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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * TI DaVinci GPIO Support
4 *
5 * Copyright (c) 2006-2007 David Brownell
6 * Copyright (c) 2007, MontaVista Software, Inc. <source@mvista.com>
7 */
8
9#include <linux/gpio/driver.h>
10#include <linux/errno.h>
11#include <linux/kernel.h>
12#include <linux/clk.h>
13#include <linux/err.h>
14#include <linux/io.h>
15#include <linux/irq.h>
16#include <linux/irqdomain.h>
17#include <linux/module.h>
18#include <linux/pinctrl/consumer.h>
19#include <linux/platform_device.h>
20#include <linux/property.h>
21#include <linux/irqchip/chained_irq.h>
22#include <linux/spinlock.h>
23#include <linux/pm_runtime.h>
24
25#define MAX_REGS_BANKS 5
26#define MAX_INT_PER_BANK 32
27
28struct davinci_gpio_regs {
29 u32 dir;
30 u32 out_data;
31 u32 set_data;
32 u32 clr_data;
33 u32 in_data;
34 u32 set_rising;
35 u32 clr_rising;
36 u32 set_falling;
37 u32 clr_falling;
38 u32 intstat;
39};
40
41typedef struct irq_chip *(*gpio_get_irq_chip_cb_t)(unsigned int irq);
42
43#define BINTEN 0x8 /* GPIO Interrupt Per-Bank Enable Register */
44
45static void __iomem *gpio_base;
46static unsigned int offset_array[5] = {0x10, 0x38, 0x60, 0x88, 0xb0};
47
48struct davinci_gpio_irq_data {
49 void __iomem *regs;
50 struct davinci_gpio_controller *chip;
51 int bank_num;
52};
53
54struct davinci_gpio_controller {
55 struct gpio_chip chip;
56 struct irq_domain *irq_domain;
57 /* Serialize access to GPIO registers */
58 spinlock_t lock;
59 void __iomem *regs[MAX_REGS_BANKS];
60 int gpio_unbanked;
61 int irqs[MAX_INT_PER_BANK];
62 struct davinci_gpio_regs context[MAX_REGS_BANKS];
63 u32 binten_context;
64};
65
66static inline u32 __gpio_mask(unsigned gpio)
67{
68 return 1 << (gpio % 32);
69}
70
71static inline struct davinci_gpio_regs __iomem *irq2regs(struct irq_data *d)
72{
73 struct davinci_gpio_regs __iomem *g;
74
75 g = (__force struct davinci_gpio_regs __iomem *)irq_data_get_irq_chip_data(d);
76
77 return g;
78}
79
80static int davinci_gpio_irq_setup(struct platform_device *pdev);
81
82/*--------------------------------------------------------------------------*/
83
84/* board setup code *MUST* setup pinmux and enable the GPIO clock. */
85static inline int __davinci_direction(struct gpio_chip *chip,
86 unsigned offset, bool out, int value)
87{
88 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
89 struct davinci_gpio_regs __iomem *g;
90 unsigned long flags;
91 u32 temp;
92 int bank = offset / 32;
93 u32 mask = __gpio_mask(offset);
94
95 g = d->regs[bank];
96 spin_lock_irqsave(&d->lock, flags);
97 temp = readl_relaxed(&g->dir);
98 if (out) {
99 temp &= ~mask;
100 writel_relaxed(mask, value ? &g->set_data : &g->clr_data);
101 } else {
102 temp |= mask;
103 }
104 writel_relaxed(temp, &g->dir);
105 spin_unlock_irqrestore(&d->lock, flags);
106
107 return 0;
108}
109
110static int davinci_direction_in(struct gpio_chip *chip, unsigned offset)
111{
112 return __davinci_direction(chip, offset, false, 0);
113}
114
115static int
116davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value)
117{
118 return __davinci_direction(chip, offset, true, value);
119}
120
121/*
122 * Read the pin's value (works even if it's set up as output);
123 * returns zero/nonzero.
124 *
125 * Note that changes are synched to the GPIO clock, so reading values back
126 * right after you've set them may give old values.
127 */
128static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset)
129{
130 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
131 struct davinci_gpio_regs __iomem *g;
132 int bank = offset / 32;
133
134 g = d->regs[bank];
135
136 return !!(__gpio_mask(offset) & readl_relaxed(&g->in_data));
137}
138
139/*
140 * Assuming the pin is muxed as a gpio output, set its output value.
141 */
142static void
143davinci_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
144{
145 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
146 struct davinci_gpio_regs __iomem *g;
147 int bank = offset / 32;
148
149 g = d->regs[bank];
150
151 writel_relaxed(__gpio_mask(offset),
152 value ? &g->set_data : &g->clr_data);
153}
154
155static int davinci_gpio_probe(struct platform_device *pdev)
156{
157 int bank, i, ret = 0;
158 unsigned int ngpio, nbank, nirq, gpio_unbanked;
159 struct davinci_gpio_controller *chips;
160 struct device *dev = &pdev->dev;
161
162 /*
163 * The gpio banks conceptually expose a segmented bitmap,
164 * and "ngpio" is one more than the largest zero-based
165 * bit index that's valid.
