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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/of.h>
19#include <linux/of_device.h>
20#include <linux/pinctrl/consumer.h>
21#include <linux/platform_device.h>
22#include <linux/platform_data/gpio-davinci.h>
23#include <linux/irqchip/chained_irq.h>
24#include <linux/spinlock.h>
25#include <linux/pm_runtime.h>
26
27#include <asm-generic/gpio.h>
28
29#define MAX_REGS_BANKS 5
30#define MAX_INT_PER_BANK 32
31
32struct davinci_gpio_regs {
33 u32 dir;
34 u32 out_data;
35 u32 set_data;
36 u32 clr_data;
37 u32 in_data;
38 u32 set_rising;
39 u32 clr_rising;
40 u32 set_falling;
41 u32 clr_falling;
42 u32 intstat;
43};
44
45typedef struct irq_chip *(*gpio_get_irq_chip_cb_t)(unsigned int irq);
46
47#define BINTEN 0x8 /* GPIO Interrupt Per-Bank Enable Register */
48
49static void __iomem *gpio_base;
50static unsigned int offset_array[5] = {0x10, 0x38, 0x60, 0x88, 0xb0};
51
52struct davinci_gpio_irq_data {
53 void __iomem *regs;
54 struct davinci_gpio_controller *chip;
55 int bank_num;
56};
57
58struct davinci_gpio_controller {
59 struct gpio_chip chip;
60 struct irq_domain *irq_domain;
61 /* Serialize access to GPIO registers */
62 spinlock_t lock;
63 void __iomem *regs[MAX_REGS_BANKS];
64 int gpio_unbanked;
65 int irqs[MAX_INT_PER_BANK];
66 struct davinci_gpio_regs context[MAX_REGS_BANKS];
67 u32 binten_context;
68};
69
70static inline u32 __gpio_mask(unsigned gpio)
71{
72 return 1 << (gpio % 32);
73}
74
75static inline struct davinci_gpio_regs __iomem *irq2regs(struct irq_data *d)
76{
77 struct davinci_gpio_regs __iomem *g;
78
79 g = (__force struct davinci_gpio_regs __iomem *)irq_data_get_irq_chip_data(d);
80
81 return g;
82}
83
84static int davinci_gpio_irq_setup(struct platform_device *pdev);
85
86/*--------------------------------------------------------------------------*/
87
88/* board setup code *MUST* setup pinmux and enable the GPIO clock. */
89static inline int __davinci_direction(struct gpio_chip *chip,
90 unsigned offset, bool out, int value)
91{
92 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
93 struct davinci_gpio_regs __iomem *g;
94 unsigned long flags;
95 u32 temp;
96 int bank = offset / 32;
97 u32 mask = __gpio_mask(offset);
98
99 g = d->regs[bank];
100 spin_lock_irqsave(&d->lock, flags);
101 temp = readl_relaxed(&g->dir);
102 if (out) {
103 temp &= ~mask;
104 writel_relaxed(mask, value ? &g->set_data : &g->clr_data);
105 } else {
106 temp |= mask;
107 }
108 writel_relaxed(temp, &g->dir);
109 spin_unlock_irqrestore(&d->lock, flags);
110
111 return 0;
112}
113
114static int davinci_direction_in(struct gpio_chip *chip, unsigned offset)
115{
116 return __davinci_direction(chip, offset, false, 0);
117}
118
119static int
120davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value)
121{
122 return __davinci_direction(chip, offset, true, value);
123}
124
125/*
126 * Read the pin's value (works even if it's set up as output);
127 * returns zero/nonzero.
128 *
129 * Note that changes are synched to the GPIO clock, so reading values back
130 * right after you've set them may give old values.
131 */
132static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset)
133{
134 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
135 struct davinci_gpio_regs __iomem *g;
136 int bank = offset / 32;
137
138 g = d->regs[bank];
139
140 return !!(__gpio_mask(offset) & readl_relaxed(&g->in_data));
141}
142
143/*
144 * Assuming the pin is muxed as a gpio output, set its output value.
145 */
146static void
147davinci_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
148{
149 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
150 struct davinci_gpio_regs __iomem *g;
151 int bank = offset / 32;
152
153 g = d->regs[bank];
154
155 writel_relaxed(__gpio_mask(offset),
156 value ? &g->set_data : &g->clr_data);
157}
158
159static struct davinci_gpio_platform_data *
160davinci_gpio_get_pdata(struct platform_device *pdev)
161{
162 struct device_node *dn = pdev->dev.of_node;
163 struct davinci_gpio_platform_data *pdata;
164 int ret;
165 u32 val;
166
167 if (!IS_ENABLED(CONFIG_OF) || !pdev->dev.of_node)
168 return dev_get_platdata(&pdev->dev);
169
170 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
171 if (!pdata)
172 return NULL;
173
174 ret = of_property_read_u32(dn, "ti,ngpio", &val);
175 if (ret)
176 goto of_err;
177
178 pdata->ngpio = val;
179
180 ret = of_property_read_u32(dn, "ti,davinci-gpio-unbanked", &val);
181 if (ret)
182 goto of_err;
183
184 pdata->gpio_unbanked = val;
185
186 return pdata;
187
188of_err:
189 dev_err(&pdev->dev, "Populating pdata from DT failed: err %d\n", ret);
190 return NULL;
191}
192
193static int davinci_gpio_probe(struct platform_device *pdev)
194{
195 int bank, i, ret = 0;
196 unsigned int ngpio, nbank, nirq;
197 struct davinci_gpio_controller *chips;
198 struct davinci_gpio_platform_data *pdata;
199 struct device *dev = &pdev->dev;
200
201 pdata = davinci_gpio_get_pdata(pdev);
202 if (!pdata) {
203 dev_err(dev, "No platform data found\n");
204 return -EINVAL;
205 }
206
207 dev->platform_data = pdata;
208
209 /*
210 * The gpio banks conceptually expose a segmented bitmap,
211 * and "ngpio" is one more than the largest zero-based
212 * bit index that's valid.
