xref: /linux/arch/mips/bcm63xx/gpio.c (revision cc04a46f11ea046ed53e2c832ae29e4790f7e35f)
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/module.h>
12 #include <linux/spinlock.h>
13 #include <linux/platform_device.h>
14 #include <linux/gpio.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 
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 
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 
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 
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 
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 
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 
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(&bcm63xx_gpio_chip);
151 }
152