166 */
167 ret = device_property_read_u32(dev, "ti,ngpio", &ngpio);
168 if (ret)
169 return dev_err_probe(dev, ret, "Failed to get the number of GPIOs\n");
170 if (ngpio == 0)
171 return dev_err_probe(dev, -EINVAL, "How many GPIOs?\n");
172
173 /*
174 * If there are unbanked interrupts then the number of
175 * interrupts is equal to number of gpios else all are banked so
176 * number of interrupts is equal to number of banks(each with 16 gpios)
177 */
178 ret = device_property_read_u32(dev, "ti,davinci-gpio-unbanked",
179 &gpio_unbanked);
180 if (ret)
181 return dev_err_probe(dev, ret, "Failed to get the unbanked GPIOs property\n");
182
183 if (gpio_unbanked)
184 nirq = gpio_unbanked;
185 else
186 nirq = DIV_ROUND_UP(ngpio, 16);
187
188 if (nirq > MAX_INT_PER_BANK) {
189 dev_err(dev, "Too many IRQs!\n");
190 return -EINVAL;
191 }
192
193 chips = devm_kzalloc(dev, sizeof(*chips), GFP_KERNEL);
194 if (!chips)
195 return -ENOMEM;
196
197 gpio_base = devm_platform_ioremap_resource(pdev, 0);
198 if (IS_ERR(gpio_base))
199 return PTR_ERR(gpio_base);
200
201 for (i = 0; i < nirq; i++) {
202 chips->irqs[i] = platform_get_irq(pdev, i);
203 if (chips->irqs[i] < 0)
204 return chips->irqs[i];
205 }
206
207 chips->chip.label = dev_name(dev);
208
209 chips->chip.direction_input = davinci_direction_in;
210 chips->chip.get = davinci_gpio_get;
211 chips->chip.direction_output = davinci_direction_out;
212 chips->chip.set = davinci_gpio_set;
213
214 chips->chip.ngpio = ngpio;
215 chips->chip.base = -1;
216
217#ifdef CONFIG_OF_GPIO
218 chips->chip.parent = dev;
219 chips->chip.request = gpiochip_generic_request;
220 chips->chip.free = gpiochip_generic_free;
221#endif
222 spin_lock_init(&chips->lock);
223
224 chips->gpio_unbanked = gpio_unbanked;
225
226 nbank = DIV_ROUND_UP(ngpio, 32);
227 for (bank = 0; bank < nbank; bank++)
228 chips->regs[bank] = gpio_base + offset_array[bank];
229
230 ret = devm_gpiochip_add_data(dev, &chips->chip, chips);
231 if (ret)
232 return ret;
233
234 platform_set_drvdata(pdev, chips);
235 ret = davinci_gpio_irq_setup(pdev);
236 if (ret)
237 return ret;
238
239 return 0;
240}
241
242/*--------------------------------------------------------------------------*/
243/*
244 * We expect irqs will normally be set up as input pins, but they can also be
245 * used as output pins ... which is convenient for testing.
246 *
247 * NOTE: The first few GPIOs also have direct INTC hookups in addition
248 * to their GPIOBNK0 irq, with a bit less overhead.
249 *
250 * All those INTC hookups (direct, plus several IRQ banks) can also
251 * serve as EDMA event triggers.
252 */
253
254static void gpio_irq_mask(struct irq_data *d)
255{
256 struct davinci_gpio_regs __iomem *g = irq2regs(d);
257 uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d);
258
259 writel_relaxed(mask, &g->clr_falling);
260 writel_relaxed(mask, &g->clr_rising);
261}
262
263static void gpio_irq_unmask(struct irq_data *d)
264{
265 struct davinci_gpio_regs __iomem *g = irq2regs(d);
266 uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d);
267 unsigned status = irqd_get_trigger_type(d);
268
269 status &= IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
270 if (!status)
271 status = IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
272
273 if (status & IRQ_TYPE_EDGE_FALLING)
274 writel_relaxed(mask, &g->set_falling);
275 if (status & IRQ_TYPE_EDGE_RISING)
276 writel_relaxed(mask, &g->set_rising);
277}
278
279static int gpio_irq_type(struct irq_data *d, unsigned trigger)
280{
281 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
282 return -EINVAL;
283
284 return 0;
285}
286
287static struct irq_chip gpio_irqchip = {
288 .name = "GPIO",
289 .irq_unmask = gpio_irq_unmask,
290 .irq_mask = gpio_irq_mask,
291 .irq_set_type = gpio_irq_type,
292 .flags = IRQCHIP_SET_TYPE_MASKED | IRQCHIP_SKIP_SET_WAKE,
293};
294
295static void gpio_irq_handler(struct irq_desc *desc)
296{
297 struct davinci_gpio_regs __iomem *g;
298 u32 mask = 0xffff;
299 int bank_num;
300 struct davinci_gpio_controller *d;
301 struct davinci_gpio_irq_data *irqdata;
302
303 irqdata = (struct davinci_gpio_irq_data *)irq_desc_get_handler_data(desc);
304 bank_num = irqdata->bank_num;
305 g = irqdata->regs;
306 d = irqdata->chip;
307
308 /* we only care about one bank */
309 if ((bank_num % 2) == 1)
310 mask <<= 16;
311
312 /* temporarily mask (level sensitive) parent IRQ */
313 chained_irq_enter(irq_desc_get_chip(desc), desc);
314 while (1) {
315 u32 status;
316 int bit;
317 irq_hw_number_t hw_irq;
318
319 /* ack any irqs */
320 status = readl_relaxed(&g->intstat) & mask;
321 if (!status)
322 break;
323 writel_relaxed(status, &g->intstat);
324
325 /* now demux them to the right lowlevel handler */
326
327 while (status) {
328 bit = __ffs(status);
329 status &= ~BIT(bit);
330 /* Max number of gpios per controller is 144 so
331 * hw_irq will be in [0..143]
332 */
333 hw_irq = (bank_num / 2) * 32 + bit;
334
335 generic_handle_domain_irq(d->irq_domain, hw_irq);
336 }
337 }
338 chained_irq_exit(irq_desc_get_chip(desc), desc);
339 /* now it may re-trigger */
340}
341
342static int gpio_to_irq_banked(struct gpio_chip *chip, unsigned offset)
343{
344 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
345
346 if (d->irq_domain)
347 return irq_create_mapping(d->irq_domain, offset);
348 else
349 return -ENXIO;
350}
351
352static int gpio_to_irq_unbanked(struct gpio_chip *chip, unsigned offset)
353{
354 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
355
356 /*
357 * NOTE: we assume for now that only irqs in the first gpio_chip
358 * can provide direct-mapped IRQs to AINTC (up to 32 GPIOs).