213 */
214 ngpio = pdata->ngpio;
215 if (ngpio == 0) {
216 dev_err(dev, "How many GPIOs?\n");
217 return -EINVAL;
218 }
219
220 /*
221 * If there are unbanked interrupts then the number of
222 * interrupts is equal to number of gpios else all are banked so
223 * number of interrupts is equal to number of banks(each with 16 gpios)
224 */
225 if (pdata->gpio_unbanked)
226 nirq = pdata->gpio_unbanked;
227 else
228 nirq = DIV_ROUND_UP(ngpio, 16);
229
230 chips = devm_kzalloc(dev, sizeof(*chips), GFP_KERNEL);
231 if (!chips)
232 return -ENOMEM;
233
234 gpio_base = devm_platform_ioremap_resource(pdev, 0);
235 if (IS_ERR(gpio_base))
236 return PTR_ERR(gpio_base);
237
238 for (i = 0; i < nirq; i++) {
239 chips->irqs[i] = platform_get_irq(pdev, i);
240 if (chips->irqs[i] < 0)
241 return dev_err_probe(dev, chips->irqs[i], "IRQ not populated\n");
242 }
243
244 chips->chip.label = dev_name(dev);
245
246 chips->chip.direction_input = davinci_direction_in;
247 chips->chip.get = davinci_gpio_get;
248 chips->chip.direction_output = davinci_direction_out;
249 chips->chip.set = davinci_gpio_set;
250
251 chips->chip.ngpio = ngpio;
252 chips->chip.base = pdata->no_auto_base ? pdata->base : -1;
253
254#ifdef CONFIG_OF_GPIO
255 chips->chip.of_gpio_n_cells = 2;
256 chips->chip.parent = dev;
257 chips->chip.request = gpiochip_generic_request;
258 chips->chip.free = gpiochip_generic_free;
259#endif
260 spin_lock_init(&chips->lock);
261
262 nbank = DIV_ROUND_UP(ngpio, 32);
263 for (bank = 0; bank < nbank; bank++)
264 chips->regs[bank] = gpio_base + offset_array[bank];
265
266 ret = devm_gpiochip_add_data(dev, &chips->chip, chips);
267 if (ret)
268 return ret;
269
270 platform_set_drvdata(pdev, chips);
271 ret = davinci_gpio_irq_setup(pdev);
272 if (ret)
273 return ret;
274
275 return 0;
276}
277
278/*--------------------------------------------------------------------------*/
279/*
280 * We expect irqs will normally be set up as input pins, but they can also be
281 * used as output pins ... which is convenient for testing.
282 *
283 * NOTE: The first few GPIOs also have direct INTC hookups in addition
284 * to their GPIOBNK0 irq, with a bit less overhead.
285 *
286 * All those INTC hookups (direct, plus several IRQ banks) can also
287 * serve as EDMA event triggers.
288 */
289
290static void gpio_irq_disable(struct irq_data *d)
291{
292 struct davinci_gpio_regs __iomem *g = irq2regs(d);
293 uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d);
294
295 writel_relaxed(mask, &g->clr_falling);
296 writel_relaxed(mask, &g->clr_rising);
297}
298
299static void gpio_irq_enable(struct irq_data *d)
300{
301 struct davinci_gpio_regs __iomem *g = irq2regs(d);
302 uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d);
303 unsigned status = irqd_get_trigger_type(d);
304
305 status &= IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
306 if (!status)
307 status = IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
308
309 if (status & IRQ_TYPE_EDGE_FALLING)
310 writel_relaxed(mask, &g->set_falling);
311 if (status & IRQ_TYPE_EDGE_RISING)
312 writel_relaxed(mask, &g->set_rising);
313}
314
315static int gpio_irq_type(struct irq_data *d, unsigned trigger)
316{
317 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
318 return -EINVAL;
319
320 return 0;
321}
322
323static struct irq_chip gpio_irqchip = {
324 .name = "GPIO",
325 .irq_enable = gpio_irq_enable,
326 .irq_disable = gpio_irq_disable,
327 .irq_set_type = gpio_irq_type,
328 .flags = IRQCHIP_SET_TYPE_MASKED,
329};
330
331static void gpio_irq_handler(struct irq_desc *desc)
332{
333 struct davinci_gpio_regs __iomem *g;
334 u32 mask = 0xffff;
335 int bank_num;
336 struct davinci_gpio_controller *d;
337 struct davinci_gpio_irq_data *irqdata;
338
339 irqdata = (struct davinci_gpio_irq_data *)irq_desc_get_handler_data(desc);
340 bank_num = irqdata->bank_num;
341 g = irqdata->regs;
342 d = irqdata->chip;
343
344 /* we only care about one bank */
345 if ((bank_num % 2) == 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 irq_hw_number_t hw_irq;
354
355 /* ack any irqs */
356 status = readl_relaxed(&g->intstat) & mask;
357 if (!status)
358 break;
359 writel_relaxed(status, &g->intstat);
360
361 /* now demux them to the right lowlevel handler */
362
363 while (status) {
364 bit = __ffs(status);
365 status &= ~BIT(bit);
366 /* Max number of gpios per controller is 144 so
367 * hw_irq will be in [0..143]
368 */
369 hw_irq = (bank_num / 2) * 32 + bit;
370
371 generic_handle_domain_irq(d->irq_domain, hw_irq);
372 }
373 }
374 chained_irq_exit(irq_desc_get_chip(desc), desc);
375 /* now it may re-trigger */
376}
377
378static int gpio_to_irq_banked(struct gpio_chip *chip, unsigned offset)
379{
380 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
381
382 if (d->irq_domain)
383 return irq_create_mapping(d->irq_domain, offset);
384 else
385 return -ENXIO;
386}
387
388static int gpio_to_irq_unbanked(struct gpio_chip *chip, unsigned offset)
389{
390 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
391
392 /*
393 * NOTE: we assume for now that only irqs in the first gpio_chip
394 * can provide direct-mapped IRQs to AINTC (up to 32 GPIOs).
