xref: /freebsd/sys/arm/ti/ti_gpio.c (revision 617aa98c6c25406d90089351dbdf69d3a205f49d)
1 /*-
2  * Copyright (c) 2011
3  *	Ben Gray <ben.r.gray@gmail.com>.
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  *	Very simple GPIO (general purpose IO) driver module for TI OMAP SoC's.
30  *
31  *	Currently this driver only does the basics, get a value on a pin & set a
32  *	value on a pin. Hopefully over time I'll expand this to be a bit more generic
33  *	and support interrupts and other various bits on the SoC can do ... in the
34  *	meantime this is all you get.
35  *
36  *	Beware the OMA datasheet(s) lists GPIO banks 1-6, whereas I've used 0-5 here
37  *	in the code.
38  *
39  *
40  */
41 
42 #include <sys/cdefs.h>
43 __FBSDID("$FreeBSD$");
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/bus.h>
48 
49 #include <sys/kernel.h>
50 #include <sys/module.h>
51 #include <sys/rman.h>
52 #include <sys/lock.h>
53 #include <sys/mutex.h>
54 #include <sys/gpio.h>
55 
56 #include <machine/bus.h>
57 #include <machine/resource.h>
58 
59 #include <arm/ti/ti_cpuid.h>
60 #include <arm/ti/ti_scm.h>
61 #include <arm/ti/ti_prcm.h>
62 
63 #include <dev/fdt/fdt_common.h>
64 #include <dev/ofw/openfirm.h>
65 #include <dev/ofw/ofw_bus.h>
66 #include <dev/ofw/ofw_bus_subr.h>
67 
68 #include "gpio_if.h"
69 
70 /* Register definitions */
71 #define	TI_GPIO_REVISION		0x0000
72 #define	TI_GPIO_SYSCONFIG		0x0010
73 #if defined(SOC_OMAP4) || defined(SOC_TI_AM335X)
74 #define	TI_GPIO_IRQSTATUS_RAW_0		0x0024
75 #define	TI_GPIO_IRQSTATUS_RAW_1		0x0028
76 #define	TI_GPIO_IRQSTATUS_0		0x002C
77 #define	TI_GPIO_IRQSTATUS_1		0x0030
78 #define	TI_GPIO_IRQSTATUS_SET_0		0x0034
79 #define	TI_GPIO_IRQSTATUS_SET_1		0x0038
80 #define	TI_GPIO_IRQSTATUS_CLR_0		0x003C
81 #define	TI_GPIO_IRQSTATUS_CLR_1		0x0040
82 #define	TI_GPIO_IRQWAKEN_0		0x0044
83 #define	TI_GPIO_IRQWAKEN_1		0x0048
84 #define	TI_GPIO_SYSSTATUS		0x0114
85 #define	TI_GPIO_IRQSTATUS1		0x0118
86 #define	TI_GPIO_IRQENABLE1		0x011C
87 #define	TI_GPIO_WAKEUPENABLE		0x0120
88 #define	TI_GPIO_IRQSTATUS2		0x0128
89 #define	TI_GPIO_IRQENABLE2		0x012C
90 #define	TI_GPIO_CTRL			0x0130
91 #define	TI_GPIO_OE			0x0134
92 #define	TI_GPIO_DATAIN			0x0138
93 #define	TI_GPIO_DATAOUT			0x013C
94 #define	TI_GPIO_LEVELDETECT0		0x0140
95 #define	TI_GPIO_LEVELDETECT1		0x0144
96 #define	TI_GPIO_RISINGDETECT		0x0148
97 #define	TI_GPIO_FALLINGDETECT		0x014C
98 #define	TI_GPIO_DEBOUNCENABLE		0x0150
99 #define	TI_GPIO_DEBOUNCINGTIME		0x0154
100 #define	TI_GPIO_CLEARWKUPENA		0x0180
101 #define	TI_GPIO_SETWKUENA		0x0184
102 #define	TI_GPIO_CLEARDATAOUT		0x0190
103 #define	TI_GPIO_SETDATAOUT		0x0194
104 #else
105 #error "Unknown SoC"
106 #endif
107 
108 /* Other SoC Specific definitions */
109 #define	OMAP4_MAX_GPIO_BANKS		6
110 #define	OMAP4_FIRST_GPIO_BANK		1
111 #define	OMAP4_INTR_PER_BANK		1
112 #define	OMAP4_GPIO_REV			0x50600801
113 #define	AM335X_MAX_GPIO_BANKS		4
114 #define	AM335X_FIRST_GPIO_BANK		0
115 #define	AM335X_INTR_PER_BANK		2
116 #define	AM335X_GPIO_REV			0x50600801
117 #define	PINS_PER_BANK			32
118 #define	MAX_GPIO_BANKS			6
119 /* Maximum GPIOS possible, max of *_MAX_GPIO_BANKS * *_INTR_PER_BANK */
120 #define	MAX_GPIO_INTRS			8
121 
122 static u_int
123 ti_max_gpio_banks(void)
124 {
125 	switch(ti_chip()) {
126 #ifdef SOC_OMAP4
127 	case CHIP_OMAP_4:
128 		return (OMAP4_MAX_GPIO_BANKS);
129 #endif
130 #ifdef SOC_TI_AM335X
131 	case CHIP_AM335X:
132 		return (AM335X_MAX_GPIO_BANKS);
133 #endif
134 	}
135 	return (0);
136 }
137 
138 static u_int
139 ti_max_gpio_intrs(void)
140 {
141 	switch(ti_chip()) {
142 #ifdef SOC_OMAP4
143 	case CHIP_OMAP_4:
144 		return (OMAP4_MAX_GPIO_BANKS * OMAP4_INTR_PER_BANK);
145 #endif
146 #ifdef SOC_TI_AM335X
147 	case CHIP_AM335X:
148 		return (AM335X_MAX_GPIO_BANKS * AM335X_INTR_PER_BANK);
149 #endif
150 	}
151 	return (0);
152 }
153 
154 static u_int
155 ti_first_gpio_bank(void)
156 {
157 	switch(ti_chip()) {
158 #ifdef SOC_OMAP4
159 	case CHIP_OMAP_4:
160 		return (OMAP4_FIRST_GPIO_BANK);
161 #endif
162 #ifdef SOC_TI_AM335X
163 	case CHIP_AM335X:
164 		return (AM335X_FIRST_GPIO_BANK);
165 #endif
166 	}
167 	return (0);
168 }
169 
170 static uint32_t
171 ti_gpio_rev(void)
172 {
173 	switch(ti_chip()) {
174 #ifdef SOC_OMAP4
175 	case CHIP_OMAP_4:
176 		return (OMAP4_GPIO_REV);
177 #endif
178 #ifdef SOC_TI_AM335X
179 	case CHIP_AM335X:
180 		return (AM335X_GPIO_REV);
181 #endif
182 	}
183 	return (0);
184 }
185 
186 /**
187  *	ti_gpio_mem_spec - Resource specification used when allocating resources
188  *	ti_gpio_irq_spec - Resource specification used when allocating resources
189  *
190  *	This driver module can have up to six independent memory regions, each
191  *	region typically controls 32 GPIO pins.
192  *
193  *	On OMAP3 and OMAP4 there is only one physical interrupt line per bank,
194  *	but there are two set of registers which control the interrupt delivery
195  *	to internal subsystems.  The first set of registers control the
196  *	interrupts delivery to the MPU and the second set control the
197  *	interrupts delivery to the DSP.
198  *
199  *	On AM335x there are two physical interrupt lines for each GPIO module.
200  *	Each interrupt line is controlled by a set of registers.
201  */
202 static struct resource_spec ti_gpio_mem_spec[] = {
203 	{ SYS_RES_MEMORY,   0,  RF_ACTIVE },
204 	{ SYS_RES_MEMORY,   1,  RF_ACTIVE | RF_OPTIONAL },
205 	{ SYS_RES_MEMORY,   2,  RF_ACTIVE | RF_OPTIONAL },
206 	{ SYS_RES_MEMORY,   3,  RF_ACTIVE | RF_OPTIONAL },
207 #if !defined(SOC_TI_AM335X)
208 	{ SYS_RES_MEMORY,   4,  RF_ACTIVE | RF_OPTIONAL },
209 	{ SYS_RES_MEMORY,   5,  RF_ACTIVE | RF_OPTIONAL },
210 #endif
211 	{ -1,               0,  0 }
212 };
213 static struct resource_spec ti_gpio_irq_spec[] = {
214 	{ SYS_RES_IRQ,      0,  RF_ACTIVE },
215 	{ SYS_RES_IRQ,      1,  RF_ACTIVE | RF_OPTIONAL },
216 	{ SYS_RES_IRQ,      2,  RF_ACTIVE | RF_OPTIONAL },
217 	{ SYS_RES_IRQ,      3,  RF_ACTIVE | RF_OPTIONAL },
218 	{ SYS_RES_IRQ,      4,  RF_ACTIVE | RF_OPTIONAL },
219 	{ SYS_RES_IRQ,      5,  RF_ACTIVE | RF_OPTIONAL },
220 #if defined(SOC_TI_AM335X)
221 	{ SYS_RES_IRQ,      6,  RF_ACTIVE | RF_OPTIONAL },
222 	{ SYS_RES_IRQ,      7,  RF_ACTIVE | RF_OPTIONAL },
223 #endif
224 	{ -1,               0,  0 }
225 };
226 
227 /**
228  *	Structure that stores the driver context.
