1/*
2 *  Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
3 *  JZ4740 platform GPIO support
4 *
5 *  This program is free software; you can redistribute it and/or modify it
6 *  under  the terms of the GNU General	 Public License as published by the
7 *  Free Software Foundation;  either version 2 of the License, or (at your
8 *  option) any later version.
9 *
10 *  You should have received a copy of the GNU General Public License along
11 *  with this program; if not, write to the Free Software Foundation, Inc.,
12 *  675 Mass Ave, Cambridge, MA 02139, USA.
13 *
14 */
15
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/init.h>
19
20#include <linux/io.h>
21#include <linux/gpio.h>
22#include <linux/delay.h>
23#include <linux/interrupt.h>
24#include <linux/bitops.h>
25
26#include <linux/debugfs.h>
27#include <linux/seq_file.h>
28
29#include <asm/mach-jz4740/base.h>
30
31#include "irq.h"
32
33#define JZ4740_GPIO_BASE_A (32*0)
34#define JZ4740_GPIO_BASE_B (32*1)
35#define JZ4740_GPIO_BASE_C (32*2)
36#define JZ4740_GPIO_BASE_D (32*3)
37
38#define JZ4740_GPIO_NUM_A 32
39#define JZ4740_GPIO_NUM_B 32
40#define JZ4740_GPIO_NUM_C 31
41#define JZ4740_GPIO_NUM_D 32
42
43#define JZ4740_IRQ_GPIO_BASE_A (JZ4740_IRQ_GPIO(0) + JZ4740_GPIO_BASE_A)
44#define JZ4740_IRQ_GPIO_BASE_B (JZ4740_IRQ_GPIO(0) + JZ4740_GPIO_BASE_B)
45#define JZ4740_IRQ_GPIO_BASE_C (JZ4740_IRQ_GPIO(0) + JZ4740_GPIO_BASE_C)
46#define JZ4740_IRQ_GPIO_BASE_D (JZ4740_IRQ_GPIO(0) + JZ4740_GPIO_BASE_D)
47
48#define JZ_REG_GPIO_PIN			0x00
49#define JZ_REG_GPIO_DATA		0x10
50#define JZ_REG_GPIO_DATA_SET		0x14
51#define JZ_REG_GPIO_DATA_CLEAR		0x18
52#define JZ_REG_GPIO_MASK		0x20
53#define JZ_REG_GPIO_MASK_SET		0x24
54#define JZ_REG_GPIO_MASK_CLEAR		0x28
55#define JZ_REG_GPIO_PULL		0x30
56#define JZ_REG_GPIO_PULL_SET		0x34
57#define JZ_REG_GPIO_PULL_CLEAR		0x38
58#define JZ_REG_GPIO_FUNC		0x40
59#define JZ_REG_GPIO_FUNC_SET		0x44
60#define JZ_REG_GPIO_FUNC_CLEAR		0x48
61#define JZ_REG_GPIO_SELECT		0x50
62#define JZ_REG_GPIO_SELECT_SET		0x54
63#define JZ_REG_GPIO_SELECT_CLEAR	0x58
64#define JZ_REG_GPIO_DIRECTION		0x60
65#define JZ_REG_GPIO_DIRECTION_SET	0x64
66#define JZ_REG_GPIO_DIRECTION_CLEAR	0x68
67#define JZ_REG_GPIO_TRIGGER		0x70
68#define JZ_REG_GPIO_TRIGGER_SET		0x74
69#define JZ_REG_GPIO_TRIGGER_CLEAR	0x78
70#define JZ_REG_GPIO_FLAG		0x80
71#define JZ_REG_GPIO_FLAG_CLEAR		0x14
72
73#define GPIO_TO_BIT(gpio) BIT(gpio & 0x1f)
74#define GPIO_TO_REG(gpio, reg) (gpio_to_jz_gpio_chip(gpio)->base + (reg))
75#define CHIP_TO_REG(chip, reg) (gpio_chip_to_jz_gpio_chip(chip)->base + (reg))
76
77struct jz_gpio_chip {
78	unsigned int irq;
79	unsigned int irq_base;
80	uint32_t edge_trigger_both;
81
82	void __iomem *base;
83
84	struct gpio_chip gpio_chip;
85};
86
87static struct jz_gpio_chip jz4740_gpio_chips[];
88
89static inline struct jz_gpio_chip *gpio_to_jz_gpio_chip(unsigned int gpio)
90{
91	return &jz4740_gpio_chips[gpio >> 5];
92}
93
94static inline struct jz_gpio_chip *gpio_chip_to_jz_gpio_chip(struct gpio_chip *gpio_chip)
95{