395 */
396 if (offset < d->gpio_unbanked)
397 return d->irqs[offset];
398 else
399 return -ENODEV;
400}
401
402static int gpio_irq_type_unbanked(struct irq_data *data, unsigned trigger)
403{
404 struct davinci_gpio_controller *d;
405 struct davinci_gpio_regs __iomem *g;
406 u32 mask, i;
407
408 d = (struct davinci_gpio_controller *)irq_data_get_irq_handler_data(data);
409 g = (struct davinci_gpio_regs __iomem *)d->regs[0];
410 for (i = 0; i < MAX_INT_PER_BANK; i++)
411 if (data->irq == d->irqs[i])
412 break;
413
414 if (i == MAX_INT_PER_BANK)
415 return -EINVAL;
416
417 mask = __gpio_mask(i);
418
419 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
420 return -EINVAL;
421
422 writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_FALLING)
423 ? &g->set_falling : &g->clr_falling);
424 writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_RISING)
425 ? &g->set_rising : &g->clr_rising);
426
427 return 0;
428}
429
430static int
431davinci_gpio_irq_map(struct irq_domain *d, unsigned int irq,
432 irq_hw_number_t hw)
433{
434 struct davinci_gpio_controller *chips =
435 (struct davinci_gpio_controller *)d->host_data;
436 struct davinci_gpio_regs __iomem *g = chips->regs[hw / 32];
437
438 irq_set_chip_and_handler_name(irq, &gpio_irqchip, handle_simple_irq,
439 "davinci_gpio");
440 irq_set_irq_type(irq, IRQ_TYPE_NONE);
441 irq_set_chip_data(irq, (__force void *)g);
442 irq_set_handler_data(irq, (void *)(uintptr_t)__gpio_mask(hw));
443
444 return 0;
445}
446
447static const struct irq_domain_ops davinci_gpio_irq_ops = {
448 .map = davinci_gpio_irq_map,
449 .xlate = irq_domain_xlate_onetwocell,
450};
451
452static struct irq_chip *davinci_gpio_get_irq_chip(unsigned int irq)
453{
454 static struct irq_chip_type gpio_unbanked;
455
456 gpio_unbanked = *irq_data_get_chip_type(irq_get_irq_data(irq));
457
458 return &gpio_unbanked.chip;
459};
460
461static struct irq_chip *keystone_gpio_get_irq_chip(unsigned int irq)
462{
463 static struct irq_chip gpio_unbanked;
464
465 gpio_unbanked = *irq_get_chip(irq);
466 return &gpio_unbanked;
467};
468
469static const struct of_device_id davinci_gpio_ids[];
470
471/*
472 * NOTE: for suspend/resume, probably best to make a platform_device with
473 * suspend_late/resume_resume calls hooking into results of the set_wake()
474 * calls ... so if no gpios are wakeup events the clock can be disabled,
475 * with outputs left at previously set levels, and so that VDD3P3V.IOPWDN0
476 * (dm6446) can be set appropriately for GPIOV33 pins.
477 */
478
479static int davinci_gpio_irq_setup(struct platform_device *pdev)
480{
481 unsigned gpio, bank;
482 int irq;
483 int ret;
484 struct clk *clk;
485 u32 binten = 0;
486 unsigned ngpio;
487 struct device *dev = &pdev->dev;
488 struct davinci_gpio_controller *chips = platform_get_drvdata(pdev);
489 struct davinci_gpio_platform_data *pdata = dev->platform_data;
490 struct davinci_gpio_regs __iomem *g;
491 struct irq_domain *irq_domain = NULL;
492 const struct of_device_id *match;
493 struct irq_chip *irq_chip;
494 struct davinci_gpio_irq_data *irqdata;
495 gpio_get_irq_chip_cb_t gpio_get_irq_chip;
496
497 /*
498 * Use davinci_gpio_get_irq_chip by default to handle non DT cases
499 */
500 gpio_get_irq_chip = davinci_gpio_get_irq_chip;
501 match = of_match_device(of_match_ptr(davinci_gpio_ids),
502 dev);
503 if (match)
504 gpio_get_irq_chip = (gpio_get_irq_chip_cb_t)match->data;
505
506 ngpio = pdata->ngpio;
507
508 clk = devm_clk_get(dev, "gpio");
509 if (IS_ERR(clk)) {
510 dev_err(dev, "Error %ld getting gpio clock\n", PTR_ERR(clk));
511 return PTR_ERR(clk);
512 }
513
514 ret = clk_prepare_enable(clk);
515 if (ret)
516 return ret;
517
518 if (!pdata->gpio_unbanked) {
519 irq = devm_irq_alloc_descs(dev, -1, 0, ngpio, 0);
520 if (irq < 0) {
521 dev_err(dev, "Couldn't allocate IRQ numbers\n");
522 clk_disable_unprepare(clk);
523 return irq;
524 }
525
526 irq_domain = irq_domain_add_legacy(dev->of_node, ngpio, irq, 0,
527 &davinci_gpio_irq_ops,
528 chips);
529 if (!irq_domain) {
530 dev_err(dev, "Couldn't register an IRQ domain\n");
531 clk_disable_unprepare(clk);
532 return -ENODEV;
533 }
534 }
535
536 /*
537 * Arrange gpio_to_irq() support, handling either direct IRQs or
538 * banked IRQs. Having GPIOs in the first GPIO bank use direct
539 * IRQs, while the others use banked IRQs, would need some setup
540 * tweaks to recognize hardware which can do that.
