1 /*
2 * linux/arch/arm/mach-w90x900/gpio.c
3 *
4 * Generic nuc900 GPIO handling
5 *
6 * Wan ZongShun <mcuos.com@gmail.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13 #include <linux/clk.h>
14 #include <linux/errno.h>
15 #include <linux/interrupt.h>
16 #include <linux/irq.h>
17 #include <linux/debugfs.h>
18 #include <linux/seq_file.h>
19 #include <linux/kernel.h>
20 #include <linux/list.h>
21 #include <linux/module.h>
22 #include <linux/io.h>
23 #include <linux/gpio/driver.h>
24
25 #include <mach/hardware.h>
26
27 #define GPIO_BASE (W90X900_VA_GPIO)
28 #define GPIO_DIR (0x04)
29 #define GPIO_OUT (0x08)
30 #define GPIO_IN (0x0C)
31 #define GROUPINERV (0x10)
32 #define GPIO_GPIO(Nb) (0x00000001 << (Nb))
33
34 #define NUC900_GPIO_CHIP(name, base_gpio, nr_gpio) \
35 { \
36 .chip = { \
37 .label = name, \
38 .direction_input = nuc900_dir_input, \
39 .direction_output = nuc900_dir_output, \
40 .get = nuc900_gpio_get, \
41 .set = nuc900_gpio_set, \
42 .base = base_gpio, \
43 .ngpio = nr_gpio, \
44 } \
45 }
46
47 struct nuc900_gpio_chip {
48 struct gpio_chip chip;
49 void __iomem *regbase; /* Base of group register*/
50 spinlock_t gpio_lock;
51 };
52
nuc900_gpio_get(struct gpio_chip * chip,unsigned offset)53 static int nuc900_gpio_get(struct gpio_chip *chip, unsigned offset)
54 {
55 struct nuc900_gpio_chip *nuc900_gpio = gpiochip_get_data(chip);
56 void __iomem *pio = nuc900_gpio->regbase + GPIO_IN;
57 unsigned int regval;
58
59 regval = __raw_readl(pio);
60 regval &= GPIO_GPIO(offset);
61
62 return (regval != 0);
63 }
64
nuc900_gpio_set(struct gpio_chip * chip,unsigned offset,int val)65 static void nuc900_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
66 {
67 struct nuc900_gpio_chip *nuc900_gpio = gpiochip_get_data(chip);
68 void __iomem *pio = nuc900_gpio->regbase + GPIO_OUT;
69 unsigned int regval;
70 unsigned long flags;
71
72 spin_lock_irqsave(&nuc900_gpio->gpio_lock, flags);
73
74 regval = __raw_readl(pio);
75
76 if (val)
77 regval |= GPIO_GPIO(offset);
78 else
79 regval &= ~GPIO_GPIO(offset);
80
81 __raw_writel(regval, pio);
82
83 spin_unlock_irqrestore(&nuc900_gpio->gpio_lock, flags);
84 }
85
nuc900_dir_input(struct gpio_chip * chip,unsigned offset)86 static int nuc900_dir_input(struct gpio_chip *chip, unsigned offset)
87 {
88 struct nuc900_gpio_chip *nuc900_gpio = gpiochip_get_data(chip);
89 void __iomem *pio = nuc900_gpio->regbase + GPIO_DIR;
90 unsigned int regval;
91 unsigned long flags;
92
93 spin_lock_irqsave(&nuc900_gpio->gpio_lock, flags);
94
95 regval = __raw_readl(pio);
96 regval &= ~GPIO_GPIO(offset);
97 __raw_writel(regval, pio);
98
99 spin_unlock_irqrestore(&nuc900_gpio->gpio_lock, flags);
100
101 return 0;
102 }
103
nuc900_dir_output(struct gpio_chip * chip,unsigned offset,int val)104 static int nuc900_dir_output(struct gpio_chip *chip, unsigned offset, int val)
105 {
106 struct nuc900_gpio_chip *nuc900_gpio = gpiochip_get_data(chip);
107 void __iomem *outreg = nuc900_gpio->regbase + GPIO_OUT;
108 void __iomem *pio = nuc900_gpio->regbase + GPIO_DIR;
109 unsigned int regval;
110 unsigned long flags;
111
112 spin_lock_irqsave(&nuc900_gpio->gpio_lock, flags);
113
114 regval = __raw_readl(pio);
115 regval |= GPIO_GPIO(offset);
116 __raw_writel(regval, pio);
117
118 regval = __raw_readl(outreg);
119
120 if (val)
121 regval |= GPIO_GPIO(offset);
122 else
123 regval &= ~GPIO_GPIO(offset);
124
125 __raw_writel(regval, outreg);
126
127 spin_unlock_irqrestore(&nuc900_gpio->gpio_lock, flags);
128
129 return 0;
130 }
131
132 static struct nuc900_gpio_chip nuc900_gpio[] = {
133 NUC900_GPIO_CHIP("GROUPC", 0, 16),
134 NUC900_GPIO_CHIP("GROUPD", 16, 10),
135 NUC900_GPIO_CHIP("GROUPE", 26, 14),
136 NUC900_GPIO_CHIP("GROUPF", 40, 10),
137 NUC900_GPIO_CHIP("GROUPG", 50, 17),
138 NUC900_GPIO_CHIP("GROUPH", 67, 8),
139 NUC900_GPIO_CHIP("GROUPI", 75, 17),
140 };
141
nuc900_init_gpio(int nr_group)142 void __init nuc900_init_gpio(int nr_group)
143 {
144 unsigned i;
145 struct nuc900_gpio_chip *gpio_chip;
146
147 for (i = 0; i < nr_group; i++) {
148 gpio_chip = &nuc900_gpio[i];
149 spin_lock_init(&gpio_chip->gpio_lock);
150 gpio_chip->regbase = GPIO_BASE + i * GROUPINERV;
151 gpiochip_add_data(&gpio_chip->chip, gpio_chip);
152 }
153 }
154
