xref: /freebsd/sys/arm/ti/ti_gpio.c (revision 325151a3)
1 /*-
2  * Copyright (c) 2011 Ben Gray <ben.r.gray@gmail.com>.
3  * Copyright (c) 2014 Luiz Otavio O Souza <loos@FreeBSD.org>.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 /**
29  * Beware that the OMAP4 datasheet(s) lists GPIO banks 1-6, whereas the code
30  * here uses 0-5.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/bus.h>
39 
40 #include <sys/kernel.h>
41 #include <sys/module.h>
42 #include <sys/rman.h>
43 #include <sys/lock.h>
44 #include <sys/mutex.h>
45 #include <sys/gpio.h>
46 #include <sys/interrupt.h>
47 
48 #include <machine/bus.h>
49 #include <machine/resource.h>
50 
51 #include <arm/ti/ti_cpuid.h>
52 #include <arm/ti/ti_gpio.h>
53 #include <arm/ti/ti_scm.h>
54 #include <arm/ti/ti_prcm.h>
55 #include <arm/ti/ti_hwmods.h>
56 
57 #include <dev/fdt/fdt_common.h>
58 #include <dev/gpio/gpiobusvar.h>
59 #include <dev/ofw/openfirm.h>
60 #include <dev/ofw/ofw_bus.h>
61 #include <dev/ofw/ofw_bus_subr.h>
62 
63 #include "gpio_if.h"
64 #include "ti_gpio_if.h"
65 
66 #if !defined(SOC_OMAP4) && !defined(SOC_TI_AM335X)
67 #error "Unknown SoC"
68 #endif
69 
70 /* Register definitions */
71 #define	TI_GPIO_REVISION		0x0000
72 #define	TI_GPIO_SYSCONFIG		0x0010
73 #define	TI_GPIO_IRQSTATUS_RAW_0		0x0024
74 #define	TI_GPIO_IRQSTATUS_RAW_1		0x0028
75 #define	TI_GPIO_IRQSTATUS_0		0x002C
76 #define	TI_GPIO_IRQSTATUS_1		0x0030
77 #define	TI_GPIO_IRQSTATUS_SET_0		0x0034
78 #define	TI_GPIO_IRQSTATUS_SET_1		0x0038
79 #define	TI_GPIO_IRQSTATUS_CLR_0		0x003C
80 #define	TI_GPIO_IRQSTATUS_CLR_1		0x0040
81 #define	TI_GPIO_IRQWAKEN_0		0x0044
82 #define	TI_GPIO_IRQWAKEN_1		0x0048
83 #define	TI_GPIO_SYSSTATUS		0x0114
84 #define	TI_GPIO_IRQSTATUS1		0x0118
85 #define	TI_GPIO_IRQENABLE1		0x011C
86 #define	TI_GPIO_WAKEUPENABLE		0x0120
87 #define	TI_GPIO_IRQSTATUS2		0x0128
88 #define	TI_GPIO_IRQENABLE2		0x012C
89 #define	TI_GPIO_CTRL			0x0130
90 #define	TI_GPIO_OE			0x0134
91 #define	TI_GPIO_DATAIN			0x0138
92 #define	TI_GPIO_DATAOUT			0x013C
93 #define	TI_GPIO_LEVELDETECT0		0x0140
94 #define	TI_GPIO_LEVELDETECT1		0x0144
95 #define	TI_GPIO_RISINGDETECT		0x0148
96 #define	TI_GPIO_FALLINGDETECT		0x014C
97 #define	TI_GPIO_DEBOUNCENABLE		0x0150
98 #define	TI_GPIO_DEBOUNCINGTIME		0x0154
99 #define	TI_GPIO_CLEARWKUPENA		0x0180
100 #define	TI_GPIO_SETWKUENA		0x0184
101 #define	TI_GPIO_CLEARDATAOUT		0x0190
102 #define	TI_GPIO_SETDATAOUT		0x0194
103 
104 /* Other SoC Specific definitions */
105 #define	OMAP4_FIRST_GPIO_BANK		1
106 #define	OMAP4_INTR_PER_BANK		1
107 #define	OMAP4_GPIO_REV			0x50600801
108 #define	AM335X_FIRST_GPIO_BANK		0
109 #define	AM335X_INTR_PER_BANK		2
110 #define	AM335X_GPIO_REV			0x50600801
111 #define	PINS_PER_BANK			32
112 #define	TI_GPIO_MASK(p)			(1U << ((p) % PINS_PER_BANK))
113 
114 static int ti_gpio_detach(device_t);
115 
116 static u_int
117 ti_first_gpio_bank(void)
118 {
119 	switch(ti_chip()) {
120 #ifdef SOC_OMAP4
121 	case CHIP_OMAP_4:
122 		return (OMAP4_FIRST_GPIO_BANK);
123 #endif
124 #ifdef SOC_TI_AM335X
125 	case CHIP_AM335X:
126 		return (AM335X_FIRST_GPIO_BANK);
127 #endif
128 	}
129 	return (0);
130 }
131 
132 static uint32_t
133 ti_gpio_rev(void)
134 {
135 	switch(ti_chip()) {
136 #ifdef SOC_OMAP4
137 	case CHIP_OMAP_4:
