drivers/input/misc/axp20x-pek.c

   1 /*
   2  * axp20x power button driver.
   3  *
   4  * Copyright (C) 2013 Carlo Caione <carlo@caione.org>
   5  *
   6  * This file is subject to the terms and conditions of the GNU General
   7  * Public License. See the file "COPYING" in the main directory of this
   8  * archive for more details.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #include <linux/errno.h>
  17 #include <linux/irq.h>
  18 #include <linux/init.h>
  19 #include <linux/input.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/kernel.h>
  22 #include <linux/mfd/axp20x.h>
  23 #include <linux/module.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/regmap.h>
  26 #include <linux/slab.h>
  27
  28 #define AXP20X_PEK_STARTUP_MASK         (0xc0)
  29 #define AXP20X_PEK_SHUTDOWN_MASK        (0x03)
  30
  31 struct axp20x_pek {
  32         struct axp20x_dev *axp20x;
  33         struct input_dev *input;
  34         int irq_dbr;
  35         int irq_dbf;
  36 };
  37
  38 struct axp20x_time {
  39         unsigned int time;
  40         unsigned int idx;
  41 };
  42
  43 static const struct axp20x_time startup_time[] = {
  44         { .time = 128,  .idx = 0 },
  45         { .time = 1000, .idx = 2 },
  46         { .time = 3000, .idx = 1 },
  47         { .time = 2000, .idx = 3 },
  48 };
  49
  50 static const struct axp20x_time shutdown_time[] = {
  51         { .time = 4000,  .idx = 0 },
  52         { .time = 6000,  .idx = 1 },
  53         { .time = 8000,  .idx = 2 },
  54         { .time = 10000, .idx = 3 },
  55 };
  56
  57 struct axp20x_pek_ext_attr {
  58         const struct axp20x_time *p_time;
  59         unsigned int mask;
  60 };
  61
  62 static struct axp20x_pek_ext_attr axp20x_pek_startup_ext_attr = {
  63         .p_time = startup_time,
  64         .mask   = AXP20X_PEK_STARTUP_MASK,
  65 };
  66
  67 static struct axp20x_pek_ext_attr axp20x_pek_shutdown_ext_attr = {
  68         .p_time = shutdown_time,
  69         .mask   = AXP20X_PEK_SHUTDOWN_MASK,
  70 };
  71
  72 static struct axp20x_pek_ext_attr *get_axp_ext_attr(struct device_attribute *attr)
  73 {
  74         return container_of(attr, struct dev_ext_attribute, attr)->var;
  75 }
  76
  77 static ssize_t axp20x_show_ext_attr(struct device *dev,
  78                                     struct device_attribute *attr, char *buf)
  79 {
  80         struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
  81         struct axp20x_pek_ext_attr *axp20x_ea = get_axp_ext_attr(attr);
  82         unsigned int val;
  83         int ret, i;
  84
  85         ret = regmap_read(axp20x_pek->axp20x->regmap, AXP20X_PEK_KEY, &val);
  86         if (ret != 0)
  87                 return ret;
  88
  89         val &= axp20x_ea->mask;
  90         val >>= ffs(axp20x_ea->mask) - 1;
  91
  92         for (i = 0; i < 4; i++)
  93                 if (val == axp20x_ea->p_time[i].idx)
  94                         val = axp20x_ea->p_time[i].time;
  95
  96         return sprintf(buf, "%u\n", val);
  97 }
  98
  99 static ssize_t axp20x_store_ext_attr(struct device *dev,
 100                                      struct device_attribute *attr,
 101                                      const char *buf, size_t count)
 102 {
 103         struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
 104         struct axp20x_pek_ext_attr *axp20x_ea = get_axp_ext_attr(attr);
 105         char val_str[20];
 106         size_t len;
 107         int ret, i;
 108         unsigned int val, idx = 0;
 109         unsigned int best_err = UINT_MAX;
 110
 111         val_str[sizeof(val_str) - 1] = '\0';
 112         strncpy(val_str, buf, sizeof(val_str) - 1);
 113         len = strlen(val_str);
 114
 115         if (len && val_str[len - 1] == '\n')
 116                 val_str[len - 1] = '\0';
 117
 118         ret = kstrtouint(val_str, 10, &val);
 119         if (ret)
 120                 return ret;
 121
 122         for (i = 3; i >= 0; i--) {
 123                 unsigned int err;
 124
 125                 err = abs(axp20x_ea->p_time[i].time - val);
 126                 if (err < best_err) {
 127                         best_err = err;
 128                         idx = axp20x_ea->p_time[i].idx;
 129                 }
 130
 131                 if (!err)
 132                         break;
 133         }
 134
 135         idx <<= ffs(axp20x_ea->mask) - 1;
 136         ret = regmap_update_bits(axp20x_pek->axp20x->regmap,
 137                                  AXP20X_PEK_KEY,
 138                                  axp20x_ea->mask, idx);
 139         if (ret != 0)
 140                 return -EINVAL;
 141
 142         return count;
 143 }
 144
 145 static struct dev_ext_attribute axp20x_dev_attr_startup = {
 146         .attr   = __ATTR(startup, 0644, axp20x_show_ext_attr, axp20x_store_ext_attr),
 147         .var    = &axp20x_pek_startup_ext_attr,
 148 };
 149
 150 static struct dev_ext_attribute axp20x_dev_attr_shutdown = {
 151         .attr   = __ATTR(shutdown, 0644, axp20x_show_ext_attr, axp20x_store_ext_attr),
 152         .var    = &axp20x_pek_shutdown_ext_attr,
 153 };
 154
 155 static struct attribute *axp20x_attributes[] = {
 156         &axp20x_dev_attr_startup.attr.attr,
 157         &axp20x_dev_attr_shutdown.attr.attr,
 158         NULL,
 159 };
 160
 161 static const struct attribute_group axp20x_attribute_group = {
 162         .attrs = axp20x_attributes,
 163 };
 164
 165 static irqreturn_t axp20x_pek_irq(int irq, void *pwr)
 166 {
 167         struct input_dev *idev = pwr;
 168         struct axp20x_pek *axp20x_pek = input_get_drvdata(idev);
 169
 170         /*
 171          * The power-button is connected to ground so a falling edge (dbf)
 172          * means it is pressed.
