Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / drivers / pinctrl / spear / pinctrl-plgpio.c
blobd2123e396b29c8e7bd8557dc623a496f19faa3d7
1 /*
2 * SPEAr platform PLGPIO driver
4 * Copyright (C) 2012 ST Microelectronics
5 * Viresh Kumar <viresh.kumar@linaro.org>
7 * This file is licensed under the terms of the GNU General Public
8 * License version 2. This program is licensed "as is" without any
9 * warranty of any kind, whether express or implied.
12 #include <linux/clk.h>
13 #include <linux/err.h>
14 #include <linux/gpio/driver.h>
15 #include <linux/io.h>
16 #include <linux/init.h>
17 #include <linux/of.h>
18 #include <linux/of_platform.h>
19 #include <linux/pinctrl/consumer.h>
20 #include <linux/platform_device.h>
21 #include <linux/pm.h>
22 #include <linux/spinlock.h>
24 #define MAX_GPIO_PER_REG 32
25 #define PIN_OFFSET(pin) (pin % MAX_GPIO_PER_REG)
26 #define REG_OFFSET(base, reg, pin) (base + reg + (pin / MAX_GPIO_PER_REG) \
27 * sizeof(int *))
30 * plgpio pins in all machines are not one to one mapped, bitwise with registers
31 * bits. These set of macros define register masks for which below functions
32 * (pin_to_offset and offset_to_pin) are required to be called.
34 #define PTO_ENB_REG 0x001
35 #define PTO_WDATA_REG 0x002
36 #define PTO_DIR_REG 0x004
37 #define PTO_IE_REG 0x008
38 #define PTO_RDATA_REG 0x010
39 #define PTO_MIS_REG 0x020
41 struct plgpio_regs {
42 u32 enb; /* enable register */
43 u32 wdata; /* write data register */
44 u32 dir; /* direction set register */
45 u32 rdata; /* read data register */
46 u32 ie; /* interrupt enable register */
47 u32 mis; /* mask interrupt status register */
48 u32 eit; /* edge interrupt type */
52 * struct plgpio: plgpio driver specific structure
54 * lock: lock for guarding gpio registers
55 * base: base address of plgpio block
56 * chip: gpio framework specific chip information structure
57 * p2o: function ptr for pin to offset conversion. This is required only for
58 * machines where mapping b/w pin and offset is not 1-to-1.
59 * o2p: function ptr for offset to pin conversion. This is required only for
60 * machines where mapping b/w pin and offset is not 1-to-1.
61 * p2o_regs: mask of registers for which p2o and o2p are applicable
62 * regs: register offsets
63 * csave_regs: context save registers for standby/sleep/hibernate cases
65 struct plgpio {
66 spinlock_t lock;
67 void __iomem *base;
68 struct clk *clk;
69 struct gpio_chip chip;
70 int (*p2o)(int pin); /* pin_to_offset */
71 int (*o2p)(int offset); /* offset_to_pin */
72 u32 p2o_regs;
73 struct plgpio_regs regs;
74 #ifdef CONFIG_PM_SLEEP
75 struct plgpio_regs *csave_regs;
76 #endif
79 /* register manipulation inline functions */
80 static inline u32 is_plgpio_set(void __iomem *base, u32 pin, u32 reg)
82 u32 offset = PIN_OFFSET(pin);
83 void __iomem *reg_off = REG_OFFSET(base, reg, pin);
84 u32 val = readl_relaxed(reg_off);
86 return !!(val & (1 << offset));
89 static inline void plgpio_reg_set(void __iomem *base, u32 pin, u32 reg)
91 u32 offset = PIN_OFFSET(pin);
92 void __iomem *reg_off = REG_OFFSET(base, reg, pin);
93 u32 val = readl_relaxed(reg_off);
95 writel_relaxed(val | (1 << offset), reg_off);
98 static inline void plgpio_reg_reset(void __iomem *base, u32 pin, u32 reg)
100 u32 offset = PIN_OFFSET(pin);
101 void __iomem *reg_off = REG_OFFSET(base, reg, pin);
102 u32 val = readl_relaxed(reg_off);
104 writel_relaxed(val & ~(1 << offset), reg_off);
107 /* gpio framework specific routines */
108 static int plgpio_direction_input(struct gpio_chip *chip, unsigned offset)
110 struct plgpio *plgpio = gpiochip_get_data(chip);
111 unsigned long flags;