138 		return (OMAP4_GPIO_REV);
139 #endif
140 #ifdef SOC_TI_AM335X
141 	case CHIP_AM335X:
142 		return (AM335X_GPIO_REV);
143 #endif
144 	}
145 	return (0);
146 }
147 
148 /**
149  *	Macros for driver mutex locking
150  */
151 #define	TI_GPIO_LOCK(_sc)		mtx_lock_spin(&(_sc)->sc_mtx)
152 #define	TI_GPIO_UNLOCK(_sc)		mtx_unlock_spin(&(_sc)->sc_mtx)
153 #define	TI_GPIO_LOCK_INIT(_sc)		\
154 	mtx_init(&_sc->sc_mtx, device_get_nameunit((_sc)->sc_dev), \
155 	    "ti_gpio", MTX_SPIN)
156 #define	TI_GPIO_LOCK_DESTROY(_sc)	mtx_destroy(&(_sc)->sc_mtx)
157 #define	TI_GPIO_ASSERT_LOCKED(_sc)	mtx_assert(&(_sc)->sc_mtx, MA_OWNED)
158 #define	TI_GPIO_ASSERT_UNLOCKED(_sc)	mtx_assert(&(_sc)->sc_mtx, MA_NOTOWNED)
159 
160 /**
161  *	ti_gpio_read_4 - reads a 32-bit value from one of the GPIO registers
162  *	@sc: GPIO device context
163  *	@bank: The bank to read from
164  *	@off: The offset of a register from the GPIO register address range
165  *
166  *
167  *	RETURNS:
168  *	32-bit value read from the register.
169  */
170 static inline uint32_t
171 ti_gpio_read_4(struct ti_gpio_softc *sc, bus_size_t off)
172 {
173 	return (bus_read_4(sc->sc_mem_res, off));
174 }
175 
176 /**
177  *	ti_gpio_write_4 - writes a 32-bit value to one of the GPIO registers
178  *	@sc: GPIO device context
179  *	@bank: The bank to write to
180  *	@off: The offset of a register from the GPIO register address range
181  *	@val: The value to write into the register
182  *
183  *	RETURNS:
184  *	nothing
185  */
186 static inline void
187 ti_gpio_write_4(struct ti_gpio_softc *sc, bus_size_t off,
188                  uint32_t val)
189 {
190 	bus_write_4(sc->sc_mem_res, off, val);
191 }
192 
193 static inline void
194 ti_gpio_intr_clr(struct ti_gpio_softc *sc, uint32_t mask)
195 {
196 
197 	/* We clear both set of registers. */
198 	ti_gpio_write_4(sc, TI_GPIO_IRQSTATUS_CLR_0, mask);
199 	ti_gpio_write_4(sc, TI_GPIO_IRQSTATUS_CLR_1, mask);
200 }
201 
202 static inline void
203 ti_gpio_intr_set(struct ti_gpio_softc *sc, uint32_t mask)
204 {
205 
206 	/*
207 	 * On OMAP4 we unmask only the MPU interrupt and on AM335x we
208 	 * also activate only the first interrupt.
209 	 */
210 	ti_gpio_write_4(sc, TI_GPIO_IRQSTATUS_SET_0, mask);
211 }
212 
213 static inline void
214 ti_gpio_intr_ack(struct ti_gpio_softc *sc, uint32_t mask)
215 {
216 
217 	/*
218 	 * Acknowledge the interrupt on both registers even if we use only
219 	 * the first one.
220 	 */
221 	ti_gpio_write_4(sc, TI_GPIO_IRQSTATUS_0, mask);
222 	ti_gpio_write_4(sc, TI_GPIO_IRQSTATUS_1, mask);
223 }
224 
225 static inline uint32_t
226 ti_gpio_intr_status(struct ti_gpio_softc *sc)
227 {
228 	uint32_t reg;
229 
230 	/* Get the status from both registers. */
231 	reg = ti_gpio_read_4(sc, TI_GPIO_IRQSTATUS_0);
232 	reg |= ti_gpio_read_4(sc, TI_GPIO_IRQSTATUS_1);
233 
234 	return (reg);
235 }
236 
237 static device_t
238 ti_gpio_get_bus(device_t dev)
239 {
240 	struct ti_gpio_softc *sc;
241 
242 	sc = device_get_softc(dev);
243 
244 	return (sc->sc_busdev);
245 }
246 
247 /**
248  *	ti_gpio_pin_max - Returns the maximum number of GPIO pins
249  *	@dev: gpio device handle
250  *	@maxpin: pointer to a value that upon return will contain the maximum number
251  *	         of pins in the device.