359 */
360 if (offset < d->gpio_unbanked)
361 return d->irqs[offset];
362 else
363 return -ENODEV;
364}
365
366static int gpio_irq_type_unbanked(struct irq_data *data, unsigned trigger)
367{
368 struct davinci_gpio_controller *d;
369 struct davinci_gpio_regs __iomem *g;
370 u32 mask, i;
371
372 d = (struct davinci_gpio_controller *)irq_data_get_irq_handler_data(data);
373 g = (struct davinci_gpio_regs __iomem *)d->regs[0];
374 for (i = 0; i < MAX_INT_PER_BANK; i++)
375 if (data->irq == d->irqs[i])
376 break;
377
378 if (i == MAX_INT_PER_BANK)
379 return -EINVAL;
380
381 mask = __gpio_mask(i);
382
383 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
384 return -EINVAL;
385
386 writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_FALLING)
387 ? &g->set_falling : &g->clr_falling);
388 writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_RISING)
389 ? &g->set_rising : &g->clr_rising);
390
391 return 0;
392}
393
394static int
395davinci_gpio_irq_map(struct irq_domain *d, unsigned int irq,
396 irq_hw_number_t hw)
397{
398 struct davinci_gpio_controller *chips =
399 (struct davinci_gpio_controller *)d->host_data;
400 struct davinci_gpio_regs __iomem *g = chips->regs[hw / 32];
401
402 irq_set_chip_and_handler_name(irq, &gpio_irqchip, handle_simple_irq,
403 "davinci_gpio");
404 irq_set_irq_type(irq, IRQ_TYPE_NONE);
405 irq_set_chip_data(irq, (__force void *)g);
406 irq_set_handler_data(irq, (void *)(uintptr_t)__gpio_mask(hw));
407
408 return 0;
409}
410
411static const struct irq_domain_ops davinci_gpio_irq_ops = {
412 .map = davinci_gpio_irq_map,
413 .xlate = irq_domain_xlate_onetwocell,
414};
415
416static struct irq_chip *davinci_gpio_get_irq_chip(unsigned int irq)
417{
418 static struct irq_chip_type gpio_unbanked;
419
420 gpio_unbanked = *irq_data_get_chip_type(irq_get_irq_data(irq));
421
422 return &gpio_unbanked.chip;
423};
424
425static struct irq_chip *keystone_gpio_get_irq_chip(unsigned int irq)
426{
427 static struct irq_chip gpio_unbanked;
428
429 gpio_unbanked = *irq_get_chip(irq);
430 return &gpio_unbanked;
431};
432
433static const struct of_device_id davinci_gpio_ids[];
434
435/*
436 * NOTE: for suspend/resume, probably best to make a platform_device with
437 * suspend_late/resume_resume calls hooking into results of the set_wake()
438 * calls ... so if no gpios are wakeup events the clock can be disabled,
439 * with outputs left at previously set levels, and so that VDD3P3V.IOPWDN0
440 * (dm6446) can be set appropriately for GPIOV33 pins.
441 */
442
443static int davinci_gpio_irq_setup(struct platform_device *pdev)
444{
445 unsigned gpio, bank;
446 int irq;
447 struct clk *clk;
448 u32 binten = 0;
449 unsigned ngpio;
450 struct device *dev = &pdev->dev;
451 struct davinci_gpio_controller *chips = platform_get_drvdata(pdev);
452 struct davinci_gpio_regs __iomem *g;
453 struct irq_domain *irq_domain = NULL;
454 struct irq_chip *irq_chip;
455 struct davinci_gpio_irq_data *irqdata;
456 gpio_get_irq_chip_cb_t gpio_get_irq_chip;
457
458 /*
459 * Use davinci_gpio_get_irq_chip by default to handle non DT cases
460 */
461 gpio_get_irq_chip = davinci_gpio_get_irq_chip;
462 if (dev->of_node)
463 gpio_get_irq_chip = (gpio_get_irq_chip_cb_t)device_get_match_data(dev);
464
465 ngpio = chips->chip.ngpio;
466
467 clk = devm_clk_get_enabled(dev, "gpio");
468 if (IS_ERR(clk)) {
469 dev_err(dev, "Error %ld getting gpio clock\n", PTR_ERR(clk));
470 return PTR_ERR(clk);
471 }
472
473 if (!chips->gpio_unbanked) {
474 irq = devm_irq_alloc_descs(dev, -1, 0, ngpio, 0);
475 if (irq < 0) {
476 dev_err(dev, "Couldn't allocate IRQ numbers\n");
477 return irq;
478 }
479
480 irq_domain = irq_domain_add_legacy(dev->of_node, ngpio, irq, 0,
481 &davinci_gpio_irq_ops,
482 chips);
483 if (!irq_domain) {
484 dev_err(dev, "Couldn't register an IRQ domain\n");
485 return -ENODEV;
486 }
487 }
488
489 /*
490 * Arrange gpiod_to_irq() support, handling either direct IRQs or
491 * banked IRQs. Having GPIOs in the first GPIO bank use direct
492 * IRQs, while the others use banked IRQs, would need some setup
493 * tweaks to recognize hardware which can do that.
494 */
495 chips->chip.to_irq = gpio_to_irq_banked;
496 chips->irq_domain = irq_domain;
497
498 /*
499 * AINTC can handle direct/unbanked IRQs for GPIOs, with the GPIO
500 * controller only handling trigger modes. We currently assume no
501 * IRQ mux conflicts; gpio_irq_type_unbanked() is only for GPIOs.
