1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Cobalt button interface driver. 4 * 5 * Copyright (C) 2007-2008 Yoichi Yuasa <yuasa@linux-mips.org> 6 */ 7 #include <linux/input.h> 8 #include <linux/io.h> 9 #include <linux/ioport.h> 10 #include <linux/module.h> 11 #include <linux/platform_device.h> 12 #include <linux/slab.h> 13 14 #define BUTTONS_POLL_INTERVAL 30 /* msec */ 15 #define BUTTONS_COUNT_THRESHOLD 3 16 #define BUTTONS_STATUS_MASK 0xfe000000 17 18 static const unsigned short cobalt_map[] = { 19 KEY_RESERVED, 20 KEY_RESTART, 21 KEY_LEFT, 22 KEY_UP, 23 KEY_DOWN, 24 KEY_RIGHT, 25 KEY_ENTER, 26 KEY_SELECT 27 }; 28 29 struct buttons_dev { 30 unsigned short keymap[ARRAY_SIZE(cobalt_map)]; 31 int count[ARRAY_SIZE(cobalt_map)]; 32 void __iomem *reg; 33 }; 34 35 static void handle_buttons(struct input_dev *input) 36 { 37 struct buttons_dev *bdev = input_get_drvdata(input); 38 uint32_t status; 39 int i; 40 41 status = ~readl(bdev->reg) >> 24; 42 43 for (i = 0; i < ARRAY_SIZE(bdev->keymap); i++) { 44 if (status & (1U << i)) { 45 if (++bdev->count[i] == BUTTONS_COUNT_THRESHOLD) { 46 input_event(input, EV_MSC, MSC_SCAN, i); 47 input_report_key(input, bdev->keymap[i], 1); 48 input_sync(input); 49 } 50 } else { 51 if (bdev->count[i] >= BUTTONS_COUNT_THRESHOLD) { 52 input_event(input, EV_MSC, MSC_SCAN, i); 53 input_report_key(input, bdev->keymap[i], 0); 54 input_sync(input); 55 } 56 bdev->count[i] = 0; 57 } 58 } 59 } 60 61 static int cobalt_buttons_probe(struct platform_device *pdev) 62 { 63 struct buttons_dev *bdev; 64 struct input_dev *input; 65 struct resource *res; 66 int error, i; 67 68 bdev = devm_kzalloc(&pdev->dev, sizeof(*bdev), GFP_KERNEL); 69 if (!bdev) 70 return -ENOMEM; 71 72 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 73 if (!res) 74 return -EBUSY; 75 76 bdev->reg = devm_ioremap(&pdev->dev, res->start, resource_size(res)); 77 if (!bdev->reg) 78 return -ENOMEM; 79 80 memcpy(bdev->keymap, cobalt_map, sizeof(bdev->keymap)); 81 82 input = devm_input_allocate_device(&pdev->dev); 83 if (!input) 84 return -ENOMEM; 85 86 input_set_drvdata(input, bdev); 87 88 input->name = "Cobalt buttons"; 89 input->phys = "cobalt/input0"; 90 input->id.bustype = BUS_HOST; 91 92 input->keycode = bdev->keymap; 93 input->keycodemax = ARRAY_SIZE(bdev->keymap); 94 input->keycodesize = sizeof(unsigned short); 95 96 input_set_capability(input, EV_MSC, MSC_SCAN); 97 __set_bit(EV_KEY, input->evbit); 98 for (i = 0; i < ARRAY_SIZE(cobalt_map); i++) 99 __set_bit(bdev->keymap[i], input->keybit); 100 __clear_bit(KEY_RESERVED, input->keybit); 101 102 103 error = input_setup_polling(input, handle_buttons); 104 if (error) 105 return error; 106 107 input_set_poll_interval(input, BUTTONS_POLL_INTERVAL); 108 109 error = input_register_device(input); 110 if (error) 111 return error; 112 113 return 0; 114 } 115 116 MODULE_AUTHOR("Yoichi Yuasa <yuasa@linux-mips.org>"); 117 MODULE_DESCRIPTION("Cobalt button interface driver"); 118 MODULE_LICENSE("GPL"); 119 /* work with hotplug and coldplug */ 120 MODULE_ALIAS("platform:Cobalt buttons"); 121 122 static struct platform_driver cobalt_buttons_driver = { 123 .probe = cobalt_buttons_probe, 124 .driver = { 125 .name = "Cobalt buttons", 126 }, 127 }; 128 module_platform_driver(cobalt_buttons_driver); 129