96	return container_of(gpio_chip, struct jz_gpio_chip, gpio_chip);
97}
98
99static inline struct jz_gpio_chip *irq_to_jz_gpio_chip(struct irq_data *data)
100{
101	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
102	return gc->private;
103}
104
105static inline void jz_gpio_write_bit(unsigned int gpio, unsigned int reg)
106{
107	writel(GPIO_TO_BIT(gpio), GPIO_TO_REG(gpio, reg));
108}
109
110int jz_gpio_set_function(int gpio, enum jz_gpio_function function)
111{
112	if (function == JZ_GPIO_FUNC_NONE) {
113		jz_gpio_write_bit(gpio, JZ_REG_GPIO_FUNC_CLEAR);
114		jz_gpio_write_bit(gpio, JZ_REG_GPIO_SELECT_CLEAR);
115		jz_gpio_write_bit(gpio, JZ_REG_GPIO_TRIGGER_CLEAR);
116	} else {
117		jz_gpio_write_bit(gpio, JZ_REG_GPIO_FUNC_SET);
118		jz_gpio_write_bit(gpio, JZ_REG_GPIO_TRIGGER_CLEAR);
119		switch (function) {
120		case JZ_GPIO_FUNC1:
121			jz_gpio_write_bit(gpio, JZ_REG_GPIO_SELECT_CLEAR);
122			break;
123		case JZ_GPIO_FUNC3:
124			jz_gpio_write_bit(gpio, JZ_REG_GPIO_TRIGGER_SET);
125		case JZ_GPIO_FUNC2: /* Falltrough */
126			jz_gpio_write_bit(gpio, JZ_REG_GPIO_SELECT_SET);
127			break;
128		default:
129			BUG();
130			break;
131		}
132	}
133
134	return 0;
135}
136EXPORT_SYMBOL_GPL(jz_gpio_set_function);
137
138int jz_gpio_bulk_request(const struct jz_gpio_bulk_request *request, size_t num)
139{
140	size_t i;
141	int ret;
142
143	for (i = 0; i < num; ++i, ++request) {
144		ret = gpio_request(request->gpio, request->name);
145		if (ret)
146			goto err;
147		jz_gpio_set_function(request->gpio, request->function);
148	}
149
150	return 0;
151
152err:
153	for (--request; i > 0; --i, --request) {
154		gpio_free(request->gpio);
155		jz_gpio_set_function(request->gpio, JZ_GPIO_FUNC_NONE);
156	}
157
158	return ret;
159}
160EXPORT_SYMBOL_GPL(jz_gpio_bulk_request);
161
162void jz_gpio_bulk_free(const struct jz_gpio_bulk_request *request, size_t num)
163{
164	size_t i;
165
166	for (i = 0; i < num; ++i, ++request) {
167		gpio_free(request->gpio);
168		jz_gpio_set_function(request->gpio, JZ_GPIO_FUNC_NONE);
169	}
170
171}
172EXPORT_SYMBOL_GPL(jz_gpio_bulk_free);
173
174void jz_gpio_bulk_suspend(const struct jz_gpio_bulk_request *request, size_t num)
175{
176	size_t i;
177
178	for (i = 0; i < num; ++i, ++request) {
179		jz_gpio_set_function(request->gpio, JZ_GPIO_FUNC_NONE);
180		jz_gpio_write_bit(request->gpio, JZ_REG_GPIO_DIRECTION_CLEAR);
181		jz_gpio_write_bit(request->gpio, JZ_REG_GPIO_PULL_SET);
182	}
183}
184EXPORT_SYMBOL_GPL(jz_gpio_bulk_suspend);
185
186void jz_gpio_bulk_resume(const struct jz_gpio_bulk_request *request, size_t num)
187{
188	size_t i;
189
190	for (i = 0; i < num; ++i, ++request)
191		jz_gpio_set_function(request->gpio, request->function);
192}
193EXPORT_SYMBOL_GPL(jz_gpio_bulk_resume);
194
195void jz_gpio_enable_pullup(unsigned gpio)
196{
197	jz_gpio_write_bit(gpio, JZ_REG_GPIO_PULL_CLEAR);
198}
199EXPORT_SYMBOL_GPL(jz_gpio_enable_pullup);
200
201void jz_gpio_disable_pullup(unsigned gpio)
202{
203	jz_gpio_write_bit(gpio, JZ_REG_GPIO_PULL_SET);
204}
205EXPORT_SYMBOL_GPL(jz_gpio_disable_pullup);
206
