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Viresh Kumar604bb7d2012-10-27 15:21:37 +05301/*
2 * SPEAr platform PLGPIO driver
3 *
4 * Copyright (C) 2012 ST Microelectronics
5 * Viresh Kumar <viresh.kumar@linaro.org>
6 *
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.
10 */
11
12#include <linux/clk.h>
13#include <linux/err.h>
14#include <linux/gpio.h>
15#include <linux/io.h>
16#include <linux/irq.h>
17#include <linux/irqdomain.h>
18#include <linux/module.h>
19#include <linux/pinctrl/consumer.h>
20#include <linux/platform_device.h>
21#include <linux/pm.h>
22#include <linux/spinlock.h>
23#include <asm/mach/irq.h>
24
25#define MAX_GPIO_PER_REG 32
26#define PIN_OFFSET(pin) (pin % MAX_GPIO_PER_REG)
27#define REG_OFFSET(base, reg, pin) (base + reg + (pin / MAX_GPIO_PER_REG) \
28 * sizeof(int *))
29
30/*
31 * plgpio pins in all machines are not one to one mapped, bitwise with registers
32 * bits. These set of macros define register masks for which below functions
33 * (pin_to_offset and offset_to_pin) are required to be called.
34 */
35#define PTO_ENB_REG 0x001
36#define PTO_WDATA_REG 0x002
37#define PTO_DIR_REG 0x004
38#define PTO_IE_REG 0x008
39#define PTO_RDATA_REG 0x010
40#define PTO_MIS_REG 0x020
41
42struct plgpio_regs {
43 u32 enb; /* enable register */
44 u32 wdata; /* write data register */
45 u32 dir; /* direction set register */
46 u32 rdata; /* read data register */
47 u32 ie; /* interrupt enable register */
48 u32 mis; /* mask interrupt status register */
49 u32 eit; /* edge interrupt type */
50};
51
52/*
53 * struct plgpio: plgpio driver specific structure
54 *
55 * lock: lock for guarding gpio registers
56 * base: base address of plgpio block
57 * irq_base: irq number of plgpio0
58 * chip: gpio framework specific chip information structure
59 * p2o: function ptr for pin to offset conversion. This is required only for
60 * machines where mapping b/w pin and offset is not 1-to-1.
61 * o2p: function ptr for offset to pin conversion. This is required only for
62 * machines where mapping b/w pin and offset is not 1-to-1.
63 * p2o_regs: mask of registers for which p2o and o2p are applicable
64 * regs: register offsets
65 * csave_regs: context save registers for standby/sleep/hibernate cases
66 */
67struct plgpio {
68 spinlock_t lock;
69 void __iomem *base;
70 struct clk *clk;
71 unsigned irq_base;
72 struct irq_domain *irq_domain;
73 struct gpio_chip chip;
74 int (*p2o)(int pin); /* pin_to_offset */
75 int (*o2p)(int offset); /* offset_to_pin */
76 u32 p2o_regs;
77 struct plgpio_regs regs;
78#ifdef CONFIG_PM
79 struct plgpio_regs *csave_regs;
80#endif
81};
82
83/* register manipulation inline functions */
84static inline u32 is_plgpio_set(void __iomem *base, u32 pin, u32 reg)
85{
86 u32 offset = PIN_OFFSET(pin);
87 void __iomem *reg_off = REG_OFFSET(base, reg, pin);
88 u32 val = readl_relaxed(reg_off);
89
90 return !!(val & (1 << offset));
91}
92
93static inline void plgpio_reg_set(void __iomem *base, u32 pin, u32 reg)
94{
95 u32 offset = PIN_OFFSET(pin);
96 void __iomem *reg_off = REG_OFFSET(base, reg, pin);
97 u32 val = readl_relaxed(reg_off);
98
99 writel_relaxed(val | (1 << offset), reg_off);
100}
101
102static inline void plgpio_reg_reset(void __iomem *base, u32 pin, u32 reg)
103{
104 u32 offset = PIN_OFFSET(pin);
105 void __iomem *reg_off = REG_OFFSET(base, reg, pin);
