drivers/hwmon/ams/ams-core.c

   1 /*
   2  * Apple Motion Sensor driver
   3  *
   4  * Copyright (C) 2005 Stelian Pop (stelian@popies.net)
   5  * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/types.h>
  24 #include <linux/errno.h>
  25 #include <linux/init.h>
  26 #include <linux/module.h>
  27 #include <asm/pmac_pfunc.h>
  28 #include <asm/of_platform.h>
  29
  30 #include "ams.h"
  31
  32 /* There is only one motion sensor per machine */
  33 struct ams ams_info;
  34
  35 static unsigned int verbose;
  36 module_param(verbose, bool, 0644);
  37 MODULE_PARM_DESC(verbose, "Show free falls and shocks in kernel output");
  38
  39 /* Call with ams_info.lock held! */
  40 void ams_sensors(s8 *x, s8 *y, s8 *z)
  41 {
  42         u32 orient = ams_info.vflag? ams_info.orient1 : ams_info.orient2;
  43
  44         if (orient & 0x80)
  45                 /* X and Y swapped */
  46                 ams_info.get_xyz(y, x, z);
  47         else
  48                 ams_info.get_xyz(x, y, z);
  49
  50         if (orient & 0x04)
  51                 *z = ~(*z);
  52         if (orient & 0x02)
  53                 *y = ~(*y);
  54         if (orient & 0x01)
  55                 *x = ~(*x);
  56 }
  57
  58 static ssize_t ams_show_current(struct device *dev,
  59         struct device_attribute *attr, char *buf)
  60 {
  61         s8 x, y, z;
  62
  63         mutex_lock(&ams_info.lock);
  64         ams_sensors(&x, &y, &z);
  65         mutex_unlock(&ams_info.lock);
  66
  67         return snprintf(buf, PAGE_SIZE, "%d %d %d\n", x, y, z);
  68 }
  69
  70 static DEVICE_ATTR(current, S_IRUGO, ams_show_current, NULL);
  71
  72 static void ams_handle_irq(void *data)
  73 {
  74         enum ams_irq irq = *((enum ams_irq *)data);
  75
  76         spin_lock(&ams_info.irq_lock);
  77
  78         ams_info.worker_irqs |= irq;
  79         schedule_work(&ams_info.worker);
  80
  81         spin_unlock(&ams_info.irq_lock);
  82 }
  83
  84 static enum ams_irq ams_freefall_irq_data = AMS_IRQ_FREEFALL;
  85 static struct pmf_irq_client ams_freefall_client = {
  86         .owner = THIS_MODULE,
  87         .handler = ams_handle_irq,
  88         .data = &ams_freefall_irq_data,
  89 };
  90
  91 static enum ams_irq ams_shock_irq_data = AMS_IRQ_SHOCK;
  92 static struct pmf_irq_client ams_shock_client = {
  93         .owner = THIS_MODULE,
  94         .handler = ams_handle_irq,
  95         .data = &ams_shock_irq_data,
  96 };
  97
  98 /* Once hard disk parking is implemented in the kernel, this function can
  99  * trigger it.
 100  */
 101 static void ams_worker(struct work_struct *work)
 102 {
 103         mutex_lock(&ams_info.lock);
 104
 105         if (ams_info.has_device) {
 106                 unsigned long flags;
 107
 108                 spin_lock_irqsave(&ams_info.irq_lock, flags);
 109
 110                 if (ams_info.worker_irqs & AMS_IRQ_FREEFALL) {
 111                         if (verbose)
 112                                 printk(KERN_INFO "ams: freefall detected!\n");
 113
 114                         ams_info.worker_irqs &= ~AMS_IRQ_FREEFALL;
 115
 116                         /* we must call this with interrupts enabled */
 117                         spin_unlock_irqrestore(&ams_info.irq_lock, flags);
 118                         ams_info.clear_irq(AMS_IRQ_FREEFALL);
 119                         spin_lock_irqsave(&ams_info.irq_lock, flags);
 120                 }
 121
 122                 if (ams_info.worker_irqs & AMS_IRQ_SHOCK) {
 123                         if (verbose)
 124                                 printk(KERN_INFO "ams: shock detected!\n");
 125
 126                         ams_info.worker_irqs &= ~AMS_IRQ_SHOCK;
 127
 128                         /* we must call this with interrupts enabled */
 129                         spin_unlock_irqrestore(&ams_info.irq_lock, flags);
 130                         ams_info.clear_irq(AMS_IRQ_SHOCK);
 131                         spin_lock_irqsave(&ams_info.irq_lock, flags);
 132                 }
 133
 134                 spin_unlock_irqrestore(&ams_info.irq_lock, flags);
 135         }
 136
 137         mutex_unlock(&ams_info.lock);
 138 }
 139
 140 /* Call with ams_info.lock held! */
