Commit | Line | Data |
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3bfd5c5b HS |
1 | /* |
2 | * Driver for tilt switches connected via GPIO lines | |
3 | * not capable of generating interrupts | |
4 | * | |
5 | * Copyright (C) 2011 Heiko Stuebner <heiko@sntech.de> | |
6 | * | |
7 | * based on: drivers/input/keyboard/gpio_keys_polled.c | |
8 | * | |
9 | * Copyright (C) 2007-2010 Gabor Juhos <juhosg@openwrt.org> | |
10 | * Copyright (C) 2010 Nuno Goncalves <nunojpg@gmail.com> | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or modify | |
13 | * it under the terms of the GNU General Public License version 2 as | |
14 | * published by the Free Software Foundation. | |
15 | */ | |
16 | ||
17 | #include <linux/kernel.h> | |
18 | #include <linux/module.h> | |
3bfd5c5b HS |
19 | #include <linux/slab.h> |
20 | #include <linux/input.h> | |
21 | #include <linux/input-polldev.h> | |
22 | #include <linux/ioport.h> | |
23 | #include <linux/platform_device.h> | |
24 | #include <linux/gpio.h> | |
25 | #include <linux/input/gpio_tilt.h> | |
26 | ||
27 | #define DRV_NAME "gpio-tilt-polled" | |
28 | ||
29 | struct gpio_tilt_polled_dev { | |
30 | struct input_polled_dev *poll_dev; | |
31 | struct device *dev; | |
32 | const struct gpio_tilt_platform_data *pdata; | |
33 | ||
34 | int last_state; | |
35 | ||
36 | int threshold; | |
37 | int count; | |
38 | }; | |
39 | ||
40 | static void gpio_tilt_polled_poll(struct input_polled_dev *dev) | |
41 | { | |
42 | struct gpio_tilt_polled_dev *tdev = dev->private; | |
43 | const struct gpio_tilt_platform_data *pdata = tdev->pdata; | |
44 | struct input_dev *input = dev->input; | |
45 | struct gpio_tilt_state *tilt_state = NULL; | |
46 | int state, i; | |
47 | ||
48 | if (tdev->count < tdev->threshold) { | |
49 | tdev->count++; | |
50 | } else { | |
51 | state = 0; | |
52 | for (i = 0; i < pdata->nr_gpios; i++) | |
53 | state |= (!!gpio_get_value(pdata->gpios[i].gpio) << i); | |
54 | ||
55 | if (state != tdev->last_state) { | |
56 | for (i = 0; i < pdata->nr_states; i++) | |
57 | if (pdata->states[i].gpios == state) | |
58 | tilt_state = &pdata->states[i]; | |
59 | ||
60 | if (tilt_state) { | |
61 | for (i = 0; i < pdata->nr_axes; i++) | |
62 | input_report_abs(input, | |
63 | pdata->axes[i].axis, | |
64 | tilt_state->axes[i]); | |
65 | ||
66 | input_sync(input); | |
67 | } | |
68 | ||
69 | tdev->count = 0; | |
70 | tdev->last_state = state; | |
71 | } | |
72 | } | |
73 | } | |
74 | ||
75 | static void gpio_tilt_polled_open(struct input_polled_dev *dev) | |
76 | { | |
77 | struct gpio_tilt_polled_dev *tdev = dev->private; | |
78 | const struct gpio_tilt_platform_data *pdata = tdev->pdata; | |
79 | ||
80 | if (pdata->enable) | |
81 | pdata->enable(tdev->dev); | |
82 | ||
83 | /* report initial state of the axes */ | |
84 | tdev->last_state = -1; | |
85 | tdev->count = tdev->threshold; | |
86 | gpio_tilt_polled_poll(tdev->poll_dev); | |
87 | } | |
88 | ||
89 | static void gpio_tilt_polled_close(struct input_polled_dev *dev) | |
90 | { | |
91 | struct gpio_tilt_polled_dev *tdev = dev->private; | |
92 | const struct gpio_tilt_platform_data *pdata = tdev->pdata; | |
93 | ||
94 | if (pdata->disable) | |
95 | pdata->disable(tdev->dev); | |
96 | } | |
97 | ||
5298cc4c | 98 | static int gpio_tilt_polled_probe(struct platform_device *pdev) |
3bfd5c5b | 99 | { |
c838cb3d JH |
100 | const struct gpio_tilt_platform_data *pdata = |
101 | dev_get_platdata(&pdev->dev); | |
3bfd5c5b HS |
102 | struct device *dev = &pdev->dev; |
103 | struct gpio_tilt_polled_dev *tdev; | |
104 | struct input_polled_dev *poll_dev; | |
105 | struct input_dev *input; | |
106 | int error, i; | |
107 | ||
108 | if (!pdata || !pdata->poll_interval) | |
109 | return -EINVAL; | |
110 | ||
111 | tdev = kzalloc(sizeof(struct gpio_tilt_polled_dev), GFP_KERNEL); | |
112 | if (!tdev) { | |
113 | dev_err(dev, "no memory for private data\n"); | |
114 | return -ENOMEM; | |
115 | } | |
116 | ||
117 | error = gpio_request_array(pdata->gpios, pdata->nr_gpios); | |
118 | if (error) { | |
119 | dev_err(dev, | |
120 | "Could not request tilt GPIOs: %d\n", error); | |
121 | goto err_free_tdev; | |
122 | } | |
123 | ||
124 | poll_dev = input_allocate_polled_device(); | |
125 | if (!poll_dev) { | |
126 | dev_err(dev, "no memory for polled device\n"); | |
127 | error = -ENOMEM; | |
128 | goto err_free_gpios; | |
129 | } | |
130 | ||
131 | poll_dev->private = tdev; | |
132 | poll_dev->poll = gpio_tilt_polled_poll; | |
133 | poll_dev->poll_interval = pdata->poll_interval; | |
134 | poll_dev->open = gpio_tilt_polled_open; | |
135 | poll_dev->close = gpio_tilt_polled_close; | |
136 | ||
137 | input = poll_dev->input; | |
138 | ||
139 | input->name = pdev->name; | |
140 | input->phys = DRV_NAME"/input0"; | |
141 | input->dev.parent = &pdev->dev; | |
142 | ||
143 | input->id.bustype = BUS_HOST; | |
144 | input->id.vendor = 0x0001; | |
145 | input->id.product = 0x0001; | |
146 | input->id.version = 0x0100; | |
147 | ||
148 | __set_bit(EV_ABS, input->evbit); | |
149 | for (i = 0; i < pdata->nr_axes; i++) | |
150 | input_set_abs_params(input, pdata->axes[i].axis, | |
151 | pdata->axes[i].min, pdata->axes[i].max, | |
152 | pdata->axes[i].fuzz, pdata->axes[i].flat); | |
153 | ||
154 | tdev->threshold = DIV_ROUND_UP(pdata->debounce_interval, | |
155 | pdata->poll_interval); | |
156 | ||
157 | tdev->poll_dev = poll_dev; | |
158 | tdev->dev = dev; | |
159 | tdev->pdata = pdata; | |
160 | ||
161 | error = input_register_polled_device(poll_dev); | |
162 | if (error) { | |
163 | dev_err(dev, "unable to register polled device, err=%d\n", | |
164 | error); | |
165 | goto err_free_polldev; | |
166 | } | |
167 | ||
168 | platform_set_drvdata(pdev, tdev); | |
169 | ||
170 | return 0; | |
171 | ||
172 | err_free_polldev: | |
173 | input_free_polled_device(poll_dev); | |
174 | err_free_gpios: | |
175 | gpio_free_array(pdata->gpios, pdata->nr_gpios); | |
176 | err_free_tdev: | |
177 | kfree(tdev); | |
178 | ||
179 | return error; | |
180 | } | |
181 | ||
e2619cf7 | 182 | static int gpio_tilt_polled_remove(struct platform_device *pdev) |
3bfd5c5b HS |
183 | { |
184 | struct gpio_tilt_polled_dev *tdev = platform_get_drvdata(pdev); | |
185 | const struct gpio_tilt_platform_data *pdata = tdev->pdata; | |
186 | ||
3bfd5c5b HS |
187 | input_unregister_polled_device(tdev->poll_dev); |
188 | input_free_polled_device(tdev->poll_dev); | |
189 | ||
190 | gpio_free_array(pdata->gpios, pdata->nr_gpios); | |
191 | ||
192 | kfree(tdev); | |
193 | ||
194 | return 0; | |
195 | } | |
196 | ||
197 | static struct platform_driver gpio_tilt_polled_driver = { | |
198 | .probe = gpio_tilt_polled_probe, | |
1cb0aa88 | 199 | .remove = gpio_tilt_polled_remove, |
3bfd5c5b HS |
200 | .driver = { |
201 | .name = DRV_NAME, | |
3bfd5c5b HS |
202 | }, |
203 | }; | |
204 | ||
205 | module_platform_driver(gpio_tilt_polled_driver); | |
206 | ||
207 | MODULE_LICENSE("GPL v2"); | |
208 | MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>"); | |
209 | MODULE_DESCRIPTION("Polled GPIO tilt driver"); | |
210 | MODULE_ALIAS("platform:" DRV_NAME); |