- /* NB: page 240 of ICH5 datasheet shows that the R/#W
- * bit should be cleared here, even when reading */
- outb_p((addr & 0x7f) << 1, SMBHSTADD(priv));
+ /*
+ * NB: page 240 of ICH5 datasheet shows that the R/#W
+ * bit should be cleared here, even when reading.
+ * However if SPD Write Disable is set (Lynx Point and later),
+ * the read will fail if we don't set the R/#W bit.
+ */
+ outb_p(((addr & 0x7f) << 1) |
+ ((priv->original_hstcfg & SMBHSTCFG_SPD_WD) ?
+ (read_write & 0x01) : 0),
+ SMBHSTADD(priv));