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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Xilinx gpio driver for xps/axi_gpio IP.
4 *
5 * Copyright 2008 - 2013 Xilinx, Inc.
6 */
7
8#include <linux/bitmap.h>
9#include <linux/bitops.h>
10#include <linux/clk.h>
11#include <linux/errno.h>
12#include <linux/gpio/driver.h>
13#include <linux/init.h>
14#include <linux/interrupt.h>
15#include <linux/io.h>
16#include <linux/irq.h>
17#include <linux/module.h>
18#include <linux/of.h>
19#include <linux/platform_device.h>
20#include <linux/pm_runtime.h>
21#include <linux/slab.h>
22
23/* Register Offset Definitions */
24#define XGPIO_DATA_OFFSET (0x0) /* Data register */
25#define XGPIO_TRI_OFFSET (0x4) /* I/O direction register */
26
27#define XGPIO_CHANNEL0_OFFSET 0x0
28#define XGPIO_CHANNEL1_OFFSET 0x8
29
30#define XGPIO_GIER_OFFSET 0x11c /* Global Interrupt Enable */
31#define XGPIO_GIER_IE BIT(31)
32#define XGPIO_IPISR_OFFSET 0x120 /* IP Interrupt Status */
33#define XGPIO_IPIER_OFFSET 0x128 /* IP Interrupt Enable */
34
35/* Read/Write access to the GPIO registers */
36#if defined(CONFIG_ARCH_ZYNQ) || defined(CONFIG_X86)
37# define xgpio_readreg(offset) readl(offset)
38# define xgpio_writereg(offset, val) writel(val, offset)
39#else
40# define xgpio_readreg(offset) __raw_readl(offset)
41# define xgpio_writereg(offset, val) __raw_writel(val, offset)
42#endif
43
44/**
45 * struct xgpio_instance - Stores information about GPIO device
46 * @gc: GPIO chip
47 * @regs: register block
48 * @hw_map: GPIO pin mapping on hardware side
49 * @sw_map: GPIO pin mapping on software side
50 * @state: GPIO write state shadow register
51 * @last_irq_read: GPIO read state register from last interrupt
52 * @dir: GPIO direction shadow register
53 * @gpio_lock: Lock used for synchronization
54 * @irq: IRQ used by GPIO device
55 * @enable: GPIO IRQ enable/disable bitfield
56 * @rising_edge: GPIO IRQ rising edge enable/disable bitfield
57 * @falling_edge: GPIO IRQ falling edge enable/disable bitfield
58 * @clk: clock resource for this driver
59 */
60struct xgpio_instance {
61 struct gpio_chip gc;
62 void __iomem *regs;
63 DECLARE_BITMAP(hw_map, 64);
64 DECLARE_BITMAP(sw_map, 64);
65 DECLARE_BITMAP(state, 64);
66 DECLARE_BITMAP(last_irq_read, 64);
67 DECLARE_BITMAP(dir, 64);
68 spinlock_t gpio_lock; /* For serializing operations */
69 int irq;
70 DECLARE_BITMAP(enable, 64);
71 DECLARE_BITMAP(rising_edge, 64);
72 DECLARE_BITMAP(falling_edge, 64);
73 struct clk *clk;
74};
75
76static inline int xgpio_from_bit(struct xgpio_instance *chip, int bit)
77{
78 return bitmap_bitremap(bit, chip->hw_map, chip->sw_map, 64);
79}
80
81static inline int xgpio_to_bit(struct xgpio_instance *chip, int gpio)
82{
83 return bitmap_bitremap(gpio, chip->sw_map, chip->hw_map, 64);
84}
85
86static inline u32 xgpio_get_value32(const unsigned long *map, int bit)
87{
88 const size_t index = BIT_WORD(bit);
89 const unsigned long offset = (bit % BITS_PER_LONG) & BIT(5);
90
91 return (map[index] >> offset) & 0xFFFFFFFFul;
92}
93
94static inline void xgpio_set_value32(unsigned long *map, int bit, u32 v)
95{
96 const size_t index = BIT_WORD(bit);
97 const unsigned long offset = (bit % BITS_PER_LONG) & BIT(5);
98
99 map[index] &= ~(0xFFFFFFFFul << offset);
100 map[index] |= (unsigned long)v << offset;
101}
102
103static inline int xgpio_regoffset(struct xgpio_instance *chip, int ch)
104{
105 switch (ch) {
106 case 0:
107 return XGPIO_CHANNEL0_OFFSET;
108 case 1:
109 return XGPIO_CHANNEL1_OFFSET;
110 default:
111 return -EINVAL;
112 }
113}
114
115static void xgpio_read_ch(struct xgpio_instance *chip, int reg, int bit, unsigned long *a)
116{
117 void __iomem *addr = chip->regs + reg + xgpio_regoffset(chip, bit / 32);
118
119 xgpio_set_value32(a, bit, xgpio_readreg(addr));
120}
121
122static void xgpio_write_ch(struct xgpio_instance *chip, int reg, int bit, unsigned long *a)
123{
124 void __iomem *addr = chip->regs + reg + xgpio_regoffset(chip, bit / 32);
125
126 xgpio_writereg(addr, xgpio_get_value32(a, bit));
127}
128
129static void xgpio_read_ch_all(struct xgpio_instance *chip, int reg, unsigned long *a)
130{
131 int bit, lastbit = xgpio_to_bit(chip, chip->gc.ngpio - 1);
132
133 for (bit = 0; bit <= lastbit ; bit += 32)
134 xgpio_read_ch(chip, reg, bit, a);
135}
136
137static void xgpio_write_ch_all(struct xgpio_instance *chip, int reg, unsigned long *a)
138{
139 int bit, lastbit = xgpio_to_bit(chip, chip->gc.ngpio - 1);
140
141 for (bit = 0; bit <= lastbit ; bit += 32)
142 xgpio_write_ch(chip, reg, bit, a);
143}
144
145/**
146 * xgpio_get - Read the specified signal of the GPIO device.
