diff options
Diffstat (limited to 'drivers/hwmon/ams/ams-pmu.c')
| -rw-r--r-- | drivers/hwmon/ams/ams-pmu.c | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/drivers/hwmon/ams/ams-pmu.c b/drivers/hwmon/ams/ams-pmu.c new file mode 100644 index 00000000000..4636ae031a5 --- /dev/null +++ b/drivers/hwmon/ams/ams-pmu.c @@ -0,0 +1,207 @@ +/* + * Apple Motion Sensor driver (PMU variant) + * + * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/adb.h> +#include <linux/pmu.h> + +#include "ams.h" + +/* Attitude */ +#define AMS_X 0x00 +#define AMS_Y 0x01 +#define AMS_Z 0x02 + +/* Not exactly known, maybe chip vendor */ +#define AMS_VENDOR 0x03 + +/* Freefall registers */ +#define AMS_FF_CLEAR 0x04 +#define AMS_FF_ENABLE 0x05 +#define AMS_FF_LOW_LIMIT 0x06 +#define AMS_FF_DEBOUNCE 0x07 + +/* Shock registers */ +#define AMS_SHOCK_CLEAR 0x08 +#define AMS_SHOCK_ENABLE 0x09 +#define AMS_SHOCK_HIGH_LIMIT 0x0a +#define AMS_SHOCK_DEBOUNCE 0x0b + +/* Global interrupt and power control register */ +#define AMS_CONTROL 0x0c + +static u8 ams_pmu_cmd; + +static void ams_pmu_req_complete(struct adb_request *req) +{ + complete((struct completion *)req->arg); +} + +/* Only call this function from task context */ +static void ams_pmu_set_register(u8 reg, u8 value) +{ + static struct adb_request req; + DECLARE_COMPLETION(req_complete); + + req.arg = &req_complete; + if (pmu_request(&req, ams_pmu_req_complete, 4, ams_pmu_cmd, 0x00, reg, value)) + return; + + wait_for_completion(&req_complete); +} + +/* Only call this function from task context */ +static u8 ams_pmu_get_register(u8 reg) +{ + static struct adb_request req; + DECLARE_COMPLETION(req_complete); + + req.arg = &req_complete; + if (pmu_request(&req, ams_pmu_req_complete, 3, ams_pmu_cmd, 0x01, reg)) + return 0; + + wait_for_completion(&req_complete); + + if (req.reply_len > 0) + return req.reply[0]; + else + return 0; +} + +/* Enables or disables the specified interrupts */ +static void ams_pmu_set_irq(enum ams_irq reg, char enable) +{ + if (reg & AMS_IRQ_FREEFALL) { + u8 val = ams_pmu_get_register(AMS_FF_ENABLE); + if (enable) + val |= 0x80; + else + val &= ~0x80; + ams_pmu_set_register(AMS_FF_ENABLE, val); + } + + if (reg & AMS_IRQ_SHOCK) { + u8 val = ams_pmu_get_register(AMS_SHOCK_ENABLE); + if (enable) + val |= 0x80; + else + val &= ~0x80; + ams_pmu_set_register(AMS_SHOCK_ENABLE, val); + } + + if (reg & AMS_IRQ_GLOBAL) { + u8 val = ams_pmu_get_register(AMS_CONTROL); + if (enable) + val |= 0x80; + else + val &= ~0x80; + ams_pmu_set_register(AMS_CONTROL, val); + } +} + +static void ams_pmu_clear_irq(enum ams_irq reg) +{ + if (reg & AMS_IRQ_FREEFALL) + ams_pmu_set_register(AMS_FF_CLEAR, 0x00); + + if (reg & AMS_IRQ_SHOCK) + ams_pmu_set_register(AMS_SHOCK_CLEAR, 0x00); +} + +static u8 ams_pmu_get_vendor(void) +{ + return ams_pmu_get_register(AMS_VENDOR); +} + +static void ams_pmu_get_xyz(s8 *x, s8 *y, s8 *z) +{ + *x = ams_pmu_get_register(AMS_X); + *y = ams_pmu_get_register(AMS_Y); + *z = ams_pmu_get_register(AMS_Z); +} + +static void ams_pmu_exit(void) +{ + /* Disable interrupts */ + ams_pmu_set_irq(AMS_IRQ_ALL, 0); + + /* Clear interrupts */ + ams_pmu_clear_irq(AMS_IRQ_ALL); + + ams_info.has_device = 0; + + printk(KERN_INFO "ams: Unloading\n"); +} + +int __init ams_pmu_init(struct device_node *np) +{ + u32 *prop; + int result; + + mutex_lock(&ams_info.lock); + + /* Set implementation stuff */ + ams_info.of_node = np; + ams_info.exit = ams_pmu_exit; + ams_info.get_vendor = ams_pmu_get_vendor; + ams_info.get_xyz = ams_pmu_get_xyz; + ams_info.clear_irq = ams_pmu_clear_irq; + ams_info.bustype = BUS_HOST; + + /* Get PMU command, should be 0x4e, but we can never know */ + prop = (u32*)get_property(ams_info.of_node, "reg", NULL); + if (!prop) { + result = -ENODEV; + goto exit; + } + ams_pmu_cmd = ((*prop) >> 8) & 0xff; + + /* Disable interrupts */ + ams_pmu_set_irq(AMS_IRQ_ALL, 0); + + /* Clear interrupts */ + ams_pmu_clear_irq(AMS_IRQ_ALL); + + result = ams_sensor_attach(); + if (result < 0) + goto exit; + + /* Set default values */ + ams_pmu_set_register(AMS_FF_LOW_LIMIT, 0x15); + ams_pmu_set_register(AMS_FF_ENABLE, 0x08); + ams_pmu_set_register(AMS_FF_DEBOUNCE, 0x14); + + ams_pmu_set_register(AMS_SHOCK_HIGH_LIMIT, 0x60); + ams_pmu_set_register(AMS_SHOCK_ENABLE, 0x0f); + ams_pmu_set_register(AMS_SHOCK_DEBOUNCE, 0x14); + + ams_pmu_set_register(AMS_CONTROL, 0x4f); + + /* Clear interrupts */ + ams_pmu_clear_irq(AMS_IRQ_ALL); + + ams_info.has_device = 1; + + /* Enable interrupts */ + ams_pmu_set_irq(AMS_IRQ_ALL, 1); + + printk(KERN_INFO "ams: Found PMU based motion sensor\n"); + + result = 0; + +exit: + mutex_unlock(&ams_info.lock); + + return result; +} |