1 /*
2  * Coldfire generic GPIO support.
3  *
4  * (C) Copyright 2009, Steven King <sfking@fdwdc.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; version 2 of the License.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  */
15 
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/sysdev.h>
19 
20 #include <asm/gpio.h>
21 #include <asm/pinmux.h>
22 #include <asm/mcfgpio.h>
23 
24 #define MCF_CHIP(chip) container_of(chip, struct mcf_gpio_chip, gpio_chip)
25 
mcf_gpio_direction_input(struct gpio_chip * chip,unsigned offset)26 int mcf_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
27 {
28 	unsigned long flags;
29 	MCFGPIO_PORTTYPE dir;
30 	struct mcf_gpio_chip *mcf_chip = MCF_CHIP(chip);
31 
32 	local_irq_save(flags);
33 	dir = mcfgpio_read(mcf_chip->pddr);
34 	dir &= ~mcfgpio_bit(chip->base + offset);
35 	mcfgpio_write(dir, mcf_chip->pddr);
36 	local_irq_restore(flags);
37 
38 	return 0;
39 }
40 
mcf_gpio_get_value(struct gpio_chip * chip,unsigned offset)41 int mcf_gpio_get_value(struct gpio_chip *chip, unsigned offset)
42 {
43 	struct mcf_gpio_chip *mcf_chip = MCF_CHIP(chip);
44 
45 	return mcfgpio_read(mcf_chip->ppdr) & mcfgpio_bit(chip->base + offset);
46 }
47 
mcf_gpio_direction_output(struct gpio_chip * chip,unsigned offset,int value)48 int mcf_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
49 		int value)
50 {
51 	unsigned long flags;
52 	MCFGPIO_PORTTYPE data;
53 	struct mcf_gpio_chip *mcf_chip = MCF_CHIP(chip);
54 
55 	local_irq_save(flags);
56 	/* write the value to the output latch */
57 	data = mcfgpio_read(mcf_chip->podr);
58 	if (value)
59 		data |= mcfgpio_bit(chip->base + offset);
60 	else
61 		data &= ~mcfgpio_bit(chip->base + offset);
62 	mcfgpio_write(data, mcf_chip->podr);
63 
64 	/* now set the direction to output */
65 	data = mcfgpio_read(mcf_chip->pddr);
66 	data |= mcfgpio_bit(chip->base + offset);
67 	mcfgpio_write(data, mcf_chip->pddr);
68 	local_irq_restore(flags);
69 
70 	return 0;
71 }
72 
mcf_gpio_set_value(struct gpio_chip * chip,unsigned offset,int value)73 void mcf_gpio_set_value(struct gpio_chip *chip, unsigned offset, int value)
74 {
75 	struct mcf_gpio_chip *mcf_chip = MCF_CHIP(chip);
76 
77 	unsigned long flags;
78 	MCFGPIO_PORTTYPE data;
79 
80 	local_irq_save(flags);
81 	data = mcfgpio_read(mcf_chip->podr);
82 	if (value)
83 		data |= mcfgpio_bit(chip->base + offset);
84 	else
85 		data &= ~mcfgpio_bit(chip->base + offset);
86 	mcfgpio_write(data, mcf_chip->podr);
87 	local_irq_restore(flags);
88 }
89 
mcf_gpio_set_value_fast(struct gpio_chip * chip,unsigned offset,int value)90 void mcf_gpio_set_value_fast(struct gpio_chip *chip, unsigned offset, int value)
91 {
92 	struct mcf_gpio_chip *mcf_chip = MCF_CHIP(chip);
93 
94 	if (value)
95 		mcfgpio_write(mcfgpio_bit(chip->base + offset), mcf_chip->setr);
96 	else
97 		mcfgpio_write(~mcfgpio_bit(chip->base + offset), mcf_chip->clrr);
98 }
99 
mcf_gpio_request(struct gpio_chip * chip,unsigned offset)100 int mcf_gpio_request(struct gpio_chip *chip, unsigned offset)
101 {
102 	struct mcf_gpio_chip *mcf_chip = MCF_CHIP(chip);
103 
104 	return mcf_chip->gpio_to_pinmux ?
105 		mcf_pinmux_request(mcf_chip->gpio_to_pinmux[offset], 0) : 0;
106 }
107 
mcf_gpio_free(struct gpio_chip * chip,unsigned offset)108 void mcf_gpio_free(struct gpio_chip *chip, unsigned offset)
109 {
110 	struct mcf_gpio_chip *mcf_chip = MCF_CHIP(chip);
111 
112 	mcf_gpio_direction_input(chip, offset);
113 
114 	if (mcf_chip->gpio_to_pinmux)
115 		mcf_pinmux_release(mcf_chip->gpio_to_pinmux[offset], 0);
116 }
117 
118 struct sysdev_class mcf_gpio_sysclass = {
119 	.name	= "gpio",
120 };
121 
mcf_gpio_sysinit(void)122 static int __init mcf_gpio_sysinit(void)
123 {
124 	return sysdev_class_register(&mcf_gpio_sysclass);
125 }
126 
127 core_initcall(mcf_gpio_sysinit);
128