1 /* 2 * SGI Volume Button interface driver 3 * 4 * Copyright (C) 2008 Thomas Bogendoerfer <tsbogend@alpha.franken.de> 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 #include <linux/slab.h> 26 27 #ifdef CONFIG_SGI_IP22 28 #include <asm/sgi/ioc.h> 29 30 static inline u8 button_status(void) 31 { 32 u8 status; 33 34 status = readb(&sgioc->panel) ^ 0xa0; 35 return ((status & 0x80) >> 6) | ((status & 0x20) >> 5); 36 } 37 #endif 38 39 #ifdef CONFIG_SGI_IP32 40 #include <asm/ip32/mace.h> 41 42 static inline u8 button_status(void) 43 { 44 u64 status; 45 46 status = readq(&mace->perif.audio.control); 47 writeq(status & ~(3U << 23), &mace->perif.audio.control); 48 49 return (status >> 23) & 3; 50 } 51 #endif 52 53 #define BUTTONS_POLL_INTERVAL 30 /* msec */ 54 #define BUTTONS_COUNT_THRESHOLD 3 55 56 static const unsigned short sgi_map[] = { 57 KEY_VOLUMEDOWN, 58 KEY_VOLUMEUP 59 }; 60 61 struct buttons_dev { 62 struct input_polled_dev *poll_dev; 63 unsigned short keymap[ARRAY_SIZE(sgi_map)]; 64 int count[ARRAY_SIZE(sgi_map)]; 65 }; 66 67 static void handle_buttons(struct input_polled_dev *dev) 68 { 69 struct buttons_dev *bdev = dev->private; 70 struct input_dev *input = dev->input; 71 u8 status; 72 int i; 73 74 status = button_status(); 75 76 for (i = 0; i < ARRAY_SIZE(bdev->keymap); i++) { 77 if (status & (1U << i)) { 78 if (++bdev->count[i] == BUTTONS_COUNT_THRESHOLD) { 79 input_event(input, EV_MSC, MSC_SCAN, i); 80 input_report_key(input, bdev->keymap[i], 1); 81 input_sync(input); 82 } 83 } else { 84 if (bdev->count[i] >= BUTTONS_COUNT_THRESHOLD) { 85 input_event(input, EV_MSC, MSC_SCAN, i); 86 input_report_key(input, bdev->keymap[i], 0); 87 input_sync(input); 88 } 89 bdev->count[i] = 0; 90 } 91 } 92 } 93 94 static int sgi_buttons_probe(struct platform_device *pdev) 95 { 96 struct buttons_dev *bdev; 97 struct input_polled_dev *poll_dev; 98 struct input_dev *input; 99 int error, i; 100 101 bdev = kzalloc(sizeof(struct buttons_dev), GFP_KERNEL); 102 poll_dev = input_allocate_polled_device(); 103 if (!bdev || !poll_dev) { 104 error = -ENOMEM; 105 goto err_free_mem; 106 } 107 108 memcpy(bdev->keymap, sgi_map, sizeof(bdev->keymap)); 109 110 poll_dev->private = bdev; 111 poll_dev->poll = handle_buttons; 112 poll_dev->poll_interval = BUTTONS_POLL_INTERVAL; 113 114 input = poll_dev->input; 115 input->name = "SGI buttons"; 116 input->phys = "sgi/input0"; 117 input->id.bustype = BUS_HOST; 118 input->dev.parent = &pdev->dev; 119 120 input->keycode = bdev->keymap; 121 input->keycodemax = ARRAY_SIZE(bdev->keymap); 122 input->keycodesize = sizeof(unsigned short); 123 124 input_set_capability(input, EV_MSC, MSC_SCAN); 125 __set_bit(EV_KEY, input->evbit); 126 for (i = 0; i < ARRAY_SIZE(sgi_map); i++) 127 __set_bit(bdev->keymap[i], input->keybit); 128 __clear_bit(KEY_RESERVED, input->keybit); 129 130 bdev->poll_dev = poll_dev; 131 platform_set_drvdata(pdev, bdev); 132 133 error = input_register_polled_device(poll_dev); 134 if (error) 135 goto err_free_mem; 136 137 return 0; 138 139 err_free_mem: 140 input_free_polled_device(poll_dev); 141 kfree(bdev); 142 return error; 143 } 144 145 static int sgi_buttons_remove(struct platform_device *pdev) 146 { 147 struct buttons_dev *bdev = platform_get_drvdata(pdev); 148 149 input_unregister_polled_device(bdev->poll_dev); 150 input_free_polled_device(bdev->poll_dev); 151 kfree(bdev); 152 153 return 0; 154 } 155 156 static struct platform_driver sgi_buttons_driver = { 157 .probe = sgi_buttons_probe, 158 .remove = sgi_buttons_remove, 159 .driver = { 160 .name = "sgibtns", 161 .owner = THIS_MODULE, 162 }, 163 }; 164 module_platform_driver(sgi_buttons_driver); 165 166 MODULE_LICENSE("GPL"); 167