113 /* get correct offset for "offset" pin */
114 if (plgpio->p2o && (plgpio->p2o_regs & PTO_DIR_REG)) {
115 offset = plgpio->p2o(offset);
116 if (offset == -1)
117 return -EINVAL;
120 spin_lock_irqsave(&plgpio->lock, flags);
121 plgpio_reg_set(plgpio->base, offset, plgpio->regs.dir);
122 spin_unlock_irqrestore(&plgpio->lock, flags);
124 return 0;
127 static int plgpio_direction_output(struct gpio_chip *chip, unsigned offset,
128 int value)
130 struct plgpio *plgpio = gpiochip_get_data(chip);
131 unsigned long flags;
132 unsigned dir_offset = offset, wdata_offset = offset, tmp;
134 /* get correct offset for "offset" pin */
135 if (plgpio->p2o && (plgpio->p2o_regs & (PTO_DIR_REG | PTO_WDATA_REG))) {
136 tmp = plgpio->p2o(offset);
137 if (tmp == -1)
138 return -EINVAL;
140 if (plgpio->p2o_regs & PTO_DIR_REG)
141 dir_offset = tmp;
142 if (plgpio->p2o_regs & PTO_WDATA_REG)
143 wdata_offset = tmp;
146 spin_lock_irqsave(&plgpio->lock, flags);
147 if (value)
148 plgpio_reg_set(plgpio->base, wdata_offset,
149 plgpio->regs.wdata);
150 else
151 plgpio_reg_reset(plgpio->base, wdata_offset,
152 plgpio->regs.wdata);
154 plgpio_reg_reset(plgpio->base, dir_offset, plgpio->regs.dir);
155 spin_unlock_irqrestore(&plgpio->lock, flags);
157 return 0;
160 static int plgpio_get_value(struct gpio_chip *chip, unsigned offset)
162 struct plgpio *plgpio = gpiochip_get_data(chip);
164 if (offset >= chip->ngpio)
165 return -EINVAL;
167 /* get correct offset for "offset" pin */
168 if (plgpio->p2o && (plgpio->p2o_regs & PTO_RDATA_REG)) {
169 offset = plgpio->p2o(offset);
170 if (offset == -1)
171 return -EINVAL;
174 return is_plgpio_set(plgpio->base, offset, plgpio->regs.rdata);
177 static void plgpio_set_value(struct gpio_chip *chip, unsigned offset, int value)
179 struct plgpio *plgpio = gpiochip_get_data(chip);
181 if (offset >= chip->ngpio)
182 return;
184 /* get correct offset for "offset" pin */
185 if (plgpio->p2o && (plgpio->p2o_regs & PTO_WDATA_REG)) {
186 offset = plgpio->p2o(offset);
187 if (offset == -1)
188 return;
191 if (value)
192 plgpio_reg_set(plgpio->base, offset, plgpio->regs.wdata);
193 else
194 plgpio_reg_reset(plgpio->base, offset, plgpio->regs.wdata);
197 static int plgpio_request(struct gpio_chip *chip, unsigned offset)
199 struct plgpio *plgpio = gpiochip_get_data(chip);
200 int gpio = chip->base + offset;
201 unsigned long flags;
202 int ret = 0;
204 if (offset >= chip->ngpio)
205 return -EINVAL;
207 ret = pinctrl_gpio_request(gpio);
208 if (ret)
209 return ret;
211 if (!IS_ERR(plgpio->clk)) {
212 ret = clk_enable(plgpio->clk);
213 if (ret)
214 goto err0;
217 if (plgpio->regs.enb == -1)
218 return 0;
221 * put gpio in IN mode before enabling it. This make enabling gpio safe
223 ret = plgpio_direction_input(chip, offset);
224 if (ret)
225 goto err1;
227 /* get correct offset for "offset" pin */
228 if (plgpio->p2o && (plgpio->p2o_regs & PTO_ENB_REG)) {
229 offset = plgpio->p2o(offset);
230 if (offset == -1) {
231 ret = -EINVAL;
232 goto err1;
236 spin_lock_irqsave(&plgpio->lock, flags);
237 plgpio_reg_set(plgpio->base, offset, plgpio->regs.enb);
238 spin_unlock_irqrestore(&plgpio->lock, flags);
239 return 0;
241 err1:
242 if (!IS_ERR(plgpio->clk))
243 clk_disable(plgpio->clk);
244 err0:
245 pinctrl_gpio_free(gpio);
246 return ret;
249 static void plgpio_free(struct gpio_chip *chip, unsigned offset)
251 struct plgpio *plgpio = gpiochip_get_data(chip);
252 int gpio = chip->base + offset;
253 unsigned long flags;
255 if (offset >= chip->ngpio)
256 return;
258 if (plgpio->regs.enb == -1)
259 goto disable_clk;
261 /* get correct offset for "offset" pin */
