drivers/input/misc/bfin_rotary.c

   1 /*
   2  * Rotary counter driver for Analog Devices Blackfin Processors
   3  *
   4  * Copyright 2008-2009 Analog Devices Inc.
   5  * Licensed under the GPL-2 or later.
   6  */
   7
   8 #include <linux/module.h>
   9 #include <linux/init.h>
  10 #include <linux/interrupt.h>
  11 #include <linux/irq.h>
  12 #include <linux/pm.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/input.h>
  15 #include <linux/slab.h>
  16
  17 #include <asm/portmux.h>
  18 #include <asm/bfin_rotary.h>
  19
  20 static const u16 per_cnt[] = {
  21         P_CNT_CUD,
  22         P_CNT_CDG,
  23         P_CNT_CZM,
  24         0
  25 };
  26
  27 struct bfin_rot {
  28         struct input_dev *input;
  29         int irq;
  30         unsigned int up_key;
  31         unsigned int down_key;
  32         unsigned int button_key;
  33         unsigned int rel_code;
  34         unsigned short cnt_config;
  35         unsigned short cnt_imask;
  36         unsigned short cnt_debounce;
  37 };
  38
  39 static void report_key_event(struct input_dev *input, int keycode)
  40 {
  41         /* simulate a press-n-release */
  42         input_report_key(input, keycode, 1);
  43         input_sync(input);
  44         input_report_key(input, keycode, 0);
  45         input_sync(input);
  46 }
  47
  48 static void report_rotary_event(struct bfin_rot *rotary, int delta)
  49 {
  50         struct input_dev *input = rotary->input;
  51
  52         if (rotary->up_key) {
  53                 report_key_event(input,
  54                                  delta > 0 ? rotary->up_key : rotary->down_key);
  55         } else {
  56                 input_report_rel(input, rotary->rel_code, delta);
  57                 input_sync(input);
  58         }
  59 }
  60
  61 static irqreturn_t bfin_rotary_isr(int irq, void *dev_id)
  62 {
  63         struct platform_device *pdev = dev_id;
  64         struct bfin_rot *rotary = platform_get_drvdata(pdev);
  65         int delta;
  66
  67         switch (bfin_read_CNT_STATUS()) {
  68
  69         case ICII:
  70                 break;
  71
  72         case UCII:
  73         case DCII:
  74                 delta = bfin_read_CNT_COUNTER();
  75                 if (delta)
  76                         report_rotary_event(rotary, delta);
  77                 break;
  78
  79         case CZMII:
  80                 report_key_event(rotary->input, rotary->button_key);
  81                 break;
  82
  83         default:
  84                 break;
  85         }
  86
  87         bfin_write_CNT_COMMAND(W1LCNT_ZERO);    /* Clear COUNTER */
  88         bfin_write_CNT_STATUS(-1);      /* Clear STATUS */
  89
  90         return IRQ_HANDLED;
  91 }
  92
  93 static int bfin_rotary_probe(struct platform_device *pdev)
  94 {
  95         struct bfin_rotary_platform_data *pdata = pdev->dev.platform_data;
  96         struct bfin_rot *rotary;
  97         struct input_dev *input;
  98         int error;
  99
 100         /* Basic validation */
 101         if ((pdata->rotary_up_key && !pdata->rotary_down_key) ||
 102             (!pdata->rotary_up_key && pdata->rotary_down_key)) {
 103                 return -EINVAL;
 104         }
 105
 106         error = peripheral_request_list(per_cnt, dev_name(&pdev->dev));
 107         if (error) {
 108                 dev_err(&pdev->dev, "requesting peripherals failed\n");
 109                 return error;
 110         }
 111
 112         rotary = kzalloc(sizeof(struct bfin_rot), GFP_KERNEL);
 113         input = input_allocate_device();
 114         if (!rotary || !input) {
 115                 error = -ENOMEM;
 116                 goto out1;
 117         }
 118
 119         rotary->input = input;
 120
 121         rotary->up_key = pdata->rotary_up_key;
 122         rotary->down_key = pdata->rotary_down_key;
 123         rotary->button_key = pdata->rotary_button_key;
 124         rotary->rel_code = pdata->rotary_rel_code;
 125
 126         error = rotary->irq = platform_get_irq(pdev, 0);
 127         if (error < 0)
 128                 goto out1;
 129
 130         input->name = pdev->name;
 131         input->phys = "bfin-rotary/input0";
 132         input->dev.parent = &pdev->dev;
 133
 134         input_set_drvdata(input, rotary);
 135
 136         input->id.bustype = BUS_HOST;
 137         input->id.vendor = 0x0001;
 138         input->id.product = 0x0001;
 139         input->id.version = 0x0100;
 140
 141         if (rotary->up_key) {