147 * @gc: Pointer to gpio_chip device structure.
148 * @gpio: GPIO signal number.
149 *
150 * This function reads the specified signal of the GPIO device.
151 *
152 * Return:
153 * 0 if direction of GPIO signals is set as input otherwise it
154 * returns negative error value.
155 */
156static int xgpio_get(struct gpio_chip *gc, unsigned int gpio)
157{
158 struct xgpio_instance *chip = gpiochip_get_data(gc);
159 int bit = xgpio_to_bit(chip, gpio);
160 DECLARE_BITMAP(state, 64);
161
162 xgpio_read_ch(chip, XGPIO_DATA_OFFSET, bit, state);
163
164 return test_bit(bit, state);
165}
166
167/**
168 * xgpio_set - Write the specified signal of the GPIO device.
169 * @gc: Pointer to gpio_chip device structure.
170 * @gpio: GPIO signal number.
171 * @val: Value to be written to specified signal.
172 *
173 * This function writes the specified value in to the specified signal of the
174 * GPIO device.
175 */
176static void xgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
177{
178 unsigned long flags;
179 struct xgpio_instance *chip = gpiochip_get_data(gc);
180 int bit = xgpio_to_bit(chip, gpio);
181
182 spin_lock_irqsave(&chip->gpio_lock, flags);
183
184 /* Write to GPIO signal and set its direction to output */
185 __assign_bit(bit, chip->state, val);
186
187 xgpio_write_ch(chip, XGPIO_DATA_OFFSET, bit, chip->state);
188
189 spin_unlock_irqrestore(&chip->gpio_lock, flags);
190}
191
192/**
193 * xgpio_set_multiple - Write the specified signals of the GPIO device.
194 * @gc: Pointer to gpio_chip device structure.
195 * @mask: Mask of the GPIOS to modify.
196 * @bits: Value to be wrote on each GPIO
197 *
198 * This function writes the specified values into the specified signals of the
199 * GPIO devices.
200 */
201static void xgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
202 unsigned long *bits)
203{
204 DECLARE_BITMAP(hw_mask, 64);
205 DECLARE_BITMAP(hw_bits, 64);
206 DECLARE_BITMAP(state, 64);
207 unsigned long flags;
208 struct xgpio_instance *chip = gpiochip_get_data(gc);
209
210 bitmap_remap(hw_mask, mask, chip->sw_map, chip->hw_map, 64);
211 bitmap_remap(hw_bits, bits, chip->sw_map, chip->hw_map, 64);
212
213 spin_lock_irqsave(&chip->gpio_lock, flags);
214
215 bitmap_replace(state, chip->state, hw_bits, hw_mask, 64);
216
217 xgpio_write_ch_all(chip, XGPIO_DATA_OFFSET, state);
218
219 bitmap_copy(chip->state, state, 64);
220
221 spin_unlock_irqrestore(&chip->gpio_lock, flags);
222}
223
224/**
225 * xgpio_dir_in - Set the direction of the specified GPIO signal as input.
226 * @gc: Pointer to gpio_chip device structure.
227 * @gpio: GPIO signal number.
228 *
229 * Return:
230 * 0 - if direction of GPIO signals is set as input
231 * otherwise it returns negative error value.
232 */
233static int xgpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
234{
235 unsigned long flags;
236 struct xgpio_instance *chip = gpiochip_get_data(gc);
237 int bit = xgpio_to_bit(chip, gpio);
238
239 spin_lock_irqsave(&chip->gpio_lock, flags);
240
241 /* Set the GPIO bit in shadow register and set direction as input */
242 __set_bit(bit, chip->dir);
243 xgpio_write_ch(chip, XGPIO_TRI_OFFSET, bit, chip->dir);
244
245 spin_unlock_irqrestore(&chip->gpio_lock, flags);
246
247 return 0;
248}
249
250/**
251 * xgpio_dir_out - Set the direction of the specified GPIO signal as output.
252 * @gc: Pointer to gpio_chip device structure.
253 * @gpio: GPIO signal number.
254 * @val: Value to be written to specified signal.
255 *
256 * This function sets the direction of specified GPIO signal as output.
257 *
258 * Return:
259 * If all GPIO signals of GPIO chip is configured as input then it returns
260 * error otherwise it returns 0.