252  *
253  *
254  *	LOCKING:
255  *	No locking required, returns static data.
256  *
257  *	RETURNS:
258  *	Returns 0 on success otherwise an error code
259  */
260 static int
261 ti_gpio_pin_max(device_t dev, int *maxpin)
262 {
263 
264 	*maxpin = PINS_PER_BANK - 1;
265 
266 	return (0);
267 }
268 
269 static int
270 ti_gpio_valid_pin(struct ti_gpio_softc *sc, int pin)
271 {
272 
273 	if (pin >= sc->sc_maxpin || sc->sc_mem_res == NULL)
274 		return (EINVAL);
275 
276 	return (0);
277 }
278 
279 /**
280  *	ti_gpio_pin_getcaps - Gets the capabilties of a given pin
281  *	@dev: gpio device handle
282  *	@pin: the number of the pin
283  *	@caps: pointer to a value that upon return will contain the capabilities
284  *
285  *	Currently all pins have the same capability, notably:
286  *	  - GPIO_PIN_INPUT
287  *	  - GPIO_PIN_OUTPUT
288  *	  - GPIO_PIN_PULLUP
289  *	  - GPIO_PIN_PULLDOWN
290  *
291  *	LOCKING:
292  *	No locking required, returns static data.
293  *
294  *	RETURNS:
295  *	Returns 0 on success otherwise an error code
296  */
297 static int
298 ti_gpio_pin_getcaps(device_t dev, uint32_t pin, uint32_t *caps)
299 {
300 	struct ti_gpio_softc *sc;
301 
302 	sc = device_get_softc(dev);
303 	if (ti_gpio_valid_pin(sc, pin) != 0)
304 		return (EINVAL);
305 
306 	*caps = (GPIO_PIN_INPUT | GPIO_PIN_OUTPUT | GPIO_PIN_PULLUP |
307 	    GPIO_PIN_PULLDOWN);
308 
309 	return (0);
310 }
311 
312 /**
313  *	ti_gpio_pin_getflags - Gets the current flags of a given pin
314  *	@dev: gpio device handle
315  *	@pin: the number of the pin
316  *	@flags: upon return will contain the current flags of the pin
317  *
318  *	Reads the current flags of a given pin, here we actually read the H/W
319  *	registers to determine the flags, rather than storing the value in the
320  *	setflags call.
321  *
322  *	LOCKING:
323  *	Internally locks the context
324  *
325  *	RETURNS:
326  *	Returns 0 on success otherwise an error code
327  */
328 static int
329 ti_gpio_pin_getflags(device_t dev, uint32_t pin, uint32_t *flags)
330 {
331 	struct ti_gpio_softc *sc;
332 
333 	sc = device_get_softc(dev);
334 	if (ti_gpio_valid_pin(sc, pin) != 0)
335 		return (EINVAL);
336 
337 	/* Get the current pin state */
338 	TI_GPIO_LOCK(sc);
339 	TI_GPIO_GET_FLAGS(dev, pin, flags);
340 	TI_GPIO_UNLOCK(sc);
341 
342 	return (0);
343 }
344 
345 /**
346  *	ti_gpio_pin_getname - Gets the name of a given pin
347  *	@dev: gpio device handle
348  *	@pin: the number of the pin
349  *	@name: buffer to put the name in
350  *
351  *	The driver simply calls the pins gpio_n, where 'n' is obviously the number
352  *	of the pin.
353  *
354  *	LOCKING:
355  *	No locking required, returns static data.
356  *
357  *	RETURNS:
358  *	Returns 0 on success otherwise an error code
359  */
360 static int
361 ti_gpio_pin_getname(device_t dev, uint32_t pin, char *name)
362 {
363 	struct ti_gpio_softc *sc;
364 
365 	sc = device_get_softc(dev);
366 	if (ti_gpio_valid_pin(sc, pin) != 0)
367 		return (EINVAL);
368 
369 	/* Set a very simple name */
370 	snprintf(name, GPIOMAXNAME, "gpio_%u", pin);
371 	name[GPIOMAXNAME - 1] = '\0';
372 
373 	return (0);
374 }
375 
376 /**
377  *	ti_gpio_pin_setflags - Sets the flags for a given pin
378  *	@dev: gpio device handle
379  *	@pin: the number of the pin
380  *	@flags: the flags to set
381  *
382  *	The flags of the pin correspond to things like input/output mode, pull-ups,
383  *	pull-downs, etc.  This driver doesn't support all flags, only the following:
384  *	  - GPIO_PIN_INPUT
385  *	  - GPIO_PIN_OUTPUT
386  *	  - GPIO_PIN_PULLUP
387  *	  - GPIO_PIN_PULLDOWN
388  *
389  *	LOCKING:
390  *	Internally locks the context
391  *
392  *	RETURNS:
393  *	Returns 0 on success otherwise an error code
394  */
395 static int
396 ti_gpio_pin_setflags(device_t dev, uint32_t pin, uint32_t flags)
397 {
398 	struct ti_gpio_softc *sc;
399 	uint32_t oe;
400 
401 	sc = device_get_softc(dev);
402 	if (ti_gpio_valid_pin(sc, pin) != 0)
403 		return (EINVAL);
404 
405 	/* Set the GPIO mode and state */
406 	TI_GPIO_LOCK(sc);
407 	if (TI_GPIO_SET_FLAGS(dev, pin, flags) != 0) {
408 		TI_GPIO_UNLOCK(sc);
409 		return (EINVAL);
410 	}
411 
412 	/* If configuring as an output set the "output enable" bit */
413 	oe = ti_gpio_read_4(sc, TI_GPIO_OE);
414 	if (flags & GPIO_PIN_INPUT)
415 		oe |= TI_GPIO_MASK(pin);
416 	else
417 		oe &= ~TI_GPIO_MASK(pin);
418 	ti_gpio_write_4(sc, TI_GPIO_OE, oe);
419 	TI_GPIO_UNLOCK(sc);
420 
421 	return (0);
422 }
423 
424 /**
425  *	ti_gpio_pin_set - Sets the current level on a GPIO pin
426  *	@dev: gpio device handle
427  *	@pin: the number of the pin
428  *	@value: non-zero value will drive the pin high, otherwise the pin is
429  *	        driven low.
