198 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Apple Motion Sensor driver (PMU variant)4 *5 * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)6 */7 8#include <linux/module.h>9#include <linux/types.h>10#include <linux/errno.h>11#include <linux/init.h>12#include <linux/adb.h>13#include <linux/pmu.h>14 15#include "ams.h"16 17/* Attitude */18#define AMS_X 0x0019#define AMS_Y 0x0120#define AMS_Z 0x0221 22/* Not exactly known, maybe chip vendor */23#define AMS_VENDOR 0x0324 25/* Freefall registers */26#define AMS_FF_CLEAR 0x0427#define AMS_FF_ENABLE 0x0528#define AMS_FF_LOW_LIMIT 0x0629#define AMS_FF_DEBOUNCE 0x0730 31/* Shock registers */32#define AMS_SHOCK_CLEAR 0x0833#define AMS_SHOCK_ENABLE 0x0934#define AMS_SHOCK_HIGH_LIMIT 0x0a35#define AMS_SHOCK_DEBOUNCE 0x0b36 37/* Global interrupt and power control register */38#define AMS_CONTROL 0x0c39 40static u8 ams_pmu_cmd;41 42static void ams_pmu_req_complete(struct adb_request *req)43{44 complete((struct completion *)req->arg);45}46 47/* Only call this function from task context */48static void ams_pmu_set_register(u8 reg, u8 value)49{50 static struct adb_request req;51 DECLARE_COMPLETION(req_complete);52 53 req.arg = &req_complete;54 if (pmu_request(&req, ams_pmu_req_complete, 4, ams_pmu_cmd, 0x00, reg, value))55 return;56 57 wait_for_completion(&req_complete);58}59 60/* Only call this function from task context */61static u8 ams_pmu_get_register(u8 reg)62{63 static struct adb_request req;64 DECLARE_COMPLETION(req_complete);65 66 req.arg = &req_complete;67 if (pmu_request(&req, ams_pmu_req_complete, 3, ams_pmu_cmd, 0x01, reg))68 return 0;69 70 wait_for_completion(&req_complete);71 72 if (req.reply_len > 0)73 return req.reply[0];74 else75 return 0;76}77 78/* Enables or disables the specified interrupts */79static void ams_pmu_set_irq(enum ams_irq reg, char enable)80{81 if (reg & AMS_IRQ_FREEFALL) {82 u8 val = ams_pmu_get_register(AMS_FF_ENABLE);83 if (enable)84 val |= 0x80;85 else86 val &= ~0x80;87 ams_pmu_set_register(AMS_FF_ENABLE, val);88 }89 90 if (reg & AMS_IRQ_SHOCK) {91 u8 val = ams_pmu_get_register(AMS_SHOCK_ENABLE);92 if (enable)93 val |= 0x80;94 else95 val &= ~0x80;96 ams_pmu_set_register(AMS_SHOCK_ENABLE, val);97 }98 99 if (reg & AMS_IRQ_GLOBAL) {100 u8 val = ams_pmu_get_register(AMS_CONTROL);101 if (enable)102 val |= 0x80;103 else104 val &= ~0x80;105 ams_pmu_set_register(AMS_CONTROL, val);106 }107}108 109static void ams_pmu_clear_irq(enum ams_irq reg)110{111 if (reg & AMS_IRQ_FREEFALL)112 ams_pmu_set_register(AMS_FF_CLEAR, 0x00);113 114 if (reg & AMS_IRQ_SHOCK)115 ams_pmu_set_register(AMS_SHOCK_CLEAR, 0x00);116}117 118static u8 ams_pmu_get_vendor(void)119{120 return ams_pmu_get_register(AMS_VENDOR);121}122 123static void ams_pmu_get_xyz(s8 *x, s8 *y, s8 *z)124{125 *x = ams_pmu_get_register(AMS_X);126 *y = ams_pmu_get_register(AMS_Y);127 *z = ams_pmu_get_register(AMS_Z);128}129 130static void ams_pmu_exit(void)131{132 ams_sensor_detach();133 134 /* Disable interrupts */135 ams_pmu_set_irq(AMS_IRQ_ALL, 0);136 137 /* Clear interrupts */138 ams_pmu_clear_irq(AMS_IRQ_ALL);139 140 ams_info.has_device = 0;141 142 printk(KERN_INFO "ams: Unloading\n");143}144 145int __init ams_pmu_init(struct device_node *np)146{147 const u32 *prop;148 int result;149 150 /* Set implementation stuff */151 ams_info.of_node = np;152 ams_info.exit = ams_pmu_exit;153 ams_info.get_vendor = ams_pmu_get_vendor;154 ams_info.get_xyz = ams_pmu_get_xyz;155 ams_info.clear_irq = ams_pmu_clear_irq;156 ams_info.bustype = BUS_HOST;157 158 /* Get PMU command, should be 0x4e, but we can never know */159 prop = of_get_property(ams_info.of_node, "reg", NULL);160 if (!prop)161 return -ENODEV;162 163 ams_pmu_cmd = ((*prop) >> 8) & 0xff;164 165 /* Disable interrupts */166 ams_pmu_set_irq(AMS_IRQ_ALL, 0);167 168 /* Clear interrupts */169 ams_pmu_clear_irq(AMS_IRQ_ALL);170 171 result = ams_sensor_attach();172 if (result < 0)173 return result;174 175 /* Set default values */176 ams_pmu_set_register(AMS_FF_LOW_LIMIT, 0x15);177 ams_pmu_set_register(AMS_FF_ENABLE, 0x08);178 ams_pmu_set_register(AMS_FF_DEBOUNCE, 0x14);179 180 ams_pmu_set_register(AMS_SHOCK_HIGH_LIMIT, 0x60);181 ams_pmu_set_register(AMS_SHOCK_ENABLE, 0x0f);182 ams_pmu_set_register(AMS_SHOCK_DEBOUNCE, 0x14);183 184 ams_pmu_set_register(AMS_CONTROL, 0x4f);185 186 /* Clear interrupts */187 ams_pmu_clear_irq(AMS_IRQ_ALL);188 189 ams_info.has_device = 1;190 191 /* Enable interrupts */192 ams_pmu_set_irq(AMS_IRQ_ALL, 1);193 194 printk(KERN_INFO "ams: Found PMU based motion sensor\n");195 196 return 0;197}198