input/misc/pcap_keys.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  *  Input driver for PCAP events:
0004  *   * Power key
0005  *   * Headphone button
0006  *
0007  *  Copyright (c) 2008,2009 Ilya Petrov <ilya.muromec@gmail.com>
0008  */
0009
0010 #include <linux/module.h>
0011 #include <linux/interrupt.h>
0012 #include <linux/platform_device.h>
0013 #include <linux/input.h>
0014 #include <linux/mfd/ezx-pcap.h>
0015 #include <linux/slab.h>
0016
0017 struct pcap_keys {
0018     struct pcap_chip *pcap;
0019     struct input_dev *input;
0020 };
0021
0022 /* PCAP2 interrupts us on keypress */
0023 static irqreturn_t pcap_keys_handler(int irq, void *_pcap_keys)
0024 {
0025     struct pcap_keys *pcap_keys = _pcap_keys;
0026     int pirq = irq_to_pcap(pcap_keys->pcap, irq);
0027     u32 pstat;
0028
0029     ezx_pcap_read(pcap_keys->pcap, PCAP_REG_PSTAT, &pstat);
0030     pstat &= 1 << pirq;
0031
0032     switch (pirq) {
0033     case PCAP_IRQ_ONOFF:
0034         input_report_key(pcap_keys->input, KEY_POWER, !pstat);
0035         break;
0036     case PCAP_IRQ_MIC:
0037         input_report_key(pcap_keys->input, KEY_HP, !pstat);
0038         break;
0039     }
0040
0041     input_sync(pcap_keys->input);
0042
0043     return IRQ_HANDLED;
0044 }
0045
0046 static int pcap_keys_probe(struct platform_device *pdev)
0047 {
0048     int err = -ENOMEM;
0049     struct pcap_keys *pcap_keys;
0050     struct input_dev *input_dev;
0051
0052     pcap_keys = kmalloc(sizeof(struct pcap_keys), GFP_KERNEL);
0053     if (!pcap_keys)
0054         return err;
0055
0056     pcap_keys->pcap = dev_get_drvdata(pdev->dev.parent);
0057
0058     input_dev = input_allocate_device();
0059     if (!input_dev)
0060         goto fail;
0061
0062     pcap_keys->input = input_dev;
0063
0064     platform_set_drvdata(pdev, pcap_keys);
0065     input_dev->name = pdev->name;
0066     input_dev->phys = "pcap-keys/input0";
0067     input_dev->id.bustype = BUS_HOST;
0068     input_dev->dev.parent = &pdev->dev;
0069
0070     __set_bit(EV_KEY, input_dev->evbit);
0071     __set_bit(KEY_POWER, input_dev->keybit);
0072     __set_bit(KEY_HP, input_dev->keybit);
0073
0074     err = input_register_device(input_dev);
0075     if (err)
0076         goto fail_allocate;
0077
0078     err = request_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF),
0079             pcap_keys_handler, 0, "Power key", pcap_keys);
0080     if (err)
0081         goto fail_register;
0082
0083     err = request_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_MIC),
0084             pcap_keys_handler, 0, "Headphone button", pcap_keys);
0085     if (err)
0086         goto fail_pwrkey;
0087
0088     return 0;
0089
0090 fail_pwrkey:
0091     free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF), pcap_keys);
0092 fail_register:
0093     input_unregister_device(input_dev);
0094     goto fail;
0095 fail_allocate:
0096     input_free_device(input_dev);
0097 fail:
0098     kfree(pcap_keys);
0099     return err;
0100 }
0101
0102 static int pcap_keys_remove(struct platform_device *pdev)
0103 {
0104     struct pcap_keys *pcap_keys = platform_get_drvdata(pdev);
0105
0106     free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF), pcap_keys);
0107     free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_MIC), pcap_keys);
0108
0109     input_unregister_device(pcap_keys->input);
0110     kfree(pcap_keys);
0111
0112     return 0;
0113 }
0114
0115 static struct platform_driver pcap_keys_device_driver = {
0116     .probe      = pcap_keys_probe,
0117     .remove     = pcap_keys_remove,
0118     .driver     = {
0119         .name   = "pcap-keys",
0120     }
0121 };
0122 module_platform_driver(pcap_keys_device_driver);
0123
0124 MODULE_DESCRIPTION("Motorola PCAP2 input events driver");
0125 MODULE_AUTHOR("Ilya Petrov <ilya.muromec@gmail.com>");
0126 MODULE_LICENSE("GPL");
0127 MODULE_ALIAS("platform:pcap_keys");