430  *
431  *
432  *	LOCKING:
433  *	Internally locks the context
434  *
435  *	RETURNS:
436  *	Returns 0 on success otherwise a error code
437  */
438 static int
439 ti_gpio_pin_set(device_t dev, uint32_t pin, unsigned int value)
440 {
441 	struct ti_gpio_softc *sc;
442 	uint32_t reg;
443 
444 	sc = device_get_softc(dev);
445 	if (ti_gpio_valid_pin(sc, pin) != 0)
446 		return (EINVAL);
447 
448 	TI_GPIO_LOCK(sc);
449 	if (value == GPIO_PIN_LOW)
450 		reg = TI_GPIO_CLEARDATAOUT;
451 	else
452 		reg = TI_GPIO_SETDATAOUT;
453 	ti_gpio_write_4(sc, reg, TI_GPIO_MASK(pin));
454 	TI_GPIO_UNLOCK(sc);
455 
456 	return (0);
457 }
458 
459 /**
460  *	ti_gpio_pin_get - Gets the current level on a GPIO pin
461  *	@dev: gpio device handle
462  *	@pin: the number of the pin
463  *	@value: pointer to a value that upond return will contain the pin value
464  *
465  *	The pin must be configured as an input pin beforehand, otherwise this
466  *	function will fail.
467  *
468  *	LOCKING:
469  *	Internally locks the context
470  *
471  *	RETURNS:
472  *	Returns 0 on success otherwise a error code
473  */
474 static int
475 ti_gpio_pin_get(device_t dev, uint32_t pin, unsigned int *value)
476 {
477 	struct ti_gpio_softc *sc;
478 	uint32_t oe, reg, val;
479 
480 	sc = device_get_softc(dev);
481 	if (ti_gpio_valid_pin(sc, pin) != 0)
482 		return (EINVAL);
483 
484 	/*
485 	 * Return data from output latch when set as output and from the
486 	 * input register otherwise.
487 	 */
488 	TI_GPIO_LOCK(sc);
489 	oe = ti_gpio_read_4(sc, TI_GPIO_OE);
490 	if (oe & TI_GPIO_MASK(pin))
491 		reg = TI_GPIO_DATAIN;
492 	else
493 		reg = TI_GPIO_DATAOUT;
494 	val = ti_gpio_read_4(sc, reg);
495 	*value = (val & TI_GPIO_MASK(pin)) ? 1 : 0;
496 	TI_GPIO_UNLOCK(sc);
497 
498 	return (0);
499 }
500 
501 /**
502  *	ti_gpio_pin_toggle - Toggles a given GPIO pin
503  *	@dev: gpio device handle
504  *	@pin: the number of the pin
505  *
506  *
507  *	LOCKING:
508  *	Internally locks the context
509  *
510  *	RETURNS:
511  *	Returns 0 on success otherwise a error code
512  */
513 static int
514 ti_gpio_pin_toggle(device_t dev, uint32_t pin)
515 {
516 	struct ti_gpio_softc *sc;
517 	uint32_t reg, val;
518 
519 	sc = device_get_softc(dev);
520 	if (ti_gpio_valid_pin(sc, pin) != 0)
521 		return (EINVAL);
522 
523 	/* Toggle the pin */
524 	TI_GPIO_LOCK(sc);
525 	val = ti_gpio_read_4(sc, TI_GPIO_DATAOUT);
526 	if (val & TI_GPIO_MASK(pin))
527 		reg = TI_GPIO_CLEARDATAOUT;
528 	else
529 		reg = TI_GPIO_SETDATAOUT;
530 	ti_gpio_write_4(sc, reg, TI_GPIO_MASK(pin));
531 	TI_GPIO_UNLOCK(sc);
532 
533 	return (0);
534 }
535 
536 /**
537  *	ti_gpio_intr - ISR for all GPIO modules
538  *	@arg: the soft context pointer
539  *
540  *	LOCKING:
541  *	Internally locks the context
542  *
543  */
544 static int
545 ti_gpio_intr(void *arg)
546 {
547 	int bank_last, irq;
548 	struct intr_event *event;
549 	struct ti_gpio_softc *sc;
550 	uint32_t reg;
551 
552 	sc = (struct ti_gpio_softc *)arg;
553 	bank_last = -1;
554 	reg = 0; /* squelch bogus gcc warning */
555 	reg = ti_gpio_intr_status(sc);
556 	for (irq = 0; irq < sc->sc_maxpin; irq++) {
557 		if ((reg & TI_GPIO_MASK(irq)) == 0)
558 			continue;
559 		event = sc->sc_events[irq];