106 u32 val = readl_relaxed(reg_off);
107
108 writel_relaxed(val & ~(1 << offset), reg_off);
109}
110
111/* gpio framework specific routines */
112static int plgpio_direction_input(struct gpio_chip *chip, unsigned offset)
113{
114 struct plgpio *plgpio = container_of(chip, struct plgpio, chip);
115 unsigned long flags;
116
117 /* get correct offset for "offset" pin */
118 if (plgpio->p2o && (plgpio->p2o_regs & PTO_DIR_REG)) {
119 offset = plgpio->p2o(offset);
120 if (offset == -1)
121 return -EINVAL;
122 }
123
124 spin_lock_irqsave(&plgpio->lock, flags);
125 plgpio_reg_set(plgpio->base, offset, plgpio->regs.dir);
126 spin_unlock_irqrestore(&plgpio->lock, flags);
127
128 return 0;
129}
130
131static int plgpio_direction_output(struct gpio_chip *chip, unsigned offset,
132 int value)
133{
134 struct plgpio *plgpio = container_of(chip, struct plgpio, chip);
135 unsigned long flags;
136 unsigned dir_offset = offset, wdata_offset = offset, tmp;
137
138 /* get correct offset for "offset" pin */
139 if (plgpio->p2o && (plgpio->p2o_regs & (PTO_DIR_REG | PTO_WDATA_REG))) {
140 tmp = plgpio->p2o(offset);
141 if (tmp == -1)
142 return -EINVAL;
143
144 if (plgpio->p2o_regs & PTO_DIR_REG)
145 dir_offset = tmp;
146 if (plgpio->p2o_regs & PTO_WDATA_REG)
147 wdata_offset = tmp;
148 }
149
150 spin_lock_irqsave(&plgpio->lock, flags);
151 if (value)
152 plgpio_reg_set(plgpio->base, wdata_offset,
153 plgpio->regs.wdata);
154 else
155 plgpio_reg_reset(plgpio->base, wdata_offset,
156 plgpio->regs.wdata);
157
158 plgpio_reg_reset(plgpio->base, dir_offset, plgpio->regs.dir);
159 spin_unlock_irqrestore(&plgpio->lock, flags);
160
161 return 0;
162}
163
164static int plgpio_get_value(struct gpio_chip *chip, unsigned offset)
165{
166 struct plgpio *plgpio = container_of(chip, struct plgpio, chip);
167
168 if (offset >= chip->ngpio)
169 return -EINVAL;
170
171 /* get correct offset for "offset" pin */
172 if (plgpio->p2o && (plgpio->p2o_regs & PTO_RDATA_REG)) {
173 offset = plgpio->p2o(offset);
174 if (offset == -1)
175 return -EINVAL;
176 }
177
178 return is_plgpio_set(plgpio->base, offset, plgpio->regs.rdata);
179}
180
181static void plgpio_set_value(struct gpio_chip *chip, unsigned offset, int value)
182{
183 struct plgpio *plgpio = container_of(chip, struct plgpio, chip);
184
185 if (offset >= chip->ngpio)
186 return;
187
188 /* get correct offset for "offset" pin */
189 if (plgpio->p2o && (plgpio->p2o_regs & PTO_WDATA_REG)) {
190 offset = plgpio->p2o(offset);
191 if (offset == -1)
192 return;
193 }
194
195 if (value)
196 plgpio_reg_set(plgpio->base, offset, plgpio->regs.wdata);
197 else
198 plgpio_reg_reset(plgpio->base, offset, plgpio->regs.wdata);
199}
200
201static int plgpio_request(struct gpio_chip *chip, unsigned offset)
202{
203 struct plgpio *plgpio = container_of(chip, struct plgpio, chip);
204 int gpio = chip->base + offset;
205 unsigned long flags;
206 int ret = 0;
207
208 if (offset >= chip->ngpio)
209 return -EINVAL;
210
211 ret = pinctrl_request_gpio(gpio);
212 if (ret)
213 return ret;
214
215 if (!IS_ERR(plgpio->clk)) {
Viresh Kumarf92bc452012-11-14 14:44:07 +0530216 ret = clk_enable(plgpio->clk);
Viresh Kumar604bb7d2012-10-27 15:21:37 +0530217 if (ret)
218 goto err0;
219 }
220
221 if (plgpio->regs.enb == -1)
222 return 0;
223
224 /*
225 * put gpio in IN mode before enabling it. This make enabling gpio safe