229  *
230  *	This structure is allocated during driver attach.
231  */
232 struct ti_gpio_softc {
233 	device_t		sc_dev;
234 
235 	/*
236 	 * The memory resource(s) for the PRCM register set, when the device is
237 	 * created the caller can assign up to 6 memory regions depending on
238 	 * the SoC type.
239 	 */
240 	struct resource		*sc_mem_res[MAX_GPIO_BANKS];
241 	struct resource		*sc_irq_res[MAX_GPIO_INTRS];
242 
243 	/* The handle for the register IRQ handlers. */
244 	void			*sc_irq_hdl[MAX_GPIO_INTRS];
245 
246 	/*
247 	 * The following describes the H/W revision of each of the GPIO banks.
248 	 */
249 	uint32_t		sc_revision[MAX_GPIO_BANKS];
250 
251 	struct mtx		sc_mtx;
252 };
253 
254 /**
255  *	Macros for driver mutex locking
256  */
257 #define	TI_GPIO_LOCK(_sc)		mtx_lock(&(_sc)->sc_mtx)
258 #define	TI_GPIO_UNLOCK(_sc)		mtx_unlock(&(_sc)->sc_mtx)
259 #define	TI_GPIO_LOCK_INIT(_sc)		\
260 	mtx_init(&_sc->sc_mtx, device_get_nameunit(_sc->sc_dev), \
261 	    "ti_gpio", MTX_DEF)
262 #define	TI_GPIO_LOCK_DESTROY(_sc)	mtx_destroy(&_sc->sc_mtx)
263 #define	TI_GPIO_ASSERT_LOCKED(_sc)	mtx_assert(&_sc->sc_mtx, MA_OWNED)
264 #define	TI_GPIO_ASSERT_UNLOCKED(_sc)	mtx_assert(&_sc->sc_mtx, MA_NOTOWNED)
265 
266 /**
267  *	ti_gpio_read_4 - reads a 16-bit value from one of the PADCONFS registers
268  *	@sc: GPIO device context
269  *	@bank: The bank to read from
270  *	@off: The offset of a register from the GPIO register address range
271  *
272  *
273  *	RETURNS:
274  *	32-bit value read from the register.
275  */
276 static inline uint32_t
277 ti_gpio_read_4(struct ti_gpio_softc *sc, unsigned int bank, bus_size_t off)
278 {
279 	return (bus_read_4(sc->sc_mem_res[bank], off));
280 }
281 
282 /**
283  *	ti_gpio_write_4 - writes a 32-bit value to one of the PADCONFS registers
284  *	@sc: GPIO device context
285  *	@bank: The bank to write to
286  *	@off: The offset of a register from the GPIO register address range
287  *	@val: The value to write into the register
288  *
289  *	RETURNS:
290  *	nothing
291  */
292 static inline void
293 ti_gpio_write_4(struct ti_gpio_softc *sc, unsigned int bank, bus_size_t off,
294                  uint32_t val)
295 {
296 	bus_write_4(sc->sc_mem_res[bank], off, val);
297 }
298 
299 static inline void
300 ti_gpio_intr_clr(struct ti_gpio_softc *sc, unsigned int bank, uint32_t mask)
301 {
302 
303 	/* We clear both set of registers. */
304 #if defined(SOC_OMAP4) || defined(SOC_TI_AM335X)
305 	ti_gpio_write_4(sc, bank, TI_GPIO_IRQSTATUS_CLR_0, mask);
306 	ti_gpio_write_4(sc, bank, TI_GPIO_IRQSTATUS_CLR_1, mask);
307 #else
308 	ti_gpio_write_4(sc, bank, TI_GPIO_CLEARIRQENABLE1, mask);
309 	ti_gpio_write_4(sc, bank, TI_GPIO_CLEARIRQENABLE2, mask);
310 #endif
311 }
312 
313 /**
314  *	ti_gpio_pin_max - Returns the maximum number of GPIO pins
315  *	@dev: gpio device handle
316  *	@maxpin: pointer to a value that upon return will contain the maximum number
317  *	         of pins in the device.
318  *
319  *
320  *	LOCKING:
321  *	Internally locks the context
322  *
323  *	RETURNS:
324  *	Returns 0 on success otherwise an error code
325  */
326 static int
327 ti_gpio_pin_max(device_t dev, int *maxpin)
328 {
329 	struct ti_gpio_softc *sc = device_get_softc(dev);
330 	unsigned int i;
331 	unsigned int banks = 0;
332 
333 	TI_GPIO_LOCK(sc);
334 
335 	/* Calculate how many valid banks we have and then multiply that by 32 to
336 	 * give use the total number of pins.