541 */
542 chips->chip.to_irq = gpio_to_irq_banked;
543 chips->irq_domain = irq_domain;
544
545 /*
546 * AINTC can handle direct/unbanked IRQs for GPIOs, with the GPIO
547 * controller only handling trigger modes. We currently assume no
548 * IRQ mux conflicts; gpio_irq_type_unbanked() is only for GPIOs.
549 */
550 if (pdata->gpio_unbanked) {
551 /* pass "bank 0" GPIO IRQs to AINTC */
552 chips->chip.to_irq = gpio_to_irq_unbanked;
553 chips->gpio_unbanked = pdata->gpio_unbanked;
554 binten = GENMASK(pdata->gpio_unbanked / 16, 0);
555
556 /* AINTC handles mask/unmask; GPIO handles triggering */
557 irq = chips->irqs[0];
558 irq_chip = gpio_get_irq_chip(irq);
559 irq_chip->name = "GPIO-AINTC";
560 irq_chip->irq_set_type = gpio_irq_type_unbanked;
561
562 /* default trigger: both edges */
563 g = chips->regs[0];
564 writel_relaxed(~0, &g->set_falling);
565 writel_relaxed(~0, &g->set_rising);
566
567 /* set the direct IRQs up to use that irqchip */
568 for (gpio = 0; gpio < pdata->gpio_unbanked; gpio++) {
569 irq_set_chip(chips->irqs[gpio], irq_chip);
570 irq_set_handler_data(chips->irqs[gpio], chips);
571 irq_set_status_flags(chips->irqs[gpio],
572 IRQ_TYPE_EDGE_BOTH);
573 }
574
575 goto done;
576 }
577
578 /*
579 * Or, AINTC can handle IRQs for banks of 16 GPIO IRQs, which we
580 * then chain through our own handler.
581 */
582 for (gpio = 0, bank = 0; gpio < ngpio; bank++, gpio += 16) {
583 /* disabled by default, enabled only as needed
584 * There are register sets for 32 GPIOs. 2 banks of 16
585 * GPIOs are covered by each set of registers hence divide by 2
586 */
587 g = chips->regs[bank / 2];
588 writel_relaxed(~0, &g->clr_falling);
589 writel_relaxed(~0, &g->clr_rising);
590
591 /*
592 * Each chip handles 32 gpios, and each irq bank consists of 16
593 * gpio irqs. Pass the irq bank's corresponding controller to
594 * the chained irq handler.
595 */
596 irqdata = devm_kzalloc(&pdev->dev,
597 sizeof(struct
598 davinci_gpio_irq_data),
599 GFP_KERNEL);
600 if (!irqdata) {
601 clk_disable_unprepare(clk);
602 return -ENOMEM;
603 }
604
605 irqdata->regs = g;
606 irqdata->bank_num = bank;
607 irqdata->chip = chips;
608
609 irq_set_chained_handler_and_data(chips->irqs[bank],
610 gpio_irq_handler, irqdata);
611
612 binten |= BIT(bank);
613 }
614
615done:
616 /*
617 * BINTEN -- per-bank interrupt enable. genirq would also let these
618 * bits be set/cleared dynamically.
619 */
620 writel_relaxed(binten, gpio_base + BINTEN);
621
622 return 0;
623}
624
625static void davinci_gpio_save_context(struct davinci_gpio_controller *chips,
626 u32 nbank)
627{
628 struct davinci_gpio_regs __iomem *g;
629 struct davinci_gpio_regs *context;
630 u32 bank;
631 void __iomem *base;
632
633 base = chips->regs[0] - offset_array[0];
634 chips->binten_context = readl_relaxed(base + BINTEN);
635
636 for (bank = 0; bank < nbank; bank++) {
637 g = chips->regs[bank];
638 context = &chips->context[bank];
639 context->dir = readl_relaxed(&g->dir);
640 context->set_data = readl_relaxed(&g->set_data);
641 context->set_rising = readl_relaxed(&g->set_rising);
642 context->set_falling = readl_relaxed(&g->set_falling);
643 }
644
645 /* Clear Bank interrupt enable bit */
646 writel_relaxed(0, base + BINTEN);
647
648 /* Clear all interrupt status registers */
649 writel_relaxed(GENMASK(31, 0), &g->intstat);
650}
651
652static void davinci_gpio_restore_context(struct davinci_gpio_controller *chips,
653 u32 nbank)
654{
655 struct davinci_gpio_regs __iomem *g;
656 struct davinci_gpio_regs *context;
657 u32 bank;
658 void __iomem *base;
659
660 base = chips->regs[0] - offset_array[0];
661
662 if (readl_relaxed(base + BINTEN) != chips->binten_context)
663 writel_relaxed(chips->binten_context, base + BINTEN);
664
665 for (bank = 0; bank < nbank; bank++) {
666 g = chips->regs[bank];
667 context = &chips->context[bank];
668 if (readl_relaxed(&g->dir) != context->dir)
669 writel_relaxed(context->dir, &g->dir);
670 if (readl_relaxed(&g->set_data) != context->set_data)
671 writel_relaxed(context->set_data, &g->set_data);
672 if (readl_relaxed(&g->set_rising) != context->set_rising)
673 writel_relaxed(context->set_rising, &g->set_rising);
674 if (readl_relaxed(&g->set_falling) != context->set_falling)
675 writel_relaxed(context->set_falling, &g->set_falling);
676 }
677}
678
679static int davinci_gpio_suspend(struct device *dev)
680{
681 struct davinci_gpio_controller *chips = dev_get_drvdata(dev);
682 struct davinci_gpio_platform_data *pdata = dev_get_platdata(dev);
683 u32 nbank = DIV_ROUND_UP(pdata->ngpio, 32);
684
685 davinci_gpio_save_context(chips, nbank);
686
687 return 0;
688}
689
690static int davinci_gpio_resume(struct device *dev)
691{
692 struct davinci_gpio_controller *chips = dev_get_drvdata(dev);
693 struct davinci_gpio_platform_data *pdata = dev_get_platdata(dev);
694 u32 nbank = DIV_ROUND_UP(pdata->ngpio, 32);
695
696 davinci_gpio_restore_context(chips, nbank);
697
698 return 0;
699}
700
701DEFINE_SIMPLE_DEV_PM_OPS(davinci_gpio_dev_pm_ops, davinci_gpio_suspend,
702 davinci_gpio_resume);
703
704static const struct of_device_id davinci_gpio_ids[] = {
705 { .compatible = "ti,keystone-gpio", keystone_gpio_get_irq_chip},
706 { .compatible = "ti,am654-gpio", keystone_gpio_get_irq_chip},
707 { .compatible = "ti,dm6441-gpio", davinci_gpio_get_irq_chip},
708 { /* sentinel */ },
709};
710MODULE_DEVICE_TABLE(of, davinci_gpio_ids);
711
712static struct platform_driver davinci_gpio_driver = {
713 .probe = davinci_gpio_probe,
714 .driver = {
715 .name = "davinci_gpio",
716 .pm = pm_sleep_ptr(&davinci_gpio_dev_pm_ops),
717 .of_match_table = of_match_ptr(davinci_gpio_ids),
718 },
719};
720
721/**
722 * GPIO driver registration needs to be done before machine_init functions
723 * access GPIO. Hence davinci_gpio_drv_reg() is a postcore_initcall.
724 */
725static int __init davinci_gpio_drv_reg(void)
726{
727 return platform_driver_register(&davinci_gpio_driver);
728}
729postcore_initcall(davinci_gpio_drv_reg);
730
731static void __exit davinci_gpio_exit(void)
732{
733 platform_driver_unregister(&davinci_gpio_driver);
734}
735module_exit(davinci_gpio_exit);
736
737MODULE_AUTHOR("Jan Kotas <jank@cadence.com>");
738MODULE_DESCRIPTION("DAVINCI GPIO driver");
739MODULE_LICENSE("GPL");
740MODULE_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/driver.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/pinctrl/consumer.h>
24#include <linux/platform_device.h>
25#include <linux/platform_data/gpio-davinci.h>
26#include <linux/irqchip/chained_irq.h>
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#define MAX_LABEL_SIZE 20
45
46static void __iomem *gpio_base;
47static unsigned int offset_array[5] = {0x10, 0x38, 0x60, 0x88, 0xb0};
48
49static inline struct davinci_gpio_regs __iomem *irq2regs(struct irq_data *d)
50{
51 struct davinci_gpio_regs __iomem *g;
52
53 g = (__force struct davinci_gpio_regs __iomem *)irq_data_get_irq_chip_data(d);
54
55 return g;
56}
57
58static int davinci_gpio_irq_setup(struct platform_device *pdev);
59
60/*--------------------------------------------------------------------------*/
61
62/* board setup code *MUST* setup pinmux and enable the GPIO clock. */
63static inline int __davinci_direction(struct gpio_chip *chip,
64 unsigned offset, bool out, int value)
65{
66 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
67 struct davinci_gpio_regs __iomem *g;
68 unsigned long flags;
69 u32 temp;
70 int bank = offset / 32;
71 u32 mask = __gpio_mask(offset);
72
73 g = d->regs[bank];
74 spin_lock_irqsave(&d->lock, flags);
75 temp = readl_relaxed(&g->dir);
76 if (out) {
77 temp &= ~mask;
78 writel_relaxed(mask, value ? &g->set_data : &g->clr_data);
79 } else {
80 temp |= mask;
81 }
82 writel_relaxed(temp, &g->dir);
83 spin_unlock_irqrestore(&d->lock, flags);
84
85 return 0;
86}
87
88static int davinci_direction_in(struct gpio_chip *chip, unsigned offset)
89{
90 return __davinci_direction(chip, offset, false, 0);
91}
92
93static int
94davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value)
95{
96 return __davinci_direction(chip, offset, true, value);
97}
98
99/*
100 * Read the pin's value (works even if it's set up as output);
101 * returns zero/nonzero.
102 *
103 * Note that changes are synched to the GPIO clock, so reading values back
104 * right after you've set them may give old values.
105 */
106static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset)
107{
108 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
109 struct davinci_gpio_regs __iomem *g;
110 int bank = offset / 32;
111
112 g = d->regs[bank];
113
114 return !!(__gpio_mask(offset) & readl_relaxed(&g->in_data));
115}
116
117/*
118 * Assuming the pin is muxed as a gpio output, set its output value.