502 */
503 if (chips->gpio_unbanked) {
504 /* pass "bank 0" GPIO IRQs to AINTC */
505 chips->chip.to_irq = gpio_to_irq_unbanked;
506
507 binten = GENMASK(chips->gpio_unbanked / 16, 0);
508
509 /* AINTC handles mask/unmask; GPIO handles triggering */
510 irq = chips->irqs[0];
511 irq_chip = gpio_get_irq_chip(irq);
512 irq_chip->name = "GPIO-AINTC";
513 irq_chip->irq_set_type = gpio_irq_type_unbanked;
514
515 /* default trigger: both edges */
516 g = chips->regs[0];
517 writel_relaxed(~0, &g->set_falling);
518 writel_relaxed(~0, &g->set_rising);
519
520 /* set the direct IRQs up to use that irqchip */
521 for (gpio = 0; gpio < chips->gpio_unbanked; gpio++) {
522 irq_set_chip(chips->irqs[gpio], irq_chip);
523 irq_set_handler_data(chips->irqs[gpio], chips);
524 irq_set_status_flags(chips->irqs[gpio],
525 IRQ_TYPE_EDGE_BOTH);
526 }
527
528 goto done;
529 }
530
531 /*
532 * Or, AINTC can handle IRQs for banks of 16 GPIO IRQs, which we
533 * then chain through our own handler.
534 */
535 for (gpio = 0, bank = 0; gpio < ngpio; bank++, gpio += 16) {
536 /* disabled by default, enabled only as needed
537 * There are register sets for 32 GPIOs. 2 banks of 16
538 * GPIOs are covered by each set of registers hence divide by 2
539 */
540 g = chips->regs[bank / 2];
541 writel_relaxed(~0, &g->clr_falling);
542 writel_relaxed(~0, &g->clr_rising);
543
544 /*
545 * Each chip handles 32 gpios, and each irq bank consists of 16
546 * gpio irqs. Pass the irq bank's corresponding controller to
547 * the chained irq handler.
548 */
549 irqdata = devm_kzalloc(&pdev->dev,
550 sizeof(struct
551 davinci_gpio_irq_data),
552 GFP_KERNEL);
553 if (!irqdata)
554 return -ENOMEM;
555
556 irqdata->regs = g;
557 irqdata->bank_num = bank;
558 irqdata->chip = chips;
559
560 irq_set_chained_handler_and_data(chips->irqs[bank],
561 gpio_irq_handler, irqdata);
562
563 binten |= BIT(bank);
564 }
565
566done:
567 /*
568 * BINTEN -- per-bank interrupt enable. genirq would also let these
569 * bits be set/cleared dynamically.
570 */
571 writel_relaxed(binten, gpio_base + BINTEN);
572
573 return 0;
574}
575
576static void davinci_gpio_save_context(struct davinci_gpio_controller *chips,
577 u32 nbank)
578{
579 struct davinci_gpio_regs __iomem *g;
580 struct davinci_gpio_regs *context;
581 u32 bank;
582 void __iomem *base;
583
584 base = chips->regs[0] - offset_array[0];
585 chips->binten_context = readl_relaxed(base + BINTEN);
586
587 for (bank = 0; bank < nbank; bank++) {
588 g = chips->regs[bank];
589 context = &chips->context[bank];
590 context->dir = readl_relaxed(&g->dir);
591 context->set_data = readl_relaxed(&g->set_data);
592 context->set_rising = readl_relaxed(&g->set_rising);
593 context->set_falling = readl_relaxed(&g->set_falling);
594 }
595
596 /* Clear all interrupt status registers */
597 writel_relaxed(GENMASK(31, 0), &g->intstat);
598}
599
600static void davinci_gpio_restore_context(struct davinci_gpio_controller *chips,
601 u32 nbank)
602{
603 struct davinci_gpio_regs __iomem *g;
604 struct davinci_gpio_regs *context;
605 u32 bank;
606 void __iomem *base;
607
608 base = chips->regs[0] - offset_array[0];
609
610 if (readl_relaxed(base + BINTEN) != chips->binten_context)
611 writel_relaxed(chips->binten_context, base + BINTEN);
612
613 for (bank = 0; bank < nbank; bank++) {
614 g = chips->regs[bank];
615 context = &chips->context[bank];
616 if (readl_relaxed(&g->dir) != context->dir)
617 writel_relaxed(context->dir, &g->dir);
618 if (readl_relaxed(&g->set_data) != context->set_data)
619 writel_relaxed(context->set_data, &g->set_data);
620 if (readl_relaxed(&g->set_rising) != context->set_rising)
621 writel_relaxed(context->set_rising, &g->set_rising);
622 if (readl_relaxed(&g->set_falling) != context->set_falling)
623 writel_relaxed(context->set_falling, &g->set_falling);
624 }
625}
626
627static int davinci_gpio_suspend(struct device *dev)
628{
629 struct davinci_gpio_controller *chips = dev_get_drvdata(dev);
630 u32 nbank = DIV_ROUND_UP(chips->chip.ngpio, 32);
631
632 davinci_gpio_save_context(chips, nbank);
633
634 return 0;
635}
636
637static int davinci_gpio_resume(struct device *dev)
638{
639 struct davinci_gpio_controller *chips = dev_get_drvdata(dev);
640 u32 nbank = DIV_ROUND_UP(chips->chip.ngpio, 32);
641
642 davinci_gpio_restore_context(chips, nbank);
643
644 return 0;
645}
646
647static DEFINE_SIMPLE_DEV_PM_OPS(davinci_gpio_dev_pm_ops, davinci_gpio_suspend,
648 davinci_gpio_resume);
649
650static const struct of_device_id davinci_gpio_ids[] = {
651 { .compatible = "ti,keystone-gpio", keystone_gpio_get_irq_chip},
652 { .compatible = "ti,am654-gpio", keystone_gpio_get_irq_chip},
653 { .compatible = "ti,dm6441-gpio", davinci_gpio_get_irq_chip},
654 { /* sentinel */ },
655};
656MODULE_DEVICE_TABLE(of, davinci_gpio_ids);
657
658static struct platform_driver davinci_gpio_driver = {
659 .probe = davinci_gpio_probe,
660 .driver = {
661 .name = "davinci_gpio",
662 .pm = pm_sleep_ptr(&davinci_gpio_dev_pm_ops),
663 .of_match_table = davinci_gpio_ids,
664 },
665};
666
667/*
668 * GPIO driver registration needs to be done before machine_init functions
669 * access GPIO. Hence davinci_gpio_drv_reg() is a postcore_initcall.
