The 2012 series of MacBooks have a faster SMC, and the current driver timings do not work at all. Tests show that decreasing the minimum wait time, from 64 us to 16 us, works well. Since this is still larger than the original minimum of 10 us used before 2008, there is nothing inherently problematic with changing it. The fail frequency on older machines seems to increase slightly, but not enough to be noticeable. Tested on MBA11, MBA31, MBA5,2, MBP9,2. The patch was originally written by adamski99 (ubuntuforums.org) and later tested by janhouse (bbs.archlinux.org). Signed-off-by: Henrik Rydberg <rydberg@xxxxxxxxxxx> --- Hi Guenter, This patch enables the mid-2012 MacBook models. The patch affects older models slightly, but mostly in a good way; all models get slightly faster reads, but some older models see a slight increase in read fail frequency. I do not think this will be noticeable, but I would hesitate to backport too far. For 3.6. Thanks, Henrik drivers/hwmon/applesmc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hwmon/applesmc.c b/drivers/hwmon/applesmc.c index 0162f55..f41585e 100644 --- a/drivers/hwmon/applesmc.c +++ b/drivers/hwmon/applesmc.c @@ -54,7 +54,7 @@ #define APPLESMC_MAX_DATA_LENGTH 32 /* wait up to 32 ms for a status change. */ -#define APPLESMC_MIN_WAIT 0x0040 +#define APPLESMC_MIN_WAIT 0x0010 #define APPLESMC_MAX_WAIT 0x8000 #define APPLESMC_STATUS_MASK 0x0f -- 1.7.11.1 _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors