aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/gpio/gpio-ks8695.c
blob: 464a83de0d6a48fea14125fc81134e6d1bda21f5 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
/*
 * arch/arm/mach-ks8695/gpio.c
 *
 * Copyright (C) 2006 Andrew Victor
 * Updated to GPIOLIB, Copyright 2008 Simtec Electronics
 *                     Daniel Silverstone <dsilvers@simtec.co.uk>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include <linux/gpio.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/module.h>
#include <linux/io.h>

#include <mach/hardware.h>
#include <asm/mach/irq.h>

#include <mach/regs-gpio.h>
#include <mach/gpio-ks8695.h>

/*
 * Configure a GPIO line for either GPIO function, or its internal
 * function (Interrupt, Timer, etc).
 */
static void ks8695_gpio_mode(unsigned int pin, short gpio)
{
	unsigned int enable[] = { IOPC_IOEINT0EN, IOPC_IOEINT1EN, IOPC_IOEINT2EN, IOPC_IOEINT3EN, IOPC_IOTIM0EN, IOPC_IOTIM1EN };
	unsigned long x, flags;

	if (pin > KS8695_GPIO_5)	/* only GPIO 0..5 have internal functions */
		return;

	local_irq_save(flags);

	x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPC);
	if (gpio)			/* GPIO: set bit to 0 */
		x &= ~enable[pin];
	else				/* Internal function: set bit to 1 */
		x |= enable[pin];
	__raw_writel(x, KS8695_GPIO_VA + KS8695_IOPC);

	local_irq_restore(flags);
}


static unsigned short gpio_irq[] = { KS8695_IRQ_EXTERN0, KS8695_IRQ_EXTERN1, KS8695_IRQ_EXTERN2, KS8695_IRQ_EXTERN3 };

/*
 * Configure GPIO pin as external interrupt source.
 */
int ks8695_gpio_interrupt(unsigned int pin, unsigned int type)
{
	unsigned long x, flags;

	if (pin > KS8695_GPIO_3)	/* only GPIO 0..3 can generate IRQ */
		return -EINVAL;

	local_irq_save(flags);

	/* set pin as input */
	x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM);
	x &= ~IOPM(pin);
	__raw_writel(x, KS8695_GPIO_VA + KS8695_IOPM);

	local_irq_restore(flags);

	/* Set IRQ triggering type */
	irq_set_irq_type(gpio_irq[pin], type);

	/* enable interrupt mode */
	ks8695_gpio_mode(pin, 0);

	return 0;
}
EXPORT_SYMBOL(ks8695_gpio_interrupt);



/* .... Generic GPIO interface .............................................. */

/*
 * Configure the GPIO line as an input.
 */
static int ks8695_gpio_direction_input(struct gpio_chip *gc, unsigned int pin)
{
	unsigned long x, flags;

	if (pin > KS8695_GPIO_15)
		return -EINVAL;

	/* set pin to GPIO mode */
	ks8695_gpio_mode(pin, 1);

	local_irq_save(flags);

	/* set pin as input */
	x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM);
	x &= ~IOPM(pin);
	__raw_writel(x, KS8695_GPIO_VA + KS8695_IOPM);

	local_irq_restore(flags);

	return 0;
}


/*
 * Configure the GPIO line as an output, with default state.
 */
static int ks8695_gpio_direction_output(struct gpio_chip *gc,
					unsigned int pin, int state)
{
	unsigned long x, flags;

	if (pin > KS8695_GPIO_15)
		return -EINVAL;

	/* set pin to GPIO mode */
	ks8695_gpio_mode(pin, 1);

	local_irq_save(flags);

	/* set line state */
	x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD);
	if (state)
		x |= IOPD(pin);
	else
		x &= ~IOPD(pin);
	__raw_writel(x, KS8695_GPIO_VA + KS8695_IOPD);

	/* set pin as output */
	x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM);
	x |= IOPM(pin);
	__raw_writel(x, KS8695_GPIO_VA + KS8695_IOPM);

	local_irq_restore(flags);

	return 0;
}


/*
 * Set the state of an output GPIO line.
 */
static void ks8695_gpio_set_value(struct gpio_chip *gc,
				  unsigned int pin, int state)
{
	unsigned long x, flags;

	if (pin > KS8695_GPIO_15)
		return;

	local_irq_save(flags);

