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Stelian Popdcb69dd2006-12-12 18:18:30 +01001/*
2 * Apple Motion Sensor driver (PMU variant)
3 *
4 * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 */
11
12#include <linux/module.h>
13#include <linux/types.h>
14#include <linux/errno.h>
15#include <linux/init.h>
16#include <linux/adb.h>
17#include <linux/pmu.h>
18
19#include "ams.h"
20
21/* Attitude */
22#define AMS_X 0x00
23#define AMS_Y 0x01
24#define AMS_Z 0x02
25
26/* Not exactly known, maybe chip vendor */
27#define AMS_VENDOR 0x03
28
29/* Freefall registers */
30#define AMS_FF_CLEAR 0x04
31#define AMS_FF_ENABLE 0x05
32#define AMS_FF_LOW_LIMIT 0x06
33#define AMS_FF_DEBOUNCE 0x07
34
35/* Shock registers */
36#define AMS_SHOCK_CLEAR 0x08
37#define AMS_SHOCK_ENABLE 0x09
38#define AMS_SHOCK_HIGH_LIMIT 0x0a
39#define AMS_SHOCK_DEBOUNCE 0x0b
40
41/* Global interrupt and power control register */
42#define AMS_CONTROL 0x0c
43
44static u8 ams_pmu_cmd;
45
46static void ams_pmu_req_complete(struct adb_request *req)
47{
48 complete((struct completion *)req->arg);
49}
50
51/* Only call this function from task context */
52static void ams_pmu_set_register(u8 reg, u8 value)
53{
54 static struct adb_request req;
55 DECLARE_COMPLETION(req_complete);
56
57 req.arg = &req_complete;
58 if (pmu_request(&req, ams_pmu_req_complete, 4, ams_pmu_cmd, 0x00, reg, value))
59 return;
60
61 wait_for_completion(&req_complete);
62}
63
64/* Only call this function from task context */
65static u8 ams_pmu_get_register(u8 reg)
66{
67 static struct adb_request req;
68 DECLARE_COMPLETION(req_complete);
69
70 req.arg = &req_complete;
71 if (pmu_request(&req, ams_pmu_req_complete, 3, ams_pmu_cmd, 0x01, reg))
72 return 0;
73
74 wait_for_completion(&req_complete);
75
76 if (req.reply_len > 0)
77 return req.reply[0];
78 else
79 return 0;
80}
81
82/* Enables or disables the specified interrupts */
83static void ams_pmu_set_irq(enum ams_irq reg, char enable)
84{
85 if (reg & AMS_IRQ_FREEFALL) {
86 u8 val = ams_pmu_get_register(AMS_FF_ENABLE);
87 if (enable)
88 val |= 0x80;
89 else
90 val &= ~0x80;
91 ams_pmu_set_register(AMS_FF_ENABLE, val);
92 }
93
94 if (reg & AMS_IRQ_SHOCK) {
95 u8 val = ams_pmu_get_register(AMS_SHOCK_ENABLE);
96 if (enable)
97 val |= 0x80;
98 else
99 val &= ~0x80;
100 ams_pmu_set_register(AMS_SHOCK_ENABLE, val);
101 }
102
103 if (reg & AMS_IRQ_GLOBAL) {
104 u8 val = ams_pmu_get_register(AMS_CONTROL);
105 if (enable)
106 val |= 0x80;
107 else
108 val &= ~0x80;
109 ams_pmu_set_register(AMS_CONTROL, val);
110 }
111}
112
113static void ams_pmu_clear_irq(enum ams_irq reg)
114{
115 if (reg & AMS_IRQ_FREEFALL)
116 ams_pmu_set_register(AMS_FF_CLEAR, 0x00);
117
118 if (reg & AMS_IRQ_SHOCK)
119 ams_pmu_set_register(AMS_SHOCK_CLEAR, 0x00);
120}
121
122static u8 ams_pmu_get_vendor(void)
123{
124 return ams_pmu_get_register(AMS_VENDOR);
125}
126
127static void ams_pmu_get_xyz(s8 *x, s8 *y, s8 *z)
128{
129 *x = ams_pmu_get_register(AMS_X);
130 *y = ams_pmu_get_register(AMS_Y);
131 *z = ams_pmu_get_register(AMS_Z);
132}
133
134static void ams_pmu_exit(void)
135{
136 /* Disable interrupts */
137 ams_pmu_set_irq(AMS_IRQ_ALL, 0);
138
139 /* Clear interrupts */
140 ams_pmu_clear_irq(AMS_IRQ_ALL);
141
142 ams_info.has_device = 0;
143
144 printk(KERN_INFO "ams: Unloading\n");
145}
146
147int __init ams_pmu_init(struct device_node *np)
148{
Stephen Rothwella7edd0e2007-04-03 10:52:17 +1000149 const u32 *prop;
Stelian Popdcb69dd2006-12-12 18:18:30 +0100150 int result;
151
152 mutex_lock(&ams_info.lock);
153
154 /* Set implementation stuff */
155 ams_info.of_node = np;
156 ams_info.exit = ams_pmu_exit;
157 ams_info.get_vendor = ams_pmu_get_vendor;
158 ams_info.get_xyz = ams_pmu_get_xyz;
159 ams_info.clear_irq = ams_pmu_clear_irq;
160 ams_info.bustype = BUS_HOST;
161
162 /* Get PMU command, should be 0x4e, but we can never know */
Stephen Rothwell40cd3a42007-05-01 13:54:02 +1000163 prop = of_get_property(ams_info.of_node, "reg", NULL);
Stelian Popdcb69dd2006-12-12 18:18:30 +0100164 if (!prop) {
165 result = -ENODEV;
166 goto exit;
167 }
168 ams_pmu_cmd = ((*prop) >> 8) & 0xff;
169
170 /* Disable interrupts */
171 ams_pmu_set_irq(AMS_IRQ_ALL, 0);
172
173 /* Clear interrupts */
174 ams_pmu_clear_irq(AMS_IRQ_ALL);
175
176 result = ams_sensor_attach();
177 if (result < 0)
178 goto exit;
179
180 /* Set default values */
181 ams_pmu_set_register(AMS_FF_LOW_LIMIT, 0x15);
182 ams_pmu_set_register(AMS_FF_ENABLE, 0x08);
183 ams_pmu_set_register(AMS_FF_DEBOUNCE, 0x14);
184
185 ams_pmu_set_register(AMS_SHOCK_HIGH_LIMIT, 0x60);
186 ams_pmu_set_register(AMS_SHOCK_ENABLE, 0x0f);
187 ams_pmu_set_register(AMS_SHOCK_DEBOUNCE, 0x14);
188
189 ams_pmu_set_register(AMS_CONTROL, 0x4f);
190
191 /* Clear interrupts */
192 ams_pmu_clear_irq(AMS_IRQ_ALL);
193
194 ams_info.has_device = 1;
195
196 /* Enable interrupts */
197 ams_pmu_set_irq(AMS_IRQ_ALL, 1);
198
199 printk(KERN_INFO "ams: Found PMU based motion sensor\n");
200
201 result = 0;
202
203exit:
204 mutex_unlock(&ams_info.lock);
205
206 return result;
207}