macintosh/ams/ams-core.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  * Apple Motion Sensor driver
0004  *
0005  * Copyright (C) 2005 Stelian Pop (stelian@popies.net)
0006  * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)
0007  */
0008
0009 #include <linux/module.h>
0010 #include <linux/types.h>
0011 #include <linux/errno.h>
0012 #include <linux/init.h>
0013 #include <linux/of_platform.h>
0014 #include <asm/pmac_pfunc.h>
0015
0016 #include "ams.h"
0017
0018 /* There is only one motion sensor per machine */
0019 struct ams ams_info;
0020
0021 static bool verbose;
0022 module_param(verbose, bool, 0644);
0023 MODULE_PARM_DESC(verbose, "Show free falls and shocks in kernel output");
0024
0025 /* Call with ams_info.lock held! */
0026 void ams_sensors(s8 *x, s8 *y, s8 *z)
0027 {
0028     u32 orient = ams_info.vflag? ams_info.orient1 : ams_info.orient2;
0029
0030     if (orient & 0x80)
0031         /* X and Y swapped */
0032         ams_info.get_xyz(y, x, z);
0033     else
0034         ams_info.get_xyz(x, y, z);
0035
0036     if (orient & 0x04)
0037         *z = ~(*z);
0038     if (orient & 0x02)
0039         *y = ~(*y);
0040     if (orient & 0x01)
0041         *x = ~(*x);
0042 }
0043
0044 static ssize_t ams_show_current(struct device *dev,
0045     struct device_attribute *attr, char *buf)
0046 {
0047     s8 x, y, z;
0048
0049     mutex_lock(&ams_info.lock);
0050     ams_sensors(&x, &y, &z);
0051     mutex_unlock(&ams_info.lock);
0052
0053     return sysfs_emit(buf, "%d %d %d\n", x, y, z);
0054 }
0055
0056 static DEVICE_ATTR(current, S_IRUGO, ams_show_current, NULL);
0057
0058 static void ams_handle_irq(void *data)
0059 {
0060     enum ams_irq irq = *((enum ams_irq *)data);
0061
0062     spin_lock(&ams_info.irq_lock);
0063
0064     ams_info.worker_irqs |= irq;
0065     schedule_work(&ams_info.worker);
0066
0067     spin_unlock(&ams_info.irq_lock);
0068 }
0069
0070 static enum ams_irq ams_freefall_irq_data = AMS_IRQ_FREEFALL;
0071 static struct pmf_irq_client ams_freefall_client = {
0072     .owner = THIS_MODULE,
0073     .handler = ams_handle_irq,
0074     .data = &ams_freefall_irq_data,
0075 };
0076
0077 static enum ams_irq ams_shock_irq_data = AMS_IRQ_SHOCK;
0078 static struct pmf_irq_client ams_shock_client = {
0079     .owner = THIS_MODULE,
0080     .handler = ams_handle_irq,
0081     .data = &ams_shock_irq_data,
0082 };
0083
0084 /* Once hard disk parking is implemented in the kernel, this function can
0085  * trigger it.
