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