226 */
227 ret = plgpio_direction_input(chip, offset);
228 if (ret)
229 goto err1;
230
231 /* get correct offset for "offset" pin */
232 if (plgpio->p2o && (plgpio->p2o_regs & PTO_ENB_REG)) {
233 offset = plgpio->p2o(offset);
234 if (offset == -1) {
235 ret = -EINVAL;
236 goto err1;
237 }
238 }
239
240 spin_lock_irqsave(&plgpio->lock, flags);
241 plgpio_reg_set(plgpio->base, offset, plgpio->regs.enb);
242 spin_unlock_irqrestore(&plgpio->lock, flags);
243 return 0;
244
245err1:
Axel Lin98040492012-11-14 16:37:45 +0800246 if (!IS_ERR(plgpio->clk))
Viresh Kumarf92bc452012-11-14 14:44:07 +0530247 clk_disable(plgpio->clk);
Viresh Kumar604bb7d2012-10-27 15:21:37 +0530248err0:
249 pinctrl_free_gpio(gpio);
250 return ret;
251}
252
253static void plgpio_free(struct gpio_chip *chip, unsigned offset)
254{
255 struct plgpio *plgpio = container_of(chip, struct plgpio, chip);
256 int gpio = chip->base + offset;
257 unsigned long flags;
258
259 if (offset >= chip->ngpio)
260 return;
261
262 if (plgpio->regs.enb == -1)
263 goto disable_clk;
264
265 /* get correct offset for "offset" pin */
266 if (plgpio->p2o && (plgpio->p2o_regs & PTO_ENB_REG)) {
267 offset = plgpio->p2o(offset);
268 if (offset == -1)
269 return;
270 }
271
272 spin_lock_irqsave(&plgpio->lock, flags);
273 plgpio_reg_reset(plgpio->base, offset, plgpio->regs.enb);
274 spin_unlock_irqrestore(&plgpio->lock, flags);
275
276disable_clk:
277 if (!IS_ERR(plgpio->clk))
Viresh Kumarf92bc452012-11-14 14:44:07 +0530278 clk_disable(plgpio->clk);
Viresh Kumar604bb7d2012-10-27 15:21:37 +0530279
280 pinctrl_free_gpio(gpio);
281}
282
283static int plgpio_to_irq(struct gpio_chip *chip, unsigned offset)
284{
285 struct plgpio *plgpio = container_of(chip, struct plgpio, chip);
286
Tushar Behera7d8dd202012-11-16 12:20:39 +0530287 if (IS_ERR_VALUE(plgpio->irq_base))
Viresh Kumar604bb7d2012-10-27 15:21:37 +0530288 return -EINVAL;
289
290 return irq_find_mapping(plgpio->irq_domain, offset);
291}
292
293/* PLGPIO IRQ */
294static void plgpio_irq_disable(struct irq_data *d)
295{
296 struct plgpio *plgpio = irq_data_get_irq_chip_data(d);
297 int offset = d->irq - plgpio->irq_base;
298 unsigned long flags;
299
300 /* get correct offset for "offset" pin */
301 if (plgpio->p2o && (plgpio->p2o_regs & PTO_IE_REG)) {
302 offset = plgpio->p2o(offset);
303 if (offset == -1)
304 return;
305 }
306
307 spin_lock_irqsave(&plgpio->lock, flags);
308 plgpio_reg_set(plgpio->base, offset, plgpio->regs.ie);
309 spin_unlock_irqrestore(&plgpio->lock, flags);
310}
311
312static void plgpio_irq_enable(struct irq_data *d)
313{
314 struct plgpio *plgpio = irq_data_get_irq_chip_data(d);
315 int offset = d->irq - plgpio->irq_base;
316 unsigned long flags;
317
318 /* get correct offset for "offset" pin */
319 if (plgpio->p2o && (plgpio->p2o_regs & PTO_IE_REG)) {
320 offset = plgpio->p2o(offset);
321 if (offset == -1)
322 return;
323 }
324
325 spin_lock_irqsave(&plgpio->lock, flags);
326 plgpio_reg_reset(plgpio->base, offset, plgpio->regs.ie);
327 spin_unlock_irqrestore(&plgpio->lock, flags);
328}
329
330static int plgpio_irq_set_type(struct irq_data *d, unsigned trigger)
331{
332 struct plgpio *plgpio = irq_data_get_irq_chip_data(d);
333 int offset = d->irq - plgpio->irq_base;
334 void __iomem *reg_off;
335 unsigned int supported_type = 0, val;