 142                 __set_bit(EV_KEY, input->evbit);
 143                 __set_bit(rotary->up_key, input->keybit);
 144                 __set_bit(rotary->down_key, input->keybit);
 145         } else {
 146                 __set_bit(EV_REL, input->evbit);
 147                 __set_bit(rotary->rel_code, input->relbit);
 148         }
 149
 150         if (rotary->button_key) {
 151                 __set_bit(EV_KEY, input->evbit);
 152                 __set_bit(rotary->button_key, input->keybit);
 153         }
 154
 155         error = request_irq(rotary->irq, bfin_rotary_isr,
 156                             0, dev_name(&pdev->dev), pdev);
 157         if (error) {
 158                 dev_err(&pdev->dev,
 159                         "unable to claim irq %d; error %d\n",
 160                         rotary->irq, error);
 161                 goto out1;
 162         }
 163
 164         error = input_register_device(input);
 165         if (error) {
 166                 dev_err(&pdev->dev,
 167                         "unable to register input device (%d)\n", error);
 168                 goto out2;
 169         }
 170
 171         if (pdata->rotary_button_key)
 172                 bfin_write_CNT_IMASK(CZMIE);
 173
 174         if (pdata->mode & ROT_DEBE)
 175                 bfin_write_CNT_DEBOUNCE(pdata->debounce & DPRESCALE);
 176
 177         if (pdata->mode)
 178                 bfin_write_CNT_CONFIG(bfin_read_CNT_CONFIG() |
 179                                         (pdata->mode & ~CNTE));
 180
 181         bfin_write_CNT_IMASK(bfin_read_CNT_IMASK() | UCIE | DCIE);
 182         bfin_write_CNT_CONFIG(bfin_read_CNT_CONFIG() | CNTE);
 183
 184         platform_set_drvdata(pdev, rotary);
 185         device_init_wakeup(&pdev->dev, 1);
 186
 187         return 0;
 188
 189 out2:
 190         free_irq(rotary->irq, pdev);
 191 out1:
 192         input_free_device(input);
 193         kfree(rotary);
 194         peripheral_free_list(per_cnt);
 195
 196         return error;
 197 }
 198
 199 static int bfin_rotary_remove(struct platform_device *pdev)
 200 {
 201         struct bfin_rot *rotary = platform_get_drvdata(pdev);
 202
 203         bfin_write_CNT_CONFIG(0);
 204         bfin_write_CNT_IMASK(0);
 205
 206         free_irq(rotary->irq, pdev);
 207         input_unregister_device(rotary->input);
 208         peripheral_free_list(per_cnt);
 209
 210         kfree(rotary);
 211         platform_set_drvdata(pdev, NULL);
 212
 213         return 0;
 214 }
 215
 216 #ifdef CONFIG_PM
 217 static int bfin_rotary_suspend(struct device *dev)
 218 {
 219         struct platform_device *pdev = to_platform_device(dev);
 220         struct bfin_rot *rotary = platform_get_drvdata(pdev);
 221
 222         rotary->cnt_config = bfin_read_CNT_CONFIG();
 223         rotary->cnt_imask = bfin_read_CNT_IMASK();
 224         rotary->cnt_debounce = bfin_read_CNT_DEBOUNCE();
 225
 226         if (device_may_wakeup(&pdev->dev))
 227                 enable_irq_wake(rotary->irq);
 228
 229         return 0;
 230 }
 231
 232 static int bfin_rotary_resume(struct device *dev)
 233 {
 234         struct platform_device *pdev = to_platform_device(dev);
 235         struct bfin_rot *rotary = platform_get_drvdata(pdev);
 236
 237         bfin_write_CNT_DEBOUNCE(rotary->cnt_debounce);
 238         bfin_write_CNT_IMASK(rotary->cnt_imask);
 239         bfin_write_CNT_CONFIG(rotary->cnt_config & ~CNTE);
 240
 241         if (device_may_wakeup(&pdev->dev))
 242                 disable_irq_wake(rotary->irq);
 243
 244         if (rotary->cnt_config & CNTE)
 245                 bfin_write_CNT_CONFIG(rotary->cnt_config);
 246
 247         return 0;
 248 }
 249
 250 static const struct dev_pm_ops bfin_rotary_pm_ops = {
 251         .suspend        = bfin_rotary_suspend,
 252         .resume         = bfin_rotary_resume,
 253 };
 254 #endif
 255
 256 static struct platform_driver bfin_rotary_device_driver = {
 257         .probe          = bfin_rotary_probe,
 258         .remove         = bfin_rotary_remove,
 259         .driver         = {
 260                 .name   = "bfin-rotary",
 261                 .owner  = THIS_MODULE,
 262 #ifdef CONFIG_PM
 263                 .pm     = &bfin_rotary_pm_ops,
 264 #endif
 265         },
 266 };
 267 module_platform_driver(bfin_rotary_device_driver);
 268
 269 MODULE_LICENSE("GPL");
 270 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
 271 MODULE_DESCRIPTION("Rotary Counter driver for Blackfin Processors");
 272 MODULE_ALIAS("platform:bfin-rotary");