207static int jz_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
208{
209	return !!(readl(CHIP_TO_REG(chip, JZ_REG_GPIO_PIN)) & BIT(gpio));
210}
211
212static void jz_gpio_set_value(struct gpio_chip *chip, unsigned gpio, int value)
213{
214	uint32_t __iomem *reg = CHIP_TO_REG(chip, JZ_REG_GPIO_DATA_SET);
215	reg += !value;
216	writel(BIT(gpio), reg);
217}
218
219static int jz_gpio_direction_output(struct gpio_chip *chip, unsigned gpio,
220	int value)
221{
222	writel(BIT(gpio), CHIP_TO_REG(chip, JZ_REG_GPIO_DIRECTION_SET));
223	jz_gpio_set_value(chip, gpio, value);
224
225	return 0;
226}
227
228static int jz_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
229{
230	writel(BIT(gpio), CHIP_TO_REG(chip, JZ_REG_GPIO_DIRECTION_CLEAR));
231
232	return 0;
233}
234
235int jz_gpio_port_direction_input(int port, uint32_t mask)
236{
237	writel(mask, GPIO_TO_REG(port, JZ_REG_GPIO_DIRECTION_CLEAR));
238
239	return 0;
240}
241EXPORT_SYMBOL(jz_gpio_port_direction_input);
242
243int jz_gpio_port_direction_output(int port, uint32_t mask)
244{
245	writel(mask, GPIO_TO_REG(port, JZ_REG_GPIO_DIRECTION_SET));
246
247	return 0;
248}
249EXPORT_SYMBOL(jz_gpio_port_direction_output);
250
251void jz_gpio_port_set_value(int port, uint32_t value, uint32_t mask)
252{
253	writel(~value & mask, GPIO_TO_REG(port, JZ_REG_GPIO_DATA_CLEAR));
254	writel(value & mask, GPIO_TO_REG(port, JZ_REG_GPIO_DATA_SET));
255}
256EXPORT_SYMBOL(jz_gpio_port_set_value);
257
258uint32_t jz_gpio_port_get_value(int port, uint32_t mask)
259{
260	uint32_t value = readl(GPIO_TO_REG(port, JZ_REG_GPIO_PIN));
261
262	return value & mask;
263}
264EXPORT_SYMBOL(jz_gpio_port_get_value);
265
266int gpio_to_irq(unsigned gpio)
267{
268	return JZ4740_IRQ_GPIO(0) + gpio;
269}
270EXPORT_SYMBOL_GPL(gpio_to_irq);
271
272int irq_to_gpio(unsigned irq)
273{
274	return irq - JZ4740_IRQ_GPIO(0);
275}
276EXPORT_SYMBOL_GPL(irq_to_gpio);
277
278#define IRQ_TO_BIT(irq) BIT(irq_to_gpio(irq) & 0x1f)
279
280static void jz_gpio_check_trigger_both(struct jz_gpio_chip *chip, unsigned int irq)
281{
282	uint32_t value;
283	void __iomem *reg;
284	uint32_t mask = IRQ_TO_BIT(irq);
285
286	if (!(chip->edge_trigger_both & mask))
287		return;
288
289	reg = chip->base;
290
291	value = readl(chip->base + JZ_REG_GPIO_PIN);
292	if (value & mask)
293		reg += JZ_REG_GPIO_DIRECTION_CLEAR;
294	else
295		reg += JZ_REG_GPIO_DIRECTION_SET;
296
297	writel(mask, reg);
298}
299
300static void jz_gpio_irq_demux_handler(unsigned int irq, struct irq_desc *desc)
301{
302	uint32_t flag;
303	unsigned int gpio_irq;
304	struct jz_gpio_chip *chip = irq_desc_get_handler_data(desc);
305
306	flag = readl(chip->base + JZ_REG_GPIO_FLAG);
307	if (!flag)
308		return;
309
310	gpio_irq = chip->irq_base + __fls(flag);
311
312	jz_gpio_check_trigger_both(chip, gpio_irq);
313
314	generic_handle_irq(gpio_irq);
315};
316
317static inline void jz_gpio_set_irq_bit(struct irq_data *data, unsigned int reg)
318{
319	struct jz_gpio_chip *chip = irq_to_jz_gpio_chip(data);
320	writel(IRQ_TO_BIT(data->irq), chip->base + reg);
