aboutsummaryrefslogtreecommitdiff
path: root/drivers/gpio/altera_pio.c
blob: fb037607355e0486121c26ff6b26ab1423546cd4 (plain)
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
/*
 * Driver for Altera's PIO ip core
 *
 * Copyright (C) 2011  Missing Link Electronics
 *                     Joachim Foerster <joachim@missinglinkelectronics.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * 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
 *
 * To use this driver, in your board's config. header:
 * #define CONFIG_ALTERA_PIO
 * #define CONFIG_SYS_ALTERA_PIO_NUM <number-of-pio-cores>
 * #define CONFIG_SYS_ALTERA_PIO_GPIO_NUM <total-number-of-gpios>
 * And in your board's early setup routine:
 * altera_pio_init(<baseaddr>, <width>, 'i'|'o'|'t',
 *                 <reset-value>, <neg-mask>, "label");
 *  - 'i'|'o'|'t': PIO is input-only/output-only/tri-state
 *  - <reset-value>: for correct initial status display, output-only
 *  - <neg-mask> is meant to be used to in cases of active-low
 *    GPIOs, such as LEDs and buttons (on/pressed == 0). Each bit
 *    which is 1 in <neg-mask> inverts the corresponding GPIO's value
 *    before set/after get. So: gpio_set_value(gpio, 1) => LED on .
 *
 * Do NOT define CONFIG_SYS_GPIO_BASE !
 *
 * Optionally, in your board's config. header:
 * - To force a GPIO numbering scheme like in Linux ...
 * #define CONFIG_GPIO_DOWNTO_NUMBERING
 * ... starting with 255 (default)
 * #define CONFIG_GPIO_DOWNTO_MAX 255
 */
#include <common.h>
#include <asm/io.h>
#include <asm/gpio.h>

#ifdef CONFIG_GPIO_DOWNTO_NUMBERING
#ifndef CONFIG_GPIO_DOWNTO_MAX
#define CONFIG_GPIO_DOWNTO_MAX 255
#endif
#endif

#define ALTERA_PIO_DATA		0x0
#define ALTERA_PIO_DIR		0x4

#define GPIO_LABEL_SIZE		9


static struct altera_pio {
	u32 base;
	u8 width;
	char iot;
	u32 negmask;
	u32 sh_data;
	u32 sh_dir;
	int gidx;
	char label[GPIO_LABEL_SIZE];
} pios[CONFIG_SYS_ALTERA_PIO_NUM];

static int pio_num;

static struct altera_pio_gpio {
	unsigned num;
	struct altera_pio *pio;
	char reqlabel[GPIO_LABEL_SIZE];
} gpios[CONFIG_SYS_ALTERA_PIO_GPIO_NUM];

static int pio_gpio_num;


static int altera_pio_gidx(unsigned gpio)
{
	int i;

	for (i = 0; i < pio_gpio_num; ++i) {
		if (gpio == gpios[i].num)
			break;
	}
	if (i >= pio_gpio_num)
		return -1;
	return i;
}

static struct altera_pio *altera_pio_get_and_mask(unsigned gpio, u32 *mask)
{
	int gidx = altera_pio_gidx(gpio);
	if (gidx < 0)
		return NULL;
	if (mask)
		*mask = 1 << (gidx - gpios[gidx].pio->gidx);
	return gpios[gidx].pio;
}

#define altera_pio_use_gidx(_gidx, _reqlabel) \
	{ strncpy(gpios[_gidx].reqlabel, _reqlabel, GPIO_LABEL_SIZE); }
#define altera_pio_unuse_gidx(_gidx) { gpios[_gidx].reqlabel[0] = '\0'; }
#define altera_pio_is_gidx_used(_gidx) (gpios[_gidx].reqlabel[0] != '\0')

static int altera_pio_gpio_init(struct altera_pio *pio, u8 width)
{
	u8 gidx = pio_gpio_num;
	int i;

	if (!width)
		return -1;
	if ((pio_gpio_num + width) > CONFIG_SYS_ALTERA_PIO_GPIO_NUM)
		return -1;

	for (i = 0; i < width; ++i) {
#ifdef CONFIG_GPIO_DOWNTO_NUMBERING
		gpios[pio_gpio_num + i].num = \
			CONFIG_GPIO_DOWNTO_MAX + 1 - gidx - width + i;
#else
		gpios[pio_gpio_num + i].num = pio_gpio_num + i;
#endif
		gpios[pio_gpio_num + i].pio = pio;
		altera_pio_unuse_gidx(pio_gpio_num + i);
	}
	pio_gpio_num += width;
	return gidx;
}

int altera_pio_init(u32 base, u8 width, char iot, u32 rstval, u32 negmask,
		 const char *label)
{
	if (pio_num >= CONFIG_SYS_ALTERA_PIO_NUM)
		return -1;

