[PATCH] i2c: mux: Add more warnings to i2c-arb-gpio-challenge docs

From: Doug Anderson
Date: Tue Apr 29 2014 - 13:31:26 EST


This adds some more warnings to the i2c-arb-gpio-challenge docs to
help encourage people not to use it in their designs unless they have
no choice.

Signed-off-by: Doug Anderson <dianders@xxxxxxxxxxxx>
---
Documentation/devicetree/bindings/i2c/i2c-arb-gpio-challenge.txt | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/i2c/i2c-arb-gpio-challenge.txt b/Documentation/devicetree/bindings/i2c/i2c-arb-gpio-challenge.txt
index 1ac8ea8..bfeabb8 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-arb-gpio-challenge.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-arb-gpio-challenge.txt
@@ -8,6 +8,12 @@ the standard I2C multi-master rules. Using GPIOs is generally useful in
the case where there is a device on the bus that has errata and/or bugs
that makes standard multimaster mode not feasible.

+Note that this scheme works well enough but has some downsides:
+* It is nonstandard (not using standard I2C multimaster)
+* Having two masters on a bus in general makes it relatively hard to debug
+ problems (hard to tell if i2c issues were caused by one master, another, or
+ some device on the bus).
+

Algorithm:

--
1.9.1.423.g4596e3a

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/