drivers/macintosh/ams/ams-core.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Apple Motion Sensor driver
   4  *
   5  * Copyright (C) 2005 Stelian Pop (stelian@popies.net)
   6  * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/types.h>
  11 #include <linux/errno.h>
  12 #include <linux/init.h>
  13 #include <linux/of_platform.h>
  14 #include <asm/pmac_pfunc.h>
  15
  16 #include "ams.h"
  17
  18 /* There is only one motion sensor per machine */
  19 struct ams ams_info;
  20
  21 static bool verbose;
  22 module_param(verbose, bool, 0644);
  23 MODULE_PARM_DESC(verbose, "Show free falls and shocks in kernel output");
  24
  25 /* Call with ams_info.lock held! */
  26 void ams_sensors(s8 *x, s8 *y, s8 *z)
  27 {
  28         u32 orient = ams_info.vflag? ams_info.orient1 : ams_info.orient2;
  29
  30         if (orient & 0x80)
  31                 /* X and Y swapped */
  32                 ams_info.get_xyz(y, x, z);
  33         else
  34                 ams_info.get_xyz(x, y, z);
  35
  36         if (orient & 0x04)
  37                 *z = ~(*z);
  38         if (orient & 0x02)
  39                 *y = ~(*y);
  40         if (orient & 0x01)
  41                 *x = ~(*x);
  42 }
  43
  44 static ssize_t ams_show_current(struct device *dev,
  45         struct device_attribute *attr, char *buf)
  46 {
  47         s8 x, y, z;
  48
  49         mutex_lock(&ams_info.lock);
  50         ams_sensors(&x, &y, &z);
  51         mutex_unlock(&ams_info.lock);
  52
  53         return snprintf(buf, PAGE_SIZE, "%d %d %d\n", x, y, z);
  54 }
  55
  56 static DEVICE_ATTR(current, S_IRUGO, ams_show_current, NULL);
  57
  58 static void ams_handle_irq(void *data)
  59 {
  60         enum ams_irq irq = *((enum ams_irq *)data);
  61
  62         spin_lock(&ams_info.irq_lock);
  63
  64         ams_info.worker_irqs |= irq;
  65         schedule_work(&ams_info.worker);
  66
  67         spin_unlock(&ams_info.irq_lock);
  68 }
  69
  70 static enum ams_irq ams_freefall_irq_data = AMS_IRQ_FREEFALL;
  71 static struct pmf_irq_client ams_freefall_client = {
  72         .owner = THIS_MODULE,
  73         .handler = ams_handle_irq,
  74         .data = &ams_freefall_irq_data,
  75 };
  76
  77 static enum ams_irq ams_shock_irq_data = AMS_IRQ_SHOCK;
  78 static struct pmf_irq_client ams_shock_client = {
  79         .owner = THIS_MODULE,
  80         .handler = ams_handle_irq,
  81         .data = &ams_shock_irq_data,
  82 };
  83
  84 /* Once hard disk parking is implemented in the kernel, this function can
  85  * trigger it.