119 */
120static void
121davinci_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
122{
123 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
124 struct davinci_gpio_regs __iomem *g;
125 int bank = offset / 32;
126
127 g = d->regs[bank];
128
129 writel_relaxed(__gpio_mask(offset),
130 value ? &g->set_data : &g->clr_data);
131}
132
133static struct davinci_gpio_platform_data *
134davinci_gpio_get_pdata(struct platform_device *pdev)
135{
136 struct device_node *dn = pdev->dev.of_node;
137 struct davinci_gpio_platform_data *pdata;
138 int ret;
139 u32 val;
140
141 if (!IS_ENABLED(CONFIG_OF) || !pdev->dev.of_node)
142 return dev_get_platdata(&pdev->dev);
143
144 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
145 if (!pdata)
146 return NULL;
147
148 ret = of_property_read_u32(dn, "ti,ngpio", &val);
149 if (ret)
150 goto of_err;
151
152 pdata->ngpio = val;
153
154 ret = of_property_read_u32(dn, "ti,davinci-gpio-unbanked", &val);
155 if (ret)
156 goto of_err;
157
158 pdata->gpio_unbanked = val;
159
160 return pdata;
161
162of_err:
163 dev_err(&pdev->dev, "Populating pdata from DT failed: err %d\n", ret);
164 return NULL;
165}
166
167static int davinci_gpio_probe(struct platform_device *pdev)
168{
169 static int ctrl_num, bank_base;
170 int gpio, bank, ret = 0;
171 unsigned ngpio, nbank;
172 struct davinci_gpio_controller *chips;
173 struct davinci_gpio_platform_data *pdata;
174 struct device *dev = &pdev->dev;
175 struct resource *res;
176 char label[MAX_LABEL_SIZE];
177
178 pdata = davinci_gpio_get_pdata(pdev);
179 if (!pdata) {
180 dev_err(dev, "No platform data found\n");
181 return -EINVAL;
182 }
183
184 dev->platform_data = pdata;
185
186 /*
187 * The gpio banks conceptually expose a segmented bitmap,
188 * and "ngpio" is one more than the largest zero-based
189 * bit index that's valid.
190 */
191 ngpio = pdata->ngpio;
192 if (ngpio == 0) {
193 dev_err(dev, "How many GPIOs?\n");
194 return -EINVAL;
195 }
196
197 if (WARN_ON(ARCH_NR_GPIOS < ngpio))
198 ngpio = ARCH_NR_GPIOS;
199
200 nbank = DIV_ROUND_UP(ngpio, 32);
201 chips = devm_kzalloc(dev,
202 nbank * sizeof(struct davinci_gpio_controller),
203 GFP_KERNEL);
204 if (!chips)
205 return -ENOMEM;
206
207 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
208 gpio_base = devm_ioremap_resource(dev, res);
209 if (IS_ERR(gpio_base))
210 return PTR_ERR(gpio_base);
211
212 snprintf(label, MAX_LABEL_SIZE, "davinci_gpio.%d", ctrl_num++);
213 chips->chip.label = devm_kstrdup(dev, label, GFP_KERNEL);
214 if (!chips->chip.label)
215 return -ENOMEM;
216
217 chips->chip.direction_input = davinci_direction_in;
218 chips->chip.get = davinci_gpio_get;
219 chips->chip.direction_output = davinci_direction_out;
220 chips->chip.set = davinci_gpio_set;
221
222 chips->chip.ngpio = ngpio;
223 chips->chip.base = bank_base;
224
225#ifdef CONFIG_OF_GPIO
226 chips->chip.of_gpio_n_cells = 2;
227 chips->chip.parent = dev;
228 chips->chip.of_node = dev->of_node;
229
230 if (of_property_read_bool(dev->of_node, "gpio-ranges")) {
231 chips->chip.request = gpiochip_generic_request;
232 chips->chip.free = gpiochip_generic_free;
233 }
234#endif
235 spin_lock_init(&chips->lock);
236 bank_base += ngpio;
237
238 for (gpio = 0, bank = 0; gpio < ngpio; gpio += 32, bank++)
239 chips->regs[bank] = gpio_base + offset_array[bank];
240
241 ret = devm_gpiochip_add_data(dev, &chips->chip, chips);
242 if (ret)
243 goto err;
244
245 platform_set_drvdata(pdev, chips);
246 ret = davinci_gpio_irq_setup(pdev);
247 if (ret)
248 goto err;
249
250 return 0;
251
252err:
253 /* Revert the static variable increments */
254 ctrl_num--;
255 bank_base -= ngpio;
256
257 return ret;
258}
259
260/*--------------------------------------------------------------------------*/
261/*
262 * We expect irqs will normally be set up as input pins, but they can also be
263 * used as output pins ... which is convenient for testing.
264 *
265 * NOTE: The first few GPIOs also have direct INTC hookups in addition
266 * to their GPIOBNK0 irq, with a bit less overhead.
267 *
268 * All those INTC hookups (direct, plus several IRQ banks) can also
269 * serve as EDMA event triggers.
270 */
271
272static void gpio_irq_disable(struct irq_data *d)
273{
274 struct davinci_gpio_regs __iomem *g = irq2regs(d);
275 u32 mask = (u32) irq_data_get_irq_handler_data(d);
276
277 writel_relaxed(mask, &g->clr_falling);
278 writel_relaxed(mask, &g->clr_rising);
279}
280
281static void gpio_irq_enable(struct irq_data *d)
282{
283 struct davinci_gpio_regs __iomem *g = irq2regs(d);
284 u32 mask = (u32) irq_data_get_irq_handler_data(d);
285 unsigned status = irqd_get_trigger_type(d);
286
287 status &= IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
288 if (!status)
289 status = IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
290
291 if (status & IRQ_TYPE_EDGE_FALLING)
292 writel_relaxed(mask, &g->set_falling);
293 if (status & IRQ_TYPE_EDGE_RISING)
294 writel_relaxed(mask, &g->set_rising);
295}
296
297static int gpio_irq_type(struct irq_data *d, unsigned trigger)
298{
299 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
300 return -EINVAL;
301
302 return 0;
303}
304
305static struct irq_chip gpio_irqchip = {
306 .name = "GPIO",
307 .irq_enable = gpio_irq_enable,
308 .irq_disable = gpio_irq_disable,
309 .irq_set_type = gpio_irq_type,
310 .flags = IRQCHIP_SET_TYPE_MASKED,
311};
312
313static void gpio_irq_handler(struct irq_desc *desc)
314{
315 struct davinci_gpio_regs __iomem *g;
316 u32 mask = 0xffff;
317 int bank_num;
318 struct davinci_gpio_controller *d;
319 struct davinci_gpio_irq_data *irqdata;
320
321 irqdata = (struct davinci_gpio_irq_data *)irq_desc_get_handler_data(desc);
322 bank_num = irqdata->bank_num;
323 g = irqdata->regs;
324 d = irqdata->chip;
325
326 /* we only care about one bank */
327 if ((bank_num % 2) == 1)
328 mask <<= 16;
329
330 /* temporarily mask (level sensitive) parent IRQ */
331 chained_irq_enter(irq_desc_get_chip(desc), desc);
332 while (1) {
333 u32 status;
334 int bit;
335 irq_hw_number_t hw_irq;
336
337 /* ack any irqs */
338 status = readl_relaxed(&g->intstat) & mask;
339 if (!status)
340 break;
341 writel_relaxed(status, &g->intstat);
342
343 /* now demux them to the right lowlevel handler */
344
345 while (status) {
346 bit = __ffs(status);
347 status &= ~BIT(bit);
348 /* Max number of gpios per controller is 144 so
349 * hw_irq will be in [0..143]
350 */
351 hw_irq = (bank_num / 2) * 32 + bit;
352
353 generic_handle_irq(
354 irq_find_mapping(d->irq_domain, hw_irq));
355 }
356 }
357 chained_irq_exit(irq_desc_get_chip(desc), desc);
358 /* now it may re-trigger */
359}
360
361static int gpio_to_irq_banked(struct gpio_chip *chip, unsigned offset)
362{
363 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
364
365 if (d->irq_domain)
366 return irq_create_mapping(d->irq_domain, offset);
367 else
368 return -ENXIO;
369}
370
371static int gpio_to_irq_unbanked(struct gpio_chip *chip, unsigned offset)
372{
373 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
374
375 /*
376 * NOTE: we assume for now that only irqs in the first gpio_chip
377 * can provide direct-mapped IRQs to AINTC (up to 32 GPIOs).
