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-polldev.h> 8 #include <linux/ioport.h> 9 #include <linux/module.h> 10 #include <linux/platform_device.h> 11 #include <linux/slab.h> 12 13 #define BUTTONS_POLL_INTERVAL 30 /* msec */ 14 #define BUTTONS_COUNT_THRESHOLD 3 15 #define BUTTONS_STATUS_MASK 0xfe000000 16 17 static const unsigned short cobalt_map[] = { 18 KEY_RESERVED, 19 KEY_RESTART, 20 KEY_LEFT, 21 KEY_UP, 22 KEY_DOWN, 23 KEY_RIGHT, 24 KEY_ENTER, 25 KEY_SELECT 26 }; 27 28 struct buttons_dev { 29 struct input_polled_dev *poll_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_polled_dev *dev) 36 { 37 struct buttons_dev *bdev = dev->private; 38 struct input_dev *input = dev->input; 39 uint32_t status; 40 int i; 41 42 status = ~readl(bdev->reg) >> 24; 43 44 for (i = 0; i < ARRAY_SIZE(bdev->keymap); i++) { 45 if (status & (1U << i)) { 46 if (++bdev->count[i] == BUTTONS_COUNT_THRESHOLD) { 47 input_event(input, EV_MSC, MSC_SCAN, i); 48 input_report_key(input, bdev->keymap[i], 1); 49 input_sync(input); 50 } 51 } else { 52 if (bdev->count[i] >= BUTTONS_COUNT_THRESHOLD) { 53 input_event(input, EV_MSC, MSC_SCAN, i); 54 input_report_key(input, bdev->keymap[i], 0); 55 input_sync(input); 56 } 57 bdev->count[i] = 0; 58 } 59 } 60 } 61 62 static int cobalt_buttons_probe(struct platform_device *pdev) 63 { 64 struct buttons_dev *bdev; 65 struct input_polled_dev *poll_dev; 66 struct input_dev *input; 67 struct resource *res; 68 int error, i; 69 70 bdev = kzalloc(sizeof(struct buttons_dev), GFP_KERNEL); 71 poll_dev = input_allocate_polled_device(); 72 if (!bdev || !poll_dev) { 73 error = -ENOMEM; 74 goto err_free_mem; 75 } 76 77 memcpy(bdev->keymap, cobalt_map, sizeof(bdev->keymap)); 78 79 poll_dev->private = bdev; 80 poll_dev->poll = handle_buttons; 81 poll_dev->poll_interval = BUTTONS_POLL_INTERVAL; 82 83 input = poll_dev->input; 84 input->name = "Cobalt buttons"; 85 input->phys = "cobalt/input0"; 86 input->id.bustype = BUS_HOST; 87 input->dev.parent = &pdev->dev; 88 89 input->keycode = bdev->keymap; 90 input->keycodemax = ARRAY_SIZE(bdev->keymap); 91 input->keycodesize = sizeof(unsigned short); 92 93 input_set_capability(input, EV_MSC, MSC_SCAN); 94 __set_bit(EV_KEY, input->evbit); 95 for (i = 0; i < ARRAY_SIZE(cobalt_map); i++) 96 __set_bit(bdev->keymap[i], input->keybit); 97 __clear_bit(KEY_RESERVED, input->keybit); 98 99 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 100 if (!res) { 101 error = -EBUSY; 102 goto err_free_mem; 103 } 104 105 bdev->poll_dev = poll_dev; 106 bdev->reg = ioremap(res->start, resource_size(res)); 107 dev_set_drvdata(&pdev->dev, bdev); 108 109 error = input_register_polled_device(poll_dev); 110 if (error) 111 goto err_iounmap; 112 113 return 0; 114 115 err_iounmap: 116 iounmap(bdev->reg); 117 err_free_mem: 118 input_free_polled_device(poll_dev); 119 kfree(bdev); 120 return error; 121 } 122 123 static int cobalt_buttons_remove(struct platform_device *pdev) 124 { 125 struct device *dev = &pdev->dev; 126 struct buttons_dev *bdev = dev_get_drvdata(dev); 127 128 input_unregister_polled_device(bdev->poll_dev); 129 input_free_polled_device(bdev->poll_dev); 130 iounmap(bdev->reg); 131 kfree(bdev); 132 133 return 0; 134 } 135 136 MODULE_AUTHOR("Yoichi Yuasa <yuasa@linux-mips.org>"); 137 MODULE_DESCRIPTION("Cobalt button interface driver"); 138 MODULE_LICENSE("GPL"); 139 /* work with hotplug and coldplug */ 140 MODULE_ALIAS("platform:Cobalt buttons"); 141 142 static struct platform_driver cobalt_buttons_driver = { 143 .probe = cobalt_buttons_probe, 144 .remove = cobalt_buttons_remove, 145 .driver = { 146 .name = "Cobalt buttons", 147 }, 148 }; 149 module_platform_driver(cobalt_buttons_driver); 150