321}
322
323static void jz_gpio_irq_unmask(struct irq_data *data)
324{
325	struct jz_gpio_chip *chip = irq_to_jz_gpio_chip(data);
326
327	jz_gpio_check_trigger_both(chip, data->irq);
328	irq_gc_unmask_enable_reg(data);
329};
330
331/* TODO: Check if function is gpio */
332static unsigned int jz_gpio_irq_startup(struct irq_data *data)
333{
334	jz_gpio_set_irq_bit(data, JZ_REG_GPIO_SELECT_SET);
335	jz_gpio_irq_unmask(data);
336	return 0;
337}
338
339static void jz_gpio_irq_shutdown(struct irq_data *data)
340{
341	irq_gc_mask_disable_reg(data);
342
343	/* Set direction to input */
344	jz_gpio_set_irq_bit(data, JZ_REG_GPIO_DIRECTION_CLEAR);
345	jz_gpio_set_irq_bit(data, JZ_REG_GPIO_SELECT_CLEAR);
346}
347
348static int jz_gpio_irq_set_type(struct irq_data *data, unsigned int flow_type)
349{
350	struct jz_gpio_chip *chip = irq_to_jz_gpio_chip(data);
351	unsigned int irq = data->irq;
352
353	if (flow_type == IRQ_TYPE_EDGE_BOTH) {
354		uint32_t value = readl(chip->base + JZ_REG_GPIO_PIN);
355		if (value & IRQ_TO_BIT(irq))
356			flow_type = IRQ_TYPE_EDGE_FALLING;
357		else
358			flow_type = IRQ_TYPE_EDGE_RISING;
359		chip->edge_trigger_both |= IRQ_TO_BIT(irq);
360	} else {
361		chip->edge_trigger_both &= ~IRQ_TO_BIT(irq);
362	}
363
364	switch (flow_type) {
365	case IRQ_TYPE_EDGE_RISING:
366		jz_gpio_set_irq_bit(data, JZ_REG_GPIO_DIRECTION_SET);
367		jz_gpio_set_irq_bit(data, JZ_REG_GPIO_TRIGGER_SET);
368		break;
369	case IRQ_TYPE_EDGE_FALLING:
370		jz_gpio_set_irq_bit(data, JZ_REG_GPIO_DIRECTION_CLEAR);
371		jz_gpio_set_irq_bit(data, JZ_REG_GPIO_TRIGGER_SET);
372		break;
373	case IRQ_TYPE_LEVEL_HIGH:
374		jz_gpio_set_irq_bit(data, JZ_REG_GPIO_DIRECTION_SET);
375		jz_gpio_set_irq_bit(data, JZ_REG_GPIO_TRIGGER_CLEAR);
376		break;
377	case IRQ_TYPE_LEVEL_LOW:
378		jz_gpio_set_irq_bit(data, JZ_REG_GPIO_DIRECTION_CLEAR);
379		jz_gpio_set_irq_bit(data, JZ_REG_GPIO_TRIGGER_CLEAR);
380		break;
381	default:
382		return -EINVAL;
383	}
384
385	return 0;
386}
387
388static int jz_gpio_irq_set_wake(struct irq_data *data, unsigned int on)
389{
390	struct jz_gpio_chip *chip = irq_to_jz_gpio_chip(data);
391
392	irq_gc_set_wake(data, on);
393	irq_set_irq_wake(chip->irq, on);
394
395	return 0;
396}
397
398#define JZ4740_GPIO_CHIP(_bank) { \
399	.irq_base = JZ4740_IRQ_GPIO_BASE_ ## _bank, \
400	.gpio_chip = { \
401		.label = "Bank " # _bank, \
402		.owner = THIS_MODULE, \
403		.set = jz_gpio_set_value, \
404		.get = jz_gpio_get_value, \
405		.direction_output = jz_gpio_direction_output, \
406		.direction_input = jz_gpio_direction_input, \
407		.base = JZ4740_GPIO_BASE_ ## _bank, \
408		.ngpio = JZ4740_GPIO_NUM_ ## _bank, \
409	}, \
410}
411
412static struct jz_gpio_chip jz4740_gpio_chips[] = {
413	JZ4740_GPIO_CHIP(A),
414	JZ4740_GPIO_CHIP(B),
415	JZ4740_GPIO_CHIP(C),
416	JZ4740_GPIO_CHIP(D),
417};
418
419static void jz4740_gpio_chip_init(struct jz_gpio_chip *chip, unsigned int id)
420{
421	struct irq_chip_generic *gc;
422	struct irq_chip_type *ct;
423
424	chip->base = ioremap(JZ4740_GPIO_BASE_ADDR + (id * 0x100), 0x100);
425