378 */
379 if (offset < d->gpio_unbanked)
380 return d->base_irq + offset;
381 else
382 return -ENODEV;
383}
384
385static int gpio_irq_type_unbanked(struct irq_data *data, unsigned trigger)
386{
387 struct davinci_gpio_controller *d;
388 struct davinci_gpio_regs __iomem *g;
389 u32 mask;
390
391 d = (struct davinci_gpio_controller *)irq_data_get_irq_handler_data(data);
392 g = (struct davinci_gpio_regs __iomem *)d->regs[0];
393 mask = __gpio_mask(data->irq - d->base_irq);
394
395 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
396 return -EINVAL;
397
398 writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_FALLING)
399 ? &g->set_falling : &g->clr_falling);
400 writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_RISING)
401 ? &g->set_rising : &g->clr_rising);
402
403 return 0;
404}
405
406static int
407davinci_gpio_irq_map(struct irq_domain *d, unsigned int irq,
408 irq_hw_number_t hw)
409{
410 struct davinci_gpio_controller *chips =
411 (struct davinci_gpio_controller *)d->host_data;
412 struct davinci_gpio_regs __iomem *g = chips->regs[hw / 32];
413
414 irq_set_chip_and_handler_name(irq, &gpio_irqchip, handle_simple_irq,
415 "davinci_gpio");
416 irq_set_irq_type(irq, IRQ_TYPE_NONE);
417 irq_set_chip_data(irq, (__force void *)g);
418 irq_set_handler_data(irq, (void *)__gpio_mask(hw));
419
420 return 0;
421}
422
423static const struct irq_domain_ops davinci_gpio_irq_ops = {
424 .map = davinci_gpio_irq_map,
425 .xlate = irq_domain_xlate_onetwocell,
426};
427
428static struct irq_chip *davinci_gpio_get_irq_chip(unsigned int irq)
429{
430 static struct irq_chip_type gpio_unbanked;
431
432 gpio_unbanked = *irq_data_get_chip_type(irq_get_irq_data(irq));
433
434 return &gpio_unbanked.chip;
435};
436
437static struct irq_chip *keystone_gpio_get_irq_chip(unsigned int irq)
438{
439 static struct irq_chip gpio_unbanked;
440
441 gpio_unbanked = *irq_get_chip(irq);
442 return &gpio_unbanked;
443};
444
445static const struct of_device_id davinci_gpio_ids[];
446
447/*
448 * NOTE: for suspend/resume, probably best to make a platform_device with
449 * suspend_late/resume_resume calls hooking into results of the set_wake()
450 * calls ... so if no gpios are wakeup events the clock can be disabled,
451 * with outputs left at previously set levels, and so that VDD3P3V.IOPWDN0
452 * (dm6446) can be set appropriately for GPIOV33 pins.