	pios[pio_num].base = base;
	pios[pio_num].width = width;
	pios[pio_num].iot = iot;
	switch (iot) {
	case 'i':
		/* input only */
		pios[pio_num].sh_dir = 0;
		pios[pio_num].sh_data = readl(base + ALTERA_PIO_DATA);
		break;
	case 'o':
		/* output only */
		pios[pio_num].sh_dir = 0xffffffff & ((1 << width) - 1);
		pios[pio_num].sh_data = rstval;
		break;
	case 't':
		/* bidir, tri-state */
		pios[pio_num].sh_dir = readl(base + ALTERA_PIO_DIR);
		pios[pio_num].sh_data = readl(base + ALTERA_PIO_DATA);
		break;
	default:
		return -1;
	}
	pios[pio_num].negmask = negmask & ((1 << width) - 1);
	pios[pio_num].gidx = altera_pio_gpio_init(&pios[pio_num], width);
	if (pios[pio_num].gidx < 0)
		return -1;
	strncpy(pios[pio_num].label, label, GPIO_LABEL_SIZE);
	return pio_num++;
}

void altera_pio_info(void)
{
	int i;
	int j;
	int gidx;
	u32 mask;

	for (i = 0; i < pio_num; ++i) {
		printf("Altera PIO % 2d, @0x%08x, "
			"width: %u, label: %s\n",
		       i, pios[i].base, pios[i].width, pios[i].label);
		gidx = pios[i].gidx;
		for (j = gidx; j < (gidx + pios[i].width); ++j) {
			mask = 1 << (j - gidx);
			printf("\tGPIO % 4d: %s %s [%c] %s\n",
				gpios[j].num,
				gpios[j].pio->sh_dir & mask ? "out" : " in",
				gpio_get_value(gpios[j].num) ? "set" : "clr",
				altera_pio_is_gidx_used(j) ? 'x' : ' ',
				gpios[j].reqlabel);
		}
	}
}


int gpio_request(unsigned gpio, const char *label)
{
	int gidx = altera_pio_gidx(gpio);
	if (gidx < 0)
		return gidx;
	if (altera_pio_is_gidx_used(gidx))
		return -1;

	altera_pio_use_gidx(gidx, label);
	return 0;
}

int gpio_free(unsigned gpio)
{
	int gidx = altera_pio_gidx(gpio);
	if (gidx < 0)
		return gidx;
	if (!altera_pio_is_gidx_used(gidx))
		return -1;

	altera_pio_unuse_gidx(gidx);
	return 0;
}

int gpio_direction_input(unsigned gpio)
{
	u32 mask;
	struct altera_pio *pio;

	pio = altera_pio_get_and_mask(gpio, &mask);
	if (!pio)
		return -1;
	if (pio->iot == 'o')
		return -1;

	writel(pio->sh_dir &= ~mask, pio->base + ALTERA_PIO_DIR);
	return 0;
}

int gpio_direction_output(unsigned gpio, int value)
{
	u32 mask;
	struct altera_pio *pio;

	pio = altera_pio_get_and_mask(gpio, &mask);
	if (!pio)
		return -1;
	if (pio->iot == 'i')
		return -1;

	value = (pio->negmask & mask) ? !value : value;
	if (value)
		pio->sh_data |= mask;
	else
		pio->sh_data &= ~mask;
	writel(pio->sh_data, pio->base + ALTERA_PIO_DATA);
	writel(pio->sh_dir |= mask, pio->base + ALTERA_PIO_DIR);
	return 0;
}

int gpio_get_value(unsigned gpio)
{
	u32 mask;
	struct altera_pio *pio;
	u32 val;

	pio = altera_pio_get_and_mask(gpio, &mask);
	if (!pio)
		return -1;

	if ((pio->sh_dir & mask) || (pio->iot == 'o'))
		val = pio->sh_data & mask;
	else
		val = readl(pio->base + ALTERA_PIO_DATA) & mask;
	return (pio->negmask & mask) ? !val : val;
}

void gpio_set_value(unsigned gpio, int value)
{
	u32 mask;
	struct altera_pio *pio;

	pio = altera_pio_get_and_mask(gpio, &mask);
	if (!pio)
		return;
	if (pio->iot == 'i')
		return;

	value = (pio->negmask & mask) ? !value : value;
	if (value)
		pio->sh_data |= mask;
	else
		pio->sh_data &= ~mask;
	writel(pio->sh_data, pio->base + ALTERA_PIO_DATA);
	return;
}

int gpio_is_valid(int number)
{
	int gidx = altera_pio_gidx(number);

	if (gidx < 0)
		return 1;
	return 0;
}