xref: /linux/arch/mips/bcm63xx/gpio.c (revision 67faad74352d1ce0c1f411f92fdb1e0c0f3c9380)
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 int gpio,int val)38 static int bcm63xx_gpio_set(struct gpio_chip *chip, unsigned int gpio, int val)
39 {
40 	u32 reg;
41 	u32 mask;
42 	u32 *v;
43 	unsigned long flags;
44 
45 	BUG_ON(gpio >= chip->ngpio);
46 
47 	if (gpio < 32) {
48 		reg = gpio_out_low_reg;
49 		mask = 1 << gpio;
50 		v = &gpio_out_low;
51 	} else {
52 		reg = GPIO_DATA_HI_REG;
53 		mask = 1 << (gpio - 32);
54 		v = &gpio_out_high;
55 	}
56 
57 	spin_lock_irqsave(&bcm63xx_gpio_lock, flags);
58 	if (val)
59 		*v |= mask;
60 	else
61 		*v &= ~mask;
62 	bcm_gpio_writel(*v, reg);
63 	spin_unlock_irqrestore(&bcm63xx_gpio_lock, flags);
64 
65 	return 0;
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 	BUG_ON(gpio >= chip->ngpio);
74 
75 	if (gpio < 32) {
76 		reg = gpio_out_low_reg;
77 		mask = 1 << gpio;
78 	} else {
79 		reg = GPIO_DATA_HI_REG;
80 		mask = 1 << (gpio - 32);
81 	}
82 
83 	return !!(bcm_gpio_readl(reg) & mask);
84 }
85 
bcm63xx_gpio_set_direction(struct gpio_chip * chip,unsigned gpio,int dir)86 static int bcm63xx_gpio_set_direction(struct gpio_chip *chip,
87 				      unsigned gpio, int dir)
88 {
89 	u32 reg;
90 	u32 mask;
91 	u32 tmp;
92 	unsigned long flags;
93 
94 	BUG_ON(gpio >= chip->ngpio);
95 
96 	if (gpio < 32) {
97 		reg = GPIO_CTL_LO_REG;
98 		mask = 1 << gpio;
99 	} else {
100 		reg = GPIO_CTL_HI_REG;
101 		mask = 1 << (gpio - 32);
102 	}
103 
104 	spin_lock_irqsave(&bcm63xx_gpio_lock, flags);
105 	tmp = bcm_gpio_readl(reg);
106 	if (dir == BCM63XX_GPIO_DIR_IN)
107 		tmp &= ~mask;
108 	else
109 		tmp |= mask;
110 	bcm_gpio_writel(tmp, reg);
111 	spin_unlock_irqrestore(&bcm63xx_gpio_lock, flags);
112 
113 	return 0;
114 }
115 
bcm63xx_gpio_direction_input(struct gpio_chip * chip,unsigned gpio)116 static int bcm63xx_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
117 {
118 	return bcm63xx_gpio_set_direction(chip, gpio, BCM63XX_GPIO_DIR_IN);
119 }
120 
bcm63xx_gpio_direction_output(struct gpio_chip * chip,unsigned gpio,int value)121 static int bcm63xx_gpio_direction_output(struct gpio_chip *chip,
122 					 unsigned gpio, int value)
123 {
124 	bcm63xx_gpio_set(chip, gpio, value);
125 	return bcm63xx_gpio_set_direction(chip, gpio, BCM63XX_GPIO_DIR_OUT);
126 }
127 
128 
129 static struct gpio_chip bcm63xx_gpio_chip = {
130 	.label			= "bcm63xx-gpio",
131 	.direction_input	= bcm63xx_gpio_direction_input,
132 	.direction_output	= bcm63xx_gpio_direction_output,
133 	.get			= bcm63xx_gpio_get,
134 	.set_rv			= bcm63xx_gpio_set,
135 	.base			= 0,
136 };
137 
bcm63xx_gpio_init(void)138 int __init bcm63xx_gpio_init(void)
139 {
140 	bcm63xx_gpio_out_low_reg_init();
141 
142 	gpio_out_low = bcm_gpio_readl(gpio_out_low_reg);
143 	if (!BCMCPU_IS_6345())
144 		gpio_out_high = bcm_gpio_readl(GPIO_DATA_HI_REG);
145 	bcm63xx_gpio_chip.ngpio = bcm63xx_gpio_count();
146 	pr_info("registering %d GPIOs\n", bcm63xx_gpio_chip.ngpio);
147 
148 	return gpiochip_add_data(&bcm63xx_gpio_chip, NULL);
149 }
150