input/misc/da9055_onkey.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  * ON pin driver for Dialog DA9055 PMICs
0004  *
0005  * Copyright(c) 2012 Dialog Semiconductor Ltd.
0006  *
0007  * Author: David Dajun Chen <dchen@diasemi.com>
0008  */
0009
0010 #include <linux/input.h>
0011 #include <linux/module.h>
0012 #include <linux/platform_device.h>
0013
0014 #include <linux/mfd/da9055/core.h>
0015 #include <linux/mfd/da9055/reg.h>
0016
0017 struct da9055_onkey {
0018     struct da9055 *da9055;
0019     struct input_dev *input;
0020     struct delayed_work work;
0021 };
0022
0023 static void da9055_onkey_query(struct da9055_onkey *onkey)
0024 {
0025     int key_stat;
0026
0027     key_stat = da9055_reg_read(onkey->da9055, DA9055_REG_STATUS_A);
0028     if (key_stat < 0) {
0029         dev_err(onkey->da9055->dev,
0030             "Failed to read onkey event %d\n", key_stat);
0031     } else {
0032         key_stat &= DA9055_NOKEY_STS;
0033         /*
0034          * Onkey status bit is cleared when onkey button is released.
0035          */
0036         if (!key_stat) {
0037             input_report_key(onkey->input, KEY_POWER, 0);
0038             input_sync(onkey->input);
0039         }
0040     }
0041
0042     /*
0043      * Interrupt is generated only when the ONKEY pin is asserted.
0044      * Hence the deassertion of the pin is simulated through work queue.
0045      */
0046     if (key_stat)
0047         schedule_delayed_work(&onkey->work, msecs_to_jiffies(10));
0048
0049 }
0050
0051 static void da9055_onkey_work(struct work_struct *work)
0052 {
0053     struct da9055_onkey *onkey = container_of(work, struct da9055_onkey,
0054                           work.work);
0055
0056     da9055_onkey_query(onkey);
0057 }
0058
0059 static irqreturn_t da9055_onkey_irq(int irq, void *data)
0060 {
0061     struct da9055_onkey *onkey = data;
0062
0063     input_report_key(onkey->input, KEY_POWER, 1);
0064     input_sync(onkey->input);
0065
0066     da9055_onkey_query(onkey);
0067
0068     return IRQ_HANDLED;
0069 }
0070
0071 static int da9055_onkey_probe(struct platform_device *pdev)
0072 {
0073     struct da9055 *da9055 = dev_get_drvdata(pdev->dev.parent);
0074     struct da9055_onkey *onkey;
0075     struct input_dev *input_dev;
0076     int irq, err;
0077
0078     irq = platform_get_irq_byname(pdev, "ONKEY");
0079     if (irq < 0)
0080         return -EINVAL;
0081
0082     onkey = devm_kzalloc(&pdev->dev, sizeof(*onkey), GFP_KERNEL);
0083     if (!onkey) {
0084         dev_err(&pdev->dev, "Failed to allocate memory\n");
0085         return -ENOMEM;
0086     }
0087
0088     input_dev = input_allocate_device();
0089     if (!input_dev) {
0090         dev_err(&pdev->dev, "Failed to allocate memory\n");
0091         return -ENOMEM;
0092     }
0093
0094     onkey->input = input_dev;
0095     onkey->da9055 = da9055;
0096     input_dev->name = "da9055-onkey";
0097     input_dev->phys = "da9055-onkey/input0";
0098     input_dev->dev.parent = &pdev->dev;
0099
0100     input_dev->evbit[0] = BIT_MASK(EV_KEY);
0101     __set_bit(KEY_POWER, input_dev->keybit);
0102
0103     INIT_DELAYED_WORK(&onkey->work, da9055_onkey_work);
0104
0105     err = request_threaded_irq(irq, NULL, da9055_onkey_irq,
0106                    IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
0107                    "ONKEY", onkey);
0108     if (err < 0) {
0109         dev_err(&pdev->dev,
0110             "Failed to register ONKEY IRQ %d, error = %d\n",
0111             irq, err);
0112         goto err_free_input;
0113     }
0114
0115     err = input_register_device(input_dev);
0116     if (err) {
0117         dev_err(&pdev->dev, "Unable to register input device, %d\n",
0118             err);
0119         goto err_free_irq;
0120     }
0121
0122     platform_set_drvdata(pdev, onkey);
0123
0124     return 0;
0125
0126 err_free_irq:
0127     free_irq(irq, onkey);
0128     cancel_delayed_work_sync(&onkey->work);
0129 err_free_input:
0130     input_free_device(input_dev);
0131
0132     return err;
0133 }
0134
0135 static int da9055_onkey_remove(struct platform_device *pdev)
0136 {
0137     struct da9055_onkey *onkey = platform_get_drvdata(pdev);
0138     int irq = platform_get_irq_byname(pdev, "ONKEY");
0139
0140     irq = regmap_irq_get_virq(onkey->da9055->irq_data, irq);
0141     free_irq(irq, onkey);
0142     cancel_delayed_work_sync(&onkey->work);
0143     input_unregister_device(onkey->input);
0144
0145     return 0;
0146 }
0147
0148 static struct platform_driver da9055_onkey_driver = {
0149     .probe  = da9055_onkey_probe,
0150     .remove = da9055_onkey_remove,
0151     .driver = {
0152         .name   = "da9055-onkey",
0153     },
0154 };
0155
0156 module_platform_driver(da9055_onkey_driver);
0157
0158 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
0159 MODULE_DESCRIPTION("Onkey driver for DA9055");
0160 MODULE_LICENSE("GPL");
0161 MODULE_ALIAS("platform:da9055-onkey");