From: Rudolf Marek Content-Disposition: inline; filename=hwmon-w83627ehf-fix-fan5-detection.patch Fix the detection of fan5 and preserve the bit between the register writes, because the bit is write only. Signed-off-by: Rudolf Marek Signed-off-by: Jean Delvare --- drivers/hwmon/w83627ehf.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) --- linux-2.6.19-rc1.orig/drivers/hwmon/w83627ehf.c 2006-10-08 12:29:27.000000000 +0200 +++ linux-2.6.19-rc1/drivers/hwmon/w83627ehf.c 2006-10-08 12:39:24.000000000 +0200 @@ -354,6 +354,8 @@ case 0: reg = (w83627ehf_read_value(client, W83627EHF_REG_FANDIV1) & 0xcf) | ((data->fan_div[0] & 0x03) << 4); + /* fan5 input control bit is write only, compute the value */ + reg |= (data->has_fan & (1 << 4)) ? 1 : 0; w83627ehf_write_value(client, W83627EHF_REG_FANDIV1, reg); reg = (w83627ehf_read_value(client, W83627EHF_REG_VBAT) & 0xdf) | ((data->fan_div[0] & 0x04) << 3); @@ -362,6 +364,8 @@ case 1: reg = (w83627ehf_read_value(client, W83627EHF_REG_FANDIV1) & 0x3f) | ((data->fan_div[1] & 0x03) << 6); + /* fan5 input control bit is write only, compute the value */ + reg |= (data->has_fan & (1 << 4)) ? 1 : 0; w83627ehf_write_value(client, W83627EHF_REG_FANDIV1, reg); reg = (w83627ehf_read_value(client, W83627EHF_REG_VBAT) & 0xbf) | ((data->fan_div[1] & 0x04) << 4); @@ -1216,13 +1220,16 @@ superio_exit(); /* It looks like fan4 and fan5 pins can be alternatively used - as fan on/off switches */ + as fan on/off switches, but fan5 control is write only :/ + We assume that if the serial interface is disabled, designers + connected fan5 as input unless they are emitting log 1, which + is not the default. */ data->has_fan = 0x07; /* fan1, fan2 and fan3 */ i = w83627ehf_read_value(client, W83627EHF_REG_FANDIV1); if ((i & (1 << 2)) && (!fan4pin)) data->has_fan |= (1 << 3); - if ((i & (1 << 0)) && (!fan5pin)) + if (!(i & (1 << 1)) && (!fan5pin)) data->has_fan |= (1 << 4); /* Register sysfs hooks */