261 */
262static int xgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
263{
264 unsigned long flags;
265 struct xgpio_instance *chip = gpiochip_get_data(gc);
266 int bit = xgpio_to_bit(chip, gpio);
267
268 spin_lock_irqsave(&chip->gpio_lock, flags);
269
270 /* Write state of GPIO signal */
271 __assign_bit(bit, chip->state, val);
272 xgpio_write_ch(chip, XGPIO_DATA_OFFSET, bit, chip->state);
273
274 /* Clear the GPIO bit in shadow register and set direction as output */
275 __clear_bit(bit, chip->dir);
276 xgpio_write_ch(chip, XGPIO_TRI_OFFSET, bit, chip->dir);
277
278 spin_unlock_irqrestore(&chip->gpio_lock, flags);
279
280 return 0;
281}
282
283/**
284 * xgpio_save_regs - Set initial values of GPIO pins
285 * @chip: Pointer to GPIO instance
286 */
287static void xgpio_save_regs(struct xgpio_instance *chip)
288{
289 xgpio_write_ch_all(chip, XGPIO_DATA_OFFSET, chip->state);
290 xgpio_write_ch_all(chip, XGPIO_TRI_OFFSET, chip->dir);
291}
292
293static int xgpio_request(struct gpio_chip *chip, unsigned int offset)
294{
295 int ret;
296
297 ret = pm_runtime_get_sync(chip->parent);
298 /*
299 * If the device is already active pm_runtime_get() will return 1 on
300 * success, but gpio_request still needs to return 0.
301 */
302 return ret < 0 ? ret : 0;
303}
304
305static void xgpio_free(struct gpio_chip *chip, unsigned int offset)
306{
307 pm_runtime_put(chip->parent);
308}
309
310static int __maybe_unused xgpio_suspend(struct device *dev)
311{
312 struct xgpio_instance *gpio = dev_get_drvdata(dev);
313 struct irq_data *data = irq_get_irq_data(gpio->irq);
314
315 if (!data) {
316 dev_dbg(dev, "IRQ not connected\n");
317 return pm_runtime_force_suspend(dev);
318 }
319
320 if (!irqd_is_wakeup_set(data))
321 return pm_runtime_force_suspend(dev);
322
323 return 0;
324}
325
326/**
327 * xgpio_remove - Remove method for the GPIO device.
328 * @pdev: pointer to the platform device
329 *
330 * This function remove gpiochips and frees all the allocated resources.
331 *
332 * Return: 0 always
333 */
334static void xgpio_remove(struct platform_device *pdev)
335{
336 struct xgpio_instance *gpio = platform_get_drvdata(pdev);
337
338 pm_runtime_get_sync(&pdev->dev);
339 pm_runtime_put_noidle(&pdev->dev);
340 pm_runtime_disable(&pdev->dev);
341 clk_disable_unprepare(gpio->clk);
342}
343
344/**
345 * xgpio_irq_ack - Acknowledge a child GPIO interrupt.
346 * @irq_data: per IRQ and chip data passed down to chip functions
347 * This currently does nothing, but irq_ack is unconditionally called by
348 * handle_edge_irq and therefore must be defined.
349 */
350static void xgpio_irq_ack(struct irq_data *irq_data)
351{
352}
353
354static int __maybe_unused xgpio_resume(struct device *dev)
355{
356 struct xgpio_instance *gpio = dev_get_drvdata(dev);
357 struct irq_data *data = irq_get_irq_data(gpio->irq);
358
359 if (!data) {
360 dev_dbg(dev, "IRQ not connected\n");
361 return pm_runtime_force_resume(dev);
362 }
363
364 if (!irqd_is_wakeup_set(data))
365 return pm_runtime_force_resume(dev);
366
367 return 0;
368}
369
370static int __maybe_unused xgpio_runtime_suspend(struct device *dev)
371{
372 struct xgpio_instance *gpio = dev_get_drvdata(dev);
373
374 clk_disable(gpio->clk);
375
376 return 0;
377}
378
379static int __maybe_unused xgpio_runtime_resume(struct device *dev)
380{
381 struct xgpio_instance *gpio = dev_get_drvdata(dev);
382
383 return clk_enable(gpio->clk);
384}
385
386static const struct dev_pm_ops xgpio_dev_pm_ops = {
387 SET_SYSTEM_SLEEP_PM_OPS(xgpio_suspend, xgpio_resume)
388 SET_RUNTIME_PM_OPS(xgpio_runtime_suspend,
389 xgpio_runtime_resume, NULL)
390};
391
392/**
393 * xgpio_irq_mask - Write the specified signal of the GPIO device.
394 * @irq_data: per IRQ and chip data passed down to chip functions
395 */
396static void xgpio_irq_mask(struct irq_data *irq_data)
397{
398 unsigned long flags;
399 struct xgpio_instance *chip = irq_data_get_irq_chip_data(irq_data);
400 int irq_offset = irqd_to_hwirq(irq_data);
401 int bit = xgpio_to_bit(chip, irq_offset);
402 u32 mask = BIT(bit / 32), temp;
403
404 spin_lock_irqsave(&chip->gpio_lock, flags);
405
406 __clear_bit(bit, chip->enable);
407
408 if (xgpio_get_value32(chip->enable, bit) == 0) {
409 /* Disable per channel interrupt */
410 temp = xgpio_readreg(chip->regs + XGPIO_IPIER_OFFSET);
411 temp &= ~mask;
412 xgpio_writereg(chip->regs + XGPIO_IPIER_OFFSET, temp);
413 }
414 spin_unlock_irqrestore(&chip->gpio_lock, flags);
415
416 gpiochip_disable_irq(&chip->gc, irq_offset);
417}
418
419/**
420 * xgpio_irq_unmask - Write the specified signal of the GPIO device.