  86  */
  87 static void ams_worker(struct work_struct *work)
  88 {
  89         unsigned long flags;
  90         u8 irqs_to_clear;
  91
  92         mutex_lock(&ams_info.lock);
  93
  94         spin_lock_irqsave(&ams_info.irq_lock, flags);
  95         irqs_to_clear = ams_info.worker_irqs;
  96
  97         if (ams_info.worker_irqs & AMS_IRQ_FREEFALL) {
  98                 if (verbose)
  99                         printk(KERN_INFO "ams: freefall detected!\n");
 100
 101                 ams_info.worker_irqs &= ~AMS_IRQ_FREEFALL;
 102         }
 103
 104         if (ams_info.worker_irqs & AMS_IRQ_SHOCK) {
 105                 if (verbose)
 106                         printk(KERN_INFO "ams: shock detected!\n");
 107
 108                 ams_info.worker_irqs &= ~AMS_IRQ_SHOCK;
 109         }
 110
 111         spin_unlock_irqrestore(&ams_info.irq_lock, flags);
 112
 113         ams_info.clear_irq(irqs_to_clear);
 114
 115         mutex_unlock(&ams_info.lock);
 116 }
 117
 118 /* Call with ams_info.lock held! */
 119 int ams_sensor_attach(void)
 120 {
 121         int result;
 122         const u32 *prop;
 123
 124         /* Get orientation */
 125         prop = of_get_property(ams_info.of_node, "orientation", NULL);
 126         if (!prop)
 127                 return -ENODEV;
 128         ams_info.orient1 = *prop;
 129         ams_info.orient2 = *(prop + 1);
 130
 131         /* Register freefall interrupt handler */
 132         result = pmf_register_irq_client(ams_info.of_node,
 133                         "accel-int-1",
 134                         &ams_freefall_client);
 135         if (result < 0)
 136                 return -ENODEV;
 137
 138         /* Reset saved irqs */
 139         ams_info.worker_irqs = 0;
 140
 141         /* Register shock interrupt handler */
 142         result = pmf_register_irq_client(ams_info.of_node,
 143                         "accel-int-2",
 144                         &ams_shock_client);
 145         if (result < 0)
 146                 goto release_freefall;
 147
 148         /* Create device */
 149         ams_info.of_dev = of_platform_device_create(ams_info.of_node, "ams", NULL);
 150         if (!ams_info.of_dev) {
 151                 result = -ENODEV;
 152                 goto release_shock;
 153         }
 154
 155         /* Create attributes */
 156         result = device_create_file(&ams_info.of_dev->dev, &dev_attr_current);
 157         if (result)
 158                 goto release_of;
 159
 160         ams_info.vflag = !!(ams_info.get_vendor() & 0x10);
 161
 162         /* Init input device */
 163         result = ams_input_init();
 164         if (result)
 165                 goto release_device_file;
 166
 167         return result;
 168 release_device_file:
 169         device_remove_file(&ams_info.of_dev->dev, &dev_attr_current);
 170 release_of:
 171         of_device_unregister(ams_info.of_dev);
 172 release_shock:
 173         pmf_unregister_irq_client(&ams_shock_client);
 174 release_freefall:
 175         pmf_unregister_irq_client(&ams_freefall_client);
 176         return result;
 177 }
 178
 179 int __init ams_init(void)
 180 {
 181         struct device_node *np;
 182
 183         spin_lock_init(&ams_info.irq_lock);
 184         mutex_init(&ams_info.lock);
 185         INIT_WORK(&ams_info.worker, ams_worker);
 186
 187 #ifdef CONFIG_SENSORS_AMS_I2C
 188         np = of_find_node_by_name(NULL, "accelerometer");
 189         if (np && of_device_is_compatible(np, "AAPL,accelerometer_1"))
 190                 /* Found I2C motion sensor */
 191                 return ams_i2c_init(np);
 192 #endif
 193
 194 #ifdef CONFIG_SENSORS_AMS_PMU
 195         np = of_find_node_by_name(NULL, "sms");
 196         if (np && of_device_is_compatible(np, "sms"))
 197                 /* Found PMU motion sensor */
 198                 return ams_pmu_init(np);
 199 #endif
 200         return -ENODEV;
 201 }
 202
 203 void ams_sensor_detach(void)
 204 {
 205         /* Remove input device */
 206         ams_input_exit();
 207
 208         /* Remove attributes */
 209         device_remove_file(&ams_info.of_dev->dev, &dev_attr_current);
 210
 211         /* Flush interrupt worker
 212          *
 213          * We do this after ams_info.exit(), because an interrupt might
 214          * have arrived before disabling them.
 215          */
 216         flush_work(&ams_info.worker);
 217
 218         /* Remove device */
 219         of_device_unregister(ams_info.of_dev);
 220
 221         /* Remove handler */
 222         pmf_unregister_irq_client(&ams_shock_client);
 223         pmf_unregister_irq_client(&ams_freefall_client);
 224 }
 225
 226 static void __exit ams_exit(void)
 227 {
 228         /* Shut down implementation */
 229         ams_info.exit();
 230 }
 231
 232 MODULE_AUTHOR("Stelian Pop, Michael Hanselmann");
 233 MODULE_DESCRIPTION("Apple Motion Sensor driver");
 234 MODULE_LICENSE("GPL");
 235
 236 module_init(ams_init);
 237 module_exit(ams_exit);