336
337 if (offset >= plgpio->chip.ngpio)
338 return -EINVAL;
339
340 if (plgpio->regs.eit == -1)
341 supported_type = IRQ_TYPE_LEVEL_HIGH;
342 else
343 supported_type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
344
345 if (!(trigger & supported_type))
346 return -EINVAL;
347
348 if (plgpio->regs.eit == -1)
349 return 0;
350
351 reg_off = REG_OFFSET(plgpio->base, plgpio->regs.eit, offset);
352 val = readl_relaxed(reg_off);
353
354 offset = PIN_OFFSET(offset);
355 if (trigger & IRQ_TYPE_EDGE_RISING)
356 writel_relaxed(val | (1 << offset), reg_off);
357 else
358 writel_relaxed(val & ~(1 << offset), reg_off);
359
360 return 0;
361}
362
363static struct irq_chip plgpio_irqchip = {
364 .name = "PLGPIO",
365 .irq_enable = plgpio_irq_enable,
366 .irq_disable = plgpio_irq_disable,
367 .irq_set_type = plgpio_irq_set_type,
368};
369
370static void plgpio_irq_handler(unsigned irq, struct irq_desc *desc)
371{
372 struct plgpio *plgpio = irq_get_handler_data(irq);
373 struct irq_chip *irqchip = irq_desc_get_chip(desc);
374 int regs_count, count, pin, offset, i = 0;
375 unsigned long pending;
376
377 count = plgpio->chip.ngpio;
378 regs_count = DIV_ROUND_UP(count, MAX_GPIO_PER_REG);
379
380 chained_irq_enter(irqchip, desc);
381 /* check all plgpio MIS registers for a possible interrupt */
382 for (; i < regs_count; i++) {
383 pending = readl_relaxed(plgpio->base + plgpio->regs.mis +
384 i * sizeof(int *));
385 if (!pending)
386 continue;
387
388 /* clear interrupts */
389 writel_relaxed(~pending, plgpio->base + plgpio->regs.mis +
390 i * sizeof(int *));
391 /*
392 * clear extra bits in last register having gpios < MAX/REG
393 * ex: Suppose there are max 102 plgpios. then last register
394 * must have only (102 - MAX_GPIO_PER_REG * 3) = 6 relevant bits
395 * so, we must not take other 28 bits into consideration for
396 * checking interrupt. so clear those bits.
397 */
398 count = count - i * MAX_GPIO_PER_REG;
399 if (count < MAX_GPIO_PER_REG)
400 pending &= (1 << count) - 1;
401
402 for_each_set_bit(offset, &pending, MAX_GPIO_PER_REG) {
403 /* get correct pin for "offset" */
404 if (plgpio->o2p && (plgpio->p2o_regs & PTO_MIS_REG)) {
405 pin = plgpio->o2p(offset);
406 if (pin == -1)
407 continue;
408 } else
409 pin = offset;
410
411 /* get correct irq line number */
412 pin = i * MAX_GPIO_PER_REG + pin;
413 generic_handle_irq(plgpio_to_irq(&plgpio->chip, pin));
414 }
415 }
416 chained_irq_exit(irqchip, desc);
417}
418
419/*
420 * pin to offset and offset to pin converter functions
421 *
422 * In spear310 there is inconsistency among bit positions in plgpio regiseters,
423 * for different plgpio pins. For example: for pin 27, bit offset is 23, pin
424 * 28-33 are not supported, pin 95 has offset bit 95, bit 100 has offset bit 1
425 */
426static int spear310_p2o(int pin)
427{
428 int offset = pin;
429
430 if (pin <= 27)
431 offset += 4;
432 else if (pin <= 33)
433 offset = -1;
434 else if (pin <= 97)
435 offset -= 2;
436 else if (pin <= 101)
437 offset = 101 - pin;
438 else
439 offset = -1;
440
441 return offset;
442}
443
444int spear310_o2p(int offset)
445{
446 if (offset <= 3)
447 return 101 - offset;
448 else if (offset <= 31)
449 return offset - 4;
450 else
451 return offset + 2;
452}
453
454static int __devinit plgpio_probe_dt(struct platform_device *pdev,
455 struct plgpio *plgpio)