421 * @irq_data: per IRQ and chip data passed down to chip functions
422 */
423static void xgpio_irq_unmask(struct irq_data *irq_data)
424{
425 unsigned long flags;
426 struct xgpio_instance *chip = irq_data_get_irq_chip_data(irq_data);
427 int irq_offset = irqd_to_hwirq(irq_data);
428 int bit = xgpio_to_bit(chip, irq_offset);
429 u32 old_enable = xgpio_get_value32(chip->enable, bit);
430 u32 mask = BIT(bit / 32), val;
431
432 gpiochip_enable_irq(&chip->gc, irq_offset);
433
434 spin_lock_irqsave(&chip->gpio_lock, flags);
435
436 __set_bit(bit, chip->enable);
437
438 if (old_enable == 0) {
439 /* Clear any existing per-channel interrupts */
440 val = xgpio_readreg(chip->regs + XGPIO_IPISR_OFFSET);
441 val &= mask;
442 xgpio_writereg(chip->regs + XGPIO_IPISR_OFFSET, val);
443
444 /* Update GPIO IRQ read data before enabling interrupt*/
445 xgpio_read_ch(chip, XGPIO_DATA_OFFSET, bit, chip->last_irq_read);
446
447 /* Enable per channel interrupt */
448 val = xgpio_readreg(chip->regs + XGPIO_IPIER_OFFSET);
449 val |= mask;
450 xgpio_writereg(chip->regs + XGPIO_IPIER_OFFSET, val);
451 }
452
453 spin_unlock_irqrestore(&chip->gpio_lock, flags);
454}
455
456/**
457 * xgpio_set_irq_type - Write the specified signal of the GPIO device.
458 * @irq_data: Per IRQ and chip data passed down to chip functions
459 * @type: Interrupt type that is to be set for the gpio pin
460 *
461 * Return:
462 * 0 if interrupt type is supported otherwise -EINVAL
463 */
464static int xgpio_set_irq_type(struct irq_data *irq_data, unsigned int type)
465{
466 struct xgpio_instance *chip = irq_data_get_irq_chip_data(irq_data);
467 int irq_offset = irqd_to_hwirq(irq_data);
468 int bit = xgpio_to_bit(chip, irq_offset);
469
470 /*
471 * The Xilinx GPIO hardware provides a single interrupt status
472 * indication for any state change in a given GPIO channel (bank).
473 * Therefore, only rising edge or falling edge triggers are
474 * supported.
475 */
476 switch (type & IRQ_TYPE_SENSE_MASK) {
477 case IRQ_TYPE_EDGE_BOTH:
478 __set_bit(bit, chip->rising_edge);
479 __set_bit(bit, chip->falling_edge);
480 break;
481 case IRQ_TYPE_EDGE_RISING:
482 __set_bit(bit, chip->rising_edge);
483 __clear_bit(bit, chip->falling_edge);
484 break;
485 case IRQ_TYPE_EDGE_FALLING:
486 __clear_bit(bit, chip->rising_edge);
487 __set_bit(bit, chip->falling_edge);
488 break;
489 default:
490 return -EINVAL;
491 }
492
493 irq_set_handler_locked(irq_data, handle_edge_irq);
494 return 0;
495}
496
497/**
498 * xgpio_irqhandler - Gpio interrupt service routine
499 * @desc: Pointer to interrupt description
500 */
501static void xgpio_irqhandler(struct irq_desc *desc)
502{
503 struct xgpio_instance *chip = irq_desc_get_handler_data(desc);
504 struct gpio_chip *gc = &chip->gc;
505 struct irq_chip *irqchip = irq_desc_get_chip(desc);
506 DECLARE_BITMAP(rising, 64);
507 DECLARE_BITMAP(falling, 64);
508 DECLARE_BITMAP(all, 64);
509 int irq_offset;
510 u32 status;
511 u32 bit;
512
513 status = xgpio_readreg(chip->regs + XGPIO_IPISR_OFFSET);
514 xgpio_writereg(chip->regs + XGPIO_IPISR_OFFSET, status);
515
516 chained_irq_enter(irqchip, desc);
517
518 spin_lock(&chip->gpio_lock);
519
520 xgpio_read_ch_all(chip, XGPIO_DATA_OFFSET, all);
521
522 bitmap_complement(rising, chip->last_irq_read, 64);
523 bitmap_and(rising, rising, all, 64);
524 bitmap_and(rising, rising, chip->enable, 64);
525 bitmap_and(rising, rising, chip->rising_edge, 64);
526
527 bitmap_complement(falling, all, 64);
528 bitmap_and(falling, falling, chip->last_irq_read, 64);
529 bitmap_and(falling, falling, chip->enable, 64);
530 bitmap_and(falling, falling, chip->falling_edge, 64);
531
532 bitmap_copy(chip->last_irq_read, all, 64);
533 bitmap_or(all, rising, falling, 64);
534
535 spin_unlock(&chip->gpio_lock);
536
537 dev_dbg(gc->parent, "IRQ rising %*pb falling %*pb\n", 64, rising, 64, falling);
538
539 for_each_set_bit(bit, all, 64) {
540 irq_offset = xgpio_from_bit(chip, bit);
541 generic_handle_domain_irq(gc->irq.domain, irq_offset);
542 }
543
544 chained_irq_exit(irqchip, desc);
545}
546
547static const struct irq_chip xgpio_irq_chip = {
548 .name = "gpio-xilinx",
549 .irq_ack = xgpio_irq_ack,
550 .irq_mask = xgpio_irq_mask,
551 .irq_unmask = xgpio_irq_unmask,
552 .irq_set_type = xgpio_set_irq_type,
553 .flags = IRQCHIP_IMMUTABLE,
554 GPIOCHIP_IRQ_RESOURCE_HELPERS,
555};
556
557/**
558 * xgpio_probe - Probe method for the GPIO device.
