1 /*-
2 * Copyright (c) 2016 Jared McNeill <jmcneill@invisible.ca>
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/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/rman.h>
34 #include <sys/kernel.h>
35 #include <sys/module.h>
36 #include <sys/gpio.h>
37
38 #include <dev/ofw/ofw_bus.h>
39 #include <dev/ofw/ofw_bus_subr.h>
40
41 #include <dev/gpio/gpiobusvar.h>
42
43 #include <dev/regulator/regulator.h>
44
45 #include "regdev_if.h"
46
47 struct gpioregulator_state {
48 int val;
49 uint32_t mask;
50 };
51
52 struct gpioregulator_init_def {
53 struct regnode_init_def reg_init_def;
54 struct gpiobus_pin *enable_pin;
55 int enable_pin_valid;
56 int startup_delay_us;
57 int nstates;
58 struct gpioregulator_state *states;
59 int npins;
60 struct gpiobus_pin **pins;
61 };
62
63 struct gpioregulator_reg_sc {
64 struct regnode *regnode;
65 device_t base_dev;
66 struct regnode_std_param *param;
67 struct gpioregulator_init_def *def;
68 };
69
70 struct gpioregulator_softc {
71 device_t dev;
72 struct gpioregulator_reg_sc *reg_sc;
73 struct gpioregulator_init_def init_def;
74 };
75
76 static int
gpioregulator_regnode_init(struct regnode * regnode)77 gpioregulator_regnode_init(struct regnode *regnode)
78 {
79 struct gpioregulator_reg_sc *sc;
80 int error, n;
81
82 sc = regnode_get_softc(regnode);
83
84 if (sc->def->enable_pin_valid == 1) {
85 error = gpio_pin_setflags(sc->def->enable_pin, GPIO_PIN_OUTPUT);
86 if (error != 0)
87 return (error);
88 }
89
90 for (n = 0; n < sc->def->npins; n++) {
91 error = gpio_pin_setflags(sc->def->pins[n], GPIO_PIN_OUTPUT);
92 if (error != 0)
93 return (error);
94 }
95
96 return (0);
97 }
98
99 static int
gpioregulator_regnode_enable(struct regnode * regnode,bool enable,int * udelay)100 gpioregulator_regnode_enable(struct regnode *regnode, bool enable, int *udelay)
101 {
102 struct gpioregulator_reg_sc *sc;
103 bool active;
104 int error;
105
106 sc = regnode_get_softc(regnode);
107
108 if (sc->def->enable_pin_valid == 1) {
109 active = enable;
110 if (!sc->param->enable_active_high)
111 active = !active;
112 error = gpio_pin_set_active(sc->def->enable_pin, active);
113 if (error != 0)
114 return (error);
115 }
116
117 *udelay = sc->def->startup_delay_us;
118
119 return (0);
120 }
121
122 static int
gpioregulator_regnode_set_voltage(struct regnode * regnode,int min_uvolt,int max_uvolt,int * udelay)123 gpioregulator_regnode_set_voltage(struct regnode *regnode, int min_uvolt,
124 int max_uvolt, int *udelay)
125 {
126 struct gpioregulator_reg_sc *sc;
127 const struct gpioregulator_state *state;
128 int error, n;
129
130 sc = regnode_get_softc(regnode);
131 state = NULL;
132
133 for (n = 0; n < sc->def->nstates; n++) {
134 if (sc->def->states[n].val >= min_uvolt &&
135 sc->def->states[n].val <= max_uvolt) {
136 state = &sc->def->states[n];
137 break;
138 }
139 }
140 if (state == NULL)
141 return (EINVAL);
142
143 for (n = 0; n < sc->def->npins; n++) {
144 error = gpio_pin_set_active(sc->def->pins[n],
145 (state->mask >> n) & 1);
146 if (error != 0)
147 return (error);
148 }
149
150 *udelay = sc->def->startup_delay_us;
151
152 return (0);
153 }
154
155 static int
gpioregulator_regnode_get_voltage(struct regnode * regnode,int * uvolt)156 gpioregulator_regnode_get_voltage(struct regnode *regnode, int *uvolt)
157 {
158 struct gpioregulator_reg_sc *sc;
159 uint32_t mask;
160 int error, n;
161 bool active;
162
163 sc = regnode_get_softc(regnode);
164 mask = 0;
165
166 for (n = 0; n < sc->def->npins; n++) {
167 error = gpio_pin_is_active(sc->def->pins[n], &active);
168 if (error != 0)
169 return (error);
170 mask |= (active << n);
171 }
172
173 for (n = 0; n < sc->def->nstates; n++) {
174 if (sc->def->states[n].mask == mask) {
175 *uvolt = sc->def->states[n].val;
176 return (0);
177 }
178 }
179
180 return (EIO);
181 }
182
183 static regnode_method_t gpioregulator_regnode_methods[] = {
184 /* Regulator interface */
185 REGNODEMETHOD(regnode_init, gpioregulator_regnode_init),
186 REGNODEMETHOD(regnode_enable, gpioregulator_regnode_enable),
187 REGNODEMETHOD(regnode_set_voltage, gpioregulator_regnode_set_voltage),
188 REGNODEMETHOD(regnode_get_voltage, gpioregulator_regnode_get_voltage),
189 REGNODEMETHOD_END
190 };
191 DEFINE_CLASS_1(gpioregulator_regnode, gpioregulator_regnode_class,
