Re: [PATCHv7 1/3] dt-bindings: i2c: document bindings for i2c-slave-mqueue

Wang, Haiyue
2019-06-12T02:46:43Z

在 2019-06-12 07:14, Rob Herring 写道:
> On Wed, Jun 05, 2019 at 09:46:49AM -0700, Eduardo Valentin wrote:
>> Document the i2c-slave-mqueue binding by adding
>> descriptor, required properties, and example.
>>
>> Cc: Rob Herring <robh+dt@kernel.org>
>> Cc: Mark Rutland <mark.rutland@arm.com>
>> Cc: Wolfram Sang <wsa@the-dreams.de>
>> Cc: linux-i2c@vger.kernel.org
>> Cc: devicetree@vger.kernel.org
>> Cc: linux-kernel@vger.kernel.org
>> Signed-off-by: Eduardo Valentin <eduval@amazon.com>
>> ---
>>
>> Changes from V6 to V7:
>> - none
>>
>> .../bindings/i2c/i2c-slave-mqueue.txt | 34 +++++++++++++++++++
>> 1 file changed, 34 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/i2c/i2c-slave-mqueue.txt
>>
>> diff --git a/Documentation/devicetree/bindings/i2c/i2c-slave-mqueue.txt b/Documentation/devicetree/bindings/i2c/i2c-slave-mqueue.txt
>> new file mode 100644
>> index 000000000000..eb1881a4fc0e
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/i2c/i2c-slave-mqueue.txt
>> @@ -0,0 +1,34 @@
>> +===============================================
>> +Device Tree for I2C slave message queue backend
>> +===============================================
>> +
>> +Some protocols over I2C/SMBus are designed for bi-directional transferring
>> +messages by using I2C Master Write protocol. This requires that both sides
>> +of the communication have slave addresses.
> So the address 0x10 in the example below is the address of the I2C
> controller?
>
>> +
>> +This I2C slave mqueue (message queue) is used to receive and queue
Hi Rob, This is mqueue comes from, not from specs directly.
>> +messages from the remote i2c intelligent device; and it will add the target
>> +slave address (with R/W# bit is always 0) into the message at the first byte.
>> +
>> +Links
>> +----
>> +`Intelligent Platform Management Bus
>> +Communications Protocol Specification
>> +<https://www.intel.com/content/dam/www/public/us/en/documents/product-briefs/ipmp-spec-v1.0.pdf>`_
>> +
>> +`Management Component Transport Protocol (MCTP)
>> +SMBus/I2C Transport Binding Specification
>> +<https://www.dmtf.org/sites/default/files/standards/documents/DSP0237_1.1.0.pdf>`_
>> +
>> +Required Properties:
>> +- compatible : should be "i2c-slave-mqueue"
> There is no mention of mqueue (or queue) in these specs. Where does that
> come from? Perhaps something more closely matching the protocol would be
> better name.
>
>> +- reg : slave address
>> +
>> +Example:
>> +
>> +i2c {
> Would there be other slaves?
>
> The common binding states 'multi-master' property should be present.
>
> I need a more complete example.
>
>> + slave_mqueue: i2c-slave-mqueue {
>> + compatible = "i2c-slave-mqueue";
>> + reg = <0x10>;

Hi Eduardo,

Looks like the slave reg missed the key value bit:

https://elinux.org/images/f/f6/ELCE15-WolframSang-ShinyNewI2CSlaveFramework.pdf

Example: reg = <(I2C_OWN_SLAVE_ADDRESS | 0x42)>;

>> + };
>> +};
>> --
>> 2.21.0
>>