559 * @pdev: pointer to the platform device
560 *
561 * Return:
562 * It returns 0, if the driver is bound to the GPIO device, or
563 * a negative value if there is an error.
564 */
565static int xgpio_probe(struct platform_device *pdev)
566{
567 struct xgpio_instance *chip;
568 int status = 0;
569 struct device_node *np = pdev->dev.of_node;
570 u32 is_dual = 0;
571 u32 width[2];
572 u32 state[2];
573 u32 dir[2];
574 struct gpio_irq_chip *girq;
575 u32 temp;
576
577 chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
578 if (!chip)
579 return -ENOMEM;
580
581 platform_set_drvdata(pdev, chip);
582
583 /* First, check if the device is dual-channel */
584 of_property_read_u32(np, "xlnx,is-dual", &is_dual);
585
586 /* Setup defaults */
587 memset32(width, 0, ARRAY_SIZE(width));
588 memset32(state, 0, ARRAY_SIZE(state));
589 memset32(dir, 0xFFFFFFFF, ARRAY_SIZE(dir));
590
591 /* Update GPIO state shadow register with default value */
592 of_property_read_u32(np, "xlnx,dout-default", &state[0]);
593 of_property_read_u32(np, "xlnx,dout-default-2", &state[1]);
594
595 bitmap_from_arr32(chip->state, state, 64);
596
597 /* Update GPIO direction shadow register with default value */
598 of_property_read_u32(np, "xlnx,tri-default", &dir[0]);
599 of_property_read_u32(np, "xlnx,tri-default-2", &dir[1]);
600
601 bitmap_from_arr32(chip->dir, dir, 64);
602
603 /*
604 * Check device node and parent device node for device width
605 * and assume default width of 32
606 */
607 if (of_property_read_u32(np, "xlnx,gpio-width", &width[0]))
608 width[0] = 32;
609
610 if (width[0] > 32)
611 return -EINVAL;
612
613 if (is_dual && of_property_read_u32(np, "xlnx,gpio2-width", &width[1]))
614 width[1] = 32;
615
616 if (width[1] > 32)
617 return -EINVAL;
618
619 /* Setup software pin mapping */
620 bitmap_set(chip->sw_map, 0, width[0] + width[1]);
621
622 /* Setup hardware pin mapping */
623 bitmap_set(chip->hw_map, 0, width[0]);
624 bitmap_set(chip->hw_map, 32, width[1]);
625
626 spin_lock_init(&chip->gpio_lock);
627
628 chip->gc.base = -1;
629 chip->gc.ngpio = bitmap_weight(chip->hw_map, 64);
630 chip->gc.parent = &pdev->dev;
631 chip->gc.direction_input = xgpio_dir_in;
632 chip->gc.direction_output = xgpio_dir_out;
633 chip->gc.get = xgpio_get;
634 chip->gc.set = xgpio_set;
635 chip->gc.request = xgpio_request;
636 chip->gc.free = xgpio_free;
637 chip->gc.set_multiple = xgpio_set_multiple;
638
639 chip->gc.label = dev_name(&pdev->dev);
640
641 chip->regs = devm_platform_ioremap_resource(pdev, 0);
642 if (IS_ERR(chip->regs)) {
643 dev_err(&pdev->dev, "failed to ioremap memory resource\n");
644 return PTR_ERR(chip->regs);
645 }
646
647 chip->clk = devm_clk_get_optional(&pdev->dev, NULL);
648 if (IS_ERR(chip->clk))
649 return dev_err_probe(&pdev->dev, PTR_ERR(chip->clk), "input clock not found.\n");
650
651 status = clk_prepare_enable(chip->clk);
652 if (status < 0) {
653 dev_err(&pdev->dev, "Failed to prepare clk\n");
654 return status;
655 }
656 pm_runtime_get_noresume(&pdev->dev);
657 pm_runtime_set_active(&pdev->dev);
658 pm_runtime_enable(&pdev->dev);
659
660 xgpio_save_regs(chip);
661
662 chip->irq = platform_get_irq_optional(pdev, 0);
663 if (chip->irq <= 0)
664 goto skip_irq;
665
666 /* Disable per-channel interrupts */
667 xgpio_writereg(chip->regs + XGPIO_IPIER_OFFSET, 0);
668 /* Clear any existing per-channel interrupts */
669 temp = xgpio_readreg(chip->regs + XGPIO_IPISR_OFFSET);
670 xgpio_writereg(chip->regs + XGPIO_IPISR_OFFSET, temp);
671 /* Enable global interrupts */
672 xgpio_writereg(chip->regs + XGPIO_GIER_OFFSET, XGPIO_GIER_IE);
673
674 girq = &chip->gc.irq;
675 gpio_irq_chip_set_chip(girq, &xgpio_irq_chip);
676 girq->parent_handler = xgpio_irqhandler;
677 girq->num_parents = 1;