670 */
671static int __init davinci_gpio_drv_reg(void)
672{
673 return platform_driver_register(&davinci_gpio_driver);
674}
675postcore_initcall(davinci_gpio_drv_reg);
676
677static void __exit davinci_gpio_exit(void)
678{
679 platform_driver_unregister(&davinci_gpio_driver);
680}
681module_exit(davinci_gpio_exit);
682
683MODULE_AUTHOR("Jan Kotas <jank@cadence.com>");
684MODULE_DESCRIPTION("DAVINCI GPIO driver");
685MODULE_LICENSE("GPL");
686MODULE_ALIAS("platform:gpio-davinci");
1/*
2 * TI DaVinci GPIO Support
3 *
4 * Copyright (c) 2006-2007 David Brownell
5 * Copyright (c) 2007, MontaVista Software, Inc. <source@mvista.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 */
12#include <linux/gpio.h>
13#include <linux/errno.h>
14#include <linux/kernel.h>
15#include <linux/clk.h>
16#include <linux/err.h>
17#include <linux/io.h>
18#include <linux/irq.h>
19#include <linux/irqdomain.h>
20#include <linux/module.h>
21#include <linux/of.h>
22#include <linux/of_device.h>
23#include <linux/platform_device.h>
24#include <linux/platform_data/gpio-davinci.h>
25#include <linux/irqchip/chained_irq.h>
26
27struct davinci_gpio_regs {
28 u32 dir;
29 u32 out_data;
30 u32 set_data;
31 u32 clr_data;
32 u32 in_data;
33 u32 set_rising;
34 u32 clr_rising;
35 u32 set_falling;
36 u32 clr_falling;
37 u32 intstat;
38};
39
40typedef struct irq_chip *(*gpio_get_irq_chip_cb_t)(unsigned int irq);
41
42#define BINTEN 0x8 /* GPIO Interrupt Per-Bank Enable Register */
43#define MAX_LABEL_SIZE 20
44
45static void __iomem *gpio_base;
46
47static struct davinci_gpio_regs __iomem *gpio2regs(unsigned gpio)
48{
49 void __iomem *ptr;
50
51 if (gpio < 32 * 1)
52 ptr = gpio_base + 0x10;
53 else if (gpio < 32 * 2)
54 ptr = gpio_base + 0x38;
55 else if (gpio < 32 * 3)
56 ptr = gpio_base + 0x60;
57 else if (gpio < 32 * 4)
58 ptr = gpio_base + 0x88;
59 else if (gpio < 32 * 5)
60 ptr = gpio_base + 0xb0;
61 else
62 ptr = NULL;
63 return ptr;
64}
65
66static inline struct davinci_gpio_regs __iomem *irq2regs(struct irq_data *d)
67{
68 struct davinci_gpio_regs __iomem *g;
69
70 g = (__force struct davinci_gpio_regs __iomem *)irq_data_get_irq_chip_data(d);
71
72 return g;
73}
74
75static int davinci_gpio_irq_setup(struct platform_device *pdev);
76
77/*--------------------------------------------------------------------------*/
78
79/* board setup code *MUST* setup pinmux and enable the GPIO clock. */
80static inline int __davinci_direction(struct gpio_chip *chip,
81 unsigned offset, bool out, int value)
82{
83 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
84 struct davinci_gpio_regs __iomem *g = d->regs;
85 unsigned long flags;
86 u32 temp;
87 u32 mask = 1 << offset;
88
89 spin_lock_irqsave(&d->lock, flags);
90 temp = readl_relaxed(&g->dir);
91 if (out) {
92 temp &= ~mask;
93 writel_relaxed(mask, value ? &g->set_data : &g->clr_data);
94 } else {
95 temp |= mask;
96 }
97 writel_relaxed(temp, &g->dir);
98 spin_unlock_irqrestore(&d->lock, flags);
99
100 return 0;
101}
102
103static int davinci_direction_in(struct gpio_chip *chip, unsigned offset)
104{
105 return __davinci_direction(chip, offset, false, 0);
106}
107
108static int
109davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value)
110{
111 return __davinci_direction(chip, offset, true, value);
112}
113
114/*
115 * Read the pin's value (works even if it's set up as output);
116 * returns zero/nonzero.
117 *
118 * Note that changes are synched to the GPIO clock, so reading values back
119 * right after you've set them may give old values.
120 */
121static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset)
122{
123 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
124 struct davinci_gpio_regs __iomem *g = d->regs;
125
126 return !!((1 << offset) & readl_relaxed(&g->in_data));
127}
128
129/*
130 * Assuming the pin is muxed as a gpio output, set its output value.