192 gpioregulator_regnode_methods, sizeof(struct gpioregulator_reg_sc),
193 regnode_class);
194
195 static int
gpioregulator_parse_fdt(struct gpioregulator_softc * sc)196 gpioregulator_parse_fdt(struct gpioregulator_softc *sc)
197 {
198 uint32_t *pstates, mask;
199 phandle_t node;
200 ssize_t len;
201 int error, n;
202
203 node = ofw_bus_get_node(sc->dev);
204 pstates = NULL;
205 mask = 0;
206
207 error = regulator_parse_ofw_stdparam(sc->dev, node,
208 &sc->init_def.reg_init_def);
209 if (error != 0)
210 return (error);
211
212 /* "states" property (required) */
213 len = OF_getencprop_alloc_multi(node, "states", sizeof(*pstates),
214 (void **)&pstates);
215 if (len < 2) {
216 device_printf(sc->dev, "invalid 'states' property\n");
217 error = EINVAL;
218 goto done;
219 }
220 sc->init_def.nstates = len / 2;
221 sc->init_def.states = malloc(sc->init_def.nstates *
222 sizeof(*sc->init_def.states), M_DEVBUF, M_WAITOK);
223 for (n = 0; n < sc->init_def.nstates; n++) {
224 sc->init_def.states[n].val = pstates[n * 2 + 0];
225 sc->init_def.states[n].mask = pstates[n * 2 + 1];
226 mask |= sc->init_def.states[n].mask;
227 }
228
229 /* "startup-delay-us" property (optional) */
230 len = OF_getencprop(node, "startup-delay-us",
231 &sc->init_def.startup_delay_us,
232 sizeof(sc->init_def.startup_delay_us));
233 if (len <= 0)
234 sc->init_def.startup_delay_us = 0;
235
236 /* "enable-gpio" property (optional) */
237 error = gpio_pin_get_by_ofw_property(sc->dev, node, "enable-gpio",
238 &sc->init_def.enable_pin);
239 if (error == 0)
240 sc->init_def.enable_pin_valid = 1;
241
242 /* "gpios" property */
243 sc->init_def.npins = 32 - __builtin_clz(mask);
244 sc->init_def.pins = malloc(sc->init_def.npins *
245 sizeof(sc->init_def.pins), M_DEVBUF, M_WAITOK | M_ZERO);
246 for (n = 0; n < sc->init_def.npins; n++) {
247 error = gpio_pin_get_by_ofw_idx(sc->dev, node, n,
248 &sc->init_def.pins[n]);
249 if (error != 0) {
250 device_printf(sc->dev, "cannot get pin %d\n", n);
251 goto done;
252 }
253 }
254
255 done:
256 if (error != 0) {
257 for (n = 0; n < sc->init_def.npins; n++) {
258 if (sc->init_def.pins[n] != NULL)
259 gpio_pin_release(sc->init_def.pins[n]);
260 }
261
262 free(sc->init_def.states, M_DEVBUF);
263 free(sc->init_def.pins, M_DEVBUF);
264
265 }
266 OF_prop_free(pstates);
267
268 return (error);
269 }
270
271 static int
gpioregulator_probe(device_t dev)272 gpioregulator_probe(device_t dev)
273 {
274
275 if (!ofw_bus_is_compatible(dev, "regulator-gpio"))
276 return (ENXIO);
277
278 device_set_desc(dev, "GPIO controlled regulator");
279 return (BUS_PROBE_GENERIC);
280 }
281
282 static int
gpioregulator_attach(device_t dev)283 gpioregulator_attach(device_t dev)
284 {
285 struct gpioregulator_softc *sc;
286 struct regnode *regnode;
287 phandle_t node;
288 int error;
289
290 sc = device_get_softc(dev);
291 sc->dev = dev;
292 node = ofw_bus_get_node(dev);
293
294 error = gpioregulator_parse_fdt(sc);
295 if (error != 0) {
296 device_printf(dev, "cannot parse parameters\n");
297 return (ENXIO);
298 }
299 sc->init_def.reg_init_def.id = 1;
300 sc->init_def.reg_init_def.ofw_node = node;
301
302 regnode = regnode_create(dev, &gpioregulator_regnode_class,
303 &sc->init_def.reg_init_def);
304 if (regnode == NULL) {
305 device_printf(dev, "cannot create regulator\n");
306 return (ENXIO);
307 }
308
309 sc->reg_sc = regnode_get_softc(regnode);
310 sc->reg_sc->regnode = regnode;
311 sc->reg_sc->base_dev = dev;
312 sc->reg_sc->param = regnode_get_stdparam(regnode);
313 sc->reg_sc->def = &sc->init_def;
314
315 regnode_register(regnode);
316
317 return (0);
318 }
319
320
321 static device_method_t gpioregulator_methods[] = {
322 /* Device interface */
323 DEVMETHOD(device_probe, gpioregulator_probe),
324 DEVMETHOD(device_attach, gpioregulator_attach),
325
326 /* Regdev interface */
327 DEVMETHOD(regdev_map, regdev_default_ofw_map),
328
329 DEVMETHOD_END
330 };
331
332 static driver_t gpioregulator_driver = {
333 "gpioregulator",
334 gpioregulator_methods,
335 sizeof(struct gpioregulator_softc),
336 };
337
338 EARLY_DRIVER_MODULE(gpioregulator, simplebus, gpioregulator_driver, 0, 0,
339 BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LAST);
340 MODULE_VERSION(gpioregulator, 1);
341