337 	 */
338 	for (i = 0; i < ti_max_gpio_banks(); i++) {
339 		if (sc->sc_mem_res[i] != NULL)
340 			banks++;
341 	}
342 
343 	*maxpin = (banks * PINS_PER_BANK) - 1;
344 
345 	TI_GPIO_UNLOCK(sc);
346 
347 	return (0);
348 }
349 
350 /**
351  *	ti_gpio_pin_getcaps - Gets the capabilties of a given pin
352  *	@dev: gpio device handle
353  *	@pin: the number of the pin
354  *	@caps: pointer to a value that upon return will contain the capabilities
355  *
356  *	Currently all pins have the same capability, notably:
357  *	  - GPIO_PIN_INPUT
358  *	  - GPIO_PIN_OUTPUT
359  *	  - GPIO_PIN_PULLUP
360  *	  - GPIO_PIN_PULLDOWN
361  *
362  *	LOCKING:
363  *	Internally locks the context
364  *
365  *	RETURNS:
366  *	Returns 0 on success otherwise an error code
367  */
368 static int
369 ti_gpio_pin_getcaps(device_t dev, uint32_t pin, uint32_t *caps)
370 {
371 	struct ti_gpio_softc *sc = device_get_softc(dev);
372 	uint32_t bank = (pin / PINS_PER_BANK);
373 
374 	TI_GPIO_LOCK(sc);
375 
376 	/* Sanity check the pin number is valid */
377 	if ((bank >= ti_max_gpio_banks()) || (sc->sc_mem_res[bank] == NULL)) {
378 		TI_GPIO_UNLOCK(sc);
379 		return (EINVAL);
380 	}
381 
382 	*caps = (GPIO_PIN_INPUT | GPIO_PIN_OUTPUT |GPIO_PIN_PULLUP |
383 	    GPIO_PIN_PULLDOWN);
384 
385 	TI_GPIO_UNLOCK(sc);
386 
387 	return (0);
388 }
389 
390 /**
391  *	ti_gpio_pin_getflags - Gets the current flags of a given pin
392  *	@dev: gpio device handle
393  *	@pin: the number of the pin
394  *	@flags: upon return will contain the current flags of the pin
395  *
396  *	Reads the current flags of a given pin, here we actually read the H/W
397  *	registers to determine the flags, rather than storing the value in the
398  *	setflags call.
399  *
400  *	LOCKING:
401  *	Internally locks the context
402  *
403  *	RETURNS:
404  *	Returns 0 on success otherwise an error code
405  */
406 static int
407 ti_gpio_pin_getflags(device_t dev, uint32_t pin, uint32_t *flags)
408 {
409 	struct ti_gpio_softc *sc = device_get_softc(dev);
410 	uint32_t bank = (pin / PINS_PER_BANK);
411 
412 	TI_GPIO_LOCK(sc);
413 
414 	/* Sanity check the pin number is valid */
415 	if ((bank >= ti_max_gpio_banks()) || (sc->sc_mem_res[bank] == NULL)) {
416 		TI_GPIO_UNLOCK(sc);
417 		return (EINVAL);
418 	}
419 
420 	/* Get the current pin state */
421 	ti_scm_padconf_get_gpioflags(pin, flags);
422 
423 	TI_GPIO_UNLOCK(sc);
424 
425 	return (0);
426 }
427 
428 /**
429  *	ti_gpio_pin_getname - Gets the name of a given pin
430  *	@dev: gpio device handle
431  *	@pin: the number of the pin
432  *	@name: buffer to put the name in
433  *
434  *	The driver simply calls the pins gpio_n, where 'n' is obviously the number
435  *	of the pin.
