cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

ams-pmu.c (4282B)

      1// SPDX-License-Identifier: GPL-2.0-or-later
      2/*
      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			0x00
     19#define AMS_Y			0x01
     20#define AMS_Z			0x02
     21
     22/* Not exactly known, maybe chip vendor */
     23#define AMS_VENDOR		0x03
     24
     25/* Freefall registers */
     26#define AMS_FF_CLEAR		0x04
     27#define AMS_FF_ENABLE		0x05
     28#define AMS_FF_LOW_LIMIT	0x06
     29#define AMS_FF_DEBOUNCE		0x07
     30
     31/* Shock registers */
     32#define AMS_SHOCK_CLEAR		0x08
     33#define AMS_SHOCK_ENABLE	0x09
     34#define AMS_SHOCK_HIGH_LIMIT	0x0a
     35#define AMS_SHOCK_DEBOUNCE	0x0b
     36
     37/* Global interrupt and power control register */
     38#define AMS_CONTROL		0x0c
     39
     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	else
     75		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		else
     86			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		else
     95			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		else
    104			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}