[PATCH] hwmon: Add PEC support to the lm90 driver

Add PEC support to the lm90 driver. Only the ADM1032 chip supports it,
and in a rather tricky way, which is why this patch comes with
documentation reinforcements. At least, this demonstrates that the new
PEC support logic in i2c-core can properly deal with chips with partial
PEC support.

As enabling PEC causes a significant performance drop, it can be
disabled through a sysfs file (unsurprisingly named "pec").

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 3 insertions, 0 deletions

diff --git a/Documentation/hwmon/sysfs-interface b/Documentation/hwmon/sysfs-interface
index 346400519d0d..764cdc5480e7 100644
--- a/Documentation/hwmon/sysfs-interface
+++ b/Documentation/hwmon/sysfs-interface
@@ -272,3 +272,6 @@ beep_mask	Bitmask for beep.
 
 eeprom          Raw EEPROM data in binary form.
                 Read only.
+
+pec             Enable or disable PEC (SMBus only)
+                Read/Write