456{
457 struct device_node *np = pdev->dev.of_node;
458 int ret = -EINVAL;
459 u32 val;
460
461 if (of_machine_is_compatible("st,spear310")) {
462 plgpio->p2o = spear310_p2o;
463 plgpio->o2p = spear310_o2p;
464 plgpio->p2o_regs = PTO_WDATA_REG | PTO_DIR_REG | PTO_IE_REG |
465 PTO_RDATA_REG | PTO_MIS_REG;
466 }
467
468 if (!of_property_read_u32(np, "st-plgpio,ngpio", &val)) {
469 plgpio->chip.ngpio = val;
470 } else {
471 dev_err(&pdev->dev, "DT: Invalid ngpio field\n");
472 goto end;
473 }
474
475 if (!of_property_read_u32(np, "st-plgpio,enb-reg", &val))
476 plgpio->regs.enb = val;
477 else
478 plgpio->regs.enb = -1;
479
480 if (!of_property_read_u32(np, "st-plgpio,wdata-reg", &val)) {
481 plgpio->regs.wdata = val;
482 } else {
483 dev_err(&pdev->dev, "DT: Invalid wdata reg\n");
484 goto end;
485 }
486
487 if (!of_property_read_u32(np, "st-plgpio,dir-reg", &val)) {
488 plgpio->regs.dir = val;
489 } else {
490 dev_err(&pdev->dev, "DT: Invalid dir reg\n");
491 goto end;
492 }
493
494 if (!of_property_read_u32(np, "st-plgpio,ie-reg", &val)) {
495 plgpio->regs.ie = val;
496 } else {
497 dev_err(&pdev->dev, "DT: Invalid ie reg\n");
498 goto end;
499 }
500
501 if (!of_property_read_u32(np, "st-plgpio,rdata-reg", &val)) {
502 plgpio->regs.rdata = val;
503 } else {
504 dev_err(&pdev->dev, "DT: Invalid rdata reg\n");
505 goto end;
506 }
507
508 if (!of_property_read_u32(np, "st-plgpio,mis-reg", &val)) {
509 plgpio->regs.mis = val;
510 } else {
511 dev_err(&pdev->dev, "DT: Invalid mis reg\n");
512 goto end;
513 }
514
515 if (!of_property_read_u32(np, "st-plgpio,eit-reg", &val))
516 plgpio->regs.eit = val;
517 else
518 plgpio->regs.eit = -1;
519
520 return 0;
521
522end:
523 return ret;
524}
525static int __devinit plgpio_probe(struct platform_device *pdev)
526{
527 struct device_node *np = pdev->dev.of_node;
528 struct plgpio *plgpio;
529 struct resource *res;
530 int ret, irq, i;
531
532 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
533 if (!res) {
534 dev_err(&pdev->dev, "invalid IORESOURCE_MEM\n");
535 return -EBUSY;
536 }
537
538 plgpio = devm_kzalloc(&pdev->dev, sizeof(*plgpio), GFP_KERNEL);
539 if (!plgpio) {
540 dev_err(&pdev->dev, "memory allocation fail\n");
541 return -ENOMEM;
542 }
543
544 plgpio->base = devm_request_and_ioremap(&pdev->dev, res);
545 if (!plgpio->base) {
546 dev_err(&pdev->dev, "request and ioremap fail\n");
547 return -ENOMEM;
548 }
549
550 ret = plgpio_probe_dt(pdev, plgpio);
551 if (ret) {
552 dev_err(&pdev->dev, "DT probe failed\n");
553 return ret;
554 }
555
556 plgpio->clk = devm_clk_get(&pdev->dev, NULL);
557 if (IS_ERR(plgpio->clk))
558 dev_warn(&pdev->dev, "clk_get() failed, work without it\n");
559
560#ifdef CONFIG_PM
561 plgpio->csave_regs = devm_kzalloc(&pdev->dev,
562 sizeof(*plgpio->csave_regs) *
563 DIV_ROUND_UP(plgpio->chip.ngpio, MAX_GPIO_PER_REG),
564 GFP_KERNEL);
565 if (!plgpio->csave_regs) {
566 dev_err(&pdev->dev, "csave registers memory allocation fail\n");
567 return -ENOMEM;
568 }
569#endif
570
571 platform_set_drvdata(pdev, plgpio);
572 spin_lock_init(&plgpio->lock);
573
574 plgpio->irq_base = -1;
575 plgpio->chip.base = -1;
576 plgpio->chip.request = plgpio_request;
577 plgpio->chip.free = plgpio_free;
578 plgpio->chip.direction_input = plgpio_direction_input;
579 plgpio->chip.direction_output = plgpio_direction_output;
