drivers/input/keyboard/goldfish_events.c

   1 /*
   2  * Copyright (C) 2007 Google, Inc.
   3  * Copyright (C) 2012 Intel, Inc.
   4  *
   5  * This software is licensed under the terms of the GNU General Public
   6  * License version 2, as published by the Free Software Foundation, and
   7  * may be copied, distributed, and modified under those terms.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/types.h>
  19 #include <linux/input.h>
  20 #include <linux/kernel.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/slab.h>
  23 #include <linux/irq.h>
  24 #include <linux/io.h>
  25
  26 enum {
  27         REG_READ        = 0x00,
  28         REG_SET_PAGE    = 0x00,
  29         REG_LEN         = 0x04,
  30         REG_DATA        = 0x08,
  31
  32         PAGE_NAME       = 0x00000,
  33         PAGE_EVBITS     = 0x10000,
  34         PAGE_ABSDATA    = 0x20000 | EV_ABS,
  35 };
  36
  37 struct event_dev {
  38         struct input_dev *input;
  39         int irq;
  40         void __iomem *addr;
  41         char name[0];
  42 };
  43
  44 static irqreturn_t events_interrupt(int irq, void *dev_id)
  45 {
  46         struct event_dev *edev = dev_id;
  47         unsigned type, code, value;
  48
  49         type = __raw_readl(edev->addr + REG_READ);
  50         code = __raw_readl(edev->addr + REG_READ);
  51         value = __raw_readl(edev->addr + REG_READ);
  52
  53         input_event(edev->input, type, code, value);
  54         input_sync(edev->input);
  55         return IRQ_HANDLED;
  56 }
  57
  58 static void events_import_bits(struct event_dev *edev,
  59                         unsigned long bits[], unsigned type, size_t count)
  60 {
  61         void __iomem *addr = edev->addr;
  62         int i, j;
  63         size_t size;
  64         uint8_t val;
  65
  66         __raw_writel(PAGE_EVBITS | type, addr + REG_SET_PAGE);
  67
  68         size = __raw_readl(addr + REG_LEN) * 8;
  69         if (size < count)
  70                 count = size;
  71
  72         addr += REG_DATA;
  73         for (i = 0; i < count; i += 8) {
  74                 val = __raw_readb(addr++);
  75                 for (j = 0; j < 8; j++)
  76                         if (val & 1 << j)
  77                                 set_bit(i + j, bits);
  78         }
  79 }
  80
  81 static void events_import_abs_params(struct event_dev *edev)
  82 {
  83         struct input_dev *input_dev = edev->input;
  84         void __iomem *addr = edev->addr;
  85         u32 val[4];
  86         int count;
  87         int i, j;
  88
  89         __raw_writel(PAGE_ABSDATA, addr + REG_SET_PAGE);
  90
  91         count = __raw_readl(addr + REG_LEN) / sizeof(val);
  92         if (count > ABS_MAX)
  93                 count = ABS_MAX;
  94
  95         for (i = 0; i < count; i++) {
  96                 if (!test_bit(i, input_dev->absbit))
  97                         continue;
  98
  99                 for (j = 0; j < ARRAY_SIZE(val); j++) {
 100                         int offset = (i * ARRAY_SIZE(val) + j) * sizeof(u32);
 101                         val[j] = __raw_readl(edev->addr + REG_DATA + offset);
 102                 }
 103
 104                 input_set_abs_params(input_dev, i,
 105                                      val[0], val[1], val[2], val[3]);
 106         }
 107 }
 108
 109 static int events_probe(struct platform_device *pdev)
 110 {
 111         struct input_dev *input_dev;
 112         struct event_dev *edev;
 113         struct resource *res;
 114         unsigned keymapnamelen;
 115         void __iomem *addr;
 116         int irq;
 117         int i;
 118         int error;
 119
 120         irq = platform_get_irq(pdev, 0);
 121         if (irq < 0)
 122                 return -EINVAL;
 123
 124         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 125         if (!res)
 126                 return -EINVAL;
 127
 128         addr = devm_ioremap(&pdev->dev, res->start, 4096);
 129         if (!addr)
 130                 return -ENOMEM;
 131
 132         __raw_writel(PAGE_NAME, addr + REG_SET_PAGE);
 133         keymapnamelen = __raw_readl(addr + REG_LEN);
 134
 135         edev = devm_kzalloc(&pdev->dev,
 136                             sizeof(struct event_dev) + keymapnamelen + 1,
 137                             GFP_KERNEL);
 138         if (!edev)
 139                 return -ENOMEM;
 140
 141         input_dev = devm_input_allocate_device(&pdev->dev);
 142         if (!input_dev)
 143                 return -ENOMEM;
 144
 145         edev->input = input_dev;
 146         edev->addr = addr;
 147         edev->irq = irq;
 148
 149         for (i = 0; i < keymapnamelen; i++)
 150                 edev->name[i] = __raw_readb(edev->addr + REG_DATA + i);
 151
 152         pr_debug("events_probe() keymap=%s\n", edev->name);
 153
 154         input_dev->name = edev->name;
 155         input_dev->id.bustype = BUS_HOST;
 156
 157         events_import_bits(edev, input_dev->evbit, EV_SYN, EV_MAX);
 158         events_import_bits(edev, input_dev->keybit, EV_KEY, KEY_MAX);
 159         events_import_bits(edev, input_dev->relbit, EV_REL, REL_MAX);
 160         events_import_bits(edev, input_dev->absbit, EV_ABS, ABS_MAX);
 161         events_import_bits(edev, input_dev->mscbit, EV_MSC, MSC_MAX);
 162         events_import_bits(edev, input_dev->ledbit, EV_LED, LED_MAX);
 163         events_import_bits(edev, input_dev->sndbit, EV_SND, SND_MAX);
 164         events_import_bits(edev, input_dev->ffbit, EV_FF, FF_MAX);
 165         events_import_bits(edev, input_dev->swbit, EV_SW, SW_MAX);
 166
 167         events_import_abs_params(edev);
 168
 169         error = devm_request_irq(&pdev->dev, edev->irq, events_interrupt, 0,
 170                                  "goldfish-events-keypad", edev);
 171         if (error)
 172                 return error;
 173
 174         error = input_register_device(input_dev);
 175         if (error)
 176                 return error;
 177
 178         return 0;
 179 }
 180
 181 static struct platform_driver events_driver = {
 182         .probe  = events_probe,
 183         .driver = {
 184                 .owner  = THIS_MODULE,
 185                 .name   = "goldfish_events",
 186         },
 187 };
 188
 189 module_platform_driver(events_driver);
 190
 191 MODULE_AUTHOR("Brian Swetland");
 192 MODULE_DESCRIPTION("Goldfish Event Device");
 193 MODULE_LICENSE("GPL");