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.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 #define to_nuc900_gpio_chip(c) container_of(c, struct nuc900_gpio_chip, chip)
34
35 #define NUC900_GPIO_CHIP(name, base_gpio, nr_gpio) \
36 { \
37 .chip = { \
38 .label = name, \
39 .direction_input = nuc900_dir_input, \
40 .direction_output = nuc900_dir_output, \
41 .get = nuc900_gpio_get, \
42 .set = nuc900_gpio_set, \
43 .base = base_gpio, \
44 .ngpio = nr_gpio, \
45 } \
46 }
47
48 struct nuc900_gpio_chip {
49 struct gpio_chip chip;
50 void __iomem *regbase; /* Base of group register*/
51 spinlock_t gpio_lock;
52 };
53
nuc900_gpio_get(struct gpio_chip * chip,unsigned offset)54 static int nuc900_gpio_get(struct gpio_chip *chip, unsigned offset)
55 {
56 struct nuc900_gpio_chip *nuc900_gpio = to_nuc900_gpio_chip(chip);
57 void __iomem *pio = nuc900_gpio->regbase + GPIO_IN;
58 unsigned int regval;
59
60 regval = __raw_readl(pio);
61 regval &= GPIO_GPIO(offset);
62
63 return (regval != 0);
64 }
65
nuc900_gpio_set(struct gpio_chip * chip,unsigned offset,int val)66 static void nuc900_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
67 {
68 struct nuc900_gpio_chip *nuc900_gpio = to_nuc900_gpio_chip(chip);
69 void __iomem *pio = nuc900_gpio->regbase + GPIO_OUT;
70 unsigned int regval;
71 unsigned long flags;
72
73 spin_lock_irqsave(&nuc900_gpio->gpio_lock, flags);
74
75 regval = __raw_readl(pio);
76
77 if (val)
78 regval |= GPIO_GPIO(offset);
79 else
80 regval &= ~GPIO_GPIO(offset);
81
82 __raw_writel(regval, pio);
83
84 spin_unlock_irqrestore(&nuc900_gpio->gpio_lock, flags);
85 }
86
nuc900_dir_input(struct gpio_chip * chip,unsigned offset)87 static int nuc900_dir_input(struct gpio_chip *chip, unsigned offset)
88 {
89 struct nuc900_gpio_chip *nuc900_gpio = to_nuc900_gpio_chip(chip);
90 void __iomem *pio = nuc900_gpio->regbase + GPIO_DIR;
91 unsigned int regval;
92 unsigned long flags;
93
94 spin_lock_irqsave(&nuc900_gpio->gpio_lock, flags);
95
96 regval = __raw_readl(pio);
97 regval &= ~GPIO_GPIO(offset);
98 __raw_writel(regval, pio);
99
100 spin_unlock_irqrestore(&nuc900_gpio->gpio_lock, flags);
101
102 return 0;
103 }
104
nuc900_dir_output(struct gpio_chip * chip,unsigned offset,int val)105 static int nuc900_dir_output(struct gpio_chip *chip, unsigned offset, int val)
106 {
107 struct nuc900_gpio_chip *nuc900_gpio = to_nuc900_gpio_chip(chip);
108 void __iomem *outreg = nuc900_gpio->regbase + GPIO_OUT;
109 void __iomem *pio = nuc900_gpio->regbase + GPIO_DIR;
110 unsigned int regval;
111 unsigned long flags;
112
113 spin_lock_irqsave(&nuc900_gpio->gpio_lock, flags);
114
115 regval = __raw_readl(pio);
116 regval |= GPIO_GPIO(offset);
117 __raw_writel(regval, pio);
118
119 regval = __raw_readl(outreg);
120
121 if (val)
122 regval |= GPIO_GPIO(offset);
123 else
124 regval &= ~GPIO_GPIO(offset);
125
126 __raw_writel(regval, outreg);
127
128 spin_unlock_irqrestore(&nuc900_gpio->gpio_lock, flags);
129
130 return 0;
131 }
132
133 static struct nuc900_gpio_chip nuc900_gpio[] = {
134 NUC900_GPIO_CHIP("GROUPC", 0, 16),
135 NUC900_GPIO_CHIP("GROUPD", 16, 10),
136 NUC900_GPIO_CHIP("GROUPE", 26, 14),
137 NUC900_GPIO_CHIP("GROUPF", 40, 10),
138 NUC900_GPIO_CHIP("GROUPG", 50, 17),
139 NUC900_GPIO_CHIP("GROUPH", 67, 8),
140 NUC900_GPIO_CHIP("GROUPI", 75, 17),
141 };
142
nuc900_init_gpio(int nr_group)143 void __init nuc900_init_gpio(int nr_group)
144 {
145 unsigned i;
146 struct nuc900_gpio_chip *gpio_chip;
147
148 for (i = 0; i < nr_group; i++) {
149 gpio_chip = &nuc900_gpio[i];
150 spin_lock_init(&gpio_chip->gpio_lock);
151 gpio_chip->regbase = GPIO_BASE + i * GROUPINERV;
152 gpiochip_add(&gpio_chip->chip);
153 }
154 }
155