678 girq->parents = devm_kcalloc(&pdev->dev, 1,
679 sizeof(*girq->parents),
680 GFP_KERNEL);
681 if (!girq->parents) {
682 status = -ENOMEM;
683 goto err_pm_put;
684 }
685 girq->parents[0] = chip->irq;
686 girq->default_type = IRQ_TYPE_NONE;
687 girq->handler = handle_bad_irq;
688
689skip_irq:
690 status = devm_gpiochip_add_data(&pdev->dev, &chip->gc, chip);
691 if (status) {
692 dev_err(&pdev->dev, "failed to add GPIO chip\n");
693 goto err_pm_put;
694 }
695
696 pm_runtime_put(&pdev->dev);
697 return 0;
698
699err_pm_put:
700 pm_runtime_disable(&pdev->dev);
701 pm_runtime_put_noidle(&pdev->dev);
702 clk_disable_unprepare(chip->clk);
703 return status;
704}
705
706static const struct of_device_id xgpio_of_match[] = {
707 { .compatible = "xlnx,xps-gpio-1.00.a", },
708 { /* end of list */ },
709};
710
711MODULE_DEVICE_TABLE(of, xgpio_of_match);
712
713static struct platform_driver xgpio_plat_driver = {
714 .probe = xgpio_probe,
715 .remove_new = xgpio_remove,
716 .driver = {
717 .name = "gpio-xilinx",
718 .of_match_table = xgpio_of_match,
719 .pm = &xgpio_dev_pm_ops,
720 },
721};
722
723static int __init xgpio_init(void)
724{
725 return platform_driver_register(&xgpio_plat_driver);
726}
727
728subsys_initcall(xgpio_init);
729
730static void __exit xgpio_exit(void)
731{
732 platform_driver_unregister(&xgpio_plat_driver);
733}
734module_exit(xgpio_exit);
735
736MODULE_AUTHOR("Xilinx, Inc.");
737MODULE_DESCRIPTION("Xilinx GPIO driver");
738MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Xilinx gpio driver for xps/axi_gpio IP.
4 *
5 * Copyright 2008 - 2013 Xilinx, Inc.
6 */
7
8#include <linux/bitops.h>
9#include <linux/init.h>
10#include <linux/errno.h>
11#include <linux/module.h>
12#include <linux/of_device.h>
13#include <linux/of_platform.h>
14#include <linux/io.h>
15#include <linux/gpio/driver.h>
16#include <linux/slab.h>
17
18/* Register Offset Definitions */
19#define XGPIO_DATA_OFFSET (0x0) /* Data register */
20#define XGPIO_TRI_OFFSET (0x4) /* I/O direction register */
21
22#define XGPIO_CHANNEL_OFFSET 0x8
23
24/* Read/Write access to the GPIO registers */
25#if defined(CONFIG_ARCH_ZYNQ) || defined(CONFIG_X86)
26# define xgpio_readreg(offset) readl(offset)
27# define xgpio_writereg(offset, val) writel(val, offset)
28#else
29# define xgpio_readreg(offset) __raw_readl(offset)
30# define xgpio_writereg(offset, val) __raw_writel(val, offset)
31#endif
32
33/**
34 * struct xgpio_instance - Stores information about GPIO device
35 * @gc: GPIO chip
36 * @regs: register block
37 * @gpio_width: GPIO width for every channel
38 * @gpio_state: GPIO state shadow register
39 * @gpio_dir: GPIO direction shadow register
40 * @gpio_lock: Lock used for synchronization
41 */
42struct xgpio_instance {
43 struct gpio_chip gc;
44 void __iomem *regs;
45 unsigned int gpio_width[2];
46 u32 gpio_state[2];
47 u32 gpio_dir[2];
48 spinlock_t gpio_lock[2];
49};
50
51static inline int xgpio_index(struct xgpio_instance *chip, int gpio)
52{
53 if (gpio >= chip->gpio_width[0])
54 return 1;
55
56 return 0;
57}
58
59static inline int xgpio_regoffset(struct xgpio_instance *chip, int gpio)
60{
61 if (xgpio_index(chip, gpio))
62 return XGPIO_CHANNEL_OFFSET;
63
64 return 0;
65}
66
67static inline int xgpio_offset(struct xgpio_instance *chip, int gpio)
68{
69 if (xgpio_index(chip, gpio))
70 return gpio - chip->gpio_width[0];
71
72 return gpio;
73}
74
75/**
76 * xgpio_get - Read the specified signal of the GPIO device.
77 * @gc: Pointer to gpio_chip device structure.
78 * @gpio: GPIO signal number.
79 *
80 * This function reads the specified signal of the GPIO device.
81 *
82 * Return:
83 * 0 if direction of GPIO signals is set as input otherwise it
84 * returns negative error value.