560 		if (event != NULL && !TAILQ_EMPTY(&event->ie_handlers))
561 			intr_event_handle(event, NULL);
562 		else
563 			device_printf(sc->sc_dev, "Stray IRQ %d\n", irq);
564 		/* Ack the IRQ Status bit. */
565 		ti_gpio_intr_ack(sc, TI_GPIO_MASK(irq));
566 	}
567 
568 	return (FILTER_HANDLED);
569 }
570 
571 static int
572 ti_gpio_bank_init(device_t dev)
573 {
574 	int pin;
575 	struct ti_gpio_softc *sc;
576 	uint32_t flags, reg_oe, reg_set, rev;
577 	clk_ident_t clk;
578 
579 	sc = device_get_softc(dev);
580 
581 	/* Enable the interface and functional clocks for the module. */
582 	clk = ti_hwmods_get_clock(dev);
583 	if (clk == INVALID_CLK_IDENT) {
584 		device_printf(dev, "failed to get device id based on ti,hwmods\n");
585 		return (EINVAL);
586 	}
587 
588 	sc->sc_bank = clk - GPIO1_CLK + ti_first_gpio_bank();
589 	ti_prcm_clk_enable(clk);
590 
591 	/*
592 	 * Read the revision number of the module.  TI don't publish the
593 	 * actual revision numbers, so instead the values have been
594 	 * determined by experimentation.
595 	 */
596 	rev = ti_gpio_read_4(sc, TI_GPIO_REVISION);
597 
598 	/* Check the revision. */
599 	if (rev != ti_gpio_rev()) {
600 		device_printf(dev, "Warning: could not determine the revision "
601 		    "of GPIO module (revision:0x%08x)\n", rev);
602 		return (EINVAL);
603 	}
604 
605 	/* Disable interrupts for all pins. */
606 	ti_gpio_intr_clr(sc, 0xffffffff);
607 
608 	/* Init OE register based on pads configuration. */
609 	reg_oe = 0xffffffff;
610 	reg_set = 0;
611 	for (pin = 0; pin < PINS_PER_BANK; pin++) {
612 		TI_GPIO_GET_FLAGS(dev, pin, &flags);
613 		if (flags & GPIO_PIN_OUTPUT) {
614 			reg_oe &= ~(1UL << pin);
615 			if (flags & GPIO_PIN_PULLUP)
616 				reg_set |= (1UL << pin);
617 		}
618 	}
619 	ti_gpio_write_4(sc, TI_GPIO_OE, reg_oe);
620 	if (reg_set)
621 		ti_gpio_write_4(sc, TI_GPIO_SETDATAOUT, reg_set);
622 
623 	return (0);
624 }
625 
626 /**
627  *	ti_gpio_attach - attach function for the driver
628  *	@dev: gpio device handle
629  *
630  *	Allocates and sets up the driver context for all GPIO banks.  This function
631  *	expects the memory ranges and IRQs to already be allocated to the driver.
632  *
633  *	LOCKING:
634  *	None
635  *
636  *	RETURNS:
637  *	Always returns 0
638  */
639 static int
640 ti_gpio_attach(device_t dev)
641 {
642 	struct ti_gpio_softc *sc;
643 	unsigned int i;
644 	int err;
645 
646 	sc = device_get_softc(dev);
647 	sc->sc_dev = dev;
648 	TI_GPIO_LOCK_INIT(sc);
649 	ti_gpio_pin_max(dev, &sc->sc_maxpin);
650 	sc->sc_maxpin++;
651 
652 	sc->sc_mem_rid = 0;
653 	sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
654 	    &sc->sc_mem_rid, RF_ACTIVE);
655 	if (!sc->sc_mem_res) {
656 		device_printf(dev, "Error: could not allocate mem resources\n");
657 		ti_gpio_detach(dev);
658 		return (ENXIO);
659 	}
660 
661 	sc->sc_irq_rid = 0;
662 	sc->sc_irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ,
663 	    &sc->sc_irq_rid, RF_ACTIVE);
664 	if (!sc->sc_irq_res) {
665 		device_printf(dev, "Error: could not allocate irq resources\n");
666 		ti_gpio_detach(dev);
667 		return (ENXIO);
668 	}
669 
670 	/*
671 	 * Register our interrupt filter for each of the IRQ resources.
