-gpio" property (optional) */
238 error = gpio_pin_get_by_ofw_property(sc->dev, node, "enable-gpio",
239 &sc->init_def.enable_pin);
240 if (error == 0)
241 sc->init_def.enable_pin_valid = 1;
242
243 /* "gpios" property */
244 sc->init_def.npins = 32 - __builtin_clz(mask);
245 sc->init_def.pins = malloc(sc->init_def.npins *
246 sizeof(sc->init_def.pins), M_DEVBUF, M_WAITOK | M_ZERO);
247 for (n = 0; n < sc->init_def.npins; n++) {
248 error = gpio_pin_get_by_ofw_idx(sc->dev, node, n,
249 &sc->init_def.pins[n]);
250 if (error != 0) {
251 device_printf(sc->dev, "cannot get pin %d\n", n);
252 goto done;
253 }
254 }
255
256 done:
257 if (error != 0) {
258 for (n = 0; n < sc->init_def.npins; n++) {
259 if (sc->init_def.pins[n] != NULL)
260 gpio_pin_release(sc->init_def.pins[n]);
261 }
262
263 free(sc->init_def.states, M_DEVBUF);
264 free(sc->init_def.pins, M_DEVBUF);
265
266 }
267 OF_prop_free(pstates);
268
269 return (error);
270 }
271
272 static int
gpioregulator_probe(device_t dev)273 gpioregulator_probe(device_t dev)
274 {
275
276 if (!ofw_bus_is_compatible(dev, "regulator-gpio"))
277 return (ENXIO);
278
279 device_set_desc(dev, "GPIO controlled regulator");
280 return (BUS_PROBE_GENERIC);
281 }
282
283 static int
gpioregulator_attach(device_t dev)284 gpioregulator_attach(device_t dev)
285 {
286 struct gpioregulator_softc *sc;
287 struct regnode *regnode;
288 phandle_t node;
289 int error;
290
291 sc = device_get_softc(dev);
292 sc->dev = dev;
293 node = ofw_bus_get_node(dev);
294
295 error = gpioregulator_parse_fdt(sc);
296 if (error != 0) {
297 device_printf(dev, "cannot parse parameters\n");
298 return (ENXIO);
299 }
300 sc->init_def.reg_init_def.id = 1;
301 sc->init_def.reg_init_def.ofw_node = node;
302
303 regnode = regnode_create(dev, &gpioregulator_regnode_class,
304 &sc->init_def.reg_init_def);
305 if (regnode == NULL) {
306 device_printf(dev, "cannot create regulator\n");
307 return (ENXIO);
308 }
309
310 sc->reg_sc = regnode_get_softc(regnode);
311 sc->reg_sc->regnode = regnode;
312 sc->reg_sc->base_dev = dev;
313 sc->reg_sc->param = regnode_get_stdparam(regnode);
314 sc->reg_sc->def = &sc->init_def;
315
316 regnode_register(regnode);
317
318 return (0);
319 }
320
321
322 static device_method_t gpioregulator_methods[] = {
323 /* Device interface */
324 DEVMETHOD(device_probe, gpioregulator_probe),
325 DEVMETHOD(device_attach, gpioregulator_attach),
326
327 /* Regdev interface */
328 DEVMETHOD(regdev_map, regdev_default_ofw_map),
329
330 DEVMETHOD_END
331 };
332
333 static driver_t gpioregulator_driver = {
334 "gpioregulator",
335 gpioregulator_methods,
336 sizeof(struct gpioregulator_softc),
337 };
338
339 EARLY_DRIVER_MODULE(gpioregulator, simplebus, gpioregulator_driver, 0, 0,
340 BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LAST);
341 MODULE_VERSION(gpioregulator, 1);
342