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 void sirfsoc_pwrc_toggle_interrupts(struct sirfsoc_pwrc_drvdata *pwrcdrv,
  53                                            bool enable)
  54 {
  55         u32 int_mask;
  56
  57         int_mask = sirfsoc_rtc_iobrg_readl(pwrcdrv->pwrc_base + PWRC_INT_MASK);
  58         if (enable)
  59                 int_mask |= PWRC_ON_KEY_BIT;
  60         else
  61                 int_mask &= ~PWRC_ON_KEY_BIT;
  62         sirfsoc_rtc_iobrg_writel(int_mask, pwrcdrv->pwrc_base + PWRC_INT_MASK);
  63 }
  64
  65 static int sirfsoc_pwrc_open(struct input_dev *input)
  66 {
  67         struct sirfsoc_pwrc_drvdata *pwrcdrv = input_get_drvdata(input);
  68
  69         sirfsoc_pwrc_toggle_interrupts(pwrcdrv, true);
  70
  71         return 0;
  72 }
  73
  74 static void sirfsoc_pwrc_close(struct input_dev *input)
  75 {
  76         struct sirfsoc_pwrc_drvdata *pwrcdrv = input_get_drvdata(input);
  77
  78         sirfsoc_pwrc_toggle_interrupts(pwrcdrv, false);
  79 }
  80
  81 static const struct of_device_id sirfsoc_pwrc_of_match[] = {
  82         { .compatible = "sirf,prima2-pwrc" },
  83         {},
  84 }
  85 MODULE_DEVICE_TABLE(of, sirfsoc_pwrc_of_match);
  86
  87 static int sirfsoc_pwrc_probe(struct platform_device *pdev)
  88 {
  89         struct device_node *np = pdev->dev.of_node;
  90         struct sirfsoc_pwrc_drvdata *pwrcdrv;
  91         int irq;
  92         int error;
  93
  94         pwrcdrv = devm_kzalloc(&pdev->dev, sizeof(struct sirfsoc_pwrc_drvdata),
  95                                GFP_KERNEL);
  96         if (!pwrcdrv) {
  97                 dev_info(&pdev->dev, "Not enough memory for the device data\n");
  98                 return -ENOMEM;
  99         }
 100
 101         /*
 102          * We can't use of_iomap because pwrc is not mapped in memory,
 103          * the so-called base address is only offset in rtciobrg
 104          */
 105         error = of_property_read_u32(np, "reg", &pwrcdrv->pwrc_base);
 106         if (error) {
 107                 dev_err(&pdev->dev,
 108                         "unable to find base address of pwrc node in dtb\n");
 109                 return error;
 110         }
 111
 112         pwrcdrv->input = devm_input_allocate_device(&pdev->dev);
 113         if (!pwrcdrv->input)
 114                 return -ENOMEM;
 115
 116         pwrcdrv->input->name = "sirfsoc pwrckey";
 117         pwrcdrv->input->phys = "pwrc/input0";
 118         pwrcdrv->input->evbit[0] = BIT_MASK(EV_PWR);
 119
 120         pwrcdrv->input->open = sirfsoc_pwrc_open;
 121         pwrcdrv->input->close = sirfsoc_pwrc_close;
 122
 123         input_set_drvdata(pwrcdrv->input, pwrcdrv);
 124
 125         /* Make sure the device is quiesced */
 126         sirfsoc_pwrc_toggle_interrupts(pwrcdrv, false);
 127
 128         irq = platform_get_irq(pdev, 0);
 129         error = devm_request_irq(&pdev->dev, irq,
 130                                  sirfsoc_pwrc_isr, IRQF_SHARED,
 131                                  "sirfsoc_pwrc_int", pwrcdrv);
 132         if (error) {
 133                 dev_err(&pdev->dev, "unable to claim irq %d, error: %d\n",
 134                         irq, error);
 135                 return error;
 136         }
 137
 138         error = input_register_device(pwrcdrv->input);
 139         if (error) {
 140                 dev_err(&pdev->dev,
 141                         "unable to register input device, error: %d\n",
 142                         error);
 143                 return error;
 144         }
 145
 146         platform_set_drvdata(pdev, pwrcdrv);
 147         device_init_wakeup(&pdev->dev, 1);
 148
 149         return 0;
 150 }
 151
 152 static int sirfsoc_pwrc_remove(struct platform_device *pdev)
 153 {
 154         device_init_wakeup(&pdev->dev, 0);
 155
 156         return 0;
 157 }
 158
 159 #ifdef CONFIG_PM_SLEEP
 160 static int pwrc_resume(struct device *dev)
 161 {
 162         struct platform_device *pdev = to_platform_device(dev);
 163         struct sirfsoc_pwrc_drvdata *pwrcdrv = platform_get_drvdata(pdev);
 164         struct input_dev *input = pwrcdrv->input;
 165
 166         /*
 167          * Do not mask pwrc interrupt as we want pwrc work as a wakeup source
 168          * if users touch X_ONKEY_B, see arch/arm/mach-prima2/pm.c
 169          */
 170         mutex_lock(&input->mutex);
 171         if (input->users)
 172                 sirfsoc_pwrc_toggle_interrupts(pwrcdrv, true);
 173         mutex_unlock(&input->mutex);
 174
 175         return 0;
 176 }
 177 #endif
 178
 179 static SIMPLE_DEV_PM_OPS(sirfsoc_pwrc_pm_ops, NULL, pwrc_resume);
 180
 181 static struct platform_driver sirfsoc_pwrc_driver = {
 182         .probe          = sirfsoc_pwrc_probe,
 183         .remove         = sirfsoc_pwrc_remove,
 184         .driver         = {
 185                 .name   = "sirfsoc-pwrc",
 186                 .owner  = THIS_MODULE,
 187                 .pm     = &sirfsoc_pwrc_pm_ops,
 188                 .of_match_table = sirfsoc_pwrc_of_match,
 189         }
 190 };
 191
 192 module_platform_driver(sirfsoc_pwrc_driver);
 193
 194 MODULE_LICENSE("GPLv2");
 195 MODULE_AUTHOR("Binghua Duan <Binghua.Duan@csr.com>, Xianglong Du <Xianglong.Du@csr.com>");
 196 MODULE_DESCRIPTION("CSR Prima2 PWRC Driver");
 197 MODULE_ALIAS("platform:sirfsoc-pwrc");