85 */
86static int xgpio_get(struct gpio_chip *gc, unsigned int gpio)
87{
88 struct xgpio_instance *chip = gpiochip_get_data(gc);
89 u32 val;
90
91 val = xgpio_readreg(chip->regs + XGPIO_DATA_OFFSET +
92 xgpio_regoffset(chip, gpio));
93
94 return !!(val & BIT(xgpio_offset(chip, gpio)));
95}
96
97/**
98 * xgpio_set - Write the specified signal of the GPIO device.
99 * @gc: Pointer to gpio_chip device structure.
100 * @gpio: GPIO signal number.
101 * @val: Value to be written to specified signal.
102 *
103 * This function writes the specified value in to the specified signal of the
104 * GPIO device.
105 */
106static void xgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
107{
108 unsigned long flags;
109 struct xgpio_instance *chip = gpiochip_get_data(gc);
110 int index = xgpio_index(chip, gpio);
111 int offset = xgpio_offset(chip, gpio);
112
113 spin_lock_irqsave(&chip->gpio_lock[index], flags);
114
115 /* Write to GPIO signal and set its direction to output */
116 if (val)
117 chip->gpio_state[index] |= BIT(offset);
118 else
119 chip->gpio_state[index] &= ~BIT(offset);
120
121 xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
122 xgpio_regoffset(chip, gpio), chip->gpio_state[index]);
123
124 spin_unlock_irqrestore(&chip->gpio_lock[index], flags);
125}
126
127/**
128 * xgpio_set_multiple - Write the specified signals of the GPIO device.
129 * @gc: Pointer to gpio_chip device structure.
130 * @mask: Mask of the GPIOS to modify.
131 * @bits: Value to be wrote on each GPIO
132 *
133 * This function writes the specified values into the specified signals of the
134 * GPIO devices.
135 */
136static void xgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
137 unsigned long *bits)
138{
139 unsigned long flags;
140 struct xgpio_instance *chip = gpiochip_get_data(gc);
141 int index = xgpio_index(chip, 0);
142 int offset, i;
143
144 spin_lock_irqsave(&chip->gpio_lock[index], flags);
145
146 /* Write to GPIO signals */
147 for (i = 0; i < gc->ngpio; i++) {
148 if (*mask == 0)
149 break;
150 /* Once finished with an index write it out to the register */
151 if (index != xgpio_index(chip, i)) {
152 xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
153 index * XGPIO_CHANNEL_OFFSET,
154 chip->gpio_state[index]);
155 spin_unlock_irqrestore(&chip->gpio_lock[index], flags);
156 index = xgpio_index(chip, i);
157 spin_lock_irqsave(&chip->gpio_lock[index], flags);
158 }
159 if (__test_and_clear_bit(i, mask)) {
160 offset = xgpio_offset(chip, i);
161 if (test_bit(i, bits))
162 chip->gpio_state[index] |= BIT(offset);
163 else
164 chip->gpio_state[index] &= ~BIT(offset);
165 }
166 }
167
168 xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
169 index * XGPIO_CHANNEL_OFFSET, chip->gpio_state[index]);
170
171 spin_unlock_irqrestore(&chip->gpio_lock[index], flags);
172}
173
174/**
175 * xgpio_dir_in - Set the direction of the specified GPIO signal as input.
176 * @gc: Pointer to gpio_chip device structure.
177 * @gpio: GPIO signal number.
178 *
179 * Return:
180 * 0 - if direction of GPIO signals is set as input
181 * otherwise it returns negative error value.
182 */
183static int xgpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
184{
185 unsigned long flags;
186 struct xgpio_instance *chip = gpiochip_get_data(gc);
187 int index = xgpio_index(chip, gpio);
188 int offset = xgpio_offset(chip, gpio);
189
190 spin_lock_irqsave(&chip->gpio_lock[index], flags);
191
192 /* Set the GPIO bit in shadow register and set direction as input */
193 chip->gpio_dir[index] |= BIT(offset);
194 xgpio_writereg(chip->regs + XGPIO_TRI_OFFSET +
195 xgpio_regoffset(chip, gpio), chip->gpio_dir[index]);
196
197 spin_unlock_irqrestore(&chip->gpio_lock[index], flags);
198
199 return 0;
200}
201
202/**
203 * xgpio_dir_out - Set the direction of the specified GPIO signal as output.
204 * @gc: Pointer to gpio_chip device structure.
205 * @gpio: GPIO signal number.
206 * @val: Value to be written to specified signal.
207 *
208 * This function sets the direction of specified GPIO signal as output.
209 *
210 * Return:
211 * If all GPIO signals of GPIO chip is configured as input then it returns
212 * error otherwise it returns 0.