131 */
132static void
133davinci_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
134{
135 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
136 struct davinci_gpio_regs __iomem *g = d->regs;
137
138 writel_relaxed((1 << offset), value ? &g->set_data : &g->clr_data);
139}
140
141static struct davinci_gpio_platform_data *
142davinci_gpio_get_pdata(struct platform_device *pdev)
143{
144 struct device_node *dn = pdev->dev.of_node;
145 struct davinci_gpio_platform_data *pdata;
146 int ret;
147 u32 val;
148
149 if (!IS_ENABLED(CONFIG_OF) || !pdev->dev.of_node)
150 return dev_get_platdata(&pdev->dev);
151
152 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
153 if (!pdata)
154 return NULL;
155
156 ret = of_property_read_u32(dn, "ti,ngpio", &val);
157 if (ret)
158 goto of_err;
159
160 pdata->ngpio = val;
161
162 ret = of_property_read_u32(dn, "ti,davinci-gpio-unbanked", &val);
163 if (ret)
164 goto of_err;
165
166 pdata->gpio_unbanked = val;
167
168 return pdata;
169
170of_err:
171 dev_err(&pdev->dev, "Populating pdata from DT failed: err %d\n", ret);
172 return NULL;
173}
174
175#ifdef CONFIG_OF_GPIO
176static int davinci_gpio_of_xlate(struct gpio_chip *gc,
177 const struct of_phandle_args *gpiospec,
178 u32 *flags)
179{
180 struct davinci_gpio_controller *chips = dev_get_drvdata(gc->parent);
181 struct davinci_gpio_platform_data *pdata = dev_get_platdata(gc->parent);
182
183 if (gpiospec->args[0] > pdata->ngpio)
184 return -EINVAL;
185
186 if (gc != &chips[gpiospec->args[0] / 32].chip)
187 return -EINVAL;
188
189 if (flags)
190 *flags = gpiospec->args[1];
191
192 return gpiospec->args[0] % 32;
193}
194#endif
195
196static int davinci_gpio_probe(struct platform_device *pdev)
197{
198 int i, base;
199 unsigned ngpio, nbank;
200 struct davinci_gpio_controller *chips;
201 struct davinci_gpio_platform_data *pdata;
202 struct davinci_gpio_regs __iomem *regs;
203 struct device *dev = &pdev->dev;
204 struct resource *res;
205 char label[MAX_LABEL_SIZE];
206
207 pdata = davinci_gpio_get_pdata(pdev);
208 if (!pdata) {
209 dev_err(dev, "No platform data found\n");
210 return -EINVAL;
211 }
212
213 dev->platform_data = pdata;
214
215 /*
216 * The gpio banks conceptually expose a segmented bitmap,
217 * and "ngpio" is one more than the largest zero-based
218 * bit index that's valid.
219 */
220 ngpio = pdata->ngpio;
221 if (ngpio == 0) {
222 dev_err(dev, "How many GPIOs?\n");
223 return -EINVAL;
224 }
225
226 if (WARN_ON(ARCH_NR_GPIOS < ngpio))
227 ngpio = ARCH_NR_GPIOS;
228
229 nbank = DIV_ROUND_UP(ngpio, 32);
230 chips = devm_kzalloc(dev,
231 nbank * sizeof(struct davinci_gpio_controller),
232 GFP_KERNEL);
233 if (!chips)
234 return -ENOMEM;
235
236 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
237 gpio_base = devm_ioremap_resource(dev, res);
238 if (IS_ERR(gpio_base))
239 return PTR_ERR(gpio_base);
240
241 for (i = 0, base = 0; base < ngpio; i++, base += 32) {
242 snprintf(label, MAX_LABEL_SIZE, "davinci_gpio.%d", i);
243 chips[i].chip.label = devm_kstrdup(dev, label, GFP_KERNEL);
244 if (!chips[i].chip.label)
245 return -ENOMEM;
246
247 chips[i].chip.direction_input = davinci_direction_in;
248 chips[i].chip.get = davinci_gpio_get;
249 chips[i].chip.direction_output = davinci_direction_out;
250 chips[i].chip.set = davinci_gpio_set;
251
252 chips[i].chip.base = base;
253 chips[i].chip.ngpio = ngpio - base;
254 if (chips[i].chip.ngpio > 32)
255 chips[i].chip.ngpio = 32;
256
257#ifdef CONFIG_OF_GPIO
258 chips[i].chip.of_gpio_n_cells = 2;
259 chips[i].chip.of_xlate = davinci_gpio_of_xlate;
260 chips[i].chip.parent = dev;
261 chips[i].chip.of_node = dev->of_node;
262#endif
263 spin_lock_init(&chips[i].lock);
264
265 regs = gpio2regs(base);
266 if (!regs)
267 return -ENXIO;
268 chips[i].regs = regs;
269 chips[i].set_data = ®s->set_data;
270 chips[i].clr_data = ®s->clr_data;
271 chips[i].in_data = ®s->in_data;
272
273 gpiochip_add_data(&chips[i].chip, &chips[i]);
274 }
275
276 platform_set_drvdata(pdev, chips);
277 davinci_gpio_irq_setup(pdev);
278 return 0;
279}
280
281/*--------------------------------------------------------------------------*/
282/*
283 * We expect irqs will normally be set up as input pins, but they can also be
284 * used as output pins ... which is convenient for testing.
285 *
286 * NOTE: The first few GPIOs also have direct INTC hookups in addition
287 * to their GPIOBNK0 irq, with a bit less overhead.
288 *
289 * All those INTC hookups (direct, plus several IRQ banks) can also
290 * serve as EDMA event triggers.
