Re: [PATCH 4/4] spi: Document option to insert delay between transactions

From: Doug Anderson
Date: Fri Jul 01 2016 - 00:46:07 EST


Hi,

On Thu, Jun 30, 2016 at 12:12 AM, Geert Uytterhoeven
<geert@xxxxxxxxxxxxxx> wrote:
> CC devicetree
>
> On Thu, Jun 30, 2016 at 5:54 AM, <apronin@xxxxxxxxxxxx> wrote:
>> From: Andrey Pronin <apronin@xxxxxxxxxxxx>
>>
>> Some devices may need CS to be deasserted for some time
>> between transactions. Added a new capability to guarantee
>> a delay between SPI transactions for the device.
>>
>> Signed-off-by: Andrey Pronin <apronin@xxxxxxxxxxxx>
>> ---
>> Documentation/devicetree/bindings/spi/spi-bus.txt | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt
>> index 1b7ffd4..87c117a 100644
>> --- a/Documentation/devicetree/bindings/spi/spi-bus.txt
>> +++ b/Documentation/devicetree/bindings/spi/spi-bus.txt
>> @@ -70,6 +70,8 @@ contain the following properties.
>> sleep if there was no SPI activity (msec).
>> - cs-wake-duration - (optional) Time it takes the device to wake up after
>> toggling CS if it went to sleep (msec).
>> +- xfer-delay - (optional) Delay to insert between SPI transactions
>> + to guarantee that CS is deasserted at least for some time.

msec? usec? nsec?

Also, as with the other patch, this should be _before_ the code
change, so this should really be patch 3 not patch 4.