diff --git a/Documentation/hwmon/via686a b/Documentation/hwmon/via686a index b82014cb7c53..a936fb3824b2 100644 --- a/Documentation/hwmon/via686a +++ b/Documentation/hwmon/via686a @@ -18,8 +18,9 @@ Authors: Module Parameters ----------------- -force_addr=0xaddr Set the I/O base address. Useful for Asus A7V boards - that don't set the address in the BIOS. Does not do a +force_addr=0xaddr Set the I/O base address. Useful for boards that + don't set the address in the BIOS. Look for a BIOS + upgrade before resorting to this. Does not do a PCI force; the via686a must still be present in lspci. Don't use this unless the driver complains that the base address is not set. @@ -63,3 +64,15 @@ miss once-only alarms. The driver only updates its values each 1.5 seconds; reading it more often will do no harm, but will return 'old' values. + +Known Issues +------------ + +This driver handles sensors integrated in some VIA south bridges. It is +possible that a motherboard maker used a VT82C686A/B chip as part of a +product design but was not interested in its hardware monitoring features, +in which case the sensor inputs will not be wired. This is the case of +the Asus K7V, A7V and A7V133 motherboards, to name only a few of them. +So, if you need the force_addr parameter, and end up with values which +don't seem to make any sense, don't look any further: your chip is simply +not wired for hardware monitoring. diff --git a/drivers/hwmon/via686a.c b/drivers/hwmon/via686a.c index 60e94879f415..688ccf924c3a 100644 --- a/drivers/hwmon/via686a.c +++ b/drivers/hwmon/via686a.c @@ -589,10 +589,8 @@ static int via686a_detect(struct i2c_adapter *adapter) u16 val; /* 8231 requires multiple of 256, we enforce that on 686 as well */ - if (force_addr) - address = force_addr & 0xFF00; - if (force_addr) { + address = force_addr & 0xFF00; dev_warn(&adapter->dev, "forcing ISA address 0x%04X\n", address); if (PCIBIOS_SUCCESSFUL != @@ -603,11 +601,17 @@ static int via686a_detect(struct i2c_adapter *adapter) pci_read_config_word(s_bridge, VIA686A_ENABLE_REG, &val)) return -ENODEV; if (!(val & 0x0001)) { - dev_warn(&adapter->dev, "enabling sensors\n"); - if (PCIBIOS_SUCCESSFUL != - pci_write_config_word(s_bridge, VIA686A_ENABLE_REG, - val | 0x0001)) + if (force_addr) { + dev_info(&adapter->dev, "enabling sensors\n"); + if (PCIBIOS_SUCCESSFUL != + pci_write_config_word(s_bridge, VIA686A_ENABLE_REG, + val | 0x0001)) + return -ENODEV; + } else { + dev_warn(&adapter->dev, "sensors disabled - enable " + "with force_addr=0x%x\n", address); return -ENODEV; + } } /* Reserve the ISA region */