436  *
437  *	LOCKING:
438  *	Internally locks the context
439  *
440  *	RETURNS:
441  *	Returns 0 on success otherwise an error code
442  */
443 static int
444 ti_gpio_pin_getname(device_t dev, uint32_t pin, char *name)
445 {
446 	struct ti_gpio_softc *sc = device_get_softc(dev);
447 	uint32_t bank = (pin / PINS_PER_BANK);
448 
449 	TI_GPIO_LOCK(sc);
450 
451 	/* Sanity check the pin number is valid */
452 	if ((bank >= ti_max_gpio_banks()) || (sc->sc_mem_res[bank] == NULL)) {
453 		TI_GPIO_UNLOCK(sc);
454 		return (EINVAL);
455 	}
456 
457 	/* Set a very simple name */
458 	snprintf(name, GPIOMAXNAME, "gpio_%u", pin);
459 	name[GPIOMAXNAME - 1] = '\0';
460 
461 	TI_GPIO_UNLOCK(sc);
462 
463 	return (0);
464 }
465 
466 /**
467  *	ti_gpio_pin_setflags - Sets the flags for a given pin
468  *	@dev: gpio device handle
469  *	@pin: the number of the pin
470  *	@flags: the flags to set
471  *
472  *	The flags of the pin correspond to things like input/output mode, pull-ups,
473  *	pull-downs, etc.  This driver doesn't support all flags, only the following:
474  *	  - GPIO_PIN_INPUT
475  *	  - GPIO_PIN_OUTPUT
476  *	  - GPIO_PIN_PULLUP
477  *	  - GPIO_PIN_PULLDOWN
478  *
479  *	LOCKING:
480  *	Internally locks the context
481  *
482  *	RETURNS:
483  *	Returns 0 on success otherwise an error code
484  */
485 static int
486 ti_gpio_pin_setflags(device_t dev, uint32_t pin, uint32_t flags)
487 {
488 	struct ti_gpio_softc *sc = device_get_softc(dev);
489 	uint32_t bank = (pin / PINS_PER_BANK);
490 	uint32_t mask = (1UL << (pin % PINS_PER_BANK));
491 	uint32_t reg_val;
492 
493 	/* Sanity check the flags supplied are valid, i.e. not input and output */
494 	if ((flags & (GPIO_PIN_INPUT|GPIO_PIN_OUTPUT)) == 0x0000)
495 		return (EINVAL);
496 	if ((flags & (GPIO_PIN_INPUT|GPIO_PIN_OUTPUT)) ==
497 	    (GPIO_PIN_INPUT|GPIO_PIN_OUTPUT))
498 		return (EINVAL);
499 	if ((flags & (GPIO_PIN_PULLUP|GPIO_PIN_PULLDOWN)) ==
500 	    (GPIO_PIN_PULLUP|GPIO_PIN_PULLDOWN))
501 		return (EINVAL);
502 
503 	TI_GPIO_LOCK(sc);
504 
505 	/* Sanity check the pin number is valid */
506 	if ((bank >= ti_max_gpio_banks()) || (sc->sc_mem_res[bank] == NULL)) {
507 		TI_GPIO_UNLOCK(sc);
508 		return (EINVAL);
509 	}
510 
511 	/* Set the GPIO mode and state */
512 	if (ti_scm_padconf_set_gpioflags(pin, flags) != 0) {
513 		TI_GPIO_UNLOCK(sc);
514 		return (EINVAL);
515 	}
516 
517 	/* If configuring as an output set the "output enable" bit */
518 	reg_val = ti_gpio_read_4(sc, bank, TI_GPIO_OE);
519 	if (flags & GPIO_PIN_INPUT)
520 		reg_val |= mask;
521 	else
522 		reg_val &= ~mask;
523 	ti_gpio_write_4(sc, bank, TI_GPIO_OE, reg_val);
524 
525 	TI_GPIO_UNLOCK(sc);
526 
527 	return (0);
528 }
529 
530 /**
531  *	ti_gpio_pin_set - Sets the current level on a GPIO pin
532  *	@dev: gpio device handle
533  *	@pin: the number of the pin
534  *	@value: non-zero value will drive the pin high, otherwise the pin is
535  *	        driven low.
536  *
537  *
538  *	LOCKING:
539  *	Internally locks the context
540  *
541  *	RETURNS:
542  *	Returns 0 on success otherwise a error code
543  */
544 static int
545 ti_gpio_pin_set(device_t dev, uint32_t pin, unsigned int value)
546 {
547 	struct ti_gpio_softc *sc = device_get_softc(dev);
548 	uint32_t bank = (pin / PINS_PER_BANK);
549 	uint32_t mask = (1UL << (pin % PINS_PER_BANK));
550 
551 	TI_GPIO_LOCK(sc);
552 
553 	/* Sanity check the pin number is valid */
554 	if ((bank >= ti_max_gpio_banks()) || (sc->sc_mem_res[bank] == NULL)) {
555 		TI_GPIO_UNLOCK(sc);
556 		return (EINVAL);
557 	}
558 
559 	ti_gpio_write_4(sc, bank, (value == GPIO_PIN_LOW) ? TI_GPIO_CLEARDATAOUT
560 	    : TI_GPIO_SETDATAOUT, mask);
561 
562 	TI_GPIO_UNLOCK(sc);
563 
564 	return (0);
565 }
566 
567 /**
568  *	ti_gpio_pin_get - Gets the current level on a GPIO pin
569  *	@dev: gpio device handle
570  *	@pin: the number of the pin
571  *	@value: pointer to a value that upond return will contain the pin value
572  *
573  *	The pin must be configured as an input pin beforehand, otherwise this
574  *	function will fail.