 173          */
 174         if (irq == axp20x_pek->irq_dbf)
 175                 input_report_key(idev, KEY_POWER, true);
 176         else if (irq == axp20x_pek->irq_dbr)
 177                 input_report_key(idev, KEY_POWER, false);
 178
 179         input_sync(idev);
 180
 181         return IRQ_HANDLED;
 182 }
 183
 184 static void axp20x_remove_sysfs_group(void *_data)
 185 {
 186         struct device *dev = _data;
 187
 188         sysfs_remove_group(&dev->kobj, &axp20x_attribute_group);
 189 }
 190
 191 static int axp20x_pek_probe(struct platform_device *pdev)
 192 {
 193         struct axp20x_pek *axp20x_pek;
 194         struct axp20x_dev *axp20x;
 195         struct input_dev *idev;
 196         int error;
 197
 198         axp20x_pek = devm_kzalloc(&pdev->dev, sizeof(struct axp20x_pek),
 199                                   GFP_KERNEL);
 200         if (!axp20x_pek)
 201                 return -ENOMEM;
 202
 203         axp20x_pek->axp20x = dev_get_drvdata(pdev->dev.parent);
 204         axp20x = axp20x_pek->axp20x;
 205
 206         axp20x_pek->irq_dbr = platform_get_irq_byname(pdev, "PEK_DBR");
 207         if (axp20x_pek->irq_dbr < 0) {
 208                 dev_err(&pdev->dev, "No IRQ for PEK_DBR, error=%d\n",
 209                                 axp20x_pek->irq_dbr);
 210                 return axp20x_pek->irq_dbr;
 211         }
 212         axp20x_pek->irq_dbr = regmap_irq_get_virq(axp20x->regmap_irqc,
 213                                                   axp20x_pek->irq_dbr);
 214
 215         axp20x_pek->irq_dbf = platform_get_irq_byname(pdev, "PEK_DBF");
 216         if (axp20x_pek->irq_dbf < 0) {
 217                 dev_err(&pdev->dev, "No IRQ for PEK_DBF, error=%d\n",
 218                                 axp20x_pek->irq_dbf);
 219                 return axp20x_pek->irq_dbf;
 220         }
 221         axp20x_pek->irq_dbf = regmap_irq_get_virq(axp20x->regmap_irqc,
 222                                                   axp20x_pek->irq_dbf);
 223
 224         axp20x_pek->input = devm_input_allocate_device(&pdev->dev);
 225         if (!axp20x_pek->input)
 226                 return -ENOMEM;
 227
 228         idev = axp20x_pek->input;
 229
 230         idev->name = "axp20x-pek";
 231         idev->phys = "m1kbd/input2";
 232         idev->dev.parent = &pdev->dev;
 233
 234         input_set_capability(idev, EV_KEY, KEY_POWER);
 235
 236         input_set_drvdata(idev, axp20x_pek);
 237
 238         error = devm_request_any_context_irq(&pdev->dev, axp20x_pek->irq_dbr,
 239                                              axp20x_pek_irq, 0,
 240                                              "axp20x-pek-dbr", idev);
 241         if (error < 0) {
 242                 dev_err(axp20x->dev, "Failed to request dbr IRQ#%d: %d\n",
 243                         axp20x_pek->irq_dbr, error);
 244                 return error;
 245         }
 246
 247         error = devm_request_any_context_irq(&pdev->dev, axp20x_pek->irq_dbf,
 248                                           axp20x_pek_irq, 0,
 249                                           "axp20x-pek-dbf", idev);
 250         if (error < 0) {
 251                 dev_err(axp20x->dev, "Failed to request dbf IRQ#%d: %d\n",
 252                         axp20x_pek->irq_dbf, error);
 253                 return error;
 254         }
 255
 256         error = sysfs_create_group(&pdev->dev.kobj, &axp20x_attribute_group);
 257         if (error) {
 258                 dev_err(axp20x->dev, "Failed to create sysfs attributes: %d\n",
 259                         error);
 260                 return error;
 261         }
 262
 263         error = devm_add_action(&pdev->dev,
 264                                 axp20x_remove_sysfs_group, &pdev->dev);
 265         if (error) {
 266                 axp20x_remove_sysfs_group(&pdev->dev);
 267                 dev_err(&pdev->dev, "Failed to add sysfs cleanup action: %d\n",
 268                         error);
 269                 return error;
 270         }
 271
 272         error = input_register_device(idev);
 273         if (error) {
 274                 dev_err(axp20x->dev, "Can't register input device: %d\n",
 275                         error);
 276                 return error;
 277         }
 278
 279         platform_set_drvdata(pdev, axp20x_pek);
 280
 281         return 0;
 282 }
 283
 284 static struct platform_driver axp20x_pek_driver = {
 285         .probe          = axp20x_pek_probe,
 286         .driver         = {
 287                 .name           = "axp20x-pek",
 288         },
 289 };
 290 module_platform_driver(axp20x_pek_driver);
 291
 292 MODULE_DESCRIPTION("axp20x Power Button");
 293 MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
 294 MODULE_LICENSE("GPL");