580 plgpio->chip.get = plgpio_get_value;
581 plgpio->chip.set = plgpio_set_value;
582 plgpio->chip.to_irq = plgpio_to_irq;
583 plgpio->chip.label = dev_name(&pdev->dev);
584 plgpio->chip.dev = &pdev->dev;
585 plgpio->chip.owner = THIS_MODULE;
586
Viresh Kumarf92bc452012-11-14 14:44:07 +0530587 if (!IS_ERR(plgpio->clk)) {
588 ret = clk_prepare(plgpio->clk);
589 if (ret) {
590 dev_err(&pdev->dev, "clk prepare failed\n");
591 return ret;
592 }
593 }
594
Viresh Kumar604bb7d2012-10-27 15:21:37 +0530595 ret = gpiochip_add(&plgpio->chip);
596 if (ret) {
597 dev_err(&pdev->dev, "unable to add gpio chip\n");
Viresh Kumarf92bc452012-11-14 14:44:07 +0530598 goto unprepare_clk;
Viresh Kumar604bb7d2012-10-27 15:21:37 +0530599 }
600
601 irq = platform_get_irq(pdev, 0);
602 if (irq < 0) {
603 dev_info(&pdev->dev, "irqs not supported\n");
604 return 0;
605 }
606
607 plgpio->irq_base = irq_alloc_descs(-1, 0, plgpio->chip.ngpio, 0);
608 if (IS_ERR_VALUE(plgpio->irq_base)) {
609 /* we would not support irq for gpio */
610 dev_warn(&pdev->dev, "couldn't allocate irq base\n");
611 return 0;
612 }
613
614 plgpio->irq_domain = irq_domain_add_legacy(np, plgpio->chip.ngpio,
615 plgpio->irq_base, 0, &irq_domain_simple_ops, NULL);
616 if (WARN_ON(!plgpio->irq_domain)) {
617 dev_err(&pdev->dev, "irq domain init failed\n");
618 irq_free_descs(plgpio->irq_base, plgpio->chip.ngpio);
619 ret = -ENXIO;
620 goto remove_gpiochip;
621 }
622
623 irq_set_chained_handler(irq, plgpio_irq_handler);
624 for (i = 0; i < plgpio->chip.ngpio; i++) {
625 irq_set_chip_and_handler(i + plgpio->irq_base, &plgpio_irqchip,
626 handle_simple_irq);
627 set_irq_flags(i + plgpio->irq_base, IRQF_VALID);
628 irq_set_chip_data(i + plgpio->irq_base, plgpio);
629 }
630
631 irq_set_handler_data(irq, plgpio);
632 dev_info(&pdev->dev, "PLGPIO registered with IRQs\n");
633
634 return 0;
635
636remove_gpiochip:
637 dev_info(&pdev->dev, "Remove gpiochip\n");
638 if (gpiochip_remove(&plgpio->chip))
639 dev_err(&pdev->dev, "unable to remove gpiochip\n");
Viresh Kumarf92bc452012-11-14 14:44:07 +0530640unprepare_clk:
641 if (!IS_ERR(plgpio->clk))
642 clk_unprepare(plgpio->clk);
Viresh Kumar604bb7d2012-10-27 15:21:37 +0530643
644 return ret;
645}
646
647#ifdef CONFIG_PM
648static int plgpio_suspend(struct device *dev)
649{
650 struct plgpio *plgpio = dev_get_drvdata(dev);
651 int i, reg_count = DIV_ROUND_UP(plgpio->chip.ngpio, MAX_GPIO_PER_REG);
652 void __iomem *off;
653
654 for (i = 0; i < reg_count; i++) {
655 off = plgpio->base + i * sizeof(int *);
656
657 if (plgpio->regs.enb != -1)
658 plgpio->csave_regs[i].enb =
659 readl_relaxed(plgpio->regs.enb + off);
660 if (plgpio->regs.eit != -1)
661 plgpio->csave_regs[i].eit =
662 readl_relaxed(plgpio->regs.eit + off);
663 plgpio->csave_regs[i].wdata = readl_relaxed(plgpio->regs.wdata +
664 off);
665 plgpio->csave_regs[i].dir = readl_relaxed(plgpio->regs.dir +
666 off);
667 plgpio->csave_regs[i].ie = readl_relaxed(plgpio->regs.ie + off);
668 }
669
670 return 0;
671}
672
673/*
674 * This is used to correct the values in end registers. End registers contain
675 * extra bits that might be used for other purpose in platform. So, we shouldn't
676 * overwrite these bits. This macro, reads given register again, preserves other
677 * bit values (non-plgpio bits), and retain captured value (plgpio bits).