575  *
576  *	LOCKING:
577  *	Internally locks the context
578  *
579  *	RETURNS:
580  *	Returns 0 on success otherwise a error code
581  */
582 static int
583 ti_gpio_pin_get(device_t dev, uint32_t pin, unsigned int *value)
584 {
585 	struct ti_gpio_softc *sc = device_get_softc(dev);
586 	uint32_t bank = (pin / PINS_PER_BANK);
587 	uint32_t mask = (1UL << (pin % PINS_PER_BANK));
588 	uint32_t val = 0;
589 
590 	TI_GPIO_LOCK(sc);
591 
592 	/* Sanity check the pin number is valid */
593 	if ((bank >= ti_max_gpio_banks()) || (sc->sc_mem_res[bank] == NULL)) {
594 		TI_GPIO_UNLOCK(sc);
595 		return (EINVAL);
596 	}
597 
598 	/* Sanity check the pin is not configured as an output */
599 	val = ti_gpio_read_4(sc, bank, TI_GPIO_OE);
600 
601 	/* Read the value on the pin */
602 	if (val & mask)
603 		*value = (ti_gpio_read_4(sc, bank, TI_GPIO_DATAIN) & mask) ? 1 : 0;
604 	else
605 		*value = (ti_gpio_read_4(sc, bank, TI_GPIO_DATAOUT) & mask) ? 1 : 0;
606 
607 	TI_GPIO_UNLOCK(sc);
608 
609 	return (0);
610 }
611 
612 /**
613  *	ti_gpio_pin_toggle - Toggles a given GPIO pin
614  *	@dev: gpio device handle
615  *	@pin: the number of the pin
616  *
617  *
618  *	LOCKING:
619  *	Internally locks the context
620  *
621  *	RETURNS:
622  *	Returns 0 on success otherwise a error code
623  */
624 static int
625 ti_gpio_pin_toggle(device_t dev, uint32_t pin)
626 {
627 	struct ti_gpio_softc *sc = device_get_softc(dev);
628 	uint32_t bank = (pin / PINS_PER_BANK);
629 	uint32_t mask = (1UL << (pin % PINS_PER_BANK));
630 	uint32_t val;
631 
632 	TI_GPIO_LOCK(sc);
633 
634 	/* Sanity check the pin number is valid */
635 	if ((bank >= ti_max_gpio_banks()) || (sc->sc_mem_res[bank] == NULL)) {
636 		TI_GPIO_UNLOCK(sc);
637 		return (EINVAL);
638 	}
639 
640 	/* Toggle the pin */
641 	val = ti_gpio_read_4(sc, bank, TI_GPIO_DATAOUT);
642 	if (val & mask)
643 		ti_gpio_write_4(sc, bank, TI_GPIO_CLEARDATAOUT, mask);
644 	else
645 		ti_gpio_write_4(sc, bank, TI_GPIO_SETDATAOUT, mask);
646 
647 	TI_GPIO_UNLOCK(sc);
648 
649 	return (0);
650 }
651 
652 /**
653  *	ti_gpio_intr - ISR for all GPIO modules
654  *	@arg: the soft context pointer
655  *
656  *	Unsused
657  *
658  *	LOCKING:
659  *	Internally locks the context
660  *
661  */
662 static void
663 ti_gpio_intr(void *arg)
664 {
665 	struct ti_gpio_softc *sc = arg;
666 
667 	TI_GPIO_LOCK(sc);
668 	/* TODO: something useful */
669 	TI_GPIO_UNLOCK(sc);
670 }
671 
672 /**
673  *	ti_gpio_probe - probe function for the driver
674  *	@dev: gpio device handle
675  *
676  *	Simply sets the name of the driver
677  *
678  *	LOCKING:
679  *	None
680  *
681  *	RETURNS:
682  *	Always returns 0
683  */
684 static int
685 ti_gpio_probe(device_t dev)
686 {
687 
688 	if (!ofw_bus_status_okay(dev))
689 		return (ENXIO);
690 
691 	if (!ofw_bus_is_compatible(dev, "ti,gpio"))
692 		return (ENXIO);
693 
694 	device_set_desc(dev, "TI General Purpose I/O (GPIO)");
695 
696 	return (0);
697 }
698 
699 static int
700 ti_gpio_attach_intr(device_t dev)
701 {
702 	int i;
703 	struct ti_gpio_softc *sc;
704 
705 	sc = device_get_softc(dev);
706 	for (i = 0; i < ti_max_gpio_intrs(); i++) {
707 		if (sc->sc_irq_res[i] == NULL)
708 			break;
709 
710 		/*
711 		 * Register our interrupt handler for each of the IRQ resources.
