/* * Creation Date: <2003/03/14 20:54:13 samuel> * Time-stamp: <2004/03/20 14:20:59 samuel> * * <therm_windtunnel.c> * * The G4 "windtunnel" has a single fan controlled by an * ADM1030 fan controller and a DS1775 thermostat. * * The fan controller is equipped with a temperature sensor * which measures the case temperature. The DS1775 sensor * measures the CPU temperature. This driver tunes the * behavior of the fan. It is based upon empirical observations * of the 'AppleFan' driver under Mac OS X. * * WARNING: This driver has only been testen on Apple's * 1.25 MHz Dual G4 (March 03). It is tuned for a CPU * temperature around 57 C. * * Copyright (C) 2003, 2004 Samuel Rydh (samuel@ibrium.se) * * Loosely based upon 'thermostat.c' written by Benjamin Herrenschmidt * * 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 * */ #include <linux/types.h> #include <linux/module.h> #include <linux/errno.h> #include <linux/kernel.h> #include <linux/delay.h> #include <linux/sched.h> #include <linux/i2c.h> #include <linux/init.h> #include <linux/kthread.h> #include <linux/of_platform.h> #include <asm/prom.h> #include <asm/machdep.h> #include <asm/io.h> #include <asm/sections.h> #include <asm/macio.h> #define LOG_TEMP 0 /* continuously log temperature */ static struct { volatile int running; struct task_struct *poll_task; struct mutex lock; struct platform_device *of_dev; struct i2c_client *thermostat; struct i2c_client *fan; int overheat_temp; /* 100% fan at this temp */ int overheat_hyst; int temp; int casetemp; int fan_level; /* active fan_table setting */ int downind; int upind; int r0, r1, r20, r23, r25; /* saved register */ } x; #define T(x,y) (((x)<<8) | (y)*0x100/10 ) static struct { int fan_down_setting; int temp; int fan_up_setting; } fan_table[] = { { 11, T(0,0), 11 }, /* min fan */ { 11, T(55,0), 11 }, { 6, T(55,3), 11 }, { 7, T(56,0), 11 }, { 8, T(57,0), 8 }, { 7, T(58,3), 7 }, { 6, T(58,8), 6 }, { 5, T(59,2), 5 }, { 4, T(59,6), 4 }, { 3, T(59,9), 3 }, { 2, T(60,1), 2 }, { 1, 0xfffff, 1 } /* on fire */ }; static void print_temp( const char *s, int temp ) { printk("%s%d.%d C", s ? s : "", temp>>8, (temp & 255)*10/256 ); } static ssize_t show_cpu_temperature( struct device *dev, struct device_attribute *attr, char *buf ) { return sprintf(buf, "%d.%d\n", x.temp>>8, (x.temp & 255)*10/256 ); } static ssize_t show_case_temperature( struct device *dev, struct device_attribute *attr, char *buf ) { return sprintf(buf, "%d.%d\n", x.casetemp>>8, (x.casetemp & 255)*10/256 ); } static DEVICE_ATTR(cpu_temperature, S_IRUGO, show_cpu_temperature, NULL ); static DEVICE_ATTR(case_temperature, S_IRUGO, show_case_temperature, NULL ); /************************************************************************/ /* controller thread */ /************************************************************************/ static int write_reg( struct i2c_client *cl, int reg, int data, int len ) { u8 tmp[3]; if( len < 1 || len > 2 || data < 0 ) return -EINVAL; tmp[0] = reg; tmp[1] = (len == 1) ? data : (data >> 8); tmp[2] = data; len++; if( i2c_master_send(cl, tmp, len) != len ) return -ENODEV; return 0; } static int read_reg( struct i2c_client *cl, int reg, int len ) { u8 buf[2]; if( len != 1 && len != 2 ) return -EINVAL; buf[0] = reg; if( i2c_master_send(cl, buf, 1) != 1 ) return -ENODEV; if( i2c_master_recv(cl, buf, len) != len ) return -ENODEV; return (len == 2)? ((unsigned int)buf[0] << 8) | buf[1] : buf[0]; } static void tune_fan( int fan_setting ) { int val = (fan_setting << 3) | 7; /* write_reg( x.fan, 0x24, val, 1 ); */ write_reg( x.fan, 0x25, val, 1 ); write_reg( x.fan, 0x20, 0, 1 ); print_temp("CPU-temp: ", x.temp ); if( x.casetemp ) print_temp(", Case: ", x.casetemp ); printk(", Fan: %d (tuned %+d)\n", 11-fan_setting, x.fan_level-fan_setting ); x.fan_level = fan_setting; } static void poll_temp( void ) { int temp, i, level, casetemp; temp = read_reg( x.thermostat, 0, 2 ); /* this actually occurs when the computer is loaded */ if( temp < 0 ) return; casetemp = read_reg(x.fan, 0x0b, 1) << 8; casetemp |= (read_reg(x.fan, 0x06, 1) & 0x7) << 5; if( LOG_TEMP && x.temp != temp ) { print_temp("CPU-temp: ", temp ); print_temp(", Case: ", casetemp ); printk(", Fan: %d\n", 11-x.fan_level ); } x.temp = temp; x.casetemp = casetemp; level = -1; for( i=0; (temp & 0xffff) > fan_table[i].temp ; i++ ) ; if( i < x.downind ) level = fan_table[i].fan_down_setting; x.downind = i; for( i=0; (temp & 0xffff) >= fan_table[i+1].temp ; i++ ) ; if( x.upind < i ) level = fan_table[i].fan_up_setting; x.upind = i; if( level >= 0 ) tune_fan( level ); } static void setup_hardware( void ) { int val; int err; /* save registers (if we unload the module) */ x.r0 = read_reg( x.fan, 0x00, 1 ); x.r1 = read_reg( x.fan, 0x01, 1 ); x.r20 = read_reg( x.fan, 0x20, 1 ); x.r23 = read_reg( x.fan, 0x23, 1 ); x.r25 = read_reg( x.fan, 0x25, 1 ); /* improve measurement resolution (convergence time 1.5s) */ if( (val=read_reg(x.thermostat, 1, 1)) >= 0 ) { val |= 0x60; if( write_reg( x.thermostat, 1, val, 1 ) ) printk("Failed writing config register\n"); } /* disable interrupts and TAC input */ write_reg( x.fan, 0x01, 0x01, 1 ); /* enable filter */ write_reg( x.fan, 0x23, 0x91, 1 ); /* remote temp. controls fan */ write_reg( x.fan, 0x00, 0x95, 1 ); /* The thermostat (which besides measureing temperature controls * has a THERM output which puts the fan on 100%) is usually * set to kick in at 80 C (chip default). We reduce this a bit * to be on the safe side (OSX doesn't)... */ if( x.overheat_temp == (80 << 8) ) { x.overheat_temp = 75 << 8; x.overheat_hyst = 70 << 8; write_reg( x.thermostat, 2, x.overheat_hyst, 2 ); write_reg( x.thermostat, 3, x.overheat_temp, 2 ); print_temp("Reducing overheating limit to ", x.overheat_temp ); print_temp(" (Hyst: ", x.overheat_hyst ); printk(")\n"); } /* set an initial fan setting */ x.downind = 0xffff; x.upind = -1; /* tune_fan( fan_up_table[x.upind].fan_setting ); */ err = device_create_file( &x.of_dev->dev, &dev_attr_cpu_temperature ); err |= device_create_file( &x.of_dev->dev, &dev_attr_case_temperature ); if (err) printk(KERN_WARNING "Failed to create temperature attribute file(s).\n"); } static void restore_regs( void ) { device_remove_file( &x.of_dev->dev, &dev_attr_cpu_temperature ); device_remove_file( &x.of_dev->dev, &dev_attr_case_temperature ); write_reg( x.fan, 0x01, x.r1, 1 ); write_reg( x.fan, 0x20, x.r20, 1 ); write_reg( x.fan, 0x23, x.r23, 1 ); write_reg( x.fan, 0x25, x.r25, 1 ); write_reg( x.fan, 0x00, x.r0, 1 ); } static int control_loop(void *dummy) { mutex_lock(&x.lock); setup_hardware(); mutex_unlock(&x.lock); for (;;) { msleep_interruptible(8000); if (kthread_should_stop()) break; mutex_lock(&x.lock); poll_temp(); mutex_unlock(&x.lock); } mutex_lock(&x.lock); restore_regs(); mutex_unlock(&x.lock); return 0; } /************************************************************************/ /* i2c probing and setup */ /************************************************************************/ static int do_attach( struct i2c_adapter *adapter ) { /* scan 0x48-0x4f (DS1775) and 0x2c-2x2f (ADM1030) */ static const unsigned short scan_ds1775[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, I2C_CLIENT_END }; static const unsigned short scan_adm1030[] = { 0x2c, 0x2d, 0x2e, 0x2f, I2C_CLIENT_END }; if( strncmp(adapter->name, "uni-n", 5) ) return 0; if( !x.running ) { struct i2c_board_info info; memset(&info, 0, sizeof(struct i2c_board_info)); strlcpy(info.type, "therm_ds1775", I2C_NAME_SIZE); i2c_new_probed_device(adapter, &info, scan_ds1775, NULL); strlcpy(info.type, "therm_adm1030", I2C_NAME_SIZE); i2c_new_probed_device(adapter, &info, scan_adm1030, NULL); if( x.thermostat && x.fan ) { x.running = 1; x.poll_task = kthread_run(control_loop, NULL, "g4fand"); } } return 0; } static int do_remove(struct i2c_client *client) { if (x.running) { x.running = 0; kthread_stop(x.poll_task); x.poll_task = NULL; } if (client == x.thermostat) x.thermostat = NULL; else if (client == x.fan) x.fan = NULL; else printk(KERN_ERR "g4fan: bad client\n"); return 0; } static int attach_fan( struct i2c_client *cl ) { if( x.fan ) goto out; /* check that this is an ADM1030 */ if( read_reg(cl, 0x3d, 1) != 0x30 || read_reg(cl, 0x3e, 1) != 0x41 ) goto out; printk("ADM1030 fan controller [@%02x]\n", cl->addr ); x.fan = cl; out: return 0; } static int attach_thermostat( struct i2c_client *cl ) { int hyst_temp, os_temp, temp; if( x.thermostat ) goto out; if( (temp=read_reg(cl, 0, 2)) < 0 ) goto out; /* temperature sanity check */ if( temp < 0x1600 || temp > 0x3c00 ) goto out; hyst_temp = read_reg(cl, 2, 2); os_temp = read_reg(cl, 3, 2); if( hyst_temp < 0 || os_temp < 0 ) goto out; printk("DS1775 digital thermometer [@%02x]\n", cl->addr ); print_temp("Temp: ", temp ); print_temp(" Hyst: ", hyst_temp ); print_temp(" OS: ", os_temp ); printk("\n"); x.temp = temp; x.overheat_temp = os_temp; x.overheat_hyst = hyst_temp; x.thermostat = cl; out: return 0; } enum chip { ds1775, adm1030 }; static const struct i2c_device_id therm_windtunnel_id[] = { { "therm_ds1775", ds1775 }, { "therm_adm1030", adm1030 }, { } }; static int do_probe(struct i2c_client *cl, const struct i2c_device_id *id) { struct i2c_adapter *adapter = cl->adapter; if( !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_WRITE_BYTE) ) return 0; switch (id->driver_data) { case adm1030: return attach_fan( cl ); case ds1775: return attach_thermostat(cl); } return 0; } static struct i2c_driver g4fan_driver = { .driver = { .name = "therm_windtunnel", }, .attach_adapter = do_attach, .probe = do_probe, .remove = do_remove, .id_table = therm_windtunnel_id, }; /************************************************************************/ /* initialization / cleanup */ /************************************************************************/ static int therm_of_probe(struct platform_device *dev) { return i2c_add_driver( &g4fan_driver ); } static int therm_of_remove( struct platform_device *dev ) { i2c_del_driver( &g4fan_driver ); return 0; } static const struct of_device_id therm_of_match[] = {{ .name = "fan", .compatible = "adm1030" }, {} }; static struct platform_driver therm_of_driver = { .driver = { .name = "temperature", .owner = THIS_MODULE, .of_match_table = therm_of_match, }, .probe = therm_of_probe, .remove = therm_of_remove, }; struct apple_thermal_info { u8 id; /* implementation ID */ u8 fan_count; /* number of fans */ u8 thermostat_count; /* number of thermostats */ u8 unused; }; static int __init g4fan_init( void ) { const struct apple_thermal_info *info; struct device_node *np; mutex_init(&x.lock); if( !(np=of_find_node_by_name(NULL, "power-mgt")) ) return -ENODEV; info = of_get_property(np, "thermal-info", NULL); of_node_put(np); if( !info || !of_machine_is_compatible("PowerMac3,6") ) return -ENODEV; if( info->id != 3 ) { printk(KERN_ERR "therm_windtunnel: unsupported thermal design %d\n", info->id ); return -ENODEV; } if( !(np=of_find_node_by_name(NULL, "fan")) ) return -ENODEV; x.of_dev = of_platform_device_create(np, "temperature", NULL); of_node_put( np ); if( !x.of_dev ) { printk(KERN_ERR "Can't register fan controller!\n"); return -ENODEV; } platform_driver_register( &therm_of_driver ); return 0; } static void __exit g4fan_exit( void ) { platform_driver_unregister( &therm_of_driver ); if( x.of_dev ) of_device_unregister( x.of_dev ); } module_init(g4fan_init); module_exit(g4fan_exit); MODULE_AUTHOR("Samuel Rydh <samuel@ibrium.se>"); MODULE_DESCRIPTION("Apple G4 (windtunnel) fan controller"); MODULE_LICENSE("GPL");