672 	 */
673 	if (bus_setup_intr(dev, sc->sc_irq_res,
674 	    INTR_TYPE_MISC | INTR_MPSAFE, ti_gpio_intr, NULL, sc,
675 	    &sc->sc_irq_hdl) != 0) {
676 		device_printf(dev,
677 		    "WARNING: unable to register interrupt filter\n");
678 		ti_gpio_detach(dev);
679 		return (ENXIO);
680 	}
681 
682 	/*
683 	 * Initialize the interrupt settings.  The default is active-low
684 	 * interrupts.
685 	 */
686 	sc->sc_irq_trigger = malloc(
687 	    sizeof(*sc->sc_irq_trigger) * sc->sc_maxpin,
688 	    M_DEVBUF, M_WAITOK | M_ZERO);
689 	sc->sc_irq_polarity = malloc(
690 	    sizeof(*sc->sc_irq_polarity) * sc->sc_maxpin,
691 	    M_DEVBUF, M_WAITOK | M_ZERO);
692 	for (i = 0; i < sc->sc_maxpin; i++) {
693 		sc->sc_irq_trigger[i] = INTR_TRIGGER_LEVEL;
694 		sc->sc_irq_polarity[i] = INTR_POLARITY_LOW;
695 	}
696 
697 	sc->sc_events = malloc(sizeof(struct intr_event *) * sc->sc_maxpin,
698 	    M_DEVBUF, M_WAITOK | M_ZERO);
699 
700 	sc->sc_mask_args = malloc(sizeof(struct ti_gpio_mask_arg) * sc->sc_maxpin,
701 	    M_DEVBUF, M_WAITOK | M_ZERO);
702 
703 	/* We need to go through each block and ensure the clocks are running and
704 	 * the module is enabled.  It might be better to do this only when the
705 	 * pins are configured which would result in less power used if the GPIO
706 	 * pins weren't used ...
707 	 */
708 	if (sc->sc_mem_res != NULL) {
709 		/* Initialize the GPIO module. */
710 		err = ti_gpio_bank_init(dev);
711 		if (err != 0) {
712 			ti_gpio_detach(dev);
713 			return (err);
714 		}
715 	}
716 
717 	sc->sc_busdev = gpiobus_attach_bus(dev);
718 	if (sc->sc_busdev == NULL) {
719 		ti_gpio_detach(dev);
720 		return (ENXIO);
721 	}
722 
723 	return (0);
724 }
725 
726 /**
727  *	ti_gpio_detach - detach function for the driver
728  *	@dev: scm device handle
729  *
730  *	Allocates and sets up the driver context, this simply entails creating a
731  *	bus mappings for the SCM register set.
732  *
733  *	LOCKING:
734  *	None
735  *
736  *	RETURNS:
737  *	Always returns 0
738  */
739 static int
740 ti_gpio_detach(device_t dev)
741 {
742 	struct ti_gpio_softc *sc = device_get_softc(dev);
743 
744 	KASSERT(mtx_initialized(&sc->sc_mtx), ("gpio mutex not initialized"));
745 
746 	/* Disable all interrupts */
747 	if (sc->sc_mem_res != NULL)
748 		ti_gpio_intr_clr(sc, 0xffffffff);
749 	gpiobus_detach_bus(dev);
750 	if (sc->sc_events)
751 		free(sc->sc_events, M_DEVBUF);
752 	if (sc->sc_mask_args)
753 		free(sc->sc_mask_args, M_DEVBUF);
754 	if (sc->sc_irq_polarity)
755 		free(sc->sc_irq_polarity, M_DEVBUF);
756 	if (sc->sc_irq_trigger)
757 		free(sc->sc_irq_trigger, M_DEVBUF);
758 	/* Release the memory and IRQ resources. */
759 	if (sc->sc_irq_hdl) {
760 		bus_teardown_intr(dev, sc->sc_irq_res,
761 		    sc->sc_irq_hdl);
762 	}
763 	bus_release_resource(dev, SYS_RES_IRQ, sc->sc_irq_rid,
764 	    sc->sc_irq_res);
765 	bus_release_resource(dev, SYS_RES_MEMORY, sc->sc_mem_rid,
766 	    sc->sc_mem_res);
767 	TI_GPIO_LOCK_DESTROY(sc);
768 
769 	return (0);
770 }
771 
772 static uint32_t
773 ti_gpio_intr_reg(struct ti_gpio_softc *sc, int irq)
774 {
775 
776 	if (ti_gpio_valid_pin(sc, irq) != 0)
777 		return (0);
778 
