1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
30  * Driver for PCF8574 / PCF8574A 8-bit I/O expander
31  * with quasi-bidirectional I/O.
87 pcf8574_read(struct pcf8574_softc *sc, uint8_t *val)  in pcf8574_read()  argument
92 	msg.slave = sc->addr;  in pcf8574_read()
95 	msg.buf = val;  in pcf8574_read()
97 	error = iicbus_transfer_excl(sc->dev, &msg, 1, IIC_WAIT);  in pcf8574_read()
102 pcf8574_write(struct pcf8574_softc *sc, uint8_t val)  in pcf8574_write()  argument
107 	msg.slave = sc->addr;  in pcf8574_write()
110 	msg.buf = &val;  in pcf8574_write()
112 	error = iicbus_transfer_excl(sc->dev, &msg, 1, IIC_WAIT);  in pcf8574_write()
121 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)  in pcf8574_probe()
134 	sc->dev = dev;  in pcf8574_attach()
135 	sc->addr = iicbus_get_addr(dev);  in pcf8574_attach()
138 	sc->output_mask = 0;  in pcf8574_attach()
139 	sc->output_state = 0xff;  in pcf8574_attach()
144 	sx_init(&sc->lock, "pcf8574");  in pcf8574_attach()
145 	sc->busdev = gpiobus_attach_bus(dev);  in pcf8574_attach()
146 	if (sc->busdev == NULL) {  in pcf8574_attach()
148 		sx_destroy(&sc->lock);  in pcf8574_attach()
161 	if (sc->busdev != NULL)  in pcf8574_detach()
162 		gpiobus_detach_bus(sc->busdev);  in pcf8574_detach()
164 	sx_destroy(&sc->lock);  in pcf8574_detach()
174 	return (sc->busdev);  in pcf8574_get_bus()
180 	*maxpin = NUM_PINS - 1;  in pcf8574_pin_max()
185 pcf8574_pin_getcaps(device_t dev, uint32_t pin, uint32_t *caps)  in pcf8574_pin_getcaps()  argument
188 	if (pin >= NUM_PINS)  in pcf8574_pin_getcaps()
195 pcf8574_pin_getflags(device_t dev, uint32_t pin, uint32_t *pflags)  in pcf8574_pin_getflags()  argument
198 	uint8_t val, stale;  in pcf8574_pin_getflags()  local
203 	if (pin >= NUM_PINS)  in pcf8574_pin_getflags()
206 	sx_xlock(&sc->lock);  in pcf8574_pin_getflags()
207 	error = pcf8574_read(sc, &val);  in pcf8574_pin_getflags()
211 		sx_xunlock(&sc->lock);  in pcf8574_pin_getflags()
220 	stale = val & sc->output_mask & ~sc->output_state;  in pcf8574_pin_getflags()
221 	sc->output_mask &= ~stale;  in pcf8574_pin_getflags()
222 	sc->output_state |= stale;  in pcf8574_pin_getflags()
224 	if ((sc->output_mask & (1 << pin)) != 0)  in pcf8574_pin_getflags()
228 	sx_xunlock(&sc->lock);  in pcf8574_pin_getflags()
234 pcf8574_pin_setflags(device_t dev, uint32_t pin, uint32_t flags)  in pcf8574_pin_setflags()  argument
238 	uint8_t val;  in pcf8574_pin_setflags()  local
243 	if (pin >= NUM_PINS)  in pcf8574_pin_setflags()
248 	sx_xlock(&sc->lock);  in pcf8574_pin_setflags()
250 		sc->output_mask |= 1 << pin;  in pcf8574_pin_setflags()
253 		sc->output_mask &= ~(1 << pin);  in pcf8574_pin_setflags()
254 		sc->output_state |= 1 << pin;  in pcf8574_pin_setflags()
262 		val = sc->output_state | ~sc->output_mask;  in pcf8574_pin_setflags()
263 		error = pcf8574_write(sc, val);  in pcf8574_pin_setflags()
268 	sx_xunlock(&sc->lock);  in pcf8574_pin_setflags()
274 pcf8574_pin_getname(device_t dev, uint32_t pin, char *name)  in pcf8574_pin_getname()  argument
277 	if (pin >= NUM_PINS)  in pcf8574_pin_getname()
279 	snprintf(name, GPIOMAXNAME, "P%d", pin);  in pcf8574_pin_getname()
284 pcf8574_pin_get(device_t dev, uint32_t pin, unsigned int *on)  in pcf8574_pin_get()  argument
287 	uint8_t val;  in pcf8574_pin_get()  local
292 	sx_xlock(&sc->lock);  in pcf8574_pin_get()
293 	if ((sc->output_mask & (1 << pin)) != 0) {  in pcf8574_pin_get()
294 		*on = (sc->output_state & (1 << pin)) != 0;  in pcf8574_pin_get()
295 		sx_xunlock(&sc->lock);  in pcf8574_pin_get()
299 	error = pcf8574_read(sc, &val);  in pcf8574_pin_get()
302 		sx_xunlock(&sc->lock);  in pcf8574_pin_get()
305 	sx_xunlock(&sc->lock);  in pcf8574_pin_get()
307 	*on = (val & (1 << pin)) != 0;  in pcf8574_pin_get()
312 pcf8574_pin_set(device_t dev, uint32_t pin, unsigned int on)  in pcf8574_pin_set()  argument
315 	uint8_t val;  in pcf8574_pin_set()  local
320 	if (pin >= NUM_PINS)  in pcf8574_pin_set()
323 	sx_xlock(&sc->lock);  in pcf8574_pin_set()
325 	if ((sc->output_mask & (1 << pin)) == 0) {  in pcf8574_pin_set()
326 		sx_xunlock(&sc->lock);  in pcf8574_pin_set()
332 	 * - set all outputs to their recorded state;  in pcf8574_pin_set()
333 	 * - set all inputs to the high state;  in pcf8574_pin_set()
334 	 * - apply the requested change.  in pcf8574_pin_set()
336 	val = sc->output_state | ~sc->output_mask;  in pcf8574_pin_set()
337 	val &= ~(1 << pin);  in pcf8574_pin_set()
338 	val |= (on != 0) << pin;  in pcf8574_pin_set()
340 	error = pcf8574_write(sc, val);  in pcf8574_pin_set()
343 		sx_xunlock(&sc->lock);  in pcf8574_pin_set()
351 	sc->output_state = val;  in pcf8574_pin_set()
352 	sx_xunlock(&sc->lock);  in pcf8574_pin_set()
357 pcf8574_pin_toggle(device_t dev, uint32_t pin)  in pcf8574_pin_toggle()  argument
360 	uint8_t val;  in pcf8574_pin_toggle()  local
365 	if (pin >= NUM_PINS)  in pcf8574_pin_toggle()
368 	sx_xlock(&sc->lock);  in pcf8574_pin_toggle()
370 	if ((sc->output_mask & (1 << pin)) == 0) {  in pcf8574_pin_toggle()
371 		sx_xunlock(&sc->lock);  in pcf8574_pin_toggle()
375 	val = sc->output_state | ~sc->output_mask;  in pcf8574_pin_toggle()
376 	val ^= 1 << pin;  in pcf8574_pin_toggle()
378 	error = pcf8574_write(sc, val);  in pcf8574_pin_toggle()
381 		sx_xunlock(&sc->lock);  in pcf8574_pin_toggle()
385 	sc->output_state = val;  in pcf8574_pin_toggle()
386 	sx_xunlock(&sc->lock);  in pcf8574_pin_toggle()