712 		 */
713 		if (bus_setup_intr(dev, sc->sc_irq_res[i],
714 		    INTR_TYPE_MISC | INTR_MPSAFE, NULL, ti_gpio_intr, sc,
715 		    &sc->sc_irq_hdl[i]) != 0) {
716 			device_printf(dev,
717 			    "WARNING: unable to register interrupt handler\n");
718 			return (-1);
719 		}
720 	}
721 
722 	return (0);
723 }
724 
725 static int
726 ti_gpio_detach_intr(device_t dev)
727 {
728 	int i;
729 	struct ti_gpio_softc *sc;
730 
731 	/* Teardown our interrupt handlers. */
732 	sc = device_get_softc(dev);
733 	for (i = 0; i < ti_max_gpio_intrs(); i++) {
734 		if (sc->sc_irq_res[i] == NULL)
735 			break;
736 
737 		if (sc->sc_irq_hdl[i]) {
738 			bus_teardown_intr(dev, sc->sc_irq_res[i],
739 			    sc->sc_irq_hdl[i]);
740 		}
741 	}
742 
743 	return (0);
744 }
745 
746 static int
747 ti_gpio_bank_init(device_t dev, int bank)
748 {
749 	int pin;
750 	struct ti_gpio_softc *sc;
751 	uint32_t flags, reg_oe;
752 
753 	sc = device_get_softc(dev);
754 
755 	/* Enable the interface and functional clocks for the module. */
756 	ti_prcm_clk_enable(GPIO0_CLK + ti_first_gpio_bank() + bank);
757 
758 	/*
759 	 * Read the revision number of the module.  TI don't publish the
760 	 * actual revision numbers, so instead the values have been
761 	 * determined by experimentation.
762 	 */
763 	sc->sc_revision[bank] = ti_gpio_read_4(sc, bank, TI_GPIO_REVISION);
764 
765 	/* Check the revision. */
766 	if (sc->sc_revision[bank] != ti_gpio_rev()) {
767 		device_printf(dev, "Warning: could not determine the revision "
768 		    "of %u GPIO module (revision:0x%08x)\n",
769 		    bank, sc->sc_revision[bank]);
770 		return (EINVAL);
771 	}
772 
773 	/* Disable interrupts for all pins. */
774 	ti_gpio_intr_clr(sc, bank, 0xffffffff);
775 
776 	/* Init OE register based on pads configuration. */
777 	reg_oe = 0xffffffff;
778 	for (pin = 0; pin < PINS_PER_BANK; pin++) {
779 		ti_scm_padconf_get_gpioflags(PINS_PER_BANK * bank + pin,
780 		    &flags);
781 		if (flags & GPIO_PIN_OUTPUT)
782 			reg_oe &= ~(1UL << pin);
783 	}
784 	ti_gpio_write_4(sc, bank, TI_GPIO_OE, reg_oe);
785 
786 	return (0);
787 }
788 
789 /**
790  *	ti_gpio_attach - attach function for the driver
791  *	@dev: gpio device handle
792  *
793  *	Allocates and sets up the driver context for all GPIO banks.  This function
794  *	expects the memory ranges and IRQs to already be allocated to the driver.
795  *
796  *	LOCKING:
797  *	None
798  *
799  *	RETURNS:
800  *	Always returns 0
801  */
802 static int
803 ti_gpio_attach(device_t dev)
804 {
805 	struct ti_gpio_softc *sc;
806 	unsigned int i;
807 	int err;
808 
809  	sc = device_get_softc(dev);
810 	sc->sc_dev = dev;
811 
812 	TI_GPIO_LOCK_INIT(sc);
813 
814 	/* There are up to 6 different GPIO register sets located in different
815 	 * memory areas on the chip.  The memory range should have been set for
816 	 * the driver when it was added as a child.
817 	 */
818 	if (bus_alloc_resources(dev, ti_gpio_mem_spec, sc->sc_mem_res) != 0) {
819 		device_printf(dev, "Error: could not allocate mem resources\n");
820 		return (ENXIO);
821 	}
822 
823 	/* Request the IRQ resources */
824 	if (bus_alloc_resources(dev, ti_gpio_irq_spec, sc->sc_irq_res) != 0) {
825 		bus_release_resources(dev, ti_gpio_mem_spec, sc->sc_mem_res);
826 		device_printf(dev, "Error: could not allocate irq resources\n");
827 		return (ENXIO);
828 	}
829 
830 	/* Setup the IRQ resources */
831 	if (ti_gpio_attach_intr(dev) != 0) {
832 		ti_gpio_detach_intr(dev);
833 		bus_release_resources(dev, ti_gpio_irq_spec, sc->sc_irq_res);
834 		bus_release_resources(dev, ti_gpio_mem_spec, sc->sc_mem_res);
835 		return (ENXIO);
836 	}
837 
838 	/* We need to go through each block and ensure the clocks are running and
839 	 * the module is enabled.  It might be better to do this only when the
840 	 * pins are configured which would result in less power used if the GPIO
841 	 * pins weren't used ...