678 */
679#define plgpio_prepare_reg(__reg, _off, _mask, _tmp) \
680{ \
681 _tmp = readl_relaxed(plgpio->regs.__reg + _off); \
682 _tmp &= ~_mask; \
683 plgpio->csave_regs[i].__reg = \
684 _tmp | (plgpio->csave_regs[i].__reg & _mask); \
685}
686
687static int plgpio_resume(struct device *dev)
688{
689 struct plgpio *plgpio = dev_get_drvdata(dev);
690 int i, reg_count = DIV_ROUND_UP(plgpio->chip.ngpio, MAX_GPIO_PER_REG);
691 void __iomem *off;
692 u32 mask, tmp;
693
694 for (i = 0; i < reg_count; i++) {
695 off = plgpio->base + i * sizeof(int *);
696
697 if (i == reg_count - 1) {
698 mask = (1 << (plgpio->chip.ngpio - i *
699 MAX_GPIO_PER_REG)) - 1;
700
701 if (plgpio->regs.enb != -1)
702 plgpio_prepare_reg(enb, off, mask, tmp);
703
704 if (plgpio->regs.eit != -1)
705 plgpio_prepare_reg(eit, off, mask, tmp);
706
707 plgpio_prepare_reg(wdata, off, mask, tmp);
708 plgpio_prepare_reg(dir, off, mask, tmp);
709 plgpio_prepare_reg(ie, off, mask, tmp);
710 }
711
712 writel_relaxed(plgpio->csave_regs[i].wdata, plgpio->regs.wdata +
713 off);
714 writel_relaxed(plgpio->csave_regs[i].dir, plgpio->regs.dir +
715 off);
716
717 if (plgpio->regs.eit != -1)
718 writel_relaxed(plgpio->csave_regs[i].eit,
719 plgpio->regs.eit + off);
720
721 writel_relaxed(plgpio->csave_regs[i].ie, plgpio->regs.ie + off);
722
723 if (plgpio->regs.enb != -1)
724 writel_relaxed(plgpio->csave_regs[i].enb,
725 plgpio->regs.enb + off);
726 }
727
728 return 0;
729}
730#endif
731
732static SIMPLE_DEV_PM_OPS(plgpio_dev_pm_ops, plgpio_suspend, plgpio_resume);
733
734static const struct of_device_id plgpio_of_match[] = {
735 { .compatible = "st,spear-plgpio" },
736 {}
737};
738MODULE_DEVICE_TABLE(of, plgpio_of_match);
739
740static struct platform_driver plgpio_driver = {
741 .probe = plgpio_probe,
742 .driver = {
743 .owner = THIS_MODULE,
744 .name = "spear-plgpio",
745 .pm = &plgpio_dev_pm_ops,
746 .of_match_table = of_match_ptr(plgpio_of_match),
747 },
748};
749
750static int __init plgpio_init(void)
751{
752 return platform_driver_register(&plgpio_driver);
753}
754subsys_initcall(plgpio_init);
755
756MODULE_AUTHOR("Viresh Kumar <viresh.kumar@linaro.org>");
757MODULE_DESCRIPTION("ST Microlectronics SPEAr PLGPIO driver");
758MODULE_LICENSE("GPL");