1 /* 2 * Cobalt button interface driver. 3 * 4 * Copyright (C) 2007 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp> 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; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 19 */ 20 #include <linux/init.h> 21 #include <linux/input-polldev.h> 22 #include <linux/ioport.h> 23 #include <linux/module.h> 24 #include <linux/platform_device.h> 25 26 #define BUTTONS_POLL_INTERVAL 30 /* msec */ 27 #define BUTTONS_COUNT_THRESHOLD 3 28 #define BUTTONS_STATUS_MASK 0xfe000000 29 30 struct buttons_dev { 31 struct input_polled_dev *poll_dev; 32 void __iomem *reg; 33 }; 34 35 struct buttons_map { 36 uint32_t mask; 37 int keycode; 38 int count; 39 }; 40 41 static struct buttons_map buttons_map[] = { 42 { 0x02000000, KEY_RESTART, }, 43 { 0x04000000, KEY_LEFT, }, 44 { 0x08000000, KEY_UP, }, 45 { 0x10000000, KEY_DOWN, }, 46 { 0x20000000, KEY_RIGHT, }, 47 { 0x40000000, KEY_ENTER, }, 48 { 0x80000000, KEY_SELECT, }, 49 }; 50 51 static void handle_buttons(struct input_polled_dev *dev) 52 { 53 struct buttons_map *button = buttons_map; 54 struct buttons_dev *bdev = dev->private; 55 struct input_dev *input = dev->input; 56 uint32_t status; 57 int i; 58 59 status = readl(bdev->reg); 60 status = ~status & BUTTONS_STATUS_MASK; 61 62 for (i = 0; i < ARRAY_SIZE(buttons_map); i++) { 63 if (status & button->mask) { 64 button->count++; 65 } else { 66 if (button->count >= BUTTONS_COUNT_THRESHOLD) { 67 input_report_key(input, button->keycode, 0); 68 input_sync(input); 69 } 70 button->count = 0; 71 } 72 73 if (button->count == BUTTONS_COUNT_THRESHOLD) { 74 input_report_key(input, button->keycode, 1); 75 input_sync(input); 76 } 77 78 button++; 79 } 80 } 81 82 static int __devinit cobalt_buttons_probe(struct platform_device *pdev) 83 { 84 struct buttons_dev *bdev; 85 struct input_polled_dev *poll_dev; 86 struct input_dev *input; 87 struct resource *res; 88 int error, i; 89 90 bdev = kzalloc(sizeof(struct buttons_dev), GFP_KERNEL); 91 poll_dev = input_allocate_polled_device(); 92 if (!bdev || !poll_dev) { 93 error = -ENOMEM; 94 goto err_free_mem; 95 } 96 97 poll_dev->private = bdev; 98 poll_dev->poll = handle_buttons; 99 poll_dev->poll_interval = BUTTONS_POLL_INTERVAL; 100 101 input = poll_dev->input; 102 input->name = "Cobalt buttons"; 103 input->phys = "cobalt/input0"; 104 input->id.bustype = BUS_HOST; 105 input->cdev.dev = &pdev->dev; 106 107 input->evbit[0] = BIT_MASK(EV_KEY); 108 for (i = 0; i < ARRAY_SIZE(buttons_map); i++) { 109 set_bit(buttons_map[i].keycode, input->keybit); 110 buttons_map[i].count = 0; 111 } 112 113 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 114 if (!res) { 115 error = -EBUSY; 116 goto err_free_mem; 117 } 118 119 bdev->poll_dev = poll_dev; 120 bdev->reg = ioremap(res->start, res->end - res->start + 1); 121 dev_set_drvdata(&pdev->dev, bdev); 122 123 error = input_register_polled_device(poll_dev); 124 if (error) 125 goto err_iounmap; 126 127 return 0; 128 129 err_iounmap: 130 iounmap(bdev->reg); 131 err_free_mem: 132 input_free_polled_device(poll_dev); 133 kfree(bdev); 134 dev_set_drvdata(&pdev->dev, NULL); 135 return error; 136 } 137 138 static int __devexit cobalt_buttons_remove(struct platform_device *pdev) 139 { 140 struct device *dev = &pdev->dev; 141 struct buttons_dev *bdev = dev_get_drvdata(dev); 142 143 input_unregister_polled_device(bdev->poll_dev); 144 input_free_polled_device(bdev->poll_dev); 145 iounmap(bdev->reg); 146 kfree(bdev); 147 dev_set_drvdata(dev, NULL); 148 149 return 0; 150 } 151 152 static struct platform_driver cobalt_buttons_driver = { 153 .probe = cobalt_buttons_probe, 154 .remove = __devexit_p(cobalt_buttons_remove), 155 .driver = { 156 .name = "Cobalt buttons", 157 .owner = THIS_MODULE, 158 }, 159 }; 160 161 static int __init cobalt_buttons_init(void) 162 { 163 return platform_driver_register(&cobalt_buttons_driver); 164 } 165 166 static void __exit cobalt_buttons_exit(void) 167 { 168 platform_driver_unregister(&cobalt_buttons_driver); 169 } 170 171 module_init(cobalt_buttons_init); 172 module_exit(cobalt_buttons_exit); 173