1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
7 * Copyright (C) 2008-2011 Florian Fainelli <florian@openwrt.org>
8 */
9
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/spinlock.h>
13 #include <linux/platform_device.h>
14 #include <linux/gpio/driver.h>
15
16 #include <bcm63xx_cpu.h>
17 #include <bcm63xx_gpio.h>
18 #include <bcm63xx_io.h>
19 #include <bcm63xx_regs.h>
20
21 static u32 gpio_out_low_reg;
22
bcm63xx_gpio_out_low_reg_init(void)23 static void bcm63xx_gpio_out_low_reg_init(void)
24 {
25 switch (bcm63xx_get_cpu_id()) {
26 case BCM6345_CPU_ID:
27 gpio_out_low_reg = GPIO_DATA_LO_REG_6345;
28 break;
29 default:
30 gpio_out_low_reg = GPIO_DATA_LO_REG;
31 break;
32 }
33 }
34
35 static DEFINE_SPINLOCK(bcm63xx_gpio_lock);
36 static u32 gpio_out_low, gpio_out_high;
37
bcm63xx_gpio_set(struct gpio_chip * chip,unsigned gpio,int val)38 static void bcm63xx_gpio_set(struct gpio_chip *chip,
39 unsigned gpio, int val)
40 {
41 u32 reg;
42 u32 mask;
43 u32 *v;
44 unsigned long flags;
45
46 if (gpio >= chip->ngpio)
47 BUG();
48
49 if (gpio < 32) {
50 reg = gpio_out_low_reg;
51 mask = 1 << gpio;
52 v = &gpio_out_low;
53 } else {
54 reg = GPIO_DATA_HI_REG;
55 mask = 1 << (gpio - 32);
56 v = &gpio_out_high;
57 }
58
59 spin_lock_irqsave(&bcm63xx_gpio_lock, flags);
60 if (val)
61 *v |= mask;
62 else
63 *v &= ~mask;
64 bcm_gpio_writel(*v, reg);
65 spin_unlock_irqrestore(&bcm63xx_gpio_lock, flags);
66 }
67
bcm63xx_gpio_get(struct gpio_chip * chip,unsigned gpio)68 static int bcm63xx_gpio_get(struct gpio_chip *chip, unsigned gpio)
69 {
70 u32 reg;
71 u32 mask;
72
73 if (gpio >= chip->ngpio)
74 BUG();
75
76 if (gpio < 32) {
77 reg = gpio_out_low_reg;
78 mask = 1 << gpio;
79 } else {
80 reg = GPIO_DATA_HI_REG;
81 mask = 1 << (gpio - 32);
82 }
83
84 return !!(bcm_gpio_readl(reg) & mask);
85 }
86
bcm63xx_gpio_set_direction(struct gpio_chip * chip,unsigned gpio,int dir)87 static int bcm63xx_gpio_set_direction(struct gpio_chip *chip,
88 unsigned gpio, int dir)
89 {
90 u32 reg;
91 u32 mask;
92 u32 tmp;
93 unsigned long flags;
94
95 if (gpio >= chip->ngpio)
96 BUG();
97
98 if (gpio < 32) {
99 reg = GPIO_CTL_LO_REG;
100 mask = 1 << gpio;
101 } else {
102 reg = GPIO_CTL_HI_REG;
103 mask = 1 << (gpio - 32);
104 }
105
106 spin_lock_irqsave(&bcm63xx_gpio_lock, flags);
107 tmp = bcm_gpio_readl(reg);
108 if (dir == BCM63XX_GPIO_DIR_IN)
109 tmp &= ~mask;
110 else
111 tmp |= mask;
112 bcm_gpio_writel(tmp, reg);
113 spin_unlock_irqrestore(&bcm63xx_gpio_lock, flags);
114
115 return 0;
116 }
117
bcm63xx_gpio_direction_input(struct gpio_chip * chip,unsigned gpio)118 static int bcm63xx_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
119 {
120 return bcm63xx_gpio_set_direction(chip, gpio, BCM63XX_GPIO_DIR_IN);
121 }
122
bcm63xx_gpio_direction_output(struct gpio_chip * chip,unsigned gpio,int value)123 static int bcm63xx_gpio_direction_output(struct gpio_chip *chip,
124 unsigned gpio, int value)
125 {
126 bcm63xx_gpio_set(chip, gpio, value);
127 return bcm63xx_gpio_set_direction(chip, gpio, BCM63XX_GPIO_DIR_OUT);
128 }
129
130
131 static struct gpio_chip bcm63xx_gpio_chip = {
132 .label = "bcm63xx-gpio",
133 .direction_input = bcm63xx_gpio_direction_input,
134 .direction_output = bcm63xx_gpio_direction_output,
135 .get = bcm63xx_gpio_get,
136 .set = bcm63xx_gpio_set,
137 .base = 0,
138 };
139
bcm63xx_gpio_init(void)140 int __init bcm63xx_gpio_init(void)
141 {
142 bcm63xx_gpio_out_low_reg_init();
143
144 gpio_out_low = bcm_gpio_readl(gpio_out_low_reg);
145 if (!BCMCPU_IS_6345())
146 gpio_out_high = bcm_gpio_readl(GPIO_DATA_HI_REG);
147 bcm63xx_gpio_chip.ngpio = bcm63xx_gpio_count();
148 pr_info("registering %d GPIOs\n", bcm63xx_gpio_chip.ngpio);
149
150 return gpiochip_add_data(&bcm63xx_gpio_chip, NULL);
151 }
152