--- /dev/null
+/*
+ * 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",
+ .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");
Code Review / kvmfornfv.git / blobdiff