0086  */
0087 static void ams_worker(struct work_struct *work)
0088 {
0089     unsigned long flags;
0090     u8 irqs_to_clear;
0091
0092     mutex_lock(&ams_info.lock);
0093
0094     spin_lock_irqsave(&ams_info.irq_lock, flags);
0095     irqs_to_clear = ams_info.worker_irqs;
0096
0097     if (ams_info.worker_irqs & AMS_IRQ_FREEFALL) {
0098         if (verbose)
0099             printk(KERN_INFO "ams: freefall detected!\n");
0100
0101         ams_info.worker_irqs &= ~AMS_IRQ_FREEFALL;
0102     }
0103
0104     if (ams_info.worker_irqs & AMS_IRQ_SHOCK) {
0105         if (verbose)
0106             printk(KERN_INFO "ams: shock detected!\n");
0107
0108         ams_info.worker_irqs &= ~AMS_IRQ_SHOCK;
0109     }
0110
0111     spin_unlock_irqrestore(&ams_info.irq_lock, flags);
0112
0113     ams_info.clear_irq(irqs_to_clear);
0114
0115     mutex_unlock(&ams_info.lock);
0116 }
0117
0118 /* Call with ams_info.lock held! */
0119 int ams_sensor_attach(void)
0120 {
0121     int result;
0122     const u32 *prop;
0123
0124     /* Get orientation */
0125     prop = of_get_property(ams_info.of_node, "orientation", NULL);
0126     if (!prop)
0127         return -ENODEV;
0128     ams_info.orient1 = *prop;
0129     ams_info.orient2 = *(prop + 1);
0130
0131     /* Register freefall interrupt handler */
0132     result = pmf_register_irq_client(ams_info.of_node,
0133             "accel-int-1",
0134             &ams_freefall_client);
0135     if (result < 0)
0136         return -ENODEV;
0137
0138     /* Reset saved irqs */
0139     ams_info.worker_irqs = 0;
0140
0141     /* Register shock interrupt handler */
0142     result = pmf_register_irq_client(ams_info.of_node,
0143             "accel-int-2",
0144             &ams_shock_client);
0145     if (result < 0)
0146         goto release_freefall;
0147
0148     /* Create device */
0149     ams_info.of_dev = of_platform_device_create(ams_info.of_node, "ams", NULL);
0150     if (!ams_info.of_dev) {
0151         result = -ENODEV;
0152         goto release_shock;
0153     }
0154
0155     /* Create attributes */
0156     result = device_create_file(&ams_info.of_dev->dev, &dev_attr_current);
0157     if (result)
0158         goto release_of;
0159
0160     ams_info.vflag = !!(ams_info.get_vendor() & 0x10);
0161
0162     /* Init input device */
0163     result = ams_input_init();
0164     if (result)
0165         goto release_device_file;
0166
0167     return result;
0168 release_device_file:
0169     device_remove_file(&ams_info.of_dev->dev, &dev_attr_current);
0170 release_of:
0171     of_device_unregister(ams_info.of_dev);
0172 release_shock:
0173     pmf_unregister_irq_client(&ams_shock_client);
0174 release_freefall:
0175     pmf_unregister_irq_client(&ams_freefall_client);
0176     return result;
0177 }
0178
0179 int __init ams_init(void)
0180 {
0181     struct device_node *np;
0182
0183     spin_lock_init(&ams_info.irq_lock);
0184     mutex_init(&ams_info.lock);
0185     INIT_WORK(&ams_info.worker, ams_worker);
0186
0187 #ifdef CONFIG_SENSORS_AMS_I2C
0188     np = of_find_node_by_name(NULL, "accelerometer");
0189     if (np && of_device_is_compatible(np, "AAPL,accelerometer_1"))
0190         /* Found I2C motion sensor */
0191         return ams_i2c_init(np);
0192 #endif
0193
0194 #ifdef CONFIG_SENSORS_AMS_PMU
0195     np = of_find_node_by_name(NULL, "sms");
0196     if (np && of_device_is_compatible(np, "sms"))
0197         /* Found PMU motion sensor */
0198         return ams_pmu_init(np);
0199 #endif
0200     return -ENODEV;
0201 }
0202
0203 void ams_sensor_detach(void)
0204 {
0205     /* Remove input device */
0206     ams_input_exit();
0207
0208     /* Remove attributes */
0209     device_remove_file(&ams_info.of_dev->dev, &dev_attr_current);
0210
0211     /* Flush interrupt worker
0212      *
0213      * We do this after ams_info.exit(), because an interrupt might
0214      * have arrived before disabling them.
0215      */
0216     flush_work(&ams_info.worker);
0217
0218     /* Remove device */
0219     of_device_unregister(ams_info.of_dev);
0220
0221     /* Remove handler */
0222     pmf_unregister_irq_client(&ams_shock_client);
0223     pmf_unregister_irq_client(&ams_freefall_client);
0224 }
0225
0226 static void __exit ams_exit(void)
0227 {
0228     /* Shut down implementation */
0229     ams_info.exit();
0230 }
0231
0232 MODULE_AUTHOR("Stelian Pop, Michael Hanselmann");
0233 MODULE_DESCRIPTION("Apple Motion Sensor driver");
0234 MODULE_LICENSE("GPL");
0235
0236 module_init(ams_init);
0237 module_exit(ams_exit);