453 */
454
455static int davinci_gpio_irq_setup(struct platform_device *pdev)
456{
457 unsigned gpio, bank;
458 int irq;
459 int ret;
460 struct clk *clk;
461 u32 binten = 0;
462 unsigned ngpio, bank_irq;
463 struct device *dev = &pdev->dev;
464 struct resource *res;
465 struct davinci_gpio_controller *chips = platform_get_drvdata(pdev);
466 struct davinci_gpio_platform_data *pdata = dev->platform_data;
467 struct davinci_gpio_regs __iomem *g;
468 struct irq_domain *irq_domain = NULL;
469 const struct of_device_id *match;
470 struct irq_chip *irq_chip;
471 struct davinci_gpio_irq_data *irqdata;
472 gpio_get_irq_chip_cb_t gpio_get_irq_chip;
473
474 /*
475 * Use davinci_gpio_get_irq_chip by default to handle non DT cases
476 */
477 gpio_get_irq_chip = davinci_gpio_get_irq_chip;
478 match = of_match_device(of_match_ptr(davinci_gpio_ids),
479 dev);
480 if (match)
481 gpio_get_irq_chip = (gpio_get_irq_chip_cb_t)match->data;
482
483 ngpio = pdata->ngpio;
484 res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
485 if (!res) {
486 dev_err(dev, "Invalid IRQ resource\n");
487 return -EBUSY;
488 }
489
490 bank_irq = res->start;
491
492 if (!bank_irq) {
493 dev_err(dev, "Invalid IRQ resource\n");
494 return -ENODEV;
495 }
496
497 clk = devm_clk_get(dev, "gpio");
498 if (IS_ERR(clk)) {
499 dev_err(dev, "Error %ld getting gpio clock\n", PTR_ERR(clk));
500 return PTR_ERR(clk);
501 }
502 ret = clk_prepare_enable(clk);
503 if (ret)
504 return ret;
505
506 if (!pdata->gpio_unbanked) {
507 irq = devm_irq_alloc_descs(dev, -1, 0, ngpio, 0);
508 if (irq < 0) {
509 dev_err(dev, "Couldn't allocate IRQ numbers\n");
510 clk_disable_unprepare(clk);
511 return irq;
512 }
513
514 irq_domain = irq_domain_add_legacy(dev->of_node, ngpio, irq, 0,
515 &davinci_gpio_irq_ops,
516 chips);
517 if (!irq_domain) {
518 dev_err(dev, "Couldn't register an IRQ domain\n");
519 clk_disable_unprepare(clk);
520 return -ENODEV;
521 }
522 }
523
524 /*
525 * Arrange gpio_to_irq() support, handling either direct IRQs or
526 * banked IRQs. Having GPIOs in the first GPIO bank use direct
527 * IRQs, while the others use banked IRQs, would need some setup
528 * tweaks to recognize hardware which can do that.
529 */
530 chips->chip.to_irq = gpio_to_irq_banked;
531 chips->irq_domain = irq_domain;
532
533 /*
534 * AINTC can handle direct/unbanked IRQs for GPIOs, with the GPIO
535 * controller only handling trigger modes. We currently assume no
536 * IRQ mux conflicts; gpio_irq_type_unbanked() is only for GPIOs.
537 */
538 if (pdata->gpio_unbanked) {
539 /* pass "bank 0" GPIO IRQs to AINTC */
540 chips->chip.to_irq = gpio_to_irq_unbanked;
541 chips->base_irq = bank_irq;
542 chips->gpio_unbanked = pdata->gpio_unbanked;
543 binten = GENMASK(pdata->gpio_unbanked / 16, 0);
544
545 /* AINTC handles mask/unmask; GPIO handles triggering */
546 irq = bank_irq;
547 irq_chip = gpio_get_irq_chip(irq);
548 irq_chip->name = "GPIO-AINTC";
549 irq_chip->irq_set_type = gpio_irq_type_unbanked;
550
551 /* default trigger: both edges */
552 g = chips->regs[0];
553 writel_relaxed(~0, &g->set_falling);
554 writel_relaxed(~0, &g->set_rising);
555
556 /* set the direct IRQs up to use that irqchip */
557 for (gpio = 0; gpio < pdata->gpio_unbanked; gpio++, irq++) {
558 irq_set_chip(irq, irq_chip);
559 irq_set_handler_data(irq, chips);
560 irq_set_status_flags(irq, IRQ_TYPE_EDGE_BOTH);
561 }
562
563 goto done;
564 }
565
566 /*
567 * Or, AINTC can handle IRQs for banks of 16 GPIO IRQs, which we
568 * then chain through our own handler.
569 */
570 for (gpio = 0, bank = 0; gpio < ngpio; bank++, bank_irq++, gpio += 16) {
571 /* disabled by default, enabled only as needed
572 * There are register sets for 32 GPIOs. 2 banks of 16
573 * GPIOs are covered by each set of registers hence divide by 2
574 */
575 g = chips->regs[bank / 2];
576 writel_relaxed(~0, &g->clr_falling);
577 writel_relaxed(~0, &g->clr_rising);
578
579 /*
580 * Each chip handles 32 gpios, and each irq bank consists of 16
581 * gpio irqs. Pass the irq bank's corresponding controller to
582 * the chained irq handler.
583 */
584 irqdata = devm_kzalloc(&pdev->dev,
585 sizeof(struct
586 davinci_gpio_irq_data),
587 GFP_KERNEL);
588 if (!irqdata) {
589 clk_disable_unprepare(clk);
590 return -ENOMEM;
591 }
592
593 irqdata->regs = g;
594 irqdata->bank_num = bank;
595 irqdata->chip = chips;
596
597 irq_set_chained_handler_and_data(bank_irq, gpio_irq_handler,
598 irqdata);
599
600 binten |= BIT(bank);
601 }
602
603done:
604 /*
605 * BINTEN -- per-bank interrupt enable. genirq would also let these
606 * bits be set/cleared dynamically.
607 */
608 writel_relaxed(binten, gpio_base + BINTEN);
609
610 return 0;
611}
612
613#if IS_ENABLED(CONFIG_OF)
614static const struct of_device_id davinci_gpio_ids[] = {
615 { .compatible = "ti,keystone-gpio", keystone_gpio_get_irq_chip},
616 { .compatible = "ti,dm6441-gpio", davinci_gpio_get_irq_chip},
617 { /* sentinel */ },
618};
619MODULE_DEVICE_TABLE(of, davinci_gpio_ids);
620#endif
621
622static struct platform_driver davinci_gpio_driver = {
623 .probe = davinci_gpio_probe,
624 .driver = {
625 .name = "davinci_gpio",
626 .of_match_table = of_match_ptr(davinci_gpio_ids),
627 },
628};
629
630/**
631 * GPIO driver registration needs to be done before machine_init functions
632 * access GPIO. Hence davinci_gpio_drv_reg() is a postcore_initcall.
633 */
634static int __init davinci_gpio_drv_reg(void)
635{
636 return platform_driver_register(&davinci_gpio_driver);
637}
638postcore_initcall(davinci_gpio_drv_reg);