 141 int ams_sensor_attach(void)
 142 {
 143         int result;
 144         const u32 *prop;
 145
 146         /* Get orientation */
 147         prop = get_property(ams_info.of_node, "orientation", NULL);
 148         if (!prop)
 149                 return -ENODEV;
 150         ams_info.orient1 = *prop;
 151         ams_info.orient2 = *(prop + 1);
 152
 153         /* Register freefall interrupt handler */
 154         result = pmf_register_irq_client(ams_info.of_node,
 155                         "accel-int-1",
 156                         &ams_freefall_client);
 157         if (result < 0)
 158                 return -ENODEV;
 159
 160         /* Reset saved irqs */
 161         ams_info.worker_irqs = 0;
 162
 163         /* Register shock interrupt handler */
 164         result = pmf_register_irq_client(ams_info.of_node,
 165                         "accel-int-2",
 166                         &ams_shock_client);
 167         if (result < 0)
 168                 goto release_freefall;
 169
 170         /* Create device */
 171         ams_info.of_dev = of_platform_device_create(ams_info.of_node, "ams", NULL);
 172         if (!ams_info.of_dev) {
 173                 result = -ENODEV;
 174                 goto release_shock;
 175         }
 176
 177         /* Create attributes */
 178         result = device_create_file(&ams_info.of_dev->dev, &dev_attr_current);
 179         if (result)
 180                 goto release_of;
 181
 182         ams_info.vflag = !!(ams_info.get_vendor() & 0x10);
 183
 184         /* Init input device */
 185         result = ams_input_init();
 186         if (result)
 187                 goto release_device_file;
 188
 189         return result;
 190 release_device_file:
 191         device_remove_file(&ams_info.of_dev->dev, &dev_attr_current);
 192 release_of:
 193         of_device_unregister(ams_info.of_dev);
 194 release_shock:
 195         pmf_unregister_irq_client(&ams_shock_client);
 196 release_freefall:
 197         pmf_unregister_irq_client(&ams_freefall_client);
 198         return result;
 199 }
 200
 201 int __init ams_init(void)
 202 {
 203         struct device_node *np;
 204
 205         spin_lock_init(&ams_info.irq_lock);
 206         mutex_init(&ams_info.lock);
 207         INIT_WORK(&ams_info.worker, ams_worker);
 208
 209 #ifdef CONFIG_SENSORS_AMS_I2C
 210         np = of_find_node_by_name(NULL, "accelerometer");
 211         if (np && device_is_compatible(np, "AAPL,accelerometer_1"))
 212                 /* Found I2C motion sensor */
 213                 return ams_i2c_init(np);
 214 #endif
 215
 216 #ifdef CONFIG_SENSORS_AMS_PMU
 217         np = of_find_node_by_name(NULL, "sms");
 218         if (np && device_is_compatible(np, "sms"))
 219                 /* Found PMU motion sensor */
 220                 return ams_pmu_init(np);
 221 #endif
 222
 223         printk(KERN_ERR "ams: No motion sensor found.\n");
 224
 225         return -ENODEV;
 226 }
 227
 228 void ams_exit(void)
 229 {
 230         mutex_lock(&ams_info.lock);
 231
 232         if (ams_info.has_device) {
 233                 /* Remove input device */
 234                 ams_input_exit();
 235
 236                 /* Shut down implementation */
 237                 ams_info.exit();
 238
 239                 /* Flush interrupt worker
 240                  *
 241                  * We do this after ams_info.exit(), because an interrupt might
 242                  * have arrived before disabling them.
 243                  */
 244                 flush_scheduled_work();
 245
 246                 /* Remove attributes */
 247                 device_remove_file(&ams_info.of_dev->dev, &dev_attr_current);
 248
 249                 /* Remove device */
 250                 of_device_unregister(ams_info.of_dev);
 251
 252                 /* Remove handler */
 253                 pmf_unregister_irq_client(&ams_shock_client);
 254                 pmf_unregister_irq_client(&ams_freefall_client);
 255         }
 256
 257         mutex_unlock(&ams_info.lock);
 258 }
 259
 260 MODULE_AUTHOR("Stelian Pop, Michael Hanselmann");
 261 MODULE_DESCRIPTION("Apple Motion Sensor driver");
 262 MODULE_LICENSE("GPL");
 263
 264 module_init(ams_init);
 265 module_exit(ams_exit);