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 #include <linux/acpi.h>
  26
  27 enum {
  28         REG_READ        = 0x00,
  29         REG_SET_PAGE    = 0x00,
  30         REG_LEN         = 0x04,
  31         REG_DATA        = 0x08,
  32
  33         PAGE_NAME       = 0x00000,
  34         PAGE_EVBITS     = 0x10000,
  35         PAGE_ABSDATA    = 0x20000 | EV_ABS,
  36 };
  37
  38 struct event_dev {
  39         struct input_dev *input;
  40         int irq;
  41         void __iomem *addr;
  42         char name[0];
  43 };
  44
  45 static irqreturn_t events_interrupt(int irq, void *dev_id)
  46 {
  47         struct event_dev *edev = dev_id;
  48         unsigned type, code, value;
  49
  50         type = __raw_readl(edev->addr + REG_READ);
  51         code = __raw_readl(edev->addr + REG_READ);
  52         value = __raw_readl(edev->addr + REG_READ);
  53
  54         input_event(edev->input, type, code, value);
  55         input_sync(edev->input);
  56         return IRQ_HANDLED;
  57 }
  58
  59 static void events_import_bits(struct event_dev *edev,
  60                         unsigned long bits[], unsigned type, size_t count)
  61 {
  62         void __iomem *addr = edev->addr;
  63         int i, j;
  64         size_t size;
  65         uint8_t val;
  66
  67         __raw_writel(PAGE_EVBITS | type, addr + REG_SET_PAGE);
  68
  69         size = __raw_readl(addr + REG_LEN) * 8;
  70         if (size < count)
  71                 count = size;
  72
  73         addr += REG_DATA;
  74         for (i = 0; i < count; i += 8) {
  75                 val = __raw_readb(addr++);
  76                 for (j = 0; j < 8; j++)
  77                         if (val & 1 << j)
  78                                 set_bit(i + j, bits);
  79         }
  80 }
  81
  82 static void events_import_abs_params(struct event_dev *edev)
  83 {
  84         struct input_dev *input_dev = edev->input;
  85         void __iomem *addr = edev->addr;
  86         u32 val[4];
  87         int count;
  88         int i, j;
  89
  90         __raw_writel(PAGE_ABSDATA, addr + REG_SET_PAGE);
  91
  92         count = __raw_readl(addr + REG_LEN) / sizeof(val);
  93         if (count > ABS_MAX)
  94                 count = ABS_MAX;
  95
  96         for (i = 0; i < count; i++) {
  97                 if (!test_bit(i, input_dev->absbit))
  98                         continue;
  99
 100                 for (j = 0; j < ARRAY_SIZE(val); j++) {
 101                         int offset = (i * ARRAY_SIZE(val) + j) * sizeof(u32);
 102                         val[j] = __raw_readl(edev->addr + REG_DATA + offset);
 103                 }
 104
 105                 input_set_abs_params(input_dev, i,
 106                                      val[0], val[1], val[2], val[3]);
 107         }
 108 }
 109
 110 static int events_probe(struct platform_device *pdev)
 111 {
 112         struct input_dev *input_dev;
 113         struct event_dev *edev;
 114         struct resource *res;
 115         unsigned keymapnamelen;
 116         void __iomem *addr;
 117         int irq;
 118         int i;
 119         int error;
 120
 121         irq = platform_get_irq(pdev, 0);
 122         if (irq < 0)
 123                 return -EINVAL;
 124
 125         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 126         if (!res)
 127                 return -EINVAL;
 128
 129         addr = devm_ioremap(&pdev->dev, res->start, 4096);
 130         if (!addr)
 131                 return -ENOMEM;
 132
 133         __raw_writel(PAGE_NAME, addr + REG_SET_PAGE);
 134         keymapnamelen = __raw_readl(addr + REG_LEN);
 135
 136         edev = devm_kzalloc(&pdev->dev,
 137                             sizeof(struct event_dev) + keymapnamelen + 1,
 138                             GFP_KERNEL);
 139         if (!edev)
 140                 return -ENOMEM;
 141
 142         input_dev = devm_input_allocate_device(&pdev->dev);
 143         if (!input_dev)
 144                 return -ENOMEM;
 145
 146         edev->input = input_dev;
 147         edev->addr = addr;
 148         edev->irq = irq;
 149
 150         for (i = 0; i < keymapnamelen; i++)
 151                 edev->name[i] = __raw_readb(edev->addr + REG_DATA + i);
 152
 153         pr_debug("events_probe() keymap=%s\n", edev->name);
 154
 155         input_dev->name = edev->name;
 156         input_dev->id.bustype = BUS_HOST;
 157
 158         events_import_bits(edev, input_dev->evbit, EV_SYN, EV_MAX);
 159         events_import_bits(edev, input_dev->keybit, EV_KEY, KEY_MAX);
 160         events_import_bits(edev, input_dev->relbit, EV_REL, REL_MAX);
 161         events_import_bits(edev, input_dev->absbit, EV_ABS, ABS_MAX);
 162         events_import_bits(edev, input_dev->mscbit, EV_MSC, MSC_MAX);
 163         events_import_bits(edev, input_dev->ledbit, EV_LED, LED_MAX);
 164         events_import_bits(edev, input_dev->sndbit, EV_SND, SND_MAX);
 165         events_import_bits(edev, input_dev->ffbit, EV_FF, FF_MAX);
 166         events_import_bits(edev, input_dev->swbit, EV_SW, SW_MAX);
 167
 168         events_import_abs_params(edev);
 169
 170         error = devm_request_irq(&pdev->dev, edev->irq, events_interrupt, 0,
 171                                  "goldfish-events-keypad", edev);
 172         if (error)
 173                 return error;
 174
 175         error = input_register_device(input_dev);
 176         if (error)
 177                 return error;
 178
 179         return 0;
 180 }
 181
 182 static const struct of_device_id goldfish_events_of_match[] = {
 183         { .compatible = "google,goldfish-events-keypad", },
 184         {},
 185 };
 186 MODULE_DEVICE_TABLE(of, goldfish_events_of_match);
 187
 188 #ifdef CONFIG_ACPI
 189 static const struct acpi_device_id goldfish_events_acpi_match[] = {
 190         { "GFSH0002", 0 },
 191         { },
 192 };
 193 MODULE_DEVICE_TABLE(acpi, goldfish_events_acpi_match);
 194 #endif
 195
 196 static struct platform_driver events_driver = {
 197         .probe  = events_probe,
 198         .driver = {
 199                 .name   = "goldfish_events",
 200                 .of_match_table = goldfish_events_of_match,
 201                 .acpi_match_table = ACPI_PTR(goldfish_events_acpi_match),
 202         },
 203 };
 204
 205 module_platform_driver(events_driver);
 206
 207 MODULE_AUTHOR("Brian Swetland");
 208 MODULE_DESCRIPTION("Goldfish Event Device");
 209 MODULE_LICENSE("GPL");