842 	 */
843 	for (i = 0; i < ti_max_gpio_banks(); i++) {
844 		if (sc->sc_mem_res[i] != NULL) {
845 			/* Initialize the GPIO module. */
846 			err = ti_gpio_bank_init(dev, i);
847 			if (err != 0) {
848 				ti_gpio_detach_intr(dev);
849 				bus_release_resources(dev, ti_gpio_irq_spec,
850 				    sc->sc_irq_res);
851 				bus_release_resources(dev, ti_gpio_mem_spec,
852 				    sc->sc_mem_res);
853 				return (err);
854 			}
855 		}
856 	}
857 
858 	/* Finish of the probe call */
859 	device_add_child(dev, "gpioc", device_get_unit(dev));
860 	device_add_child(dev, "gpiobus", device_get_unit(dev));
861 
862 	return (bus_generic_attach(dev));
863 }
864 
865 /**
866  *	ti_gpio_detach - detach function for the driver
867  *	@dev: scm device handle
868  *
869  *	Allocates and sets up the driver context, this simply entails creating a
870  *	bus mappings for the SCM register set.
871  *
872  *	LOCKING:
873  *	None
874  *
875  *	RETURNS:
876  *	Always returns 0
877  */
878 static int
879 ti_gpio_detach(device_t dev)
880 {
881 	struct ti_gpio_softc *sc = device_get_softc(dev);
882 	unsigned int i;
883 
884 	KASSERT(mtx_initialized(&sc->sc_mtx), ("gpio mutex not initialized"));
885 
886 	/* Disable all interrupts */
887 	for (i = 0; i < ti_max_gpio_banks(); i++) {
888 		if (sc->sc_mem_res[i] != NULL)
889 			ti_gpio_intr_clr(sc, i, 0xffffffff);
890 	}
891 
892 	bus_generic_detach(dev);
893 
894 	/* Release the memory and IRQ resources. */
895 	ti_gpio_detach_intr(dev);
896 	bus_release_resources(dev, ti_gpio_irq_spec, sc->sc_irq_res);
897 	bus_release_resources(dev, ti_gpio_mem_spec, sc->sc_mem_res);
898 
899 	TI_GPIO_LOCK_DESTROY(sc);
900 
901 	return (0);
902 }
903 
904 static phandle_t
905 ti_gpio_get_node(device_t bus, device_t dev)
906 {
907 
908 	/* We only have one child, the GPIO bus, which needs our own node. */
909 	return (ofw_bus_get_node(bus));
910 }
911 
912 static device_method_t ti_gpio_methods[] = {
913 	DEVMETHOD(device_probe, ti_gpio_probe),
914 	DEVMETHOD(device_attach, ti_gpio_attach),
915 	DEVMETHOD(device_detach, ti_gpio_detach),
916 
917 	/* GPIO protocol */
918 	DEVMETHOD(gpio_pin_max, ti_gpio_pin_max),
919 	DEVMETHOD(gpio_pin_getname, ti_gpio_pin_getname),
920 	DEVMETHOD(gpio_pin_getflags, ti_gpio_pin_getflags),
921 	DEVMETHOD(gpio_pin_getcaps, ti_gpio_pin_getcaps),
922 	DEVMETHOD(gpio_pin_setflags, ti_gpio_pin_setflags),
923 	DEVMETHOD(gpio_pin_get, ti_gpio_pin_get),
924 	DEVMETHOD(gpio_pin_set, ti_gpio_pin_set),
925 	DEVMETHOD(gpio_pin_toggle, ti_gpio_pin_toggle),
926 
927 	/* ofw_bus interface */
928 	DEVMETHOD(ofw_bus_get_node, ti_gpio_get_node),
929 
930 	{0, 0},
931 };
932 
933 static driver_t ti_gpio_driver = {
934 	"gpio",
935 	ti_gpio_methods,
936 	sizeof(struct ti_gpio_softc),
937 };
938 static devclass_t ti_gpio_devclass;
939 
940 DRIVER_MODULE(ti_gpio, simplebus, ti_gpio_driver, ti_gpio_devclass, 0, 0);
941