213 */
214static int xgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
215{
216 unsigned long flags;
217 struct xgpio_instance *chip = gpiochip_get_data(gc);
218 int index = xgpio_index(chip, gpio);
219 int offset = xgpio_offset(chip, gpio);
220
221 spin_lock_irqsave(&chip->gpio_lock[index], flags);
222
223 /* Write state of GPIO signal */
224 if (val)
225 chip->gpio_state[index] |= BIT(offset);
226 else
227 chip->gpio_state[index] &= ~BIT(offset);
228 xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
229 xgpio_regoffset(chip, gpio), chip->gpio_state[index]);
230
231 /* Clear the GPIO bit in shadow register and set direction as output */
232 chip->gpio_dir[index] &= ~BIT(offset);
233 xgpio_writereg(chip->regs + XGPIO_TRI_OFFSET +
234 xgpio_regoffset(chip, gpio), chip->gpio_dir[index]);
235
236 spin_unlock_irqrestore(&chip->gpio_lock[index], flags);
237
238 return 0;
239}
240
241/**
242 * xgpio_save_regs - Set initial values of GPIO pins
243 * @chip: Pointer to GPIO instance
244 */
245static void xgpio_save_regs(struct xgpio_instance *chip)
246{
247 xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET, chip->gpio_state[0]);
248 xgpio_writereg(chip->regs + XGPIO_TRI_OFFSET, chip->gpio_dir[0]);
249
250 if (!chip->gpio_width[1])
251 return;
252
253 xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET + XGPIO_CHANNEL_OFFSET,
254 chip->gpio_state[1]);
255 xgpio_writereg(chip->regs + XGPIO_TRI_OFFSET + XGPIO_CHANNEL_OFFSET,
256 chip->gpio_dir[1]);
257}
258
259/**
260 * xgpio_of_probe - Probe method for the GPIO device.
261 * @pdev: pointer to the platform device
262 *
263 * Return:
264 * It returns 0, if the driver is bound to the GPIO device, or
265 * a negative value if there is an error.
266 */
267static int xgpio_probe(struct platform_device *pdev)
268{
269 struct xgpio_instance *chip;
270 int status = 0;
271 struct device_node *np = pdev->dev.of_node;
272 u32 is_dual;
273
274 chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
275 if (!chip)
276 return -ENOMEM;
277
278 platform_set_drvdata(pdev, chip);
279
280 /* Update GPIO state shadow register with default value */
281 of_property_read_u32(np, "xlnx,dout-default", &chip->gpio_state[0]);
282
283 /* Update GPIO direction shadow register with default value */
284 if (of_property_read_u32(np, "xlnx,tri-default", &chip->gpio_dir[0]))
285 chip->gpio_dir[0] = 0xFFFFFFFF;
286
287 /*
288 * Check device node and parent device node for device width
289 * and assume default width of 32
290 */
291 if (of_property_read_u32(np, "xlnx,gpio-width", &chip->gpio_width[0]))
292 chip->gpio_width[0] = 32;
293
294 spin_lock_init(&chip->gpio_lock[0]);
295
296 if (of_property_read_u32(np, "xlnx,is-dual", &is_dual))
297 is_dual = 0;
298
299 if (is_dual) {
300 /* Update GPIO state shadow register with default value */
301 of_property_read_u32(np, "xlnx,dout-default-2",
302 &chip->gpio_state[1]);
303
304 /* Update GPIO direction shadow register with default value */
305 if (of_property_read_u32(np, "xlnx,tri-default-2",
306 &chip->gpio_dir[1]))
307 chip->gpio_dir[1] = 0xFFFFFFFF;
308
309 /*
310 * Check device node and parent device node for device width
311 * and assume default width of 32
312 */
313 if (of_property_read_u32(np, "xlnx,gpio2-width",
314 &chip->gpio_width[1]))
315 chip->gpio_width[1] = 32;
316
317 spin_lock_init(&chip->gpio_lock[1]);
318 }
319
320 chip->gc.base = -1;
321 chip->gc.ngpio = chip->gpio_width[0] + chip->gpio_width[1];
322 chip->gc.parent = &pdev->dev;
323 chip->gc.direction_input = xgpio_dir_in;
324 chip->gc.direction_output = xgpio_dir_out;
325 chip->gc.get = xgpio_get;
326 chip->gc.set = xgpio_set;
327 chip->gc.set_multiple = xgpio_set_multiple;
328
329 chip->gc.label = dev_name(&pdev->dev);
330
331 chip->regs = devm_platform_ioremap_resource(pdev, 0);
332 if (IS_ERR(chip->regs)) {
333 dev_err(&pdev->dev, "failed to ioremap memory resource\n");
334 return PTR_ERR(chip->regs);
335 }
336
337 xgpio_save_regs(chip);
338
339 status = devm_gpiochip_add_data(&pdev->dev, &chip->gc, chip);
340 if (status) {
341 dev_err(&pdev->dev, "failed to add GPIO chip\n");
342 return status;
343 }
344
345 return 0;
346}
347
348static const struct of_device_id xgpio_of_match[] = {
349 { .compatible = "xlnx,xps-gpio-1.00.a", },
350 { /* end of list */ },
351};
352
353MODULE_DEVICE_TABLE(of, xgpio_of_match);
354
355static struct platform_driver xgpio_plat_driver = {
356 .probe = xgpio_probe,
357 .driver = {
358 .name = "gpio-xilinx",
359 .of_match_table = xgpio_of_match,
360 },
361};
362
363static int __init xgpio_init(void)
364{
365 return platform_driver_register(&xgpio_plat_driver);
366}
367
368subsys_initcall(xgpio_init);
369
370static void __exit xgpio_exit(void)
371{
372 platform_driver_unregister(&xgpio_plat_driver);
373}
374module_exit(xgpio_exit);
375
376MODULE_AUTHOR("Xilinx, Inc.");
377MODULE_DESCRIPTION("Xilinx GPIO driver");
378MODULE_LICENSE("GPL");