diff options
Diffstat (limited to 'arch/sh/boards/mach-x3proto/gpio.c')
-rw-r--r-- | arch/sh/boards/mach-x3proto/gpio.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/arch/sh/boards/mach-x3proto/gpio.c b/arch/sh/boards/mach-x3proto/gpio.c new file mode 100644 index 000000000000..239e74066253 --- /dev/null +++ b/arch/sh/boards/mach-x3proto/gpio.c | |||
@@ -0,0 +1,136 @@ | |||
1 | /* | ||
2 | * arch/sh/boards/mach-x3proto/gpio.c | ||
3 | * | ||
4 | * Renesas SH-X3 Prototype Baseboard GPIO Support. | ||
5 | * | ||
6 | * Copyright (C) 2010 Paul Mundt | ||
7 | * | ||
8 | * This file is subject to the terms and conditions of the GNU General Public | ||
9 | * License. See the file "COPYING" in the main directory of this archive | ||
10 | * for more details. | ||
11 | */ | ||
12 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | ||
13 | |||
14 | #include <linux/init.h> | ||
15 | #include <linux/interrupt.h> | ||
16 | #include <linux/gpio.h> | ||
17 | #include <linux/irq.h> | ||
18 | #include <linux/kernel.h> | ||
19 | #include <linux/spinlock.h> | ||
20 | #include <linux/io.h> | ||
21 | #include <mach/ilsel.h> | ||
22 | #include <mach/hardware.h> | ||
23 | |||
24 | #define KEYCTLR 0xb81c0000 | ||
25 | #define KEYOUTR 0xb81c0002 | ||
26 | #define KEYDETR 0xb81c0004 | ||
27 | |||
28 | static DEFINE_SPINLOCK(x3proto_gpio_lock); | ||
29 | static unsigned int x3proto_gpio_irq_map[NR_BASEBOARD_GPIOS] = { 0, }; | ||
30 | |||
31 | static int x3proto_gpio_direction_input(struct gpio_chip *chip, unsigned gpio) | ||
32 | { | ||
33 | unsigned long flags; | ||
34 | unsigned int data; | ||
35 | |||
36 | spin_lock_irqsave(&x3proto_gpio_lock, flags); | ||
37 | data = __raw_readw(KEYCTLR); | ||
38 | data |= (1 << gpio); | ||
39 | __raw_writew(data, KEYCTLR); | ||
40 | spin_unlock_irqrestore(&x3proto_gpio_lock, flags); | ||
41 | |||
42 | return 0; | ||
43 | } | ||
44 | |||
45 | static int x3proto_gpio_get(struct gpio_chip *chip, unsigned gpio) | ||
46 | { | ||
47 | return !!(__raw_readw(KEYDETR) & (1 << gpio)); | ||
48 | } | ||
49 | |||
50 | static int x3proto_gpio_to_irq(struct gpio_chip *chip, unsigned gpio) | ||
51 | { | ||
52 | return x3proto_gpio_irq_map[gpio]; | ||
53 | } | ||
54 | |||
55 | static void x3proto_gpio_irq_handler(unsigned int irq, struct irq_desc *desc) | ||
56 | { | ||
57 | struct irq_data *data = irq_get_irq_data(irq); | ||
58 | struct irq_chip *chip = irq_data_get_irq_chip(data); | ||
59 | unsigned long mask; | ||
60 | int pin; | ||
61 | |||
62 | chip->irq_mask_ack(data); | ||
63 | |||
64 | mask = __raw_readw(KEYDETR); | ||
65 | |||
66 | for_each_set_bit(pin, &mask, NR_BASEBOARD_GPIOS) | ||
67 | generic_handle_irq(x3proto_gpio_to_irq(NULL, pin)); | ||
68 | |||
69 | chip->irq_unmask(data); | ||
70 | } | ||
71 | |||
72 | struct gpio_chip x3proto_gpio_chip = { | ||
73 | .label = "x3proto-gpio", | ||
74 | .direction_input = x3proto_gpio_direction_input, | ||
75 | .get = x3proto_gpio_get, | ||
76 | .to_irq = x3proto_gpio_to_irq, | ||
77 | .base = -1, | ||
78 | .ngpio = NR_BASEBOARD_GPIOS, | ||
79 | }; | ||
80 | |||
81 | int __init x3proto_gpio_setup(void) | ||
82 | { | ||
83 | int ilsel; | ||
84 | int ret, i; | ||
85 | |||
86 | ilsel = ilsel_enable(ILSEL_KEY); | ||
87 | if (unlikely(ilsel < 0)) | ||
88 | return ilsel; | ||
89 | |||
90 | ret = gpiochip_add(&x3proto_gpio_chip); | ||
91 | if (unlikely(ret)) | ||
92 | goto err_gpio; | ||
93 | |||
94 | for (i = 0; i < NR_BASEBOARD_GPIOS; i++) { | ||
95 | unsigned long flags; | ||
96 | int irq = create_irq(); | ||
97 | |||
98 | if (unlikely(irq < 0)) { | ||
99 | ret = -EINVAL; | ||
100 | goto err_irq; | ||
101 | } | ||
102 | |||
103 | spin_lock_irqsave(&x3proto_gpio_lock, flags); | ||
104 | x3proto_gpio_irq_map[i] = irq; | ||
105 | set_irq_chip_and_handler_name(irq, &dummy_irq_chip, | ||
106 | handle_simple_irq, "gpio"); | ||
107 | spin_unlock_irqrestore(&x3proto_gpio_lock, flags); | ||
108 | } | ||
109 | |||
110 | pr_info("registering '%s' support, handling GPIOs %u -> %u, " | ||
111 | "bound to IRQ %u\n", | ||
112 | x3proto_gpio_chip.label, x3proto_gpio_chip.base, | ||
113 | x3proto_gpio_chip.base + x3proto_gpio_chip.ngpio, | ||
114 | ilsel); | ||
115 | |||
116 | set_irq_chained_handler(ilsel, x3proto_gpio_irq_handler); | ||
117 | set_irq_wake(ilsel, 1); | ||
118 | |||
119 | return 0; | ||
120 | |||
121 | err_irq: | ||
122 | for (; i >= 0; --i) | ||
123 | if (x3proto_gpio_irq_map[i]) | ||
124 | destroy_irq(x3proto_gpio_irq_map[i]); | ||
125 | |||
126 | ret = gpiochip_remove(&x3proto_gpio_chip); | ||
127 | if (unlikely(ret)) | ||
128 | pr_err("Failed deregistering GPIO\n"); | ||
129 | |||
130 | err_gpio: | ||
131 | synchronize_irq(ilsel); | ||
132 | |||
133 | ilsel_disable(ILSEL_KEY); | ||
134 | |||
135 | return ret; | ||
136 | } | ||