aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/gpio/gpio-xgene-sb.c
blob: b6a15c39293e2ad0e7ff1b2bcb323d4d66407085 (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
/*
 * AppliedMicro X-Gene SoC GPIO-Standby Driver
 *
 * Copyright (c) 2014, Applied Micro Circuits Corporation
 * Author: 	Tin Huynh <tnhuynh@apm.com>.
 * 		Y Vo <yvo@apm.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, see <http://www.gnu.org/licenses/>.
 */

#include <linux/module.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/of_gpio.h>
#include <linux/gpio.h>
#include <linux/gpio/driver.h>
#include <linux/basic_mmio_gpio.h>

#define XGENE_MAX_GPIO_DS		22
#define XGENE_MAX_GPIO_DS_IRQ		6

#define GPIO_MASK(x)			(1U << ((x) % 32))

#define MPA_GPIO_INT_LVL		0x0290
#define MPA_GPIO_OE_ADDR		0x029c
#define MPA_GPIO_OUT_ADDR		0x02a0
#define MPA_GPIO_IN_ADDR 		0x02a4
#define MPA_GPIO_SEL_LO 		0x0294

/**
 * struct xgene_gpio_sb - GPIO-Standby private data structure.
 * @bgc:			memory-mapped GPIO controllers.
 * @irq:			Mapping GPIO pins and interrupt number
 * nirq:			Number of GPIO pins that supports interrupt
 */
struct xgene_gpio_sb {
	struct bgpio_chip	bgc;
	u32 *irq;
	u32 nirq;
};

static inline struct xgene_gpio_sb *to_xgene_gpio_sb(struct gpio_chip *gc)
{
	struct bgpio_chip *bgc = to_bgpio_chip(gc);

	return container_of(bgc, struct xgene_gpio_sb, bgc);
}

static void xgene_gpio_set_bit(struct bgpio_chip *bgc, void __iomem *reg, u32 gpio, int val)
{
	u32 data;

	data = bgc->read_reg(reg);
	if (val)
		data |= GPIO_MASK(gpio);
	else
		data &= ~GPIO_MASK(gpio);
	bgc->write_reg(reg, data);
}

static int apm_gpio_sb_to_irq(struct gpio_chip *gc, u32 gpio)
{
	struct xgene_gpio_sb *priv = to_xgene_gpio_sb(gc);

	if (priv->irq[gpio])
		return priv->irq[gpio];

	return -ENXIO;
}

static int xgene_gpio_sb_probe(struct platform_device *pdev)
{
	struct xgene_gpio_sb *priv;
	u32 ret, i;
	u32 default_lines[] = {0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D};
	struct resource *res;
	void __iomem *regs;

	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	regs = devm_ioremap_resource(&pdev->dev, res);
	if (!regs)
		return PTR_ERR(regs);

	ret = bgpio_init(&priv->bgc, &pdev->dev, 4,
			regs + MPA_GPIO_IN_ADDR,
			regs + MPA_GPIO_OUT_ADDR, NULL,
			regs + MPA_GPIO_OE_ADDR, NULL, 0);
        if (ret)
                return ret;

	priv->bgc.gc.to_irq = apm_gpio_sb_to_irq;
	priv->bgc.gc.ngpio = XGENE_MAX_GPIO_DS;

	priv->nirq = XGENE_MAX_GPIO_DS_IRQ;

	priv->irq = devm_kzalloc(&pdev->dev, sizeof(u32) * XGENE_MAX_GPIO_DS,
				   GFP_KERNEL);
	if (!priv->irq)
		return -ENOMEM;
	memset(priv->irq, 0, sizeof(u32) * XGENE_MAX_GPIO_DS);

	for (i = 0; i < priv->nirq; i++) {
		priv->irq[default_lines[i]] = platform_get_irq(pdev, i);
		xgene_gpio_set_bit(&priv->bgc, regs + MPA_GPIO_SEL_LO,
                                   default_lines[i] * 2, 1);
		xgene_gpio_set_bit(&priv->bgc, regs + MPA_GPIO_INT_LVL, i, 1);
	}

	platform_set_drvdata(pdev, priv);

	ret = gpiochip_add(&priv->bgc.gc);
	if (ret)
		dev_err(&pdev->dev, "failed to register X-Gene GPIO Standby driver\n");
	else
		dev_info(&pdev->dev, "X-Gene GPIO Standby driver registered\n");

	return ret;
}

static int xgene_gpio_sb_remove(struct platform_device *pdev)
{
	struct xgene_gpio_sb *priv = platform_get_drvdata(pdev);

	return bgpio_remove(&priv->bgc);
}

static const struct of_device_id xgene_gpio_sb_of_match[] = {
	{.compatible = "apm,xgene-gpio-sb", },
	{},
};
MODULE_DEVICE_TABLE(of, xgene_gpio_sb_of_match);

static struct platform_driver xgene_gpio_sb_driver = {
	.driver = {
		   .name = "xgene-gpio-sb",
		   .of_match_table = xgene_gpio_sb_of_match,
		   },
	.probe = xgene_gpio_sb_probe,
	.remove = xgene_gpio_sb_remove,
};
module_platform_driver(xgene_gpio_sb_driver);

MODULE_AUTHOR("AppliedMicro");
MODULE_DESCRIPTION("APM X-Gene GPIO Standby driver");
MODULE_LICENSE("GPL");