1 /* 2 * ON pin driver for Dialog DA9052 PMICs 3 * 4 * Copyright(c) 2012 Dialog Semiconductor Ltd. 5 * 6 * Author: David Dajun Chen <dchen@diasemi.com> 7 * 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms of the GNU General Public License as published by the 10 * Free Software Foundation; either version 2 of the License, or (at your 11 * option) any later version. 12 */ 13 14 #include <linux/input.h> 15 #include <linux/module.h> 16 #include <linux/platform_device.h> 17 #include <linux/workqueue.h> 18 19 #include <linux/mfd/da9052/da9052.h> 20 #include <linux/mfd/da9052/reg.h> 21 22 struct da9052_onkey { 23 struct da9052 *da9052; 24 struct input_dev *input; 25 struct delayed_work work; 26 }; 27 28 static void da9052_onkey_query(struct da9052_onkey *onkey) 29 { 30 int key_stat; 31 32 key_stat = da9052_reg_read(onkey->da9052, DA9052_EVENT_B_REG); 33 if (key_stat < 0) { 34 dev_err(onkey->da9052->dev, 35 "Failed to read onkey event %d\n", key_stat); 36 } else { 37 /* 38 * Since interrupt for deassertion of ONKEY pin is not 39 * generated, onkey event state determines the onkey 40 * button state. 41 */ 42 key_stat &= DA9052_EVENTB_ENONKEY; 43 input_report_key(onkey->input, KEY_POWER, key_stat); 44 input_sync(onkey->input); 45 } 46 47 /* 48 * Interrupt is generated only when the ONKEY pin is asserted. 49 * Hence the deassertion of the pin is simulated through work queue. 50 */ 51 if (key_stat) 52 schedule_delayed_work(&onkey->work, msecs_to_jiffies(50)); 53 } 54 55 static void da9052_onkey_work(struct work_struct *work) 56 { 57 struct da9052_onkey *onkey = container_of(work, struct da9052_onkey, 58 work.work); 59 60 da9052_onkey_query(onkey); 61 } 62 63 static irqreturn_t da9052_onkey_irq(int irq, void *data) 64 { 65 struct da9052_onkey *onkey = data; 66 67 da9052_onkey_query(onkey); 68 69 return IRQ_HANDLED; 70 } 71 72 static int da9052_onkey_probe(struct platform_device *pdev) 73 { 74 struct da9052 *da9052 = dev_get_drvdata(pdev->dev.parent); 75 struct da9052_onkey *onkey; 76 struct input_dev *input_dev; 77 int error; 78 79 if (!da9052) { 80 dev_err(&pdev->dev, "Failed to get the driver's data\n"); 81 return -EINVAL; 82 } 83 84 onkey = kzalloc(sizeof(*onkey), GFP_KERNEL); 85 input_dev = input_allocate_device(); 86 if (!onkey || !input_dev) { 87 dev_err(&pdev->dev, "Failed to allocate memory\n"); 88 error = -ENOMEM; 89 goto err_free_mem; 90 } 91 92 onkey->input = input_dev; 93 onkey->da9052 = da9052; 94 INIT_DELAYED_WORK(&onkey->work, da9052_onkey_work); 95 96 input_dev->name = "da9052-onkey"; 97 input_dev->phys = "da9052-onkey/input0"; 98 input_dev->dev.parent = &pdev->dev; 99 100 input_dev->evbit[0] = BIT_MASK(EV_KEY); 101 __set_bit(KEY_POWER, input_dev->keybit); 102 103 error = da9052_request_irq(onkey->da9052, DA9052_IRQ_NONKEY, "ONKEY", 104 da9052_onkey_irq, onkey); 105 if (error < 0) { 106 dev_err(onkey->da9052->dev, 107 "Failed to register ONKEY IRQ: %d\n", error); 108 goto err_free_mem; 109 } 110 111 error = input_register_device(onkey->input); 112 if (error) { 113 dev_err(&pdev->dev, "Unable to register input device, %d\n", 114 error); 115 goto err_free_irq; 116 } 117 118 platform_set_drvdata(pdev, onkey); 119 return 0; 120 121 err_free_irq: 122 da9052_free_irq(onkey->da9052, DA9052_IRQ_NONKEY, onkey); 123 cancel_delayed_work_sync(&onkey->work); 124 err_free_mem: 125 input_free_device(input_dev); 126 kfree(onkey); 127 128 return error; 129 } 130 131 static int da9052_onkey_remove(struct platform_device *pdev) 132 { 133 struct da9052_onkey *onkey = platform_get_drvdata(pdev); 134 135 da9052_free_irq(onkey->da9052, DA9052_IRQ_NONKEY, onkey); 136 cancel_delayed_work_sync(&onkey->work); 137 138 input_unregister_device(onkey->input); 139 kfree(onkey); 140 141 return 0; 142 } 143 144 static struct platform_driver da9052_onkey_driver = { 145 .probe = da9052_onkey_probe, 146 .remove = da9052_onkey_remove, 147 .driver = { 148 .name = "da9052-onkey", 149 .owner = THIS_MODULE, 150 }, 151 }; 152 module_platform_driver(da9052_onkey_driver); 153 154 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>"); 155 MODULE_DESCRIPTION("Onkey driver for DA9052"); 156 MODULE_LICENSE("GPL"); 157 MODULE_ALIAS("platform:da9052-onkey"); 158