291 */
292
293static void gpio_irq_disable(struct irq_data *d)
294{
295 struct davinci_gpio_regs __iomem *g = irq2regs(d);
296 u32 mask = (u32) irq_data_get_irq_handler_data(d);
297
298 writel_relaxed(mask, &g->clr_falling);
299 writel_relaxed(mask, &g->clr_rising);
300}
301
302static void gpio_irq_enable(struct irq_data *d)
303{
304 struct davinci_gpio_regs __iomem *g = irq2regs(d);
305 u32 mask = (u32) irq_data_get_irq_handler_data(d);
306 unsigned status = irqd_get_trigger_type(d);
307
308 status &= IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
309 if (!status)
310 status = IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
311
312 if (status & IRQ_TYPE_EDGE_FALLING)
313 writel_relaxed(mask, &g->set_falling);
314 if (status & IRQ_TYPE_EDGE_RISING)
315 writel_relaxed(mask, &g->set_rising);
316}
317
318static int gpio_irq_type(struct irq_data *d, unsigned trigger)
319{
320 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
321 return -EINVAL;
322
323 return 0;
324}
325
326static struct irq_chip gpio_irqchip = {
327 .name = "GPIO",
328 .irq_enable = gpio_irq_enable,
329 .irq_disable = gpio_irq_disable,
330 .irq_set_type = gpio_irq_type,
331 .flags = IRQCHIP_SET_TYPE_MASKED,
332};
333
334static void gpio_irq_handler(struct irq_desc *desc)
335{
336 unsigned int irq = irq_desc_get_irq(desc);
337 struct davinci_gpio_regs __iomem *g;
338 u32 mask = 0xffff;
339 struct davinci_gpio_controller *d;
340
341 d = (struct davinci_gpio_controller *)irq_desc_get_handler_data(desc);
342 g = (struct davinci_gpio_regs __iomem *)d->regs;
343
344 /* we only care about one bank */
345 if (irq & 1)
346 mask <<= 16;
347
348 /* temporarily mask (level sensitive) parent IRQ */
349 chained_irq_enter(irq_desc_get_chip(desc), desc);
350 while (1) {
351 u32 status;
352 int bit;
353
354 /* ack any irqs */
355 status = readl_relaxed(&g->intstat) & mask;
356 if (!status)
357 break;
358 writel_relaxed(status, &g->intstat);
359
360 /* now demux them to the right lowlevel handler */
361
362 while (status) {
363 bit = __ffs(status);
364 status &= ~BIT(bit);
365 generic_handle_irq(
366 irq_find_mapping(d->irq_domain,
367 d->chip.base + bit));
368 }
369 }
370 chained_irq_exit(irq_desc_get_chip(desc), desc);
371 /* now it may re-trigger */
372}
373
374static int gpio_to_irq_banked(struct gpio_chip *chip, unsigned offset)
375{
376 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
377
378 if (d->irq_domain)
379 return irq_create_mapping(d->irq_domain, d->chip.base + offset);
380 else
381 return -ENXIO;
382}
383
384static int gpio_to_irq_unbanked(struct gpio_chip *chip, unsigned offset)
385{
386 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
387
388 /*
389 * NOTE: we assume for now that only irqs in the first gpio_chip
390 * can provide direct-mapped IRQs to AINTC (up to 32 GPIOs).
391 */
392 if (offset < d->gpio_unbanked)
393 return d->gpio_irq + offset;
394 else
395 return -ENODEV;
396}
397
398static int gpio_irq_type_unbanked(struct irq_data *data, unsigned trigger)
399{
400 struct davinci_gpio_controller *d;
401 struct davinci_gpio_regs __iomem *g;
402 u32 mask;
403
404 d = (struct davinci_gpio_controller *)irq_data_get_irq_handler_data(data);
405 g = (struct davinci_gpio_regs __iomem *)d->regs;
406 mask = __gpio_mask(data->irq - d->gpio_irq);
407
408 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
409 return -EINVAL;
410
411 writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_FALLING)
412 ? &g->set_falling : &g->clr_falling);
413 writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_RISING)
414 ? &g->set_rising : &g->clr_rising);
415
416 return 0;
417}
418
419static int
420davinci_gpio_irq_map(struct irq_domain *d, unsigned int irq,
421 irq_hw_number_t hw)
422{
423 struct davinci_gpio_regs __iomem *g = gpio2regs(hw);
424
425 irq_set_chip_and_handler_name(irq, &gpio_irqchip, handle_simple_irq,
426 "davinci_gpio");
427 irq_set_irq_type(irq, IRQ_TYPE_NONE);
428 irq_set_chip_data(irq, (__force void *)g);
429 irq_set_handler_data(irq, (void *)__gpio_mask(hw));
430
431 return 0;
432}
433
434static const struct irq_domain_ops davinci_gpio_irq_ops = {
435 .map = davinci_gpio_irq_map,
436 .xlate = irq_domain_xlate_onetwocell,
437};
438
439static struct irq_chip *davinci_gpio_get_irq_chip(unsigned int irq)
440{
441 static struct irq_chip_type gpio_unbanked;
442
443 gpio_unbanked = *irq_data_get_chip_type(irq_get_irq_data(irq));
444
445 return &gpio_unbanked.chip;
446};
447
448static struct irq_chip *keystone_gpio_get_irq_chip(unsigned int irq)
449{
450 static struct irq_chip gpio_unbanked;
451
452 gpio_unbanked = *irq_get_chip(irq);
453 return &gpio_unbanked;
454};
455
456static const struct of_device_id davinci_gpio_ids[];
457
458/*
459 * NOTE: for suspend/resume, probably best to make a platform_device with
460 * suspend_late/resume_resume calls hooking into results of the set_wake()
461 * calls ... so if no gpios are wakeup events the clock can be disabled,
462 * with outputs left at previously set levels, and so that VDD3P3V.IOPWDN0
463 * (dm6446) can be set appropriately for GPIOV33 pins.
