Re: [PATCH v2 1/3] dt: bindings: i2c-mux-pca954x: add mux-locked property

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 05/04/2018 03:04 PM, Bastian Stender wrote:
Signed-off-by: Bastian Stender <bst@xxxxxxxxxxxxxx>
---
  .../devicetree/bindings/i2c/i2c-mux-pca954x.txt  | 16 ++++++++++++++++
  1 file changed, 16 insertions(+)

diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt
index 34d91501342e..864ac91f8c1c 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt
@@ -36,6 +36,22 @@ Optional Properties:
      - first cell is the pin number
      - second cell is used to specify flags.
      See also Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
+  - mux-locked: If present, explicitly allow unrelated I2C transactions on the
+    parent I2C adapter at these times:
+    + during setup of the multiplexer
+    + between setup of the multiplexer and the child bus I2C transaction
+    + between the child bus I2C transaction and releasing of the multiplexer
+    + during releasing of the multiplexer
+
+    However, I2C transactions to devices behind all I2C multiplexers connected
+    to the same parent adapter that this multiplexer is connected to are blocked
+    for the full duration of the complete multiplexed I2C transaction (i.e.
+    including the times covered by the above list).
+    If mux-locked is not present, the multiplexer is assumed to be parent-locked.
+    This means that no unrelated I2C transactions are allowed on the parent I2C
+    adapter for the complete multiplexed I2C transaction.
+    The properties of mux-locked and parent-locked multiplexers are discussed
+    in more detail in Documentation/i2c/i2c-topology.

I am not sure about this. I think it will act like the gpmux driver here
so I copied it from
Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt. Is this correct?

Regards,
Bastian

--
Pengutronix e.K.
Industrial Linux Solutions
http://www.pengutronix.de/
Peiner Str. 6-8, 31137 Hildesheim, Germany
Amtsgericht Hildesheim, HRA 2686
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux