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.h> 22 #include <linux/ioport.h> 23 #include <linux/module.h> 24 #include <linux/platform_device.h> 25 #include <linux/jiffies.h> 26 #include <linux/timer.h> 27 28 #define BUTTONS_POLL_INTERVAL 30 /* msec */ 29 #define BUTTONS_COUNT_THRESHOLD 3 30 #define BUTTONS_STATUS_MASK 0xfe000000 31 32 struct buttons_dev { 33 struct input_dev *input; 34 void __iomem *reg; 35 }; 36 37 struct buttons_map { 38 uint32_t mask; 39 int keycode; 40 int count; 41 }; 42 43 static struct buttons_map buttons_map[] = { 44 { 0x02000000, KEY_RESTART, }, 45 { 0x04000000, KEY_LEFT, }, 46 { 0x08000000, KEY_UP, }, 47 { 0x10000000, KEY_DOWN, }, 48 { 0x20000000, KEY_RIGHT, }, 49 { 0x40000000, KEY_ENTER, }, 50 { 0x80000000, KEY_SELECT, }, 51 }; 52 53 static struct timer_list buttons_timer; 54 55 static void handle_buttons(unsigned long data) 56 { 57 struct buttons_map *button = buttons_map; 58 struct buttons_dev *bdev; 59 uint32_t status; 60 int i; 61 62 bdev = (struct buttons_dev *)data; 63 status = readl(bdev->reg); 64 status = ~status & BUTTONS_STATUS_MASK; 65 66 for (i = 0; i < ARRAY_SIZE(buttons_map); i++) { 67 if (status & button->mask) { 68 button->count++; 69 } else { 70 if (button->count >= BUTTONS_COUNT_THRESHOLD) { 71 input_report_key(bdev->input, button->keycode, 0); 72 input_sync(bdev->input); 73 } 74 button->count = 0; 75 } 76 77 if (button->count == BUTTONS_COUNT_THRESHOLD) { 78 input_report_key(bdev->input, button->keycode, 1); 79 input_sync(bdev->input); 80 } 81 82 button++; 83 } 84 85 mod_timer(&buttons_timer, jiffies + msecs_to_jiffies(BUTTONS_POLL_INTERVAL)); 86 } 87 88 static int cobalt_buttons_open(struct input_dev *dev) 89 { 90 mod_timer(&buttons_timer, jiffies + msecs_to_jiffies(BUTTONS_POLL_INTERVAL)); 91 92 return 0; 93 } 94 95 static void cobalt_buttons_close(struct input_dev *dev) 96 { 97 del_timer_sync(&buttons_timer); 98 } 99 100 static int __devinit cobalt_buttons_probe(struct platform_device *pdev) 101 { 102 struct buttons_dev *bdev; 103 struct input_dev *input; 104 struct resource *res; 105 int error, i; 106 107 bdev = kzalloc(sizeof(struct buttons_dev), GFP_KERNEL); 108 input = input_allocate_device(); 109 if (!bdev || !input) { 110 error = -ENOMEM; 111 goto err_free_mem; 112 } 113 114 input->name = "Cobalt buttons"; 115 input->phys = "cobalt/input0"; 116 input->id.bustype = BUS_HOST; 117 input->cdev.dev = &pdev->dev; 118 input->open = cobalt_buttons_open; 119 input->close = cobalt_buttons_close; 120 121 input->evbit[0] = BIT(EV_KEY); 122 for (i = 0; i < ARRAY_SIZE(buttons_map); i++) { 123 set_bit(buttons_map[i].keycode, input->keybit); 124 buttons_map[i].count = 0; 125 } 126 127 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 128 if (!res) { 129 error = -EBUSY; 130 goto err_free_mem; 131 } 132 133 bdev->input = input; 134 bdev->reg = ioremap(res->start, res->end - res->start + 1); 135 dev_set_drvdata(&pdev->dev, bdev); 136 137 setup_timer(&buttons_timer, handle_buttons, (unsigned long)bdev); 138 139 error = input_register_device(input); 140 if (error) 141 goto err_iounmap; 142 143 return 0; 144 145 err_iounmap: 146 iounmap(bdev->reg); 147 err_free_mem: 148 input_free_device(input); 149 kfree(bdev); 150 dev_set_drvdata(&pdev->dev, NULL); 151 return error; 152 } 153 154 static int __devexit cobalt_buttons_remove(struct platform_device *pdev) 155 { 156 struct device *dev = &pdev->dev; 157 struct buttons_dev *bdev = dev_get_drvdata(dev); 158 159 input_unregister_device(bdev->input); 160 iounmap(bdev->reg); 161 kfree(bdev); 162 dev_set_drvdata(dev, NULL); 163 164 return 0; 165 } 166 167 static struct platform_driver cobalt_buttons_driver = { 168 .probe = cobalt_buttons_probe, 169 .remove = __devexit_p(cobalt_buttons_remove), 170 .driver = { 171 .name = "Cobalt buttons", 172 .owner = THIS_MODULE, 173 }, 174 }; 175 176 static int __init cobalt_buttons_init(void) 177 { 178 return platform_driver_register(&cobalt_buttons_driver); 179 } 180 181 static void __exit cobalt_buttons_exit(void) 182 { 183 platform_driver_unregister(&cobalt_buttons_driver); 184 } 185 186 module_init(cobalt_buttons_init); 187 module_exit(cobalt_buttons_exit); 188