	/* set output line state */
	x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD);
	if (state)
		x |= IOPD(pin);
	else
		x &= ~IOPD(pin);
	__raw_writel(x, KS8695_GPIO_VA + KS8695_IOPD);

	local_irq_restore(flags);
}


/*
 * Read the state of a GPIO line.
 */
static int ks8695_gpio_get_value(struct gpio_chip *gc, unsigned int pin)
{
	unsigned long x;

	if (pin > KS8695_GPIO_15)
		return -EINVAL;

	x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD);
	return (x & IOPD(pin)) != 0;
}


/*
 * Map GPIO line to IRQ number.
 */
static int ks8695_gpio_to_irq(struct gpio_chip *gc, unsigned int pin)
{
	if (pin > KS8695_GPIO_3)	/* only GPIO 0..3 can generate IRQ */
		return -EINVAL;

	return gpio_irq[pin];
}

/*
 * Map IRQ number to GPIO line.
 */
int irq_to_gpio(unsigned int irq)
{
	if ((irq < KS8695_IRQ_EXTERN0) || (irq > KS8695_IRQ_EXTERN3))
		return -EINVAL;

	return (irq - KS8695_IRQ_EXTERN0);
}
EXPORT_SYMBOL(irq_to_gpio);

/* GPIOLIB interface */

static struct gpio_chip ks8695_gpio_chip = {
	.label			= "KS8695",
	.direction_input	= ks8695_gpio_direction_input,
	.direction_output	= ks8695_gpio_direction_output,
	.get			= ks8695_gpio_get_value,
	.set			= ks8695_gpio_set_value,
	.to_irq			= ks8695_gpio_to_irq,
	.base			= 0,
	.ngpio			= 16,
	.can_sleep		= false,
};

/* Register the GPIOs */
void ks8695_register_gpios(void)
{
	if (gpiochip_add(&ks8695_gpio_chip))
		printk(KERN_ERR "Unable to register core GPIOs\n");
}

/* .... Debug interface ..................................................... */

#ifdef CONFIG_DEBUG_FS

static int ks8695_gpio_show(struct seq_file *s, void *unused)
{
	unsigned int enable[] = { IOPC_IOEINT0EN, IOPC_IOEINT1EN, IOPC_IOEINT2EN, IOPC_IOEINT3EN, IOPC_IOTIM0EN, IOPC_IOTIM1EN };
	unsigned int intmask[] = { IOPC_IOEINT0TM, IOPC_IOEINT1TM, IOPC_IOEINT2TM, IOPC_IOEINT3TM };
	unsigned long mode, ctrl, data;
	int i;

	mode = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM);
	ctrl = __raw_readl(KS8695_GPIO_VA + KS8695_IOPC);
	data = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD);

	seq_printf(s, "Pin\tI/O\tFunction\tState\n\n");

	for (i = KS8695_GPIO_0; i <= KS8695_GPIO_15 ; i++) {
		seq_printf(s, "%i:\t", i);

		seq_printf(s, "%s\t", (mode & IOPM(i)) ? "Output" : "Input");

		if (i <= KS8695_GPIO_3) {
			if (ctrl & enable[i]) {
				seq_printf(s, "EXT%i ", i);

				switch ((ctrl & intmask[i]) >> (4 * i)) {
					case IOPC_TM_LOW:
						seq_printf(s, "(Low)");		break;
					case IOPC_TM_HIGH:
						seq_printf(s, "(High)");	break;
					case IOPC_TM_RISING:
						seq_printf(s, "(Rising)");	break;
					case IOPC_TM_FALLING:
						seq_printf(s, "(Falling)");	break;
					case IOPC_TM_EDGE:
						seq_printf(s, "(Edges)");	break;
				}
			}
			else
				seq_printf(s, "GPIO\t");
		}
		else if (i <= KS8695_GPIO_5) {
			if (ctrl & enable[i])
				seq_printf(s, "TOUT%i\t", i - KS8695_GPIO_4);
			else
				seq_printf(s, "GPIO\t");
		}
		else
			seq_printf(s, "GPIO\t");

		seq_printf(s, "\t");

		seq_printf(s, "%i\n", (data & IOPD(i)) ? 1 : 0);
	}
	return 0;
}

static int ks8695_gpio_open(struct inode *inode, struct file *file)
{
	return single_open(file, ks8695_gpio_show, NULL);
}

static const struct file_operations ks8695_gpio_operations = {
	.open		= ks8695_gpio_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static int __init ks8695_gpio_debugfs_init(void)
{
	/* /sys/kernel/debug/ks8695_gpio */
	(void) debugfs_create_file("ks8695_gpio", S_IFREG | S_IRUGO, NULL, NULL, &ks8695_gpio_operations);
	return 0;
}
postcore_initcall(ks8695_gpio_debugfs_init);

#endif