1 /* 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 44 static u8 ams_pmu_cmd; 45 46 static 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 */ 52 static 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 */ 65 static 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 */ 83 static 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 } 112 113 static 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 } 121 122 static u8 ams_pmu_get_vendor(void) 123 { 124 return ams_pmu_get_register(AMS_VENDOR); 125 } 126 127 static 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 } 133 134 static void ams_pmu_exit(void) 135 { 136 ams_sensor_detach(); 137 138 /* Disable interrupts */ 139 ams_pmu_set_irq(AMS_IRQ_ALL, 0); 140 141 /* Clear interrupts */ 142 ams_pmu_clear_irq(AMS_IRQ_ALL); 143 144 ams_info.has_device = 0; 145 146 printk(KERN_INFO "ams: Unloading\n"); 147 } 148 149 int __init ams_pmu_init(struct device_node *np) 150 { 151 const u32 *prop; 152 int result; 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 */ 163 prop = of_get_property(ams_info.of_node, "reg", NULL); 164 if (!prop) 165 return -ENODEV; 166 167 ams_pmu_cmd = ((*prop) >> 8) & 0xff; 168 169 /* Disable interrupts */ 170 ams_pmu_set_irq(AMS_IRQ_ALL, 0); 171 172 /* Clear interrupts */ 173 ams_pmu_clear_irq(AMS_IRQ_ALL); 174 175 result = ams_sensor_attach(); 176 if (result < 0) 177 return result; 178 179 /* Set default values */ 180 ams_pmu_set_register(AMS_FF_LOW_LIMIT, 0x15); 181 ams_pmu_set_register(AMS_FF_ENABLE, 0x08); 182 ams_pmu_set_register(AMS_FF_DEBOUNCE, 0x14); 183 184 ams_pmu_set_register(AMS_SHOCK_HIGH_LIMIT, 0x60); 185 ams_pmu_set_register(AMS_SHOCK_ENABLE, 0x0f); 186 ams_pmu_set_register(AMS_SHOCK_DEBOUNCE, 0x14); 187 188 ams_pmu_set_register(AMS_CONTROL, 0x4f); 189 190 /* Clear interrupts */ 191 ams_pmu_clear_irq(AMS_IRQ_ALL); 192 193 ams_info.has_device = 1; 194 195 /* Enable interrupts */ 196 ams_pmu_set_irq(AMS_IRQ_ALL, 1); 197 198 printk(KERN_INFO "ams: Found PMU based motion sensor\n"); 199 200 return 0; 201 } 202