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/init.h> 15 #include <linux/input.h> 16 #include <linux/module.h> 17 #include <linux/platform_device.h> 18 #include <linux/workqueue.h> 19 20 #include <linux/mfd/da9052/da9052.h> 21 #include <linux/mfd/da9052/reg.h> 22 23 struct da9052_onkey { 24 struct da9052 *da9052; 25 struct input_dev *input; 26 struct delayed_work work; 27 }; 28 29 static void da9052_onkey_query(struct da9052_onkey *onkey) 30 { 31 int key_stat; 32 33 key_stat = da9052_reg_read(onkey->da9052, DA9052_EVENT_B_REG); 34 if (key_stat < 0) { 35 dev_err(onkey->da9052->dev, 36 "Failed to read onkey event %d\n", key_stat); 37 } else { 38 /* 39 * Since interrupt for deassertion of ONKEY pin is not 40 * generated, onkey event state determines the onkey 41 * button state. 42 */ 43 key_stat &= DA9052_EVENTB_ENONKEY; 44 input_report_key(onkey->input, KEY_POWER, key_stat); 45 input_sync(onkey->input); 46 } 47 48 /* 49 * Interrupt is generated only when the ONKEY pin is asserted. 50 * Hence the deassertion of the pin is simulated through work queue. 51 */ 52 if (key_stat) 53 schedule_delayed_work(&onkey->work, msecs_to_jiffies(50)); 54 } 55 56 static void da9052_onkey_work(struct work_struct *work) 57 { 58 struct da9052_onkey *onkey = container_of(work, struct da9052_onkey, 59 work.work); 60 61 da9052_onkey_query(onkey); 62 } 63 64 static irqreturn_t da9052_onkey_irq(int irq, void *data) 65 { 66 struct da9052_onkey *onkey = data; 67 68 da9052_onkey_query(onkey); 69 70 return IRQ_HANDLED; 71 } 72 73 static int da9052_onkey_probe(struct platform_device *pdev) 74 { 75 struct da9052 *da9052 = dev_get_drvdata(pdev->dev.parent); 76 struct da9052_onkey *onkey; 77 struct input_dev *input_dev; 78 int error; 79 80 if (!da9052) { 81 dev_err(&pdev->dev, "Failed to get the driver's data\n"); 82 return -EINVAL; 83 } 84 85 onkey = kzalloc(sizeof(*onkey), GFP_KERNEL); 86 input_dev = input_allocate_device(); 87 if (!onkey || !input_dev) { 88 dev_err(&pdev->dev, "Failed to allocate memory\n"); 89 error = -ENOMEM; 90 goto err_free_mem; 91 } 92 93 onkey->input = input_dev; 94 onkey->da9052 = da9052; 95 INIT_DELAYED_WORK(&onkey->work, da9052_onkey_work); 96 97 input_dev->name = "da9052-onkey"; 98 input_dev->phys = "da9052-onkey/input0"; 99 input_dev->dev.parent = &pdev->dev; 100 101 input_dev->evbit[0] = BIT_MASK(EV_KEY); 102 __set_bit(KEY_POWER, input_dev->keybit); 103 104 error = da9052_request_irq(onkey->da9052, DA9052_IRQ_NONKEY, "ONKEY", 105 da9052_onkey_irq, onkey); 106 if (error < 0) { 107 dev_err(onkey->da9052->dev, 108 "Failed to register ONKEY IRQ: %d\n", error); 109 goto err_free_mem; 110 } 111 112 error = input_register_device(onkey->input); 113 if (error) { 114 dev_err(&pdev->dev, "Unable to register input device, %d\n", 115 error); 116 goto err_free_irq; 117 } 118 119 platform_set_drvdata(pdev, onkey); 120 return 0; 121 122 err_free_irq: 123 da9052_free_irq(onkey->da9052, DA9052_IRQ_NONKEY, onkey); 124 cancel_delayed_work_sync(&onkey->work); 125 err_free_mem: 126 input_free_device(input_dev); 127 kfree(onkey); 128 129 return error; 130 } 131 132 static int da9052_onkey_remove(struct platform_device *pdev) 133 { 134 struct da9052_onkey *onkey = platform_get_drvdata(pdev); 135 136 da9052_free_irq(onkey->da9052, DA9052_IRQ_NONKEY, onkey); 137 cancel_delayed_work_sync(&onkey->work); 138 139 input_unregister_device(onkey->input); 140 kfree(onkey); 141 142 return 0; 143 } 144 145 static struct platform_driver da9052_onkey_driver = { 146 .probe = da9052_onkey_probe, 147 .remove = da9052_onkey_remove, 148 .driver = { 149 .name = "da9052-onkey", 150 .owner = THIS_MODULE, 151 }, 152 }; 153 module_platform_driver(da9052_onkey_driver); 154 155 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>"); 156 MODULE_DESCRIPTION("Onkey driver for DA9052"); 157 MODULE_LICENSE("GPL"); 158 MODULE_ALIAS("platform:da9052-onkey"); 159