From: Jean Delvare Date: Fri, 3 Jul 2015 12:39:05 +0000 (+0200) Subject: hwmon: Document which I2C addresses can be probed X-Git-Tag: v4.2-rc1~20^2~1 X-Git-Url: http://git.cascardo.info/?p=cascardo%2Flinux.git;a=commitdiff_plain;h=97607f9882a0e0d3553382a4c7996d3a37d08268 hwmon: Document which I2C addresses can be probed Add an item to the checklist when submitting a new hwmon driver: only some I2C addresses can be probed, others should not for safety reasons. Signed-off-by: Jean Delvare Reviewed-by: Guenter Roeck --- diff --git a/Documentation/hwmon/submitting-patches b/Documentation/hwmon/submitting-patches index 3d1bac399a22..d201828d202f 100644 --- a/Documentation/hwmon/submitting-patches +++ b/Documentation/hwmon/submitting-patches @@ -81,6 +81,13 @@ increase the chances of your change being accepted. * Provide a detect function if and only if a chip can be detected reliably. +* Only the following I2C addresses shall be probed: 0x18-0x1f, 0x28-0x2f, + 0x48-0x4f, 0x58, 0x5c, 0x73 and 0x77. Probing other addresses is strongly + discouraged as it is known to cause trouble with other (non-hwmon) I2C + chips. If your chip lives at an address which can't be probed then the + device will have to be instantiated explicitly (which is always better + anyway.) + * Avoid writing to chip registers in the detect function. If you have to write, only do it after you have already gathered enough data to be certain that the detection is going to be successful.