drivers/input/misc/sirfsoc-onkey.c

   1 /*
   2  * Power key driver for SiRF PrimaII
   3  *
   4  * Copyright (c) 2013 Cambridge Silicon Radio Limited, a CSR plc group company.
   5  *
   6  * Licensed under GPLv2 or later.
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/interrupt.h>
  11 #include <linux/delay.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/input.h>
  14 #include <linux/rtc/sirfsoc_rtciobrg.h>
  15 #include <linux/of.h>
  16
  17 struct sirfsoc_pwrc_drvdata {
  18         u32                     pwrc_base;
  19         struct input_dev        *input;
  20 };
  21
  22 #define PWRC_ON_KEY_BIT                 (1 << 0)
  23
  24 #define PWRC_INT_STATUS                 0xc
  25 #define PWRC_INT_MASK                   0x10
  26
  27 static irqreturn_t sirfsoc_pwrc_isr(int irq, void *dev_id)
  28 {
  29         struct sirfsoc_pwrc_drvdata *pwrcdrv = dev_id;
  30         u32 int_status;
  31
  32         int_status = sirfsoc_rtc_iobrg_readl(pwrcdrv->pwrc_base +
  33                                                         PWRC_INT_STATUS);
  34         sirfsoc_rtc_iobrg_writel(int_status & ~PWRC_ON_KEY_BIT,
  35                                  pwrcdrv->pwrc_base + PWRC_INT_STATUS);
  36
  37         /*
  38          * For a typical Linux system, we report KEY_SUSPEND to trigger apm-power.c
  39          * to queue a SUSPEND APM event
  40          */
  41         input_event(pwrcdrv->input, EV_PWR, KEY_SUSPEND, 1);
  42         input_sync(pwrcdrv->input);
  43
  44         /*
  45          * Todo: report KEY_POWER event for Android platforms, Android PowerManager
  46          * will handle the suspend and powerdown/hibernation
  47          */
  48
  49         return IRQ_HANDLED;
  50 }
  51
  52 static const struct of_device_id sirfsoc_pwrc_of_match[] = {
  53         { .compatible = "sirf,prima2-pwrc" },
  54         {},
  55 }
  56 MODULE_DEVICE_TABLE(of, sirfsoc_pwrc_of_match);
  57
  58 static int sirfsoc_pwrc_probe(struct platform_device *pdev)
  59 {
  60         struct device_node *np = pdev->dev.of_node;
  61         struct sirfsoc_pwrc_drvdata *pwrcdrv;
  62         int irq;
  63         int error;
  64
  65         pwrcdrv = devm_kzalloc(&pdev->dev, sizeof(struct sirfsoc_pwrc_drvdata),
  66                                GFP_KERNEL);
  67         if (!pwrcdrv) {
  68                 dev_info(&pdev->dev, "Not enough memory for the device data\n");
  69                 return -ENOMEM;
  70         }
  71
  72         /*
  73          * we can't use of_iomap because pwrc is not mapped in memory,
  74          * the so-called base address is only offset in rtciobrg
  75          */
  76         error = of_property_read_u32(np, "reg", &pwrcdrv->pwrc_base);
  77         if (error) {
  78                 dev_err(&pdev->dev,
  79                         "unable to find base address of pwrc node in dtb\n");
  80                 return error;
  81         }
  82
  83         pwrcdrv->input = devm_input_allocate_device(&pdev->dev);
  84         if (!pwrcdrv->input)
  85                 return -ENOMEM;
  86
  87         pwrcdrv->input->name = "sirfsoc pwrckey";
  88         pwrcdrv->input->phys = "pwrc/input0";
  89         pwrcdrv->input->evbit[0] = BIT_MASK(EV_PWR);
  90
  91         irq = platform_get_irq(pdev, 0);
  92         error = devm_request_irq(&pdev->dev, irq,
  93                                  sirfsoc_pwrc_isr, IRQF_SHARED,
  94                                  "sirfsoc_pwrc_int", pwrcdrv);
  95         if (error) {
  96                 dev_err(&pdev->dev, "unable to claim irq %d, error: %d\n",
  97                         irq, error);
  98                 return error;
  99         }
 100
 101         sirfsoc_rtc_iobrg_writel(
 102                 sirfsoc_rtc_iobrg_readl(pwrcdrv->pwrc_base + PWRC_INT_MASK) |
 103                         PWRC_ON_KEY_BIT,
 104                 pwrcdrv->pwrc_base + PWRC_INT_MASK);
 105
 106         error = input_register_device(pwrcdrv->input);
 107         if (error) {
 108                 dev_err(&pdev->dev,
 109                         "unable to register input device, error: %d\n",
 110                         error);
 111                 return error;
 112         }
 113
 114         platform_set_drvdata(pdev, pwrcdrv);
 115         device_init_wakeup(&pdev->dev, 1);
 116
 117         return 0;
 118 }
 119
 120 static int sirfsoc_pwrc_remove(struct platform_device *pdev)
 121 {
 122         device_init_wakeup(&pdev->dev, 0);
 123
 124         return 0;
 125 }
 126
 127 #ifdef CONFIG_PM_SLEEP
 128 static int pwrc_resume(struct device *dev)
 129 {
 130         struct platform_device *pdev = to_platform_device(dev);
 131         struct sirfsoc_pwrc_drvdata *pwrcdrv = platform_get_drvdata(pdev);
 132
 133         /*
 134          * Do not mask pwrc interrupt as we want pwrc work as a wakeup source
 135          * if users touch X_ONKEY_B, see arch/arm/mach-prima2/pm.c
 136          */
 137         sirfsoc_rtc_iobrg_writel(
 138                 sirfsoc_rtc_iobrg_readl(
 139                 pwrcdrv->pwrc_base + PWRC_INT_MASK) | PWRC_ON_KEY_BIT,
 140                 pwrcdrv->pwrc_base + PWRC_INT_MASK);
 141
 142         return 0;
 143 }
 144 #endif
 145
 146 static SIMPLE_DEV_PM_OPS(sirfsoc_pwrc_pm_ops, NULL, pwrc_resume);
 147
 148 static struct platform_driver sirfsoc_pwrc_driver = {
 149         .probe          = sirfsoc_pwrc_probe,
 150         .remove         = sirfsoc_pwrc_remove,
 151         .driver         = {
 152                 .name   = "sirfsoc-pwrc",
 153                 .owner  = THIS_MODULE,
 154                 .pm     = &sirfsoc_pwrc_pm_ops,
 155                 .of_match_table = sirfsoc_pwrc_of_match,
 156         }
 157 };
 158
 159 module_platform_driver(sirfsoc_pwrc_driver);
 160
 161 MODULE_LICENSE("GPLv2");
 162 MODULE_AUTHOR("Binghua Duan <Binghua.Duan@csr.com>, Xianglong Du <Xianglong.Du@csr.com>");
 163 MODULE_DESCRIPTION("CSR Prima2 PWRC Driver");
 164 MODULE_ALIAS("platform:sirfsoc-pwrc");