464 */
465
466static int davinci_gpio_irq_setup(struct platform_device *pdev)
467{
468 unsigned gpio, bank;
469 int irq;
470 struct clk *clk;
471 u32 binten = 0;
472 unsigned ngpio, bank_irq;
473 struct device *dev = &pdev->dev;
474 struct resource *res;
475 struct davinci_gpio_controller *chips = platform_get_drvdata(pdev);
476 struct davinci_gpio_platform_data *pdata = dev->platform_data;
477 struct davinci_gpio_regs __iomem *g;
478 struct irq_domain *irq_domain = NULL;
479 const struct of_device_id *match;
480 struct irq_chip *irq_chip;
481 gpio_get_irq_chip_cb_t gpio_get_irq_chip;
482
483 /*
484 * Use davinci_gpio_get_irq_chip by default to handle non DT cases
485 */
486 gpio_get_irq_chip = davinci_gpio_get_irq_chip;
487 match = of_match_device(of_match_ptr(davinci_gpio_ids),
488 dev);
489 if (match)
490 gpio_get_irq_chip = (gpio_get_irq_chip_cb_t)match->data;
491
492 ngpio = pdata->ngpio;
493 res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
494 if (!res) {
495 dev_err(dev, "Invalid IRQ resource\n");
496 return -EBUSY;
497 }
498
499 bank_irq = res->start;
500
501 if (!bank_irq) {
502 dev_err(dev, "Invalid IRQ resource\n");
503 return -ENODEV;
504 }
505
506 clk = devm_clk_get(dev, "gpio");
507 if (IS_ERR(clk)) {
508 printk(KERN_ERR "Error %ld getting gpio clock?\n",
509 PTR_ERR(clk));
510 return PTR_ERR(clk);
511 }
512 clk_prepare_enable(clk);
513
514 if (!pdata->gpio_unbanked) {
515 irq = irq_alloc_descs(-1, 0, ngpio, 0);
516 if (irq < 0) {
517 dev_err(dev, "Couldn't allocate IRQ numbers\n");
518 return irq;
519 }
520
521 irq_domain = irq_domain_add_legacy(dev->of_node, ngpio, irq, 0,
522 &davinci_gpio_irq_ops,
523 chips);
524 if (!irq_domain) {
525 dev_err(dev, "Couldn't register an IRQ domain\n");
526 return -ENODEV;
527 }
528 }
529
530 /*
531 * Arrange gpio_to_irq() support, handling either direct IRQs or
532 * banked IRQs. Having GPIOs in the first GPIO bank use direct
533 * IRQs, while the others use banked IRQs, would need some setup
534 * tweaks to recognize hardware which can do that.
535 */
536 for (gpio = 0, bank = 0; gpio < ngpio; bank++, gpio += 32) {
537 chips[bank].chip.to_irq = gpio_to_irq_banked;
538 chips[bank].irq_domain = irq_domain;
539 }
540
541 /*
542 * AINTC can handle direct/unbanked IRQs for GPIOs, with the GPIO
543 * controller only handling trigger modes. We currently assume no
544 * IRQ mux conflicts; gpio_irq_type_unbanked() is only for GPIOs.
545 */
546 if (pdata->gpio_unbanked) {
547 /* pass "bank 0" GPIO IRQs to AINTC */
548 chips[0].chip.to_irq = gpio_to_irq_unbanked;
549 chips[0].gpio_irq = bank_irq;
550 chips[0].gpio_unbanked = pdata->gpio_unbanked;
551 binten = GENMASK(pdata->gpio_unbanked / 16, 0);
552
553 /* AINTC handles mask/unmask; GPIO handles triggering */
554 irq = bank_irq;
555 irq_chip = gpio_get_irq_chip(irq);
556 irq_chip->name = "GPIO-AINTC";
557 irq_chip->irq_set_type = gpio_irq_type_unbanked;
558
559 /* default trigger: both edges */
560 g = gpio2regs(0);
561 writel_relaxed(~0, &g->set_falling);
562 writel_relaxed(~0, &g->set_rising);
563
564 /* set the direct IRQs up to use that irqchip */
565 for (gpio = 0; gpio < pdata->gpio_unbanked; gpio++, irq++) {
566 irq_set_chip(irq, irq_chip);
567 irq_set_handler_data(irq, &chips[gpio / 32]);
568 irq_set_status_flags(irq, IRQ_TYPE_EDGE_BOTH);
569 }
570
571 goto done;
572 }
573
574 /*
575 * Or, AINTC can handle IRQs for banks of 16 GPIO IRQs, which we
576 * then chain through our own handler.
577 */
578 for (gpio = 0, bank = 0; gpio < ngpio; bank++, bank_irq++, gpio += 16) {
579 /* disabled by default, enabled only as needed */
580 g = gpio2regs(gpio);
581 writel_relaxed(~0, &g->clr_falling);
582 writel_relaxed(~0, &g->clr_rising);
583
584 /*
585 * Each chip handles 32 gpios, and each irq bank consists of 16
586 * gpio irqs. Pass the irq bank's corresponding controller to
587 * the chained irq handler.
588 */
589 irq_set_chained_handler_and_data(bank_irq, gpio_irq_handler,
590 &chips[gpio / 32]);
591
592 binten |= BIT(bank);
593 }
594
595done:
596 /*
597 * BINTEN -- per-bank interrupt enable. genirq would also let these
598 * bits be set/cleared dynamically.
599 */
600 writel_relaxed(binten, gpio_base + BINTEN);
601
602 return 0;
603}
604
605#if IS_ENABLED(CONFIG_OF)
606static const struct of_device_id davinci_gpio_ids[] = {
607 { .compatible = "ti,keystone-gpio", keystone_gpio_get_irq_chip},
608 { .compatible = "ti,dm6441-gpio", davinci_gpio_get_irq_chip},
609 { /* sentinel */ },
610};
611MODULE_DEVICE_TABLE(of, davinci_gpio_ids);
612#endif
613
614static struct platform_driver davinci_gpio_driver = {
615 .probe = davinci_gpio_probe,
616 .driver = {
617 .name = "davinci_gpio",
618 .of_match_table = of_match_ptr(davinci_gpio_ids),
619 },
620};
621
622/**
623 * GPIO driver registration needs to be done before machine_init functions
624 * access GPIO. Hence davinci_gpio_drv_reg() is a postcore_initcall.
625 */
626static int __init davinci_gpio_drv_reg(void)
627{
628 return platform_driver_register(&davinci_gpio_driver);
629}
630postcore_initcall(davinci_gpio_drv_reg);