426	chip->irq = JZ4740_IRQ_INTC_GPIO(id);
427	irq_set_handler_data(chip->irq, chip);
428	irq_set_chained_handler(chip->irq, jz_gpio_irq_demux_handler);
429
430	gc = irq_alloc_generic_chip(chip->gpio_chip.label, 1, chip->irq_base,
431		chip->base, handle_level_irq);
432
433	gc->wake_enabled = IRQ_MSK(chip->gpio_chip.ngpio);
434	gc->private = chip;
435
436	ct = gc->chip_types;
437	ct->regs.enable = JZ_REG_GPIO_MASK_CLEAR;
438	ct->regs.disable = JZ_REG_GPIO_MASK_SET;
439	ct->regs.ack = JZ_REG_GPIO_FLAG_CLEAR;
440
441	ct->chip.name = "GPIO";
442	ct->chip.irq_mask = irq_gc_mask_disable_reg;
443	ct->chip.irq_unmask = jz_gpio_irq_unmask;
444	ct->chip.irq_ack = irq_gc_ack_set_bit;
445	ct->chip.irq_suspend = jz4740_irq_suspend;
446	ct->chip.irq_resume = jz4740_irq_resume;
447	ct->chip.irq_startup = jz_gpio_irq_startup;
448	ct->chip.irq_shutdown = jz_gpio_irq_shutdown;
449	ct->chip.irq_set_type = jz_gpio_irq_set_type;
450	ct->chip.irq_set_wake = jz_gpio_irq_set_wake;
451	ct->chip.flags = IRQCHIP_SET_TYPE_MASKED;
452
453	irq_setup_generic_chip(gc, IRQ_MSK(chip->gpio_chip.ngpio),
454		IRQ_GC_INIT_NESTED_LOCK, 0, IRQ_NOPROBE | IRQ_LEVEL);
455
456	gpiochip_add(&chip->gpio_chip);
457}
458
459static int __init jz4740_gpio_init(void)
460{
461	unsigned int i;
462
463	for (i = 0; i < ARRAY_SIZE(jz4740_gpio_chips); ++i)
464		jz4740_gpio_chip_init(&jz4740_gpio_chips[i], i);
465
466	printk(KERN_INFO "JZ4740 GPIO initialized\n");
467
468	return 0;
469}
470arch_initcall(jz4740_gpio_init);
471
472#ifdef CONFIG_DEBUG_FS
473
474static inline void gpio_seq_reg(struct seq_file *s, struct jz_gpio_chip *chip,
475	const char *name, unsigned int reg)
476{
477	seq_printf(s, "\t%s: %08x\n", name, readl(chip->base + reg));
478}
479
480static int gpio_regs_show(struct seq_file *s, void *unused)
481{
482	struct jz_gpio_chip *chip = jz4740_gpio_chips;
483	int i;
484
485	for (i = 0; i < ARRAY_SIZE(jz4740_gpio_chips); ++i, ++chip) {
486		seq_printf(s, "==GPIO %d==\n", i);
487		gpio_seq_reg(s, chip, "Pin", JZ_REG_GPIO_PIN);
488		gpio_seq_reg(s, chip, "Data", JZ_REG_GPIO_DATA);
489		gpio_seq_reg(s, chip, "Mask", JZ_REG_GPIO_MASK);
490		gpio_seq_reg(s, chip, "Pull", JZ_REG_GPIO_PULL);
491		gpio_seq_reg(s, chip, "Func", JZ_REG_GPIO_FUNC);
492		gpio_seq_reg(s, chip, "Select", JZ_REG_GPIO_SELECT);
493		gpio_seq_reg(s, chip, "Direction", JZ_REG_GPIO_DIRECTION);
494		gpio_seq_reg(s, chip, "Trigger", JZ_REG_GPIO_TRIGGER);
495		gpio_seq_reg(s, chip, "Flag", JZ_REG_GPIO_FLAG);
496	}
497
498	return 0;
499}
500
501static int gpio_regs_open(struct inode *inode, struct file *file)
502{
503	return single_open(file, gpio_regs_show, NULL);
504}
505
506static const struct file_operations gpio_regs_operations = {
507	.open		= gpio_regs_open,
508	.read		= seq_read,
509	.llseek		= seq_lseek,
510	.release	= single_release,
511};
512
513static int __init gpio_debugfs_init(void)
514{
515	(void) debugfs_create_file("jz_regs_gpio", S_IFREG | S_IRUGO,
516				NULL, NULL, &gpio_regs_operations);
517	return 0;
518}
519subsys_initcall(gpio_debugfs_init);
520
521#endif
522