779 	if (sc->sc_irq_trigger[irq] == INTR_TRIGGER_LEVEL) {
780 		if (sc->sc_irq_polarity[irq] == INTR_POLARITY_LOW)
781 			return (TI_GPIO_LEVELDETECT0);
782 		else if (sc->sc_irq_polarity[irq] == INTR_POLARITY_HIGH)
783 			return (TI_GPIO_LEVELDETECT1);
784 	} else if (sc->sc_irq_trigger[irq] == INTR_TRIGGER_EDGE) {
785 		if (sc->sc_irq_polarity[irq] == INTR_POLARITY_LOW)
786 			return (TI_GPIO_FALLINGDETECT);
787 		else if (sc->sc_irq_polarity[irq] == INTR_POLARITY_HIGH)
788 			return (TI_GPIO_RISINGDETECT);
789 	}
790 
791 	return (0);
792 }
793 
794 static void
795 ti_gpio_mask_irq_internal(struct ti_gpio_softc *sc, int irq)
796 {
797 	uint32_t reg, val;
798 
799 	if (ti_gpio_valid_pin(sc, irq) != 0)
800 		return;
801 
802 	TI_GPIO_LOCK(sc);
803 	ti_gpio_intr_clr(sc, TI_GPIO_MASK(irq));
804 	reg = ti_gpio_intr_reg(sc, irq);
805 	if (reg != 0) {
806 		val = ti_gpio_read_4(sc, reg);
807 		val &= ~TI_GPIO_MASK(irq);
808 		ti_gpio_write_4(sc, reg, val);
809 	}
810 	TI_GPIO_UNLOCK(sc);
811 }
812 
813 static void
814 ti_gpio_unmask_irq_internal(struct ti_gpio_softc *sc, int irq)
815 {
816 	uint32_t reg, val;
817 
818 	if (ti_gpio_valid_pin(sc, irq) != 0)
819 		return;
820 
821 	TI_GPIO_LOCK(sc);
822 	reg = ti_gpio_intr_reg(sc, irq);
823 	if (reg != 0) {
824 		val = ti_gpio_read_4(sc, reg);
825 		val |= TI_GPIO_MASK(irq);
826 		ti_gpio_write_4(sc, reg, val);
827 		ti_gpio_intr_set(sc, TI_GPIO_MASK(irq));
828 	}
829 	TI_GPIO_UNLOCK(sc);
830 }
831 
832 static void
833 ti_gpio_mask_irq(void *source)
834 {
835 	struct ti_gpio_mask_arg *arg = source;
836 
837 	ti_gpio_mask_irq_internal(arg->softc, arg->pin);
838 }
839 
840 static void
841 ti_gpio_unmask_irq(void *source)
842 {
843 	struct ti_gpio_mask_arg *arg = source;
844 
845 	ti_gpio_unmask_irq_internal(arg->softc, arg->pin);
846 }
847 
848 static int
849 ti_gpio_activate_resource(device_t dev, device_t child, int type, int rid,
850 	struct resource *res)
851 {
852 	struct ti_gpio_mask_arg mask_arg;
853 
854 	if (type != SYS_RES_IRQ)
855 		return (ENXIO);
856 
857 	/* Unmask the interrupt. */
858 	mask_arg.pin = rman_get_start(res);
859 	mask_arg.softc = device_get_softc(dev);
860 
861 	ti_gpio_unmask_irq((void *)&mask_arg);
862 
863 	return (0);
864 }
865 
866 static int
867 ti_gpio_deactivate_resource(device_t dev, device_t child, int type, int rid,
868 	struct resource *res)
869 {
870 	int pin;
871 
872 	if (type != SYS_RES_IRQ)
873 		return (ENXIO);
874 
875 	/* Mask the interrupt. */
876 	pin = rman_get_start(res);
877 	ti_gpio_mask_irq((void *)(uintptr_t)pin);
878 
879 	return (0);
880 }
881 
882 static int
883 ti_gpio_config_intr(device_t dev, int irq, enum intr_trigger trig,
884 	enum intr_polarity pol)
885 {
886 	struct ti_gpio_softc *sc;
887 	uint32_t oldreg, reg, val;
888 
889 	sc = device_get_softc(dev);
890 	if (ti_gpio_valid_pin(sc, irq) != 0)
891 		return (EINVAL);
892 
893 	/* There is no standard trigger or polarity. */
894 	if (trig == INTR_TRIGGER_CONFORM || pol == INTR_POLARITY_CONFORM)
895 		return (EINVAL);
896 
897 	TI_GPIO_LOCK(sc);
898 	/*
899 	 * TRM recommends add the new event before remove the old one to
900 	 * avoid losing interrupts.