262 if (plgpio->p2o && (plgpio->p2o_regs & PTO_ENB_REG)) {
263 offset = plgpio->p2o(offset);
264 if (offset == -1)
265 return;
268 spin_lock_irqsave(&plgpio->lock, flags);
269 plgpio_reg_reset(plgpio->base, offset, plgpio->regs.enb);
270 spin_unlock_irqrestore(&plgpio->lock, flags);
272 disable_clk:
273 if (!IS_ERR(plgpio->clk))
274 clk_disable(plgpio->clk);
276 pinctrl_gpio_free(gpio);
279 /* PLGPIO IRQ */
280 static void plgpio_irq_disable(struct irq_data *d)
282 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
283 struct plgpio *plgpio = gpiochip_get_data(gc);
284 int offset = d->hwirq;
285 unsigned long flags;
287 /* get correct offset for "offset" pin */
288 if (plgpio->p2o && (plgpio->p2o_regs & PTO_IE_REG)) {
289 offset = plgpio->p2o(offset);
290 if (offset == -1)
291 return;
294 spin_lock_irqsave(&plgpio->lock, flags);
295 plgpio_reg_set(plgpio->base, offset, plgpio->regs.ie);
296 spin_unlock_irqrestore(&plgpio->lock, flags);
299 static void plgpio_irq_enable(struct irq_data *d)
301 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
302 struct plgpio *plgpio = gpiochip_get_data(gc);
303 int offset = d->hwirq;
304 unsigned long flags;
306 /* get correct offset for "offset" pin */
307 if (plgpio->p2o && (plgpio->p2o_regs & PTO_IE_REG)) {
308 offset = plgpio->p2o(offset);
309 if (offset == -1)
310 return;
313 spin_lock_irqsave(&plgpio->lock, flags);
314 plgpio_reg_reset(plgpio->base, offset, plgpio->regs.ie);
315 spin_unlock_irqrestore(&plgpio->lock, flags);
318 static int plgpio_irq_set_type(struct irq_data *d, unsigned trigger)
320 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
321 struct plgpio *plgpio = gpiochip_get_data(gc);
322 int offset = d->hwirq;
323 void __iomem *reg_off;
324 unsigned int supported_type = 0, val;
326 if (offset >= plgpio->chip.ngpio)
327 return -EINVAL;
329 if (plgpio->regs.eit == -1)
330 supported_type = IRQ_TYPE_LEVEL_HIGH;
331 else
332 supported_type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
334 if (!(trigger & supported_type))
335 return -EINVAL;
337 if (plgpio->regs.eit == -1)
338 return 0;
340 reg_off = REG_OFFSET(plgpio->base, plgpio->regs.eit, offset);
341 val = readl_relaxed(reg_off);
343 offset = PIN_OFFSET(offset);
344 if (trigger & IRQ_TYPE_EDGE_RISING)
345 writel_relaxed(val | (1 << offset), reg_off);
346 else
347 writel_relaxed(val & ~(1 << offset), reg_off);
349 return 0;
352 static struct irq_chip plgpio_irqchip = {
353 .name = "PLGPIO",
354 .irq_enable = plgpio_irq_enable,
355 .irq_disable = plgpio_irq_disable,
356 .irq_set_type = plgpio_irq_set_type,
359 static void plgpio_irq_handler(struct irq_desc *desc)
361 struct gpio_chip *gc = irq_desc_get_handler_data(desc);
362 struct plgpio *plgpio = gpiochip_get_data(gc);
363 struct irq_chip *irqchip = irq_desc_get_chip(desc);
364 int regs_count, count, pin, offset, i = 0;
365 unsigned long pending;
367 count = plgpio->chip.ngpio;
368 regs_count = DIV_ROUND_UP(count, MAX_GPIO_PER_REG);
370 chained_irq_enter(irqchip, desc);
371 /* check all plgpio MIS registers for a possible interrupt */
372 for (; i < regs_count; i++) {
373 pending = readl_relaxed(plgpio->base + plgpio->regs.mis +
374 i * sizeof(int *));
375 if (!pending)
376 continue;
378 /* clear interrupts */
379 writel_relaxed(~pending, plgpio->base + plgpio->regs.mis +
380 i * sizeof(int *));
382 * clear extra bits in last register having gpios < MAX/REG
383 * ex: Suppose there are max 102 plgpios. then last register
384 * must have only (102 - MAX_GPIO_PER_REG * 3) = 6 relevant bits
385 * so, we must not take other 28 bits into consideration for
386 * checking interrupt. so clear those bits.
388 count = count - i * MAX_GPIO_PER_REG;
389 if (count < MAX_GPIO_PER_REG)
390 pending &= (1 << count) - 1;
392 for_each_set_bit(offset, &pending, MAX_GPIO_PER_REG) {
393 /* get correct pin for "offset" */
394 if (plgpio->o2p && (plgpio->p2o_regs & PTO_MIS_REG)) {
395 pin = plgpio->o2p(offset);
396 if (pin == -1)
397 continue;
398 } else
399 pin = offset;
401 /* get correct irq line number */
402 pin = i * MAX_GPIO_PER_REG + pin;
403 generic_handle_irq(
404 irq_find_mapping(gc->irq.domain, pin));
407 chained_irq_exit(irqchip, desc);
411 * pin to offset and offset to pin converter functions
413 * In spear310 there is inconsistency among bit positions in plgpio regiseters,
414 * for different plgpio pins. For example: for pin 27, bit offset is 23, pin
415 * 28-33 are not supported, pin 95 has offset bit 95, bit 100 has offset bit 1
417 static int spear310_p2o(int pin)
419 int offset = pin;
421 if (pin <= 27)
422 offset += 4;
423 else if (pin <= 33)
424 offset = -1;
425 else if (pin <= 97)
426 offset -= 2;
427 else if (pin <= 101)
428 offset = 101 - pin;
429 else
430 offset = -1;
432 return offset;
435 static int spear310_o2p(int offset)
437 if (offset <= 3)
438 return 101 - offset;
439 else if (offset <= 31)
440 return offset - 4;
441 else
442 return offset + 2;
445 static int plgpio_probe_dt(struct platform_device *pdev, struct plgpio *plgpio)
447 struct device_node *np = pdev->dev.of_node;
448 int ret = -EINVAL;
449 u32 val;
451 if (of_machine_is_compatible("st,spear310")) {
452 plgpio->p2o = spear310_p2o;
453 plgpio->o2p = spear310_o2p;
454 plgpio->p2o_regs = PTO_WDATA_REG | PTO_DIR_REG | PTO_IE_REG |
455 PTO_RDATA_REG | PTO_MIS_REG;
458 if (!of_property_read_u32(np, "st-plgpio,ngpio", &val)) {
459 plgpio->chip.ngpio = val;
460 } else {
461 dev_err(&pdev->dev, "DT: Invalid ngpio field\n");
462 goto end;
465 if (!of_property_read_u32(np, "st-plgpio,enb-reg", &val))
466 plgpio->regs.enb = val;
467 else
468 plgpio->regs.enb = -1;
470 if (!of_property_read_u32(np, "st-plgpio,wdata-reg", &val)) {
471 plgpio->regs.wdata = val;
472 } else {
473 dev_err(&pdev->dev, "DT: Invalid wdata reg\n");
474 goto end;
477 if (!of_property_read_u32(np, "st-plgpio,dir-reg", &val)) {
478 plgpio->regs.dir = val;
479 } else {
480 dev_err(&pdev->dev, "DT: Invalid dir reg\n");
481 goto end;
484 if (!of_property_read_u32(np, "st-plgpio,ie-reg", &val)) {
485 plgpio->regs.ie = val;
486 } else {
487 dev_err(&pdev->dev, "DT: Invalid ie reg\n");
488 goto end;
491 if (!of_property_read_u32(np, "st-plgpio,rdata-reg", &val)) {
492 plgpio->regs.rdata = val;
493 } else {
494 dev_err(&pdev->dev, "DT: Invalid rdata reg\n");
495 goto end;
498 if (!of_property_read_u32(np, "st-plgpio,mis-reg", &val)) {
499 plgpio->regs.mis = val;
500 } else {
501 dev_err(&pdev->dev, "DT: Invalid mis reg\n");
502 goto end;
505 if (!of_property_read_u32(np, "st-plgpio,eit-reg", &val))
506 plgpio->regs.eit = val;
507 else
508 plgpio->regs.eit = -1;
510 return 0;
512 end:
513 return ret;
515 static int plgpio_probe(struct platform_device *pdev)
517 struct plgpio *plgpio;
518 struct resource *res;
519 int ret, irq;
521 plgpio = devm_kzalloc(&pdev->dev, sizeof(*plgpio), GFP_KERNEL);
522 if (!plgpio)
523 return -ENOMEM;
525 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
526 plgpio->base = devm_ioremap_resource(&pdev->dev, res);
527 if (IS_ERR(plgpio->base))
528 return PTR_ERR(plgpio->base);
530 ret = plgpio_probe_dt(pdev, plgpio);
531 if (ret) {
532 dev_err(&pdev->dev, "DT probe failed\n");
533 return ret;
536 plgpio->clk = devm_clk_get(&pdev->dev, NULL);
537 if (IS_ERR(plgpio->clk))
538 dev_warn(&pdev->dev, "clk_get() failed, work without it\n");
540 #ifdef CONFIG_PM_SLEEP
541 plgpio->csave_regs = devm_kzalloc(&pdev->dev,
542 sizeof(*plgpio->csave_regs) *
543 DIV_ROUND_UP(plgpio->chip.ngpio, MAX_GPIO_PER_REG),
544 GFP_KERNEL);
545 if (!plgpio->csave_regs)
546 return -ENOMEM;
547 #endif
549 platform_set_drvdata(pdev, plgpio);
550 spin_lock_init(&plgpio->lock);
552 plgpio->chip.base = -1;
553 plgpio->chip.request = plgpio_request;
554 plgpio->chip.free = plgpio_free;
555 plgpio->chip.direction_input = plgpio_direction_input;
556 plgpio->chip.direction_output = plgpio_direction_output;
557 plgpio->chip.get = plgpio_get_value;
558 plgpio->chip.set = plgpio_set_value;
559 plgpio->chip.label = dev_name(&pdev->dev);
560 plgpio->chip.parent = &pdev->dev;
561 plgpio->chip.owner = THIS_MODULE;
562 plgpio->chip.of_node = pdev->dev.of_node;
564 if (!IS_ERR(plgpio->clk)) {
565 ret = clk_prepare(plgpio->clk);
566 if (ret) {
567 dev_err(&pdev->dev, "clk prepare failed\n");
568 return ret;
572 ret = gpiochip_add_data(&plgpio->chip, plgpio);
573 if (ret) {
574 dev_err(&pdev->dev, "unable to add gpio chip\n");
575 goto unprepare_clk;
578 irq = platform_get_irq(pdev, 0);
579 if (irq < 0) {
580 dev_info(&pdev->dev, "PLGPIO registered without IRQs\n");
581 return 0;
584 ret = gpiochip_irqchip_add(&plgpio->chip,
585 &plgpio_irqchip,
587 handle_simple_irq,
588 IRQ_TYPE_NONE);
589 if (ret) {
590 dev_err(&pdev->dev, "failed to add irqchip to gpiochip\n");
591 goto remove_gpiochip;
594 gpiochip_set_chained_irqchip(&plgpio->chip,
595 &plgpio_irqchip,
596 irq,
597 plgpio_irq_handler);
599 dev_info(&pdev->dev, "PLGPIO registered with IRQs\n");
601 return 0;
603 remove_gpiochip:
604 dev_info(&pdev->dev, "Remove gpiochip\n");
605 gpiochip_remove(&plgpio->chip);
606 unprepare_clk:
607 if (!IS_ERR(plgpio->clk))
608 clk_unprepare(plgpio->clk);
610 return ret;
613 #ifdef CONFIG_PM_SLEEP
614 static int plgpio_suspend(struct device *dev)
616 struct plgpio *plgpio = dev_get_drvdata(dev);
617 int i, reg_count = DIV_ROUND_UP(plgpio->chip.ngpio, MAX_GPIO_PER_REG);
618 void __iomem *off;
620 for (i = 0; i < reg_count; i++) {
621 off = plgpio->base + i * sizeof(int *);
623 if (plgpio->regs.enb != -1)
624 plgpio->csave_regs[i].enb =
625 readl_relaxed(plgpio->regs.enb + off);
626 if (plgpio->regs.eit != -1)
627 plgpio->csave_regs[i].eit =
628 readl_relaxed(plgpio->regs.eit + off);
629 plgpio->csave_regs[i].wdata = readl_relaxed(plgpio->regs.wdata +
630 off);
631 plgpio->csave_regs[i].dir = readl_relaxed(plgpio->regs.dir +
632 off);
633 plgpio->csave_regs[i].ie = readl_relaxed(plgpio->regs.ie + off);
636 return 0;
640 * This is used to correct the values in end registers. End registers contain
641 * extra bits that might be used for other purpose in platform. So, we shouldn't
642 * overwrite these bits. This macro, reads given register again, preserves other
643 * bit values (non-plgpio bits), and retain captured value (plgpio bits).
645 #define plgpio_prepare_reg(__reg, _off, _mask, _tmp) \
647 _tmp = readl_relaxed(plgpio->regs.__reg + _off); \
648 _tmp &= ~_mask; \
649 plgpio->csave_regs[i].__reg = \
650 _tmp | (plgpio->csave_regs[i].__reg & _mask); \
653 static int plgpio_resume(struct device *dev)
655 struct plgpio *plgpio = dev_get_drvdata(dev);
656 int i, reg_count = DIV_ROUND_UP(plgpio->chip.ngpio, MAX_GPIO_PER_REG);
657 void __iomem *off;
658 u32 mask, tmp;
660 for (i = 0; i < reg_count; i++) {
661 off = plgpio->base + i * sizeof(int *);
663 if (i == reg_count - 1) {
664 mask = (1 << (plgpio->chip.ngpio - i *
665 MAX_GPIO_PER_REG)) - 1;
667 if (plgpio->regs.enb != -1)
668 plgpio_prepare_reg(enb, off, mask, tmp);
670 if (plgpio->regs.eit != -1)
671 plgpio_prepare_reg(eit, off, mask, tmp);
673 plgpio_prepare_reg(wdata, off, mask, tmp);
674 plgpio_prepare_reg(dir, off, mask, tmp);
675 plgpio_prepare_reg(ie, off, mask, tmp);
678 writel_relaxed(plgpio->csave_regs[i].wdata, plgpio->regs.wdata +
679 off);
680 writel_relaxed(plgpio->csave_regs[i].dir, plgpio->regs.dir +
681 off);
683 if (plgpio->regs.eit != -1)
684 writel_relaxed(plgpio->csave_regs[i].eit,
685 plgpio->regs.eit + off);
687 writel_relaxed(plgpio->csave_regs[i].ie, plgpio->regs.ie + off);
689 if (plgpio->regs.enb != -1)
690 writel_relaxed(plgpio->csave_regs[i].enb,
691 plgpio->regs.enb + off);
694 return 0;
696 #endif
698 static SIMPLE_DEV_PM_OPS(plgpio_dev_pm_ops, plgpio_suspend, plgpio_resume);
700 static const struct of_device_id plgpio_of_match[] = {
701 { .compatible = "st,spear-plgpio" },
705 static struct platform_driver plgpio_driver = {
706 .probe = plgpio_probe,
707 .driver = {
708 .name = "spear-plgpio",
709 .pm = &plgpio_dev_pm_ops,
710 .of_match_table = plgpio_of_match,
714 static int __init plgpio_init(void)
716 return platform_driver_register(&plgpio_driver);
718 subsys_initcall(plgpio_init);