• Petr Vandrovec's avatar
    [PATCH] hwmon: Fix w83627ehf/hf vs PNPACPI conflict (bug #4014) · ada0c2f8
    Petr Vandrovec authored
    This patch changes w83627hf and w83627ehf drivers to reserve only ports
    0x295-0x296, instead of full 0x290-0x297 range.  While some other
    sensors chips respond to all addresses in 0x290-0x297 range, Winbond
    chips respond to 0x295-0x296 only (this behavior is implied by
    documentation, and matches behavior observed on real systems).  This is
    not problem alone, as no BIOS was found to put something at these unused
    addresses, and sensors chip itself provides nothing there as well.
    
    But in addition to only respond to these two addresses, also BIOS
    vendors report in their ACPI-PnP structures that there is some resource
    at I/O address 0x295 of length 2.  And when later this hwmon driver
    attempts to request region with base 0x290/length 8, it fails as one
    request_region cannot span more than one device.
    
    Due to this we have to ask only for region this hardware really
    occupies, otherwise driver cannot be loaded on systems with ACPI-PnP
    enabled.
    Signed-off-by: default avatarPetr Vandrovec <vandrove@vc.cvut.cz>
    Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
    ada0c2f8
w83627hf.c 44 KB