901 	 */
902 	oldreg = ti_gpio_intr_reg(sc, irq);
903 	sc->sc_irq_trigger[irq] = trig;
904 	sc->sc_irq_polarity[irq] = pol;
905 	reg = ti_gpio_intr_reg(sc, irq);
906 	if (reg != 0) {
907 		/* Apply the new settings. */
908 		val = ti_gpio_read_4(sc, reg);
909 		val |= TI_GPIO_MASK(irq);
910 		ti_gpio_write_4(sc, reg, val);
911 	}
912 	if (reg != oldreg && oldreg != 0) {
913 		/* Remove the old settings. */
914 		val = ti_gpio_read_4(sc, oldreg);
915 		val &= ~TI_GPIO_MASK(irq);
916 		ti_gpio_write_4(sc, oldreg, val);
917 	}
918 	TI_GPIO_UNLOCK(sc);
919 
920 	return (0);
921 }
922 
923 static int
924 ti_gpio_setup_intr(device_t dev, device_t child, struct resource *ires,
925 	int flags, driver_filter_t *filt, driver_intr_t *handler,
926 	void *arg, void **cookiep)
927 {
928 	struct ti_gpio_softc *sc;
929 	struct intr_event *event;
930 	int pin, error;
931 
932 	sc = device_get_softc(dev);
933 	pin = rman_get_start(ires);
934 	if (ti_gpio_valid_pin(sc, pin) != 0)
935 		panic("%s: bad pin %d", __func__, pin);
936 
937 	event = sc->sc_events[pin];
938 	if (event == NULL) {
939 		sc->sc_mask_args[pin].softc = sc;
940 		sc->sc_mask_args[pin].pin = pin;
941 		error = intr_event_create(&event, (void *)&sc->sc_mask_args[pin], 0,
942 		    pin, ti_gpio_mask_irq, ti_gpio_unmask_irq, NULL, NULL,
943 		    "gpio%d pin%d:", device_get_unit(dev), pin);
944 		if (error != 0)
945 			return (error);
946 		sc->sc_events[pin] = event;
947 	}
948 	intr_event_add_handler(event, device_get_nameunit(child), filt,
949 	    handler, arg, intr_priority(flags), flags, cookiep);
950 
951 	return (0);
952 }
953 
954 static int
955 ti_gpio_teardown_intr(device_t dev, device_t child, struct resource *ires,
956 	void *cookie)
957 {
958 	struct ti_gpio_softc *sc;
959 	int pin, err;
960 
961 	sc = device_get_softc(dev);
962 	pin = rman_get_start(ires);
963 	if (ti_gpio_valid_pin(sc, pin) != 0)
964 		panic("%s: bad pin %d", __func__, pin);
965 	if (sc->sc_events[pin] == NULL)
966 		panic("Trying to teardown unoccupied IRQ");
967 	err = intr_event_remove_handler(cookie);
968 	if (!err)
969 		sc->sc_events[pin] = NULL;
970 
971 	return (err);
972 }
973 
974 static phandle_t
975 ti_gpio_get_node(device_t bus, device_t dev)
976 {
977 
978 	/* We only have one child, the GPIO bus, which needs our own node. */
979 	return (ofw_bus_get_node(bus));
980 }
981 
982 static device_method_t ti_gpio_methods[] = {
983 	DEVMETHOD(device_attach, ti_gpio_attach),
984 	DEVMETHOD(device_detach, ti_gpio_detach),
985 
986 	/* GPIO protocol */
987 	DEVMETHOD(gpio_get_bus, ti_gpio_get_bus),
988 	DEVMETHOD(gpio_pin_max, ti_gpio_pin_max),
989 	DEVMETHOD(gpio_pin_getname, ti_gpio_pin_getname),
990 	DEVMETHOD(gpio_pin_getflags, ti_gpio_pin_getflags),
991 	DEVMETHOD(gpio_pin_getcaps, ti_gpio_pin_getcaps),
992 	DEVMETHOD(gpio_pin_setflags, ti_gpio_pin_setflags),
993 	DEVMETHOD(gpio_pin_get, ti_gpio_pin_get),
994 	DEVMETHOD(gpio_pin_set, ti_gpio_pin_set),
995 	DEVMETHOD(gpio_pin_toggle, ti_gpio_pin_toggle),
996 
997 	/* Bus interface */
998 	DEVMETHOD(bus_activate_resource, ti_gpio_activate_resource),
999 	DEVMETHOD(bus_deactivate_resource, ti_gpio_deactivate_resource),
1000 	DEVMETHOD(bus_config_intr, ti_gpio_config_intr),
1001 	DEVMETHOD(bus_setup_intr, ti_gpio_setup_intr),
1002 	DEVMETHOD(bus_teardown_intr, ti_gpio_teardown_intr),
1003 
1004 	/* ofw_bus interface */
1005 	DEVMETHOD(ofw_bus_get_node, ti_gpio_get_node),
1006 
1007 	{0, 0},
1008 };
1009 
1010 driver_t ti_gpio_driver = {
1011 	"gpio",
1012 	ti_gpio_methods,
1013 	sizeof(struct ti_gpio_softc),
1014 };
1015