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