Commit | Line | Data |
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d9bdffd2 PS |
1 | /* |
2 | * Support for the S1 button on Routerboard 532 | |
3 | * | |
4 | * Copyright (C) 2009 Phil Sutter <n0-1@freewrt.org> | |
5 | */ | |
6 | ||
7 | #include <linux/input-polldev.h> | |
8 | #include <linux/module.h> | |
9 | #include <linux/platform_device.h> | |
832f5dac | 10 | #include <linux/gpio.h> |
d9bdffd2 PS |
11 | |
12 | #include <asm/mach-rc32434/gpio.h> | |
13 | #include <asm/mach-rc32434/rb.h> | |
14 | ||
15 | #define DRV_NAME "rb532-button" | |
16 | ||
17 | #define RB532_BTN_RATE 100 /* msec */ | |
18 | #define RB532_BTN_KSYM BTN_0 | |
19 | ||
20 | /* The S1 button state is provided by GPIO pin 1. But as this | |
21 | * pin is also used for uart input as alternate function, the | |
22 | * operational modes must be switched first: | |
23 | * 1) disable uart using set_latch_u5() | |
24 | * 2) turn off alternate function implicitly through | |
25 | * gpio_direction_input() | |
26 | * 3) read the GPIO's current value | |
27 | * 4) undo step 2 by enabling alternate function (in this | |
28 | * mode the GPIO direction is fixed, so no change needed) | |
29 | * 5) turn on uart again | |
30 | * The GPIO value occurs to be inverted, so pin high means | |
31 | * button is not pressed. | |
32 | */ | |
33 | static bool rb532_button_pressed(void) | |
34 | { | |
35 | int val; | |
36 | ||
37 | set_latch_u5(0, LO_FOFF); | |
38 | gpio_direction_input(GPIO_BTN_S1); | |
39 | ||
40 | val = gpio_get_value(GPIO_BTN_S1); | |
41 | ||
42 | rb532_gpio_set_func(GPIO_BTN_S1); | |
43 | set_latch_u5(LO_FOFF, 0); | |
44 | ||
45 | return !val; | |
46 | } | |
47 | ||
48 | static void rb532_button_poll(struct input_polled_dev *poll_dev) | |
49 | { | |
50 | input_report_key(poll_dev->input, RB532_BTN_KSYM, | |
51 | rb532_button_pressed()); | |
52 | input_sync(poll_dev->input); | |
53 | } | |
54 | ||
5298cc4c | 55 | static int rb532_button_probe(struct platform_device *pdev) |
d9bdffd2 PS |
56 | { |
57 | struct input_polled_dev *poll_dev; | |
58 | int error; | |
59 | ||
60 | poll_dev = input_allocate_polled_device(); | |
61 | if (!poll_dev) | |
62 | return -ENOMEM; | |
63 | ||
64 | poll_dev->poll = rb532_button_poll; | |
65 | poll_dev->poll_interval = RB532_BTN_RATE; | |
66 | ||
67 | poll_dev->input->name = "rb532 button"; | |
68 | poll_dev->input->phys = "rb532/button0"; | |
69 | poll_dev->input->id.bustype = BUS_HOST; | |
70 | poll_dev->input->dev.parent = &pdev->dev; | |
71 | ||
72 | dev_set_drvdata(&pdev->dev, poll_dev); | |
73 | ||
74 | input_set_capability(poll_dev->input, EV_KEY, RB532_BTN_KSYM); | |
75 | ||
76 | error = input_register_polled_device(poll_dev); | |
77 | if (error) { | |
78 | input_free_polled_device(poll_dev); | |
79 | return error; | |
80 | } | |
81 | ||
82 | return 0; | |
83 | } | |
84 | ||
e2619cf7 | 85 | static int rb532_button_remove(struct platform_device *pdev) |
d9bdffd2 PS |
86 | { |
87 | struct input_polled_dev *poll_dev = dev_get_drvdata(&pdev->dev); | |
88 | ||
89 | input_unregister_polled_device(poll_dev); | |
90 | input_free_polled_device(poll_dev); | |
d9bdffd2 PS |
91 | |
92 | return 0; | |
93 | } | |
94 | ||
95 | static struct platform_driver rb532_button_driver = { | |
96 | .probe = rb532_button_probe, | |
1cb0aa88 | 97 | .remove = rb532_button_remove, |
d9bdffd2 PS |
98 | .driver = { |
99 | .name = DRV_NAME, | |
d9bdffd2 PS |
100 | }, |
101 | }; | |
840a746b | 102 | module_platform_driver(rb532_button_driver); |
d9bdffd2 PS |
103 | |
104 | MODULE_AUTHOR("Phil Sutter <n0-1@freewrt.org>"); | |
105 | MODULE_LICENSE("GPL"); | |
106 | MODULE_DESCRIPTION("Support for S1 button on Routerboard 532"); | |
107 | MODULE_ALIAS("platform:" DRV_NAME); |